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I‐V characteristics of GaAs n‐i‐n structures are calculated by considering impact ionization of carriers. Impact ionization at reverse‐biased n‐i junction becomes a cause of steep current rise when an acceptor density in the i‐layer is high. It is shown that an optimum acceptor density exists to keep a good isolation. Photoconduction transients of GaAs n‐i‐n structures are also simulated, and are shown to be strongly affected by existence of n‐i junctions.

A numerical model of the inclined open thermosyphon has been developed using a finite difference algorithm to solve the vorticity vector potential form of the Navier‐Stokes equations. The model simulates flow in an inclined cylinder whose bottom end is sealed and whose top is connected to uniform temperature reservoir, a configuration typical of evacuated tubular solar absorbers. The solution domain includes the cylinder only without the reservoir; therefore a special set of boundary conditions has been derived for the vector potential at the top end which is a flow‐through surface. Steady flow is simulated at various combinations of Rayleigh number, aspect ratio and mode of heating. An experimental set‐up has also been developed in order to investigate the development of different flow patterns previously predicted by analytical and numerical workers, as well as to observe more closely the behaviour of the fluid at the orifice. Velocity profiles were measured at the orifice using laser doppler anemometry, and compared with predictions from the numerical model.

The purpose of the present study is to reveal the antecedents of the new green product success (NGPS) of small and medium-sized enterprises (SMEs) that manufacture in Türkiye with a middle-income economy. To this end, a research model for the serial mediating role of green human capital (GHC) and green adaptive ability (GAA) in the relationship between green mindfulness (GM) and NGPS was developed and tested. Determining the driving forces of NGPS is essential due to the contributions of SMEs manufacturing, especially in middle-income economies, such as Türkiye, to the national economy.

The present study used partial least squares structural equation modeling (PLS-SEM) to test the hypothesized relationships. The study hypotheses were tested in a sample of 396 manufacturing enterprises, qualified as SMEs in Türkiye with ISO 14001 certificates.

Empirical evidence indicates that GM, GHC and GAA act as significant antecedents of NGPS. Furthermore, empirical evidence demonstrates that GHC and GAA, in turn, mediate the relationship between GM and NGPS.

Managers, especially in manufacturing SMEs, should be aware that they need to develop intangible resources to improve NGPS. Increased investment in GM results in higher levels of GHC and GAA, which collectively leads to improved NGPS.

The current literature has not previously explained the mechanism of the relationship between GM and NGPS. The originality of the present study, which discusses the relevant research gap, is to develop an integrated framework to investigate how GM impacts NGPS, specifically for SMEs, and to test it empirically.

The purpose of this paper is to use numerical simulations to investigate the energy conversion performance and the flow and temperature structures inside horizontal tubes connected to a vertical manifold channel.

The simulations are performed for different flow rates and inlet temperatures using CFD.

In both the “flowing wind mode” and “upwind mode,” the inlet velocity is not infinitely small under the influence of natural convection; however, such small inlet velocities cannot be achieved in practice and are of no practical significance. In the “flowing wind mode,” the appropriate velocity for achieving high efficiency is 0.01-0.02 m/s. In the “upwind mode,” the appropriate velocity for obtaining high efficiency is 0.1-0.2 m/s. A high inlet temperature can lead to high efficiency; therefore, a large temperature difference and a small flow can be used in actual designs.

The energy conversion performance and flow structures inside evacuated tubular collectors were investigated using CFD for different operating conditions, notably in the “following wind mode” and the “upwind mode.”

A computer program for the solution of the single carrier semiconductor equations in GaAs has been developed to simulate charge storage and transfer in GaAs charge‐coupled devices. An uncoupled Newton method is used to solve the steady state problem, and a stable, uncoupled method is used for the transient solution. Using transient simulation, the transfer of a charge packet from well to well can be simulated over time. By comparing the size of the charge packet before and after the transfer, information on the charge transfer inefficency can be derived.

This paper investigates the impact of the PricewaterhouseCoopers (PwC) merger in Australia on existing and potential clients of the new merged firm. From prior theory it is expected that some existing clients may have an incentive to switch away from a newly merged firm as the same larger firm now audits close competitors once audited by separate firms. Prior theory also suggests that another group of potential clients should be attracted to the newly merged firm where the merger enhances or creates industry specializations. The expectation is that in both of these instances there will be increased switching activity associated with the newly merged audit firm. Contrary to expectations, a significantly lower level of switching behaviour was observed for the newly merged firm compared with that of the other Big 5 firms, suggesting that an advantage of enhanced specialization may not be the attraction of new clients but the retention of existing clients. When comparing the nature of the switches, some support was found for the view that the switches to the new firm were likely to be in enhanced areas of specialization, but no evidence was found to suggest that close competitors would switch away from this firm. The greater rate of retention of clients compared with other Big 5 firms was not associated with a more competitive audit pricing policy.

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 purpose of this paper is to examine an ongoing process of logic assimilation within an amateur sports organisation (ASO) called the Gaelic Athletic Association (GAA). It seeks to develop our understanding of how forms of accounting mitigated (or exacerbated) the tensions that arose among GAA members due to the consequences of the assimilation of select elements of a professional logic and a commercial logic within its traditionally dominant social welfare logic.

Interviews were undertaken with representatives and members of the GAA to understand the effects of growing commercialisation and professionalisation on the organisation’s traditional amateur status and social mission. In particular, the authors sought to understand how accounting, in the form of financial reporting, influenced the extent of the tensions that arose. Interviews were supported by an extensive collection of podcasts and news articles that discussed this topic.

The paper’s findings offer unique empirical insights into the role played by forms of accounting in the maintenance of amateurism within an ASO. It reveals the conflicting role of financial reporting within the GAA whereby it was used by the GAA’s management to ease member concerns surrounding logic assimilation while simultaneously being ignored by clubs and counties to facilitate payments to managers thereby eroding the amateur status of Gaelic Games.

The paper is unique in its exploration of logic assimilation within a form of hybrid organisation that has previously been unexamined in the accounting literature. It extends extant understandings of how accounting influences the co-existence of potentially conflicting logics. The paper also discusses the implications of what accounting makes visible and keeps invisible on the longevity of the traditionally dominant social welfare logic within an ASO.

A pseudo steady‐state model is developed to study heat transfer, fluid flow, and the interface shape in the liquid encapsulated vertical Bridgman crystal growth. The model, which is governed by momentum, heat, and overall mass balances in the system, is solved by a finite‐volume/Newton method. Flow and temperature fields, as well as unknown melt/crystal and melt/encapsulant interfaces, are calculated simultaneously. Sample calculations are mainly conducted for the GaAs/B₂O₃/PBN system. Calculated results for the Germanium/graphite system are compared with finite element calculations by Adornato and Brown, and they are in good agreement. The effects of some process parameters, including the growth speed, ambient temperature profile and heat transfer conditions, on flow patterns, temperature fields and the interface shape are illustrated through calculated results. Interface inversion from concave to convex, by modifying the ambient temperature profile, is also demonstrated through computer simulation. Particularly, through an inverse problem approach, a flat interface can be easily obtained for various operation conditions.

Recent developments in microwave GaAs technology are yielding devices with higher power capabilities and increased levels of integration. The mechanical and thermal properties of GaAs and other microwave materials play a key role in the design and assembly of microwave power circuits. Thermal management is a critical element of microwave power circuit design. Thermal properties of microwave materials are discussed and compared with standard microelectronic materials. Material selection criteria are described. Assembly and packaging techniques also affect the overall performance of the GaAs power circuit. The high operating frequencies of microwave circuits make ordinary circuit elements, such as wire bonds and printed conductors, reactive. In addition, electrical performance criteria, such as high current or low impedance, create unique assembly demands. The successful development of a GaAs‐based microwave product is dependent on careful attention to the material properties and precise assembly methods. Techniques of automated assembly and processing are discussed, with ah eye towards maintaining high quality and reliability.