New Zealand's success in raising agricultural productivity has been accompanied by higher input use, leading to adverse effects on the environment. Until recently, analysis of farm performance has tended to ignore...
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New Zealand's success in raising agricultural productivity has been accompanied by higher input use, leading to adverse effects on the environment. Until recently, analysis of farm performance has tended to ignore such negative externalities. The current emphasis on environmental issues has led dairy farmers to target improvements in both environmental performance and productivity. Therefore, measuring the environmental performance of farms and integrating this information into farm productivity calculations should assist in making informed policy decisions which promote sustainable development. However, this is a challenging process since conventional environmental efficiency measures are usually based on simple input and output flows but nitrogen discharge is a complex process affected by climate, pasture composition, cow physiology and geophysical variability. Furthermore, the outdoor pastoral nature of New Zealand farming means that it is difficult to control input and output flows, particularly of nitrogen. We present a novel approach to measure the environmental and economic efficiency of farms, using the Overseer nutrient budget model and spatially micro-simulated virtual population data. The empirical analysis is based on dairy farms in the Karapiro catchment, where nitrogen discharge from dairy farming is a major source of nonpoint pollution. (c) 2010 IMACS. Published by Elsevier B.V. All rights reserved.
Summary form only given. Decision making is a complex job, especially when it involves millions of dollars. Experience, intuition and other personal features are essential, but the support of a mathematical tool can h...
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ISBN:
(纸本)9781424413065
Summary form only given. Decision making is a complex job, especially when it involves millions of dollars. Experience, intuition and other personal features are essential, but the support of a mathematical tool can help avoiding errors. This paper presents a summary of the experience acquired by the Petrobras refinery simulation team in using mathematical models to support investment decisions in tank farm problems. Real situations will be presented where limitations and risks came up along with recommendations to avoid similar problems in the future.
An overview is presented of SAS simulation Studio, an object-oriented, Java-based application for building and analyzing discrete-event simulation models. Emphasis is given to simulation Studio's hierarchical, ent...
ISBN:
(纸本)9781479920778
An overview is presented of SAS simulation Studio, an object-oriented, Java-based application for building and analyzing discrete-event simulation models. Emphasis is given to simulation Studio's hierarchical, entity-based approach to resource modeling, which facilitates the creation of realistic simulation models for systems with complicated resource requirements, such as preemption. Also discussed are the various ways that simulation Studio integrates with SAS and JMP for data management, distribution fitting, and experimental design.
The complexity of simulation models has increased during the last years in semiconductor foundries. Manual and automated decisions have to be modeled in detail to make the right conclusions from them. We describe an a...
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ISBN:
(纸本)9781509044849
The complexity of simulation models has increased during the last years in semiconductor foundries. Manual and automated decisions have to be modeled in detail to make the right conclusions from them. We describe an approach that uses forward simulation to minimize modeling effort and mimics fab behavior to a high degree. The approach is applied to the problem of controlling time link chains. Results are presented and other applications are discussed.
The design of a supply chain network as an integrated system with several tiers of suppliers is a difficult task. It consists of making strategic decisions on the facility location, stocking location, production polic...
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The design of a supply chain network as an integrated system with several tiers of suppliers is a difficult task. It consists of making strategic decisions on the facility location, stocking location, production policy, production capacity, distribution and transportation modes. This research develops a hybrid optimization approach to address the supply chain configuration design problem. The new approach combines simulation, mixed integer programming and genetic algorithm. The genetic algorithm provides a mechanism to optimize qualitative and policy variables. The mixed integer programming model reduces computing efforts by manipulating quantitative variables. Finally simulation is used to evaluate performance of each supply chain configuration with nonlinear, complex relationships and under more realistic assumptions. The approach is designed to be robust and could handle the large scale of the real world problems.
In this paper we present the use of "what-if"-analysis in simulation games for spatial decision making by introducing the concept of multiple worlds. We expect that "what-if"-analysis in games enab...
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ISBN:
(纸本)9781424427086
In this paper we present the use of "what-if"-analysis in simulation games for spatial decision making by introducing the concept of multiple worlds. We expect that "what-if"-analysis in games enables the trainees to achieve more robust results, which is defined as the ability to achieve the required goals given different scenarios. Scenarios are defined as exogenous variables on the multiple-worlds. Viable decisions for a particular world are assessed by splitting the given world into multiple ones and running simulations for these new worlds. This assessment is performed by a) comparing the alternatives represented by each world and b) exploring the timeline of each world by selecting specific time instants. The navigation both through multiple worlds and through time should provide the users the possibility to formulate a robust answer for the specified problem. We will present a viable architecture and 4 distinct modes of game-play for the simulation game.
This book reports on the latest advances in understanding cross-cultural decision and human cognition with respect to various cultural constructs, such as geographical, historical, sociological, and organization...
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ISBN:
(数字)9783319607474
ISBN:
(纸本)9783319607467
This book reports on the latest advances in understanding cross-cultural decision and human cognition with respect to various cultural constructs, such as geographical, historical, sociological, and organizational cultures. It addresses researchers, scholars, and industry practitioners from diverse fields, including sociology, linguistics, business, military science, psychology, human factors research, neuroscience, and education. The book covers a wealth of topics, including: analyses of historical events and intercultural competence; commercial applications of social-cultural science; the study of decision-making similarities (and differences) across cultures; cultural behavioral modeling and simulation technology; and social networks and studies on group communication alike. It also reports on real-world case studies relevant to cross-cultural decision-making. The book’s main goal is to combine studies from other relevant disciplines such as causal analysis in complex environments, team decision making and social changes to develop a more holistic understanding of the decisions that people, groups, and societies make, so as to improve our ability to forecast and plan for the future. Based on the AHFE 2017 International conference on Cross-Cultural Decision making (CCDM), held on July 17–21, 2017, in Los Angeles, California, USA, this book offers a multidisciplinary view on the impact of culture on people’s cognition and behavior, and a timely reference guide to new applications and future challenges.
The paper introduces a new constraint-based graphical approach to modeling construction processes, Foresight, designed to combine the versatility of discrete-event simulation, the ease-of-use of the Critical Path Meth...
ISBN:
(纸本)9781479920778
The paper introduces a new constraint-based graphical approach to modeling construction processes, Foresight, designed to combine the versatility of discrete-event simulation, the ease-of-use of the Critical Path Method, and the visual insight of linear scheduling. The usability of Foresight is compared with Stroboscope (a construction-specific simulation system) in a case study of the classic earthmoving problem. The Foresight model is shown, first, to be visually more insightful than its Stroboscope equivalent, and second, to require a fraction of the number of modeling terms and modeling concepts in its definition.
Decision making in industry continues to become more complicated. Customers are more demanding, competition is more fierce, and costs for labor and raw materials continue to rise. Managers need state-of-the-art tools ...
ISBN:
(纸本)9781479920778
Decision making in industry continues to become more complicated. Customers are more demanding, competition is more fierce, and costs for labor and raw materials continue to rise. Managers need state-of-the-art tools to help in planning, design, and operations of their facilities. simulation provides a virtual factory where ideas can be tested and performance improved. The AutoMod product suite from Applied Materials has been used on thousands of projects to help engineers and managers make the best decisions possible. AutoMod supports hierarchical model construction. This architecture allows users to reuse model components in other models, decreasing the time required to build a model. In addition, recent enhancements to AutoMod's material handling template systems have in-creased modeling accuracy and ease-of-use. These latest advances have helped make AutoMod one of the most widely used simulation software packages.
This paper investigates two related questions: (1) How to derive a confidence interval for the output of a combination of simulation inputs not yet simulated? (2) How to select the next combination to be simulated whe...
ISBN:
(纸本)9781479920778
This paper investigates two related questions: (1) How to derive a confidence interval for the output of a combination of simulation inputs not yet simulated? (2) How to select the next combination to be simulated when searching for the optimal combination? To answer these questions, the paper uses parametric bootstrapped Kriging and "conditional simulation", whereas classic Kriging estimates the variance of its predictor by plugging-in the estimated GP parameters so this variance is biased. The main conclusion is that classic Kriging seems quite robust; i.e., classic Kriging gives acceptable confidence intervals and estimates of the optimal solution.
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