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We discuss the device applications of a new impact ionization model. This model is based on a new formulation of the impact ionization rate for bulk semiconductors, derived from solvable high‐field Boltzmann transport equations. The model inputs are relaxation times which simulate the dominant electron‐phonon scatterings and are calibrated by realistic Monte Carlo simulations. Our impact ionization model is shown to be physically motivated and is easily implemented in the standard hydrodynamic device simulators HFIELDS and FIELDAY. An efficient numerical scheme is used to simulate three thin‐base silicon bipolar transistors. Results based on this impact ionization model are found to agree well with the experimental multiplication factors over a large range of applied voltages. These results are contrasted with the more phenomenological treatment of Scholl and Quade which is shown to be a low‐field limit of our model.

A 2D numerical simulation using a finite element technique is presented for computing spreading resistance of a semiconductor buried ridge stripe laser. The simplified physical model is analyzed from the functional analysis point of view and a proof of existence and uniqueness of the nonlinear partial differential equations obtained from this simplified model is given. The discrete associated nonlinear problem is solved on triangular finite elements using conjugate gradient algorithms. Some results are presented for a specific semiconductor laser

An energy transport model has been numerically implemented in the device simulator HFIELDS. The transport parameters for the standard hydrodynamic model and the energy transport model are calibrated by means of DAMOCLES, a two‐dimensional Monte Carlo Boltzmann equation solver. We analyse the relative merits of these two models by comparing their predictions of the energy and velocity distributions for a bipolar transistor and a ballistic diode. In the cases presented, the hydrodynamic model is found to agree with the Monte Carlo results more closely than the energy transport model.

In 2001, the US moved to regulate internal control reporting by management and auditors. While some jurisdictions have followed the lead of the US, many others have not. An important question, therefore, is the relevance of internal control to stakeholders. The more specific issue of the benefits of US-style regulation of internal control reporting is also topical. We review studies on the determinants of internal control quality and its economic consequences for stakeholders including investors, creditors, managers, auditors and financial analysts. We extend previous reviews by focusing on US studies published since 2013 as well as all non-US studies investigating IC quality including countries regulating IC disclosure as well as unregulated settings and both developed and developing economies. In doing so, we identify research questions where evidence remains mixed and new directions in which there are research opportunities.

Three main insights arise from our analysis. First, evidence on the economic consequences of internal control quality suggests that the quality of internal control can have a significant effect on decision making by users of financial information. Second, the results of research on the empirical association between ownership structure, certain board characteristics and internal control quality is generally mixed. Empirical evidence concerning the association between audit committee characteristics and internal control quality generally supports a positive and significant association. Finally, while studies in non-US jurisdictions are increasing, opportunities remain to explore the determinants and consequences of internal control in other jurisdictions. Our review provides evidence for policy makers of whether there are benefits from requiring management and auditors to report on internal control over financial reporting.

This paper presents a new discretization technique of the hydrodynamic energy balance model based on a finite‐element formulation. The concept of heat source lumping is introduced, and the thermal conductivity model includes the effect of varying both carrier concentrations and temperatures. The energy balance equation is formulated to account for kinetic energy as a convective flow. The new discretization method has the advantage that it allows for assembling the functions out of elementary variables available over elements instead of along element links. Therefore, theoretically, calculation of the Jacobian should be three times faster than by the classic method. Results are given for three examples. The method suffers from mathematical instabilities, but provides a good basis for future work to solve these problems.

Ramadan intermittent fasting (RIF) has produced heterogeneous and domain-specific effects on cognitive function. This study aims to investigate the effect of RIF on verticality perception or estimation of subjective visual vertical (SVV) in young adults. The significance of SVV is that it is essential for spatial orientation, upon which many daily activities depend.

Verticality perception was assessed with a computerized rod and frame test (CRFT) in two visual conditions: without a surrounding frame and with a distracting tilted frame. The tilted frame condition measures level of visual dependence or reliance of visual cues for posture and orientation. In total, 39 young adult men were recruited at different stages of Ramadan fasting: 21 were tested at the end of the first week (Week 1) and 18 others at the end of the third week (Week 3) of Ramadan. Also, 39 participants were recruited to serve as a non-fasting control group. Factorial ANOVA analyses were conducted to identify the main effects of fasting status, time-of-day and the interaction between them on blood glucose levels, nocturnal sleep duration and vertical alignment errors.

The main effect of fasting status on glucose level was significant (p = 0.03). There was a significant time-of-day main effect on glucose levels (p = 0.007) and sleep duration (p = 0.004) only in fasting participants. Neither the main effects of fasting status nor time-of-day were significant for rod alignment errors in both visual conditions. The interaction of fasting status and time-of-day was not significant either. This may indicate that any negative effect of Ramadan fasting on activities that are critically dependent on verticality perception and spatial orientation, such as sports and driving, may not be due to verticality misperception.

The present study was the first to investigate the effect of Ramadan fasting on spatial orientation. It demonstrated robustness of verticality perception to fasting status and the point of fasting during Ramadan. Verticality perception was also unaffected by time-of-day effects in non-fasting and fasting groups at two different points of Ramadan. This study corroborates others reporting heterogeneous effects of Ramadan fasting on cognitive function.

The effects of integrated reporting quality (IRQ) have been debated in increasing empirical studies. Several IRQ measures, different theoretical approaches and multiple contexts have been adopted and investigated, leading to mixed results. By using the meta-analytic technique, this study aims to contribute to the accounting literature, reconciling the conflicting results on the effects of IRQ and providing objective conclusions to complement narrative literature reviews.

A sample of 45 empirical papers from 2013 to 2022, with 653 effect sizes, was used to assess the effects associated with IRQ. The papers were clustered into five groups (market reaction, financial performance, cost of capital, financial analysts’ properties and managerial decisions) based on the different consequences of IRQ investigated in the primary studies. A random-effects meta-regression model was used to explore all sources of heterogeneity together.

The meta-regression results confirm that IRQ positively influences firms’ market valuation and financial performance and hampers opportunistic managerial behaviour by improving corporate transparency, mitigating information asymmetry and encouraging accountability. Moreover, differences in the study characteristics affect the strength of the relationship object of interest.

Through meta-analysis, this study provides a broader overview of the effects of IRQ by enhancing the generalisability of the findings. The results also pave the way for additional evidence on the outcome variables affected by the quality of integrated disclosure.

The paper examines ways that Knowledge Management (KM) can demonstrate practical value for organizations. It begins by reviewing the claims made about KM, i.e. the benefits KM can provide to organizations. These claims are compared with traditional firm performance metrics to derive a criterion to measure the value of KM. Seven practical outcomes of KM are then presented as methods to persuade managers to invest in KM. These practical outcomes are then evaluated against the value criterion. The paper is based on empirical evidence from a five year longitudinal study.

This paper is based on a longitudinal change project for a large Australian Research Council (ARC) Linkage Project grant in the period 2008-2013. The Project was a transformational change program which aimed to help make the partner organisation a learning organisation. The partner organisation was a large Australian Government Department, which faced the threat of knowledge loss caused by its ageing workforce. The sample was 118 respondents, mainly engineering and technical workers. A total of 150 respondents were invited to participate in the study which involved an annual survey and attendance at regular training workshops and related activities, with a participation rate of 79 per cent.

This paper provides a checklist from which to evaluate KM in terms of financial and non-financial measures and seven practical outcomes from which to identify the organisational problem which may be addressed by KM. Lead and lag indicators – what needs to be done and what will result – are also provided. Managers may use this framework to identify the value proposition in any KM investment.

The research is based on a single case study in a public sector organization. While the longitudinal nature of the study and the rich data collected offsets this issue, it also presents good opportunities for researchers and practitioners to test the ideas presented in this paper in other industry contexts. The seven practical outcomes also vary in the maturity of the empirical evidence supporting KM ' s impact. Strategic alignment, value management, and psychological contract, in particular, are still under-developed and could be areas for specific further research testing the ideas presented here.

This paper argues that investment decisions regarding KM may benefit from focusing on significant and on-going organisational problems, which will connect KM with firm performance and demonstrate financial and non-financial impact. The seven practical outcomes were evaluated against measurement criteria and against KM ' s claims. Overall, common themes were time and cost, as well as capability growth and performance improvements. Financial impact was mainly found in cost savings. Non-financial impact was found across the seven practical outcomes. It provides management with a checklist to make investment decisions regarding KM.

The decision whether to invest in KM begins with methods used to evaluate any organisational project. Managers must determine first whether necessary funds are available; and then whether the project is worthwhile. The standard method for evaluating a project ' s worth is return on investment (ROI). However, calculating ROI for KM investment is problematic. Unless KM can be proven to directly improve performance in financial terms, managers may struggle to see its ROI. The paper begins by reviewing the claims made about KM, i.e. the benefits KM can provide to organizations. These claims are compared with traditional firm performance metrics to derive a criterion to measure the value of KM.

We present a semi‐quantum model including tunneling effects across an abrupt heterojunction. The discontinuity of the effective masses and the energy bands are considered. The quantum transmission conditions for the quasi‐Fermi levels are obtained using WKB approximation. We use mixed finite element approach and a two dimensional mesh which is double‐valued for quasi‐Fermi levels at a heterojunction. A GaAs/GaAIAs heterojunction diode is then simulated using both drift‐diffusion and semi‐quantum model by varying doping density at low temperature.

The purpose of this paper is to examine the relationship between human capital (HC) and value creation and employee reward. HC is an important component of intellectual capital (IC). There is growing interest in how IC can be used to create organizational value. This paper addresses the need for critical analysis of IC practices in action. Based on data gathered from three annual surveys at Australia’s second largest public sector organization, the paper introduces psychological contract (PC) as new HC factors, and develops a method to measure HC in terms of value creation (work activity) and employee reward (pay). The findings have practical implications for managers in using the paper’s HC measurement to achieve strategic alignment (SA) of the workforce.

The research was based on data gathered from three annual surveys (2009-2011) of staff at Australia’s second largest public sector organization. A total of 248 questionnaires were completed. Three independent variables conceptualized HC: first, employee capability (HC1); second, employee satisfaction (HC2); and third, employee commitment (HC3). Two dependent variables were tested: work activity and pay. The data collected in this study was analyzed through the use of bivariate correlation and linear regression using SPSS software.

The paper’s major finding is that HC1 (employee capability) and HC2 (employee satisfaction), had a direct positive relationship with the importance of work activity. The paper’s second finding was that only HC1 has a direct positive relationship with the pay. However, HC3 (employee commitment) had a direct negative relationship with the importance of work activity. Further, HC2 and HC3 had no relationship with pay. The research project organization (RPO) achieved SA with employees’ capability and motivation; as well as employee capability and pay. However, inequities emerge in terms of employee commitment and value creation (work activity) and in the PC factors and pay.

While the research findings are limited by them being based on a single RPO, this is offset to some degree by the longitudinal nature of the study and the size of the RPO. It also presents opportunities for further research, particularly in terms of further testing of the new conceptualization of HC in other organizations and industry settings, and investigation of the failed hypotheses: PC and pay; and employee commitment and work activity.

While strong PC employees are being asked to do important work, they are not always being paid at the rate of colleagues doing similar work. This will create perceptions of distributive justice, which will make those with strong PC unhappy, thereby decreasing their PC, disrupting the SA of the value creation, and lead to employee turnover. Managers can address this problem by using the HC method outlined in this paper to introduce methods such as merit increases and variable pay. While this is problematic for public sector organizations often constrained by having to fit salary awards, innovative organizations are increasingly considering more flexible pay systems.

The paper introduces a new conceptualization of HC, and two proxies for organizational performance: pay and work activity. The paper addresses calls for IC in practice research to make the field more relevant for practitioners. The HC model introduced will allow managers to act on IC measurement by linking HC value with adequate pay, increasing motivation, commitment, and productivity, leading to increased innovation and reduced employee turnover.