Discrete Time Analysis of Consolidated Transport Processes


Book Description

The objective of this work is to develop models for the analysis of consolidated transport processes. With the discrete time queuing models developed for inventory and vehicle consolidation, in particular milkrun systems, a detailed performance evaluation of different design scenarios can be conducted faster than with simulation. Moreover, it is demonstrated how the models can be connected with each other in form of a network analysis, in order to analyze hub-and-spoke networks.




Performance evaluation of shuttle-based storage and retrieval systems using discrete-time queueing network models


Book Description

Shuttle-based storage and retrieval systems (SBS/RSs) are an important part of today's warehouses. In this work, a new approach is developed that can be applied to model different configurations of SBS/RSs. The approach is based on the modeling of SBS/RSs as discrete-time open queueing networks and yields the complete probability distributions of the performance measures.







Performance analysis of stochastic flow lines with limited material supply


Book Description

In order to improve the performance of production systems, companies consider the optimization of the flow line configuration. However, the material supply of the flow line exerts a strong influence on the output of the production system since material shortages impede the flow of workpieces through the flow line. Simultaneously, the configuration of the flow line determines the demand for material. Consequently, the mutual interdependence between the material supply and the flow line has to be considered in order to balance a sufficient material supply of the flow line avoiding material shortages as well as excessive material inventory and handling effort. We provide integrated approaches for the evaluation and optimization of stochastic flow lines with limited material supply. Thereby, we make use of several evaluation methods as Markov chain approaches, aggregation and decomposition approaches as well as linear programming. Further, we model open and closed queuing networks in continuous and discrete time. Hence, we present exact and approximate approaches that allow us to study the effects in several stochastic production systems with limited material supply.




Subsurface Solute Transport Models and Case Histories


Book Description

The book addresses the development of the basic knowledge of the subsurface solute transfer with a particular emphasis on field data collection and analysis coupled with modeling (analytical and numerical) tool application. The relevant theoretical developments are concerned mainly with the formulation and solution of deterministic mass-transport equations for a wide range of engineering issues in groundwater quality assessment and forecasting. The book gives many computational examples and case studies drawn from the conducted field investigations. The analyzed problems are as follows: investigation and prediction of groundwater contamination by industrial contaminants and solutions (radionuclides, chloride and nitrate brine) with special focus on the effect of (a) aquifer heterogeneity, anisotropy, and dual porosity, (b) density contrast existing between industrial waste and groundwater, or in density-stratified artesian and coastal groundwater systems; (c) physicochemical interactions that play a major role in retarding (e.g. adsorption) or enhancing (e.g. interactions between dissolved species and mobile colloids) contaminant transport; prediction of the effects of pumping on groundwater quality at wellfields; groundwater dating using stable and radioactive isotopes for prediction and assessment of contamination potential; field and laboratory tests’ design and analysis, and monitoring data interpretation; partitioning of surface and subsurface flows using isotope techniques. One of the most essential topics addressed in the book is the migration and fate of radionuclides. Model development is motivated by field data analysis from a number of radioactively contaminated sites in the Russian Federation: near-surface radioactive waste disposal sites and deep-well radioactive waste injection sites. They play a unique role in the advancement of knowledge of the subsurface behavior and fate of many hazardous radionuclides and can be considered as field-scale laboratories. Thus, the book, along with theoretical findings, contains field information, which will facilitate the understanding of subsurface solute transport and the development of a methodology for practical applications to groundwater hydrology.







Innovations for Community Services


Book Description

This book constitutes the refereed proceedings of the 18th International Conference on Innovations for Community Services, I4CS 2018, held in Žilina, Slovakia, in June 2018. The 14 revised full papers and the three revised short papers presented in this volume were carefully reviewed and selected from 38 submissions. The papers are organized in topical sections on architectures and management; data analytics and models; community and public collaboration; innovations and digital transformation.




Carbon Dioxide Sequestration in Geological Media


Book Description

Over the past 20 years, the concept of storing or permanently storing carbon dioxide in geological media has gained increasing attention as part of the important technology option of carbon capture and storage within a portfolio of options aimed at reducing anthropogenic emissions of greenhouse gases to the earths atmosphere. This book is structured into eight parts, and, among other topics, provides an overview of the current status and challenges of the science, regional assessment studies of carbon dioxide geological sequestration potential, and a discussion of the economics and regulatory aspects of carbon dioxide sequestration.