Search results

The purpose of this paper is twofold. The first is to examine in detail energy efficiency performance of German and Colombian food industries. The second is to explain the factors that have influenced energy efficiency.

Using data at the three‐digit level of aggregation, the paper compares energy efficiency across sectors of the food industry for the period 1998‐2005. Energy efficiency is analysed using the energy intensity (EI) indicator as well as a decomposition analysis. To determine the factors that have influenced energy efficiency performance, the concept of the production function is used.

The results show that both countries' food industries improved energy efficiency. During the period of study, energy consumption in the German food industry increased by an average of 1.3 per cent per year and the EI decreased 7 per cent, whereas the Colombian food industry decreased its energy consumption by an average of 1.9 per cent per the year and the EI decreased 11 per cent. However, the Colombian food industry needs 2.2 times more energy than the German food industry to produce a unit of gross production. A decomposition analysis indicated that economic and technical factors have played an important role in the energy efficiency performance because increases in economic growth and technology improvements increase the industrial sector's ability to improve energy efficiency. A second‐stage empirical analysis reveals that capital, material, investments and value‐added variables had a positive influence on energy efficiency performance in both countries. Energy prices are shown to have a positive influence on energy efficiency in the German food industry, whereas the sizes of enterprises and concentration processes played an important role on energy efficiency performance in the Colombian food industry.

The literature indicates the relative lack of attention paid to the analysis of energy use across sectors of food industry as well as the lack of studies determining the factors that have affected energy consumption and energy efficiency performance using cross‐country and cross‐sectoral comparisons.

Many enterprises implement various business projects on the Internet in the global knowledge economy. The task of managing distributed and heterogeneous project knowledge is very important in increasing the knowledge assets of enterprises. Accordingly, this work presents a project‐based knowledge map system to properly organize project knowledge into topic maps, from which users can obtain in‐depth concepts to facilitate further project development. A two‐phase data mining approach involving the ISO/ISEC 13250 topic maps and Extensible Markup Language (XML) is used to establish the proposed system, which can determine knowledge patterns from previous projects and transform these patterns into a navigable knowledge map. The map can help users to locate required information and also offers subject‐related information easily and rapidly over the Internet.

“Social”, in terms of EC policy, covers areas from “youth” to health and safety. This, and the many non‐EC organisations involved in this field, means that any comprehensive overview of published material on the social dimension to Europe would fill a whole issue of Aslib Proceedings!

The S-MCSRM is a two-phase excited switched reluctance motor (SRM), with the short flux path and mutual inductance coupling, which is suitable for the oil submersible pump application owing to large torque and three-wire connection with the standard full-bridge power converter. However, there is not literature to disclose its model due to the complicated mutual inductance coupling. The FEM model is a time-consuming method to analyze this motor. For the first time, this paper aims to propose an S-MCSRM model for performance analysis and control method developing. The proposed model would save simulation time and be a theoretical fundamental for further implementing control algorithm.

The S-MCSRM's operating principle is analyzed, and the voltage equation and the generated torque are deduced. The FEM is utilized to obtain the five typical magnetization curves that describe the S-MCSRM's magnetic path characteristic. The magnetic co-energy equation, phase torque and total torque equations are obtained. From the basic voltage equation, the S-MCSRM's state space model is built for the dynamic analysis and control purpose. The S-MCSRM is widely analyzed in detail by using the proposed model and comparison with the conventional SRM. JMAG finite element package is used to verify the proposed model.

The proposed modeling method is validated by the identical results to those from FEM-based JMAG software. The proposed model just takes second-level time, which is far less than minute-level time consuming of FEM method. The S-MCSRM generates larger torque than the conventional SRM, with three-wire and standard full bridge power converter, and it is confirmed that the S-MCSRM is suitable for the oil submersible pump applications.

This paper proposes a new modeling method for the S-MCSRM to exactly analyze the motor's operating performances, and also it is a theoretical fundamental for developing control algorithm. The proposed model saves much time in analysis, calculation, and simulation, when compared to the FEM method. The completed analysis including flux linkages, torque, torque-ripple, and torque-speed characteristic discloses the S-MCSRM's steady-state operating performances, which provides the deep insight for this kind of motor's applications.

This paper seeks to propose a novel bearingless switched reluctance motor (BSRM).

The operating principle and structure characteristics of the proposed three‐phase 12/8‐pole BSRM is analyzed in detail. Finite element method‐based calculations are applied to a prototype and some important characteristics are obtained, including radial force, static torque, air‐gap magnetic flux density, and effect of control winding current on the torque, where magnetic saturation is taken into account by using a nonlinear B‐H curve.

On the basis of the simulated results, it can be concluded that the proposed BSRM presents an excellent performance in the suspending force and in the torque. The analyzed results show that the two control‐winding currents can effectively control the radial suspending forces and produce negligible effect on the motor torque, which is mainly produced by the main‐winding currents.

In this paper, a novel BSRM is proposed. Instead of the six sets of radial suspending control windings required by conventional three‐phases BSRM, the proposed structure requires only two sets of suspending control windings, regardless of the phase number, leading to a simpler power converter with less power switches, thus lowering the overall system cost.

The purpose of this paper is to propose a new three-phase switched reluctance motor (SRM), and achieve high-torque and low-cost. This new SRM's winding configuration uses the double-layer distributed windings, which is different from the conventional SRM's single tooth coils.

The operating principle of new SRM is analyzed, and the voltage equation and the generated torque are deduced. Finite element method (FEM) and finite element circuit coupled method are utilized to evaluate the new motor's operating performances. The two dimensional (2D) frequency response analysis model is employed in the FEM model. Based on the 2D frequency response analysis model, the magnetic field distribution, self-inductance, and mutual-inductance for the new SRM are analyzed in detail. A co-simulation model using FE analysis package and Matlab-Simulink is proposed to simulate the new SRM drive. The simulated and experimental results verify the new SRM.

For the new SRM with double-layer distributed windings, a co-simulation method is proposed to analyze its characteristics. The new SRM presents lower torque ripple coefficient and generates larger torque than the conventional SRM, with three-wire and standard full bridge power converter, rather than six-wire and asymmetric half-bridge converter for conventional SRM.

This paper proposes a new SRM with the double-layer distributed windings driven by a standard full bridge inverter. In order to calculate dynamic characteristics of the new SRM, a co-simulation method using FEM and Simulink is proposed to simulate the new SRM drive, where the power inverter and the current chopping control algorithm are implemented.

Welded components are often subjected to variable amplitude service loads, increasing the uncertainty of fatigue life due to material strength, notch geometries, defect content and residual stresses. In the case of friction stir welding (FSW) of aluminium alloys no data were found available concerning fatigue behaviour under variable amplitude loading. The purpose of this paper is to determine the fatigue strength of friction stir welds in AA6082‐T6 under constant and variable amplitude loading and analyse the validity of Miner's rule for these specific welding conditions.

Fatigue tests were carried out in a servo‐hydraulic testing machine using a stress ratio of R=0. Typified Gassner amplitude spectra were considered, using four shape exponent values. Microhardness tests were performed to characterize the Vickers hardness profile in the vicinity of the weld area. Relatively to the base material (BM), the FSW process leads to a decrease of the static mechanical properties.

Detailed examination revealed a hardness decrease in the thermo‐mechanically affected zone and the nugget zone average hardness was found to be lower than the base alloy hardness. The comparison with data collected from the literature shows that FSW specimens present higher fatigue resistance than specimens welded by metal inert gas and tungsten inert gas processes. However, they still have lower fatigue lives than the BM. Using the equivalent stress calculated by Miner's rule, a good agreement was observed between constant and variable fatigue loading results. The characteristic curve obtained for friction stir welds is higher than the International Institute of Welding (IIW) fatigue class for fusion welds with full‐penetration both‐sided butt joints.

No data are available concerning fatigue behaviour under variable amplitude loading for friction stir welds of aluminium alloys. Furthermore, this paper analyses the fatigue strength of friction stir welds in AA6082‐T6 under constant and variable amplitude loading in order to verify the validity of Miner's rule for this specific welding process. A comparison between characteristic fatigue curves, using IIW fatigue classes (FAT), is also performed.

The purpose of this paper is to examine institutional influences on the customer service (CS) and complaints handling (CH) practices of the Australian Internet industry.

The study adopted a qualitative research methodology using semi-structured interview as a research method. The study was informed by constructivist/interpretive research paradigm approaches to knowledge. Eleven senior executives from key Internet industry stakeholder organizations were interviewed.

Using the neo-institutional theory lens, this study found that the institutional forces (regulatory, customer and competition pressures) played a pivotal role in bringing all Internet industry stakeholders together to address CS/CH shortcomings in the old Telecommunications Consumer Protection (TCP) Code 2007. This led to significant changes to the CS/CH practices detailed in the revised TCP Code 2012. The study findings revealed that frequent and fateful collaborations between central institutional actors have led to the emergence of organizational fields. The actors identified in the emerging organizational fields actively influence the CS/CH practices and the subsequent implementation of the practices in vLISPs.

The study focused on the functional aspects of service quality (SQ). Technical aspects of SQ is equally important, and future research needs to consider both aspects of SQ when assessing overall performance of vLISPs.

The study findings encourage vLISP managers to continue collaboration with external stakeholders and develop customer-friendly practices that deliver desirable CS/CH outcomes.

The study findings revealed that when all vLISP industry stakeholders collaborate with each other on a focal issue, there is noticeable progress towards development of CS practices that will contribute to a better CS experience.

An evidence-based approach was used towards understanding and explaining how and why institutional actors of technology-based service organizations act together. A significant contribution arising from this study is the identification and discussion of emerging organizational fields comprising the central actors in the Internet industry. These emerging organizational fields have the potential to develop into mature organizational fields and inform future CS/CH practices and consumer protection policies in the Australian Internet industry.

The purpose of the article is to develop an innovative pedagogic tool: an escape room board game to be played in-class, targeting an introduction to an ethics course for engineering students. The design is student-centred and aims to increase students' appreciation, commitment and motivation to learning ethics, a challenging endeavour for many technological students.

The methodology included the design, development and in-class application of the mentioned game. After application, perception data from students were collected with pre- and post-action questionnaire, using a quasi-experimental method.

The results allow to conclude that the developed game persuaded students be in class in an active way. The game mobilizes body and mind to the learning process with many associated advantages to foster students' motivation, curiosity, interest, commitment and the need for individual reflection after information search.

The main limitation of the game is its applicability to large classes (it has been successfully tested with a maximum of 65 students playing simultaneously in the same room).

The originalities and contributions include the presented game that helped to captivate students to ethics area, a serious problem felt by educators and researchers in this area. This study will be useful to educators of ethics in engineering and will motivate to design tools for a similar pedagogical approach, even more so in areas where students are not especially motivated. The developed tool is available from the authors at no expense.

Indian government initiated several skill development policies and different types of vocational education and training (VET). Yet the participation in skill education is low because of poor labour market outcomes. This paper aims to calculate returns to skill education to understand the type of training that will have better labour market outcomes.

In this paper nationally representative data from the periodic labour force survey (PLFS), collected by the national sample survey office for 2017–2018, are used to estimate the returns to formal and non-formal VET obtained (after different levels of general education) with the help of Heckman's two-stage method.

Nearly 8% of the working-age population has received some form of VET (mostly non-formal), generating poor returns. For the overall population, formal on-job training (OJT) and full-time VET influence wage positively and significantly. Full-time VET obtained after secondary and below levels of education generates positive returns, whereas part-time VET is profitable only to those without formal education. At the graduate level, technical education obtained along with VET is associated with better wages.

In India where a considerable proportion of the workforce is employed in the informal sector, different types of skill training like full-time, part-time and OJT influence labour market outcomes. This finding has policy implication for countries with large informal sector and calls for further research in such countries.