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Applies the field/circuit two‐dimensional method and improved circuit method to engineering designs of the induction motor with stator cores made of amorphous iron. Exploiting of these methods makes possible computation of many different specific parameters and working curves in steady states for the “high efficiency” three‐phase small induction motor. Compares the results of this calculation with the results obtained for the classical induction motor with identical geometric structure.

To investigate the use of amorphous iron as the stator core material to increase the efficiency of electric machines in serialised production.

In the design process of a new structure for the induction motor with a stator core made from amorphous iron it is necessary to apply the circuit method and the field‐circuit method. The use of the circuit method allows quick calculations of many versions of the designed motor, but the use of the field‐circuit method is necessary for verification of the maximal value of the flux density in the entire area of the cross‐sections of the motor core.

A new construction for the small induction motor with the stator core made from amorphous iron was designed based on the classical structure of the four‐pole induction motor. In the designed motor a decrease of the electric energy costs was observed, which is much bigger than the material costs, and in effect lower total costs for the designed motor were obtained.

According to necessary changes in the motor construction, due to lower saturation limit for this material, the authors obtained a significant increase in the motor efficiency and a decrease in the total cost of the motor. The development of a new technology allows the cutting of amorphous magnetic materials and the production of electric motors from them.

This paper shows the possibility of using amorphous magnetic materials for stator core of small induction machines and the advantages of such construction for obtaining more efficient motor construction.

The purpose of this study is to review and summarise the existing available literature on lightweight cladding systems to provide detailed information on fire behaviour (ignitibility, heat release rate and smoke toxicity) and various test method protocols. Additionally, the paper discusses the challenges and provides updated knowledge and recommendation on selective-fire mechanisms such as rapid-fire spread, air cavity and fire re-entry behaviours due to dripping and melting of lightweight composite claddings.

A comprehensive literature review on fire behaviour, fire hazard and testing methods of lightweight composite claddings has been conducted in this research. In summarising all possible fire hazards, particular attention is given to the potential impact of toxicity of lightweight cladding fires. In addition, various criteria for fire performance evaluation of lightweight composite claddings are also highlighted. These evaluations are generally categorised as small-, intermediate- and large-scale test methods.

The major challenges of lightweight claddings are rapid fire spread, smoke production and toxicity and inconsistency in fire testing.

The review highlights the current challenges in cladding fire, smoke toxicity, testing system and regulation to provide some research recommendations to address the identified challenges.

Circular economy (CE) has gained considerable attention from researchers and practitioners over the past few years because of its potential social and environmental benefits. However, limited attention has been given in the literature to explore the drivers and barriers in CE implementation in emerging and developing countries besides China. Therefore, the purpose of this paper is to identify the drivers and barriers to implementing a CE in Pakistan’s automobile manufacturing industry.

This study adopts an explorative approach to understand the drivers and barriers at the micro-level CE implementation in Pakistan’s automobile industry. The research design includes both qualitative and quantitative methods using a survey instrument and interviews to gather data. The use of the two main sources of data provides the opportunity for triangulation of the data to improve the validity of the findings, and enables greater inferences from the results.

This study shows that “profitability/market share/benefit” (30 percent), “cost reduction” (22 percent) and “business principle/concern for environment/appreciation” (19 percent) are the top three drivers. Similarly, “unawareness” (22 percent), “cost and financial constraint” (20 percent) and “lack of expertise” (17 percent) are the top three barriers in implementing CE principles in Pakistan automobiles industry.

This study considers only Pakistan automobiles industry, and the practical implications potentially limit to emerging Asian economies.

This study is the first of its kind that has investigated the drivers and barriers of CE at the organizational level in the automobile industry of Pakistan. Thus, it helps to advance the understanding of the subject matter and enables the formulation of effective policies and business strategies by practitioners for upscaling CE and sustainability.

The purpose of this paper is to present the distribution of the magnetic field and additional losses analysis of the induction motors (IM) with opened and closed rotor slots.

In the field-circuit approach the distribution and changes of magnetic flux density in the motor are computed using a time-stepping finite element method. The additional losses in each element are evaluated at different frequencies.

An approximate analytical formulation is derived for rapid losses computation confirmed by the results of field-circuit method. For high-voltage motors due to the size ratios of the core and relatively deep stator and rotor slots major role in causing loss of higher harmonics play a fundamental slot harmonics. Higher harmonics order bigger than 100 cause only small part of total higher harmonics core losses. Closed rotor slots construction influenced significantly on no-load losses mainly due to reduction of losses at slot upper part. For nominal load condition that influence is not so strong according to the saturation of slot tips by rotor leakage flux. Nevertheless, core losses at load are several times higher as at no-load.

In future research authors will take into account motors feed from PWM inverter, working in the frequency range up to 400 Hz.

The results of investigation will be used in more detailed design of IMs especially for motors with closed rotor slots.

The methods presented in the paper was not used before. Also results of additional losses in the motor core calculation, especially according motors with closed slots at no load and load conditions are new.

The purpose of this paper is to quantitatively assess wood pallet suppliers' reaction to online reverse auctions and its impact on their business policies and practices.

Survey method was used to determine how pallet suppliers react to online reverse auctions.

Determines that pallet suppliers do not realize the benefits claimed by online reverse auction service providers. Identifies new sources of costs which accrue to buyers and are not accounted for in so‐called “total cost” request for quotes including: retaliatory pricing practices, less cooperative relationships, and sourcing work back to the original supplier. The qualitative benefits identified for suppliers by third‐party online reverse auction service providers are overstated or false.

The present work can be extended to other commodity categories to identify similarities and differences in how suppliers react to online reverse auctions, understand the domain of successful and unsuccessful application of the online reverse auction tool, and provide further insight into the evolution of buyer‐seller relationships, including embedded organizational routines such as power‐based bargaining.

Findings mirror the results found in a previous study that examined aerospace parts suppliers' reaction to online reverse auctions, and indicates that market makers have consistently overstated the benefits of online reverse auctions to both sellers and buyers, and the use of this tool will typically result in unfavorable outcomes for both buyers and sellers.

This paper will be of interest to buyers, sellers, and market makers, as it identifies important problems with online reverse auctions, and suggests questions that buyers should ask market makers to ensure better sourcing decisions.

This study aims to examine travel patterns and factors that explain children’s use of green space for outdoor learning. This knowledge will be valuable for urban planners and policymakers to plan, design, develop and maintain green spaces that consider children’s interests.

The analysis consists of three steps. First, this paper performed a mapping analysis to explain the accessibility and services of green spaces in supporting children’s education. Second, using data from a survey distributed to school teachers, this paper explored factors affecting trip frequency, travel distance and walking when visiting green spaces. Third, this paper interviewed teachers and conducted observations and conversations with children to gain additional insights.

The quantitative analyses found that size, path network linkages, path length, use for nature observation, play features, path density, walking and biking may influence children’s preference for using green spaces. This study identified five factors (playing, socialising, exploring, biodiversity and accessibility) that drive children to visit green spaces.

There is limited knowledge of the links between green space and children’s travel patterns and factors explaining the use of green spaces. To the ebst of the authors’ knowledge, this study seems to be the first attempt to introduce a mix of methods containing mapping, qualitative and quantitative analyses to explain children’s use towards green spaces.

The purpose of this paper is to focus on the influence of electromagnetic field during the arc discharge carbon nanotubes synthesis. It proposes modeling of electromagnetic field distribution to calculate forces in the area of arcing. The paper presents the influence of this field on the final product of the synthesis.

A short literature review of the arc discharge systems supported by electromagnetic field is presented. The technical solution of the coil placement is discussed. An experimental research is described. The research system constructed preceded by a series of measurements and modeling is analyzed.

The paper describes the significant meaning of the electromagnetic field during the synthesis. The electromagnetic field forces the slow rotation of the carbon plasma column where carbon nanotubes are formed. It leads to the improvement in yield.

Because the research is limited to one type of geometry of the reactor, the results may vary in different reactors. However, the influence of the electromagnetic field is confirmed. Therefore, researchers are encouraged to investigate the influence of the electromagnetic coil in the applied systems.

The systems with a coil inside the reactor require the application of complex cooling systems or/and additional screens. The work proposes a technical solution based on the coil placed outside the reactor. Therefore, it simplifies the construction and increases the yield.

The high yield of the high-quality nanotubes opens new technical possibilities for electronics and electrical engineering.

The paper identifies a connection between the electromagnetic field, the arc discharge movement, plasma jet, carbon nanotubes containing deposit and the yield.

The purpose of the paper is to explore the benefits of online reverse auctions for both buyers and suppliers in contrast to the negative implications for procurement process. This paper also aims to provide a framework for managers determining if participation in online reverse auctions is appropriate for their business.

Information was gathered from numerous sources including surveys from both buyers and suppliers in a multitude of industries in order to create a comprehensive analysis of benefits and shortcomings of online reverse auctions. Additional research could be pursued by conducting a detailed cost analysis of buyers who have adopted online reverse auctions. A thorough analysis of unit cost and total cost changes amongst various industries could provide benchmark data for companies contemplating entering the reverse auction arena.

The research analysis finds a strong temptation for buyers to participate in online reverse auctions: price reductions. However, buyers should approach online reverse auctions with caution as total cost savings can be misleading and participation may result in damaged relationships with suppliers. This can be seen in the results portrayed in the buyer and supplier industry survey which shows that buyers are more keen to participate in online reverse auctions in order to gain advantage of the lower prices and global potential of suppliers, whereas some buyers are keen on making a strong relationship with existing suppliers through direct contact.

Buyers' determination to use online reverse auctions relies on product specifications, supplier relationships, the current supply and demand environment, indirect costs, and several other factors which will vary for each product and for each buyer. Therefore, an all‐encompassing decision model cannot be presented to accommodate each scenario. However it can be seen that the industrial survey to the buyers and the suppliers has been an effective tool in bridging the gap between the decision model and the factors that vary between each buyer.

This paper provides managers a framework for determining if online reverse auctions are appropriate for their business. In practice, additional company specific information can be applied to the decision making model.

This paper includes a comprehensive decision framework specifically for buyers as well as an abbreviated decision model for suppliers.

Examines if online reverse auctions are consistent with the Caux Round Table Principles for Business. Identifies numerous contradictions that contribute to the perpetuation of divisive business practices. Concludes that buyer behaviors must evolve from focusing on short‐term tactics designed to reduce purchase price and instead pursue collaborative cost reduction practices with key suppliers.