A survey of self organisation in future cellular networks

This article surveys the literature over the period of the last decade on the emerging field of self organisation as applied to wireless cellular communication networks. Self organisation has been extensively studied and applied in adhoc networks, wireless sensor networks and autonomic computer networks; however in the context of wireless cellular networks, this is the first attempt to put in perspective the various efforts in form of a tutorial/survey. We provide a comprehensive survey of the existing literature, projects and standards in self organising cellular networks. Additionally, we also aim to present a clear understanding of this active research area, identifying a clear taxonomy and guidelines for design of self organising mechanisms. We compare strength and weakness of existing solutions and highlight the key research areas for further development. This paper serves as a guide and a starting point for anyone willing to delve into research on self organisation in wireless cellular communication networks

Past, state-of-the-art and future of intralogistics in relation to megatrends

Nakon kratkog pregleda istorije intralogistike, ovaj rad izučava pogled na navedene tehnologije. One su u vezi sa t.z.v. 'megatrendovima' kao što su globalizacija, urbanizacija, demografske i klimatske promene, za koje se očekuje da donesu globalne promene u nekoliko sledećih decenija i koje će najverovatnije odrediti buduću ulogu intralogistike i fokus istraživanja u ovoj oblasti.After briefly reviewing the history of intralogistics, this paper examines the outlook for the technologies concerned. This is related to the so-called 'megatrends', such as globalisation, urbanisation, demographic shifts and climate change, which are expected to bring about major global transformations over the next few decades, and which are also likely to determine the future functions of intralogistics and the focus of research in the field

Past, state-of-the-art and future of intralogistics in relation to megatrends

Nakon kratkog pregleda istorije intralogistike, ovaj rad izučava pogled na navedene tehnologije. One su u vezi sa t.z.v. 'megatrendovima' kao što su globalizacija, urbanizacija, demografske i klimatske promene, za koje se očekuje da donesu globalne promene u nekoliko sledećih decenija i koje će najverovatnije odrediti buduću ulogu intralogistike i fokus istraživanja u ovoj oblasti.After briefly reviewing the history of intralogistics, this paper examines the outlook for the technologies concerned. This is related to the so-called 'megatrends', such as globalisation, urbanisation, demographic shifts and climate change, which are expected to bring about major global transformations over the next few decades, and which are also likely to determine the future functions of intralogistics and the focus of research in the field

Automation of ship-to-shore container cranes: A review of state-of-the-art

U radu je prikazan pregled dostignutog stepena razvoja i istraživanja u oblasti automatizacije obalskih kontejnerskih dizalica. Primenom različitih tehnika automatizacije povećava se produktivnost obalskih kontejnerskih dizalica, a sledstveno tome se povećava i efikasnost lučkih terminala kao integralnog dela logističke mreže. U radu je, takođe, prikazan pregled nekih najznačajnijih publikovanih istraživanja iz oblasti upravljanja kod kontejnerskih dizalica, a dati su i principi rada trenutno postojećih uređaja za umirivanje oscilovanja tereta - kontejnera.The paper gives the state-of-the-art of automation of ship-to-shore (STS) container cranes, as the biggest investments in the port terminal system. The automation techniques increase the productivity of the ship-to-shore container crane, and consequently increase the port terminal efficiency, as an integral part of logistic network. The paper also shows a short survey of some most important and recent researches in control of ship-to-shore cranes, and main principles of operation of antis way currently existing devices

Automation of ship-to-shore container cranes: A review of state-of-the-art

U radu je prikazan pregled dostignutog stepena razvoja i istraživanja u oblasti automatizacije obalskih kontejnerskih dizalica. Primenom različitih tehnika automatizacije povećava se produktivnost obalskih kontejnerskih dizalica, a sledstveno tome se povećava i efikasnost lučkih terminala kao integralnog dela logističke mreže. U radu je, takođe, prikazan pregled nekih najznačajnijih publikovanih istraživanja iz oblasti upravljanja kod kontejnerskih dizalica, a dati su i principi rada trenutno postojećih uređaja za umirivanje oscilovanja tereta - kontejnera.The paper gives the state-of-the-art of automation of ship-to-shore (STS) container cranes, as the biggest investments in the port terminal system. The automation techniques increase the productivity of the ship-to-shore container crane, and consequently increase the port terminal efficiency, as an integral part of logistic network. The paper also shows a short survey of some most important and recent researches in control of ship-to-shore cranes, and main principles of operation of antis way currently existing devices

Control of free-ranging automated guided vehicles in container terminals

Container terminal automation has come to the fore during the last 20 years to improve their efficiency. Whereas a high level of automation has already been achieved in vertical handling operations (stacking cranes), horizontal container transport still has disincentives to the adoption of automated guided vehicles (AGVs) due to a high degree of operational complexity of vehicles. This feature has led to the employment of simple AGV control techniques while hindering the vehicles to utilise their maximum operational capability. In AGV dispatching, vehicles cannot amend ongoing delivery assignments although they have yet to receive the corresponding containers. Therefore, better AGV allocation plans would be discarded that can only be achieved by task reassignment. Also, because of the adoption of predetermined guide paths, AGVs are forced to deploy a highly limited range of their movement abilities while increasing required travel distances for handling container delivery jobs. To handle the two main issues, an AGV dispatching model and a fleet trajectory planning algorithm are proposed. The dispatcher achieves job assignment flexibility by allowing AGVs towards to container origins to abandon their current duty and receive new tasks. The trajectory planner advances Dubins curves to suggest diverse optional paths per origin-destination pair. It also amends vehicular acceleration rates for resolving conflicts between AGVs. In both of the models, the framework of simulated annealing was applied to resolve inherent time complexity. To test and evaluate the sophisticated AGV control models for vehicle dispatching and fleet trajectory planning, a bespoke simulation model is also proposed. A series of simulation tests were performed based on a real container terminal with several performance indicators, and it is identified that the presented dispatcher outperforms conventional vehicle dispatching heuristics in AGV arrival delay time and setup travel time, and the fleet trajectory planner can suggest shorter paths than the corresponding Manhattan distances, especially with fewer AGVs.Open Acces

Green vehicle technology to enhance the performance of a European port: a simulation model with a cost-benefit approach

In this paper, we study the impact of using a new intelligent vehicle technology on the performance and total cost of a European port, in comparison with existing vehicle systems like trucks. Intelligent autonomous vehicles (IAVs) are a new type of automated guided vehicles (AGVs) with better maneuverability and a special ability to pick up/drop off containers by themselves. To identify the most economical fleet size for each type of vehicle to satisfy the port's performance target, and also to compare their impact on the performance/cost of container terminals, we developed a discrete-event simulation model to simulate all port activities in micro-level (low-level) details. We also developed a cost model to investigate the present values of using two types of vehicle, given the identified fleet size. Results of using the different types of vehicles are then compared based on the given performance measures such as the quay crane net moves per hour and average total discharging/loading time at berth. Besides successfully identifying the optimal fleet size for each type of vehicle, simulation results reveal two findings: first, even when not utilising their ability to pick up/drop off containers, the IAVs still have similar efficacy to regular trucks thanks to their better maneuverability. Second, enabling IAVs ability to pick up/drop off containers significantly improves the port performance. Given the best configuration and fleet size as identified by the simulation, we use the developed cost model to estimate the total cost needed for each type of vehicle to meet the performance target. Finally, we study the performance of the case study port with advanced real-time vehicle dispatching/scheduling and container placement strategies. This study reveals that the case study port can greatly benefit from upgrading its current vehicle dispatching/scheduling strategy to a more advanced one

Heuristic container placement algorithms

Thesis (Master)--Izmir Institute of Technology, Computer Engineering, Izmir, 2003Includes bibliographical references (leaves: 56-58)Text in English; Abstract: Turkish and Englishviii, 72 leavesWith the growth of transportation over sea; defining transportation processes in a better way and finding ways to make transportation processes more effective have become one of the most important research areas of today. Especially in the last quartet of the previous decade, the computers had become much powerful tools with their impressive amount of data processing cababilites. It was imminent that computers had begun taking serious roles in the system development studies. As a result; constructing models for the processes in container terminals and processing the data with the computers create opportunities for the automation of various processes in container terminals. The final step of these studies is the full automation of terminal activities with software packages that combine various functions focused on various processes in a single system.This study is about a project that had been made for a container terminal owned by a special company. During this study; there had been discussions with experts about the subject, and container handling processes in the terminal had been analyzed in order to define the main structure of the yard management software to be created.This study focuses on the container handling activities over the yard space so as to create a basis for a computer system that will take part in the decisions during the container operations. Object oriented analysis and design methods are used for the definition of the system that will help the decisions in the yard operations. The optimization methodology that will be the core of the container placement decisions is based on using different placement patterns and placement algorithms for different conditions. These placement patterns and algorithms are constructed due to the container handling machinery that was being used in the terminal that this study has been made for