Operation Research

Garment manufacturers constantly seek methods to improve efficiency and productivity. Thus, the study was undertaken to identify non-productive time (NPT) and analyze the root causes. The effect of NPT on productivity standard minute value, labor efficiency, and targets was also analyzed in an apparel manufacturing unit of Bangladesh. The study discusses various approaches to reduce NPT. These include applying time study why-why-bacause of logic (WWBLA), fishbone techniques to minimize the NPT of cutting and sewing process, and detecting the reason for NPT through root cause analysis and the process through which it can be reduced. The effectiveness of these strategies demonstrates efficiency gains and positive impacts on productivity. The productivity improved 6-10% after taking countermeasures against the NPT. The study highlights the importance of precise time measurements and workflow analysis in identifying and eliminating NPT. By implementing these methods, garment manufacturers can achieve operational excellence, minimize process waste, and enhance competitiveness.

Nowadays, business manufacturers must have the ability to respond rapidly to customer demands. In order to have this power, the organization generally produces mass volumes of specific products. In mass production systems of specified products, assembly lines are generally used. In assembly production, imbalances are wellknown problems. Line balancing (LB) is the leveling of the workload across all processes in a line or value stream to remove bottlenecks and excess capacity. Poor balance causes an increase in the production cycle time as well as idle time. This leads to lower efficiency and subsequently lowers productivity in the organization. Furthermore, this research addresses the implementation of line balancing concepts in Almeda Garment Industry (AGI). The existing operating Garment Industries are facing problems in fulfilling targets demanded by customers, resulting in the use of overtime, to overcome the problem, thus, increasing production cost. At an earlier stage, a review of the literature on productivity and different line balancing models was conducted, from the creation of the concept of productivity to its main tools and techniques. After understanding the concepts of line balancing, a description and critical analysis of the existing system in Almeda Garment Industry was made and the problem diagnosed. Improvement scenarios were suggested relating to resources, method change, and layout arrangement.

Un terminal à conteneurs constitue une interface inter-modale importante pour le système de transport mondial. La compétitivité d'un port se mesure par l'efficacité de ses terminaux. La manutention efficace des marchandises représente un point critique de la chaîne de transport, la réduction des coûts de stockage et de gestion. Le problème de stockage de conteneurs (PSC), est l'un des plus courants et importants problèmes dans un terminal à conteneurs. L'objectif de ce problème est de créer un plan de stockage optimal qui définit l'emplacement idéal pour chaque conteneur tout en tenant compte des contraintes réelles de la zone de stockage. Dans cette thèse, nous traitons le problème du stockage de conteneurs dans un terminal portuaire, en nous concentrant sur deux cas : -Le cas statique qui vise à déterminer la meilleure stratégie de stockage pour les conteneurs importés. -Le cas critique qui consiste à trouver un plan optimal de stockage pour les conteneurs dangereux. Dans ce mémoire, nous donnons un état de l'art et une recherche bibliographique dans lesquels sont décrits les travaux antérieurs sur ce sujet. Ensuite, nous abordons respectivement les deux cas de stockage. Nous proposons une étude approfondie pour chacun d'entre eux, ainsi qu'une modélisation mathématique efficace qui modélise la situation réelle et nous détaillons les méthodes d'optimisation proposées pour résoudre ce problème. Pour effectuer une étude théorique de ce problème, nous proposons une démonstration de sa complexité, ce qui confirme encore son caractère NP-difficile. Ce type de problème est difficile à résoudre avec des méthodes exactes. Ceci est vérifié par des simulations numériques réalisées à l'aide du logiciel d'optimisation "GUROBI". Cependant, ce logiciel a des limites car il est gourmand en place mémoire, et il prend beaucoup de temps d'exécution lorsque le nombre de conteneurs à stocker devient plus grand, ce qui ajoute à la complexité du problème. En conséquence, nous avons proposé un algorithme de recherche locale itérée, un algorithme glouton randomisé, un algorithme génétique, un algorithme à base de recuit simulé et un algorithme de colonie d'abeilles comme algorithmes méta-heuristiques. Ces algorithmes proposés sont des méthodes de résolution approchées, ce qui signifie que l'optimalité des solutions qu'ils fournissent ne peut être garantie. Cependant, les comparaisons avec les résultats obtenus par « GUROBI », sur des instances de tailles raisonnables, ont démontré la bonne qualité de nos solutions. Des hybridations entre ces algorithmes méta-heuristiques distincts ont été développées afin de tirer profit de leurs avantages respectifs et d'éviter ainsi la convergence prématurée vers des optima locaux. La première hybridation proposée est une méthode qui renforce l'algorithme de recherche locale itérée par un algorithme glouton randomisé, ii tandis que la seconde est un algorithme génétique hybridé avec le recuit simulé comme opérateur de mutation. Ces hybridations ont accéléré la convergence de nos algorithmes et, dans certains cas, amélioré la qualité des meilleures solutions obtenues.

In public hospital outdoor patient services all over the world have become an important component of health care. Queuing is a major challenge for healthcare service particularly in developing countries, queuing theory helps decision making to improve waiting problem is not commonly used by managers in developing countries in contrast to their counterparts in the developed world. In this paper we introduce data analysis of observation to reduce outdoor patients waiting time without cost consideration at public hospital.

Un terminal à conteneurs constitue une interface inter-modale importante pour le système de transport mondial. La compétitivité d'un port se mesure par l'efficacité de ses terminaux. La manutention efficace des marchandises représente un point critique de la chaîne de transport, la réduction des coûts de stockage et de gestion. Le problème de stockage de conteneurs (PSC), est l'un des plus courants et importants problèmes dans un terminal à conteneurs. L'objectif de ce problème est de créer un plan de stockage optimal qui définit l'emplacement idéal pour chaque conteneur tout en tenant compte des contraintes réelles de la zone de stockage. ii tandis que la seconde est un algorithme génétique hybridé avec le recuit simulé comme opérateur de mutation. Ces hybridations ont accéléré la convergence de nos algorithmes et, dans certains cas, amélioré la qualité des meilleures solutions obtenues.

In recent years, the advancement in internet technologies has greatly altered the learning landscape, thus, a shift from traditional methods of learning to internet based learning platforms. E-learning, m-learning and cloud are some of the most powerful responses to these growing technological shift by the education sectors. Their impact and benefits cannot be overemphasized with regard to making learning accessible, affordable, available and convenient. In addition, the use of cloud technology has made the world of education more integrated, networked and composite. This makes elearning and m-learning as highly effective as the conventional method of learning delivery. However, despite these advantages, the security and the protection of learners' data on this cloud platform have been some of the major challenges to m-learning effective implementation and use. This paper discusses the various benefits of the using m-learning platform and cloud infrastructure in higher education. It also examines the vulnerabilities of the platform as well as other security and privacy challenges regarding the effective implementation of m-learning in cloud infrastructure environment. Finally, it proposes a detailed data protection and security framework that is needed for addressing these issues. It is expected that the proposed framework when fully implemented, will bring about necessary solution to issues relating to the security and data protection of m-learners in cloud computing environment, increase trust in the use of the system as well as enhance the m-learning platforms.

This paper deals with the service performance analysis and improvement using discrete event simulation has been used. The simulation of the health care has been done by arena master development 14-version software. The performance measurement for this study are patients output, service rate, service efficiency and it is directly related to waiting time of patients in each service station, work in progress, resource utilization. Simulation model was building for Bahir Dar clinic and then, prepared the proposed model for the system. Based on the simulation model run result, the output of the existing healthcare service system is low due to presence of bottlenecks on the service system. Moreover, the station with the largest queue and high resource utilization are identified as a bottleneck. The bottlenecks, which have identified are reduced by using reassigning the existing resources and add new resources and merging the similar services, which has under low resource utilization (nurses). Finally, the researchers have proposed a developed model from different scenarios. Moreover, the best scenario is developed by combining scenario 2 and 3. And then, service efficiency of the healthcare has increased by 9.86 percent, the work in progress (WIP) are reduced by 3 patients from the system and the service capacity of the system is increased 34 to 40 patients per day due to the reduction of bottleneck stations.

The typical problems facing garment manufacturers are long production lead time, bottlenecking, and low productivity. The most critical phase of garment manufacturing is the sewing phase, as it generally involves a number of operations or for the simple reason that it's labor intensive. In assembly line balancing, allocation of jobs to machines is based on the objective of minimizing the workflow among the operators, reducing the throughput time as well as the work in progress and thus increasing the productivity. Sharing a job of work between several people is called division of labor. Division of labor should be balanced equally by ensuring the time spent at each station approximately the same. Each individual step in the assembly of product has to be analyzed carefully, and allocated to stations in a balanced way over the available workstations. Each operator then carries out operations properly and the work flow is synchronized. In a detailed work flow, synchronized line includes short distances between stations, low volume of work in process, precise of planning of production times, and predictable production quantity. This study deals with modeling of assembly line balancing by combining both manual line balancing techniques with computer simulation to find the optimal solution in the sewing line of Almeda textile plc so as to improve productivity. In this research arena software, is employed to model and measure the performance of the existing and proposed sewing line of the federal police trousers sewing line model. For each operation, the researchers have taken 15 sampling observations using stopwatch and recorded the result. All the collected data are statistically analyzed with arena input analyzer for statistical significance and determination of expressions to be used to the simulation modeling; SAM is also calculated for these operations to be used to the manual line balancing. An existing systems simulation model is developed and run for 160 replications by the researchers to measure the current performance of the system in terms of resource utilization, WIP, and waiting time. The existing systems average utilization is 0.53 with a line efficiency of 42%. This study has developed a new Sewing assembly line model which has increased the system utilization to 0.69 at a line efficiency of 58.42% without incurring additional cost.

This paper deals with the service performance analysis and improvement using discrete event simulation has been used. The simulation of the health care has been done by arena master development 14-version software. The performance measurement for this study are patients output, service rate, service efficiency and it is directly related to waiting time of patients in each service station, work in progress, resource utilization. Simulation model was building for Bahir Dar clinic and then, prepared the proposed model for the system. Based on the simulation model run result, the output of the existing healthcare service system is low due to presence of bottlenecks on the service system. Moreover, the station with the largest queue and high resource utilization are identified as a bottleneck. The bottlenecks, which have identified are reduced by using reassigning the existing resources and add new resources and merging the similar services, which has under low resource utilization (nurses). Finally, the researchers have proposed a developed model from different scenarios. Moreover, the best scenario is developed by combining scenario 2 and 3. And then, service efficiency of the healthcare has increased by 9.86 percent, the work in progress (WIP) are reduced by 3 patients from the system and the service capacity of the system is increased 34 to 40 patients per day due to the reduction of bottleneck stations.

This paper deals with the service performance analysis and improvement using discrete event simulation has been used. The simulation of the heath care has been done by arena master development 14-version software. The performance measurement for this study are patients output, service rate, service efficiency and it is directly related to waiting time of patients in each service station, work in progress, resource utilization.Simulation model was building for Bahir Dar clinic and then, prepared the proposed model for the system. Based on the simulation model run result, the output of the existing healthcare service system is low due to presence of bottlenecks on the service system. Moreover, the station with the largest queue and high resource utilization are identified as a bottleneck. The bottlenecks, which have identified are reduced by using reassigning the existing resources and add new resources and merging the similar services, which has under low resource utilization (nurses...

A common problem associated with hospitals especially the nontertiary hospitals (primary and secondary hospitals) is long queue. Attempts have been made to address this using the ticket approach, however, this does not minimize crowd in and around hospitals. In the wake of the consciousness of the need to avoid crowd with the emergence of the Corona Virus (COVID-19), it has become important to note that some diseases are transmissible when people clinch close within a vicinity especially in the hospital environment. It is therefore imperative to devise a means to reduce the usual crowd witnessed at the different units/sections in the hospital, precisely by outpatients. In this study, a centralized queue control system was developed that can be used in the different sections of hospitals. The system applied Poisson Distribution, Haversine Model, Little’s Law and Kendall Notation. It is a web-based system, designed to run on the Internet as it focused on the outpatients and the fact t...

Nowadays, business manufacturers must have the ability to respond rapidly to customer demands. In order to have this power, the organization generally produces mass volumes of specific products. In mass production systems of specified products, assembly lines are generally used. In assembly production, imbalances are well-known problems. Line balancing (LB) is the leveling of the workload across all processes in a line or value stream to remove bottlenecks and excess capacity. Poor balance causes an increase in the production cycle time as well as idle time. This leads to lower efficiency and subsequently lowers productivity in the organization. Furthermore, this research addresses the implementation of line balancing concepts in Almeda Garment Industry (AGI). The existing operating Garment Industries are facing problems in fulfilling targets demanded by customers, resulting in the use of overtime, to overcome the problem, thus, increasing production cost. At an earlier stage, a rev...

The banking industry has seen a revolutionary moment in adopting mobile banking technology in the last few years. The technology has contributed to many customers keeping off the banking hall for basic and routine transactions. This has largely been attributed to the convenience of mobile banking, including time management and increased privacy. However, there are still times when a bank conducts large-scale service provision for many people. For example, a payment agency contracted by the government to disburse funds to a section of the citizens may require that money be channeled only through a particular bank. If the period for such a requirement is limited, there is likely to be pressure on both the bank and the would-be customers because of long queues. For cases like that, there is a need to simulate possible scenarios and plan to avoid delays and frustrations for both parties. This work proposes a queue simulation model that can be used to forecast the number of bank staff th...

Accurate staff scheduling is crucial in overcoming the problem of mismatch between staffing ratios and demand for health services which can impede smooth patient flow. Patient flow is an important process towards provision of improved quality of service and also improved utilization of hospital resources. However, extensive waiting times remains a key source of dissatisfaction with the quality of health care service among patients. With rarely scheduled hospital visits, the in-balance between hospital staffing and health service demand remains a constant challenge in Sub-Saharan Africa. Accurate workload predictions help anticipate financial needs and also aids in strategic planning for the health facility. Using a local health facility for a case study, we investigate problems faced by hospital management in staff scheduling. We apply queuing theory techniques to assess and evaluate the relationship between staffing ratios and waiting times at the facility. Specifically, using pati...

Supplier selection decisions require the choices of individual purchases to determine products and order quantities from certain suppliers. When suppliers are evaluated according to well-defined criteria, their level of effort and attention to detail is expected to increase significantly. This can provide to improve productivity. So, determination of supplier selection criteria that is a multi-criteria decision making process can include both quantitative and qualitative elements that are very important. In this article, the aim is to offer a fuzzy decision making method to determine leading criteria, in terms of supplier selection for an automobile company that operates in Iran, because the right suppliers that are selected according to well-defined criteria can significantly reduce the material purchasing costs and improve corporate competitiveness. For that purpose, linguistic values are used for expressing fuzzy numbers in order to assess the ratings and weights of these factors by considering criteria such as the decisions made by people who work in the purchasing department of the company. Afterward, the fuzzy TOPSIS method that is a multiple criteria decision making (MCDM) method according to fuzzy set theory is presented to cope with the determination of supplier selection criteria process. According to the results, it is determined that the following are important for supplier selection criteria for automobile firms: delivery, the amount of past business, reciprocal arrangements, warranties, and geographical location.

This paper develops a novel particle swarm optimiser algorithm. The focus of this study is how to improve the performance of the classical particle swarm optimisation approach, i.e., how to enhance its convergence speed and capacity to solve complex problems while reducing the computational load. The proposed approach is based on an improvement of Particle Swarm Optimisation using Evolutionary Game Theory. This method maintains the capability of the particle swarm optimiser to diversify the particles' exploration in the solution space. Moreover, the proposed approach provides an important ability to the optimisation algorithm, that is adaptation of the search direction which improves the quality of the particles based on their experience. The proposed algorithm is tested on a representative set of continuous benchmark optimisation problems and compared with some other classical optimisation approaches. Based on the test results of each benchmark problem, its performance is analysed and discussed.

The era of coronavirus has called for sustained social distancing measures to minimize the spread of the viral disease. Healthcare establishments are reducing the size of their working staff; while others are running their outfits base on shift work in other to ensure protocols for social distancing.  Inherent in social distancing protocol is the potential for generating waiting lines at service delivery points. Healthcare centres in many countries are already inundated with loads of patient’s attendance on daily basis for treatment off mild to severe ailments. COVID-19 has added a further burden on the already frail health systems. Whiles visits are increasing, social distancing measures are to be ensured. Quick service delivery which is an indispensable need of patients visiting hospitals for treatment is shortened. The occurrence of waiting line, an impediment to healthcare provision has become commonplace in most healthcare centres in Ghana in particular. In addition to loss of ...

Emergency department becomes a useful way to the access to hospital and it is a subject of study for many researchers. The research developed in this paper aims to improve the performance of the emergency department(ED) of Sfax Hospital by analytical method. So, a network of queues with multiple customer types is proposed. Different indicators of performance are used.

Games happen to be a part of our contemporary culture and way of life. Often mathematical models of conflict and cooperation between intelligent rational decision-makers are studied in these games. Example is the African board game ’Zaminamina draft’ which is often guided by combinatorial strategies and techniques for winning. In this paper we deduce an intelligent mathematical technique for playing a winning game. Two different starting strategies were formulated; center starting and edge or vertex starting. The results were distorted into a 3x3 matrix and elementary row operations were performed to establish all possible wins. MatLab was used to distort the matrix to determine the diagonal wins. A program was written using python in artificial intelligence (AI) to help in playing optimally

Games happen to be a part of our contemporary culture and way of life. Often mathematical models of conflict and cooperation between intelligent rational decision-makers are studied in these games. Example is the African board game ’Zaminamina draft’ which is often guided by combinatorial strategies and techniques for winning. In this paper we deduce an intelligent mathematical technique for playing a winning game. Two different starting strategies were formulated; center starting and edge or vertex starting. The results were distorted into a 3x3 matrix and elementary row operations were performed to establish all possible wins. MatLab was used to distort the matrix to determine the diagonal wins. A program was written using python in artificial intelligence (AI) to help in playing optimally

The objective of the paper is to determine customer behavior in queues in four different situations in India. The study is limited to Toll Booth-Delhi Gurgaon Highway, Health care facility for Public sector bank's staff and family, Executive check up in Health care organization and Tellers in a Bank. A detailed study of the queues at the Toll Booth on the Delhi Gurgaon expressway was done as the expressway is highly traversed and is a bottlenecked stretch. In spite of the multiple provisions to ease the traffic on this expressway, chronic delays led to a ruling by the court which made the expressway a freeway for two weeks in September 2012. The second case studied is of the work mechanism of a clinic set up for the public sector bank's staff and family in India. The doctor visits the clinic during specified hours. It was observed that one doctor caters to a large number of patients giving rise to long queues. The third case is of the hospital which has an Out Patient Department (OPD) that provides service for executive health checkup. Our study is limited to the executive health checkups, where a patient first registers and then is guided to different departments for the checkups. Lastly the study was conducted for a bank where the major business of this particular bank is retail banking for which the customer is diverted towards the tellers. Due to cost considerations and space constraint the number of tellers in a bank is limited. Inspite of the use of modern technology to streamline the queues, it is observed that during peak business hours the length of the queue increases resulting in increased waiting time for the customers. This paper attempts to do a comparative study for four different models to understand the behavior of customers waiting in queues in India.

An information technology is a part of modern society for completion of their daily schedule with sophisticated accuracy, effectiveness, efficiency and maintaining transparency. However, modern technology penetration into root level in modern Indian society is not in an appreciable in particular of rural India. Among different applications of wireless communication means a significant application is m-banking. Mobile banking mainly concerned the things of a transaction as well as financial services. In this paper, we discuss adaptation strategies and make an analysis of rural consumer behavior about mobile banking. Similarly, we discuss different mobile banking facilities and upcoming facilities which should be utilized by rural Indian people to connect rest of the world with efficiently. With that, we have a study, which factor play significant roles in rural India for deep penetration of mobile banking. As well as, study about his behavior and make an analysis of rural consumers for adaptation of beneficial technology and services to come out from a root and play at tip position in modern society. It is evident in recent time that mobile devices or handheld devices like PDA (Personal Digital Assistance) application are widespread due to its cost, ease of use, efficiency, and effectiveness. But optimum penetration exhibit inhibits by social misconception such as security and not maintain transparency before, during and after transactions.

Goodness of fit test is a test that has attracted researchers' interest over the decades. This study is on goodness of fit test for normal distribution only. The Kolmogorov-Smirnov (K-St) and Pearson's Chi-square (χ² test) goodness of fit test were used to determine the normality of a given data. The result revealed that the data is normal under the two tests and that the Kolmogorov-Smirnov (K-S test) were preferred to Pearson's Chi-square (χ² test). The Kolmogorov-Smirnov (K-S) test of goodness of fit is the most suitable in terms of the p-value.

The main objective of this study is to assess the security measures on digital banking as a basis for improving services. The researcher used a descriptive method of research, employed with the used of a standard questionnaire. Descriptive research design involves gathering data that seeks to describe events and then organizing, tabulates, depicts, and describes the data collection in a systematic manner. (Glass, G. V., & Hopkins, K. D. 1984) The survey questionnaire is divided into two parts: the demographic profile of respondents and the list of questions that the researcher aims to know in order to collect valid and reliable data needed for the study. The second part was subdivided into 3 parts, which are Security Measures on Digital Banking, Common Digital Banking Issues and Problems Encountered by Respondents, and an open-ended question about Suggestions & other problems encountered. The security measures on digital banking in terms of trust and security trust and security, kno...

The open Jackson queuing network is the open queuing network consisting of several service stations. On the open Jackson queueing networks, patients arrive from outside the network to get service and then leave the network. The open Jackson theory is used to determine the queue network model and the performance measures of each service station in the network. The data collecting technique used in this research is by interview and observation. The interview obtained a diagram of a queue network at the hospital, and the observation results consist of the number of arrival and departure data at each service station. The open Jackson queue network model is built based on a diagram of the service stages in hospitals. Furthermore, the average arrival rate and the average departure rate are substituted into the linear equation system of the formed queue network model. The linear equation system is solved using Moore-Penrose pseudo-inverse, to obtain the value of the transition probability between stations. The next steps are investigating steady-state conditions and counting performance measures. The analysis result at all service stations shows that the queueing network is a steady-state condition, such that queue performance measures can be calculated. The performance measures are the average of patients and the waiting time for patients in the queueing network.

The ability to handle uncertainty effectively is important in decision making. Whether we are uncertain about external information, the accuracy of our own knowledge, or possible outcomes, we often avoid or oversimplify uncertainties when taking decisions, especially when there are time or resource restrains. Complex models, simulations and decision aids are not always applicable. In cases where objective probability distributions are not available, the Bayesian approach allows one to operate with the decision maker’s subjective probabilities. Using strictly proper scoring rules, we are developing a game that encourages players to improve their probabilistic forecasts. The game aims to change players’ perception of uncertainty and to improve their skills in estimating, quantifying and communicating subjective probabilities and degrees of confidence. We consider psychological aspects of decision making in uncertainty and their implications for the structure, design and evaluation of ...

This paper surveys the contributions and applications of queuing theory in the field of healthcare. Tlie paper sutlmarizes a range of queuing theory results in the tbllowing aleas: waiting time and utilization analysis, system design, and appointment systems. The paper also considers results for systents at different scales, including individual departments (or units), healthcare facilities, and regional healthcare systems. information to analysts who are interested in using queuing theory to model a healthcare process and want to locate the details of relevant models. The goal is to provide sufficient

Queues are one of the worst problem in hospitals in almost all World. Patients have to wait long time even to get a small operation in hospitals in Turkey. Turkey healthcare system has recently improved, but it is still not at expected level. The quantity oriented healthcare services meaning caring more patients are not good at meeting quality parameters of healthcare services. The private sector partly subsidized by governments is more profit oriented and its share has been increasing. The quality of care can be increased by low waiting and better performance of doctors. In this study, the queuing theory applications are applied two big hospitals in Istanbul during 2013-2014 years by measuring waiting time and services time and systems during different times in six months. It is found that the performance of doctors are not at expected level when total utilization is considered. Waiting long time in queues is ignored by hospitals and these long queues create high stress over patients especially at public hospitals. Patient categorization based on appointments such as scheduled patients, checking patients, urgent patients, priority patients and new patients of day, serving different patients at district time of day, combining system of all hospitals in the same city for scheduling of surgery and other operations, decreasing waiting queues and workload on doctors can help to improve the current healthcare system.

This paper focuses on analyzing the garment processes and operation bulletin for a particular sewing line in Mahadi Fashion (PVT) Limited. The production rate of the existing layout was not close to the target. The target was 175 pieces per hour but actual production was 138 pieces per hour. So we analyzed the layout and found out the bottleneck area. Then we rearranged the workload by work sharing and reduced manpower. By doing so, actual production was 160 pieces per hour, which is near to the target, and line efficiency increased to 77%, where the existing sewing line layout was 55%. After reducing the bottleneck in sewing line capacity, we achieved 160 pieces per hour against the 138 pieces in the existing layout.

Cette étude propose d'inclure des contraintes réalistes peu prises en compte dans la littérature des plateformes logistiques, qui s'est fortement concentrée sur l'agencement des zones de stockage et les techniques de picking. L'objectif de notre travail est de concevoir des outils d'aide à la décision et des méthodes de résolution pour la planification et l'ordonnancement. Dans ce papier nous nous limitons à la partie planification. Nous proposons un modèle linéaire générique, pour lisser la charge de la plateforme et planifier la main d'oeuvre. Nous autorisons des modifications limitées (négociations) des dates d'arrivée et de départ des livraisons des fournisseurs et vers les clients. Il est possible d'embaucher du personnel additionnel et un nombre limité d'heures supplémentaires par catégorie de personnel peut être utilisé. Dans ce modèle, nous prenons en compte quelques unes des fonctions importantes d'un entrepôt, telles que des acti...

The study is a comprehensive evaluation to explore current systems and practice regarding the Patient Flow and resource utilization in an outpatient clinic in both a government and private owned hospitals in Ghana. Currently we are witnessing unprecedented queues in these hospitals. the general information was analyzed by a single-phase queuing system. Findings indicated that the estimated mean arrival rate and the waiting time at the OPD for the public hospital were 23 and 0.5 hours respectively, and 25 and 0.5 hours for private hospital and this is directly opposite queuing situations found in developed countries (Ortola, 1993).

A new Faustmann optimal rotation harvesting stands' problem under Brown geometric price and Logistic and Gompertz wood stock, diffusions is presented. The optimal cut policies for the stochastic Faustmann model and the single harvest rotation or Vicksell model are evaluated in the case of a Chilean Radiata pine forest company. The company cut policy validates the Vicksell model, its optimal cut policies overestimate the company policy cut in 1.2%, in the Gompertz case, and underestimate it in 2.3%, in the Logistic case. The Faustmann optimal cut policies present a larger underestimation of the company cut policy in 10.1%, in the Gompertz case, and in 21.5%, in the Logistic case. The preference for shorter evaluation period that the company shows is due to the organizational risk that the forest economic sectors has in Chile.

Tujuan dilakukannya penelitian ini adalah untuk mengetahui pengaruh langsung atau tidak langsung system quality terhadap user performance karyawan FEB Universitas Airlangga sebagai pengguna sistem informasi cybercampus melalui kegunaan (perceived ease of use dan perceived usefulness). Penelitian ini menggunakan sampel yang berasal dari karyawan Fakultas Ekonomi Universitas Airlangga Surabaya. Pengambilan sampel untuk penelitian ini menggunakan purposive sampling yaitu teknik pengambilan sampel berdasarkan kriteria tertentu. berjumlah 58 responden. Hasil pengujian membuktikan bahwa system quality mempunyai pengaruh signifikan terhadap user performance karyawan FEB Universitas Airlangga. Perceived usefulness dan perceived ease of use belum mampu memediasi hubungan antara system quality terhadap user performance karyawan FEB Universitas Airlangga. Information quality mempunyai pengaruh signifikan terhadap user performance karyawan FEB Universitas Airlangga. Perceived usefulness dan per...

This paper studies care provision at hospital emergency departments. It begins with a traditional approach, based on queuing theory and simulation models, and then applies a fuzzy approach to the system so as to analyse the certainty levels provided by the key parameters of the system. A real (practical) case that occurred at an emergency department is analysed using both methods. Finally, the comparative results between the traditional model and the proposed one are shown.

In this paper research was carried out in order to evaluate the security risk analysis and management in banking company through the use of a questionnaire to determine the level of risk that customer of the financial institution is likely to encounter. It was discovered that though the majority of financial institution users are familiar with the possible risk associated with some banking transaction, some aspect still exists that financial institution users are not familiar with which serves as a vulnerable point that could be exploited. The study makes a recommendation for proper enlightenment of financial institution users so as to stay abreast with possible security challenge associated with some banking transaction processes to be able to mitigate possible exploit.

The application of queueing theory to alleviate a serious congestion problem in a University Outpatient Clinic is described in this paper. The primary objective of the application was to determine, using minimization of cost (both waiting and service) as the measure of performance, the optimal number of servers that should be at the patient-personnel encounter points which had major bottlenecks. The recommendations were implemented, resulting in a substantial reduction of waiting time for patients.

Emergency department becomes a useful way to the access to hospital and it is a subject of study for many researchers. The research developed in this paper aims to improve the performance of the emergency department(ED) of Sfax Hospital by analytical method. So, a network of queues with multiple customer types is proposed. Different indicators of performance are used.

This paper focuses on analyzing the garment processes and operation bulletin for a particular sewing line in Mahadi Fashion (PVT) Limited. The production rate of the existing layout was not close to the target. The target was 175 pieces per hour but actual production was 138 pieces per hour. So we analyzed the layout and found out the bottleneck area. Then we rearranged the workload by work sharing and reduced manpower. By doing so, actual production was 160 pieces per hour, which is near to the target, and line efficiency increased to 77%, where the existing sewing line layout was 55%. After reducing the bottleneck in sewing line capacity, we achieved 160 pieces per hour against the 138 pieces in the existing layout.

A cellular manufacturing system (CMS) is a suitable system for the economic manufacture of part families. Scheduling the manufacturing cells plays an effective role in successful implementation of the manufacturing system. Due to the fact that in the CMS, bottleneck machine and human resources are two important factors, which so far have not been studied simultaneously in a mathematical model, there should be a model to consider them. Therefore, this research develops a bi-objective model for CMS in a three-dimensional space of machine-part and human resources. The main objective is to minimize the maximum completion time of all tasks in the system and reduce the number of intercellular translocation based on bottleneck machines’ motion and human resources. Due to the NP-hardness of the studied problem, applying the conventional solution methods is very time-consuming, and is impossible in large dimensions. Therefore, the use of metaheuristic methods will be useful. The accuracy of ...

In many hospitals, Patients wait for long time in the healthcare facility before they are attended to by the health personnel. This trend is on the increase and it is a potential threat to healthcare services. In Nigeria, specialist, teaching and general hospitals with large number of patients have cases where patients may not be attended to on time while others may end up going home without receiving medical attention. An efficient queuing model for proper appointment system is proposed as the solution to the long waiting times in these hospitals in this paper. The appointment queuing system provides better utilization of resources and reduces patients waiting times in the general outpatient department before consultation with the Doctor. Arrival rate and pattern, availability of medical services and preferences, employees experience and availability of information technology are factors that affect the performance of an appointment system. This research work provides an efficient ...

This paper represents the use of some tools and techniques for improving apparel sewing section efficiency throughout the production process. Now a day's apparel manufacturing industries are trying to develop their current production system and situation and continuously looking for new production tools and techniques in order to keep swiftness with the rapid changes of trend in consumers of apparel products. To deal with the recent problems & challenges industries have to improve production efficiency & productivity; reduce lead time, ensuring proper quality requirements. There is no doubt that sewing section in an apparel industry is the most momentous and teeming department that plays a vital role in the whole firm. To improve the existing situation of this section and increasing productivity time study is a very effective technique. In time study, Standard Minute Value (SMV) has been calculated for each operation or job. Based on this technique each operators capacity is measured and balanced to eliminate the bottlenecks. Here, by applying these techniques significant improvements in the sewing section have been achieved such as SMV, man power, bottle neck, capacity achievable, production/hr, performance rating, balance % and line efficiency. The findings can be extended to similar apparel industries in future. General overviews to these works are presented in this paper.

Perencanaan BTS adalah salah satu bagian yang penting dalam perencanaan jaringan Telkom Flexi, dimana dengan perencanaan BTS yang baik akan memberikan kualitas layanan yang lebih baik bagi seluruh sistem. Banyak faktor yang mempengaruhi dalam perencanaan BTS flexi, salah satunya yaitu memperhitungkan cakupan pelanggan, apakah pelanggan di daerah tersebut sudah semua terlayani. Perencanaan BTS Flexi di Bandung sangat diperlukan untuk menjaga kualitas sinyal yang diterima pelanggan, dan untuk menghindari adanya blank spot, serta kemudahan operator dalam penentuan lokasi.Sistem Informasi Geografis atau biasa disebut GIS (Geographic Information System) merupakan salah satu tools yang dapat dipakai untuk memetakan lokasi BTS dengan memperhitungkan peramalan demand, jumlah user per BTS, loss propagasi, radius BTS serta perhitungan dengan metode Integer Linier Programming. GIS merupakan tool yang dapat mengumpulkan, menyimpan, mengintegrasikan, mengolah, dan menganalisis objek-objek dan fe...