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The large size of models and long computing time prevent the creation of full‐scale, three‐dimensional models of end region of turbogenerators. Only exact three‐dimensional model can illustrate complex phenomena of end region losses. Also some methods of decreasing such losses cannot be simulated in two‐dimensional models. The purpose of this paper is to focus on a method of creating three‐dimensional models of turbogenerators' end regions for calculations of eddy current losses.

Time‐stepping is the most expensive part of computation. A harmonic model would be free from that disadvantage and it can provide a tool to make an accurate, fully three‐dimensional model of a steady state for different loads and provide results in a reasonable time.

The research focuses on the method of creating three‐dimensional models of turbogenerators end region for calculations of eddy current losses. By using two‐dimensional, time‐stepping models and empirical loss functions for a main flux and three‐dimensional models for eddy current losses from a perpendicular flux of an end connections, it is found that fast analysis of that complex part of a machine can be achieved.

The approach proposed in the paper is a universal and novel method of calculation losses of turbogenerators' end regions. Combining two‐dimensional and three‐dimensional models provides advantages of both known methods: fast computation time from simplified models and good representation of complex geometry of a machine.

A transport model has been developed which is reasonably accurate, and has proven quite efficient for the two‐dimensional numerical simulation of submicron‐scale Si and GaAs devices. In this model an approximate form of the energy‐transport equation is developed; this equation is easily included in otherwise‐conventional device simulation codes, which then require only slightly more solution time than standard models using field‐dependent transport coefficients. Calculations for 0.25 micron gate length Si and GaAs MESFET's show that velocity overshoot effects can be very important, particularly in the latter material; predicted saturation currents in the GaAs devices are almost three times larger than those that would have been predicted using conventional transport models. The model described, and its application in simulation programs, should find use in the design of submicron‐scale devices to properly take advantage of overshoot phenomena.

The paper presents a two‐dimensional and three‐dimensional thermal model of the power hybrid circuit. Measurement of the accuracy of temperature computation using the two‐dimensional model is carried out. Based on both models, the AUTO_T program for thermal analysis is created. This program chooses the proper model according to the required accuracy of computation. The reduction of the computational time is evident.

The purpose of this study is to propose a simplifying approach for modelling a reliability test. Modelling the reliability tests of printed circuit board (PCB)/microelectronic component assemblies requires the adoption of several simplifying assumptions. This study introduces and validates simplified assumptions for modeling a four-point bend test on a PCB/wafer-level chip scale packaging assembly.

In this study, simplifying assumptions were used. These involved substituting dynamic imposed displacement loading with an equivalent static loading, replacing the spherical shape of the interconnections with simplified shapes (cylindrical and cubic) and transitioning from a three-dimensional modelling approach to an equivalent two-dimensional model. The validity of these simplifications was confirmed through both quantitative and qualitative comparisons of the numerical results obtained. The maximum principal plastic strain in the solder balls and copper pads served as the criteria for comparison.

The simplified hypotheses were validated through quantitative and qualitative comparisons of the results from various models. Consequently, it was determined that the replacement of dynamic loading with equivalent static loading had no significant impact on the results. Similarly, substituting the spherical shape of interconnections with an equivalent shape and transitioning from a three-dimensional approach to a two-dimensional one did not substantially affect the precision of the obtained results.

This study serves as a valuable resource for researchers seeking to model accelerated reliability tests, particularly in the context of four-point bending tests. The results obtained in this study will assist other researchers in streamlining their numerical models, thereby reducing calculation costs through the utilization of the simplified hypotheses introduced and validated herein.

In the present study, a finite volume approach for solving two‐dimensional, two‐fluids flows with heat and mass transfer was developed for predicting the flow of particulate materials through pneumatic dryer. The model was solved for a two‐dimensional steady‐state condition and considering axial and radial profiles for the flow variables. A two‐stage drying process was implemented. The numerical procedure includes discretization of calculation domain into torus‐shaped final volumes, solving the gas phase conservation equations by a modified semi‐implicit method for pressure‐linked equations algorithm, and the conservation equations of particulate phase were solved by the explicit forward difference algorithm. The mass momentum and energy coupling between the phases were considered by principles of the Interphase slip algorithm. In order to validate the theoretical and the numerical models, the developed models were applied to simulate the drying process of wet PVC particles in a large‐scale pneumatic dryer and to the drying process of wet sand in a laboratory‐scale pneumatic dryer. The predictions of the numerical simulations were compared successfully with the results of independent numerical and experimental investigations. Following the models validation, the two‐dimensional distributions of the flow characteristics were examined.

This paper aims to develop a parsimonious and innovative model that captures the dynamics of new product diffusion in the recent high-technology markets and thus assist both academicians and practitioners who are eager to understand the diffusion phenomena. Accordingly, this study develops a novel diffusion model to forecast the demand by centering on the dynamic state of the product’s adoption rate. The proposed study also integrates the consumer’s psychological point of view on price change and goodwill of the innovation in the diffusion process.

In this study, a two-dimensional distribution function has been derived using Cobb–Douglas’s production function to combine the effect of price change and continuation time (goodwill) of the technology in the market. Focused on the realistic scenario of sales growth, the model also assimilates the time-to-time variation in the adoption rate (hazard rate) of the innovation owing to companies changing marketing and pricing strategies. The time-instance upon which the adoption rate alters is termed as change-point.

For validation purpose, the developed model is fitted on the actual sales and price data set of dynamic random access memory (DRAM) semiconductors, liquid crystal display (LCD) monitors and room air-conditioners using non-linear least squares estimation procedure. The results indicate that the proposed model has better forecasting efficiency than the conventional diffusion models.

The developed model is intrinsically restricted to a single generation diffusion process. However, technological innovations appear in generations. Therefore, this study also yields additional plausible directions for future analysis by extending the diffusion process in a multi-generational environment.

This study aims to assist marketing managers in determining the long-term performance of the technology innovation and examine the influence of fluctuating price on product demand. Besides, it also incorporates the dynamic tendency of adoption rate in modeling the diffusion process of technological innovations. This will support the managers in understanding the practical implications of different marketing and promotional strategies on the adoption rate.

This is the first attempt to study the value-based diffusion model that includes key interactions between goodwill of the innovation, price dynamics and change-point for anticipating the sales behavior of technological products.

The purpose of this paper is to solve the diverse and complex problems of flat-knitting sports upper process design, improve the design ability of upper organization, and realize three-dimensional simulation function.

Firstly, the matrix is used to establish the corresponding pattern diagram and organizational diagram model, and the relationship between the two is established by color coding as a bridge to completed the transformation of the flat-knitted sports upper process design model. Secondly, the spatial coordinates of the loop type value points are obtained through the establishment of loop mesh model, the index of two-dimensional and three-dimensional models of uppers and the establishment of spatial transformation relationship. Finally, using Visual Studio as a development tool, use the C# language to implement this series of processes.

Digitizing the fabric into a matrix model, combined with matrix transformation, can quickly realize the design of the flat-knitting process. Taking the knitting diagram of the upper process as the starting point, the loop geometry model corresponding to the element information is established, and the three-dimensional simulation effect of the flat-knitted upper based on the loop structure is realized under the premise of ensuring that it can be knitted.

This paper proposes a design and modeling method for flat-knitted uppers. Taking the upper design process and 3D simulation effect as an example, the feasibility of the method is verified, which improves the efficiency of the development of the flat-knitted upper product and lays the foundation for the high-end customization of the flat-knitted upper.

Importance-performance analysis (IPA) is an effective tool for firms to prioritise service quality attributes, but has limitations in evaluating and enhancing service quality within a competitive environment. The purpose of this paper is to present an evolved model of IPA – importance-performance benchmark vectors (IPBV) – as a benchmarking tool and investigate its applicability in the context of hotel service quality.

Empirical studies based on self-completion survey data from 150 customers of two full-service hotels in Taiwan were conducted in to examine the practical utility of IPBV.

Eight key benchmark typologies were identified and expressed as vectors in the IPBV model which are as follows: “sustainable advantage”, “potential strength”, “false advantage or outstanding advantage”, “cease-fire competition”, “false disadvantage or on-hand disadvantage”, “potential weakness”, “dangerous warning” and “head-on competition”.

The paper extends the methodology to more cases, and other service industries to test further the discriminatory power of the model and to explore the descriptors in the IPBV vector model. Alternative seven-point or nine-point Likert scales could be explored to test the discriminant validity using means. The alternative IPA diagonal approach focussing on GAP analysis may reveal alternative interpretations for the IPBV vector model. Other extended models of IPA, which include competitor analysis, should be compared in practice using a data set where both quantitative and qualitative data could be generated.

The paper proposes the two-dimensional IPBV model which retains the advantages of IPA, but also includes competitor or benchmark comparisons which enable organisations to analyse their relative competitive position. The two-part model provides both quantitative information and qualitative interpretation of relativities. The graphical matrix models provide simple quantitative analysis of attributes, whilst the IPBV vector model provides qualitative interpretations of the eight competitive market positions. Vector analysis enables the development of competitive strategies relative to benchmarks, or within a competitive set. Importance is retained and means that organisations can benchmark against a range of competitors prioritising specific attributes for resource allocation.

The interpretive utility of the model should be explored with practitioners and decision makers in the service industries. The model has been designed for practical use in industry to inform operational and strategic decision making, its usefulness in practice should be explored and the attitudes of practitioners to the model should be tested.

Traditional approaches to benchmarking have adopted a one-dimensional approach that does not include a measure of the relative importance of the service quality dimensions in specific markets. This research develops a two-dimensional advanced model of IPA, called IPBV, which is based on vector relationships between key attributes of service quality. These vectors are explored and described in competitive terms and the model is discussed with regard to its implications for industry, practitioners and researchers.

In modeling an aircraft wing, structural idealizations are often employed in hand calculations to simplify the structural analysis. In real applications of structural design, analysis and optimization, finite element methods are used because of the complexity of the geometry, combined and complex loading conditions. The purpose of this paper is to give a comprehensive study on the effect of using different structural idealizations on the design, analysis and optimization of thin walled semi-monocoque wing structures in the preliminary design phase.

In the design part of the paper, wing structures are designed by employing two different structural idealizations that are typically used in the preliminary design phase. In the structural analysis part, finite element analysis of one of the designed wing configurations is performed using six different one and two dimensional finite element pairs which are typically used to model the sub-elements of semi-monocoque wing structures. Finally in the optimization part, wing structure is optimized for minimum weight by using finite element models which have the same six different finite element pairs used in the analysis phase.

Based on the results presented in the paper, it is concluded that with the simplified methods, preliminary sizing of the wing configurations can be performed with enough confidence as long as the simplified method based designs are also optimized iteratively, which is what is practiced in the design phase of this study.

This research aims at investigating the effect of using different one and two dimensional element pairs on the final analyzed and optimized configurations of the wing structure, and conclusions are inferred with regard to the sensitivity of the optimized wing configurations with respect to the choice of different element types in the finite element model.

The purpose of this paper, taking banking as the research object, is to build up a psychology covenant model for service enterprises and customers and to seek the form of the construction dimension in the psychology covenant between the service enterprise and the customer.

SPSS16.0 was used for the exploratory factor analysis and AMOS7.0 for the confirmatory factor analysis.

The psychological contract between service enterprises and customers is composed of two‐dimensional structures: the transactional psychological contract and the relational psychological contract.

The biggest limitation of this paper is the research region being limited to banking. Future research can extend to other industries.

The result has the theoretic reference to the tactic establishment for customer relationship management in China's service industry against the background of a transfer economy.