Search results for: convenient shop
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 667

Search results for: convenient shop

637 Schedule a New Production Plan by Heuristic Methods

Authors: Hanife Merve Öztürk, Sıdıka Dalgan

Abstract:

In this project, a capacity analysis study is done at TAT A. Ş. Maret Plant. Production capacity of products which generate 80% of sales amount are determined. Obtained data entered the LEKIN Scheduling Program and we get production schedules by using heuristic methods. Besides heuristic methods, as mathematical model, disjunctive programming formulation is adapted to flexible job shop problems by adding a new constraint to find optimal schedule solution.

Keywords: scheduling, flexible job shop problem, shifting bottleneck heuristic, mathematical modelling

Procedia PDF Downloads 366
636 Decision Tree Based Scheduling for Flexible Job Shops with Multiple Process Plans

Authors: H.-H. Doh, J.-M. Yu, Y.-J. Kwon, J.-H. Shin, H.-W. Kim, S.-H. Nam, D.-H. Lee

Abstract:

This paper suggests a decision tree based approach for flexible job shop scheduling with multiple process plans, i. e. each job can be processed through alternative operations, each of which can be processed on alternative machines. The main decision variables are: (a) selecting operation/machine pair; and (b) sequencing the jobs assigned to each machine. As an extension of the priority scheduling approach that selects the best priority rule combination after many simulation runs, this study suggests a decision tree based approach in which a decision tree is used to select a priority rule combination adequate for a specific system state and hence the burdens required for developing simulation models and carrying out simulation runs can be eliminated. The decision tree based scheduling approach consists of construction and scheduling modules. In the construction module, a decision tree is constructed using a four-stage algorithm, and in the scheduling module, a priority rule combination is selected using the decision tree. To show the performance of the decision tree based approach suggested in this study, a case study was done on a flexible job shop with reconfigurable manufacturing cells and a conventional job shop, and the results are reported by comparing it with individual priority rule combinations for the objectives of minimizing total flow time and total tardiness.

Keywords: flexible job shop scheduling, decision tree, priority rules, case study

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635 A Mathematical Model for a Two-Stage Assembly Flow-Shop Scheduling Problem with Batch Delivery System

Authors: Saeedeh Ahmadi Basir, Mohammad Mahdavi Mazdeh, Mohammad Namakshenas

Abstract:

Manufacturers often dispatch jobs in batches to reduce delivery costs. However, sending several jobs in batches can have a negative effect on other scheduling-related objective functions such as minimizing the number of tardy jobs which is often used to rate managers’ performance in many manufacturing environments. This paper aims to minimize the number of weighted tardy jobs and the sum of delivery costs of a two-stage assembly flow-shop problem in a batch delivery system. We present a mixed-integer linear programming (MILP) model to solve the problem. As this is an MILP model, the commercial solver (the CPLEX solver) is not guaranteed to find the optimal solution for large-size problems at a reasonable amount of time. We present several numerical examples to confirm the accuracy of the model.

Keywords: scheduling, two-stage assembly flow-shop, tardy jobs, batched delivery system

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634 A Hybrid Pareto-Based Swarm Optimization Algorithm for the Multi-Objective Flexible Job Shop Scheduling Problems

Authors: Aydin Teymourifar, Gurkan Ozturk

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In this paper, a new hybrid particle swarm optimization algorithm is proposed for the multi-objective flexible job shop scheduling problem that is very important and hard combinatorial problem. The Pareto approach is used for solving the multi-objective problem. Several new local search heuristics are integrated into an algorithm based on the critical block concept to enhance the performance of the algorithm. The algorithm is compared with the recently published multi-objective algorithms based on benchmarks selected from the literature. Several metrics are used for quantifying performance and comparison of the achieved solutions. The algorithms are also compared based on the Weighting summation of objectives approach. The proposed algorithm can find the Pareto solutions more efficiently than the compared algorithms in less computational time.

Keywords: swarm-based optimization, local search, Pareto optimality, flexible job shop scheduling, multi-objective optimization

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633 Non-Population Search Algorithms for Capacitated Material Requirement Planning in Multi-Stage Assembly Flow Shop with Alternative Machines

Authors: Watcharapan Sukkerd, Teeradej Wuttipornpun

Abstract:

This paper aims to present non-population search algorithms called tabu search (TS), simulated annealing (SA) and variable neighborhood search (VNS) to minimize the total cost of capacitated MRP problem in multi-stage assembly flow shop with two alternative machines. There are three main steps for the algorithm. Firstly, an initial sequence of orders is constructed by a simple due date-based dispatching rule. Secondly, the sequence of orders is repeatedly improved to reduce the total cost by applying TS, SA and VNS separately. Finally, the total cost is further reduced by optimizing the start time of each operation using the linear programming (LP) model. Parameters of the algorithm are tuned by using real data from automotive companies. The result shows that VNS significantly outperforms TS, SA and the existing algorithm.

Keywords: capacitated MRP, tabu search, simulated annealing, variable neighborhood search, linear programming, assembly flow shop, application in industry

Procedia PDF Downloads 207
632 A Coordination of Supply Chain Disruption in Different Types of Manufacturing Environments: A Case Study of Sugar Manufacturing Company

Authors: Max Moleke, Gilbert Mbonde

Abstract:

Coordinating supply chain process within a manufacturing environment is a very critical aspect of any organization. Nowadays, most manufacturing industries turn to look at only the financial indicator which in real life situation on the shop floor, there are a number of supply chain disruptions that are been ignored. In this work, we had to look at different types of supply chain disruption and their various impact within the organization. A number of Industrial engineering tools are employed which includes, Multifactor productivity, activity on arrow and rescheduling plans. The final result shows that supply chain disruption various with different geographical area where the production plant is operating.

Keywords: supply chain, disruptions, flow shop scheduling, uncertainty

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631 A Study on the Impact of Perceived Benefits and Switching Costs of Consumers When Shifting from Brick and Mortar Store to Online Shopping of Apparels

Authors: Havisha Banda

Abstract:

Recent advancements in technology have facilitated commerce around the globe. The online medium of commerce has provided and will continue to provide great opportunities for consumers and businesses. Advancements in technology enable apparel stores, for instance, to improve their online services by using personalized virtual models allowing consumers to visualize the product on the model to determine correct sizing and fit. In addition to many advantages in online shopping the consumers will also have to undergo many types of switching costs in this process of buying apparel online. This study is to identify such switching costs and switching benefits from traditional shopping to online shopping and to understand what the consumers value the most. The scope of this study is to understand the types of switching costs and the factors that actually allow the consumers to shift from brick and mortar to online shopping and also to understand why a certain set of customers consider to purchase offline. Hence this study helps to understand the perceived cost and perceived benefit relation that the consumer draws in purchasing the garments online. This will help the upcoming e-commerce sites and brick and mortar store to understand the various factors and formulate new policies and implement strategies in their own ways to attract the customers and to retain them. A sample of 35 is considered for the process of laddered interviews. In the era of e-commerce there are people who feel comfortable to shop in a retail store rather than online purchase. Few respondents who shop online do not prefer to shop apparel online. Few respondents said that they shop online only for apparels. Most of the variables match in terms of switching costs and also in regard to benefits.

Keywords: e-commerce, switching costs, switching benefits, apparel shopping

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630 From Shop-Floor to Classroom and from Classroom to Shop-Floor: A Way to Bridge Gap between Industry and Academy

Authors: Muhammad Haris Aziz, Shoaib Sarfraz, Chanchal Saha

Abstract:

The basic functions of a university are research and education. Research develops theories and education provides the link between the theory and the practical. Being an applied science, the link between theory and practice needs to be strong in engineering disciplines. But there remains a gap between industry and academy due lack of understanding and awareness from both sides. This gap is been shorten with an industrial engineering graduate class composed of a mix of students from industrial background and from theoretical background. Results are four industrial case studies which are the outcome of group projects in a course on operations research.

Keywords: industrial-academia linkage, operations research, industrial engineering, engineering education.

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629 An Advanced Match-Up Scheduling Under Single Machine Breakdown

Authors: J. Ikome, M. Ndeley

Abstract:

When a machine breakdown forces a Modified Flow Shop (MFS) out of the prescribed state, the proposed strategy reschedules part of the initial schedule to match up with the preschedule at some point. The objective is to create a new schedule that is consistent with the other production planning decisions like material flow, tooling and purchasing by utilizing the time critical decision making concept. We propose a new rescheduling strategy and a match-up point determination procedure through a feedback mechanism to increase both the schedule quality and stability. The proposed approach is compared with alternative reactive scheduling methods under different experimental settings.

Keywords: advanced critical task methods modified flow shop (MFS), Manufacturing, experiment, determination

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628 Towards a Standardization in Scheduling Models: Assessing the Variety of Homonyms

Authors: Marcel Rojahn, Edzard Weber, Norbert Gronau

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Terminology is a critical instrument for each researcher. Different terminologies for the same research object may arise in different research communities. By this inconsistency, many synergistic effects get lost. Theories and models will be more understandable and reusable if a common terminology is applied. This paper examines the terminological (in) consistency for the research field of job-shop scheduling through a literature review. There is an enormous variety in the choice of terms and mathematical notation for the same concept. The comparability, reusability, and combinability of scheduling methods are unnecessarily hampered by the arbitrary use of homonyms and synonyms. The acceptance in the community of used variables and notation forms is shown by means of a compliance quotient. This is proven by the evaluation of 240 scientific publications on planning methods.

Keywords: job-shop scheduling, terminology, notation, standardization

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627 Determining the Distance Consumers Are Willing to Travel to a Store: A Structural Equation Model Approach

Authors: Fuseina Mahama, Lieselot Vanhaverbeke

Abstract:

This research investigates the impact of patronage determinants on the distance consumers are willing to travel to patronize a tire shop. Although store patronage has been acknowledged as an important domain and has received substantial research interest, most of the studies so far conducted focus on grocery retail, leaving other categories of goods widely unexplored. In this study, we focus on car tires and provide a new perspective to the specific factors that influence tire shop patronage. An online survey of consumers’ tyre purchasing behaviour was conducted among private car owners in Belgium. A sample of 864 respondents was used in the study, with almost four out of five of them being male. 84% of the respondents had purchased a car tyre in the last 24 months and on average travelled 22.4kms to patronise a tyre shop. We tested the direct and mediated effects of store choice determinants on distance consumers are willing to travel. All hypotheses were tested using Structural Equation Modelling (SEM). Our findings show that with an increase in the consumer’s age the distance they were willing to travel to a tire shop decreased. Similarly, consumers who deemed proximity an important determinant of a tire shop our findings confirmed a negative effect on willingness to travel. On the other hand, the determinants price, personal contact and professionalism all had a positive effect on distance. This means that consumers actively sought out tire shops with these characteristics and were willing to travel longer distances in order to visit them. The indirect effects of the determinants flexible opening hours, family recommendation, dealer reputation, receiving auto service at home and availability of preferred brand on distance are mediated by dealer trust. Gender had a minimal effect on distance, with females exhibiting a stronger relation in terms of dealer trust as compared to males. Overall, we found that market relevant factors were better predictors of distance; and proximity, dealer trust and professionalism have the most profound effects on distance that consumers are willing to travel. This is related to the fact that the nature of shopping goods (among which are car tires) typically reinforces consumers to be more engaged in the shopping process, therefore factors that have to do with the store (e.g. location) and shopping process play a key role in store choice decision. These findings are very specific to shopping goods and cannot be generalized to other categories of goods. For marketers and retailers these findings can have direct implications on their location strategies. The factors found to be relevant to tire shop patronage will be used in our next study to calibrate a location model to be utilised to identify the optimum location for siting new tyre shop outlets and service centres.

Keywords: dealer trust, distance to store, tire store patronage, willingness to travel

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626 The Effect of Improvement Programs in the Mean Time to Repair and in the Mean Time between Failures on Overall Lead Time: A Simulation Using the System Dynamics-Factory Physics Model

Authors: Marcel Heimar Ribeiro Utiyama, Fernanda Caveiro Correia, Dario Henrique Alliprandini

Abstract:

The importance of the correct allocation of improvement programs is of growing interest in recent years. Due to their limited resources, companies must ensure that their financial resources are directed to the correct workstations in order to be the most effective and survive facing the strong competition. However, to our best knowledge, the literature about allocation of improvement programs does not analyze in depth this problem when the flow shop process has two capacity constrained resources. This is a research gap which is deeply studied in this work. The purpose of this work is to identify the best strategy to allocate improvement programs in a flow shop with two capacity constrained resources. Data were collected from a flow shop process with seven workstations in an industrial control and automation company, which process 13.690 units on average per month. The data were used to conduct a simulation with the System Dynamics-Factory Physics model. The main variables considered, due to their importance on lead time reduction, were the mean time between failures and the mean time to repair. The lead time reduction was the output measure of the simulations. Ten different strategies were created: (i) focused time to repair improvement, (ii) focused time between failures improvement, (iii) distributed time to repair improvement, (iv) distributed time between failures improvement, (v) focused time to repair and time between failures improvement, (vi) distributed time to repair and between failures improvement, (vii) hybrid time to repair improvement, (viii) hybrid time between failures improvements, (ix) time to repair improvement strategy towards the two capacity constrained resources, (x) time between failures improvement strategy towards the two capacity constrained resources. The ten strategies tested are variations of the three main strategies for improvement programs named focused, distributed and hybrid. Several comparisons among the effect of the ten strategies in lead time reduction were performed. The results indicated that for the flow shop analyzed, the focused strategies delivered the best results. When it is not possible to perform a large investment on the capacity constrained resources, companies should use hybrid approaches. An important contribution to the academy is the hybrid approach, which proposes a new way to direct the efforts of improvements. In addition, the study in a flow shop with two strong capacity constrained resources (more than 95% of utilization) is an important contribution to the literature. Another important contribution is the problem of allocation with two CCRs and the possibility of having floating capacity constrained resources. The results provided the best improvement strategies considering the different strategies of allocation of improvement programs and different positions of the capacity constrained resources. Finally, it is possible to state that both strategies, hybrid time to repair improvement and hybrid time between failures improvement, delivered best results compared to the respective distributed strategies. The main limitations of this study are mainly regarding the flow shop analyzed. Future work can further investigate different flow shop configurations like a varying number of workstations, different number of products or even different positions of the two capacity constrained resources.

Keywords: allocation of improvement programs, capacity constrained resource, hybrid strategy, lead time, mean time to repair, mean time between failures

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625 Novel Uses of Discarded Work Rolls of Cold Rolling Mills in Hot Strip Mill of Tata Steel India

Authors: Uday Shanker Goel, Vinay Vasant Mahashabde, Biswajit Ghosh, Arvind Jha, Amit Kumar, Sanjay Kumar Patel, Uma Shanker Pattanaik, Vinit Kumar Shah, Chaitanya Bhanu

Abstract:

Pinch rolls of the Hot Mills must possess resistance to wear, thermal stability, high thermal conductivity and through hardness. Conventionally, pinch rolls have been procured either as new ones or refurbished ones. Discarded Work Rolls from the Cold Mill were taken and machined inhouse at Tata Steel to be used subsequently as the bottom pinch rolls of the Hot Mill. The hardness of the scrapped work rolls from CRM is close to 55HRC and the typical composition is ( C - 0.8% , Mn - 0.40 % , Si - 0.40% , Cr - 3.5% , Mo - 0.5% & V - 0.1% ).The Innovation was the use of a roll which would otherwise have been otherwise discarded as scrap. Also, the innovation helped in using the scrapped roll which had better wear and heat resistance. In a conventional Pinch roil (Hardness 50 HRC and typical chemistry - C - 10% , Mo+Co+V+Nb ~ 5 % ) , Pick-up is a condition whereby foreign material becomes adhered to the surface of the pinch roll during service. The foreign material is usually adhered metal from the actual product being rolled. The main attributes of the weld overlay rolls are wear resistance and crack resistance. However, the weld overlay roll has a strong tendency for strip pick-up particularly in the area of bead overlap. However, the greatest disadvantage is the depth of weld deposit, which is less than half of the usable shell thickness in most mills. Because of this, the stainless rolls require re-welding on a routine basis. By providing a significantly cheaper in house and more robust alternative of the existing bottom pinch rolls , this innovation results in significant lower worries for the roll shop. Pinch rolls now don't have to be sent outside Jamshedpur for refurbishment or for procuring new ones. Scrapped rolls from adjacent Cold Mill are procured and sent for machining to our Machine Shop inside Tata Steel works in Jamshedpur. This is far more convenient than the older methodology. The idea is also being deployed to the other hot mills of Tata Steel. Multiple campaigns have been tried out at both down coilers of Hot Strip with significantly lower wear.

Keywords: hot rolling flat, cold mill work roll, hot strip pinch roll, strip surface

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624 Jordan Curves in the Digital Plane with Respect to the Connectednesses given by Certain Adjacency Graphs

Authors: Josef Slapal

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Digital images are approximations of real ones and, therefore, to be able to study them, we need the digital plane Z2 to be equipped with a convenient structure that behaves analogously to the Euclidean topology on the real plane. In particular, it is required that such a structure allows for a digital analogue of the Jordan curve theorem. We introduce certain adjacency graphs on the digital plane and prove digital Jordan curves for them thus showing that the graphs provide convenient structures on Z2 for the study and processing of digital images. Further convenient structures including the wellknown Khalimsky and Marcus-Wyse adjacency graphs may be obtained as quotients of the graphs introduced. Since digital Jordan curves represent borders of objects in digital images, the adjacency graphs discussed may be used as background structures on the digital plane for solving the problems of digital image processing that are closely related to borders like border detection, contour filling, pattern recognition, thinning, etc.

Keywords: digital plane, adjacency graph, Jordan curve, quotient adjacency

Procedia PDF Downloads 334
623 Heat: A Healthy Eating Programme

Authors: Osagbai Joshua Eriki, Ngozi Agunwamba, Alice Hill, Lorna Almond, Maniya Duffy, Devashini Naidoo, David Ho, Raman Deo

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Aims: To evaluate the baseline eating pattern in a psychiatric hospital through quantifying purchases of food and drink items at the hospital shop and to implement a traffic light healthy eating labeling system. Method: A electronic till with reporting capabilities was purchased. A two-week period of baseline data collection was conducted. Thereafter, a system for labeling items based on the nutritional value of the food items at the hospital shop was implemented. Green labeling represented the items with the lowest calories and red the most. Further data was collated on the number and types of items purchased by patients according to the category, and the initial effectiveness of the system was evaluated. Result: Despite the implementation of the traffic light system, the red category had the highest number of items purchased by patients, highlighting the importance of promoting healthy eating choices. However, the study also showed that the system was effective in promoting healthy options, as the number of items purchased from the green category increased during the study period. Conclusion: The implementation of a traffic light labeling system for items sold at the hospital shop offers a promising approach to promoting healthy eating habits and choices. This is likely to contribute to a toolkit of measures when considering the multifactorial challenges that obesity and weight issues pose for long-stay psychiatric inpatients

Keywords: mental health, nutrition, food, healthy

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622 Agile Implementation of 'PULL' Principles in a Manufacturing Process Chain for Aerospace Composite Parts

Authors: Torsten Mielitz, Dietmar Schulz, York C. Roth

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Market forecasts show a significant increase in the demand for aircraft within the next two decades and production rates will be adapted accordingly. Improvements and optimizations in the industrial system are becoming more important to cope with future challenges in manufacturing and assembly. Highest quality standards have to be met for aerospace parts, whereas cost effective production in industrial systems and methodologies are also a key driver. A look at other industries like e.g., automotive shows well established processes to streamline existing manufacturing systems. In this paper, the implementation of 'PULL' principles in an existing manufacturing process chain for a large scale composite part is presented. A nonlinear extrapolation based on 'Little's Law' showed a risk of a significant increase of parts needed in the process chain to meet future demand. A project has been set up to mitigate the risk whereas the methodology has been changed from a traditional milestone approach in the beginning towards an agile way of working in the end in order to facilitate immediate benefits in the shop-floor. Finally, delivery rates could be increased avoiding more semi-finished parts in the process chain (work in progress & inventory) by the successful implementation of the 'PULL' philosophy in the shop-floor between the work stations. Lessons learned during the running project as well as implementation and operations phases are discussed in order to share best practices.

Keywords: aerospace composite part manufacturing, PULL principles, shop-floor implementation, lessons learned

Procedia PDF Downloads 143
621 A Genetic Algorithm Based Permutation and Non-Permutation Scheduling Heuristics for Finite Capacity Material Requirement Planning Problem

Authors: Watchara Songserm, Teeradej Wuttipornpun

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This paper presents a genetic algorithm based permutation and non-permutation scheduling heuristics (GAPNP) to solve a multi-stage finite capacity material requirement planning (FCMRP) problem in automotive assembly flow shop with unrelated parallel machines. In the algorithm, the sequences of orders are iteratively improved by the GA characteristics, whereas the required operations are scheduled based on the presented permutation and non-permutation heuristics. Finally, a linear programming is applied to minimize the total cost. The presented GAPNP algorithm is evaluated by using real datasets from automotive companies. The required parameters for GAPNP are intently tuned to obtain a common parameter setting for all case studies. The results show that GAPNP significantly outperforms the benchmark algorithm about 30% on average.

Keywords: capacitated MRP, genetic algorithm, linear programming, automotive industries, flow shop, application in industry

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620 The Relationship of Service Marketing Mix and Intention to Repurchase of Thai Dessert

Authors: Siri-Orn Champatong

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This research aimed to study the relationship between attitudes toward marketing mix and customers’ repurchase intention of Thai dessert in case of Ekachai Salee Suphan’s shop in Thailand. This study employed by survey and quantitative research and the questionnaire was used to collect the data from 385 sampled of customers who visited at Ekachai Salee Suphan's shop in Thailand. The descriptive statistics and Pearson’s correlation coefficient analysis was used to analyze data. The research found that the customers’ perception on the overall and individual aspects of attitudes toward marketing mix include products, prices, promotions, and physical characteristics were at very good level, but distribution channels, staffs, and management process were at good level. Furthermore, the hypothesis tests found that attitudes toward overall marketing mix had relationship with individual aspects of intention that were the repurchase intention, willingness to recommend others to repurchase, and possibility to repurchase with statistical significance level of 0.01.

Keywords: intention, repurchase, service marketing mix, Thai dessert

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619 Collapsed World Heritage Site: Supply Chain Effect: Case Study of Monument in Kathmandu Valley after the Devastating Earthquake in Nepal

Authors: Rajaram Mahat, Roshan Khadka

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Nepal has remained a land of diverse people and culture consisting more than hundred ethnic and caste groups with 92 different languages. Each ethnic and cast group have their own common culture. Kathmandu, the capital city of Nepal is one of the multi-ethnic, lingual and cultural ancient places. Dozens of monuments with the history of more than thousand years are located in Kathmandu Valley. More or less all of the heritage site have been affected by devastating earthquake in April and May 2015. This study shows the most popular tourist and pilgrim’s destination like Kathmandu Darbar Square, Bhaktapur Darbarsquare, Patan Darbar Square, Swayambhunath temple complex, Dharahara Tower, Pasupatinath Hindu Religious Complex etc. have been massively destroyed. This paper analyses the socio economic consequence to the community people of world heritage site after devastating earthquake in Kathmandu Valley. Initial findings indicate that domestic and international current tourists flow have decreased by 41% and average 23% of local craft shop, curio shop, hotel, restaurant, grocery store, footpath shop including employment of tourist guide have been closed down as well as travel & tour business has decreased by 12%. Supply chain effect is noticeably shown in particular collapsed world heritage sites. It has also seen negative impact to National economy as well. This study has recommended to government of Nepal and other donor to reconstruct the collapse world heritage sites and to preserve the other existing world heritage site with treatment of earthquake resist structure as soon as possible.

Keywords: world heritage, community, earthquake, supply chain effect

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618 A General Variable Neighborhood Search Algorithm to Minimize Makespan of the Distributed Permutation Flowshop Scheduling Problem

Authors: G. M. Komaki, S. Mobin, E. Teymourian, S. Sheikh

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This paper addresses minimizing the makespan of the distributed permutation flow shop scheduling problem. In this problem, there are several parallel identical factories or flowshops each with series of similar machines. Each job should be allocated to one of the factories and all of the operations of the jobs should be performed in the allocated factory. This problem has recently gained attention and due to NP-Hard nature of the problem, metaheuristic algorithms have been proposed to tackle it. Majority of the proposed algorithms require large computational time which is the main drawback. In this study, a general variable neighborhood search algorithm (GVNS) is proposed where several time-saving schemes have been incorporated into it. Also, the GVNS uses the sophisticated method to change the shaking procedure or perturbation depending on the progress of the incumbent solution to prevent stagnation of the search. The performance of the proposed algorithm is compared to the state-of-the-art algorithms based on standard benchmark instances.

Keywords: distributed permutation flow shop, scheduling, makespan, general variable neighborhood search algorithm

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617 Decomposition of the Customer-Server Interaction in Grocery Shops

Authors: Andreas Ahrens, Ojaras Purvinis, Jelena Zascerinska

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A successful shopping experience without overcrowded shops and long waiting times undoubtedly leads to the release of happiness hormones and is generally considered the goal of any optimization. Factors influencing the shopping experience can be divided into internal and external ones. External factors are related, e. g. to the arrival of the customers to the shop, whereas internal are linked with the service process itself when checking out (waiting in the queue to the cash register and the scanning of the goods as well as the payment process itself) or any other non-expected delay when changing the status from a visitor to a buyer by choosing goods or items. This paper divides the customer-server interaction into five phases starting with the customer's arrival at the shop, the selection of goods, the buyer waiting in the queue to the cash register, the payment process, and ending with the customer or buyer's departure. Our simulation results show how five phases are intertwined and influence the overall shopping experience. Parameters for measuring the shopping experience are estimated based on the burstiness level in each of the five phases of the customer-server interaction.

Keywords: customers’ burstiness, cash register, customers’ wait-ing time, gap distribution function

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616 An Efficient Hybrid Approach Based on Multi-Agent System and Emergence Method for the Integration of Systematic Preventive Maintenance Policies

Authors: Abdelhadi Adel, Kadri Ouahab

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This paper proposes a hybrid algorithm for the integration of systematic preventive maintenance policies in hybrid flow shop scheduling to minimize makespan. We have implemented a problem-solving approach for optimizing the processing time, methods based on metaheuristics. The proposed approach is inspired by the behavior of the human body. This hybridization is between a multi-agent system and inspirations of the human body, especially genetics. The effectiveness of our approach has been demonstrated repeatedly in this paper. To solve such a complex problem, we proposed an approach which we have used advanced operators such as uniform crossover set and single point mutation. The proposed approach is applied to three preventive maintenance policies. These policies are intended to maximize the availability or to maintain a minimum level of reliability during the production chain. The results show that our algorithm outperforms existing algorithms. We assumed that the machines might be unavailable periodically during the production scheduling.

Keywords: multi-agent systems, emergence, genetic algorithm, makespan, systematic maintenance, scheduling, hybrid flow shop scheduling

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615 Biosensor Technologies in Neurotransmitters Detection

Authors: Joanna Cabaj, Sylwia Baluta, Karol Malecha

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Catecholamines are vital neurotransmitters that mediate a variety of central nervous system functions, such as motor control, cognition, emotion, memory processing, and endocrine modulation. Dysfunctions in catecholamine neurotransmission are induced in some neurologic and neuropsychiatric diseases. Changeable neurotransmitters level in biological fluids can be a marker of several neurological disorders. Because of its significance in analytical techniques and diagnostics, sensitive and selective detection of neurotransmitters is increasingly attracting a lot of attention in different areas of bio-analysis or biomedical research. Recently, optical techniques for the detection of catecholamines have attracted interests due to their reasonable cost, convenient control, as well as maneuverability in biological environments. Nevertheless, with the observed need for a sensitive and selective catecholamines sensor, the development of a convenient method for this neurotransmitter is still at its basic level. The manipulation of nanostructured materials in conjunction with biological molecules has led to the development of a new class of hybrid-modified enzymatic sensors in which both enhancement of charge transport and biological activity preservation may be obtained. Immobilization of biomaterials on electrode surfaces is the crucial step in fabricating electrochemical as well as optical biosensors and bioelectronic devices. Continuing systematic investigation in manufacturing of enzyme–conducting sensitive systems, here is presented a convenient fluorescence as well as electrochemical sensing strategy for catecholamines detection.

Keywords: biosensors, catecholamines, fluorescence, enzymes

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614 Facilitating Factors for the Success of Mobile Service Providers in Bangkok Metropolitan

Authors: Yananda Siraphatthada

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The objectives of this research were to study the level of influencing factors, leadership, supply chain management, innovation, competitive advantages, business success, and affecting factors to the business success of the mobile phone system service providers in Bangkok Metropolitan. This research was done by the quantitative approach and the qualitative approach. The quantitative approach was used for questionnaires to collect data from the 331 mobile service shop managers franchised by AIS, Dtac and TrueMove. The mobile phone system service providers/shop managers were randomly stratified and proportionally allocated into subgroups exclusive to the number of the providers in each network. In terms of qualitative method, there were in-depth interviews of 6 mobile service providers/managers of Telewiz and Dtac and TrueMove shop to find the agreement or disagreement with the content analysis method. Descriptive Statistics, including Frequency, Percentage, Means and Standard Deviation were employed; also, the Structural Equation Model (SEM) was used as a tool for data analysis. The content analysis method was applied to identify key patterns emerging from the interview responses. The two data sets were brought together for comparing and contrasting to make the findings, providing triangulation to enrich result interpretation. It revealed that the level of the influencing factors – leadership, innovation management, supply chain management, and business competitiveness had an impact at a great level, but that the level of factors, innovation and the business, financial success and nonbusiness financial success of the mobile phone system service providers in Bangkok Metropolitan, is at the highest level. Moreover, the business influencing factors, competitive advantages in the business of mobile system service providers which were leadership, supply chain management, innovation management, business advantages, and business success, had statistical significance at .01 which corresponded to the data from the interviews.

Keywords: mobile service providers, facilitating factors, Bangkok Metropolitan, business success

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613 Coping Strategies of Parents of a Child with Asthma in Relation to the Child's Disease

Authors: Irma Nool, Katriin Saueauk, Ebe Siimson, Vlada Žukova, Elise Gertrud Vellet

Abstract:

Background: Asthma is one of themostcommonchronicdiseases in children, whichcansignificantlyaffectchildren, and challengetheirfamilies. The unpredictability, frequency, and control of asthma attacks have a profound effect on the daily lives of familieswithasthmaticchildren. Thereis a growing body of researchshowingthatthequality of life of parents and childrenislinkedtothedevelopment of asthma. Theoretical and clinicalstudiesprovethat a positive and well-functioningfamilysystemhelpstocopebetterwiththediagnosis of the chronic disease. The aim of theresearchwastodescribethecopingstrategies of parents of a childwithasthmaconcerningthechild'sillness. Method: Theresearchwasanempirical, quantitative, descriptive study. Thesamplewastheparents of a child with asthma at the Tallinn Children'sHospital, whose child was in inpatienttreatmentbetween 07.04.2021 and 12.09.2021. This is a convenient sample. 59 parentsrepliedtothequestionnaire. The questionnaire “CopingInventoryforStressfulSituations” wasusedtocollectthedata, whichwastranslatedinto Estonian and Russian using a back-and-forthtranslationtechnique. Thequestionnairewasanswered on a 5-point Likert scale. Dataanalysiswasperformedusing SPSS 26.0, descriptive statistics, with mean values and standard deviation. The Mann-Whitney U test wasusedtocomparefathers and motherscopingstrategies. PermissiontoconductresearchhasbeenobtainedfromtheEthicsCommitteeforHuman Research of theInstituteforHealthDevelopment. Results: The mean age of the respondents was 40 ± 6.2 years (median 40), withtheyoungestbeing 27 yearsold and the oldest being 57 yearsold. Of the respondents, 51 (86.4%) were mothers, and 8 (13.6%) werefathers. Parentsusedthemosttask-orientedcopingstrategies (mean 3.35 ± 0.602) and theleastemotion-orientedcopingstrategies (mean 1.97 ± 0.526). Mothersusedmoretask-orientedcopingstrategies (p = 0.001) than fathers. Fathersusedemotion-orientedcopingstrategiesless (p = 0.024) than mothers. mothersplantheirtimebetter (p = 0.043), focus on the problem and look at how to solve it (p = 0.007), and makeanefforttogetthingsdone (p = 0.045). mothersblamethemselvesmorefornotknowingwhattodo (p = 0.045) and worryaboutwhattheyshoulddo (p = 0.027). mothers look more at the goods displayed in the shop windows (p = 0.018) and go for a walk (p = 0.007) compared to fathers. Conclusions: The results of theresearchshowedthatproblem-orientedcopingstrategiesare used the most and there are differences in the behavior of fathers and mothers. Thisshouldbetakenintoaccountwhenprovidingfamily-centered nursing care.

Keywords: asthma, coping strategies, parents, family

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612 Religious Discrimination Against Small Business Owners: Evidence from the 1875 Cadastral Survey of Istanbul

Authors: Burak Unveren, Ecem Uygun, Özdemi̇r Teke

Abstract:

A large body of literature documents how the Ottoman Empire's economic decline in relation to Western Europe was exacerbated by the unequal legal treatment of its subjects based on creed. Motivated by this debate, we empirically explore whether property taxes collected from businesses in Istanbul discriminated against or favored non-Muslims after the cadastral survey of the capital in 1875. The survey was conducted to determine the property taxes. And the process was potentially susceptible to the biased views of the surveyors who calculated the taxes payable via their subjective appraisals of all real properties. According to our results, in contrast to widely held beliefs regarding 19th-century Istanbul, the number of Muslim shop owners is higher than that of non-Muslims. Moreover, we find evidence for taxes collected from non-Muslim shop and store owners to be higher compared to Muslims, even after controlling for all physical features (e.g., size, location, etc.). These results directly pertain to the fiscal capacity of the Ottoman state and its economic divergence from Europe in the 19th century. Surprisingly, the data also indicates no statistically different tax differentials between male and female property owners.

Keywords: economic history, taxation, small business, discrimination

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611 Family Planning and HIV Integration: A One-stop Shop Model at Spilhaus Clinic, Harare Zimbabwe

Authors: Mercy Marimirofa, Farai Machinga, Alfred Zvoushe, Tsitsidzaishe Musvosvi

Abstract:

The Government of Zimbabwe embarked on integrating family planning with Sexually Transmitted Infection (STI) and Human Immunodeficiency Virus (HIV) services in May 2020 with support from the World Health Organization (WHO). There was high HIV prevalence, incidence rates and STI infections among women attending FP clinics. Spilhaus is a specialized center of excellence clinic which offers a range of sexual reproductive health services. HIV services were limited to testing only, and clients were referred to other facilities for further management. Integration of services requires that all the services be available at one point so that clients will access them during their visit to the facility. Objectives: The study was conducted to assess the impact the one-stop-shop model has made in accessing integrated Family Planning services and sexual reproductive health services compared to the supermarket approach. It also assessed the relationship family planning services have with other sexual reproductive health services. Methods: A secondary data analysis was conducted at Spilhaus clinic in Harare using family planning registers and HIV services registers comparing years 2019 and 2021. A 2 sample t-test was used to determine the difference in clients accessing the services under the two models. A Spearman’s rank correlation was used to determine if accessing family planning services has a relationship with other sexual reproductive health services. Results: In 2019, 7,548 clients visited the Spilhaus clinic compared to 8,265 during the period January to December 2021. The median age for all clients accessing services was 32 years. An increase of 69% in the number of services accessed was recorded from 2019 to 2021. More services were accessed in 2021. There was no difference in the number of clients accessing family planning services cervical cancer, and HIV services. A difference was found in the number of clients who were offered STI screening services. There was also a relationship between accessing family planning services and STI screening services (ρ = 0.729, p-value=0.006). Conclusion: Programming towards SRH services was a great achievement, the use of an integrated approach proved to be cost-effective as it minimised the required resources for separate programs. Clients accessed important health needs at once. The integration of these services provided an opportunity to offer comprehensive information which addressed an individual’s sexual reproductive health needs.

Keywords: intergration, one stop shop, family planning, reproductive health

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610 Developing Alternative Recovery Technology of Waste Heat in Automobile Factory

Authors: Kun-Ping Cheng, Dong-Shang Chang, Rou-Wen Wang

Abstract:

Pre-treatment of automobile paint-shop procedures are the preparation of warm water rinsing tank, hot water rinsing tank, degreasing tank, phosphate tank. The conventional boiler steam fuel is natural gas, producing steam to supply the heat exchange of each tank sink. In this study, the high-frequency soldering economizer is developed for recovering waste heat in the automotive paint-shop (RTO, Regenerative Thermal Oxidation). The heat recovery rate of the new economizer is 20% to 30% higher than the conventional embedded heat pipe. The adaptive control system responded to both RTO furnace exhaust gas and heat demands. In order to maintain the temperature range of the tanks, pre-treatment tanks are directly heated by waste heat recovery device (gas-to-water heat exchanger) through the hot water cycle of heat transfer. The performance of developed waste heat recovery system shows the annual recovery achieved to 1,226,411,483 Kcal of heat (137.8 thousand cubic meters of natural gas). Boiler can reduce fuel consumption by 20 to 30 percent compared to without waste heat recovery. In order to alleviate environmental impacts, the temperature at the end of the flue is further reduced from 160 to 110°C. The innovative waste heat recovery is helpful to energy savings and sustainable environment.

Keywords: waste heat recovery system, sustainability, RTO (Regenerative Thermal Oxidation), economizer, automotive industry

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609 Optimization of Hot Metal Charging Circuit in a Steel Melting Shop Using Industrial Engineering Techniques for Achieving Manufacturing Excellence

Authors: N. Singh, A. Khullar, R. Shrivastava, I. Singh, A. S. Kumar

Abstract:

Steel forms the basis of any modern society and is essential to economic growth. India’s annual crude steel production has seen a consistent increase over the past years and is poised to grow to 300 million tons per annum by 2030-31 from current level of 110-120 million tons per annum. Steel industry is highly capital-intensive industry and to remain competitive, it is imperative that it invests in operational excellence. Due to inherent nature of the industry, there is large amount of variability in its supply chain both internally and externally. Production and productivity of a steel plant is greatly affected by the bottlenecks present in material flow logistics. The internal logistics constituting of transport of liquid metal within a steel melting shop (SMS) presents an opportunity in increasing the throughput with marginal capital investment. The study was carried out at one of the SMS of an integrated steel plant located in the eastern part of India. The plant has three SMS’s and the study was carried out at one of them. The objective of this study was to identify means to optimize SMS hot metal logistics through application of industrial engineering techniques. The study also covered the identification of non-value-added activities and proposed methods to eliminate the delays and improve the throughput of the SMS.

Keywords: optimization, steel making, supply chain, throughput enhancement, workforce productivity

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608 Factory Communication System for Customer-Based Production Execution: An Empirical Study on the Manufacturing System Entropy

Authors: Nyashadzashe Chiraga, Anthony Walker, Glen Bright

Abstract:

The manufacturing industry is currently experiencing a paradigm shift into the Fourth Industrial Revolution in which customers are increasingly at the epicentre of production. The high degree of production customization and personalization requires a flexible manufacturing system that will rapidly respond to the dynamic and volatile changes driven by the market. They are a gap in technology that allows for the optimal flow of information and optimal manufacturing operations on the shop floor regardless of the rapid changes in the fixture and part demands. Information is the reduction of uncertainty; it gives meaning and context on the state of each cell. The amount of information needed to describe cellular manufacturing systems is investigated by two measures: the structural entropy and the operational entropy. Structural entropy is the expected amount of information needed to describe scheduled states of a manufacturing system. While operational entropy is the amount of information that describes the scheduled states of a manufacturing system, which occur during the actual manufacturing operation. Using Anylogic simulator a typical manufacturing job shop was set-up with a cellular manufacturing configuration. The cellular make-up of the configuration included; a Material handling cell, 3D Printer cell, Assembly cell, manufacturing cell and Quality control cell. The factory shop provides manufactured parts to a number of clients, and there are substantial variations in the part configurations, new part designs are continually being introduced to the system. Based on the normal expected production schedule, the schedule adherence was calculated from the structural entropy and operation entropy of varying the amounts of information communicated in simulated runs. The structural entropy denotes a system that is in control; the necessary real-time information is readily available to the decision maker at any point in time. For contractive analysis, different out of control scenarios were run, in which changes in the manufacturing environment were not effectively communicated resulting in deviations in the original predetermined schedule. The operational entropy was calculated from the actual operations. From the results obtained in the empirical study, it was seen that increasing, the efficiency of a factory communication system increases the degree of adherence of a job to the expected schedule. The performance of downstream production flow fed from the parallel upstream flow of information on the factory state was increased.

Keywords: information entropy, communication in manufacturing, mass customisation, scheduling

Procedia PDF Downloads 218