streamlining & optimizing logistics and fleet management system

7/31/2019 Streamlining & Optimizing Logistics and Fleet Management System

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Summer Project Report

on

Streamlining & Optimizing Logistics and Fleet Management System

Undertaken At

ACC Concrete Limited

In Partial Fulfillment of Summer Internship of

Post Graduate Diploma in Industrial Engineering (PGDIE)

By

Amit Chauhan(Roll No. 8)

PGDIE Class of 2013

Procurement Officer (N&E) , Faculty, NITIEACC Concrete LimitedMumbai

Faculty, NITIE

NATIONAL INSTITUTE OF INDUSTRIAL ENGINEERING

VIHAR LAKE, MUMBAI 400 087


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Summer Internship 2012 | ACC Concrete Limited | NITIE, Mumbai |2

CERTIFICATE OF PROJECT COMPLETION

This is to certify that Mr. Amit Chauhan , a student of the Post Graduate Diploma inIndustrial Engineering (PGDIE), 41 st Batch of the National Institute of Industrial Engineering(NITIE), Mumbai has completed his summer project on


The Project was successfully completed under my guidance and supervision from the12th April, 2012 to 12th June 2012. We have derived immense benefit from the project andhis contribution to our organization is highly appreciated.

I hereby convey my best wishes to him for all his future endeavors.

Mr Balram ChakarwartiProcurement Officer (N&E)ACC Concrete Limited


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CERTIFICATE OF PROJECT COMPLETION

This is to certify that Mr. Amit Chauhan , a student of the Post Graduate Diploma inIndustrial Engineering (PGDIE), 41 st Batch of the National Institute of Industrial Engineering(NITIE), Mumbai has completed his summer project on


The Project was successfully completed under my guidance and supervision from the

12th April, 2012 to 12th June 2012. His hard work is deeply appreciated.

I wish him all the best in his future life.

Prof. T. Prasad

Faculty, NITIE Mumbai

Prof. Sumi Jha

Faculty, NITIE Mumbai


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ACKNOWLEDGEMENTS

Too often we are so preoccupied with the destination, we forget the guiding light.

-Anon

I take this opportunity to extend my sincere thanks to ACC Concrete Limited for offering aunique platform to earn exposure and garner knowledge in the field of logistics of supplychain.

I wish to extend my sincere and heartfelt gratitude to my guide Mr. Balram Chakarwarti,Procurement Ofiicer (N&E) , who guided, supported and encouraged me during the entiretenure of the project. I also thank Mr. Anil Banchhor, Vice President ,North EastOperations, for his co-operation and valuable advice throughout the course of my project.Also I would like to take this opportunity to thank Mr. Nirmal Singh for their supportthroughout the course of project. I am able to say with conviction that I have immenselybenefited from auspicious and prestigious association as a summer intern with CadburyIndia.

I also thank Prof. T. Prasad and Prof. Sumi jha , my faculty guide, who inspired me by hisdiscussions and showed me the right course to pursue.

I also wish to thank all people in the Head Office and the various plants of ACC ConcreteLimited for their constant support and help in accomplishing the objectives of the project.There are many who I may have left out in the acknowledgement, but whose co-operationno doubt went a long way in the project completion.

Amit Chauhan

PGDIE 41


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Executive Summary

ACC Concrete Ltd. is separated from its parent company ACC Cement in 2008 for more focusedapproach on Ready Mix Concrete(Ready-made Concrete) segment as RMC industry has shown 24%CAGR from year 2000 to 2006, consider as a high growth industry. ACCCL has formed itself as amajor player in the RMC industry. ACCCL sees to right from its inception in 2008 outsource itsoutbound Logistics service to around 75 medium & small size local contractors (around 80% aresmall contractors) on a contract basis of 2-3 years. Outbound logistics mainly comprises of deliveryof Concrete to the customer site. Logistics is a crucial operation as the delivery of concrete has to besynchronized with other activities and hence it adds to the dynamics of this operation. Not only thesite but exact time has to be kept in mind of the logistics officer as the shelf life of Concrete is just 3 hours. RMC transportation is unique as:

It is a Road transport Special Body of TM(Transit Mixer) difficult to use for other transports

Return Trips: Drum mixer is empty - 50% of total km traveled, No backhaul One load : one unloading point Operating Zone: 50-60 km around RMX plant

There are issues concerning traffic jam, non availability of TM, legal issues, reluctant nature of drivers. In the lean period contracted TM lies idle adding to the cost. A significant amount of breakdown hours due to improper maintenance of TM by contractor act as a bottleneck forcompany to deliver on time. To avoid risk ACC maintains a large fleet of TM at the plant increasinglogistics cost leading to substandard number of trips per day. The % of logistics cost is around 14 - 25% of the total cost of the Concrete (varies with the plant). Logistics Contract utilization is around 50%and dips to as low as 20% in lean season. With increasing customer expectation and very stringentprofit margin, ACCCL in its pursuit to achieve competitive advantage, needs to control allocation of production to different plants to serve different customers taking into consideration differentrelevant costs for decision making. It also wants to schedule its fleet such that optimum utilizationof resources can be done.

Thus the objective of this project is: Mathematical modeling for allocation of production in with minimum total cost Generating schedules for the fleet for each plant


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Table of Contents

Executive Summary............................................................................................ 5

Table of Contents ............................................................................................... 6

Table of Figures.................................................................................................. 7

1. Company Profile ............................................................................................. 8

1.1 RMC an overview ....................................................................................................................... 8

1.2 RMC Industry................................................................................................................................. 8

1.3 SWOT Analysis for RMC industry ................................................................................................ 10

1.4 About ACC & ACCCL ................................................................................................................... 11

1.5 ACCCL Vision & Mission .............................................................................................................. 14

1.6 ACCCL Ready Mix Concrete Plants: ............................................................................................. 16

3. Need & Objective of Project ......................................................................... 17

4. Literature Survey .......................................................................................... 18

5. Methdology ................................................................................................. 19

6. Modelling ..................................................................................................... 20

6.1 For Optimal Allocation of Production ........................................................................................ 20

6.2 For Scheduling ............................................................................................................................ 22

7 Cost Benefit Analysis ..................................................................................... 23

8 Future Scope ................................................................................................. 23

9 Limitations .................................................................................................... 23

10 Academic Contribution ............................................................................... 23

References ....................................................................................................... 24

Appendix I ........................................................................................................ 25

Appendix II ....................................................................................................... 30

Appendix III ...................................................................................................... 46


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Table of Figures

Figure 1 Showing comparison ............................................................................................................... 10Figure 2 Market Share ........................................................................................................................... 15Figure 3 Map showing plant location.................................................................................................... 16Figure 4 Input window .......................................................................................................................... 46Figure 5 Showing choosing plant of which want to see schedule ........................................................ 46Figure 6 Schedule For Pratibha plant .................................................................................................... 47Figure 7 Distance Matrix ....................................................................................................................... 47Figure 8 Truck Available Table .............................................................................................................. 48Figure 9 Mix Proportion Matrix ............................................................................................................ 48Figure 10 Material cost ......................................................................................................................... 49
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1. Company Profile

1.1 RMC an overview

Ready-mix concrete (RMC) is a ready-to-use material, with predetermined mixture of cement, sand, aggregates and water. RMC is a type of concrete manufactured in a factoryaccording to a set recipe or as per specifications of the customer, at a centrally locatedbatching plant.

It is delivered to a worksite, often in truck mixers capable of mixing the ingredients of theconcrete en route or just before delivery of the batch. This results in a precise mixture,allowing specialty concrete mixtures to be developed and implemented on construction sites.The second option available is to mix the concrete at the batching plant and deliver the mixedconcrete to the site in an agitator truck, which keeps the mixed concrete in correct form.

In the case of the centrally mixed type, the drum carrying the concrete revolves slowly so asto prevent the mixed concrete from "segregation" and prevent its stiffening due to initial set.

The use of the RMC is facilitated through a truck-mounted 'boom placer' that can pump theproduct for ready use at multi-storeyed construction sites. A boom placer can pump theconcrete up 80 meters.

RMC is preferred to on-site concrete mixing because of the precision of the mixture andreduced worksite confusion. It facilitates speedy construction through programmed deliveryat site and mechanized operation with consequent economy. It also decreases labour,site supervising cost and project time, resulting in savings. Proper control and economy in useof raw material results in saving of natural resources. It assures consistent quality throughaccurate computerised control of aggregates and water as per mix designs. It minimizescement wastage due to bulk handling and there is no dust problem and therefore, pollution-free.

1.2 RMC Industry

The Ready mix concrete business in India is in its infancy. Where as in developed countries,nearly 70 per cent of cement consumption is in the form of ready mix concrete and 25 percent in the form of recast, in India, ready mix concrete accounts for less than 5 per cent andas much as 82 per cent of cement consumption is in the form of site-mixed concrete. While70% of cement produced in a developed country like Japan is used by Ready Mix concretebusiness there, here in India, Ready Mix concrete business uses around 2% of total cementproduction.

There are several reasons for this. In early 70s both pricing and distribution of cement was

controlled due to shortage of supply. Ready mix concrete technology could not beimplemented as investors felt that Ready mix concrete plant will starve due to non-


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availability of cement. The levy of additional taxes & duties on RMC, entry tax, excise dutyalso contributed to the slow development of the concept.

The growth of RMC is predominantly driven by demand from the metro cities. In cities likeMumbai, the mandatory use of RMC is in construction of flyovers provided therequisite impetus to growth, according to an ICRA analysis. RMC is particularly useful whenthe building activity is located in congested sites where little space is available for sitting themixer and for stock piling of aggregates. The use of RMC is also advantageous when onlysmall quantities of concrete are required or when concrete is to be placed only at intervals.

Even as the concept of ready-mix concrete (RMC) is still catching up in the country, cementmajors are keenly focusing on entering the new area in a big way. Anticipating huge potentialfor the product, cement majors, including ACC, Grasim, L&T, India Cements, PriyadarshiniCements, Chettinad Cement and Madras Cements, are foraying into the RMC business andthe share of RMC is expected to go up from present levels of around 5 per cent of the totalcement production to the global average of 70 per cent, according to industry players.

For growth of the industry, government bodies, private builders, architects/engineers,contractors, and individuals required to be made fully aware about the advantages of usingready mix concrete, government bodies/consultants needs to include ready mix concrete asmandatory in their specification for execution, government specifications for CPWD andPWD jobs should include Ready mix concrete as a mandatory item. Apart from this taxbreaks are required for the growth of RMC and developers/contractors needs to bediscouraged from piling up materials like metal, sand etc. on roads/foot paths.

Advantages of Ready mix Concrete over Site mix Concrete

A centralised concrete batching plant can serve a wide area The plants are located in areas zoned for industrial use, and yet the delivery trucks can

service residential districts or inner cities Better quality concrete is produced Elimination of storage space for basic materials at site Elimination of procurement / hiring of plant and machinery Wastage of basic materials is avoided Labour associated with production of concrete is eliminated Time required is greatly reduced Noise and dust pollution at site is reduced Reduce cost


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Limitation of Ready mix Concrete

The materials are batched at a central plant, and the mixing begins at that plant, so thetravelling time from the plant to the site is critical over longer distances. Some sitesare just too far away, though this is usually a commercial rather than technical issue.

Current user segments for Ready mix Concrete

Residential Complex (Flat) promoters Large Construction Company engaged in infrastructure & industrial projects Small and medium contractors engaged in housing & commercial buildings

Share of various segment in RMC consumption

Infrastructure forms the major customers of RMC Industrywith share of 38% in 2010 & hike of 10% in overall RMCdemand

1.3 SWOT Analysis for RMC industry

Strengths India is second largest producer of cement in the world in terms of capacity, cement is

a major component of RMC Low cost of production as compared to other substitute methods Abundance of other raw material (fine & coarse aggregate) Strong Sales & distribution network Good connectivity of roads to deliver concrete in Urban & Semi-Urban areas

Weakness Demand supply Gap, overcapacity & high inventory Increasing cost of labours

High Interest rates No tax rebate/subsidy from government

Figure 1 Showing comparison


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Opportunities Strong growth of economy in the long run Increase in infrastructure projects in India

Growing middle class income & housing demand Technological changes Increase in government spending

Threats Fluctuations in cement prices Excess overcapacity can hurt margins as well as prices Entry of new players Effect of global recession on Real Estate & Infrastructure

1.4 About ACC & ACCCL

ACC (ACC Limited) initially termed as Association of Cement Companies, is the oldestcement & concrete in India. ACC's operations are spread throughout the country with 16modern cement factories, more than 40 Ready mix concrete plants, 20 sales offices, andseveral zonal offices. It has a workforce of about 10,000 persons and a countrywidedistribution network of over 9,000 dealers. ACC has made significant contributions to the

nation building process by way of quality products, services and sharing expertise. Itscommitment to sustainable development, its high ethical standards in business dealings andits on-going efforts in community welfare programmes have won it acclaim as a responsiblecorporate citizen. ACCs brand name is synonymous with cement and enjoys a high level of equity in the Indian market. It is the only cement company that figures in the list of ConsumerSuper Brands of India.

Major Milestones:

1936 Incorporation of The Associated Cement Companies Limited on August 1,1936.

1937 With the transfer of the 10th company to ACC, viz. Dewarkhand CementCompany, the formation of ACC is complete on October 23, 1937.

1947 Indias first entirely indigenous cement plant established at Chaibasa inBihar


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1956 Bulk Cement Depot established at Okhla, Delhi

1961 Blast furnace slag from TISCO used at the Chaibasa Unit to manufacturePortland Slag Cement for the first time in India.

1961 Manufacture of Accocid Cement, which resists the corrosive action of acidsand chemicals.

1961 Manufacture of Hydrophobic (waterproof) cement at ACC Khalari CementWorks in Bihar.

1962 Manufacture of Accoproof, a waterproofing additive.

1965 ACCs Central Research Station (CRS) established at Thane

1965 Manufacture of Portland Pozzolana Cement.

1968 ACC supplied and commissioned one-million-tone iron ore pelletizing plantordered by TISCO

1973 Take-over of The Cement Marketing Company of India (CMI)

1979 ACC wins international contract for operation and management of a new one

million tone cement plant at Yanbu-Ras Biridi in Saudi Arabia.

1982 Commissioning of the first 1 MTPA plant in the country at Wadi, Karnataka.

1992 Incorporation of Bulk Cement Corporation of India, a joint venture with theGovernment of India.

1993 ACC starts the commercial manufacture of Ready Mixed Concrete atMumbai.

1999 Tata group sells 7.2% of its stake in ACC to Ambuja Cement Holdings Ltd,a subsidiary of Gujarat Ambuja Cements Ltd. (GACL)

2000 Tata Group sells their remaining stake in ACC to the GACL group, whowith 14.45% now emerge as the single largest shareholder of ACC.

2002 ACC wins PHDCCI Good Corporate Citizen Award

2004 ACC named as a Consumer Superbrand by the Superbrands Council of

India, becoming the only cement company to get this status.


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2004 GreenTech Safety Gold and Silver Awards awarded to Madukkarai CementWorks and Katni Refractory Works by Greentech Foundation foroutstanding performance in Safety Management System.

2005

Holcim group of Switzerland enters strategic alliance with Ambuja Groupby acquiring a majority stake in Ambuja Cements India Ltd. (ACIL) whichat the time held 13.8 % of the total equity shares in ACC. Holcimsimultaneously makes an open offer to ACC shareholders, through HoldcemCement Pvt. Limited and ACIL, to acquire a majority shareholding in ACC.Pursuant to the open off er, ACILs shareholding in ACC increases to 34.69% of the Equity share capital of ACC.

2006 Change of name to ACC Limited with effect from September 1, 2006 fromThe Associated Cement Companies Limited.

2006 ACC receives Good Corporate Citizen Award 2005-06 from BombayChamber of Commerce and Industry

2006 New corporate brand identity and logo adopted from October 15, 2006

2008 Ready mixed concrete business hived off to a new subsidiary calledACC Concrete Limited.

2008 ACC wins CNBC-TV18 India Business Leader Award in the category IndiaCorporate Citizen of the year 2008

2009 ACC received the Jamanalal Bajaj "Uchit Vyavahar Puraskar" of Council forFair Business Practices

2010 ACC acquires 100 percent of the financial equity of Encore Cements &Additives Private Limited which is a slag grinding plant in Vishakhapatnamin coastal Andhra Pradesh. This company became a wholly-ownedsubsidiary of

2012 ACCCL developed self compacting M100 grade concrete with high towerpumping capability


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1.5 ACCCL Vision & Mission

VisionTo be trusted and respected partner , creating value for all stakeholders, in a sustainable manner.

MissionTo be leader in providing quality concrete solutions to targeted markets, on time and creatingcustomer delight.

Strength be a respected partner through trust and openness Integrity in everything we do An agile organization with global leadership and competence Effectiveness through competence Continuous improvement through innovation

Performance Adding value by delivering on our promises to each other and to our stakeholders Best solutions for our customers and become the supplier of choice Competitiveness through excellence in all spheres Focussed business decisions through ownership and accountability

Passion Dedication and commitment- we care about everything we do

o We care about our people, their safety and their developmento We care about our customers, stakeholders and their successo We care about our world, in particular the communities we live and work in

Energising & inspiring others through leading by example ,timely recognition andcelebrating success

We take pride in performing well

ACC set up India's first commercial Ready Mix Concrete (RMX) plant in Mumbai in 1994which together with the promotion of bulk cement has played a key role in redefining the

pace and quality of construction activity in our large cities and mega infrastructure projects.

The Ready Mix Concrete business of ACC was reorganized as a separate wholly ownedsubsidiary which was incorporated as ACC Concrete Limited with headquarters in Mumbai.Today this company is one of the largest manufacturers of Ready Mix Concrete in India witha countrywide network of over 30 plants, with modern equipment and a large fleet of transitmixers.


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Major Competitors in Delhi Region:

Lafarge

Ultratech Ashtech

ACCCL Offerings to customers:

It offers solutions under two broad categories:

Concrete solutions Ready Mixed concrete Special concretes Customized / specified concrete

Services Value Added services Vendor managed inventory Onsite batching plants under various working models

10%

17%

17%

10%

47%

1,811

Pan India

13%

5%8%4%

71%

411

11%

8%

25%

24%

9%

35%

311

Mumbai

8%

Chennai

ACCCL

Lafarge

Ultratech

RMC(I)

Others

5%

13%

5%

69%

230

Hyderabad

33%

10%

13%

33%

Delhi

66

Kolkata

6%

15%

13%

13%

54%

133

ACCCL market share across regions for Dec 09Volumes in 000 m3

Figure 2 Market Share


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1.6 ACCCL Ready Mix Concrete Plants:

ACCCL has its presence in all the major concrete consumption areas in India. A locationoverview of RMC plants can be seen below:

Figure 3 Map showing plant location


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3. Need & Objective of Project

Need

As the number of customers and grades of concrete is increasing , it is quite cumbersome forhumans to overcome the problem of allocating different resources like plants and trucks to differentcustomers. Also as serving customers is restricted by distance factor also , there is net of plants insmaller area. There are local vendors for raw materials for each plant, therefore causing a pricedifferential among plants. So, there is need for a tool that can optimally allocate customers to plantsand also find how much quantity is produced at a plant for a customer ( as a customer may beserved by multiple plants ).

It is also a problem that one plant has spare truck at times when other plant is in shortage and notable to make due timing. The automatic generation of fleet schedule is also needed for fasterdecision making. The company needs tool that can help identify customers which most probably willbe served late, so that marketing department renegotiate on time and increase customersatisfaction.

Objective

o Identification of relevant cost for multiplant production allocation decision makingo Developing a mathematical model for optimization of production allocationo Facilitating interplant truck transfero Schedule generation for fleet to meet customers due timeo Help in improving service quality by facilitating time negotiations


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4. Literature Survey

A key problem managers face is how to allocate scarce resources among various activities orprojects. Linear programming, or LP, is a method of allocating resources in an optimal way. It is oneof the most widely used operations research tools and has been a decision making aid in almost allmanufacturing industries and in financial and service organizations.

In contemporary market, people prefer to products with best quality at the lowest prices, regardlessof where they are produced. Hence, most companies can no longer afford to produce their productsin a single plant to provide the products needed with the lowest production cost in the market . Toget the edge of competitive strategy, several studies suggest that firms should transfer productionto locations for lowing production cost and maximizing total production quantities in a whole whilemaintaining quality and reliability.

Production planning process in a multi-plant facility is a large-scale problem that many industrieswith complex operations face on a continual basis and different computational models have beenproposed. Bhatnagar and Chandra defined the property of a coordinated multi-plant productionplanning problem as seeking to link together the production plans of hierarchical integratedmanufacturing plants. In other words, the objective of coordination is to achieve better performancefor the entire network, such as minimizing total relevant costs, improving service quality etc. Variousmathematical models are proposed for such optimization problems under linear programming,Integer programming etc.

In the term linear programming, programming refers to mathematical programming. In this context,

it refers to a planning process that allocates resources labor, materials, machines, capital in thebest possible (optimal) way so that costs are minimized or profits are maximized. In LP, theseresources are known as decision variables . The criterion for selecting the best values of the decisionvariables (e.g., to maximize profits or minimize costs) is known as the objective function . Limitationson resource availability form what is known as a constraint set .

Transportation cost represents approximately 40 to 50 percent of total logistic costs and 4 to 10percent of the product-selling price for many companies. As such, transportation decisions directlyaffect the total logistic costs. Transportation is an important component of supply chaincompetitiveness since it plays a major role in the inbound, inter-facility, and outbound logistics. In

this context, assigning and scheduling vehicle is a crucial management problem.

It can be easily noted that the just-in-time supply problem considered here also shares manycommon aspects with a large number of related logistic problems that have been considered intechnical literature. For instance, the assignment of trucks for transportation can be modelled as avehicle routing problem (VRP), which is among the most thoroughly investigated problems of operations research. The version of the VRP more related to our case study concerns the routing of afleet of vehicles with time-window constraints and is known as Multi-Depot Multi-Vehicle RoutingProblem with Time Windows. The nearly prohibitive combinatorial complexity of this problem makesanalytical approaches impracticable, especially for cases of a size comparable to our problem. Thus,available literature focuses on heuristic approaches capable to achieve satisfactory solutions in

acceptable times.


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5. Methdology

The methodology being followed in project development is shown in figure below.

1. Understand the scope and objectives of the project

The requirements of the project are analysed thoroughly in order to plan execution plan.

The boundaries of the project are defined that what it should include and what it should not.

2. Data collection

Firstly, the relevant data for this project is identified. Then, data is collected from differentconcernced authorities. For example, logistics related data from logistics officer and rawmaterials data from procurement data etc.

3. Understand System Constraints

The different constraints like capacity constraint, requirement fulfil constraint. Forscheduling number of TMs , speed in peak hour and non-peak hour etc are considered.

4. Develop Mathematical model for optimal allocation

Linear programming model is developed and implemented using open solver as it has 400decision variables with an objective of minimum total cost.

5. Develop fleet schedules

Scheduling algorithm is designed such that it will schedule trucks according to customer duetime and propose schedule for customers it wont able to serve on time due to limiting

trucking capacity.

Understand the scope andobjective of the project

Data Collection

Understand Systemconstraints

Develop Mathematicalmodel for optimal allocation

Develop fleet schedules

Test and rectify errors


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6. Test and rectify errors

The macros being developed are prone to errors and therefore testing of the developedtool should be done in order minimize errors while usage. In this phase, anyimprovement suggested by mentor can also be incorporated.

6. Modelling

ACCCL manages a fleet of TM (Transit Mixer) & Pumps for delivery of RMC at the customer site. Fleetmanagement is one of the important operations of ACCCL. Fleet management is a basic need for

following reasons:

1. Efficient Delivery at customer end

2. Availability of equipment, technical excellence & service availability

6.1 For Optimal Allocation of Production

Assumptions

o Total cost comprises of raw materials cost and logistics costs only. As other costs arenot relevant to this decision making.o Logistics cost is calculated on the basis of distance and average speed and it doesnt

take into consideration the condition of route between plant and customers.

Objective Function

The objective function is the minimizing total cost. Here total cost is sum of logistics cost and rawmaterial cost. This are relevant costs for this , as raw material is procured from local vendors

User Input Front End

OpenSolver

SchedulingMacro


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therefore different raw material prices. Logistics cost is directly proportional to distance betweenplant and customer site.

Minimize : Total Cost

Or

Minimize

Constraints

Capacity constraint Each plant has some fixed production capacity above which plant may not able to produce even if demands exceeds. So, capacity of plant is the constraint.

For each plant p,

Demand Fullfillment constraint

The demand of each customer should be fulfilled. As it is minimization problem , if this constraint ismissing it will allocate zero to all plants and even negative if non-negative constraint is missing.

For each customer r,

Maximum Distance served Constraint

As the shelf life or concrete has only 3.5 hours after adding admixture, it constrain plants to servecustomers. As only geographical vicinity plant can serve. This creates needs to add constraint of maximum distance of customer a plant can serve.

Dist(p,r) = Dist(p,r) if Dist(p,r)


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For all p and r , Allocate(p,r) >=0

Dist(p,r) >= 0

We suppose that at a given decision time, R (request) demands from different customers have beenreceived, and have to be assigned to P (plants) different PCs. Thus, we introduce the following

indices:

p {1,,D}Plant-related index.

r {1,,R}, customer or demand -related index.

h {1,,H} Grade of concrete-related index.

l {1,,L} raw material component-related index.

Average : It represents the average speed of the TM .

Rate : It is the price of diesel per litre.

Distance(p,r) : It represents distance of plant p and customer r.

CEIL(x,y) : It is function that returns value equal or greater than x such that x is multiple of x. Greater

than x is the next multiple of y greater than x. For example, if x=32 y=7 then CEIL(x,y)=35

Allocate(p,r) : It is production allocated to plant p for serving customer r.

Ratio(h,l) : It represents quantity of material required for one cubic metre where grade of concrete h

and l component of raw material.

Price(l,r) : It represents price of raw material l at plant r.

6.2 For Scheduling

The following algorithm is used for scheduling :

Step 1 : Sort the list of customers on the basis of due time in ascending order. In order to serve inFCFS basis.

Step 2 : Now for each plant i , repeat steps 3 to 9

Step 3 : Now for each costomer j , repeat step 4 to 9


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Step 4 : Check whether this customer j is served by plant i. If yes, go to step 5 and if No, go to step 3

Step 5 : Calculate number of trips by using allocated production .

Step 6 : Now for each trip n to 1 , reapeat step 7 to 9

Step 7 : Check whether it is first shipment from plant i to customer j, if yes, go to step 8 else to 9

Step 8 : Chech whether TM is available or not, if available schedule by calculating dispatch timingbased on due time else schedule it when Tm will available and notify user about it.

Step 9 : Chech whether TM is available or not, if available schedule by adding batching time inprevioustruch dispatch time else schedule it when Tm will available and notify user about it.

7 Cost Benefit Analysis

Presently the company is storing data of distance from serving plant only. Therefore , data isunavailable for comparison point of view. But it will surely save cost of serving customers and alsoreduce time for preparing daily production schedule for each plant.

8 Future Scope

In future , constraints of type of road can also be added. Also it can be further modified to be usedby marketing people for quoting prices. It can further be develop to absorb if truck delays and makean alternate schedule for it.

9 Limitations

It is isolated Excel Application and not connected to any database in backend

therefore raw material data need to changed manually. OpenSolver is required for it to work.

10 Academic Contribution

Practical application of Linear Programming in industry Exposure to Solver and opensolver Modelling in Excel using Macros Hands-on experience on SAP Logistics Operations/Principles


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References

[1]Bhatnagar R., Chandra P., and Goyal S.K., Models for MultiPlant Coordination, European Journal of Operations Research , vol. 67, no. 2, pp. 141-160, 1993

[1] C. Canel and B. M. Khumawala, Multi-period international facilities location: An algorithm and

application, International Journal of Production Research, Vol.35, No.7, pp.1891-1910, 1997

[2] M. A. Cohen and H. L. Lee, Resource development analysis of global manufacturing anddistribution networks, Journal of Manufacturing and Operations Management, Vol.2, pp.81-104,1989.

[3] P. Haug, An international location and production transfer model for high technology

multinational enterprises, International Journal of Production Research, Vol.30, No.3, pp.559-572,1992.

[4] Shah N., Single and Multisite planning and scheduling : current status and futurechallenges, in Proceedings of AIChE Symposium Series , Foundations of computer AidedProcess Operations (FOCAPO98), Snowbird, USA, pp.75 -90, 1998

[5] V. Verter and C. Dincer, An integrated evaluation of facility location, capacity acquisition, and

technology selection for designing global manufacturing strategy, European Journal of Operational

Research, Vol.60, pp.1-18, 1992.


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Appendix I

Code for Scheduling from one plant :

Sub scheduling_1()

Dim TM_available As Integer

Dim TM_left As Integer

Dim cust_range As Range

Dim differnce_range As Range

Dim batching_time As Variant

Dim counter As Integer

Dim truck_number As Integer

Dim min_range As Range

Dim min_arrival As Double

Dim cust_name As Range

Dim crit_range As Range

Dim match_range As Range

Dim row_num_min As Variant

batching_time = Worksheets("Trucks Available").Range("C27").Value

TM_available = Worksheets("Trucks Available").Range("E4").Value

'Worksheets("Sheet1").Range("B3").Value = TM_available

Set cust_range = Worksheets("Dynamic Data Scheduling").Range("C179:C203")

Set difference_range = Worksheets("Dynamic Data Scheduling").Range("C209:C233")

Set cust_name = Worksheets("Dynamic Data Scheduling").Range("A209:A233")

counter = 0

TM_left = TM_available

Worksheets("sheet1").Range("A1").Value = TM_available

Worksheets("sheet1").Range("A2").Value = TM_left


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Set crit_range = Worksheets("Sheet1").Range("M2:M3")

'DELETING PREVIOUS OUTPUT

Worksheets("Sheet1").Select

Range("A4:D100").Select

Selection.ClearContents

Worksheets("sheet1").Range("B3").Select

For i = 1 To 25 'for plant 1 to check for each customers

If WorksheetFunction.IsNA(cust_range.Cells(i, 1)) = False Then ' to check whether served or not by

this plant

number_trips = Worksheets("Trips").Range("C4:C28").Cells(i, 1).Value ' if served trips required

For j = 1 To number_trips 'counter for number of trips made

ActiveCell.Offset(1, 0).Select ' for new row feed

If TM_left > 0 Then ' check whether TM is available for dispatching or not

If j = 1 Then ' if first first trip and first time already calculated in sheet

If counter = 0 Then

ActiveCell.Value = cust_range.Cells(i, 1) ' getting value from that sheet

ActiveCell.Offset(0, 1).Value = 2 * (difference_range.Cells(i, 1) / 1440) +ActiveCell.Value

ActiveCell.Offset(0, 2).Value = 0

ActiveCell.Interior.ColorIndex = 3

' truck_number = WorksheetFunction.Floor(counter / (TM_available), 1)

counter = counter + 1

ActiveCell.Offset(0, -1).Value = counter ' column a value

ActiveCell.Offset(0, 4).Value = cust_name.Cells(i, 1).Value ' column F value

TM_left = TM_left - 1

Else

ActiveCell.Value = cust_range.Cells(i, 1) ' getting value from that sheet


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For k = 1 To counter - 1

If Worksheets("Sheet1").Cells(3 + k, 3).Value < ActiveCell.Value &Worksheets("sheet1").Cells(3 + k, 4).Value = 0 Then

TM_left = TM_left + 1

Worksheets("Sheet1").Cells(3 + k, 4).Value = 1

End If

Next k

ActiveCell.Offset(0, 1).Value = 2 * (difference_range.Cells(i, 1) / 1440) +ActiveCell.Value




' ActiveCell.Offset(0, -1).Value = truck_number ' column a value





End If

Else ' if 2 or more trips

ActiveCell.Value = ActiveCell.Offset(-1, 0).Value + (batching_time / 1440) 'adding batchingtime for finding subsequent truck timing

For k = 1 To counter - 1

If Worksheets("Sheet1").Cells(3 + k, 3).Value < ActiveCell.Value &Worksheets("sheet1").Cells(3 + k, 4).Value = 0 Then

TM_left = TM_left + 1

Worksheets("Sheet1").Cells(3 + k, 4).Value = 1

End If

Next k


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ActiveCell.Offset(0, 1).Value = 2 * (difference_range.Cells(i, 1).Value / 1440) +ActiveCell.Value




' ActiveCell.Offset(0, -1).Value = truck_number 'column a value





End If

Else ' no truck available

' when no truck is available in the plant then we should look for earliest truck that will come

in premises to schedule

Set min_range = Worksheets("Sheet1").Range(Cells(3, 4), ActiveCell.Offset(-1, 5))

Set match_range = Worksheets("Sheet1").Range(Cells(4, 5), ActiveCell.Offset(-1, 3))

' min_arrival = Application.DMin(min_range, C3, criteria_range)

min_arrival = WorksheetFunction.DMin(min_range, Worksheets("Sheet1").Range("E3"),Worksheets("sheet1").Range("N2:N3"))

' checking condition for if no truck available then whether comes late or early for furtherdelivery

If j = 1 Then

If (min_arrival / 10000) > cust_range.Cells(i, 1).Value Then

MsgBox ("Customer " & cust_name.Cells(i, 1).Value & " can not be served on timewith present trucks")

ActiveCell.Value = (min_arrival / 10000) + (batching_time / 1440)


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Else

ActiveCell.Value = cust_range.Cells(i, 1)

End If

Else

If (min_arrival / 10000) < ActiveCell.Offset(-1, 0) + (batching_time / 1440) Then

ActiveCell.Value = ActiveCell.Offset(-1, 0) + (batching_time / 1440)

Else

ActiveCell.Value = (min_arrival / 10000) + (batching_time / 1440)

End If

End If

ActiveCell.Offset(0, 1).Value = 2 * (difference_range.Cells(i, 1).Value / 1440) +ActiveCell.Value





row_num_min = Application.Match(min_arrival, match_range, 0)

ActiveCell.Offset(-counter + row_num_min, 2).Value = 1

End If

Next j

End If

Next i

End Sub


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Appendix II

Code for Ouput Data :

Sub writing_output()

Dim plant_num As Variant

ActiveWorkbook.Worksheets("Output").Select

plant_num = Worksheets("Output").Range("B1").Value

If plant_num = 1 Then

Sheets("Sheet1").Select

Range("A4:A100").Select

Selection.Copy

Sheets("Output").Select

Range("A4").Select

Selection.PasteSpecial Paste:=xlPasteValuesAndNumberFormats, Operation:= _

xlNone, SkipBlanks:=False, Transpose:=False


Range("G4:H100").Select

Application.CutCopyMode = False

Selection.Copy


Range("B4").Select




Range("F4:F100").Select


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Selection.Copy


Range("B4").Select

Selection.PasteSpecial Paste:=xlPasteValues, Operation:=xlNone, SkipBlanks _

:=False, Transpose:=False

End If




Selection.Copy


Range("A4").Select






Selection.Copy


Range("B4").Select






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Selection.Copy


Range("B4").Select



End If




Selection.Copy


Range("A4").Select






Selection.Copy


Range("B4").Select





Selection.Copy



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Range("B4").Select



End If




Selection.Copy


Range("A4").Select






Selection.Copy


Range("B4").Select





Selection.Copy


Range("B4").Select



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End If




Selection.Copy


Range("A4").Select






Selection.Copy


Range("B4").Select





Selection.Copy


Range("B4").Select



End If


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Selection.Copy


Range("A4").Select






Selection.Copy


Range("B4").Select





Selection.Copy


Range("B4").Select



End If



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Selection.Copy


Range("A4").Select






Selection.Copy


Range("B4").Select





Selection.Copy


Range("B4").Select



End If





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Selection.Copy


Range("A4").Select






Selection.Copy


Range("B4").Select





Selection.Copy


Range("B4").Select



End If




Selection.Copy



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Range("A4").Select






Selection.Copy


Range("B4").Select





Selection.Copy


Range("B4").Select



End If




Selection.Copy


Range("A4").Select



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Selection.Copy


Range("B4").Select





Selection.Copy


Range("B4").Select



End If




Selection.Copy


Range("A4").Select





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Selection.Copy


Range("B4").Select





Selection.Copy


Range("B4").Select



End If




Selection.Copy


Range("A4").Select







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Selection.Copy


Range("B4").Select





Selection.Copy


Range("B4").Select



End If




Selection.Copy


Range("A4").Select






Selection.Copy



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Range("B4").Select





Selection.Copy


Range("B4").Select



End If




Selection.Copy


Range("A4").Select






Selection.Copy


Range("B4").Select



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Selection.Copy


Range("B4").Select



End If




Selection.Copy


Range("A4").Select






Selection.Copy


Range("B4").Select





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Selection.Copy


Range("B4").Select



End If




Selection.Copy


Range("A4").Select






Selection.Copy


Range("B4").Select





Selection.Copy


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Range("B4").Select



End If

End Sub


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Appendix III

Snapshots of Excel Tool :Input GUI for data input. This is the data which frequently needs to be changed. Rest data is in othersheets which needs to be changed infrequently.

Figure 4 Input window

The following figures shows optimal allocation and schedule for pratibha plant.

Figure 5 Showing choosing plant of which want to see schedule


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Figure 6 Schedule For Pratibha plant

Figure 7 Distance Matrix


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Figure 8 Truck Available Table

Figure 9 Mix Proportion Matrix


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Figure 10 Material cost

streamlining & optimizing logistics and fleet management system

Documents