Cold Box Energy Storage:Final Document

Biomedical Engineering 262Design for the Developing World

Instructor:Robert Malkin, PhD

Team Members:Odelia Ghodsizadeh

Scott KasperSean McGuireBrian Robinson

April 21, 2008

I. Abstract

Every year in Africa, millions die from conditions presently treatable with modern medicines. Although theoretically available, these medicines spoil in inadequate refrigeration and are subsequently rendered useless to a large portion of the populace. Local clinics, the most broadly dispersed facility with proper refrigeration, can be more than two days’ travel from areas with little or no reliable electricity of their own. We propose that a novel and cost-effective method of energy collection and storage can provide sufficient and reliable power for dissemination of these drugs to rural communities outside of a hospital’s effective watershed. The energy harvested from the sun, the wind, or mechanical exertion can be used to cool and maintain a 1-2 L box between two and eight degrees Celsius. Specific considerations for selecting the energy collection device include a high energy to physical exertion ratio, maximum power output, average daily output (assuming average conditions for a developing African nation), and device life span. A preliminary search for storage methods candidates resulted in the consideration of capacitor arrays, super capacitors, chemical batteries, ice, and flywheels. These storage devices will be considered based on the ability to meet set power storage limits, average lifespan, and ease of construction. After deducing the optimal system using the criteria of performance, cost, reliability, ease of maintenance, and safety, we hope to overcome this obstacle towards providing a higher standard of living for rural African peoples.

II. Background

Rural regions in third-world countries are currently ill-equipped to store medicines requiring refrigeration. Two major categories of such drugs are antibiotics and oxytocics. The former can be used to treat infections such as acute respiratory infections (ARI), while the latter treat postpartum hemorrhaging (PPH). These conditions are extremely lethal for children and women in Sub-Saharan Africa, with ARI killing 29% of children under the age of 5 and PPH killing 25% of women [1]. An effective, easily-distributed method of storing these types of drugs translates directly to increased life expectancies of a huge percentage of the native population of these countries.

The problem with current refrigeration solutions is they don't meet the cost and energy requirements of rural regions. Conventional refrigerators rely on electricity, which is not always available. Furthermore, solar refrigerators are too large and expensive, with the lifespan of such machines being too short to justify the costs. Though such units are powered in a similar fashion to our proposed design, they are manufactured with storage space as large as 50 liters. Organizations report that space in these refrigerators is only 1/4 occupied on average. These units also cost an average of $3000 [1]. Gas refrigeration units have also been implemented as solutions, but the recurring cost of fuel can be up to $400 per year. Again, price is the issue. Finally, battery-powered units, while being cheap, are unreliable since replacement batteries are not available locally and cannot easily be replaced when the originals run out of power. Because of the constraints of cost and unrealizable power requirements, functional cold boxes in Sub-Saharan African are few and far between, often miles from the site where administration is necessary. Hundreds of thousands of people die every year from the inadequacies of refrigeration.

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An example of an existing cold box is the United Nations Environment Programme's SolarChill unit [2].  This device is similar to our proposed design in that it utilizes solar power to bypass problems with lead batteries and gasoline or other fuel sources.  However, it is large enough to serve as many as 50,000 people and requires 180 watts of solar power to operate.  Solar power costs an estimated $9 per Watt, meaning the solar panels alone would cost $1620.  This unit is a prime example of why smaller, cheaper units would better serve local communities.

Our proposal, then, is the production of a self-sustainable, reliable power source capable of refrigerating a cold box within the desired range of 2-8°C and the desired time span of 24 hours for approximately 1/10th the cost of current available units. We expect to achieve this price drop by sacrificing box storage space. Instead of a 50 liter cavity, our box will have storage for between 1-2 liters, requiring much less power in order to maintain the same degree of cooling. We expect such a box will require approximately 6 Watts of power, which will be provided through a combination of solar paneling and mechanical energy (either a hand crank or a shake-up flux generation system). Such systems are both cheap and capable of being replicated using local materials. We will also implement a system of energy storage (since solar energy is not consistently reliable), a system of translating acquired energy into cooling energy, and a method of delivering the cool air into the insulated cold box. In summary, our goal is to create this safe and user-friendly system using locally-produced materials for under $300.

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III. Specifications

Specification Test Results Status Recommendations

Performance

Fridge chills contents to 2-8°C with appropriate hardware and orientation

Water at 5°C after 5 hrs with fridge in top-loading position and with ducts attached

PASS

20 W minimum power input for chilling cavity to 2-8°C

Peak power 23 W with 28 W solar panel, though not sustained

PASS* Possibly implement higher wattage solar panel; optimization of positioning

After 5 hrs of 20 W input, maintain 1-2 L of water at 2-8°C for 19 hrs without power input

Phase change material maintains temperature within range for 12 hrs

FAIL* Improve refrigerator insulation

Fridge operates at 43°C ambient temperature

13.6°C cavity after 5 hrs with application of hot air to input duct

FAILRerun test; pursue more efficient refrigeration technology; improve airflow

Temperature adjustment mechanism

7.5°C increase with application of detachable seals to exhaust ducts

PASS

Cavity temperature indicator

Dial thermometer through fridge door PENDING

Cost

Maximum $250 $241.80 for prototype; see budget PASS

Reliability

Cooling mechanism failure rate <0.3%

Functional fan in 365/365 trials PASS

Safety

Isolate electrical circuitry and fan from user

Insulated wires, plastic casing, ductwork prevent user from contact with circuitry and fan

PASS

*Subject to additional testing (more below)

*

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Testing 1. Refrigerator power requirements 2. Power generation with solar panel*

3. Temperature maintenance with phase change material* 4. Refrigerator functionality at ambient temperature5. Temperature regulation with duct seals6. Refrigerator cooling system reliability7. Electrical isolation and safety

1. Refrigerator Power Requirements

SpecificationFridge chills contents between 2-8°C with appropriate hardware and orientation

OverviewThe manufacturer rating for the purchased refrigerator is 40 W; however, it is

important to determine whether lower power input can run the refrigeration unit sufficiently to cool the cavity between 2-8°C. The testing will help evaluate the practicality of the refrigeration type (thermoelectric) and the adequacy of the power generating component (solar panel) and other modifications including air ducts and orientation changes.

ProcedureA power supply was obtained and set to an output of

19.55 W and connected to the intact refrigerator (Figure 1). An aquarium thermometer (Figure 2) was placed inside the refrigerator so that temperature could be read while the refrigerator remained closed. Temperature measurements were then taken over time as the refrigerator cooled. The test was repeated with ductwork attached to simulate the increased airflow resistance the system will experience when inside the insulating box (Figure 3).

At a successive stage, the temperature of 1.35 L of water was monitored with the ducts attached and with the fridge in a top-loading position (Figure 4). Power inputs of 16 W and 23 W were supplied in separate trials.

ResultsThe original

refrigerator was able to cool down to an appropriate temperature with a power input less than 40 W. In

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Figure 2: Digital thermometer

Figure 1: Fridge and supplied power

Figure 3: Refrigerator with air ductsFigure 4: Refrigerator with air ducts in the top-loading position. Water is used to simulate medicine

this test, it took the refrigerator 50 minutes to cool down to 2°C from room temperature (Figure 5). The refrigerator was able to cool down as efficiently as before with the air ducts attached. It took 52 minutes to cool down to 2°C from room temperature compared to 50 minutes without the air ducts (Figure 6).

The results of cooling water with the fridge in the top-loading position can be seen below (Figure 7). The contents appear to have reached a minimum of 11.5˚C after five hours at 16 W. After 5 more hours, the temperature reached 8˚C. A power input of 23 W realized a temperature of 5˚C after 5 hours.

Testing Refrigerator's Ability to Maintain Temperature of 1.35 L of Water

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2. Power Generation With Solar Panel

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Figure 5: Original refrigerator cooling profile Figure 6: Refrigerator with ductwork cooling profile

Figure 7: Cooling profile of water in refrigerator with ductwork and in a top-loading position for different power inputs

Specification20 W minimum power input (for chilling refrigerator cavity between 2-8°C)

OverviewThe objective of this test was to determine the actual power output of the

purchased solar panel, rated 28 W, over time. In order to power the refrigerator, the solar panel will be at a fixed position during the course of the day. Because the angle of incidence of the sun’s rays will change over the course of the day, it is important to know how the power output of the solar panel will change. It is also important to know what the actual maximum output power of the solar panel is and whether it meets the 20 W requirement determined previously.

ProcedureA 28-watt solar panel (Figure 8) was connected to a test load of 4Ω (two 2Ω 25W

resistors connected in series). A multimeter was then attached to record the voltage (Figure 9). Power was then calculated by the relationship P=V^2/R. On a sunny day, the solar panel was angled towards the sun for the maximum power output.

Expected Outcome:Based on previous experiments which yielded 77% efficiency for solar panels, the

28 W panel was expected to provide up to 22 W.

ResultsMeasurements were taken for a period of 2.5 hours. The initial power output of

the solar panel was 18.5 W, which then increased to a maximum of 19.36 W. As time increased further, the power steadily decreased (Figure 10).

When this same testing was done on a hotter day when the sun was brighter, a maximum power of 23 W was attained. However, during this test clouds would repeatedly cover the sun and the power output would drop as low as 1 W.

The overall goal of the solar panel was to act as a power generating device that would provide 20 watts of power to the refrigerator. On a very sunny day, the solar panel was able to achieve a power output of 23 watts, so in this regards the solar panel was successful. However, the solar panel was not able to sustain this power output. If clouds cover the sun, the power output decreases dramatically. In addition, the changing position of the sun relative to the solar panel causes the power output to drop off over time.

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Figure 8: 28 W Solar panelFigure 9: Resistors and multimeter for solar panel testing

It was shown that on days when the sun is brighter, there will be a larger power output. In some developing world countries that have brighter sunshine the power output will be greater; it is estimated that the targeted areas for distribution of the cold box have 5 hours of sunlight, which is reflected in other specifications and tests [1]. Regarding the panel orientation, it is possible that the positioning of the solar panel could be further optimized to maximize the total amount of power outputted over the course of a day.

Further testingThe capability of the solar panel will be tested directly by connected it to the

refrigerator on a sunny day. Power output of the solar panel will be monitored concurrently with refrigerator temperature over time. It is expected that the solar panel will be able to power the refrigerator for fivehours on a clear day, but not continuously, and that the refrigerator cavity will reach 2-8°C.

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Figure 10: Solar panel output on a sunny day (initial data set)

3. Temperature maintenance with phase change material (PCM)

SpecificationMaintain 1-2 L of water at 2-8°C for 19 hours without power input after 5 hours

of 20 W input

OverviewBecause of the decision to utilize solar power, energy can only be collected for an

estimated 5 hours per day. For the remainder of the day, the refrigerator will not be powered and therefore unable to actively cool the system. The PCM, which has a melting point between 2-8°C, is chilled while the fridge runs, and serves as a ‘thermal hurdle’ when power becomes unavailable, absorbing the heat from the surrounding area and keeping the contents of the fridge cool. It is necessary to evaluate whether after five hours of cooling the PCM can actually keep the fridge cavity within the desired temperature range for the duration without power, 19 hours.

ProcedureThe refrigeration unit was complete with ductwork and set on its back. 23W, the

peak power output of the solar panel, was applied to the unit. The ambient temperature was 21˚C. The unit was closed and remained closed for five hours. At that time, the unit was opened and the state of PCM material (frozen or unfrozen) was visually evaluated.

Expected OutcomeDue to the amount of heat the PCM panel could absorb (85-95 kJ/panel), it was

initially believed that the box could indeed maintain this temperature range.

ResultsThe cavity remained within the temperature range for twelve hours. Notably, this

test was done without the ultimate level of insulation expected. At the time of this writing, the insulating box was not available for combined testing.

Further testingResistance to heat transfer and warming will be evaluated again, with the basic

procedure repeated, but with the extra insulating box around the refrigerator. It is expected that the combination of insulation and phase change material will keep the fridge contents between 2-8°C for the 19 hours required when the ambient temperature around 21°C. This testing will extend further to encompass the complete cold box unit (solar panel, fridge, PCM, insulating box) for the 24 hour cycle.

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4. Refrigerator functionality at ambient temperature

SpecificationFridge operates at ambient temperature of 43°C

OverviewThough the cold box reaches the acceptable range of 2-8°C in ambient conditions

in the lab, this is not necessarily indicative of ambient conditions in sub-Saharan Africa, where the device will primarily be used. Increasing the intake air temperature can simulate actual conditions and help determine whether performance will be adequate.

ProcedureTo simulate hot weather, a hair drier was used to blow warm air (44°C) into the

input duct of the refrigerator (Figure 11). All other conditions were the same (1.35 L of water in the cavity, measurements acquired in ambient weather). Temperature was measured as a function of time over a 5-hour period. The box was powered via 12-volt electrical outlet.

Expected OutcomeWe expected the cavity temperature to increase with the hot air, especially given

the limitations of thermoelectric cooling.

ResultsThe temperature did not equilibrate within the acceptable range (Figure 12).

However, due to hot air being blown directly into the duct, this test was not necessarily realistic. It is likely that ambient conditions would not be as harsh, and thus the cavity temperature would be expected to be lower than the 13.6°C reached in this test. The test may need to be rerun as 1) the fridge cavity was not at 43°C at the time of cooling, 2) the refrigerator received full power rather than the restricted 20 W, and 3) hot air was blown directly into the duct rather than heating the surrounding air. These factors likely influenced the performance of the refrigerator such that ambient conditions were not

Figure 11: Hairdryer for heating air of intake duct

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properly simulated. The predictions remain pessimistic, however, by virtue of the thermoelectric cooling system.

Effect of Increased Ambient Temp.

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Figure 12: Refrigerator cavity cooling 44°C ambient temperature

5. Temperature regulation with duct seals

SpecificationTemperature adjustment mechanism

OverviewIt is possible that the cavity temperature of our cold box could fall below the floor

temperature of 2°C. This would happen if ambient temperature were particularly low. The thermoelectric cooling system in the box works by creating a temperature differential, so if the weather were relatively cold (16°C or lower), the cavity temperature would drop lower than expected. The user of our device should have a simple way to raise the cavity temperature in the event of a cold day.

ProcedureThe cold box, with ventilation ducts

attached, was placed outside and powered on a cold day (13°C) with 1.35 L of water inside. After allowing the cavity temperature to equilibrate, it was found that the temperature did indeed drop below the floor temperature of 2°C. Detachable duct seals were then fixed onto the ends of the heat exhaust ducts, and temperature was measured as a function of time until again equilibrating several hours later (Figure 13).

Expected OutcomeBy sealing off the heat exhaust ducts,

we expected the heat to remain in the cavity instead of being pumped out. This would be accompanied by a rise in cavity temperature until it equilibrated several degrees higher.

ResultAfter approximately 2 hours, the cavity temperature rose 7.5°C (Figure 14). Our

results were consistent with our expectations, and this test was a success. The ducting system allows for basic and effective user control by providing a means to raise cavity temperature by a maximum of approximately 7.5°C.

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Figure 13: Detachable duct seals on exhaust ducts for temperature regulation

Effect of Sealing Heat Exhaust Ducts

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Figure 14: Refrigerator cavity temperature with sealed exhaust ducts

6. Refrigerator cooling system reliability

SpecificationCooling mechanism failure rate <0.3%

OverviewThe cold box is expected to function for at least one year. The fan operation and

cooling system were judged as most likely to malfunction after repeated use and subsequently tested for reliability.

ProcedureThe refrigerator, with ducts attached and in the top-loading position, was

connected to a 20 W commercial power supply and switched on and off 365 times to simulate daily powering of the refrigeration unit. The fridge was considered “on” after the fan rotated and full velocity and current delivery through the device was observed via ammeter to be sustained.

Expected OutcomeIt was expected that the refrigerator would function properly for all trials.

ResultsThe refrigerator cooling system switched on and off without issue for all 365

trials.

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7. Electrical isolation and safety

SpecificationIsolate electrical circuitry and

fan from user

OverviewTo prevent unintentional shock,

the electrical compartments of the system are unable to be reached during normal operation (Figure 15). Because of the design of the system, isolation of the electronics coincides with isolation of the fan and heat sink, two elements which present their own risks.

ProcedureWith the refrigeration system in a mock real-life situation, wherein bottles of

water represented medicine, three persons, simulating untrained workers, unassociated with the project were asked to deposit and retrieve the bottles. These individuals were not informed of the purpose of the experiment. Figure 15 shows tester instructions.

Expected OutcomeDue to the construction of the system, it seemed unlikely that a user would

accidentally come into contact with these elements. With the plastic housing in place as well as lengths of ductwork present over each vent, one would actively have to reach these components to incur any injury. Safety will further be increased once the refrigerator is placed within the insulating box; this box will add another degree of separation from operator and dangerous units. Furthermore, only two wires are exposed and both are insulated.

ResultNone of the persons asked to perform these tasks were even approaching danger. The

refrigeration unit itself provides a plastic encasement for these parts. Originally, the manufacturer placed plastic grating over the vents to prevent accidental injury. While these grates were removed, 12 inches of ductwork was placed over these vents. Furthermore, the unit will ultimately be enclosed in an insulating box, further reducing the likelihood of incidental contact.

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Figure 15: The electronics, heat sink, and fan are normally protected within plastic housing. Housing was removed to show their location.

IV. Completed Work

This portion of the cold box projects consists of three main components: the cooling system, the power generation component, and the energy storage component. Additionally, a temperature adjustment mechanism has been included. The overall design is shown in Figures 16 and 17. The solar panel, placed outside, collects energy for an estimated 5 hours. During this period, the refrigeration unit powers on and cools the cavity which contains 1-2 L of medicine (simulated by water) and one panel of phase change material. Across durations with insufficient sunlight to power the fridge, the PCM keeps the cavity and contents within the desired temperature range of 2-8°C. Cavity temperature is non-regulated, but temperature may be increased with application of duct covers. The complete cold box will have additional insulation, but this aspect is beyond the scope of this paper.

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Figure 16: Schematic of cold box. The red box is the top-loading refrigerator with sealable exhaust ducts on either side and an air intake duct at the bottom. The DC adapter of the fridge connects into the control panel and is connected to the positive and negative wiring of the solar panel. The outline of a larger box represents the insulating container in which the refrigerator will be placed. Dial thermometer and adapter casing (for isolating) not pictured. Figure not to scale.

Cooling system

Cooling was accomplished with a 4L thermoelectric refrigerator (Figure 18). Thermoelectric cooling, which involves the generation of a heat pump via the Peltier effect, was selected because it is cheaper than compression refrigeration and more practical and sustainable in this application than a non-cyclic system (such as ice). The unit (25”x 20”x 25”) used in this design included a thermoelectric device, aluminum heat sink, fan, and cavity. The 4L cavity provides enough room for the specified 1-2 L of medicine as well as several panels of PCM which store energy. The device runs

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Figure 17: Close up of the refrigeration unit and cutaway view. The DC adapter connects to the inlet at the control panel, where the switch and “on” light are also located. The panel is wired (not shown) to the thermoelectric unit, heat sink, and fan. The phase change material is placed inside the box alongside the medicine (not pictured). Figure not to scale.

optimally at 40 W with a 3 A current, but can function on as little as 20 W. It is also insulated, but given the co-production of a large insulating box, this aspect is not critical. Three 4”x1” vents located next to the fan, as well as a 3” vent located over the fan, are

necessary for heat conduction. While initially grated, these were removed to reduce airflow resistance. In order to vent air once the refrigerator is inside the larger insulating box, aluminum ducting was attached to the side exhaust vents and the back intake vent. The top exhaust vent, which was found to expel relatively little air, was covered. The refrigerator is able to cool its contents with 20 W in a top-loading position and with the ducts attached.

The refrigerator includes a DC car adapter which can connect the power source to the unit.

Power generation

This component must produce enough energy to run the refrigerator such that the contents are preserved within the desired temperature range. It must also be compatible with the other components and fit into the overall budget. Solar power has the advantage over other power generation systems that the only input necessary is the exposure to sunlight. There are no necessary consumed materials and there is minimal human interaction for proper operation. Because solar energy is not always available, the panel must be efficient enough to provide sufficient energy to be stored and utilized during these periods.

Solar panels are generally expensive, and thus the panel choice was limited to the 30 W and below range. This design used a 28 W solar panel from Sun Electronics, selected for its power rating and reasonable cost (Figure 19). Because total sun exposure cannot be predicted, it was deemed necessary to attempt to collect as much power in as little time as possible. The panel is capable of generating 23 W of power on a sunny day.

Energy storage

The temperature within the refrigerator must be preserved within the desired range even when the refrigeration unit is not supplied with enough power to run. Additional insulation will be provided through a separate project, but a mechanism of energy storage is useful in maintaining the temperature. A substance placed inside the

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Figure 18: 4L thermoelectric fridge

Figure 19: 28 W Solar panel

box and chilled with its contents will absorb thermal energy from the cavity and resist increases in temperature. It is optimal to use a substance with a melting point within the 2-8°C range to keep the cavity at the required temperature.

The phase change material incorporated in the design was donated from TCP Reliable, Inc. (Figure 20) The material is encased in 6”x 6”x 1” rigid plastic panels. The material has a melting temperature of 5°C, and each panel requires 85-95 kJ of heat to melt; conversely, this amount of heat must be removed from the system to freeze the material. Up to two panels can be placed inside the refrigerator’s cavity, but space is then limited for medicine.

Temperature adjustment

In the event that ambient temperature drops to around 20°C or below, it is possible that the fridge can become colder than the desired range. Implementing a temperature adjustment mechanism can prevent this occurrence. Currently, a digital thermometer is used to monitor temperature, but a dial thermometer, which does not require consumable parts, has been factored into the final design. Removable plastic draft seals applied to the ends of the exhaust ducts can restrict airflow and increase temperature up to 7.5°C (Figure 21).

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Figure 20: Phase-change material. Note: the PCM tested was a clear liquid

Figure 21: Draft seal/vent blocker

Construction and Usage

Summary: This manual details the production, testing, and usage of a solar-powered

refrigeration system that operates at a temperature range of 2-8°C. Its purpose is to store temperature-sensitive medicines in areas with high temperatures but no electrical grid. The device operates by collecting solar energy with a 28 W solar panel and using this input to power a thermoelectric device, heat sink, and fan. Phase change materials (PCM) were incorporated to increase the thermal inertia of the refrigerator’s cavity within the target range. In addition to housing the PCM panel (dimensions 6”x 6”x 1”), the cavity allows for the storage of 1 L of medicine vials. An independently designed insulating box was developed to improve the system’s ability to remain sufficiently cold in high ambient temperatures.

PARTS LIST

Parts (see above for descriptions)4 L Thermoelectric refrigerator28 W Solar panel1 Phase change material panel (up to 1 L)4’ Aluminum ducting2 Draft seals of duct diameterThermometerDuct tape2 Insulated wires, 3’-10’ 10” twine

Construction:

Step 1: Placement of the Solar Panel1. Locate an area with few overhead obstructions and an obstructed line of sight

from the sun for as long as possible, but definitely included the hours of 10 AM to 3 PM.

2. Position the solar panel facing towards the equator (South if in the Northern hemisphere, North if in the Southern Hemisphere) for maximum exposure. Restrain the device to prevent tipping and breaking.

3. Connect two wires to the panel’s outputs, one each to the positive and negative terminals (Figure 22).

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Figure 22: Wires connected to positive (red) and negative (black) terminals on the back of the solar panel

Step 2: Preparing the refrigerator1. Remove grilling from vents. 2. Place the one phase change material panel and thermometer into the cavity

and close the cavity. 3. Connect the positive wire from the solar panel to the male end of the adaptor.

Connect the negative wire to either side-flange (Figure 23). 4. Connect the power adaptor to the refrigerator. 5. Set the power switch to the ‘on’ position permanently.

Step 3: Prepare for integration into insulating box1. Attach 1’ of ducting to each side vent using duct tape (or some acceptable

alternative). Ensure sufficient space for ventilation available around insulating box.

2. On the end of each duct originating from a rectangular vent, attach the housing for the draft seal.

3. Attach the seal to the housing with twine (Figure 24).4. For placement within the box, refer to the instructions provided by the

designers of that project.5. Cut ducting to length.

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Figure 23: Wires connected to positive lead (red) connected to male end of adapter, negative lead (black) connected to side-flange

Figure 24: Draft seal housing attached to duct with seal connected with twine

Visual User Instructions

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Figure 25: Completely constructed refrigeration unit

Figure 26: Pictorial instruction indicates correct temperature range and incorrect solar panel placement

Limitations:

The primary limitation of this device is its dependence on received solar power. While the use of PCM increases the refrigerator’s ability to maintain the target temperature, the device can only operate properly for two days without any energy input. Due to the size of the cavity, only one PCM panel can be inserted while still leaving sufficient room for medicine storage. Furthermore, depending on the ambient temperature, the thermoelectric device may be unable to reach the target temperature range.

Directions for Use

Each night, insert the duct plug into its housing so as to halt the flow of (hot) air into the unit. Upon initial installation, allow the box at least two sunny days to reach the target temperature range. At this point, check the thermometer to ensure that the temperature has, in fact, reached an acceptable level. If so, place medicines into the cavity alongside the PCM material already present. If not, allow the unit one more day of sun. If temperature is below the desired range, duct covers may be applied to increase the temperature. Upon achieving working condition, the unit should be self-sustaining; simply deposit or withdraw medicines as necessary.

V. Schedule

Figure 27: Schedule for Feb 6 - 23

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Figure 28: Schedule for Feb 24-March 14

Figure 29: Schedule for Mar 14-Apr 2

Figure 30: Schedule for Apr 1-25

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VI. Budget

The development is detailed in Table 1, below, and the cost for the prototype is itemized in Table 2.

Table 1: Development budgetItem Vendor Price ($)4-L Thermoelectric Refrigerator Target 42.692 Draft Seals Home Depot 10.58Aquarium Thermometer PetSmart 9.60Thermometer Target 8.53Thermoelectric Power Generation Module www.tellurex.com 28.9528-Watt Solar Panel www.sunelec.com 150.00Aluminum Duct Tubing Home Depot 16.00

Total 266.35

Table 2: Prototype budget (one unit)Item Est. Cost ($)4-L Thermoelectric Refrigerator 42.692 Draft Seals 10.58Thermometer 8.5328-Watt Solar Panel 150.00Aluminum Duct Tubing 16.00Phase Change Material * 6.00Wiring <3.00Epoxy, twine <5.00

Total 241.80

*The phase change material was free for our development budget because it was donated (from TCP Reliable, Inc).

VII. Facilities and Personnel

To develop our project, we utilized the BME 262 Lab and the equipment therein, including power supplies, measurement tools such as ammeters and voltmeters, resistors, and software for data recording and analysis.

The design team consists of four undergraduates pursuing biomedical engineering degrees: Odelia Ghodsizadeh, Scott Kasper, Sean McGuire, and Brian Robinson. Beyond the core team, the vital personnel include Dr. Robert Malkin and Renuka Nayani. These individuals possess important information concerning the resources of the targeted region, engineering experience, and a refined understanding of the problem at hand.

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ODELIA GHODSIZADEHOdelia.ghodsizadeh@duke.edu

Duke University, Box 94249, Durham, NC 27708 (614/562-6702)760 Waterton Dr., Westerville, OH 43081

EDUCATIONDuke University, Pratt School of Engineering, Durham, NC; expected graduation: May 2008B.S.E., Biomedical Engineering; Neuroscience certificate. Cumulative GPA: 3.11/4.0. GRE: 780 Quantitative/ 720 Verbal

Coursework: Modeling Cellular and Molecular Systems, Biomaterials, Biomechanics, Chemistry, Electrobiology, Biomedical Electronic Measurement, Computer Methods in Engineering, Signals and Systems, Transport Phenomena, Business in Technology Based Companies, Statistics

Honors: National Merit Finalist, Robert Byrd Scholarship

EXPERIENCENorthwestern UniversityResearch fellow, Summer Internship in Neural Engineering, Summer 2007 (40 hrs/week)

Performed and analyzed locomotor experiments with neonatal mice, including laminectomy and electrophysiological recordings

Presented study in poster session and research paper

Duke UniversityResearch assistant, Biomedical Engineering department, Fall 2006-Spring 2007 (8 hrs/week)

Aided in experiments utilizing elastin-like polymer as a drug carrier; laboratory methods include protein purification, gel electrophoresis, BCA and cell viability assays, turbidity and glutamate readings

Coauthor of abstract accepted by Canadian Society for Clinical Investigation

Ohio State UniversityResearch assistant, Chemical and Biomolecular Engineering department, Summer 2006 (25 hrs/week)

Involved in development of PLGA scaffolds for tissue engineering experiments Cultured and seeded cells, monitored effects of scaffold porosity and alignment on growth

Nestlé Research and DevelopmentEngineering aide, Marysville, OH, Summer 2004 and 2005 (40 hrs/week)

Conducted investigation of blend and roast effect on foam quality Operated equipment for near-infrared and gas chromatography testing Performed and documented trials for freeze-drying, air injection, and sintering projects

SKILLS Knowledge of research design and data analysis; laboratory experience Exceptional organization, recordkeeping, and written communication skills MS Office, MATLAB, LabVIEW

ACTIVITIESDuke University Start-Up Challenge, 2007-2008JUPITER undergraduate electronic journal, editor, 2007-2008PRISM multicultural selective house, treasurer, 2006-2007Project Child tutoring program, volunteer, 2004Devised and implemented activities to improve elementary students’ proficiency in math and reading

SCOTT J. KASPER

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sjk12@duke.edu(630) 310-0355

Current Address: Duke University Box 99422, Durham, NC 27708Permanent Address: 709 Oakwood Dr., Westmont, IL 60559

EducationDuke University, Durham, North Carolina

Expected Spring 2008 Biomedical Engineering major, cumulative GPA 3.141/4.0 Relevant Coursework: Multidimensional Calculus, Linear Algebra, Physics (mechanics,

electricity, magnetism, optics), Cellular Systems, Biomaterials, Bioelectricity, Signals and Systems, Statistics, Biology, Circuits, Engineering with MATLAB

United States Military Academy, West Point, New York Spring 2005

Cumulative GPA (Fall 2004-Spring 2005): 3.81/4.0 Relevant coursework: Chemistry, Information Technology, Military Leadership Distinguished Dean’s List 2004 and 2005

Benet Academy, Lisle, Illinois Spring 2004 Cumulative GPA: 4.0/4.0; SAT: 1570 National Merit Scholarship Finalist, Graduated with First Honors, National Honor

Society, Spanish National Honor Society, Scholar-Athlete Award for Track & FieldWork Experience

Westmont Park District (May 2006-August 2006): Worked as a member of Westmont Park Patrol; responsible for security of several Westmont public parks. Assisted in large public gatherings and sponsored functions. Underwent training in public relations, CPR, first aid, and surveillance reports.Vector Marketing (May 2005-August 2005): Commission-based sales rep trained to sell Cutco cutlery products. Underwent training in sales and public relations.United States Army (June 2004-May 2005): Experienced basic training to learn survival and basic military skills. Developed as a cadet and student according to a four-tier system: physical, intellectual, military, and moral-ethical. Trained in platoon leadership, team dynamics, team building, and job designation to accomplish critical tasks. Participated in rigorous intramural and physical education programs.Hinsdale Hospital (June 2001-August 2003): Volunteered at Hinsdale Hospital. Underwent training in public relations accessing hospital information databases.

Leadership and ActivitiesWayne Manor: Selective living community. Tutor children at the nearby Hillandale Elementary School. Participate in campus/community service. Organize campus social events. Awarded 2006 Key Volunteer of the Year Award by Volunteer Center of Durham.Transfer Advisory Counselor (TAC): Counsel and mentor Duke transfer students. Undergo training in counseling and event-planning.DukEngineer: Interview and report on high-profile engineering entrepreneurs for campus engineering periodical.Engineers Without Borders: Plan and raise funding for humanitarian project in Uganda. Assist in planning and construction of local playground for handicapped children in Durham, NC.

Skills and InterestsTechnical Skills: proficient in all Microsoft Office programs, MATLAB, use of oscilloscopes and circuit construction; familiar with XML and XHTMLInterests: running, weightlifting, racquetball, philosophy, literature, music, government

Sean T. McGuirestm21@duke.edu

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Duke University, Box 95345, Durham, NC 27708 (724-713-7298)222 Pintail Road, Gibsonia, PA 15044 (724-443-0062)

EDUCATIONDUKE UNIVERSITY: Durham, North Carolina. Major: Biomedical Engineering Graduation: May 2008 GPA: 3.77/4.00 Dean’s List Fall 2004, 2005, 2006, 2007 & Spring 2006, 2007 Relevant Coursework: Organic Chemistry, Biochemistry, Cellular Biology

EXPERIENCEPratt Fellows Research Intern Spring 2007 – Spring 2008 Developed analytical methods to predict, detect, and monitor respiratory depression due to

opioids during post-operation recovery. Patient data was gathered at the University of South Carolina medical school and processed using numerical methods.

Pittsburgh Tissue Engineering Initiative (PTEI) Intern Summer 2006 Researched and aided in the development of a tissue-engineered urethral wrap derived

from bone marrow progenitor cells to prevent stress-urinary incontinence. Teaching Assistant Fall 2006 Provided review sessions, group tutoring, and private assistance to students requesting help in a

sophomore engineering class.

LEADERSHIP/ACTIVITESDelta Smart House Principal Engineer Fall 2004-Spring 2005 and Spring 2006 Proposed and researched potential HVAC designs to fulfill demands of researchers and

residents of the Smart House. Design additional amenities for house residents. College Republicans Treasurer Fall 2005- Spring 2006 Budgeted and recorded monies for the 2005 academic year. Included collecting dues, attending

North Carolina’s College Republican Conference, and coordinating multi-group efforts to fund distinguished speakers

Delta Kappa Epsilon Social Chair, Intramural Sports Captain Fall 2005-Spring 2006 Manage fraternity’s social calendar of inter-fraternity events, events with sororities, mixers,

sport outings and fall recruitment events.

HONORS AND AWARDS Eagle Scout Organized and directed 40+ hour project to rejuvenate the Depreciation Lands

Museum in Allison Park, PA. Order of the Arrow Boy Scout Leadership Brotherhood. Selected by peers for outstanding

leadership and exemplifying scouting principles.

OTHER Ten years of classical piano training culminating in one year of competition.

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Brian S. Robinsonbsr2@duke.edu 18 Hickory Knoll Court, Lutherville, MD 21093 443.850.4816

EDUCATIONPratt School of Engineering, Duke University, Durham, NC

Candidate for Bachelor of Science in Biomedical Engineering Expected May 2008

Courses Include: Computational Neuroengineering, Models of Cells and Molecular Systems, Biomedical Electronic Measurement, Electrobiology, Theoretical Electrocardiology, Signals and Systems, Independent Study in Fractionation during Atrial Fibrillation

Cumulative GPA: 3.71

University of Cape Town, Cape Town, South Africa Fall 2006 Study Abroad experience

Dulaney High School, Cockeysville, MD Fall 2000 – Spring 2004 Cumulative GPA: 4.0 SAT 1520 (800 Math / 720 Verbal) National Merit Scholarship Finalist

WORK EXPERIENCEAllied Orthopedics, Summer Intern, Brooklyn, NY Summer 2007

Trained with Certified Orthotist Prosthetists to assist in designing prosthetic and orthotic devices Created devices from components and raw materials Surveyed patient needs based on device specifications to make device modifications

RNS Scanning Solutions, Founder and Manager, Baltimore, MD 2002- Present Created a business that converted written medical documents into electronic records Devised and implemented a method for indexing and organizing over 20,000 medical charts Hired, trained, and supervised 8 employees

Camp Airy, Camp Counselor, Thurmont, MD Summers 2004 - 2006 Supervised campers 24 hours per day and fostered community building Instructed athletic activities to 7-16 year old campers

VARSITY ATHLETICSVarsity Duke Fencing Team 2004-Present

Member of the Division 1 Duke Varsity Men’s Fencing Team Participated in practice, training, and lesson regimen 10+ hours per week

ACTIVITIESSHAWCO, Cape Town, South Africa Fall 2006

Taught English and Biology to students in the underprivileged Khayelitsha township of Cape Town

Part of the Students’ Health and Welfare Centres Organization Club Volleyball Team, University of Cape Town Fall 2006

Trained and practiced during the week Participated in several matches representing University of Cape Town

Club Fencing Team, University of Cape Town Fall 2006 Attended fencing practices and competed in intercollegiate meets

SKILLS/ INTERESTS Computer Skills: Matlab, LabView, basic Java and C++ Interests: Worldwide travel, Hiking and the outdoors, Fencing, Volleyball

Renuka Nayani5507 Butterfly Lane, Apt. 202 Durham, NC 27707

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949.412.1539 renuka.nayani@fuqua.duke.edu

EDUCATIONDUKE UNIVERSITY, The Fuqua School of Business, Durham, NCMaster of Business Administration, May 2008. GMAT: 710. Organized Duke’s Social Impact conference, attended by 300+ students and practitioners. Acted as board member of local non-profit Durham Companions. Elected as Events Coordinator of Social Impact Club, responsible for managing 3 1st year students. In charge of corporate relations for Association of Women in Business. Member of Finance Club.

UNIVERSITY OF CALIFORNIA AT IRVINE, Irvine, CABachelor of Science, Computer and Electrical Engineering, June 2001. GPA: 3.6. GRE( Math ):800. Member of Tau Beta Pi Engineering Honor Society. Member of Campus-wide Honors Program (selected among top 15% of all admitted students).

EXPERIENCESummer 2007 Morgan Stanley, New York City, NY Summer Associate - Investment Banking

Performed LBO analysis of technology and retail companies to determine feasibility of takeover

Prepared pitch materials for potential buyers of a technology company valued at $23Bn

Developed sell-side materials for consumer products company divesting $1Bn asset

Prepared an analysis of the Food and Beverage sector to determine strategic M&A options for diversified food company

Prepared case study on cross-border mergers and acquisitions which encountered regulatory delays, studying the impact on acquirer share price and probability of deal completion

2002 – 2006 Accenture LLC, El Segundo, CAExperienced Consultant, 2005 - 2006

Managed a team of seven analysts to develop module for Insurance underwriting

application which enabled the client to process higher customer volumes; delivered module ahead of schedule and under budget by 50%.

Developed project management methodology for non-profit agency which resulted in smaller schedule variances across projects and more accurate earned value metrics.

Ranked in the top 10% of all consultants in the Global Architecture Group at the firm

Consultant, 2004 - 2005 Selected by senior management from among 10 other consultants to coordinate

product testing effort; received award from client for on time completion of testing despite aggressive deadlines.

Managed the transition between on-shore and off-shore application teams in India to achieve faster turnover of production defects.

Developed strategy with management to improve the firm’s bargaining position in global software contract bids which resulted in more competitive pricing for software proposals

Analyst, 2002 - 2004 Replaced client’s existing online framework to enable the consolidation of existing

sales channels and to improve online request processing time by 30%.

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Led cross functional team of 10 developers to increase scale of client product offerings online, increasing the client’s forecasted revenue by 80%.

Developed online welfare application for state of California which resulted in significant savings for the state by reducing welfare fraud.

ADDITIONAL INFORMATIONPerformed Indian Classical Dancing for 12 years in venues across California. Volunteered extensively for battered women shelter, mentoring and counseling children. Consulted for Nicaraguan social venture fund, Agora Partnerships. Enjoy traveling and cooking.

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Robert Allen Malkin, PhD, PEProfessor of the Practice of Biomedical Engineering Department

Duke Universityrobert.malkin@duke.edu

EDUCATION Ph.D., Electrical Engineering, May 1993DUKE UNIVERSITY, Durham NC Title: Estimating Defibrillation Efficacy Using Upper

Limit of Vulnerability Testing Advisor: Dr. Theo Pilkington M.S., Electrical Engineering, December, 1990DUKE UNIVERSITY, Durham NC Title: Optimal Bayesian Sequential Estimation of

Defibrillation Parameters Advisor: Dr. Theo PilkingtonB.S., Electrical Engineering / B.S., Computer Engineering, May, 1984 THE UNIVERSITY OF MICHIGAN, Ann Arbor, MI Magna Cum Laude Senior Research Project: Extracting the Fetal ECG

from the Maternal ECG Senior Research Advisor: Dr. Janice Jenkins

PROFESSIONAL ENGINEERING LICENSE (PE in TN-#106969): 2001-

ACADEMIC EXPERIENCE2004-present DUKE UNIVERSITY, Durham, NC

Professor of the Practice of Biomedical Engineering2004-present DUKE UNIVERSITY - ENGINEERING WORLD HEALTH

Director2001-present ENGINEERING WORLD HEALTH Corporation, Memphis, TN

Chair, Board of Directors2003-2004 THE UNIVERSITY OF MEMPHIS, Memphis, TNProfessor of Biomedical Engineering2000-2003 THE UNIVERSITY OF MEMPHIS, Memphis, TN

Herbert Herff Associate Professor of Biomedical Engineering1999 - 2003 THE UNIVERSITY OF MEMPHIS, Memphis, TNAssociate Professor of Biomedical Engineering2000-2004 UNIVERSITY OF TENNESSEE, Memphis, TN

Adjunct Associate Professor of Biomedical Engineering

1995 - 1999 THE UNIVERSITY OF MEMPHIS, Memphis, TNAssistant Professor of Biomedical Engineering1995 - 2000 COLUMBIA UNIVERSITY, New York, NY

Adjunct Associate Research Scientist1995- 2000 UNIVERSITY OF TENNESSEE, Memphis, TN

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Adjunct Assistant Professor of Biomedical Engineering

1993 - 1995 THE CITY COLLEGE OF NEW YORK, New York, NYAssistant Professor of Electrical Engineering

1993 DUKE UNIVERSITY, Durham, NCPostdoctoral Fellow, Directed by Dr. Raymond Ideker,

INDUSTRIAL EXPERIENCE1987 - 1989 EM MICROELECTRONICS, Marin, Switzerland

IC Design Engineer and Project Engineer1984 - 1987 CORDIS CORP., Miami, Florida

IC Design Engineer and Project Coordinator1983 - 1984 SARNS-3M, INC., Ann Arbor, MI

Programming Consultant

HONORS AND AWARDS

Cleveland Heights High School Hall of Fame, 2006 Selected as a Instructional Technology Fellow, Duke

University 2005-2006 Selected as Memphis “Stand-Out” by Memphis Daily

News, May 2004 Jefferson Award Winner, for public service, 2004 Memphis Engineering Council featured engineer of the

year (UofM), 2004 Recognition of Service Excellence from The Ministry of

Health of the Republic of Nicaragua, 2002 Received Herff Outstanding Faculty Research Award,

2001 Named to Herbert Herff Endowed Chair, 2000 Outstanding Service Award, IEEE-Memphis Section,

1998 Senior Member Grade Award, IEEE, 1998 Established Investigator Award, American Heart

Association, 1997 Innovation and Excellence in Undergraduate Education

Award, CCNY President, 1995

PEER REVIEWED PUBLICATIONS1. RA Malkin, “Physiological Measurements in the Developing World,”

invited review for Physiological Measurements.2. RA Malkin, “Design of Healthcare Technology for the Developing

World,” invited review for Annual Review of Biomedical Engineering3. R. A. Malkin, D. Guan, J Wikswo, “Experimental Evidence of Improved

Transthoracic Defibrillation Consistent with Electroporation” IEEE Trans on BME. 53(10), 2006, 1901-1911.

4. Malkin R. A., Jackson S., Nguyen J., Yang Z., Guan D., Experimental Verification of Theoretical Predictions Concerning the Optimum Defibrillation Waveform IEEE Trans BME v53(8), 2006, 1492-1498.

(See editorial comment concerning above paper, Krasteva, Kerkhof On the Optimal Defibrillation Waveform – How to Reconcile Theory and Experiment, IEEE Trans BME v53(8), 2006, 1725-1726.

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AND response concerning editorial comment, Malkin, Jackson, Mguyen, Yang, Guan, Replay to “On the Optimal Defibrillation Waveform – How to Reconcile Theory and Experiment” IEEE Trans BME v53(8), 2006, 1726-1727)

5. RA Malkin, “Engineering Humanity” Invited Editor of Special Edition, IEEE Medicine and Biology Magazine v25(3), 2006, 16-19.

6. BK Hoffmeister, AR Shores, S Banerjee, RA Malkin, Effect Of Electrically Insulating Materials On Magnetically Induced Electrical Currents In A Tissue-like Medium American Journal of Physics v74(4):260-266, 2006.

7. RA. Malkin, N Kramer., B Schnitz., M Gopalakrishnan, AL Curry, “Advances in Electrical and Mechanical Cardiac Mapping” Physiological Measurements, v26, 2005.

8. D Guan, R. A. Malkin, “Analysis of the Defibrillation Efficacy for 5-ms Waveforms” J Card. Electophys, vol. 15(4), 2004, 447-454.

9. Malkin, RA, Curry AD, Frequency Dependence of the Cardiac Threshold to Alternating Current Between 10 Hz and 160 Hz, Med Biol Eng Comp., 2003 v41(6), 640-645.

10.Exil VJ, Roberts RL, Sims H, McLaughlin JE, Malkin RA, Gardner CD, Ni G, Rottman JN, Strauss AW, “Very-Long-Chain Acyl-Coenzyme A Dehydrogenase Deficiency in Mice,” Circ Res, 93(5):448-55, 2003.

11.Schnitz, B A, Guan D, Malkin, R. A., “Design of an integrated sensor for in vivo simultaneous electrocontractile mapping,” 51(2), IEEE T Biomed Eng.

12.E Sylvester, B Hoffmeister, E Johnson, P Hess, RA Malkin, "Defibrillation causes immediate cardiac dilatation in humans," J Cardiovasc Electrophys. 14(8):832-6, 2003.

13.S. Roberts, D. Guan, R. A. Malkin, “The defibrillation efficacy of high frequency AC sinusoidal waveforms in guinea pigs” PACE 26(2) 599-604, 2003.

14.M. Gopalakrishnan, R. A. Malkin, "Two Dimensional Analysis of Ventricular Fibrillation in the Guinea Pig,” J Electrocardiology, v36(2), 147-153, 2003.

15.M. Malik, M. Gopalakrishnan, R. A. Malkin, “Quantifying the Spatiotemporal Effects of 2,3-Butanedione Monoxime (BDM) on Ventricular Fibrillation with a Conventional Mapping System” J Cardiovasc Eng, 2(3), 81-90, 2003.

16.de Jongh, V. Ramanathan, B. K. Hoffmeister, R. Malkin, “Left Ventricular geometry immediately following defibrillation: Shock-induced relaxation. Am J Physiol , v284, H815-H819, 2003.

17.R. Malkin “A large sample test of defibrillation waveform sensitivity,” J Cardiovasc Electrophys 13:361-370:2002.

(See editorial comment concerning above paper, CD Swerdlow, SF Lin, “Optimizing Defibrillation Waveforms,”

J Cardiovasc Electrophys, 13: 371-373: 2002.)18.J. Eason, N. M. Gades, and R. A. Malkin, " A Novel Technique to

Estimate Cardiac Geometry During Fibrillation," Physiol Meas v 23, 2002, 269-278.

19.R. A. Malkin, "An unconditional exact test for small samples of matched binary pairs,” J Modern App Stat. Methods, v1 (1) 2002, 69-73.

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20.E. Vigmond, N. Trayanova, R. Malkin, "Excitation of a cardiac muscle fiber by extracellularly applied sinusoidal current.” J Cardiovasc Electr. v12(10), 2001, 1145-1153.

21.R. A. Malkin and B. Hoffmeister, “The mechanism by which 60Hz AC currents cause hemodynamic collapse without inducing VF,” J Cardiovasc Electr . v12(10), 2001, 1154-1161.

(See editorial comment concerning above paper, E. Berbari, “The Shocking Truth,” J Cardiovasc Electr. v12(10), 2001, 1162-1163.)

22.R. A. Malkin, SR Smith, and BK. Hoffmeister, “The Geometry of the Heart Following Defibrillation,” Physiol Meas, v22(2), 2001. 309-321.

23.R. A. Malkin, R. Guinn and T. Mandrell, “Water soluble propofol anesthesia: An effective and inexpensive alternative,” Lab Anim, v29(9), 2000, 45-47.

24.J. Eason, R. A. Malkin, “A simulation study evaluating the performance of high density electrode arrays on myocardial tissue,” IEEE T Biomed Eng, v47(7), 2000, 893-901.

25.H. Li and R. A. Malkin, "An approximate Bayesian up-down method for estimating a percentage point on a dose-response curve," J App Stat, v 27(5), 2000, 579-587.

26.R. A. Malkin and B. Hoffmeister, "Hemodynamic Collapse, Geometry and the Rapidly Pacing on the Upper Limit of Vulnerability to fibrillation by T-wave stimulation," J Electrocardiol, v33(3), 2000, 279-286.

27.R. A. Malkin and Bradford Pendley, "Construction of a very high density extracellular electrode array," Am J Physiol., v279, H437-442, 2000.

28.R. A. Malkin, "Experimental Cardiac Tachyarrhythmias in Guinea Pigs," J Electrocardiol, v32 (supplement), 84-86, 1999.

29.J.N. Eynard and R. A. Malkin, "Open-Thorax Guinea Pig Model for Defibrillation," Lab Anim Sci. v49(6); 628-633, 1999.

30.R. A. Malkin, J. M. Herre, L. Mcgowen, M. Tenzer, J. R. Onufer, N. J. Stamato, M. Wood, and R. C. Bernstein, "A Four-Shock Bayesian Up-Down Estimator of the 80% Effective Defibrillation Dose," J Cardiovasc Electr, v10, pp973-980, July 1999.

31. Charles D. Swerdlow, Walter H. Olson, Mark E. O'Connor, Donna M. Gallik, Robert A. Malkin, and Michael Laks, “Cardiovascular Collapse Caused by Electrocardiographically Silent 60-Hz Intracardiac Leakage Current : Implications for Electrical Safety.” Circulation.1999;99;2559-2564.

(See editorial comment concerning above paper: MM Laks, R. Arzbaecher, D. Geselowitcz, JJ Bailey, A. Berson,

Revisiting the question: Will relaxing safe current limits for electromedical equipment increase hazards to patients?”

Circulation. 2000;v102:823-825.32.H. Li and R. A. Malkin, "Defibrillation and the Upper Limit of

Vulnerability to Fibrillation in a Transthoracic Guinea Pig Model," J Electrocardiol, vol. 32 (2) 1999, pages 159-166.

33.E. Entcheva, J. Eason, I. Efimov, Y. Cheng, R. A. Malkin, and F. Claydon, "Virtual Electrodes in Transvenous Defibrillation: Modulation by Structure and Interface: Evidence from Bidomain Simulations and Optical Mapping," J Cardiovasc Electr, 9, 949-961, 1998.

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34.R. A. Malkin and E. E. Johnson, "The Effect of Inducing ventricular fibrillation with 50Hz pacing versus T wave stimulation on the ability to defibrillate," PACE, 21(5), 1998, p 1093-1097.

35.R. A. Malkin, J. N. Eynard, N. F. Pergola, "Improved Guinea Pig Model of Cardiac Tachyarrhythmias," Lab Anim Sci, 48(1), 1998, p. 55-60.

36.R. A. Malkin, "Constructing a Multichannel Electrocardiography System from a Few Standardized, High Level Components," Eng Med Biol Mag, v17, January 1998, p. 34-38.

37.R. A. Malkin, J. E. Penzotti, S. P. Juhlin, and R. Plonsey, "Statistical Analysis of signals from an Intracavitary Probe in a Diseased Heart,” Med Biol Eng Comp,35, Sept. 1997, p. 462-466.

38.R. A. Malkin, J. J. Souza, and R. E. Ideker, "The Ventricular Defibrillation and Upper Limit of Vulnerability Dose-Response Curves," J Cardiovasc. Electr, 8, 1997, p. 895-903.

39.A. T. Compos, R. A. Malkin, and R. E. Ideker, "A Bayesian Up-Down Defibrillation Efficacy Estimator,'' PACE, 20, May 1997, p. 1292-1300.

40.R. A. Malkin, R. E. Ideker, and T. C. Pilkington, "Estimating Defibrillation Parameters Using Upper Limit of Vulnerability and Defibrillation Testing," IEEE T Biomed Eng, 43(1), January 1996, p. 69-78.

41.R. A. Malkin, S. F. Idriss, R. G. Walker, R. E. Ideker, "Effect of Rapid Pacing and T-Wave Scanning on the Relationship Between the Defibrillation and Upper Limit of Vulnerability Dose-Response Curves," Circulation, 92, 1995, p. 1291-1299.

42.J. J. Souza, R. A. Malkin, and R. E. Ideker, "Comparison of Upper Limit of Vulnerability and Defibrillation Threshold Parameters Probability of Success Curves Using a Nonthoracotomy Lead System," Circulation, 91(4), 1995, p. 1247-1252.

43.R. A. Malkin and D. Alexandrou, "Acoustic Classification of Abyssopelagic Animals," IEEE J of Oceanic Eng, 18(1), 1993, p. 63-72.

44.R. A. Malkin, T. C. Pilkington, D. S. Burdick, D. K. Swanson, E. E. Johnson, and R. E. Ideker, "Estimating the 95% Effective Defibrillation Dose," IEEE T Biomed Eng, 40(3), March 1993, p. 256-265.

PATENTSF. J. Callaghan, W. Vollman and R. A. Malkin, Patent Number 6,272,381 , August 7, 2001 "Rate-responsive pacemaker with closed loop control," assigned to Pacesetter, Inc.

BOOK CHAPTERS and EDITORSHIPS1. R.A. Malkin, Social Entrepreneurship for Biomedical Engineers in

Career Development in Bioengineering and Biotechnology, Springer (in progress)

2. R. A. Malkin, B Pendley, Electrodes in Cardiology: Theory and Practice, in Electrophysiology from Basic Science to Practice, Eds. Cabo., 2002, pg 259-289.

3. Annual Review of Biomedical Engineering, Annual Reviews, PaloAlto, CA, Eds. Yarmush, Diller, Toner, Malkin (guest), et al. 2002

4. R. A. Malkin, “Engineering Health Care Technology for use in the Developing World,” in Encyclopedia of Biomedical Engineering, Wiley, 2006.

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5. R. A. Malkin, A L Curry “Defibrillation - Theory and Instrumentation” in Encyclopedia of Biomedical Engineering, Wiley, 2006.

BOOKS

R. A. Malkin “Medical Equipment in the Developing World,” EWH Publishing, 2006.

EDITORIALS/ARTICLES ABOUT DR. MALKIN’s WORKKerkhof “On the Optimal Defibrillation Waveform – How to Reconcile Theory and Experiment”, IEEE Trans BME v53(8), 2006“Bangalore Boy Throws New Light,” The Times of India, 2006“Let There Be Light: New Low-cost alternative for neonatal jaundice,” Pediatric Archives August 2006“Ideas don’t have to cost an arm and a leg,” Independent Weekly, 2006“Socially-Minded Student Entrepreneurs Compete for Start Up Funds,” Duke-BME News Fall 2006 “Engineering World Health, An Innovative Model for Developing World Healthcare,” Duke Engineer, Spring 2006.“Jaundice project wins Duke Contest,” News and Observer, July 14, 2006“Prescription for Success,” IEEE Medicine and Biology Magazine, 2006“Engineers for the Developing World,” ABC11 TV story, May 22, 2006“The Incredibles,” ASEE Prism, March/April 2006“Businesses the Profit the World,” BusinessWeek Online, October 11, 2005.“Engineering Students offer aid in foreign Hospitals” The Chronicle, November 11, 2005. “Low-Tech, Cheap is their Goal: Duke Students tackle problems plaguing Third World Hospitals,” News and Observer October 2005“Engineering World Health” Duke BME News, Summer 2005“CUREs program”, News and Observer, Fall 2005“Student’s Corner: Engineering World Health,” IEEE Medicine and Biology Magazine, Jan/Feb 2004“Engineering World Health,” BMES Bulletin v27(1), 2003“Designing a Career in Biomedical Engineering” EMB-IEEE 2003“Engineering World Health, In Chemistry, Spring 2003Garrott, Kathy, “Cycle of caring changes lives,” Herff Highlights, Fall 2002.Drenning, Erin, “Retooling Rural Hospitals,” ASEE Prism, pg 44, October 2002.Russell, Greg, “Prescription for Success,” The University of Memphis Magazine, Spring 2002.Russell, Greg, “Fixing Parts, Saving Lives,” Memphis Magazine, v27(4) 2002.CD Swerdlow, SF Lin, “Optimizing Defibrillation Waveforms,” J Cardiovasc Electrophys, 13: 371-373: 2002.E. Berbari, “The Shocking Truth,” J Cardiovasc Electr. v12(10), 2001, 1162-1163.MM Laks, R. Arzbaecher, D. Geselowitcz, JJ Bailey, A. Berson, Revisiting the question: Will relaxing safe current limits for electromedical equipment increase hazards to patients?” Circulation. 2000;v102:823-825.Jones, T, “The heart of the matter,” The University of Memphis Magazine, Fall 2000.

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VIII. Bibliography

1. Chhatwal, L., et al., Cures Cold Box Business Plan. 2007, Duke University.2. SolarChill: The vaccine cooler powered by nature. 2005, United Nations Environment

Program.

IX. Appendix

Appendix 1: Intellectual Property

Patent Title: Polymer roof panel solar energy conversion deviceNumber: 7,234,303Date: June 26, 2007

This patent recommends the incorporation of recent advances in thermoplastics to increase the efficiency of solar panels. The panels are currently made out of glass, a material with poor insulation properties that allows some of the collected heat to leach out of the system before it has a chance to generate electricity. Using these new materials in the ‘solar chimney’ configuration to rotate a turbine, the author proposes an increase in energy conversion that will allow for smaller, more maneuverable panels.

Patent Title: Solar cell panel and solar energy collecting deviceNumber: 6,513,518Date: February 4, 2003

This patent outlines a design for solar cell panel construction. The design is akin to a sandwich design, in which the top layer is a front panel, such as glass, under which a network of fluid-types rests on top of an insulated backing (like foam). The sun’s radiation heats the fluid and eventually rotates a turbine to generate energy. An aluminum grille inserted into the tube layer can allow for more efficient heat transfer through its excellent conductive properties. The conducting fluid is circulated through the use of a pump. Such a device provides a means of producing energy without a stable electrical grid.

Patent Title: Rechargeable batteries based on nonconjugated conductive polymersNumber: 7,311,997Date: December 25, 2007

Nonconjugated conductive polymers are polymers that have doubles bonds which account for less than half of all bonds. These materials can be used in the cathodes of rechargeable batteries; they are rechargeable by external electrical sources. These materials allow new rechargeable batteries to be low weight and low cost. These batteries have a open circuit voltage of 1.25 volts. In a project where cost is a big concern, such a storage device could be extremely useful.

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Patent Title: Solar-powered lighting systemNumber: 7,249,863Date: July 31, 2007

This patent describes a system to operate Christmas tree lights using a solar cell panel to charge a battery, which is subsequently used to power the lights. Other notable features involve a photosensor to detect ambient light and an option to manually charge the battery. While intended for Christmas tree lights, this set-up is essentially what the project is searching for: energy collection and storage.

Patent Title: Solar panel unit and solar lamp including sameNumber: 5,467,257Date: November 14, 1995

The proposed invention details a solar panel mounted on a rotating frame that can maximize energy collection by tracking the sun throughout the day. The frame is powered by an electric motor (which is powered by the panel) and uses radiation sensors to detect the optimum position for collection. In relation to our project, it would be useful to see if tracking the sun will allow for an overall increase in energy collection. It needs to first be shown that the motor requires less power than it generates.

Patent Title: Omni directional baffled wind energy power converter apparatus and methodNumber: 7,287,954Date: October 30, 2007

This windmill differs from the tradition conception of such as its shaft is vertical to the ground and the blades are similarly oriented. The blades include baffles that can pick up wind from any direction and create torque in order to rotate the shaft. The design can supposedly operate in wide ranges of wind speeds, humidity, airborne debris, and temperature. For our project, we could perhaps use the shaft rotation to create an AC current (subsequently transformed to DC) that can provide power to the system. An added advantage is that wind power is always available and does not depend on cloud conditions as much as its solar cousin.

Patent Title: Helical wind rotor and a method for manufacturing the same Number: 6,428,275Date: August 6, 2002

This design, building on top of the Savonius-rotor (from Finland), involves two helical blades perpendicular to the shaft. This design is intended to catch and more efficiently utilize wind power than its predecessors by removing dead spots in the blades and collecting wind from more angles. The article also describes fabrication, which can be as easy as contorting a piece of plastic. For our project, such a simple fabrication method and large energy potential are very enticing and deserve further research.

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Patent Title: Flywheel-microturbine systemNumber: 6,169,390Date: January 2, 2001

This patent describes a power system which primarily uses a microturbine system and a flywheel to store some power as well as augment the turbine’s output. In the design, a high-speed permanent magnet is used as the starter for the microturbine. Once up to speed, the microturbine produces power to the load and the back-up source (fly wheel). A flywheel stores energy in the form of rotational inertia. By spinning at very high speeds, the weight of the flywheel contains enough inertia to generate an AC current through shaft rotation, which can later by rectified into a DC source. For our project, it may be useful to have a flywheel as a means to store energy for later when little energy can be collected. Its energy would always be available, but it is by no means a long-term substitute for continued energy collection. While not mentioned here, flywheels can be somewhat dangerous if they spin too fast and shatter, launching dangerous debris in all directions.

Title: Power generation method and power generator using a piezoelectric element, and electronic device using the powerNumber: 5,835,996Date: November 10, 1998

This patent offers a solution to powering portable electronic devices without tradiational electrical means. Usage of piezoelectric elements, as described in patent, can produce an appreciable voltage. Such a product could help meet the power requirements of the refrigerator. If this does in fact accomplish higher-efficiency power generation, our device will require less attention by the user in order to maintain the contents at a low temperature.

Title: Human powered electrical generation systemNumber: 6,281,594Date: August 28, 2001

This patent proposes that energy can be harnessed from normal human movements. Unlike past systems, the proposed design claims to be much more efficient and provide more power. If this claim is true, then perhaps we can have a clinic worker or villager provide the energy necessary for the refrigerator.

Title: Faraday FlashlightNumber: 7,229,188Date: June 12, 2007

This flashlight is powered by the operator shaking the device which in turn moves a magnet in a solenoid. If this technology could be ramped up to provide the necessary power for a cooling system, then this would be a relatively inexpensive and safe method of power generation. Whether or not the operators would understand and continue to shake the device to provide electricity is a cultural concern that must be examined.

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Appendix 2: Literature

Title: “Studies of the activated carbons used in double-layer supercapacitors”Author: Qu, D.Journal: Journal of Power SourcesYear Published: 2002 This article describes the construction and merits of carbon-based supercapacitors.  These devices can reach capacitances of 120 F/g.  Super capacitors consist of a strong liquid electrolyte between two conducting layers separated by very small distances (angstroms, in some cases).  The article also describes how movement towards super capacitor manufacturing has progressed in the last ten years.  With all capacitors, the discharge is very brief, so the team will have to compare this device's ability with our needs. 

Title: “Performance of a Magnetically Suspended Flywheel Energy Storage Device”Author: Ahrens, M., Kucera, L., and Larsonneur, R.Journal: IEEEYear Published: 1996  Recent development in material science has allowed for the manufacturing of lighter and stronger flywheels.  Combined with magnetic bearings, these devices can spin much more quickly and therefore store more energy.  The design in this paper includes a flywheel set-up able to output 1 kWh.  This is a sizeable amount of energy.  If such (or even cruded) kinetic energy devices exist, this may be a viable way to store energy for our system.

Title:  “Cost dynamics of wind power”Author: Neij, L.Journal: EnergyYear Published: 1999  This article's main purpose is to describe how wind-powered electricity will continue to cost less as improvements in implementation, design, grid integration, and lifespan come to light.  The paper predicts that the cost of wind energy will be halved by 2020.  While of no immediate importance to our project, it may be ultimately useful to develop a system whose cost will continue to decrease in the near future.  Furthermore, the article reviews applicable technologies, such as advances in turbine construction, fan design, and materials that can be instantly of use. 

Title: “Superconductivity, An Enabling Technology for 2 1 st Century Power Systems?”Author: Hassenzahl, W.V., Anal, A.E., Oakland, C.A.Journal: Applied SuperconductivityYear Published: 2001  Currently, over 2 billion people do not have access to a stable electricity grid necessary for, among other things, refrigeration.  This article describes how superconductors may rectify this problem by providing for a more efficient vehicle for electricity, as well as new technologies that target these 2 billion people.  Of special interest is the ability of

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superconductors to make advanced flywheel technology available to the larger public.  While the flywheel spins, it is suspended through superconducting bearings so as to reduce friction and minimize leakage.  If this product is available, it may be of interest to look into its application for our project. 

Title: “Solar-Gas Solid Sorption Refrigerator”Author: Vasiliev, L.L., Mishkinis, D.A., et alJournal: AdsorptionYear Published: 2001 From the abstract, "A solar refrigerator is made of a solar collector, adsorbed natural gas vessel (ANG), and compact, portable refrigeration system, which consists of two small adsorbers with heat pipe heat recovery system. An active carbon fiber "Busofit" saturated with different salts (CaCl2, BaCl2, NiCl2) is used as a sorbent bed and ammonia is used as a working fluid. The main particularity of this refrigerator is consumption of solar energy with methane gas burner as a back-up. The system management consists only in actuating the special type valves to change the direction of the heating circuit and water valves to change the water cooling circuit.".  Solar refrigerators are a current technology that is essentially pursuing the same goal as our team.   While far too large for our application, the article does provide lessons in selecting a cooling mechanism, power requirements, and energy collection/storage that may prove useful.

Title: “Solar Power in Africa: A Reality”Author: van der Plas, R.J., Hankins, M.Journal: Energy PolicyYear Published: 1998  This survey of solar power users in rural Kenya describes how they obtained their collection devices and their satisfaction with the system.  Of those polled, 60% were satisfied with their systems, while 94% of those polled would recommend it to a friend.  The most common power output of the system was 12 watt.   As shown in this article, rural Africans are generally pleased with solar power and would be likely accept a new system, such as ours, if it utilized solar energy. 

Title: “Application of thermoelectricity and photovoltaic energy to air conditioning”Author: Melero, A., Astrain, D., et alJournal: ThermoelectricsYear Published: 2003  The authors of this paper have designed a household air conditioning scheme that requires 1400 W and 48 Peltier units.  The entire system is powered by solar energy.  This project is much larger than ours, but the estimates and mathematics can be utilized to more accurately predict the minimum power that must be generated by our device. 

Title: “Flywheel batteries come around again”Author: Hebner, R., Beno, J., and Walls, A.Journal: IEEEYear Published: 2002This article provides an incredibly useful comparison between chemical batteries, flywheels, and SMES.  Flywheels have almost a 20 year lifespan, less environmental

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impact, and can hold energy for hours; all these things are advantages over the other two systems.  The flywheel is not, however, without its (literal) price.  Whereas batteries cost roughly 75$ per kilowatt, flywheels run about 600$ for the same amount of energy.  In terms of our projects, it will be necessary to see what kind of energy storage is required and which system makes the most sense.

Title: “Flywheel energy storage using superconducting bearings”Author: Abboud, R..G., Uherka, K., et alJournal: 56th annual American power conference Year Published: 1994This article demonstrates recent developments in flywheel technology including the invention of superconducting bearings, high tensile-strength materials from which the flywheel can be fabricated, and new electronics that allow more efficient energy conversion.  While our system may not apply some of these features (it takes a lot of energy to keep cyrogenic temperatures for superconducting bearings), it is worth noting that these technologies are being developed, and are becoming cheaper all the time.

Title: “Solar Thrill: Using the Sun to Cool Vaccines” Author: Burton, Journal: Environmental Health PerspectivesYear Published: 2007The SolarChill refrigeration system utilizes the power from three 60-watt solar panels to run a compressor that chills a compartment to form ice. The ice can then be moved into the vaccine chamber to keep medicines cool at night. While our project does not concern finding a refrigeration system, it is useful to know the approximate amount of energy we can expect a future refrigeration system to require. Also, this may be an example of using ice as a energy storage device.

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Appendix 3: Standards Analysis

Standard Test Procedure

Document WHO/PQS/E04/CB01.1 Vaccine cold box

4.2.1: Storage Capacity Will not meet; short range listed is 5-25L but specs require 1-2L

4.2.2: Cold life Procedure detailed in §3 4.2.5: Shape Visual inspection4.2.12: Vaccine storage advice

May not meet; info will be provided, but may not be able to translate into other languages

4.2.14: Corrosion resistance

May not meet; materials limited by available products and cost. Prototype materials will be researched to determine likelihood of corrosion.

4.2.15: Chemical resistance

May not meet; materials limited by available products and cost. Prototype materials will be researched to determine permissible disinfectants.

4.2.17: Robustness Will not meet; some materials (i.e. solar panel) may be too fragile and expensive to drop test

4.4.1: Weight May not meet; materials limited by available products and cost. Prototype will be weighed on a scale.

4.5.2: Dimensional compatibility with vaccine packaging

Will not meet; vaccine volume may be up to 6L but cavity is maximum 2L

4.5.3: Dimensional compatibility with transport mode

Test functionality after various means of transport (car, manual lifting/carrying)

4.10: Disposal and recycling

Provide information on hazardous materials and suggestions for disposal

4.11: Instructions Will not meet; user info will be provided in English, but translation to all listed languages is beyond project scope

8: On-site maintenance Note any required maintenance during prototype testing or anticipated maintenance

Document WHO/EPI/LHIS/97.06 Equipment performance specifications and test procedures, E3: refrigerators and freezers

RF.5: Temperature control

Procedures detailed in E3 general testing §1-9 and solar refrigerator §1-9

RF.5: Safe freezing capacity

Procedures detailed in E3 general testing §1-9 and solar refrigerator §1-9

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RF.5: No sun autonomyWill not meet; specifications for 19 hour rather than 72 hour autonomy; autonomy measured with procedures detailed in E3 general testing §1-9 and solar refrigerator §1-9

RF.5: Accessories and fittings

Will not meet; external reading thermometer provided but other accessories (fence, locking lid) outside of scope

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Appendix 4: Regulatory Analysis

Relevant Definitions

Active – An active device is defined as any medical device relying energy sources, except those devices that rely on gravity and those inherent in the human body. Furthermore, the device must connect the energy source and the human body; our project is merely to power a refrigerator, not energize the body, so this definition does not apply to our project.

Long term – The device is intended to for continuous use for more than 30 days. In fact, much more than 30 days; the device is designed for 3 years of continuous use.

Invasive – A device that penetrates the body. Our device does not.

Analysis

It is clear from Table 1 that our device is Class A. All tables are attached at the end of this section

Region Specific TestingThe testing required to ensure device compliance would have to be compared with

procedures outlined in GHTF’s Essential Principles of Safety and Performance of Medical Devices (SG1/N041). We have selected Tanzania as a representative country, due to its fairly robust regulatory process, for our region-wide device. Officially completing FDA regulations is a burdensome process that may take years for more invasive, dangerous devices. Luckily, our project is neither and so the pathway could be completed within a few months. As outlined in the GHTF document, our device is only tied to these applicable standards by its intended use. A requested Conformity Assessment would require the team to detail the usage and manufacturing techniques of the energy system. There are a variety of conformity regulations available through the GFTH, each with its own hurdles and pitfalls. In sum, the approval process would take some time (a few months) and require complete documentation.

FDA Regulation AnalysisOur device falls under the Class I umbrella, as determined by the classifications

set by the FDA General Device Classification Questionnaire: The device is not life-sustaining or life supporting The device is not of substantial importance in preventing impairment of human

health. The device does not present a potential unreasonable risk or illness or injury. There is sufficient information to determine that general controls are sufficient to

provide reasonable assurance of safety and effectivenessThe form for determining that our device is Class I was found at:

http://www.fda.gov/opacom/morechoices/fdaforms/FDA-3429.pdf.

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The refrigeration system is a Class I unapproved device being exported to a non-Tier I region after manufacture in the United States. As such, it falls under the jurisdiction of the 801 regulation; the 802 regulation is for more invasive and dangerous Class III devices. Analysis is included in Table 2.

Section 801(e)(1) allows for our device to be exported without FDA permission. Therefore, our device will follow the stipulations of Section 801(e)(1). Using Tanzania’s regulations as a representative case for the region, we have found that our device will not conflict with any standing importation regulations. The device operates on equipment already present in the area, thus eliminating one barrier. Furthermore, the product will be labeled for export only (after US-based manufacture) to prevent any issue with the FDA.

The FDA concerns itself with more invasive medical technologies, and is relatively silent on cold box manufacture and usage. One cold box already approved is the INRange Remote Medication Management System (K051338). This device includes everything needed to distribute and properly store medication a at a sub-clinical level: communication software, delivery method, and proper storage means. No document could be found that completely describes the product’s requirements, such as a need for temperature regulation, the expected storage time, etc. Thus, this approved product is only tangentially related to ours, but enough overlap exists such that we predict our product would receive 501(k) clearance.

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