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This paper aims to propose a double-sided switched reluctance linxear generator (DSRLG) exclusively for wave power generation. The initial dimensions are given through design experience and principles. To ameliorate comprehensive performance of the DSRLG, the multi-objective optimization design is processed.

The multi-objective optimization design of the DSRLG is processed by adopting a modified entropy technique for order of preference by similarity to ideal solution (TOPSIS) algorithm. First, sensitivity analyzes on geometric parameters of the DSRLG are conducted to determine several pivotal geometric parameters as optimization variables. Then, the multi-objective optimization is conducted on the basis of initial dimensions. After determination of synthetical evaluation value of each structure parameter, the best dimension scheme of the DSRLG is concluded.

After verification by finite element method simulation and dynamic simulation, the final dimension scheme proves to perform better than the initial scheme. Finally, experiments are conducted to verify the accuracy of both the stable finite element DSRLG model and dynamic simulation system model so that the conclusion of this paper proves to be reliable and compelling.

This paper proposes an improved structure of the DSRLG, which is superior for wave power generation. Meanwhile, a novel modified entropy TOPSIS algorithm is applied to the field of electrical machine multi-objective optimal design for the first time.

The purpose of this paper is to provide an immediate image about the reality of the renewable energies as experienced by an Algerian company.

The adopted approach focused on assessment of renewable energies’ impact (especially the thermal solar power) on the environment and on the economic aspect of an Algerian company.

The perception of environmental dimension is highlighted by means of an evaluation study supported by the calculation of quantities of CO₂ emitted by two power stations (the new hybrid power station of Hassi R’mel (SPPI) and a conventional one (Sonelgaz)).

This research has limitations that the authors plan to study in perspective: assessing the impact of wind systems on the environmental and economic aspects.

The analysis of obtained results shows and puts emphasis on the importance of renewable energies, especially thermal solar power, by identifying and evaluating the environmental and economic aspects of the new hybrid power station of Hassi R’mel (SPPI) and a conventional one (Sonelgaz) and by comparing the importance of their atmospheric emissions.

The paper shows that this new technology represents in theory a solution for environmental problems and could also be economically competitive with conventional energies if wisely exploited.

The purpose of this paper is to provide an insight into the techniques used for the non‐destructive testing (NDT) of non‐metallic structural materials, notably polymer and ceramic composites.

Following a short introduction, this paper first considers methods for testing carbon fibre‐ and glass fibre‐reinforced polymer composites. It then discusses the role of NDT in wind and wave power systems and some of the techniques used to test ceramics and ceramic composites. Brief conclusions are drawn.

This shows that the growing use of non‐metallic engineering materials in critical applications has highlighted the need for a range of advanced NDT methods. While some traditional techniques can be adapted to test these materials, in several instances novel methods are required. These include a range of thermal, ultrasonic, electromagnetic, radiographic and laser‐based technologies.

The paper provides a review of the techniques used and being developed for the non‐destructive testing of non‐metallic engineering materials.

The purpose of this paper is to achieve the multi-objective optimization design of novel tubular switched reluctance motor (TSRM).

First, the structure and initial dimensions of TSRM are obtained based on design criteria and requirements. Second, the sensitivity analysis rules, process and results of TSRM are performed. Third, three optimization objectives are determined by the average electromagnetic force, smoothing coefficient and copper loss ratio. The analytic hierarchy process-entropy method-a technique for order preference by similarity to an ideal solution-grey relation analysis comprehensive evaluation algorithm is used to optimize TSRM. Finally, a prototype is manufactured, a hardware platform is built and static and dynamic experimental validations are carried out.

The sensitivity analysis reveals that parameters significantly impact the performance of TSRM. The results of multi-objective optimization show that the average electromagnetic force and smoothing coefficient after optimization are better than before, and the copper loss ratio reduces slightly. The experimental and simulated results of TSRM are consistent, which verifies the accuracy of TSRM.

In this paper, only three optimization objectives are selected in the multi-objective optimization process. To improve the performance of TSRM, the heating characteristics, such as iron loss, can be considered as the optimization objective for a more comprehensive analysis of TSRM performance.

A novel motor structure is designed, combining the advantages of the TSRM and the linear motor. The established sensitivity analysis rules are scientific and suitable for the effects of various parameters on motor performance. The proposed multi-objective optimization algorithm is a comprehensive evaluation algorithm. It considers subjective weight and objective weight and fully uses the original data and the relational degree between the optimization objectives.

The purpose of this paper is to examine the several methodologies and activities taken to assess the environmental impacts of a $33 million pilot project undertaken through a loan from the Asian Development Bank (ADB) jointly with significant Chinese government investments. The ADB biogas utilization project has supported construction of over 7,500 biogas digesters in more than 140 rural villages. An additional 10,000 biogas digesters are programmed as well as significant investment in biogas production through large‐scale animal agribusinesses. The latter will be supported through investments utilizing the Clean Development Mechanism (CDM).

The paper provides a longitudinal perspective by: looking at the project's Initial Environmental Examination (IEE) undertaken at appraisal; assessing the ongoing energy and environmental monitoring plan currently under way; and examining the potential for the use of Strategic Environmental Assessment (SEA) as a tool for integrating environmental policy considerations on a regional or provincial level in China.

Improved technologies for application of renewable energy – in particular successful application and adoption of biogas digesters at the village level – offer the potential to promote sustainable, cost‐effective growth in agriculture with concurrent positive environmental impacts.

Based on the relative success of ongoing efforts to promote the adoption of biomass technologies, a significant expansion of the bioenergy program is under consideration by the Ministry of Agriculture.

The case study suggests that there is potential for use of SEA as a tool for the establishment of regional or provincial environmental priorities by taking account of information on the economic, social and environmental benefits, costs and risks of adopting a national strategy for biomass utilization. SEA is a recent innovation in China and must be adapted to local conditions.

This paper aims to present a Halbach magnet array linear machine, without an iron core and the electromotive force (EMF) characteristic results.

The linear machine was made with mover coils and a permanent magnet stator without an iron core. For an outline design, the analyzed magnetic density results were compared to the Halbach array with a horizontal array using the 3D finite element analysis. The test was carried out on an experimental system using a prototype linear machine. The EMF of the linear machine, with applied Halbach array magnetic circuit, is verified with the experiment.

The EMF peak value of the Halbach array is larger than the EMF of the horizontal array. Compared to the EMF in the experimental results, the effective value of the Halbach array is 1.69 times greater at an average operation speed of 373 mm/s.

The core-less linear machine has advantages of reduced cogging torque and iron loss because both the stator and the mover do not have an iron core. The stator and rotor will not rust from water. In this paper, it is clear from the basic electrical characteristics that the linear machine, with applied Halbach array, is larger than the EMF of the horizontal array.

The maritime freight transportation industry has played an important role in the Korean economy. The Korean maritime freight transportation industry is faced with a period of transforming it competitively and efficiently in this global age. This paper, therefore, aims to identify the impact of the maritime freight transportation industry in the Korean national economy. Hence, this paper provides policy-makers with accessible and reliable information regarding the role of the Korean maritime freight transportation industry. This study employs input-output (I-O) analysis to examine the role of the maritime freight transportation industry in the national economy for the period 1995-2003, with specific application to Korea. This study pays particular attention to the maritime freight transportation industry by taking the industry as exogenous variable and then investigates its economic impacts. We identify inter-industry linkage effects in 20 sectors, production-inducing effects, added value-inducing effects, and supply-shortage effects of the maritime freight transportation industry.

An electrical power distribution network is expected to deliver uninterrupted power supply to the customers. The disruption in power supply occurs whenever there is a fault in the system. Therefore, fast fault detection and its precise location are necessary to restore the power supply. Several techniques are proposed in the past for fault location in distribution network but they have limitations as their fault location accuracy depends on system conditions. The purpose of this paper is to present a travelling wave-based fault location method, which is fast, accurate and independent of system conditions.

This paper proposes an effective method for fault detection, classification and location using wavelet analysis of travelling waves for a multilateral distribution network embedded with distributed generation (DG) and electric vehicle (EV) charging load. The wavelet energy entropy (WEE) is used for fault detection and classification purpose, and wavelet modulus maxima (WMM) of aerial mode component is used for faulted lateral identification and exact fault location.

The proposed method effectively detects and classifies the faults, and accurately determines the exact fault location in a multilateral distribution network. It is also found that the proposed method is robust and its accuracy is not affected by the presence of distributed generation and electric vehicle charging load in the system.

Travelling wave based method for fault location is implemented for a multilateral distribution network containing distributed generation and electric vehicle load. For the first time, a fault location method is tested in the presence of EV charging load in distribution network.

Multilevel inverters play a major role in the development of high-power industrial applications. In traditional low-level inverters (e.g. 2-level), the switching frequency is restricted and the harmonic spectrum of the system is hard to meet power requirements. Similarly, high-level inverters consist of a large number of switches, complex modulation techniques and complex hardware architecture, which results in high power loss and a significant amount of harmonic distortion. Furthermore, it is a must to ensure that every switch experiences the same stress of voltage and current. The purpose of this paper is to present an inverter topology with lower conduction and switching losses via reduced number of switches and equal voltage source-sharing technique.

Herein, the authors present a cascaded multilevel inverter having less power switches, a simple modulation technique and an equal voltage source-sharing phenomenon implementation.

The modulation technique becomes more complex when equal voltage source-sharing is to be implemented. In this study, a novel topology for the multilevel inverter with fewer switches, novel modulation technique, equal voltage source-sharing and Inductor-Capacitor-Inductor filter implementation is demonstrated to the reduce harmonic spectrum and power losses of the proposed system.

The nine-level inverter design is validated using software simulations and hardware prototype testing; the power losses of the proposed inverter design are elaborated and compared with the traditional approach.