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This paper aims to present and define a factor to assess the severity supported along transformer windings when the transformer is subjected to a transient voltage waveform due a switching operation of a vacuum circuit breaker (VCB). This factor is identified as time domain severity factor (TDSF).

Since each of switching waveforms depend on the electrical interaction between transformer and the VCB, it implies that each of those combinations is characterized by a TDSF. To obtain the TDSF implies to manage two different models of the transformer under consideration. Firstly, a terminal model (black box model) of the transformer is built to compute the switching waveform at transformer terminals during VCB operation. Then, a detailed model (white box model) of the transformer is used to compute the internal transient voltage distribution along transformer windings.

A practical application of a power system consisting of a real transformer connected to a VCB is performed to show the sensibility of the TDSF coefficient.

Previous works found in the literature already consider the evaluation of the overvoltages in transformer associated to switching transient by coefficients, such as the frequency domain severity factor (FDSF). But this factor, as a global coefficient, could not assess the severity along windings to localize dielectrically weak points. Therefore, this paper overcomes this limitation proposing an alternative coefficient identified as time domain severity factor (TDSF).

Auxiliary power system is an indispensable part of the train; the auxiliary systems of both electric locomotives and EMUs mainly are powered by one of the two ways, which are either from auxiliary windings of traction transformers or from DC-link voltage of traction converters. Powered by DC-link voltage of traction converters, the auxiliary systems were maintained of uninterruptable power supply with energy from electric braking. Meanwhile, powered by traction transformers, the auxiliary systems were always out of power while passing the neutral section of power supply grid and control system is powered by battery at this time.

Uninterrupted power supply of auxiliary power system powered by auxiliary winding of traction transformer was studied. Failure reasons why previous solutions cannot be realized are analyzed. An uninterruptable power supply scheme for the auxiliary systems powered by auxiliary windings of traction transformers is proposed in this paper. The validity of the proposed scheme is verified by simulation and experimental results and on-site operation of an upgraded HXD3C type locomotive. This scheme is attractive for upgrading practical locomotives with the auxiliary systems powered by auxiliary windings of traction transformers.

This scheme regenerates braking power supplied to auxiliary windings of traction transformers while a locomotive runs in the neutral section of the power supply grid. Control objectives of uninterrupted power supply technology are proposed, which are no overvoltage, no overcurrent and uninterrupted power supply.

The control strategies of the scheme ensure both overvoltage free and inrush current free when a locomotive enters or leaves the neutral section. Furthermore, this scheme is cost low by employing updated control strategy of software and add both the two current sensors and two connection wires of hardware.

This paper deals with the three‐dimensional modeling of massive conductors carrying a total imposed current and involving multiply connected regions. Both stationary motion and time harmonic eddy current problems are considered. The aim of the modeling is to determine the current distribution and the eddy current’s effects inside the conductor, as well as to calculate the Lorentz force acting on a conducting region. The choice of a suitable formulation based on solving the current vector potential T and the magnetic scalar potential φ is argued, then various methods for the restoration of the Ampere law in the multiply connected regions are presented. Two methods for calculating an auxiliary vector potential T₀ are applied in order to calculate the force acting on the armature of a railgun and the repulsion between the electrodes of a vacuum circuit breaker, then the results are compared.

This paper aims to present an alternative practical framework to classify the skill and knowledge of the individual trainees by comparing it with the expert in an organization. This framework gives the benefit to the organization in order to know the ability level of the personnel and to be able to provide the personnel development method both in academic learning and workplace learning.

This research develops the framework based on relevant methodologies. Competency-Based Development is applied to investigate the knowledge and skill of the specific task. Knowledge Engineering is used to capture the experiences and construct knowledge model from relevance parties. Capability Maturity Model is then adapted to develop the capability and maturity level of the personnel. It can then be used to cluster the knowledge and skill. Finally, the Substation Maintenance Department of Provincial Electricity Authority (PEA), Thailand, is selected as a case study to test the proposed framework.

The results have shown that the proposed framework can be utilized to identify the capability level of the individual personnel. Furthermore, the appropriate maturity development of the employees in each level can also be identified. This proposed framework provides better results when comparing to the current PEA competency model, as the criteria in this framework are systematically derived from experts rather than relying solely on the proficiency level. Although, this framework was tested with the switchgear maintenance task, the results and its systematic approach have indicated that it can also be used to develop the capability maturity model for other fields of work.

The main originality of this research is the proposed competency analysis table, which integrates human resource development with knowledge management, risks management and management information system. Rather than performing these tasks separately for continuous quality improvement, organization can practically plan and perform the quality improvement-related tasks spontaneously. Moreover, the application of the capability maturity model to classify knowledge and skill of the maintenance tasks into maturity level is another academic value presented in this paper. The proposed framework gives the benefit to organization to classify the capability of the personnel. This is potentially beneficial to the human resource development personnel than traditional methods in the sense that it provides the information on how to develop the specific skill of the employees.

Sparkers can be used for the production of acoustic pulses as seismic source for sub‐bottom profiling in the sea. A multi‐tip (200‐800 tips) sparker has been developed, which makes high‐resolution seismic profiling possible in deep water. The characteristics of the multi‐tip sparker system have been measured in a basin in the laboratory using different arrangements of the capacitive energy storage and salinity of the water. A model in Matlab is used to calculate the current waveform in the spark array for different layouts of the power supply.

The purpose of this paper is to explain the process by which El Sewedy Company in Egypt decided to expand internationally by examining several modes of entry and choosing the best choice to expand in Russia and Kazakhstan.

The authors did several market analyses for each company to discover the external and internal environments. In addition, they weighted the advantages and disadvantages of each mode of entry to decide on the best mode to enter Russia and Kazakhstan.

The results confirm that the expansion for El Sewedy is challenging whether in Russia or Kazakhstan. Currently, El Sewedy's strategy is to deal through distributors to minimize risk; these distributors are mostly working in Kazakhstan given their easy connections and access there. The best solution for El Sewedy to expand is to trade high voltage and medium voltage cables in Kazakhstan as well as the trade of high voltage cables in Russia. Whether it is trading, exporting or a joint venture, El Sewedy's intentions are clear in its willingness to access the Russian and Kazakhstani markets, due to their richness and most of all their location as a central trade area in the region.

The comparison between Russia and Kazakhstan may appear very similar since both countries share almost the same circumstances and environment. Therefore, some of the information may be repeated twice to analyze both countries.

The results of this case study ensure the importance of analyzing the different modes of entry and doing a cost‐benefit analysis before deciding on how to expand in foreign market. Since circumstances and environments vary between markets, it is crucial to know all the details of the country in order to succeed in expanding in this foreign market.

This study explains a common case that happens in Egypt and every country whenever a company decides to expand. Usually, a company prefers a certain mode of entry over the other, but what is necessary is to follow what El Sewedy did, which is to evaluate all alternatives equally then decide on the best choice.

Donald Stokes’ approach to map the names of prominent scientists onto adiagram showing their impact on fundamental science and applied science is adopted and expanded to illustrate the dynamic interactions of the four nodes of the Cyclic Innovation Model (CIM). Tagging names of prototypical role models onto the four nodes and cycles of CIM increases the meta-level understanding of the fundamental concepts depicted by this innovation model. It also serves as a tool to validate the completeness of the model.

The case provides valuable insights on challenges faced by otherwise-protected organisations which are made to face the global onslaught. What happens to an organisation when its own collaborators become competitors overnight? What happens when market leaders refuse to share their technology or dictate their own terms? In addition, this case study looks at the strategy of diversification desired in the business portfolio and the cost of non-diversifications. The case evaluates the environment in which a capital-intensive industry has to operate. It evaluates the combination of all the variables required for undertaking a comprehensive analysis and aims at identifying the best possible level to which the business can be expanded to maximise profits under the known constraints in which the business has to operate.

Target audience is corporate executives, students of MBA/postgraduate programme in management in strategic management and/or workshops for understanding the concept of SWOT (strengths, weaknesses, opportunities and threats) analysis, competitor analysis, Porter's Five Forces Model, Boston Consulting Group (BCG) Matrix, business environment analysis and growth strategies for future.

A combination of global competition and open access in the domestic market is putting pressure on the margins, as new players are likely to move towards gaining market share by bidding aggressively. This is threatening the competitive intensity for Bharat Heavy Electricals Limited (BHEL) in the long-term. Raw materials, such as steel products, that are critical to production process are subject to substantial pricing cyclicality and periodic shortages of supply in India. The margins are thus continuously being impacted by movement in raw material prices, especially steel and copper. How BHEL hopes to sustain its growth story? Whether Chinese competition will kill BHEL? These are some of the pertinent questions the authors will try to answer in this case study.

Use of SWOT analysis to identify the strengths, weaknesses, opportunities and threats to a company and use it as a tool to strategic decision-making. Highlighting the importance of strategic tools such as Porter Model and BCG Matrix within an emerging economy backdrop; to illustrate the alternatives and difficulties/complexities involved in a strategic planning process of growth and cost cutting; and to analyse the financial statements of BHEL.

Analysing public sector undertakings (PSUs)/government companies involved in infrastructure build up/projects of strategic nature in the country, their performance, challenges and efficiency in pre-liberalisation era and post-liberalisation era, and identifying how many are visible today, including the reasons for their growth/decline in generating revenues and profits, has multiple social implications especially for an emerging economy like India. A look at the performance trends of such companies over the past years too would help them in their quest by assisting them to get an idea of business and the industry profile in which BHEL is operating.

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The purpose of this paper is to present an algorithm of the optimization of the dynamic parameters of an electromagnetic linear actuator operating in error‐actuated control system.

The elaborated “unaided” software consists of two main parts: optimization solver and numerical model of the actuator. Genetic algorithm has been used for optimization. The coupled field‐circuit‐mechanical model for the simulation of the system dynamics has been applied. Different optimization problems have been considered. The shape of the steady‐state force‐displacement actuator characteristic has been imposed and its deviation has been minimised. Next, the total operation time of the actuator without feedback, and the setup time of the actuator with feedback are minimised. Finally, required trajectory of movement has been imposed and trajectory error is minimised.

The elaborated algorithm and the computer code can be an effective tool for field‐circuit simulation of the dynamics of an electromagnetic linear actuator that operates in an automatic control system. It enables optimal design of the electromechanical system in respect to its dynamic properties.

The elaborated algorithm and the computer code presented in this paper can be an effective tool for the field‐circuit simulation of the dynamics of an electromagnetic linear actuator that operates in an automation control system.

The paper seeks to present an algorithm for a dynamical field‐circuit coupled simulation of an electromagnetic linear actuator operating in automated control systems.

The mathematical model includes: a transient electromagnetic field formulation for a non‐linear conducting and moving medium, equations which describe the electric circuits of the converter and the supply system, the equation of mechanical motion, the equation describing closed‐loop control and models for the sensor and the PID controller. The numerical implementation is based on the finite element method and the step‐by‐step algorithm for time discretization. In order to account for the nonlinearity of the ferromagnetic core the Newton‐Raphson procedure has been applied. The influence of the PID controller settings on the operation of the controlled actuator is shown. Dynamic disturbances, e.g. step change of the set value of mover position or change of loading force, have been analyzed.

The elaborated algorithm and the computer code can be an effective tool for field‐circuit simulation of the dynamics of an electromagnetic linear actuator operating in an automatic control system. Only tapered plunger should be used as multi‐stable actuators.

The study provides information of value in electromagnetic research.