21 research outputs found

    Exploring congestion impact beyond the bulk cargo terminal gate

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    Bulk cargo terminal congestion management, approaches have tended to bealmost exclusively focused on the sea side of bulk terminals. To-date there hasbeen very limited work on land-side approaches to mitigate congestion in bulkterminals. This research aims to address these gaps by considering the effectivenessof multiple congestion management methods across a range of throughputscenarios. This paper develops a discrete event simulation model based on datacollected from an Australian bulk wood chip export maritime terminal and analysesthe effect of infrastructure and process improvements on gate congestionand hinterland logistics chains. The improvements include: variations of terminalconfigurations, a terminal appointment system and gate automation technology.This paper argues that traditional efficiency and utilization measures fail to capturethe impact of these alternatives over the whole hinterland logistics chain.Results indicate that the gate automation technology and the introduction ofan appointment system can reduce average turnaround times by approximately20%. Interestingly additional unloading capacity has a relatively small influence(<10%) on the average turnaround time under the initial truck arrival frequency.Significantly, findings highlight how the range of alternatives that improve efficiencyand utilization can be impaired when organizations do not plan andnegotiate impacts with other terminal users along the hinterland logistics chain.The impact of these alternatives needs to be evaluated in the broader hinterlandperspective to enhance stakeholder ’buy-in’ and resilience over time of solutionsimplemented

    Dynamics in Logistics

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    This open access book highlights the interdisciplinary aspects of logistics research. Featuring empirical, methodological, and practice-oriented articles, it addresses the modelling, planning, optimization and control of processes. Chiefly focusing on supply chains, logistics networks, production systems, and systems and facilities for material flows, the respective contributions combine research on classical supply chain management, digitalized business processes, production engineering, electrical engineering, computer science and mathematical optimization. To celebrate 25 years of interdisciplinary and collaborative research conducted at the Bremen Research Cluster for Dynamics in Logistics (LogDynamics), in this book hand-picked experts currently or formerly affiliated with the Cluster provide retrospectives, present cutting-edge research, and outline future research directions

    A Decision Support System for Intermodal Logistics under Considerations for Costs of Security

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    Global supply chains have been challenged by the increased awareness of security risks, including those of terrorism, theft, and damage, and the potential in these risks for significant damages. Additionally, the pressure security initiatives and regulations, particularly at sea and air ports, threaten to add to congestion at these hubs in the international flow of goods and materials. Improving the efficiency of the flow of goods and materials, and therefore the stability and competitiveness of their supply chains, is the focus of this research. A decision support to combine strategic objectives with operational transport decision making is built to incorporate security considerations

    Optimizing Vehicle Replacement in Sustainable Urban Freight Transportation Subject to Presence of Regulatory Measures

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    Publisher Copyright: © 2023 by the authors.Since the 1990s, studies and pilot tests have been conducted to reduce traffic, accidents, and pollution due to urban freight transport (UFT). These ended up in several policies, regulations, and restrictions for UFT, such as low emission zones, delivery time windows, and vehicle size and weight restrictions. However, issues in UFT under regulatory measures still persist. This study introduces an optimization framework for deriving an optimal combination of various types of vehicles with different capacities for vehicle replacement with UFT. This framework allows an understanding of how an urban freight company with a limited budget efficiently satisfies its freight demand within an urban area in the presence of regulatory measures by urban administrators. The introduced formulation, which is mixed-integer linear programming, will assist the operator in choosing the best investment strategy for introducing new vehicles of certain types and sizes, for operation in different zones, into its fleet while gaining economic benefits and having a positive impact on the liveability of the urban area. Furthermore, an elasticity analysis is performed to consider the effects of specific uncertain parameters on the total cost. The numerical results show that the share of electric vehicles in the fleet increases, and they are more competitive than diesel vehicles.publishersversionpublishe

    Dynamics in Logistics

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    This open access book highlights the interdisciplinary aspects of logistics research. Featuring empirical, methodological, and practice-oriented articles, it addresses the modelling, planning, optimization and control of processes. Chiefly focusing on supply chains, logistics networks, production systems, and systems and facilities for material flows, the respective contributions combine research on classical supply chain management, digitalized business processes, production engineering, electrical engineering, computer science and mathematical optimization. To celebrate 25 years of interdisciplinary and collaborative research conducted at the Bremen Research Cluster for Dynamics in Logistics (LogDynamics), in this book hand-picked experts currently or formerly affiliated with the Cluster provide retrospectives, present cutting-edge research, and outline future research directions

    Supply chain risk management practice in Malaysian automotive industry

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    Organizations are experiencing increasing supply chain risks especially due to new business trends such as globalization and offshoring. For that reason, supply chain risk management is required to manage those risks effectively. Although there is a voluminous academic research on descriptive and conceptual model of supply chain risk management, evidences which describe the implementation of supply chain risk management in industry are limited. Therefore, the purpose of this research is to explore the implementation of supply chain risk management among Malaysian small and medium automotive companies. This study also explores the enablers to supply chain risk management implementation and barriers that impede this practice. Case study method was employed at three companies which were selected through purposeful sampling. By using thematic analysis, the data was analyzed and interpreted. The research results indicated that all three companies were heading towards more formal supply chain risk management implementation. Although the companies managed the supply chain risks based on TS16949 standard and company formal procedures, the tools used in the supply chain risk management, risk communication, training and risk responsibility were yet to be completely formalized. Pressure from customers and top management emerged as the primary enablers to such implementation. This study also revealed that barriers rooted from companies internal such as the lack of knowledge impeded the case companies from advancing their supply chain risk management implementation. The findings of this study offer a description of supply chain risk management implementation for organizations

    Modeling and Implementation of Wireless Sensor Networks for Logistics Applications

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    Logistics has experienced a long time of developments and improvements based on the advanced vehicle technologies, transportation systems, traffic network extension and logistics processes. In the last decades, the complexity has increased significantly and this has created complex logistics networks over multiple continents. Because of the close cooperation, these logistics networks are highly dependent on each other in sharing and processing the logistics information. Every customer has many suppliers and vice versa. The conventional centralized control continues but reaches some limitations such as the different distribution of suppliers, the complexity and flexibility of processing orders or the dynamics of the logistic objects. In order to overcome these disadvantages, the paradigm of autonomous logistics is proposed and promises a better technical solution for current logistics systems. In autonomous logistics, the decision making is shifted toward the logistic objects which are defined as material items (e.g., vehicles, containers) or immaterial items (e.g., customer orders) of a networked logistics system. These objects have the ability to interact with each other and make decisions according to their own objectives. In the technical aspect, with the rapid development of innovative sensor technology, namely Wireless Sensor Networks (WSNs), each element in the network can self-organize and interact with other elements for information transmission. The attachment of an electronic sensor element into a logistic object will create an autonomous environment in both the communication and the logistic domain. With this idea, the requirements of logistics can be fulfilled; for example, the monitoring data can be precise, comprehensive and timely. In addition, the goods flow management can be transferred to the information logistic object management, which is easier by the help of information technologies. However, in order to transmit information between these logistic objects, one requirement is that a routing protocol is necessary. The Opportunistic relative Distance-Enabled Uni-cast Routing (ODEUR ) protocol which is proposed and investigated in this thesis shows that it can be used in autonomous environments like autonomous logistics. Moreover, the support of mobility, multiple sinks and auto-connection in this protocol enhances the dynamics of logistic objects. With a general model which covers a range from low-level issues to high-level protocols, many services such as real time monitoring of environmental conditions, context-aware applications and localization make the logistic objects (embedded with sensor equipment) more advanced in information communication and data processing. The distributed management service in each sensor node allows the flexible configuration of logistic items at any time during the transportation. All of these integrated features introduce a new technical solution for smart logistic items and intelligent transportation systems. In parallel, a management system, WSN data Collection and Management System (WiSeCoMaSys), is designed to interact with the deployed Wireless Sensor Networks. This tool allows the user to easily manipulate the sensor networks remotely. With its rich set of features such as real time data monitoring, data analysis and visualization, per-node management, and alerts, this tool helps both developers and users in the design and deployment of a sensor network. In addition, an analytical model is developed for comparison with the results from simulations and experiments. Focusing on the use of probability theory to model the network links, this model considers several important factors such as packet reception rate and network traffic which are used in the simulation and experiment parts. Moreover, the comparison between simulation, experiment and analytical results is also carried out to estimate the accuracy of the design and make several improvements of the simulation accuracy. Finally, all of the above parts are integrated in one unique system. This system is verified by both simulations in logistic scenarios (e.g., harbors, warehouses and containers) and experiments. The results show that the proposed model and protocol have a good packet delivery rate, little memory requirements and low delay. Accordingly, this system design is practical and applicable in logistics

    Autonome Sensorsysteme in der Transport- und Lebensmittellogistik

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    A concise supervision of food products during transport is an essential precondition for the improvement of their quality and reduction of losses. However, existing remote or telemetric systems implement only parts of the entire supervision task. Standard systems measure temperature only at one or two points, and the evaluation of sensor data has to be done manually. This thesis presents a system which measures a spatial profile of temperature and other parameters. The idea of remote transport supervision is extended to a self-contained sensor system that locally processes measurement data and detects critical situations autonomously. The algorithms for sensor data evaluation are implemented inside the means of transport; they can either share a common embedded processor unit or run separately on wireless sensors nodes, which are attached to the loaded freight objects. The system automatically adapts the supervision process to different kinds of goods. This intelligent container combines technologies from different fields, such as RFID, wireless sensor networks, and telemetric system, which have so far been applied separately. A shelf life model, based on the dynamic temperature profile, estimates the amount of quality loss during transport. The quality supervision is implemented as a set of software agents. Each freight object is supervised by an individual sensory way bill . A demonstration system for the supervision of food transports shows the feasibility of this new approach

    Models and Methods for Multi-Actor Systems

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    2010/2011The study of the models and methods to apply to multi-actor systems is a widely discussed research topic in the related scientific literature. The multi-actor systems are defined as systems that are characterized by the presence of several autonomous elements, of different decision makers and of complex rules that allow the communication, the coordination and the connection of the components of such systems. Commonly, the study of Multi-Actor System, MAS, recalls the well-known issues concerning the multi-agent systems. The research topic related to the multi-agent system firstly started to appear in scientific literature in 1980s, mainly in relation to the computer science and artificial intelligence. In this dissertation, in particular, the study of the multi-agent systems, and specifically of the multi-actor systems, is taken into account merely in relation to the distinctive features of complexity that characterize such systems and not to the issues concerning the agent-oriented software engineering. Therefore, the research results presented in this thesis are focused on the development and on the realization of innovative models and methodologies to face the management and the decision making mechanisms applied to complex multi-actor systems. This dissertation especially focuses on two different examples of multi-actor systems in two very diverse perspectives. The former deals with the research problem related to intermodal transportation networks, while the latter with the so called consensus problem in distributed networks of agents. Concerning the research problem related to the intermodal logistic systems, the research activity addresses the management of their more and more increasing complexity by the applications of the modern Information and Communication Technologies (ICT) tools that are key solutions to achieve the efficiency and to enhance logistics competitiveness. The related scientific literature still seems lacking in addressing with adequate attention the impact of these new techniques on the management of these complex systems and, moreover, there is an apparent lack of a systematic and general methodology to describe in detail the multiplicity of elements that can influence the dynamics and the corresponding information and decision making structure of intermodal transportation systems. The innovative results presented in this dissertation are focused on the development of an Integrated System, IS, devoted to manage intermodal transportation networks at the tactical as well as operational decision level to be used by decision makers both in off-line planning and real time management. To specify the Integrated System, a reference model is developed relying on a top-down metamodeling procedure. These innovative research results are a contribution to bridge the gap and to propose not only a systematic modeling approach devoted to describe a generic multi-actor logistic system, but also a management technique based on a closed loop strategy. The second example of application is focused on a topic that is widely discussed in scientific literature related to the study of the multi-actor collective behaviors in a distributed network. The interaction protocols that allow the agents to reach the convergence to a common value is called consensus or agreement problem. This research problem is particularly studied in the context of cooperative control of multi-agent systems because the agents are autonomous, independent and have to interact in a distributed network. The presented research results address the investigation of new and fast alignment protocols that enhance the performances of the standard iteration protocols for particular topologies of digraphs on the basis of a triangular splitting of the standard iteration matrix. The examined examples, the models and the methodologies applied to analyze them, are very different in the two cases and this testifies the large extent of research problems related to the multi-actor systems.L’analisi di modelli e metodi da sviluppare e da applicare nel contesto dei sistemi multi-attoriali costituisce un tema molto variegato e discusso nella letteratura scientifica internazionale. I sistemi multi-attoriali sono sistemi che si contraddistinguono per la presenza di molti elementi autonomi diversi tra loro, di molteplici decisori e di complesse regole che determinano la comunicazione, il coordinamento e la connessione all'interno di tali sistemi. Frequentemente, facendo riferimento a sistemi multi-attoriali, Multi-Actor Systems, si richiama il tema molto attuale dei sistemi multi agente, Multi-Agent Systems. Diffusisi a partire dal 1980, i sistemi multi agente sono spesso studiati in relazione alle metodologie di sviluppo dell'ingegneria del software. Nel presente lavoro di tesi, il tema dei sistemi multi-agente, ed in particolare di quelli multi-attoriali, non viene analizzato in questo contesto, ma in relazione alle tecniche decisionali da adottare per gestire sistemi caratterizzati da un alto livello di complessità. In tale ambito, i risultati presentati all'interno di questa dissertazione sono focalizzati sullo sviluppo e sulla realizzazione di nuovi metodi e di nuove metodologie, in grado di affrontare la gestione della complessità dei sistemi multi-attoriali. Vengono in particolare esaminate due diverse problematiche, in due contesti completamente diversi e con tecniche differenti, a testimoniare le vaste applicazioni che riguardano i sistemi multi-attoriali. I problemi analizzati sono incentrati, in primo luogo, su un'applicazione inerente la gestione di sistemi logistici intermodali ed, in secondo luogo, sullo studio delle regole o protocolli di interazione in una rete distribuita di agenti autonomi. Per quanto riguarda l'aspetto legato ai sistemi intermodali di trasporto, un tema molto discusso nella letteratura scientifica recente, l'analisi si focalizza sulla gestione della loro sempre crescente complessità, tramite l'utilizzo di sistemi dell'Information and Communication Technology, ICT. Questi strumenti richiedono metodi e modelli che sono innovativi rispetto a quanto è presente nella letteratura scientifica, all'interno della quale è stata riscontrata la mancanza di un approccio sistematico e sufficientemente ad alto livello per la realizzazione di una metodologia in grado di descrivere allo stesso tempo sia la molteplicità di elementi che influenzano le dinamiche e le informazioni, sia le strutture decisionali dei sistemi intermodali. L'innovazione dei risultati presentati in questa tesi si focalizza proprio sull'esigenza di proporre un sistema integrato, Integrated System (IS), basato su un metamodello delle reti intermodali di trasporto, che fornisca un valido supporto ai decisori sia a livello tattico che operativo. Il secondo aspetto affrontato in questa tesi riguarda un altro argomento di largo ed attuale interesse nella letteratura scientifica, che viene comunemente chiamato problema del consenso. Questo problema affronta lo studio di come diversi agenti autonomi collocati su una rete distribuita siano in grado di comunicare e di accordarsi su un valore comune, senza la presenza di un decisore centrale. A questo scopo ci sono degli algoritmi che specificano le regole o protocolli di interazione tra i diversi agenti. In tale contesto, i risultati proposti si focalizzano su alcune problematiche rappresentate dal protocollo classico del consenso e soprattutto sulla sua scarsa efficienza in particolari conformazioni delle reti di agenti. Il lavoro di tesi propone, quindi, un approccio di suddivisione, splitting, della matrice standard di iterazione, di tipo triangolare, che presenta notevoli vantaggi in termini di performance rispetto all'algoritmo classico. Lo studio di problemi multi-attoriali, pertanto, richiede lo sviluppo di innovative metodologie decisionali e di nuovi metodi di gestione delle comunicazioni, per rispondere al livello sempre crescente di complessità, offrendo in questo modo alcuni spunti molto interessanti per la ricerca.XXIV Ciclo198

    Electronic Seals and their Influence on the Dynamics of Container Logistics

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    After events 9/11 the unpredictable changes have affected the global container flows in international affairs. In order to define and explore the trade-off between international security requirements and reasonably practicable measures for business, the analysis of one of the application of e-seal technology, promising to improve container transportation processes, have been evaluated in this doctoral research. The intent of this research is to investigate the impact of container detection intrusion technology on dynamics of container logistics processes at container terminals and on the complete network. In this study a model for container transhipment between two continents through several see ports consisting of several maritime terminals and customs gates is developed. In this scenario we compare transhipment processes for three different types of container seals. One type is when containers are equipped with conventional mechanical seals, the next one is an e-seal without decision making, and the last one is an e-seal with a possibility to make routing decisions. These three cases are compared and the difference in dynamics of the transport processes is investigated. First we apply the methods of queuing theory as a most suitable mathematical tool for the analysis of the dynamics. We show that this theory works effectively in case of small number of nodes. However it turns out that we arrive at its limitations when the number of nodes becomes large. For this reason we continue our investigations with help of simulation technique by means of MATLAB that has been applied to a generic container logistic network. Further we also have estimated the economical effectiveness of investments in new container secure devices. It is evaluated whether the electronic seals bring more security for container flows. As well we have investigated their influence on the business efficiency for private sector. The evaluation and analysis of modifications in dynamics of physical container flows have been accomplished through the global container supply network in the first part of the thesis. In the second main part of the doctoral research the cost-benefit analysis shows the possible costs and benefits through the implementation and use of secure container electronic seals in global container network. In this work we have determined the most feasible advantages of application of e-seals technology and the framework of its application. The influence of different types of e-seals on the dynamics of container logistics flows has been investigated, simulated and modelled analytically in the global network; various scenarios have been developed and considered to include the most happened situations in the practical cases. An evaluation model based on the cost-benefit analysis has been proposed and approved by different business cases for adoption of different types of e-seals in container system. The returns on investment index have been calculated to compare the investments in security electronic devices under different initial conditions
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