Bibliography: pages 149-150. / The subject of physical distribution was first examined in the early 1900s. It was developed and refined especially during World II under the name of 'Logistics', and began to be adopted in the field of business from the 1950s. From the 1960s onwards, national bodies have been established, both in the U.S. and the U.K., and works and theories have been published leading to the establishment of journals and the establishment of formal education programmes all dealing with physical distribution. A review of published works on the subject was undertaken. Some books were studied, as well as a number of journal articles dating from the early 1970s. No suitable references were obtained dealing with the subject in a South African context. A project was also carried out to design a system for distributing garments in a hanging mode. The thesis thus concerns a general review of physical distribution management and the distribution of goods and services throughout business and industry, with an emphasis being placed on south African conditions. The principal objectives of this study were to examine and review the state-of-the-art of the general theory and the use of physical distribution, to suggest means of applying it in South Africa and to briefly examine future trends and developments. These objectives were achieved by examining from books and articles the concept and theory of distribution, its interrelationships with aspects such as marketing, production and business organisations, and its management in business organisations: by discussing some characteristics of South African business and industry; by examining certain areas that provide the greatest potential for improvements: by discussing a project carried out to design a distribution system for hanging garments merchandise; and by examining future trends both overseas and in South Africa. Physical distribution is shown to be an important subject for business and society and for the economy as a whole. It is always changing in a dynamic environment and requires constant monitoring. This thesis shows how this field, which has been researched and developed overseas, is affected by local conditions and should be applied to specific areas in South Africa.

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In recent years, with the rapid development of electric and electronic technology, the All-Electric Aircraft (AEA) concept has attracted more and more attention, which only utilizes the electric power instead of conventional hydraulic and pneumatic power to supply all the airframe systems. To meet the power requirements under various flight stages and operating conditions, the AEA approach has resulted in the current aircraft electrical power generation capacity up to 1.6 MW. To satisfy the power quality and stability requirements, the advanced power electronic interfaces and more efficient power distribution systems must be investigated. Moreover, with the purpose of taking the full advantages of available electrical power, novel dynamic power distribution management research and design for an AEA must be carried out. The main objective of this thesis is to investigate and develop a methodology of more efficient power distribution management with the purpose of minimizing the rated power generating capacity and the mass of the electrical power system (EPS) including the power generation system and the power distribution system in an AEA. It is important to analyse and compare the subsistent electrical power distribution management approaches in current aircraft. Therefore the electrical power systems of A320 and B777, especially the power management system, will be discussed in this thesis. Most importantly the baseline aircraft, the Flying Crane is the outcome of the group design project. The whole project began in March 2008, and ended in September 2010, including three stages: conceptual design, preliminary design and detailed design. The dynamic power distribution management research is based on the power distribution system of the Flying Crane. The main task of the investigation is to analyse and manage the power usage among and inside typical airframe systems by using dynamic power distribution management method. The characteristics and operation process of these systems will be investigated in detail and thoroughly. By using the method of dynamic power distribution management, all the electrical consumers and sub-systems powered by electricity are managed effectively. The performance of an aircraft can be improved by reducing the peak load requirement on board. Furthermore, the electrical system architecture, distributed power distribution system and the dynamic power distribution management system for AEA are presented. Finally, the mass of the whole electrical power system is estimated and analysed carefully.

Diss. Linköping : Univ., 2002.

No / This research aims to conduct an exploratory analysis into current industrial reverse logistics practice in business-to-business (B2B) and business-to-customer relationships (B2C), and determine the financial and operational impact of customer non-compliance in returning distribution equipment back to their source. The analysis was conducted over multiple industry sectors using qualitative research techniques. The research sample included seven industry sectors, providing a response rate of 72 per cent (53 sources approached). The focus was on both B2B and B2C relationships to determine similarities and differences in financial and operational repercussions. The research findings indicate that the efficacy of the reverse logistics system can be undermined by lack of customer compliance, with losses of up to £140 million (B2B). In both B2B and B2C relationships, there is evidence of suppliers suffering financial loss due to customer non-compliance. Due to the small scale of the analysis and the breadth of the industry sectors investigated, these results are not generalisable, but do indicate that this is an area, which could undermine supply chain effectiveness. Practical implications – Non-compliance of this nature carries a direct and highly applicable cost for manufacturers and distributors in the practitioner arena. Suppliers within industry need to acknowledge this issue and manage their reverse logistics more effectively. This paper adopts an innovative focus on an understated feature of the reverse logistics cycle, i.e. the recycling of distribution equipment used to transport outbound and returned products. The paper identifies a range of options, which practitioners can use as guidance when managing the returns system.

Distributed simulation is an enabling concept to support the networked interaction of models and real world elements that are geographically distributed. This technology has brought a new set of challenging problems to solve, such as Data Distribution Management (DDM). The aim of DDM is to limit and control the volume of the data exchanged during a distributed simulation, and reduce the processing requirements of the simulation hosts by relaying events and state information only to those applications that require them. In this thesis, we propose a new DDM scheme, which we refer to as dynamic grid-based DDM. A lightweight UNT-RTI has been developed and implemented to investigate the performance of our DDM scheme. Our results clearly indicate that our scheme is scalable and it significantly reduces both the number of multicast groups used, and the message overhead, when compared to previous grid-based allocation schemes using large-scale and real-world scenarios.

Dissertação apresentada para obtenção do grau de Mestre, na Faculdade de Engenharia da Universidade do Porto, sob a orientação do Prof. João Paulo Tomé Saraiva

Installation and utilization of residential distribution transformers has not changed substantially over a long period of time. Utilities typically size their transformers based on a formula that takes into account broadly what types and how many dwellings will be connected. Most new residential dwellings feature 200 Amp service per household with an anticipated energy demand of under 20,000 kWh per year. Average electrical energy consumption varies from state to state but averages to 11,280 kWh per year. Energy demand is expected to fall into a typical residential load curve that shows increased demand early in the morning, then decreasing during the day and another peak early to late evening. Distribution transformers are sized at the limit of the combined evening peak with the assumption that the transformer has enough thermal mass to absorb short overloads that may occur when concurrent loading situations among multiple dwellings arise. The assumption that concurrent loading is of short duration and the transformer can cool off during the night time has been validated over the years and has become standard practice. This has worked well when dwelling loads follow an averaging scheme and low level of coincidence. With the arrival of electric vehicles (EV's) this assumption has to be reevaluated. The acquisition of an electric vehicle in a household can drive up energy demand by over 4000 kWh per year. Potentially problematic is the increased capacity of battery packs and the resulting proliferation of Level 2 chargers. The additional load of a single Level 2 charger concurring with the combined evening peak load will push even conservatively sized distribution transformers over their nameplate rating for a substantial amount of time. Additionally, unlike common household appliances of similar power requirements such as ovens or water heaters, a Level 2 battery charger will run at peak power consumption for several hours, and the current drawn by the EVs has very high levels of harmonic distortion. The excessive loading and harmonic profile can potentially result in damaging heat build-up resulting in asset degradation. In this thesis I present a device and method that monitors pole mounted distribution transformers for overheating, collect and wirelessly upload data and initiate commands to chargers to change output levels from Level 2 to Level 1 or shut down EV charging altogether until the transformer returns into safe operational range.