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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ejor.2006.05.031 Byline: Konstantinos G. Kouskouras (a), Andreas C. Georgiou (b) Keywords: Simulation; Discrete event simulation application; Software project management Abstract: The design and development of large-scale software projects is a complex endeavor, often facing problems like cost and schedule overruns as well as low quality. Over the last years the management of software development projects has been recognized as the cornerstone point of seeking improvement and solutions. Simulation modeling of the software project process is gaining interest among academics and practitioners, as a method to tackle the complex questions with which relevant enterprises are confronted. It offers support on several issues, such as defining software product development strategies, decision-making regarding process improvement and training, in a time span ranging from a short portion of the life cycle to long term product evolution, with organization-wide implications. The aim of this work is to implement a model simulating a core part of a software project process, enabling the estimation of several project development details such as delivery times and quality metrics. The purpose of the model is to assist project managers in control and monitoring, but also in identifying the best planning alternatives. The model scope covers a portion of the life cycle of an incremental software development venture. Author Affiliation: (a) INTRACOM TELECOM S.A., Thessaloniki Branch, 14th km Thessaloniki-Moudania, 57001 Thermi, Greece (b) University of Macedonia, Department of Business Administration, Business Excellence Laboratory, 156 Egnatia Street, 54006 Thessaloniki, Greece Article History: Received 29 June 2005; Accepted 24 May 2006

A goal programming model is presented to help in partner selection decisions in international joint ventures. The article discusses the researchers' quantitative model.

Abstract: A new model of nonisothermal adsorption is presented. The model is applicable to systems with nonlinear adsorption isotherm. Both intraparticle and film mass-transfer resistances are accounted in the model with the intraparticle mass-transfer rate being controlled by pore diffusion. An analytical solution of the model equations has been developed and a criterium for the existence of a maximum in the temperature uptake curves has been presented. A simple algorithm for the calculation of the maximum particle temperature has been illustrated. A detailed sensitivity analysis has shown the influence of various parameters on the temperature uptake curves. The model has been applied to the system water vapour–alumina and the predicted temperature uptake curves were compared with experimental results. [Copyright &y& Elsevier]

An asymptotically exact nonlinear driving force model of intra-particle mass-transfer rate for nonlinear isotherm systems with macropore diffusion control is presented. The obtained expression is compared with the solutions of the Fickian diffusion and adsorption model and excellent accuracy over the entire time (fractional uptake) domain is demonstrated. In the case of an irreversible isotherm the model reduces to the equations resulting from the shrinking core model a fact that guarantees its accuracy for highly nonlinear systems. The high accuracy of the model is further demonstrated by comparison with experimental data under various operational conditions. [Copyright &y& Elsevier]

We present a case of a 58 years old man with a large heterogeneous and well circumscribed soft tissue mass arising from the right pleural surface, found at a computer tomography of his chest. This mass after complete resection through a right lateral open thoracotomy, proved to be a Solitary Fibrous Tumor, previously known as ‘benign mesothelioma’. This tumor is usually discovered at routine chest X-rays since patients are either asymptomatic or report atypical symptoms. Only 10–20% of the published cases report a malignant solitary fibrous tumor, however, definite diagnosis can only be made after complete resection which is the proposed diagnostic algorithm for these cases. [ABSTRACT FROM AUTHOR]

• Risk criteria for urban flood risk assessment in value and spatial distribution. • Assessment of flood vulnerability and prioritization of mitigation projects. • Vulnerability as a multidimensional function under the sustainability pillars. • AHP coupled with a spatial database environment in GIS. • Vulnerability maps in to rank flood mitigation projects and spatial sensitivity analysis. Floods are among the most devastating consequences of global warming and can cause unprecedented disruptions in the operations of contemporary cities. Moreover, the sustainability of the limited water resources calls for a well-defined decision-making framework that facilitates the implementation of available measures. This study aims to establish a set of criteria for the comprehensive urban flood risk assessment and the creation of a prioritization map of flood mitigation projects. The proposed model is based on spatial data and expert opinions and is used for the flood vulnerability assessment and the project mitigation prioritization. The notion of vulnerability is decomposed on eighteen multidimensional factors which are also clustered under the so-called sustainability pillars; that is the environment, the society and the economy. In a second stage an Analytical Hierarchy Process (AHP) framework is coupled with a spatial database environment generated by a Geographic Information Systems (GIS) software and the outcome of the aforementioned process is included in a vulnerability map. The latter allows for the hierarchical grouping of the ranked future flood mitigation projects. Finally, spatial sensitivity analysis is conducted over the selected parameters and the effects on the resulting hierarchy are discussed. [ABSTRACT FROM AUTHOR]

Introduction: Several epidemiological studies have demonstrated that Obstructive Sleep Apnea (OSA) is a highly prevalent disorder in the general population and increases over time all over the world. The high prevalence is in part due to increasing rates of obesity. However, estimates of OSA prevalence in Southern Europe are generally lacking.Aim: The aim of our study was to predict the risk of OSA in the general population of Cyprus, the southeast part of Europe, by using a dedicated questionnaire like STOP-Bang.Subjects and Method: We screened 5736 sample housing units for eligible adults and a total population of 4118 eligible responders completed the STOP-Bang questionnaire. Participants were all adults, age 18 + residing in Cyprus. The sample was stratified according to the last demographic report (2016) by district, rural or urban area, gender and age and the estimated sample size needed was 2000. Our survey was conducted by Computer Aided Telephone Interviewing (CATI) method. The question about Neck Circumference was removed from the final evaluation due to the uncertainty of most of the participants and the risk of bias.Results: From a total of 4118 participants (2252 males - 54.7%, 1862 females - 45.3%), with 46.6% over 50 years old, 2641 (64.1%) were at low risk for OSA (0-2 positive answers), 1200 (29.1%) at intermediate risk (3-4 positive answers) and 277 (6.7%) at high risk (≥5 positive answers). In sum, 29.9% responded positively for snoring, 39.3% for feeling tired or sleepy during the day, 12.3% for observed apnea during sleep, and 24.6% for having or being treated for hypertension. Class II and III obesity with Body Mass Index (BMI) > 35 kgr/m2 was observed in 192 subjects (4.7%). In the subpopulation of obese participants (BMI>30 kg/m2), intermediate to high risk of OSA was present in 45%, whereas in obesity class II and III the percentage reached almost 90%.Conclusions: Our survey yielded that the prevalence of intermediate to high risk for OSA was 50% in males and 18% in females, in the general population of Cyprus. These findings were similar to previously reported high OSA prevalence worldwide, considering the fact that a single questionnaire is only a screening tool and cannot alone diagnose sleep apnea. [ABSTRACT FROM AUTHOR]