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The purpose of this paper is to introduce an algorithm based only on local extreme analysis of a time sequence to further the detection and diagnosis of inter-turn short circuits and unbalanced voltage supply using vibration signals.

The upper and lower extreme envelopes from a modulated and oscillatory time sequence present a particular characteristic being of, theoretically, symmetrical versions with regard to amplitude reflection around the time axis. Thus, one may say that they carry the same characteristics in terms of waveforms and, consequently, frequency content. These envelopes can easily be built by an interpolation process of the local extremes, maximums and minimums, from the original time sequence. Similar to modulator signals, they contain more detailed and useful information about the required electrical fault frequencies.

Results show the efficiency of the proposed algorithm and its relevance to detecting and diagnosing faults in induction motors with the advantage of being a technique that is easy to implement in any computational code.

A laboratory investigation carried out through an experimental setup for the study of faults, mainly related to the stator winding inter-turn short circuit and voltage phase unbalance, is presented.

The main contribution of the work is the presentation of an alternative tool to demodulate signals which may be used in real applications like the detection of faults in three-phase induction machines.

The development of strategies for energy efficiency optimization in buildings has become a fundamental way to reduce buildings’ environmental impact because the amount of energy consumed by buildings is responsible for one‐third of total global energy consumption. The purpose of this research is to evaluate the performance of buildings in terms of their indoor operative temperature dynamics considering the impact of other neighbouring buildings. The goal of the paper is to verify whether close spatial relationships of buildings and urban morphology within a local network of buildings could cause a considerable effect on indoor thermal behaviour.

The authors simulated buildings in an existing city block in Albany, New York, USA. The block consisted of six single‐family houses.

The results demonstrate that buildings mutually impact the indoor thermal behaviour of other buildings in the network with indoor operative temperature differences of over 20 percent in summer and over 40 percent in winter for the test case examined. The research also compares this result with improvements in indoor operative temperature achieved through traditional envelope improvements. It was found that during the summer, certain envelope improvement strategies have nearly the same impact in terms of indoor thermal behaviour. During winter, the presence of neighbouring buildings causes a variation that is more than double the value of the effect caused by a typical envelope modification.

It is concluded that this mutual impact on indoor operative temperature across spatially proximal buildings should be included in dynamic analyses of buildings. Future research should examine the effect of these indoor operative temperature deviations on the energy performance predictions of buildings in urban and quasi‐urban settings.

The objective of this paper is to provide a brief review of recent developments in the area of applications of ANN, Fuzzy Logic, and Wavelet Transform in fault diagnosis. The purpose of this work is to provide an approach for maintenance engineers for online fault diagnosis through the development of a machine condition‐monitoring system.

A detailed review of previous work carried out by several researchers and maintenance engineers in the area of machine‐fault signature‐analysis is performed. A hybrid expert system is developed using ANN, Fuzzy Logic and Wavelet Transform. A Knowledge Base (KB) is created with the help of fuzzy membership function. The triangular membership function is used for the generation of the knowledge base. The fuzzy‐BP approach is used successfully by using LR‐type fuzzy numbers of wavelet‐packet decomposition features.

The development of a hybrid system, with the use of LR‐type fuzzy numbers, ANN, Wavelets decomposition, and fuzzy logic is found. Results show that this approach can successfully diagnose the bearing condition and that accuracy is good compared with conventionally EBPNN‐based fault diagnosis.

The work presents a laboratory investigation carried out through an experimental set‐up for the study of mechanical faults, mainly related to the rolling element bearings.

The main contribution of the work has been the development of an expert system, which identifies the fault accurately online. The approaches can now be extended to the development of a fault diagnostics system for other mechanical faults such as gear fault, coupling fault, misalignment, looseness, and unbalance, etc.

Provides an introduction into wavelets and illustrates their application with two examples. The wavelet transform provides the analyst with a scaleable time‐frequency representation of the signal, which may uncover details not evidenced by conventional signal processing techniques. The signals used in this paper are Doppler ultrasound recordings of blood flow velocity taken from the internal carotid artery and the femoral artery. Shows how wavelets can be used as an alternative signal processing tool to the short time Fourier transform for the extraction of the time‐frequency distribution of Doppler ultrasound signals. Implements wavelet‐based adaptive filtering for the extraction of maximum blood velocity envelopes in the post processing of Doppler signals.

In response to the growing demand for zero-energy housing, today's home needs not only to be energy-efficient, but also to provide part of its own energy requirements. The energy efficiency may be improved by applying high thermal performance building envelope and passive energy and environmental systems to housing. Micro-power can be generated through the use of renewable energy technologies. This paper is aimed at providing a comprehensive guideline on the design techniques and approaches to the delivery of net zero-energy healthy housing in view of the ÉcoTerra house, which won the Canadian federal government's EQuilibrium sustainable housing competition. The house was built in Eastman in the province of Quebec and it is currently open to the general public in order to sharpen the consumers' awareness of commercially available net zero-energy healthy housing today.

Modern variable‐speed drive systems using frequency converters generate additional audible noise as a result of the voltages that are no longer sinusoidal. Using suitable measures, the purpose of this paper is to find an optimum for minimum noise radiation in the complete drive system.

The main areas to concentrate on to achieve an optimum are the source of excitation itself – the frequency converter, as well as the actual source of the noise, the motor. Optimization measures are drawn‐up using soundscaping with subsequent modal analysis of the actual state. The effectiveness of any changes made can be estimated using simulation techniques. This approach is confirmed by subsequently implementing the selected measures and verifying them by performing the appropriate measurements.

The paper takes care of the increasingly important field of converter‐fed drive systems and their special acoustical challenge. It shows a practical way to reduce audible noise combining measurements and simulations.

Combining the measurement of the acoustic camera with the simulation of modal shapes is a fast way for optimizing an inverter‐fed drive system.

The purpose of this paper is to develop an efficient hybrid method that can collectively address assembly sequence generation (ASG) and exploded view generation (EVG) problem effectively. ASG is an act of finding feasible collision free movement of components of a mechanical product in accordance with the assembly design. Although the execution of ASG is complex and time-consuming in calculation, it is highly essential for efficient manufacturing process. Because of numerous limitations of the ASG algorithms, a definite method is still unavailable in the computer-aided design (CAD) software, and therefore the explosion of the product is not found to be in accordance with any feasible disassembly sequence (disassembly sequence is reverse progression of assembly sequence). The existing EVG algorithms in the CAD software result in visualization of the entire constituent parts of the product over single screen without taking into consideration the feasible order of assembly operations; thus, it becomes necessary to formulate an algorithm which effectively solves ASG and EVG problem in conjugation. This requirement has also been documented as standard in the “General Information Concerning Patents: 1.84 Standards for drawings” in the United States Patent and Trademark office (2005) which states that the exploded view created for any product should show the relationship or order of assembly of various parts that are permissible.

In this paper, a unique ASG method has been proposed and is further extended for EVG. The ASG follows a deterministic approach to avoid redundant data collection and calculation. The proposed method is effectively applied on products which require such feasible paths of disassembly other than canonical directions.

The method is capable of organizing the assembly operations as linear or parallel progression of assembly such that the assembly task is completed in minimum number of stages. This result is further taken for EVG and is found to be proven effective.

Assembly sequence planning (ASP) is performed most of the times considering the geometric feasibility along canonical axes without considering parallel possibility of assembly operations. In this paper, the proposed method is robust to address this issue. Exploded view generation considering feasible ASP is also one of the novel approaches illustrated in this paper.

The aim of this study is to compare the relative efficiency of quality management practices among American, Japanese, and Taiwanese firms located in Taiwan. Data envelope analysis (DEA) technique is used to measure the relative efficiency of these firms. Quality management practices and organizational performances are treated as input and output factors respectively. The firms are grouped in four based on their efficiency levels. These groups are referred to as robustly efficient, marginal efficient, marginal inefficient, and distinctly inefficient units in DEA. The results of the analysis showed that there is a significant difference between the levels of efficiency among the three typologies of firms – American‐, Japanese‐, and Taiwanese‐owned firms. The study found that the efficiency of quality management practices for Japanese‐owned firms is the highest, even though almost all of their employees are Taiwanese; also, American‐owned firms’ efficiency is higher than that of Taiwanese‐owned firms. It was also observed that the ethnocentric quality management practices of foreign firms in Taiwan might have contributed to the inefficiency of Taiwanese firms. The study shows that Taiwanese and US firms can benchmark the efficient practices of Japanese firms in order to be the best‐in‐class.

The integration of information systems must consider various aspects, including the individuals of an organization, cooperating with other vendors, and the connections within this organization. The advantages of integration include shortening the negotiation process among the organization and the cooperating vendors, saving time for the users, and identifying the interface management. However, the greatest difficulties are how to integrate different system platforms and implement technical aspects into a suitable Web‐interface for users to operate. Information technology companies have developed Web Services which rely on the flexibility of the Extended Mark‐up Language. The services not only apply to integrated information systems, but also provide open services in Web environments. This article evaluates the feasibility of Web Services for application in integrated library information systems.

The motivation for this paper stems from the 2001 financial crisis which emerged in the banking industry and spread over the other industries, creating a domino effect. The purpose of this paper is to examine the market efficiency of Istanbul Stock Exchange (ISE) listed non-financial firms from 2000 through 2002.

A four-stage data envelope analysis (DEA) is developed to measure the performance of firms before and after the 2001 financial crisis. At each stage, production, profitability, marketability and overall efficiencies are measured. Further, Malmquist Productivity Index is applied to compare total factor productivity over time.

The findings show that firms are more efficient at the profitability stage than at other stages. However, the 2001 financial crisis eroded profitability efficiency. Overall, ISE-listed firms experienced diseconomies of scale so that many firms were not able to transform production into sales and therefore earnings efficiently, particularly during the crisis period.

The sample is limited to manufacturing companies. All financial firms are excluded from the sample.

This paper extends the three-stage market value efficiency process outlined in Zhu (2000) by adding production stage. It proposes four-stage DEA approach to measure production, profitability, marketability and overall efficiency of ISE-listed firms. To the best of authors’ knowledge, there has been no study using four-stage DEA approach for Turkish firms.