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The purpose of this paper is to design and implement a directly cooled photovoltaic thermal (PV/T) hybrid system.

The research design subjects, instruments and methods that were used to collect data are as detailed in the paper. Two polycrystalline photovoltaic (PV) modules were used in this study.

The directly water-cooled PV module (PV/T) was found to operate better as compared to a naturally cooled module for the first three months. The PV/T initially operated at a higher electrical efficiency for 87 per cent of the day. The monthly energy-saving efficiency of the PV/T was found to be approximately 61 per cent, while the solar utilisation of the naturally cooled PV module M1 was found to be 8.79 per cent and that of M2 was 47.93 per cent.

The major limitation was the continued drop in efficiency after the first three months of the PV/T placed outdoors. The fall in the efficiency was attributed to water ingress.

Direct water cooling of PV modules is possible, only that a better sealing is needed to prevent water ingress.

PV air cooling has been researched on. Use of water as a cooling medium has been carried out using serpentine pipes or riser tube, and no direct water cooling on the back of the module has been researched on.

Pipe‐spool module assembly involves a variety of uncertain factors and constraints, which complicate the assembly scheduling process. These factors also pose a challenge for the scheduler who struggles to produce a schedule that optimizes both the use of available resources (e.g. space) and meets the project's delivery deadlines. In the relatively quick production cycle of module assembly, the scheduling process plays an operative role. Thus, automation of the process would enhance productivity of the schedule updating process. This paper seeks to address this issue.

A simulation‐based approach is presented for scheduling pipe‐spool module assembly. This approach incorporates physical and logical constraints. General purpose simulation (GPS) is used to model these logical and heuristic constraints.

The application of the proposed model to an actual case study demonstrates the significant improvement in the assembly schedule when compared to traditional CPM‐based scheduling techniques.

The proposed model allows schedulers to experiment with various rules in order to improve the scheduling process by, for example, instantly updating the schedule.

The purpose of this paper is to design and construct a low‐cost current‐voltage tester, bearing in mind the short falls of the existing testers and the ever‐increasing price of the testers currently on the market. The I‐V tracer presented in this paper uses a variable external power supply unit (PSU) as the load, in order to obtain the entire operating range of a PV module from open circuit through maximum power to short circuit condition.

The I‐V tracer presented in this paper was divided into three main sections, mainly the data acquisition system (DAS), which comprises an A/D computer card, temperature card, electromechanical relays, current and voltage transducers, aluminum housed resistors and power MOSFETS, the variable load (programmable variable PSU) and finally the signal processing unit. These components were integrated and finally interfaced to a PC.

The results obtained using this system compared with the capacitive tester show a low percentage difference of <1 from the comparative I‐V curves measured. The results measured by the PSU tester are also of high accuracy. The findings also demonstrated the fact that most of the components found in most university laboratories can be used to build the PSU tester and still obtain highly accurate results.

Since some components are semiconductors, which have a limited lifetime, they need to be changed if they fail. Mostly the MOSFETS should be replaced when no switching signal is sent.

This low‐cost PSU tester is suitable for researchers in disadvantaged institutions whose research capabilities are limited due to the high cost of this equipment.

The PSU tester uses a variable power supply as the load to measure PV module I‐V curves. The system is capable of measuring up to eight modules at the same time, making it possible to analyze PV modules within the same time frame.

Media considerations are pedagogical rather than technological in nature. In online courses, we use technology to enable learner interaction. In this chapter, we focus on a process through which we identify media that will help bring our course to life. Technology tools come and go, quickly. While some specific tools are suggested, it is the process by which to identify and select media that is enduring. We begin with a discussion of media-enabled course activities that are used to guide the selection process. The 10 activities are organized by type of interaction they represent and the media characteristics they require. Media have affordances or functions that can be matched with identified course activities to meet learner interaction needs. These needs help to narrow the scope of our selection decisions. After exploring a variety of functions and tools, we exemplify the media selection process. We extend the work started in previous chapters by identifying media needs in light of design and interaction decisions under the playground and symphony metaphors. In so doing, we demonstrate how the phases of the redesign process inform our technology choices.

This paper deals with the organizing of interactive product development. Developing products in interaction between firms may provide benefits in terms of specialization, increased innovation, and possibilities to perform development activities in parallel. However, the differentiation of product development among a number of firms also implies that various dependencies need to be dealt with across firm boundaries. How dependencies may be dealt with across firms is related to how product development is organized. The purpose of the paper is to explore dependencies and how interactive product development may be organized with regard to these dependencies.

The analytical framework is based on the industrial network approach, and deals with the development of products in terms of adaptation and combination of heterogeneous resources. There are dependencies between resources, that is, they are embedded, implying that no resource can be developed in isolation. The characteristics of and dependencies related to four main categories of resources (products, production facilities, business units and business relationships) provide a basis for analyzing the organizing of interactive product development.

Three in-depth case studies are used to explore the organizing of interactive product development with regard to dependencies. The first two cases are based on the development of the electrical system and the seats for Volvo’s large car platform (P2), performed in interaction with Delphi and Lear respectively. The third case is based on the interaction between Scania and Dayco/DFC Tech for the development of various pipes and hoses for a new truck model.

The analysis is focused on what different dependencies the firms considered and dealt with, and how product development was organized with regard to these dependencies. It is concluded that there is a complex and dynamic pattern of dependencies that reaches far beyond the developed product as well as beyond individual business units. To deal with these dependencies, development may be organized in teams where several business units are represented. This enables interaction between different business units’ resource collections, which is important for resource adaptation as well as for innovation. The delimiting and relating functions of the team boundary are elaborated upon and it is argued that also teams may be regarded as actors. It is also concluded that a modular product structure may entail a modular organization with regard to the teams, though, interaction between business units and teams is needed. A strong connection between the technical structure and the organizational structure is identified and it is concluded that policies regarding the technical structure (e.g. concerning “carry-over”) cannot be separated from the management of the organizational structure (e.g. the supplier structure). The organizing of product development is in itself a complex and dynamic task that needs to be subject to interaction between business units.

Whole garment knitwear is one of the knitwear development trends in the foreseeable future for its advantages of environmental friendliness and wearing comfort. However, the development of new styles of the whole garment knitwear requires both fashion design and computer programming, which makes it time-consuming and difficult. In this paper, a whole garment knitted skirt template Library is introduced to solve this problem.

The template library composes of silhouette module, design element module and parts shaping technology module. It was built based on a comprehensive investigation of design and technology. By adhering to the principle of similarity and reusability, the template library of whole garment knitted skirts was established through the innovative design and hierarchical classification of compressed patterns and package patterns.

With the template library, more than 7.7 × 1025 package pattern templates can be generated through the permutation and combination of the package pattern templates of design elements and parts shaping technology.

The results indicated that it can accelerate the design process and improve the design efficiency of new styles with the template library. This approach can also provide inspiration for the designers and realize rapid response and personalized customization of knitted garment production. In addition, the whole garment templates can be applied into constructing other types of clothing template libraries, such as jackets, pants, etc.

The purpose of this paper is to discuss the recently developed multi-physics computational model for the conventional Gas Metal Arc Welding (GMAW) joining process that has been upgraded with respect to its predictive capabilities regarding the spatial distribution of the mechanical properties controlling the ballistic limit (i.e. penetration resistance) of the weld.

The original model consists of five modules, each dedicated to handling a specific aspect of the GMAW process, i.e.: electro-dynamics of the welding-gun; radiation-/convection-controlled heat transfer from the electric arc to the workpiece and mass transfer from the filler-metal consumable electrode to the weld; prediction of the temporal evolution and the spatial distribution of thermal and mechanical fields within the weld region during the GMAW joining process; the resulting temporal evolution and spatial distribution of the material microstructure throughout the weld region; and spatial distribution of the as-welded material mechanical properties. The model is upgraded through the introduction of the sixth module in the present work in recognition of the fact that in thick steel GMAW weldments, the overall ballistic performance of the armor may become controlled by the (often inferior) ballistic limits of its weld (fusion and heat-affected) zones.

The upgraded GMAW process model is next applied to the case of butt-welding of MIL A46100 (a prototypical high-hardness armor-grade martensitic steel) workpieces using filler-metal electrodes made of the same material. The predictions of the upgraded GMAW process model pertaining to the spatial distribution of the material microstructure and ballistic-limit-controlling mechanical properties within the MIL A46100 butt-weld are found to be consistent with general expectations and prior observations.

To the authors’ knowledge, the present work is the first reported attempt to establish, using computational modeling, functional relationships between the GMAW process parameters and the mechanical properties controlling the ballistic limit of the resulting weld.

Notes, in recent years, an increase of interest in the field of service parts inventory ‐ particularly in the computer industry. Explains that the computer industry is a highly competitive industry; products have to be repaired as quickly as possible, since slow repair can lead to loss of future business to competitors with better service reputations. Maintains that a good reputation is therefore closely linked to the availability of spare parts on the market. Using a real‐life case study, elaborates on the management and control of service‐parts inventory and gives a brief overview of the contemporary literature on the subject. Presents the solution approach adopted and the results of the study, which indicate that significant savings can be realized through good management of service‐parts inventory.

A real-time production scheduling method for semiconductor back-end manufacturing process becomes increasingly important in industry 4.0. Semiconductor back-end manufacturing process is always accompanied by order splitting and merging; besides, in each stage of the process, there are always multiple machine groups that have different production capabilities and capacities. This paper studies a multi-agent based scheduling architecture for the radio frequency identification (RFID)-enabled semiconductor back-end shopfloor, which integrates not only manufacturing resources but also human factors.

The architecture includes a task management (TM) agent, a staff instruction (SI) agent, a task scheduling (TS) agent, an information management center (IMC), machine group (MG) agent and a production monitoring (PM) agent. Then, based on the architecture, the authors developed a scheduling method consisting of capability & capacity planning and machine configuration modules in the TS agent.

The authors used greedy policy to assign each order to the appropriate machine groups based on the real-time utilization ration of each MG in the capability & capacity (C&C) planning module, and used a partial swarm optimization (PSO) algorithm to schedule each splitting job to the identified machine based on the C&C planning results. At last, we conducted a case study to demonstrate the proposed multi-agent based real-time production scheduling models and methods.

This paper proposes a multi-agent based real-time scheduling framework for semiconductor back-end industry. A C&C planning and a machine configuration algorithm are developed, respectively. The paper provides a feasible solution for semiconductor back-end manufacturing process to realize real-time scheduling.

The Royal Society of Chemistry (RSC) Library offers a full range of library and information services to the Society's 42,000 members and the chemical community as a whole. Computers were first used in the Library in 1977 for online searching. In 1987, the cataloguing and circulation modules of the Data Trek automated library management system were installed and in mid‐1988 a Novell network with four workstations was set up. By mid‐1989, an OPAC was in place and the card catalogue was only used for pre‐1986 items. In 1990, serials management and acquisitions modules together with three more workstations were added to the network; a CD‐ROM player was also installed. The paper gives details of this and related development work and also how a total file server disc crash was dealt with in early 1991.