Search results for: inventory.
150 Oil Refineries Emissions: Source and Impact: A Study using AERMOD
Authors: Amir. AL-Haddad, Hisham. Ettouney, Samiya. Saqer
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The main objectives of this paper are to measure pollutants concentrations in the oil refinery area in Kuwait over three periods during one year, obtain recent emission inventory for the three refineries of Kuwait, use AERMOD and the emission inventory to predict pollutants concentrations and distribution, compare model predictions against measured data, and perform numerical experiments to determine conditions at which emission rates and the resulting pollutant dispersion is below maximum allowable limits.Keywords: Emissions, ISCST3 model, Modeling, Pollutants, Refinery
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1618149 Curriculum and Sex-specific Differences in Academic Stress Arising from Perceived Expectations
Authors: Glenn M. Calaguas
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With the aim of knowing whether curriculum and sex differences exist in academic stress arising from perceived expectations, high school students were asked to respond to the Academic Expectations Stress Inventory (AESI). AESI is a nine-item inventory with two domains, namely: expectations of teachers/parents and expectations of self. Out of the 504 officially enrolled high school students in a state college, 469 responded to the inventory. Responses were analyzed using independent samples ttest. Significant differences were found between the mean scores of the respondents coming from the Science and the Vocational curriculum. The respondents from the Science curriculum consistently registered higher mean scores. Likewise, significant differences were found between the male and the female respondents. The female respondents consistently registered higher mean scores.Keywords: academic stress, curriculum and sex differences, high school students, perceived expectations
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2162148 Verifying Environmental Performance through Inventory and Assessment: Case Study of the Los Alamos National Laboratory Waste Compliance and Tracking System
Authors: O. S. Saulters, S. D. Goldberg, W. A. Staples, E. I. Martinez, L. M. Sanchez, D. E. Archuleta, D. L. Williams, S. D. Johnson, A. M. Baker
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To address an important set of unverified field conditions, the Los Alamos National Laboratory Waste Compliance and Tracking System (WCATS) Wall-to-Wall Team performed an unprecedented and advanced inventory. This reconciliation involved confirmation analysis for approximately 5850 hazardous, low-level, mixed low-level, and transuranic waste containers located in more than 200 staging and storage areas across 33 Technical Areas. The interdisciplinary team scoped, planned, and developed the multidimensional assessments. Through coordination with cross-functional site hosts, they were able to verify and validate data while resolving discrepancies identified in WCATS. The results were extraordinary with an updated inventory, tailored outreach, more cohesive communications, and timely closed-loop feedbacks.
Keywords: Circular economy, environmental performance data, social-ecological-technological systems, waste management.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 479147 The Effects of Work Values, Work-Value Congruence and Work Centrality on Organizational Citizenship Behavior
Authors: Başak Uçanok
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The aim of this study is to test the “work values" inventory developed by Tevruz and Turgut and to utilize the concept in a model, which aims to create a greater understanding of the work experience. In the study multiple effects of work values, work-value congruence and work centrality on organizational citizenship behavior are examined. In this respect, it is hypothesized that work values and work-value congruence predict organizational citizenship behavior through work centrality. Work-goal congruence test, Tevruz and Turgut-s work values inventory are administered along with Kanungo-s work centrality and Podsakoff et al.-s [47] organizational citizenship behavior test to employees working in Turkish SME-s. The study validated that Tevruz and Turgut-s work values inventory and the work-value congruence test were reliable and could be used for future research. The study revealed the mediating role of work centrality only for the relationship of work values and the responsibility dimension of citizenship behavior. Most important, this study brought in an important concept, work-value congruence, which enables a better understanding of work values and their relation to various attitudinal variables.Keywords: Work values, work-value congruence, work centrality, organizational citizenship behavior.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3716146 Influence of Radio Frequency Identification Technology in Logistic, Inventory Control and Supply Chain Optimization
Authors: H. Amoozad-khalili, R. Tavakkoli-Moghaddam, N.Shahab-Dehkordi
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The main aim of Supply Chain Management (SCM) is to produce, distribute, logistics and deliver goods and equipment in right location, right time, right amount to satisfy costumers, with minimum time and cost waste. So implementing techniques that reduce project time and cost, and improve productivity and performance is very important. Emerging technologies such as the Radio Frequency Identification (RFID) are now making it possible to automate supply chains in a real time manner and making them more efficient than the simple supply chain of the past for tracing and monitoring goods and products and capturing data on movements of goods and other events. This paper considers concepts, components and RFID technology characteristics by concentration of warehouse and inventories management. Additionally, utilization of RFID in the role of improving information management in supply chain is discussed. Finally, the facts of installation and this technology-s results in direction with warehouse and inventory management and business development will be presented.Keywords: Logistics, Supply Chain Management, RFIDTechnology, Inventory Control.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1835145 A Comparative Analysis of the Perceived Bureaucracy in a Turkish State University
Authors: Ahmet C. Kutlu, Seçkin Polat
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Organizational structure of the Turkish state universities is a form of bureaucracy, a high efficient system in rational and formal control. According to the dimensional approach bureaucracy can occur in an organization in a degree, as some bureaucracy characteristics can be stronger than others. In addition, the units of an organization due to their different specific characteristic properties can perceive the bureaucracy differently. In the study, Hall-s Organizational Inventory, which was developed for evaluating the degree of bureaucratization from the dimensional perspective, is used to find out if there is a difference in the perception of the bureaucracy between the academicians working in three different departments and two faculties in the same university.Keywords: Degree of bureaucratization, Hall's Organizational Inventory, perceived bureaucracy.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1269144 Floristic Richness of the Tropical Coast of Northern Andhra Pradesh along Bay of Bengal, a Treasure to be Conserved
Authors: Rao M. V., Joshi S. C., Balaji M.
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Coastal zone combines terrestrial, marine and atmospheric factors and gives rise to unique landforms that play an important role in long-term sustainability of the hinterland and economy of maritime nations. World over, efforts have been put forth to understand plants of the seacoasts. In India also, plants of several geographical entities have been well documented, but works devoted to plant communities of the vast tropical coast of India and its States are still insufficient. Therefore, an inventory of plants flourishing in a stretch of ~450km of the Coastal Regulatory Zone I encompassing a total of 84 villages in 6 revenue Districts of northern Andhra Pradesh (15o42’06”N, 80o51’03”E to 19o05’51”N, 84o47’44”E) along Bay of Bengal was carried out. The study revealed presence of a total of 364 species belonging to 225 genera under 71 families. In addition to inventory, zonation pattern, ethnobotany, and certain interesting ecological facts are included.
Keywords: Ecology, Ethnobotany, Inventory, Tropical coast, Zonation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3858143 Scheduling Maintenance Actions for Gas Turbines Aircraft Engines
Authors: Anis Gharbi
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This paper considers the problem of scheduling maintenance actions for identical aircraft gas turbine engines. Each one of the turbines consists of parts which frequently require replacement. A finite inventory of spare parts is available and all parts are ready for replacement at any time. The inventory consists of both new and refurbished parts. Hence, these parts have different field lives. The goal is to find a replacement part sequencing that maximizes the time that the aircraft will keep functioning before the inventory is replenished. The problem is formulated as an identical parallel machine scheduling problem where the minimum completion time has to be maximized. Two models have been developed. The first one is an optimization model which is based on a 0-1 linear programming formulation, while the second one is an approximate procedure which consists in decomposing the problem into several two-machine subproblems. Each subproblem is optimally solved using the first model. Both models have been implemented using Lingo and have been tested on two sets of randomly generated data with up to 150 parts and 10 turbines. Experimental results show that the optimization model is able to solve only instances with no more than 4 turbines, while the decomposition procedure often provides near-optimal solutions within a maximum CPU time of 3 seconds.
Keywords: Aircraft turbines, Scheduling, Identical parallel machines, 0-1 linear programming, Heuristic.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2002142 Stochastic Optimization of a Vendor-Managed Inventory Problem in a Two-Echelon Supply Chain
Authors: Bita Payami-Shabestari, Dariush Eslami
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The purpose of this paper is to develop a multi-product economic production quantity model under vendor management inventory policy and restrictions including limited warehouse space, budget, and number of orders, average shortage time and maximum permissible shortage. Since the “costs” cannot be predicted with certainty, it is assumed that data behave under uncertain environment. The problem is first formulated into the framework of a bi-objective of multi-product economic production quantity model. Then, the problem is solved with three multi-objective decision-making (MODM) methods. Then following this, three methods had been compared on information on the optimal value of the two objective functions and the central processing unit (CPU) time with the statistical analysis method and the multi-attribute decision-making (MADM). The results are compared with statistical analysis method and the MADM. The results of the study demonstrate that augmented-constraint in terms of optimal value of the two objective functions and the CPU time perform better than global criteria, and goal programming. Sensitivity analysis is done to illustrate the effect of parameter variations on the optimal solution. The contribution of this research is the use of random costs data in developing a multi-product economic production quantity model under vendor management inventory policy with several constraints.Keywords: Economic production quantity, random cost, supply chain management, vendor-managed inventory.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 684141 An Optimization Modelling to Evaluate Flights Scheduling at Tourist Airports
Authors: Dimitrios J. Dimitriou
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Airport’s serving a tourist destination are an essential counterpart of the tourist demand supply chain, and their productivity is related to the region’s attractiveness and is enhanced by the air transport business. In this paper, the evaluation framework of the scheduled flights between two tourist airports is taken into consideration. By adopting a systemic approach, the arrivals from an airport that its connectivity heavily depended on the departures of another major airport are reviewed. The methodology framework, based on inventory control theory and the numerical example, promotes the use of the modelling formulation. The results would be essential for comparison and exercising to other similar cases.Keywords: Airport connectivity, inventory control, optimization, optimum allocation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 958140 Performance Determinants for Convenience Store Suppliers
Authors: Zainah Abdullah, Aznur Hajar Abdullah
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This paper examines the impact of information and communication technology (ICT) usage, internal relationship, supplier-retailer relationship, logistics services and inventory management on convenience store suppliers- performance. Data was collected from 275 convenience store managers in Malaysia using a set of questionnaire. The multiple linear regression results indicate that inventory management, supplier-retailer relationship, logistics services and internal relationship are predictors of supplier performance as perceived by convenience store managers. However, ICT usage is not a predictor of supplier performance. The study focuses only on convenience stores and petrol station convenience stores and concentrates only on managers. The results provide insights to suppliers who serve convenience stores and possibly similar retail format on factors to consider in improving their service to retailers. The results also provide insights to government in its aspiration to improve business operations of convenience store to consider ways to enhance the adoption of ICT by retailers and suppliers.Keywords: Information and communication technology (ICT), internal relationship, inventory management, logistics services, supplier performance, supplier-retailer relationship.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 4009139 Robust Design and Optimization of Production Wastes: An Application for Industries
Authors: Christopher C. Ihueze, Charles C. Okpala, Christian E. Okafor, Peter O. Ogbobe
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This paper focuses on robust design and optimization of industrial production wastes. Past literatures were reviewed to case study Clamason Industries Limited (CIL) - a leading ladder-tops manufacturer. A painstaking study of the firm-s practices at the shop floor revealed that Over-production, Waiting time, Excess inventory, and Defects are the major wastes that are impeding their progress and profitability. Design expert8 software was used to apply Taguchi robust design and response surface methodology in order to model, analyse and optimise the wastes cost in CIL. Waiting time and overproduction rank first and second in contributing to the costs of wastes in CIL. For minimal wastes cost the control factors of overproduction, waiting-time, defects and excess-inventory must be set at 0.30, 390.70, 4 and 55.70 respectively for CIL. The optimal value of cost of wastes for the months studied was 22.3679. Finally, a recommendation was made that for the company to enhance their profitability and customer satisfaction, they must adopt the Shingeo Shingo-s Single Minute Exchange of Dies (SMED), which will immediately tackle the waste of waiting by drastically reducing their setup time.Keywords: Excess-inventory, setup time, single minute exchange of dies, optimal value, over-production, robust design.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1715138 Demand and Supply Chain Simulation in Telecommunication Industry by Multi-Rate Expert Systems
Authors: Andrus Pedai, Igor Astrov
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In modern telecommunications industry, demand & supply chain management (DSCM) needs reliable design and versatile tools to control the material flow. The objective for efficient DSCM is reducing inventory, lead times and related costs in order to assure reliable and on-time deliveries from manufacturing units towards customers. In this paper the multi-rate expert system based methodology for developing simulation tools that would enable optimal DSCM for multi region, high volume and high complexity manufacturing environment was proposed.Keywords: Demand & supply chain management, expert systems, inventory control, multi-rate control, performance metrics.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1891137 Psychometric Examination of the QUEST-25: An Online Assessment of Intellectual Curiosity and Scientific Epistemology
Authors: Matthew J. Zagumny
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The current study reports an examination of the QUEST-25 (Q-Assessment of Undergraduate Epistemology and Scientific Thinking) online version for assessing the dispositional attitudes toward scientific thinking and intellectual curiosity among undergraduate students. The QUEST-25 consists of scientific thinking (SIQ-25) and intellectual curiosity (ICIQ-25), which were correlated in hypothesized directions with the Religious Commitment Inventory, Curiosity and Exploration Inventory, Belief in Science scale, and measures of academic self-efficacy. Additionally, concurrent validity was established by the resulting significant differences between those identifying the centrality of religious belief in their lives and those who do not self-identify as being guided daily by religious beliefs. This study demonstrates the utility of the QUEST-25 for research, evaluation, and theory development.
Keywords: Guided-inquiry learning, intellectual curiosity, psychometric assessment, scientific thinking.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 760136 Study on the Relations between One's Personality Dimensions and his Personality Judgment about Friend based on Reality Distortion
Authors: Bahareh Babaei, Hadi Bahrami Ehsan, Reza Reza-zadeh, Hossien Kaviani
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Judgment is affected by many agents and distortion in this assessment is unpreventable. Personality dimensions are among those factors that interfere with the distortion. In this research, the relations between personality dimensions of subject and his judgment on friends- personality dimensions is investigated. One-hundred friend couples completed both NEO Five Factor Inventory (NEOFFI) and Ahvaz Reality Distortion Inventory (ARDI) to make judgments about themselves and their friends. Observations show that judge-s Agreement and Neuroticism dimensions are impressed by reality distortion. On the other hand, this reality distortion interferes with one-s evaluation of his friend-s Agreement, Neuroticism, and Conscientiousness dimensions. Conscientiousness with suppressive effect on judge-s other dimensions plays the irrelevant role on personality judgment. Therefore, observer-rating tools which are used as a conventional criterion seem to be not valid because of the reality distortion due to judge-s personality dimensions.
Keywords: Personality dimensions, reality distortion, judgmental accuracy.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1516135 Sampling of Variables in Discrete-Event Simulation using the Example of Inventory Evolutions in Job-Shop-Systems Based on Deterministic and Non-Deterministic Data
Authors: Bernd Scholz-Reiter, Christian Toonen, Jan Topi Tervo, Dennis Lappe
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Time series analysis often requires data that represents the evolution of an observed variable in equidistant time steps. In order to collect this data sampling is applied. While continuous signals may be sampled, analyzed and reconstructed applying Shannon-s sampling theorem, time-discrete signals have to be dealt with differently. In this article we consider the discrete-event simulation (DES) of job-shop-systems and study the effects of different sampling rates on data quality regarding completeness and accuracy of reconstructed inventory evolutions. At this we discuss deterministic as well as non-deterministic behavior of system variables. Error curves are deployed to illustrate and discuss the sampling rate-s impact and to derive recommendations for its wellfounded choice.Keywords: discrete-event simulation, job-shop-system, sampling rate.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1828134 Relationship between Level of Physical Activity and Exercise Imagery among Klang Valley Citizens
Authors: Kok, M.O., Omar-Fauzee, M.S., Rosli, M.H.
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This study investigated the relationship between exercise imagery use and level of physical activity within a wide range of exercisers in Klang valley, Malaysia. One hundred and twenty four respondents (Mage = 28.92, SD = 9.34) completed two sets of questionnaires (Exercise Imagery Inventory and Leisure-Time Exercise Questionnaire) that measure the use of imagery and exercise frequency of participants. From the result obtained, exercise imagery is found to be significantly correlated to level of physical activity. Besides that, variables such as gender, age and ethnicity that may affect the use of imagery and exercise frequency were also being assessed in this study. Among all variables, only ethnicity showed significant difference in level of physical activity (p < 0.05). Findings in this study suggest that further investigation should be done on other variables such as socioeconomic, educational level, and selfefficacy that may affect the imagery use and frequency of physical activity among exercisers.Keywords: Physical activity, exercise imagery, ExerciseImagery Inventory, Leisure-Time Exercise Questionnaire
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2447133 Predictors of Academic Achievement of Student ICT Teachers with Different Learning Styles
Authors: Deniz Deryakulu, Şener Büyüköztürk Hüseyin Özçınar
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The main purpose of this study was to determine the predictors of academic achievement of student Information and Communications Technologies (ICT) teachers with different learning styles. Participants were 148 student ICT teachers from Ankara University. Participants were asked to fill out a personal information sheet, the Turkish version of Kolb-s Learning Style Inventory, Weinstein-s Learning and Study Strategies Inventory, Schommer's Epistemological Beliefs Questionnaire, and Eysenck-s Personality Questionnaire. Stepwise regression analyses showed that the statistically significant predictors of the academic achievement of the accommodators were attitudes and high school GPAs; of the divergers was anxiety; of the convergers were gender, epistemological beliefs, and motivation; and of the assimilators were gender, personality, and test strategies. Implications for ICT teaching-learning processes and teacher education are discussed.
Keywords: Academic achievement, student ICT teachers, Kolb learning styles, experiential learning.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2609132 Measuring Principal and Teacher Cultural Competency: A Needs Assessment of Three Proximate PreK-5 Schools
Authors: Teresa Caswell
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Throughout the United States and within a myriad of demographic contexts, students of color experience the results of systemic inequities as an academic outcome. These disparities continue despite the increased resources provided to students and ongoing instruction-focused professional learning received by teachers. We postulated that lower levels of educator cultural competency are an underlying factor of why resource and instructional interventions are less effective than desired. Before implementing any type of intervention, however, cultural competency needed to be confirmed as a factor in schools demonstrating academic disparities between racial subgroups. A needs assessment was designed to measure levels of individual beliefs, including cultural competency, in both principals and teachers at three neighboring schools verified to have academic disparities. The resulting mixed method study utilized the Optimal Theory Applied to Identity Development (OTAID) model to measure cultural competency quantitatively, through self-identity inventory survey items, with teachers and qualitatively, through one-on-one interviews, with each school’s principal. A joint display was utilized to see combined data within and across school contexts. Each school was confirmed to have misalignments between principal and teacher levels of cultural competency beliefs while also indicating that a number of participants in the self-identity inventory survey may have intentionally skipped items referencing the term oppression. Additional use of the OTAID model and self-identity inventory in future research and across contexts is needed to determine transferability and dependability as cultural competency measures.
Keywords: Cultural competency, identity development, mixed method analysis, needs assessment.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 177131 Simulation of Agri-Food Supply Chains
Authors: Sherine Beshara, Khaled S. El-Kilany, Noha M. Galal
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Supply chain management has become more challenging with the emerging trend of globalization and sustainability. Lately, research related to perishable products supply chains, in particular agricultural food products, has emerged. This is attributed to the additional complexity of managing this type of supply chains with the recently increased concern of public health, food quality, food safety, demand and price variability, and the limited lifetime of these products. Inventory management for agrifood supply chains is of vital importance due to the product perishability and customers- strive for quality. This paper concentrates on developing a simulation model of a real life case study of a two echelon production-distribution system for agri-food products. The objective is to improve a set of performance measures by developing a simulation model that helps in evaluating and analysing the performance of these supply chains. Simulation results showed that it can help in improving overall system performance.Keywords: Agri-food supply chains, inventory model, modelling and Simulation, supply chain.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3362130 A Novel Model for Simultaneously Minimising Costs and Risks in Just-in-Time Systems Using Multi-Backup Suppliers: Part 1- Modelling
Authors: Faraj El Dabee, Romeo Marian, Yousef Amer
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Just-In-Time (JIT) is a lean manufacturing tool, which provides the benefits of efficiency, and of minimizing unnecessary costs for many organisations. However, the risks arising from these benefits have been disregarded. These risks impact on system processes disrupting the whole supply chain. This paper proposes an inventory model that can simultaneously reduce costs and risks in JIT systems. This model is developed to ascertain an optimal ordering strategy for procuring raw materials by using regular multi-external and local backup suppliers to reduce the total cost of the products, and at the same time to reduce the risks arising from this cost reduction within production systems. Some results that will be illustrated in the second part of this paper are presented.
Keywords: Lean manufacturing, Just-in-Time (JIT), production system, cost-risk reduction, inventory model, eternal supplier, local backup supplier.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1654129 Deep Reinforcement Learning for Optimal Decision-making in Supply Chains
Authors: Nitin Singh, Meng Ling, Talha Ahmed, Tianxia Zhao, Reinier van de Pol
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We propose the use of Reinforcement Learning (RL) as a viable alternative for optimizing supply chain management, particularly in scenarios with stochasticity in product demands. RL’s adaptability to changing conditions and its demonstrated success in diverse fields of sequential decision-making make it a promising candidate for addressing supply chain problems. We investigate the impact of demand fluctuations in a multi-product supply chain system and develop RL agents with learned generalizable policies. We provide experimentation details for training RL agents and a statistical analysis of the results. We study generalization ability of RL agents for different demand uncertainty scenarios and observe superior performance compared to the agents trained with fixed demand curves. The proposed methodology has the potential to lead to cost reduction and increased profit for companies dealing with frequent inventory movement between supply and demand nodes.
Keywords: Inventory Management, Reinforcement Learning, Supply Chain Optimization, Uncertainty.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 384128 A Modelling Study of the Photochemical and Particulate Pollution Characteristics above a Typical Southeast Mediterranean Urban Area
Authors: Kiriaki-Maria Fameli, Vasiliki D. Assimakopoulos, Vasiliki Kotroni
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The Greater Athens Area (GAA) faces photochemical and particulate pollution episodes as a result of the combined effects of local pollutant emissions, regional pollution transport, synoptic circulation and topographic characteristics. The area has undergone significant changes since the Athens 2004 Olympic Games because of large scale infrastructure works that lead to the shift of population to areas previously characterized as rural, the increase of the traffic fleet and the operation of highways. However, few recent modelling studies have been performed due to the lack of an accurate, updated emission inventory. The photochemical modelling system MM5/CAMx was applied in order to study the photochemical and particulate pollution characteristics above the GAA for two distinct ten-day periods in the summer of 2006 and 2010, where air pollution episodes occurred. A new updated emission inventory was used based on official data. Comparison of modeled results with measurements revealed the importance and accuracy of the new Athens emission inventory as compared to previous modeling studies. The model managed to reproduce the local meteorological conditions, the daily ozone and particulates fluctuations at different locations across the GAA. Higher ozone levels were found at suburban and rural areas as well as over the sea at the south of the basin. Concerning PM10, high concentrations were computed at the city centre and the southeastern suburbs in agreement with measured data. Source apportionment analysis showed that different sources contribute to the ozone levels, the local sources (traffic, port activities) affecting its formation.Keywords: Photochemical modelling, urban pollution, greater Athens area, MM5/CAMx.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1367127 Model Development for Allocation of Raw Material in Timber Processing Industry in Indonesia
Authors: Muh. Hisjam, Nancy Oktyajati, Wakhid A. Jauhari, Wahyudi Sutopo
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This research is intended to develop a raw material allocation model in timber processing industry in Perum Perhutani Unit I, Central Java, Indonesia. The model can be used to determine the quantity of allocation of timber between chain in the supply chain to select supplier considering factors that are log price and the distance. In determining the quantity of allocation of timber between chains in the supply chain, the model considers the optimal inventory in each chain. Whilst the optimal inventory is determined based on demand forecast, the capacity and safety stock. Problem solving allocation is conducted by developing linear programming model that aims to minimize the total cost of the purchase, transportation cost and storage costs at each chain. The results of numerical examples show that the proposed model can generate savings of the purchase cost of 20.84% and select suppliers with mileage closer.
Keywords: Allocation model, linear programming, purchase costs, storage costs, suppliers, transportation costs.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1487126 Fuzzy EOQ Models for Deteriorating Items with Stock Dependent Demand and Non-Linear Holding Costs
Authors: G. C. Mahata, A. Goswami
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This paper deals with infinite time horizon fuzzy Economic Order Quantity (EOQ) models for deteriorating items with stock dependent demand rate and nonlinear holding costs by taking deterioration rate θ0 as a triangular fuzzy number (θ0 −δ 1, θ0, θ0 +δ 2), where 1 2 0 0 <δ ,δ <θ are fixed real numbers. The traditional parameters such as unit cost and ordering cost have been kept constant but holding cost is considered to vary. Two possibilities of variations in the holding cost function namely, a non-linear function of the length of time for which the item is held in stock and a non-linear function of the amount of on-hand inventory have been used in the models. The approximate optimal solution for the fuzzy cost functions in both these cases have been obtained and the effect of non-linearity in holding costs is studied with the help of a numerical example.
Keywords: Inventory Model, Deterioration, Holding Cost, Fuzzy Total Cost, Extension Principle.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1814125 Extraction of Forest Plantation Resources in Selected Forest of San Manuel, Pangasinan, Philippines Using LiDAR Data for Forest Status Assessment
Authors: Mark Joseph Quinto, Roan Beronilla, Guiller Damian, Eliza Camaso, Ronaldo Alberto
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Forest inventories are essential to assess the composition, structure and distribution of forest vegetation that can be used as baseline information for management decisions. Classical forest inventory is labor intensive and time-consuming and sometimes even dangerous. The use of Light Detection and Ranging (LiDAR) in forest inventory would improve and overcome these restrictions. This study was conducted to determine the possibility of using LiDAR derived data in extracting high accuracy forest biophysical parameters and as a non-destructive method for forest status analysis of San Manual, Pangasinan. Forest resources extraction was carried out using LAS tools, GIS, Envi and .bat scripts with the available LiDAR data. The process includes the generation of derivatives such as Digital Terrain Model (DTM), Canopy Height Model (CHM) and Canopy Cover Model (CCM) in .bat scripts followed by the generation of 17 composite bands to be used in the extraction of forest classification covers using ENVI 4.8 and GIS software. The Diameter in Breast Height (DBH), Above Ground Biomass (AGB) and Carbon Stock (CS) were estimated for each classified forest cover and Tree Count Extraction was carried out using GIS. Subsequently, field validation was conducted for accuracy assessment. Results showed that the forest of San Manuel has 73% Forest Cover, which is relatively much higher as compared to the 10% canopy cover requirement. On the extracted canopy height, 80% of the tree’s height ranges from 12 m to 17 m. CS of the three forest covers based on the AGB were: 20819.59 kg/20x20 m for closed broadleaf, 8609.82 kg/20x20 m for broadleaf plantation and 15545.57 kg/20x20m for open broadleaf. Average tree counts for the tree forest plantation was 413 trees/ha. As such, the forest of San Manuel has high percent forest cover and high CS.
Keywords: Carbon stock, forest inventory, LiDAR, tree count.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1281124 Impact of ISO 9000 on Time-based Performance: An Event Study
Authors: Chris K. Y. Lo, Andy C. L. Yeung, T. C. Edwin Cheng
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ISO 9000 is the most popular and widely adopted meta-standard for quality and operational improvements. However, only limited empirical research has been conducted to examine the impact of ISO 9000 on operational performance based on objective and longitudinal data. To reveal any causal relationship between the adoption of ISO 9000 and operational performance, we examined the timing and magnitude of change in time-based performance as a result of ISO 9000 adoption. We analyzed the changes in operating cycle, inventory days, and account receivable days prior and after the implementation of ISO 9000 in 695 publicly listed manufacturing firms. We found that ISO 9000 certified firms shortened their operating cycle time by 5.28 days one year after the implementation of ISO 9000. In the long-run (3 years after certification), certified firms showed continuous improvement in time-based efficiency, and experienced a shorter operating cycle time of 11 days than that of non-certified firms. There was an average of 6.5% improvement in operating cycle time for ISO 9000 certified firms. Both inventory days and account receivable days showed similar significant improvements after the implementation of ISO 9000, too.
Keywords: ISO 9000, Operating Cycle, Time-based efficiency.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2074123 An Optimal Algorithm for Finding (r, Q) Policy in a Price-Dependent Order Quantity Inventory System with Soft Budget Constraint
Authors: S. Hamid Mirmohammadi, Shahrazad Tamjidzad
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This paper is concerned with the single-item continuous review inventory system in which demand is stochastic and discrete. The budget consumed for purchasing the ordered items is not restricted but it incurs extra cost when exceeding specific value. The unit purchasing price depends on the quantity ordered under the all-units discounts cost structure. In many actual systems, the budget as a resource which is occupied by the purchased items is limited and the system is able to confront the resource shortage by charging more costs. Thus, considering the resource shortage costs as a part of system costs, especially when the amount of resource occupied by the purchased item is influenced by quantity discounts, is well motivated by practical concerns. In this paper, an optimization problem is formulated for finding the optimal (r, Q) policy, when the system is influenced by the budget limitation and a discount pricing simultaneously. Properties of the cost function are investigated and then an algorithm based on a one-dimensional search procedure is proposed for finding an optimal (r, Q) policy which minimizes the expected system costs.Keywords: (r, Q) policy, Stochastic demand, backorders, limited resource, quantity discounts.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1864122 Differential Analysis: Crew Resource Management and Profiles on the Balanced Inventory of Desirable Responding
Authors: Charalambos C. Cleanthous, Ryan Sain, Tabitha Black, Stephen Vera, Suzanne Milton
Abstract:
A concern when administering questionnaires is whether the participant is providing information that is accurate. The results may be invalid because the person is trying to present oneself in an unrealistic positive manner referred to as ‘faking good’, or in an unrealistic negative manner known as ‘faking bad’. The Balanced Inventory of Desirable Responding (BIDR) was used to assess commercial pilots’ responses on the two subscales of the BIDR: impression management (IM) and self-deceptive enhancement (SDE) that result in high or low scores. Thus, the BIDR produces four valid profiles: IM low and SDE low, IM high and SDE low, IM low and SDE high, and IM high and SDE high. The various profiles were used to compare the respondents’ answers to crew resource management (CRM) items developed from the USA Federal Aviation Administration’s (FAA) guidelines for CRM composition and training. Of particular interest were the results on the IM subscale. The comparisons between those scoring high (lying or faking) versus those low on the IM suggest that there were significant differences regarding their views of the various dimensions of CRM. One of the more disconcerting conclusions is that the high IM scores suggest that the pilots were trying to impress rather than honestly answer the questions regarding their CRM training and practice.
Keywords: USA commercial pilots, crew resource management, faking, social desirability.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 935121 Emotional Intelligence and Leadership Profiles among Students’ Representative Council of Malaysian Public Universities
Authors: R. A. Harun, N. M. Ishak, N. Yusoff, S. Amat
Abstract:
This quantitative research is aimed to identify the level of leadership quality and emotional intelligence for members of Students' Representatives Council (SRC) of Malaysian Public Universities (MPU). The variables include the leadership quality and emotional quotient (EQ). 238 SRC members in MPU were selected as subjects of the study. Data were collected using two instruments i.e. Malaysian Emotional Quotient Inventory (MEQI) and Ayu-Noriah Leadership Audit Trail Inventory (Ayu-Noriah, LATI). Data were analyzed using descriptive (mean and percentage). Research findings showed that the subjects scored highly in four out of five EQ domains (Self-Regulations, Self-Motivation, Empathy and Social Skills). However, the subjects scored medium to low in Self-Awareness. Analysis on the sub domains (a total of 28 sub domains) showed that the subjects scored high in 17 sub domains for EQ, whilst another 11 were at medium level. The overall analysis indicates that the subjects have high level of EQ. Findings on their leadership qualities showed that they obtained high scores in all seven factors that were measured i.e. Strategy and Leadership Model, Recruit, Review Performance and Honor, Deploy Strategically, Developing, Engage and Retain and Built HR Capabilities/Line Ownership. The overall score for leadership qualities was found to be high.
Keywords: Emotional intelligence, leadership, students.
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