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The definition of modeling languages is a key‐prerequisite for model‐driven engineering. In this respect, Domain‐Specific Modeling Languages (DSMLs) defined from scratch in terms of metamodels and the extension of Unified Modeling Language (UML) by profiles are the proposed options. For interoperability reasons, however, the need arises to bridge modeling languages originally defined as DSMLs to UML. Therefore, the paper aims to propose a semi‐automatic approach for bridging DSMLs and UML by employing model‐driven techniques.

The paper discusses problems of the ad hoc integration of DSMLs and UML and from this discussion a systematic and semi‐automatic integration approach consisting of two phases is derived. In the first phase, the correspondences between the modeling concepts of the DSML and UML are defined manually. In the second phase, these correspondences are used for automatically producing UML profiles to represent the domain‐specific modeling concepts in UML and model transformations for transforming DSML models to UML models and vice versa. The paper presents the ideas within a case study for bridging ComputerAssociate's DSML of the AllFusion Gen CASE tool with IBM's Rational Software Modeler for UML.

The ad hoc definition of UML profiles and model transformations for achieving interoperability is typically a tedious and error‐prone task. By employing a semi‐automatic approach one gains several advantages. First, the integrator only has to deal with the correspondences between the DSML and UML on a conceptual level. Second, all repetitive integration tasks are automated by using model transformations. Third, well‐defined guidelines support the systematic and comprehensible integration.

The paper focuses on the integrating direction DSMLs to UML, but not on how to derive a DSML defined in terms of a metamodel from a UML profile.

Although, DSMLs defined as metamodels and UML profiles are frequently applied in practice, only few attempts have been made to provide interoperability between these two worlds. The contribution of this paper is to integrate the so far competing worlds of DSMLs and UML by proposing a semi‐automatic approach, which allows exchanging models between these two worlds without loss of information.

This paper aims to propose a simulation-based performance evaluation model for the drone-based delivery of aid items to disaster-affected areas. The objective of the model is to perform analytical studies, evaluate the performance of drone delivery systems for humanitarian logistics and can support the decision-making on the operational design of the system – on where to locate drone take-off points and on assignment and scheduling of delivery tasks to drones.

This simulation model captures the dynamics and variabilities of the drone-based delivery system, including demand rates, location of demand points, time-dependent parameters and possible failures of drones’ operations. An optimization model integrated with the simulation system can update the optimality of drones’ schedules and delivery assignments.

An extensive set of experiments was performed to evaluate alternative strategies to demonstrate the effectiveness for the proposed optimization/simulation system. In the first set of experiments, the authors use the simulation-based evaluation tool for a case study for Central Florida. The goal of this set of experiments is to show how the proposed system can be used for decision-making and decision-support. The second set of experiments presents a series of numerical studies for a set of randomly generated instances.

The goal is to develop a simulation system that can allow one to evaluate performance of drone-based delivery systems, accounting for the uncertainties through simulations of real-life drone delivery flights. The proposed simulation model captures the variations in different system parameters, including interval of updating the system after receiving new information, demand parameters: the demand rate and their spatial distribution (i.e. their locations), service time parameters: travel times, setup and loading times, payload drop-off times and repair times and drone energy level: battery’s energy is impacted and requires battery change/recharging while flying.

EY's audit of German company Wirecard raises many questions about the quality of its audit. The scope and depth of the audit deficiencies have led some to call it: Germany's Enron. The authors review the facts of the case and raise broad-based questions that address EY's audit: what it did wrong, what other steps it might have taken to enhance the audit, and whether it can be characterized as a failed audit. The case provides learning objectives, implementation guidance, and answers to these questions. The authors believe that it can be used at both the undergraduate and graduate levels in courses dealing with accounting ethics, fraud in financial statements, and auditing.

The purpose of this paper is to explore the type of accounting scandals reported in Wikipedia which have occurred in different countries on different continents. It also explores the frequency and the dollar amount of the type of accounting scams that have been committed by the companies.

The paper analyses each company‘’s committed accounting scandal(s). It then classifies the companies on a country, type of scandal and industry basis. It further analyses the distribution of accounting scandals and explains the major ones in its category.

The paper concludes that within the confines of the information reported in Wikipedia, the majority of accounting scandals have occurred in USA both in number of scams and in USD amount. The most frequent type of accounting scam is overstatement of assets and understatement of liabilities including roundtrip sales. Another inference from the paper is that the accounting scams can occur anywhere at any amount. It is not a country-specific issue.

Auditors, accounting and auditing instructors and accountants talk about accounting scandals. Auditors, in particular, are required to issue audit reports that are free of material errors either deliberately or innocently made. This paper sheds light onto the issue, as it shows what major type of accounting scandals have been committed in the literature, as they had devastating repercussions on the shareholders.

Resources are scarce. Public’s savings must be sourced to the companies that produce the value added to the society. Misrepresentation of financial statements is an issue which distorts this relationship. The paper, by showing the type and amount of scandals, is opening up the issue to public that people be aware of what type of company they are investing in and what potential risks they are undertaking that may be leading them to be more selective in their investments.

The paper covers the original stories that have occurred throughout the world since 1970s. The names of the companies are original and the amounts of scams have either been collected as USD from the story itself or converted to USD at time of the event. All USD figures have then been restated to the 2011 year-end purchasing power. Thus, the cases are reflecting the approximate USD value as of 2011 year-end derived from its historical original value. The paper reshuffles the data in certain ways so that the reader will have a better view of the cases than that of presented in Wikipedia.

The purpose of this paper is to examine the predictability of the US‐based international mutual fund returns by investigating 2,479 daily observations for all categories of international equity, bond and hybrid mutual funds. Further, trading strategies are proposed and tested under different scenario including a proposed regulation by the Security and Exchange Commission (SEC).

The sample is split and the initial sub sample is used to investigate return patterns of international funds and to develop trading rules based on the predictable return patterns. Trading rules are then tested on the holdout sample.

Empirical results demonstrate statistically significant predictabilities. Various trading strategies show that the returns of both load and no‐load funds are economically significant beating a buy‐and‐hold strategy. Empirical findings are consistent across the fund categories irrespective of sizes and styles. The tested strategies are profitable even with various limits on frequency of trading, minimum holding periods and even under a recent SEC's proposed regulation. Further, possible contracting and regulatory changes are proposed to improve the efficiency in the mutual fund industry.

The results confirm previous findings of statistically and economically significant regularities from trading strategies that involve following the US markets. A test of SEC's proposed regulation documents that short‐term investors may benefit from active trading strategy even if the SEC's rule is implemented.

The purpose of this paper is to explore some commonly held beliefs about individuals investing in over-the-counter (OTC) stocks (those traded on Over-the-counter Bulletin Board (OTCBB) and Pink Sheets), a fairly pervasive activity. The authors frame the analysis within the context of direct gambling, aspirational preferences in behavioral portfolios, and private information.

Contrary to popular perceptions, the modeling of the deliberate act of buying OTC stocks at a discount brokerage house finds that unlike the typical lottery buyers/gamblers, OTC investors are older, wealthier, more experienced at investing, and display greater portfolio diversification than their non-OTC investing counterparts.

Behavioral portfolio investors (Shefrin and Statman, 2000) invest their money in layers, each of which corresponds to an aspiration or goal. Consistent with sensation seeking and aspirations in behavioral portfolios, OTC investors also display higher trading activity. Penny stocks seem to have different characteristics and trading behavior than other OTC stocks priced over one dollar. Irrespective of the price of OTC stocks, the authors find little evidence of information content in OTC trades.

The paper provides insight into individual investor decision making by empirically exploring the demographic and portfolio characteristics of individuals trading in OTC stocks.

Firms with linear pricing offer their customers the same price for each unit of a good or service. Anything else is nonlinear pricing. Nonlinear pricing in imperfect markets indicates a fundamental asymmetry in information between firms and consumers. Consumers are commonly expected to exhibit quality- or quantity-preference differences and have different reservation values for different product attributes. The firms, however, cannot observe consumers' preferences. When complete information regarding preferences is not observable, nonlinear pricing strategies with firms offering a menu or schedule of prices allow consumers to sort themselves according to their own preferences, resulting in market segmentation.

Supervisory control and data acquisition (SCADA) systems are widely used by utility companies during the production and distribution of oil, gas, chemicals, electric power, and water to control and monitor these operations. A cyber attack on a SCADA system cannot only result in a major financial disaster but also in devastating damage to public safety and health. The purpose of this paper is to survey the literature on the cyber security of SCADA systems and then suggest two categories of security solutions.

The paper proposes the use of secure socket layer/transport layer security (SSL/TLS) and IP security (IPsec) solutions, implemented on the test‐bed at the University of Louisville, as the optimal choices when considering the level of security a solution can provide and the difficulty of implementing such a security measure. The paper analyzes these two solution choices, discuss their advantages and disadvantages, and present details on efficient ways of implementing these solutions.

The SSL/TLS solution to the protocol security using public domain toolkits such as OpenSSL may provide a fast, effective, and economical solution. However, the SSL/TLS protocol and its implementation toolkits have their limitations so this approach may need another enhancement.

IPsec can be used to provide IP‐level security in addition to SSL/TLS.

The use of these enhanced security approaches in SCADA systems should effectively reduce the vulnerability of these critical systems to malicious cyber attacks, and thereby potentially avoiding the serious consequences of such attacks.

The purpose of this paper is to present a new outsourcing model for materials management related to the operating theatre of hospitals. Two distinguishing features characterize the model: the long-term collaborative network established among the supplying companies (the “Network factor”), and the implementation of the RFID technology along the supply chain (the “RFID factor”). The network factor allows sharing transportation costs, while the RFID factor allows implementing a continuous review policy, instead of the periodic review policy normally utilized in hospitals. In the paper the effect of these two factors on the minimization of total materials management costs is investigated.

An analytical model, validated through a simulation study, is proposed to calculate total management costs of materials, depending on the presence of the network and the RFID factors. Throughout the model it is possible to perform a scenario analysis and individuate the inventory management policy that allows minimizing total costs. The procedure has been applied to a real case study of a long-term collaborative network of supplying companies in the healthcare sector that operates in Central Italy.

The optimal inventory management policy strongly depends on the mutual distances of supplying companies and the hospital. Both of the two factors have an impact on the reduction of total annual costs. The analysis of the scenario shows that a positive interaction effect exists between the two factors, so that higher savings are obtained when both factors are present.

The outsourcing model presented in the paper is new, and the managerial insights that can be drawn from the application of the model to the healthcare sector can be extended to many other industries.

The capabilities of embedded devices such as smartphones are steadily increasing and provide the great flexibility of data access and collaboration while being mobile. From the distributed computing point of view, fundamental issues in mobile computing include heterogeneity in terms of varying device capabilities (i.e., operating systems and various hardware platforms), performance characteristics and real‐time behavior, and the ability to discover and interact with peers seamlessly. Web services are a family of XML based protocols to achieve interoperability among loosely coupled networked applications. We propose the use of Web services on embedded devices in order to solve interoperability issues in distributed mobile systems. We discuss various toolkits available for embedded devices and investigate performance characteristics of embedded Web services on smartphones. Our goal is to guide the design of Web services based applications on mobile devices, and provide estimates of performance that can be expected.