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In this article, focus on the simulation of a three-phase perishable product inventory system of a SMEs selling fresh and processed milkfish. This research was conducted to simulate a perishable product inventory system to understand and analyze the problems that occur then propose solutions to fix them. The simulation model was developed with ARENA software, simulation results of the existing condition show that there is 162 kg/month waste in fresh fish, 158 pcs/month in processed product A, and 86 pcs/month in processed product B. A model with a product renewal process mechanism was proposed to overcome this problem, and seven improvement scenarios were developed. The results obtained from the seventh improvement scenario revealed that there was a 100% reduction in fresh fish and processed product B and 94% in processed product A. Besides, there was a saving in need for fresh fish supply of 10 kg/day. In this article, we show how ARENA software can be adopted to simulate inventory system problems effectively. The method in this research can be applied to investigate various supply system scenarios and their consequences before implementing it in a real system.

The management of university libraries in Indonesia has been intervened from foreign institutions through a donation of library materials which seem for the benefit of the academic community , but it is for the benefit of the donors. Academicians, especially the young generation, are a target of donation whether as the readers of books donated to the University or as the audience of programs or activities funded by donor agencies. Based on the background, it is found how the library becomes an arena for the contestation of various interests through some “corners” build inside the University Libraries. Using the concepts introduced by Pierre Bourdieu such as arena and capitals. Supported by Vincent Mosco’s theory of political economy of communication as the tools of analysis, this research reveals how the agents involved in the management of the “Corner” use the library as an "arena" to achieve their benefits. The data obtained were grouped based on the sub-theme of types capital, commodification, specialization and structuration Using phenomenological approach , it is found that Corners in the university Libraries are used as an arena of contestation of agents involved in governance to foster capital. Contestation in this study illustrates the phenomenon of actors involved in the management of Corner into the dominant-subordinate relationship.

This study analyzes a stochastic continuous review inventory system (Q,r) using a simulation-based optimization model. The lead time depends on lot size, unit production time, setup time, and a shop floor factor that represents moving, waiting, and lot size inspection times. A simulation-based model is proposed for optimizing order quantity (Q) and reorder point (r) that minimize the total inventory costs (holding, backlogging, and ordering costs) in a two-echelon supply chain, which consists of two identical retailers, a distributor, and a supplier. The simulation model is created with Arena software and validated using an analytical model. The model is interfaced with the OptQuest optimization tool, which is embedded in the Arena software, to search for the least cost lot sizes and reorder points. The proposed model is designed for general demand distributions that are too complex to be solved analytically. Hence, for the first time, the present study considers the stochastic inventory continuous review policy (Q,r) in a two-echelon supply chain system with lot size-dependent lead time L(Q). An experimental study is conducted, and results are provided to assess the developed model. Results show that the optimized Q and r for different distributions of daily demand are not the same even if the associated total inventory costs are close to each other.

Stadiums have recently become one of the most important issues in the economy of professional football clubs with its positive and negative effects. Football rapidly developing worldwide is social, cultural and economic phenomenon and is one of the world's most profitable sports. The transformation of an economics of billion dollars and the transformation of an industrial character from the beginning of the 1990s has caused all eyes to be turned over to the stadiums as a place of production of football over time. Stadiums in the process of industrial transformation of football have transformed into structures that live 365 days and generate significant monetary income, including non-football events. Now the conversion of soccer fans to a "consumer spectators" has led to a new comfort structure that will increase the added value of the clubs' stadiums per seat. In this way, the match day revenues, which will hold an important place in the monetary revenues of football, also started to increase its share in total revenues rapidly. Although this share has increased, because the seat capacity is fixed it has forced the clubs to become even more creative in these matters. Soccer clubs have started to design stadiums in this sense in a way that will make them more functional and monetary. Today, soccer stadiums have grown out of a simple structure and they have become the production center of industrial football and the most important source of income. The income generated by the stadiums is now approaching nearly 40 percent of European soccer revenue. The aim of the study is to examine economic and social efficiency of stadiums and arenas which is a significant source of revenue for professional football clubs and is to examine the economic effects of Turkish football stadiums and arenas in Turkey.

A major problem connected with planning the organization of trains in metros is the optimization of the scheme of movement, which determines the routing and the number of trains. In this paper, a combined simulation-optimization model including four steps is proposed. In the first step, the train movement has been simulated in order to study the interval between the trains according to the incoming passenger flows at the stations. The simulation model was elaborated using the ARENA software. The results were validated through experimental observations. Using the results obtained from simulations in the second step the correlation between the observed parameters - the incoming passengers and the interval between trains - has been studied. Recent research has established a non-linear relationship between the interval of movement, incoming passengers at the station and passengers on the platform. The third step defines the variant schemes of transportation. The fourth step presents the optimal choice of transportation of trains in metros based on linear optimization model. The model uses the regression obtained in the second step. The practicability of the combined simulation-optimization model is demonstrated through the case study of Sofia’s metro in two peak periods – morning and evening. The model results and the real situation have been compared. It was found that the model results are similar to the real data for the morning peak period but for the evening peak period it is necessary to increase the number of trains.

Modelling and simulation of industrial systems have become a conventional method for productivity improvement through optimizing design, operation, performance and troubleshooting. This paper analyses the current Shearcut process flow through modelling and simulation. A case study research was undertaken at a steel processing company that transform steel coils into sheets, plates, slits, tubes, blanks and various roofing products. Two models were created using Arena software. The models were a representation of the process flow found in the Shearcut warehouse. The first model was developed from data obtained from production records and time studies that were carried out on some of the operations. Bottleneck stations and non-value adding operations were identified. The second model was created with some improvements that included reduced non-value adding times. Results from the second model had an improved output. This paper contributes to the use of computer simulation as a tool to improve productivity.

International audience; This paper focuses on coupling of simulation and optimization techniques, both representing an integrated part of modern design and supervision practices in management sciences, industry and engineering. After discussing the different possible connotations of the concept of simulation optimization coupling, we explicitly describe the integration of two commercial-off-the-shelf (COTS) industry-standard software tools ARENA and CPLEX, respectively. Being written in the continuity of the earlier published work by Vamanan et al. (2004), the contribution of the present article is threefold: (i) elucidating the coupling of simulation and optimization, considered as two complementary decision helping approaches, (ii) explaining explicitly the software integration of the latest versions of ARENA and CPLEX, (iii) pointing out the undeniable usefulness of such tools tandem.

Ocaktan, Mustafa Ahmet Beyazıt (Balikesir Author), Stochastic operation times make job-shop scheduling harder at companies which work based on project type labor-intensive production in a dynamic environment. The operation times are not known before production and change based on the orders' technical specifications. In performing required operations with the aim of producing a final product, scheduling is required for different purposes such as minimizing makespan, maximizing resource utilization, etc. This is important as it enables companies to meet customer demands by due date and reduce the labor cost on the finalized product. In this study, an order scheduling algorithm is proposed for nearly optimizing average makespan for several waiting orders in a transformer company's core production workshop considering dynamical production environment. The proposed algorithm adopts the technical order specifications, computes the stochastic operation times making use of simulation, and schedule orders using one of the widely used meta-heuristics, namely genetic algorithm. The objective is to determine the entry sequence of the waiting orders to the core production workshop for minimizing their average makespan which directly influences the resource utilization, efficiency, and labor costs.

Este trabajo tuvo por objetivo evaluar la arena (A), el carbón activado (CA) y la zeolita (Z) como materiales filtrantes para valorar su efecto en reutilización para agricultura de aguas residuales tratadas de un ambiente árido. Para esto se construyeron 7 columnas de filtración: a) columna 1, 100 % de Z, b) columna 2, 100 % de CA (origen A), c) columna 3, 100 % de CA (origen B), d) columna 4, 100 % de A, e) columna 5, 50 % de Z sobre 50 % de CA, f) columna 6, 50 % de A sobre 50 % de CA, y g) columna 7, 50 % de Z sobre 50 % de A. En el afluente y efluente se evaluó boro (B), cloruro (Cl-), sulfato (SO4-2), calcio (Ca+2), conductividad eléctrica (CE), pH y temperatura (T), junto a un grupo de metales pesados (As, Cd, Cu, Fe, Mn, Pb y Zn). Los resultados mostraron cómo el CA (de origen A o B) es capaz de remover boro a valores por debajo de 0,75 mg/L. Sin embargo, en una etapa inicial (primera quincena) los efluentes a este medio filtrante, presentaron un valor de CE mayor a 2,5 dS/m, y de pH mayor a 8,4, lo que seguramente traerá problemas para su aplicación en riego de cultivos. Por su parte, la arena, al ser de la región, presenta problemas de lixiviación de elementos, como el arsénico y el sodio, por lo que no debería utilizarse como material filtrante. Por el contrario, el único medio evaluado que tiene potencial de ser aplicado en la reducción de la salinidad es la zeolita. Este material filtrante, sin mezcla con otro, fue capaz de reducir hasta un 20 % el valor de la CE sin tener un efecto negativo en ninguno de los otros parámetros evaluados en este estudio, y además, sin mostrar un estado de saturación durante el tiempo de operación evaluado. En el caso de las columnas que utilizaron mezclas de materiales, no existe un efecto sinérgico para la eliminación de los parámetros de calidad del agua evaluados.

Swimsuit development took a massive leap forward in 2008 with the introduction of full body suits and again in 2009 with the development of the’Speedo LZR’ suits with polyurethane panels and later with all polyurethane suits such as the’Arena X-Glide’. The improvements seen in swimsuit technology were accompanied by a significant rise in elite performance across the majority of the swimming events. The unprecedented numbers of World records being set at the 2008 Beijing Olympics Games and the 2009 Rome World Swimming Championships led FINA, the governing body of swimming to question the use of the swimsuits. Following the investigation, new swimsuit specifications were implemented and took effect from January 1st 2010. The new regulations effectively banned all advances in swimsuit technology. The top 25 times in each year going back to 1948 were used to assess the effects of swimsuit technology using a performance improvement index. This allowed a 5-parameter regression model to be created to quantify the size of the step changes in performance caused by the new swimsuits. The following was found: the introduction of full body swimsuits in 2000 increased performance in the men's freestyle between 0.9 and 1.4%; the introduction of polyurethane panels in 2008 increased performance by an additional 1.5-3.5%. The use of full body polyurethane suits in 2009 increased this performance further and by up to 5.5%. The women's freestyle showed similar but smaller increases in performance and the performance advantage of the suits was most evident in the sprint events. It was hypothesized that the suits reduced the cross sectional area of the swimmer and the drag coefficient CD leading to a reduction in the drag force. The increase in performance may have been reduced by the fatiguing effect of the relatively stiff swimsuits which would have impacted more in the longer events with a large number of turns.

This paper considers mutual imaging of aid workers and Bhutanese refugees in Nepal. Based on a theoretical perspective of aid as a socially negotiated arena, the contextual and interactionist concept of imaging is used, rather than labelling (which is done to people), or perceptions (located in one actor's head). The paper uses a Q-methodology that symmetrically researches different groups of actors by posing the same questions. Our data confirm that the distinctions between the way aid workers and recipients view themselves, each other and the aid provided were more gradual than clear-cut between categories and that the legitimacy of aid workers is not determined by the perceived quality of aid. Problems with routinised aid were not translated into negative images, whereas problems with new and irregular types of aid were. Our research indicates the importance of the interaction between implementing staff and active beneficiaries. The roles of these active volunteers and incentive workers are important but ambiguous. They may smooth the divide between aid agencies and clients, but their proximity to the aid regime may also lead to tensions. The way these roles are played out and the effect this has on imaging and aid legitimacy is an area for further research

This research was carried out at the Motor Vehicle Periodic Inspection (MVPI) station to improve and enhance the bottleneck inspection point by using different applications to reduce the inspection time. The main problem of this research was an inspection point (No. 1) which consumed more time in comparison with the other inspection points. Accordingly, this inspection point increases the flow time in the inspection lanes. This research investigated and searched for possible solutions and alternatives aimed at achieving the objective using some tools from motion and time study and ARENA software to simulate and predict the changes expected to occur in the inspection lanes. Overall, the suggested alternatives yielded an expected improvement of 174.8% in the production capacity.

A real manufacturing system of an electronic company was mimicked by using a simulation model. The effects of dispatching rules and resources allocations on performance measures were explored. The results indicated that the dispatching rules of shortest processing time (SPT) and earliest due date are superior to the current rule of first in first out adopted by the company. A new combined rule, the smallest quotient of dividing shortest remaining processing time (SRPT) by SPT (SRPT/SPT_Min), has been proposed and demonstrated the best performance on mean tardiness time under the current resources situation. The results also showed that using fewer resources can increase their utilization, but it increases the risk of delivery tardiness as well, which in turn will damage the organization’s reputation in the long run. Some suggestions for future work were presented.

This paper describes a logistic study about an underground gold mine, belonging to AngloGold Ashanti, where four different layout options could be applied to the tunnels, and also different transportation strategies. Each evaluated layout had its own configuration for shaft and truck fleets. The study was made individually for each year of the mine operation life, determining the necessary transportation capacity to achieve the planned production for that year. Due to the very restrictive traffic options in the tunnels, a framework was developed to represent the tunnels and traffic rules in a discrete-event simulation model. The results pointed the scenario with the lowest necessary transportation capacity to achieve the planned production. Esse artigo descreve o estudo de logística de uma mina subterrânea, pertencente à AngloGold Ashanti, em que quatro alternativas de transporte foram estudadas. Cada alternativa teve uma configuração específica para frota, silos e poço. O estudo foi feito individualmente para cada ano de operação da mina e determinou a capacidade de transporte necessária para se atingir a produção planejada naquele ano. Devido à especificidade do transporte e regras de tráfego do modelo, optou-se por utilizar o software de simulação ARENA. Os resultados apontaram o cenário com o menor número de frota e a maior capacidade de transporte para realizar o plano de produção.

Nutritional sciences are discovering the application of the so-called 'omics' sciences. Propelled by the recent unravelling of the human genome and the coinciding technological developments, genotyping, transcriptomics, proteomics and metabolomics are now available to nutritional research. In the future we are likely to see new screening tools for the selection of bioactive nutrients, new biomarkers for the in vivo efficacy of nutrients, and better insight into the influence of genetic polymorphisms on nutrient metabolism. However, are these promises just based on biotechnological hype or is a real fundamental change in human nutritional sciences at hand? Chemicals/CAS: Biological Markers

A new research model for simulation software evaluation is proposed consisting of three main categories of criteria: modeling and simulation capabilities of the explored tools, and tools’ input/output analysis possibilities, all with respective sub-criteria. Using the presented model, two discrete event simulation tools are evaluated in detail using the task-centred scenario. Both tools (Arena and ExtendSim) were used for teaching discrete event simulation in preceding academic years. With the aim to inspect their effectiveness and to help us determine which tool is more suitable for students i.e. academic purposes, we used a simple simulation model of entities competing for limited resources. The main goal was to measure subjective (primarily attitude) and objective indicators while using the tools when the same simulation scenario is given. The subjects were first year students of Master studies in Information Management at the Faculty of Economics in Split taking a course in Business Process Simulations (BPS). In a controlled environment – in a computer lab, two groups of students were given detailed, step-by-step instructions for building models using both tools - first using ExtendSim then Arena or vice versa. Subjective indicators (students’ attitudes) were collected using an online survey completed immediately upon building each model. Subjective indicators primarily include students’ personal estimations of Arena and ExtendSim capabilities/features for model building, model simulation and result analysis. Objective indicators were measured using specialised software that logs information on user's behavior while performing a particular task on their computer such as distance crossed by mouse during model building, the number of mouse clicks, usage of the mouse wheel and speed achieved. The results indicate that ExtendSim is well preferred comparing to Arena with regards to subjective indicators while the objective indicators are better for Arena. Objectively, students completed the given scenario faster and with fewer movements in Arena, but they still prefer ExtendSim and perceive it as a better tool considering the characteristics and functionalities.

“Classic” kernel density estimations (KDE) can display static densities representing one point in time. It is not possible to visually identify which parts of the densities are moving. Therefore, within this paper we investigate how to display dynamic densities (and the density changes) to identify movement patterns. To deal with a temporal dimension (in our case study a dynamic crowd of individuals) we investigated the application of directed kernel density estimation (DKDE). In a case study we apply the DKDE to a point dataset presenting individuals approaching the Allianz Arena in Munich, Germany, with different speeds from different directions. Calculating the density using a directed kernel with this data, results in a density map indicating the movement direction with a visible “ripple” effect. Ripples move at different rates to the substances in which they occur. That tells us something about crowd dynamics and enables us to visually recognize the parts of the crowds that are moving plus the underlying movement directions.

This research’s title is Estetika Sastra Populer d Novel Mencari Sarang Angin Karya Suparto Brata. This research is aiming to elaborate the story of Mencari Sarang Angin by Suparto Brata. This research is done because Suparto Brata and his novels are containing historical story but, different with the other historical novels, appreciation and legitimation that received by Suparto Brata is not relatively significant.Mencari Sarang Angin is one of Suparto Brata’s popular work, that is the reason why this work becomes the object study. There are some theories that is used, they are cultural production by Bourdieu and detective formula theory. According to this research, there are two findings, they are dominant love story as the main story, also utilization of detective story formula as the structure of story telling.

In recent years, the attention focused on the study of bus rapid transit (BRT) systems has been growing significantly because they improve mobility without underestimating sustainable mobility issues. First, an overview of literature on the available analytic models for performances analysis of BRT systems has been carried out. Then, a new dynamic microsimulation model has been implemented by Arena Rockwell Software to simulate and evaluate different BRT systems configurations. Validation is done achieving a comparison between model's results and those obtained by an analytic model. Finally, the model has been applied in a real-life case study for a new BRT line in Rome.

This paper presents a simulation experiment comparing the Single Stage, Single Product Base Stock (BS), Traditional Kanban Control System (TKCS) and Extended Kanban Control System (EKCS). The results showed that BS incurs the highest cost in all scenarios; while EKCS is found to be effective only in a very niche scenario. TKCS is still a very powerful factory management system to date; and EKCS did not perform exceptionally well. The only time EKCS did outperform TKCS was during low demand arrival rates and low Backorder (Cb) and Shortage costs (Cs). That is because during then, it holds no stock. The most important discovery made here is that EKCS becomes TKCS once it has base stock (or dispatched kanbans). The results have also evinced the strength of the pure kanban system, the TKCS over BS. Hence managers using BS should consider upgrading to TKCS to save cost.

Where the other papers in this special edition of Internet Archaeology look at the experiences and achievements of the ARENA project this paper looks to the future. Portal technologies like those used by the ARENA portal are already moving into new and exciting areas, areas such as web services and portlet technologies in particular. This paper considers the work of the ADS in projects such as ARENA, but also HEIRPORT and CREE, work that has revealed new and exciting paths towards data sharing on a European scale. Are these the paths that any new ARENA project will have to follow to sustain the dream of interoperable data sharing for European archaeology?

The ARENA project has brought the idea of a common European heritage web resource closer. With sites and monuments data from six nations available for interoperable search valuable insight has been gained into the technical and other difficulties involved resulting in a clear view to the next logical steps. Drawing in a discussion of the status for internet use within the sector of cultural heritage in Denmark a number of perspectives for using the internet for cultural heritage management and information dissemination is drawn up. Denmark is offered as an example, others could probably be found.

The ARENA project was created to confront issues of data preservation and archiving, dissemination and European information interoperability in archaeology. In achieving these goals the project raised many issues that deserve deeper discussion. This paper provides some of this discourse considering aspects of: European identity and projects funded by European money; The importance of technical and human networking to interoperability; Dealing with Language; Spatial Issues; Describing Data, the role of Metadata; Digitisation of historic data; Preservation and Publication. This paper sets out to draw together these vital pathways that must all be followed if archaeology and heritage management in Europe is to be served by a suitable network and information infrastrucure. Some of the issues raised here have a resonance in other papers in this ARENA special edition of Internet Archaeology, others are discussed in greater detail elsewhere.

Esse artigo descreve um conjunto de módulos, do Template Mineração 1.0, que foi desenvolvido para utilização no programa ARENA, visando a melhorar a modelagem e a simulação de operações de carregamento e transporte em minas a céu aberto. Os módulos representam atividades de lavra, tais como carga, descarga, deslocamento vazio e carregado dos caminhões, além de paradas para manutenção dos equipamentos. Os sistemas de alocação dinâmica de caminhões, atualmente presentes em boa parte das minas, também possuem um módulo específico. Através de testes realizados com dados reais, o Template mostrou-se de uso bastante amigável e apresentou resultados satisfatórios quando comparado com a operação real e com resultados de outro simulador. This article describes a group of blocks of Template Mining 1.0, developed to be used with ARENA System. The objective is to improve modeling and simulation of open pit mining operations. The blocks represent the essential activities of open pit mining, like loading, unloading, loaded and unloaded haulage and equipment maintenance. The dynamic allocation system of trucks, nowadays used in the mining companies can also be represented. The Template has a friendly interface and it has been tested with real data. These tests have produced satisfactory results, which are similar to other simulation system.

Discrete-event simulation has been widely used technique in analyzing construction operations for the past three decades due to its great effect on optimizing cost and productivity. In this paper we will present Arena as a tool for simulating earthwork operations, the advantage of Arena is its easiness and flexibility in simulating most kinds of models in different areas of construction. A case study will be presented, a model will be built and results obtained to reveal the mentioned objectives.

A certain manufacturing plant is in the business of manufacturing plastic products majority of which are crates and pallets. After molding, pallet parts are welded together using welding machines. Recently, to increase productivity and reduce costs, the pallet welding process has omitted the cutting step. A previous study was done to determine the optimal number of pallets welded per shift with the cutting process. This study compares the old process and the new process using simulation software, Arena. The result of the simulation shows a 25% improvement in terms of the number of pallets produced per shift from 180 to 226. Based on the worker utilization of the process, there are some workers who are underutilized; therefore one option is to do line balancing. Based on the results of the line balancing, one worker can be removed by combining the job of two workers. The combination of the job of the two results to an increase in the worker utilization without compromising the amount of pallets produced.