University of Piraeus

About: University of Piraeus is a education organization based out in Piraeus, Attiki, Greece. It is known for research contribution in the topics: Context (language use) & Computer science. The organization has 1731 authors who have published 6209 publications receiving 106699 citations.

ISO 9001 overall performance dimensions: an exploratory study

Abstract: Purpose – The purpose of this paper is to validate and assess the performance dimensions reflecting ISO 9001 benefits in service companies and to determine their relationships. Design/methodology/approach – A research study was carried out in 198 ISO 9001:2008 certified Greek service companies. Data were obtained through a structured questionnaire and have been analyzed with exploratory and confirmatory factor analyses. Findings – Four performance dimensions reflecting ISO 9001 benefits are extracted and validated, namely, product/service quality, operational, market and financial performance. Research limitations/implications – The research sample is limited to small and medium-sized enterprises operating in a specific European country. Further research may confirm the findings of this study to other countries as well. Practical implications – By determining and evaluating the performance dimensions and their inter-relationships, the ISO 9001 certified service companies are assisted to select an appropri...

LIDF: Layered intrusion detection framework for ad-hoc networks

Abstract: As ad-hoc networks have different characteristics from a wired network, the intrusion detection techniques used for wired networks are no longer sufficient and effective when adapted directly to a wireless ad-hoc network. In this article, first the security challenges in intrusion detection for ad-hoc networks are identified and the related work for anomaly detection is discussed. We then propose a layered intrusion detection framework, which consists of collection, detection and alert modules that are handled by local agents. The collection, detection and alert modules are uniquely enabled with the main operations of ad-hoc networking, which are found at the OSI link and network layers. The proposed modules are based on interpolating polynomials and linear threshold schemes. An experimental evaluation of these modules shows their efficiency for several attack scenarios, such as route logic compromise, traffic patterns distortion and denial of service attacks.

Incentives and Female Entrepreneurial Activity: Evidence from Panel Firm Level Data

Abstract: The goal of this paper is to investigate entrepreneurial activity and to analyze the incentives of female participation in the labor market. Female entrepreneurial activity is closely related to social and economic issues. They represent a driving force, active and effective members of economic, political, professional and managerial societies. On the other hand, they have families with serious maternal responsibilities and inelastic household obligations, roles which they are trying to balance effectively. To that reason, specific actions and carefully designed measures are essential in encouraging and promoting them to engage into entrepreneurial activity. To investigate the issue of entrepreneurial activity, personal characteristics and various motivation incentives are examined in order to determine the major factors that may influence female entrepreneurial spirit in Greece. Obtaining data from 1600 industrial firms located in the prefecture of Piraeus over the period 1999–2009, this study makes use of the panel methodology approach to provide evidence about the main determinants of female entrepreneurship. What is found is that a combination of pull and push motives and effective mentoring framework, in addition to a set of personal characteristics such as risk of failure, educational level, creativity, innovativeness, ambitiousness and marital status, seem important for the encouragement of women entrepreneurship in Greece to start up a new business. The implications seem very substantial for the formulation and implementation of effective support policies and measures for female entrepreneurs’ vital start up and early stage period.

Distributions of numbers of success runs of fixed length in Markov dependent trials

Abstract: Let {Zn, n ≥ 1} be a time-homogeneous {0, 1}-valued Markov chain, and let Nn be a random variable denoting the number of runs of "1" of length k in the first n trials. In this article we conduct a systematic study of Nn by establishing formulae for the evaluation of its probability generating function, probability mass function and moments. This is done in three different enumeration schemes for counting runs of length k, the "non-overlapping", the "overlapping" and the "at least" scheme. In the special case of i.i.d. trials several new results are established.