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The purpose of this paper is to present research in the area of the applications of knowledge‐based and constraint programming (CP)‐driven methodology in production…
The purpose of this paper is to present research in the area of the applications of knowledge‐based and constraint programming (CP)‐driven methodology in production planning and development of decision‐making software supporting scheduling of multi‐robot in a multi‐product job shop, taking into account imprecise (fuzzy) activity specification, and resource sharing by some industrial processes that simultaneously produce different products.
Applications of the knowledge‐based, logic‐algebraic and CP‐driven approach for multi‐robot task allocation problem and generating of fuzzy plan/schedule of production activities for a given period of time.
This paper illustrates the useful information that can be obtained from fuzzy and crispy‐like schedule describing production activities in a multi‐product job shop.
The use of knowledge‐based and CP‐driven methodology for production planning in a multi‐product job shop was a very effective method dedicated to solve typical decision problems in the area of project‐driven production flow management applied in make‐to‐order manufacturing.
The methodology discussed in the paper can be used to design fuzzy Gantt diagrams, which define admissible schedule of production orders for a given period of time.
The paper's contribution covers various issues of decision making while employing the knowledge‐ and CP‐based framework. The proposed approach provides the framework allowing one to take into account distinct (pointed), and imprecise (fuzzy) data, in a unified way and treat it in a unified form of a discrete, constraint satisfaction problem.
The purpose of the paper is to introduce the dynamic phasor modelling (DPM) approach for stability investigation and control design of single-phase phase-locked loops…
The purpose of the paper is to introduce the dynamic phasor modelling (DPM) approach for stability investigation and control design of single-phase phase-locked loops (PLLs). The aim is to identify the system instabilities not predicted using the existent analysis and design methods based on the simplified average model approach.
This paper starts by investigating the performance of three commonly used PLL schemes: the inverse park-PLL, the second-order generalised integrators (SOGI)-frequency-locked loop and the enhanced-PLL, designed using the simplified average model and will show that following this approach, there is a mismatch between their actual and desired transient performance. A new PLL design method is then proposed based on the DPM approach that allows the development of fourth-order DPM models. The small-signal eigenvalues analysis of the fourth-order DPM models is used to determine the control gains and the stability limits.
The DPM approach is proven to be useful for single-phase PLLs stability analysis and control parameters design. It has been successfully used to design the control parameters and to predict the PLL stability limits, which have been validated via simulation and experimental tests consisting of grid voltage sag, phase jump and frequency step change.
This paper has introduced the use of DPM approach for the purpose of single-phase PLL stability analysis and control design. The approach has enabled accurate control gains design and stability limits identification of single-phase PLLs.
As the speed, density, power dissipation, and overall performance of semiconductor chips continue to improve, electronic equipment designers are finding that their ability…
As the speed, density, power dissipation, and overall performance of semiconductor chips continue to improve, electronic equipment designers are finding that their ability to utilise new, high performance ICs is limited by the electrical performance, cost and turnaround time associated with the higher levels of packaging and interconnection. With the evolution of silicon foundries, CAD systems, logic array and standard cell technology, the designer now has the ability to develop and implement custom IC functions rapidly at a fraction of the cost and time associated with full custom IC development. The driving force for this evolution is the need for reduction of product development time and cost. As electronic product life cycles continue to decrease, so must the development time. Although the need to reduce component development times has been acted on first by the semiconductor manufacturers, suppliers of packaging and interconnection components are also feeling the need to provide customised designs rapidly and at low cost. Unilayer II is a discrete wire circuit board technology with a wiring density capability approximating that of multilayer printed wiring boards. However, since the wiring is defined in software and implemented on a numerically controlled wiring machine, the time and cost associated with development, and also with wiring changes, is greatly reduced. This paper presents the results of extensive electrical testing performed to characterise the electrical performance of the discrete wire Unilayer II transmission lines. Characteristic impedance, propagation velocity, capacitance, inductance, and crosstalk are discussed in detail.
Over the past three decade, China has established a housing finance system that borrows from the collective experiences of advanced economies. After examining the…
Over the past three decade, China has established a housing finance system that borrows from the collective experiences of advanced economies. After examining the evolution of China’s housing finance system, the paper focuses on analyzing its challenges and recent changes. The paper argues that China’s highly-centralized financial system prefers financial stability but neglects financial liberalization, and then resulted in severe financial repression, which hurts the efficiency and equality of the housing finance service. After recovering from the 2008 financial crisis via high-cost financial intervention, China took some policy innovations to promote a decentralized finance mechanism, expand finance resources, and support affordable housing financing, through which China hopes to provide a more stable, affordable, and equal housing finance service to help more households own homes.
This chapter uses the case of Tay as a basis for exploring Artificial Intelligence (AI) and its implications for corporate social responsibility (CSR). We explore issues…
This chapter uses the case of Tay as a basis for exploring Artificial Intelligence (AI) and its implications for corporate social responsibility (CSR). We explore issues with AI in relation to two of Roome's (2005) CSR agendas – responsible business practices and consumer responsibility. Then, we build a framework for approaching AI that connects user and designer perspectives, pointing out key concepts and opportunities for public relations (PR) professionals to engage with both uses for and development of AI in the workplace. We point out the ability of AI, as a technology, to turn the action of connecting to publics from a front office to a back office endeavor. Also, we advocate for PR's need, as a field, to rethink potential changes resulting from the integration of AI into organizations which can affect PR practice at a fundamental level. Finally, we propose ways for PR practitioners, educators, and researchers to consider integrating this understanding of AI into their work.
The increasing use of high switching speed systems in both microwave electronics and high speed logic devices has created the need for printed circuit boards which are…
The increasing use of high switching speed systems in both microwave electronics and high speed logic devices has created the need for printed circuit boards which are based on low dielectric constant and low loss materials. In addition, these circuit materials must be capable of withstanding elevated temperatures typical of hostile service environments and of board fabrication processes. Such low dielectric constant rigid boards are commercially available from a few sources. However, there is a growing demand for low dielectric constant flexible printed circuit boards for interconnecting rigid boards or in rigid/flex applications where high speed, fast rise times, controlled impedance and low crosstalk are important. A new family of thin laminates which are suitable for fabrication of flexible low dielectric constant printed circuit boards have been developed by Rogers Corporation. These circuit materials are called ROhyphen;2500 laminates and offer flexible interconnections in high speed electronic systems. RO‐2500 circuit materials are based on microglass reinforced fluorocarbon composites and have a typical dielectric constant of 25. The transmission line properties of these materials have been evaluated by the IPC‐FC‐201 test method. The results indicated that these circuit materials improve the propagation velocity by about 10% and the rise time by about 30% when compared with the same geometry, polyimide film based, flexible PCs in stripline constructions. Also, dimensional stability of these laminates after etch and heat ageing is improved over that of the standard flex circuit materials based on polyimide film. RO‐2500 laminate properties have been evaluated by the IPC‐TM‐650 test methods, which are widely accepted by the flexible PCB industry.
In morphological studies analysis, rather than intuitive explanations, of differences pertaining to the man-made environment requires an understanding of the relational or…
In morphological studies analysis, rather than intuitive explanations, of differences pertaining to the man-made environment requires an understanding of the relational or configurational structure of that specific spatial system. Space Syntax is a set of techniques for describing and analyzing those relational or configurational properties of man made environments. Space Syntax tries to clarify these properties and their meanings by mathematical and graphical analysis to interpret them on a scientific basis. Originally conceived by Prof. B. Hillier and his colloquies in the 1980's as a tool to help architects simulate the likely affects of their designs, it has since grown to become a tool used in a variety of research areas and design applications. This study attempts to formulate the various spatial patterns that have been formed through the history of Trabzon, by means of Space Syntax techniques in a concrete way. It is suggested that the analysis techniques of Space Syntax, supported by a wide range of knowledge, have contributed greatly in the formulation of spatial models in concrete form, further intuition, and can be accepted as a useful tool for defining similarities and differences between different home environments.
The urban renewal process in neighbourhoods with well-rooted communities often reveals the ties between people and spaces, and highlights the inextricable links between…
The urban renewal process in neighbourhoods with well-rooted communities often reveals the ties between people and spaces, and highlights the inextricable links between social and physical structures. The residents of three neighbour-hoods in the city of Barcelona–Trinitat Nova, Plus Ultra and Vallcarca–have endured and fought against the threat of radical urban renewals planned by the municipal authorities for decades, and their efforts have only recently been rewarded with the acceptance of their demands by local administrations. In this period, residents organized themselves to defend their vision of the place against official plans, a vision which was a collective construction of personal memories and historical evidences. In the PROHABIT research project, we have undertaken an interdisciplinary study, involving architects-planners and social and environmental psychologists, to understand the process of construction of a sense of community and place identity in three neighbourhoods. The study has highlighted the need to overcome the divisions between social sciences and design disciplines, between the real world of experience and the abstract world of design thinking. In this regard, the work conducted in this project offers some insights into the need to create a holistic understanding of today's urban environment, and how architects and planners need to develop skills and methods to enable them to form part of the open and participatory planning systems which our contemporary urban environments demand.
The interlibrary loan service was and is an ‘open ended’ service. The gross characteristics were known and details of each transaction were on record. What was not known…
The interlibrary loan service was and is an ‘open ended’ service. The gross characteristics were known and details of each transaction were on record. What was not known was the pattern of interaction between readers, the science section and the co‐operating libraries. This analysis is restricted to indicating this aspect. An alternative approach outlining the use to which information on the publications borrowed is put has been published earlier (WOODWARD, W. B., The management of periodical subscriptions in the science section of the University Library, Durham, Aslib Proceedings, 27 (9), September 1975, p. 385–8).