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Standard treatments of the field emission problem typically rely on approximations to the evaluation of the Transmission Coefficient (TC). Recently, the Wigner Distribution Function (WDF) has been applied to this problem. In this paper, fast, accurate, and efficient numerical algorithms for each are presented and compared to each other and to traditional WKB and Fowler Nordheim approaches for silicon field emission. As each approach admits a trajectory interpretation, the methods for incorporating each into a larger Ensemble Particle Monte Carlo (EPMC) simulation of quantum transport are briefly discussed.

In this work we outline the methodology by which the Wigner Distribution Function (WDF) may be applied to the simulation of field emission from silicon into the vacuum so that the effects of self‐consistently calculated band bending and scattering on the current‐field characteristics may be assessed. For the first time, current saturation‐like effects are simulated. We analyze this in light of the behavior of the self‐consistent potential and density profiles at high applied fields.

A novel approach to many‐body quantum transport theory which emphasize the role of localized orbitals, and their lattice Fourier transforms, as dynamical basis states is given. The formalism allows for the calculations of particle quantum trajectories, describing individual elementary space and time‐dependent events in quantum processes. It is demonstrated that the particle quantum trajectories exhibit behavior quite identical to that of classical particles acted upon by a new “effective quantum force”. The present technique for calculating the quantum force can be applied to a procedure for incorporating space and time‐dependent quantum tunneling in Selfconsistent Ensembe Particle Monte Carlo (SEPMC) technique for multidimensional device analysis.

Intrinsic high‐frequency oscillations (≈2.5 THz) in current and corresponding quantum well density, which have been simulated for a fixed bias voltage in the Negative Differential Resistance (NDR) region of the Current‐Voltage (I‐V) characteristics of a Resonant Tunneling Diode (RTD), suggest an equivalent nonlinear autonomous circuit model. The intrinsic circuit parameters are calculated directly from the results of the quantum transport numerical simulations. These consist of a resistor in series with a two‐branch parallel circuit, one branch consists of a capacitor and the other branch consists of an inductor in series with a nonlinear resistor. It is however suggested that much more complex external circuit‐induced behavior can occur in real RTD experiments.

This paper explores the value of financial statement auditing in the public sector. The study applies theory about auditing from the private sector as well as the public sector to explore ways in which public sector auditing can be expected to be valuable. It shows that there are a number of complementary explanations that can be applied to examine the value of public audit, including agency, signaling, insurance, management control, governance and confirmation explanations. The evidence from research and history is generally consistent with the agency and management control explanations. There is some support for the signaling and insurance explanations, while research evidence suggests that governance has differing impact in the public sector compared to the private. The confirmation hypothesis is also potentially relevant. Reviewing the history of the development of public sector auditing functions shows that at least some developments were consistent with explanations such as agency theory and management control. Auditing in the public sector is an area where more research is valuable. The paper concludes with a discussion of issues for further investigation.

Information distortion results in demand variance amplification in upstream supply chain members, known as the bullwhip effect, and inventory inaccuracy in the inventory records. As inventory inaccuracy contributes to the bullwhip effect, the purpose of this paper is to investigate the impact of inventory inaccuracy on the bullwhip effect in radio-frequency identification (RFID)-enabled supply chains and, in this context, to evaluate supply chain performance because of the RFID technology.

A simulation modeling method based on hierarchical timed colored petri nets is presented to model inventory management in multi-stage serial supply chains subject to inventory inaccuracy for various traditional and information sharing configurations in the presence and absence of RFID. Validation of the method is done by comparing results obtained for the bullwhip effect with published literature results.

The bullwhip effect is increased in RFID-enabled multi-stage serial supply chains subject to inventory inaccuracy. The information sharing supply chain is more sensitive to the impact of inventory inaccuracy.

Information sharing involves collaboration in market demand and inventory inaccuracy, whereas RFID is implemented by all echelons. To obtain the full benefits of RFID adoption and collaboration, different collaboration strategies should be investigated.

Colored petri nets simulation modeling of the inventory management process is a novel approach to study supply chain dynamics. In the context of inventory errors, information on RFID impact on the dynamic behavior of multi-stage serial supply chains is provided.

This study reviews the existing literature on the U.S. peer review system and the Public Company Accounting Oversight Board (PCAOB) inspection system to assess our knowledge of audit regulation. The traditional self-regulatory system of the accounting profession came to an end, in 2002, when the PCAOB was established to oversee the audit firms of publicly traded companies. This paper contributes to the controversial debate about self-regulation versus independent regulation by analyzing, categorizing, and comparing the research findings on the peer review system and the PCAOB system along three dimensions: the validity of peer reviews and PCAOB inspections, the recognition of reviews and inspections by decision-makers (e.g., investors, bankers, committees), and the effect of reviews and inspections on audit quality. Synthesizing the research on the regulatory regimes suggests that the notion of external quality control, both through peer reviews and government inspections, is positively linked with an improvement of audit quality. At the same time, the analysis indicates that external users do not seem to recognise peer review and PCAOB reports as very useful instruments for decision-making, which is in line with an identified rather skeptical perception of the audit profession on reviews and inspections. Overall, this study reveals that although the academic literature on peer review and PCAOB inspection is extensive it has not produced definitive conclusions concerning various aspects of audit regulation. This paper shows how this blurred picture is due to conflicting research findings, the dominance of the quantitative research paradigm, and unchallenged assumptions within the literature, and concludes by proposing research opportunities for the future.

We investigate the effect of the PCAOB’s Part II report on annually inspected firms’ audit fees and audit quality. The PCAOB replaced the peer review auditor program with an independent inspection of audit firms. Upon completion of each inspection, the PCAOB issued inspection reports that include a public portion (Part I) of identified audit deficiencies, and (in most cases) a nonpublic portion (Part II) of identified quality control weaknesses. The Part II report is only made public when the PCAOB deems that remediation was insuffcient after at least 12 months have passed. Starting around the time of the 2007 Deloitte censure (Boone et al., 2015), the PCAOB shifted from a soft synergistic approach to an antagonistic approach, such that Part II reports were imminent, despite delays that ultimately led to their release one to four years later than expected. Our study spans the period from 2007 to 2015, and examines the effect on audit fees and audit quality at the earliest date that the Part II report could have been released – 12 months after the Part I report was issued. We find that following the 12 month period, that annually inspected audit firms eventually lost reputation by lower audit fees, while they concurrently made remedial efforts to increase the quality of their client’s financial reporting quality (abnormal accruals magnitude and restatements). However, three years after the Part II report was actually released, audit fees increased.

Mashups have been studied extensively in the literature; nevertheless, the large body of work in this area focuses on service/data level integration and leaves UI level integration, hence UI mashups, almost unexplored. The latter generates digital environments in which participating sources exist as individual entities; member applications and data sources share the same graphical space particularly in the form of widgets. However, the true integration can only be realized through enabling widgets to be responsive to the events happening in each other. The authors call such an integration “widget orchestration” and the resulting application “mashup by orchestration”. This article aims to explore and address challenges regarding the realization of widget‐based UI mashups and UI level integration, prominently in terms of widget orchestration, and to assess their suitability for building web‐based personal environments.

The authors provide a holistic view on mashups and a theoretical grounding for widget‐based personal environments. The authors identify the following challenges: widget interoperability, end‐user data mobility as a basis for manual widget orchestration, user behavior mining – for extracting behavioral patterns – as a basis for automated widget orchestration, and infrastructure. The authors introduce functional widget interfaces for application interoperability, exploit semantic web technologies for data interoperability, and realize end‐user data mobility on top of this interoperability framework. The authors employ semantically enhanced workflow/process mining techniques, along with Petri nets as a formal ground, for user behavior mining. The authors outline a reference platform and architecture that is compliant with the authors' strategies, and extend W3C widget specification respectively – prominently with a communication channel – to foster standardization. The authors evaluate their solution approaches regarding interoperability and infrastructure through a qualitative comparison with respect to existing literature, and provide a computational evaluation of the behavior mining approach. The authors realize a prototype for a widget‐based personal learning environment for foreign language learning to demonstrate the feasibility of their solution strategies. The prototype is also used as a basis for the end‐user assessment of widget‐based personal environments and widget orchestration.

The evaluation results suggest that the interoperability framework, platform, and architecture have certain advantages over existing approaches, and the proposed behavior mining techniques are adequate for the extraction of behavioral patterns. User assessments show that widget‐based UI mashups with orchestration (i.e. mashups by orchestration) are promising for the creation of personal environments as well as for an enhanced user experience.

This article provides an extensive exploration of mashups by orchestration and their role in the creation of personal environments. Key challenges are described, along with novel solution strategies to meet them.

Corporates have recently invested in company-owned makerspaces with the goal to skim the potential of makerspaces as innovation driver. The purpose of this paper is to introduce the first framework describing elements and the innovation-related impact on users of corporate makerspaces (CMSs).

The CMS framework is based on a critical review of 116 scientific articles on makerspaces and the embedding of the review findings into the corporate context.

A prototyping infrastructure, a community infrastructure and facilitators are proposed to be key elements of CMSs. Further, CMSs are suggested to have an impact on ideation, concept iteration during the innovation process and collaboration of its users.

The framework on CMSs is based on a critical review of makerspace literature and not on empirical research data.

This paper sheds light on key elements and the expected innovation-related impact of a CMS on the users and thus contains useful information for corporate innovation management on how to plan, build and implement a CMS.

To the best of the authors’ knowledge, this paper is the first review of makerspace literature with focus on their elements and innovation-related impact. Additionally, the review provides the first academic definition of the growing phenomenon of CMSs and describes elements and the innovation-related impact of CMSs on its users in companies, which paves the way for further research on CMSs.