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.

Do Tourism Providers Know their Visitors? An Investigation of Tourism Experience at a Destination:

Abstract: Even dominant positivist researchers recognise the insufficiencies of traditional services research methodology and claim that the dominant models of service quality's measurement have failed to re...

The Role of the Rating Companies in the Recent Financial Crisis in the Balkan and Black Sea Area

Abstract: The main aim of this article is to demonstrate a holistic framework for measuring a bank’s financial health by classifying its main responsibilities between conformance and performance. Responsibilities are classified into five categories as follows: First, Corporate Financial Reporting (CFR) that integrates General Accepted Accounting Principles (GAAP), Generally Accepted Auditing Standards (GAAS), Securities Exchange Commission (SEC), Financial Services Authority (FSA), and International Accounting Standards (IAS). Second, Risk Management Procedures (RMP), that incorporates methods and directives which arise from Basel I, Basel II, Capital Adequacy frameworks or solvency ratio benchmarks. Third, Corporate Governance (CG), that integrates Sarbanes – Oxley Act, Audit Committees, and Internal Audit Mechanisms. Fourth, Corporate Social Responsibility (CSR), that consists of instructions and standards such as Global Reporting Initiative (GRI) – social and environmental, Social accountability (SA 8000) – working conditions, International Organization for Standardization (ISO 9000). Fifth, Stockholders Value Creation (SVC), that is a set of methodologies and ratios used in order to measure value creation for shareholders such as Strategic and Balanced scorecard, Economic Value Added EVA®, and other business performance management tools. On the other, the Rating Agencies (RA) applies various rating systems in different fields.

Improving LoRa Network Capacity Using Multiple Spreading Factor Configurations

Abstract: LoRa networks enable long range communications for Internet of Things (IoT) applications The current LoRa technology provides a wide range of communication settings whereas many combination settings are orthogonal and, thus, they can be successfully decoded at the gateway when the signals are transmitted simultaneously Previous simulation results showed that the LoRa network capacity can be improved when multiple communication parameters are applied In this paper, we model a LoRa network consisting of nodes with different communication settings in terms of bandwidth and spreading factor We compute the average success probability per configuration as a function of density taking into account both intra and inter-spreading factor collisions We, also, formulate and solve an optimization problem to maximize the node capacity for a given deployment area and frequency by optimizing the number of nodes having different spreading factor configurations We present numerical results and we show that solutions close to the optimal can increase the maximum number of nodes by more than 700% compared to case where equal number of users per spreading factor are considered

Development of an Electrochemical Biosensor for the Rapid Detection of Saxitoxin Based on Air Stable Lipid Films with Incorporated Anti-STX Using Graphene Electrodes

Abstract: A miniaturized potentiometric saxitoxin sensor on graphene nanosheets with incorporated lipid films and Anti-STX, the natural saxitoxin receptor, immobilized on the stabilized lipid films is described in the present paper. An adequate selectivity for detection over a wide range of toxin concentrations, fast response time of ca. 5–20 min, and detection limit of 1 nM have been achieved. The proposed sensor is easy to construct and exhibits good reproducibility, reusability, selectivity, long shelf life and high sensitivity of ca. 60 mV/decade of toxin concentration. The method was implemented and evaluated in lake water and shellfish samples. This novel ultrathin film technology is currently adapted to the rapid detection of other toxins that could be used in bioterrorism.