Time filter

Source Type

Chania, Greece

The Technical University of Crete is a state university under the supervision of the Greek Ministry of Education and was founded in 1977 in Chania, Crete. The first students were admitted in 1984. The campus is located on a panoramic site in the peninsula of Maelehas and covers an area of 750 acres , 7 km Northeast of Chania. Library, cafeterias, and students' dormitories are located on campus.The Technical University of Crete ranks highly among the best Greek universities in terms of research productivity, research funding, scientific publications and citation per faculty member. In addition the departments of the Technical University of Crete are highly competitive. The students enter the University after scoring high scores in the National Examinations organized annually for this purpose by the Greek Government.The purpose of the institution is to conduct research, to provide under-graduate and graduate educational programs in modern engineering fields as well as to develop links with the Greek industry. With a total of 210 research and development programs and a budget approaching the amount of 19,000,000 Euro, the Technical University of Crete is among the top in Greece in Performing research. In addition, the Technical University of Crete is among the first and top Greek institution with the highest rate of research publications per faculty member. One of its scope is to strengthen even more the basic science offered in the department curricula and to attract the best researchers.The Technical University of Crete is an Institution, which gives emphasis on both teaching and research. The 57 laboratories are very well equipped with high technology infrastructure and well skilled personnel. Concerning the faculty members, most of them had already an international career, before coming to TUC. Wikipedia.

Nitrous oxide (N2O) is the largest stratospheric-ozone-depleting substance, being concomitantly the third most potent greenhouse gas. The direct catalytic decomposition of N2O (deN2O process) is one of the most promising remediation technologies for N2O emissions abatement. Although noble metals (NMs)-based catalysts demonstrate satisfactory deN2O performance, their high cost and sensitivity to various effluent stream components (e.g., water vapor, oxygen) limit their widespread industrial applications. Hence, the development of NMs-free catalysts of low cost and satisfactory deN2O performance is of paramount importance. This survey appraises the recent advances, which have been reported since 2000, on N2O decomposition over non-noble-metal oxidic catalysts. Initially, a brief overview of N2O sources, environmental consequences, and remediation technologies is provided. The literature related to the deN2O process over NMs-free metal oxides (MOs) is categorized and critically discussed, as follows: (i) bare oxides, (ii) hexaaluminates, (iii) hydrotalcites, (iv) spinels, (v) perovskites, and (iv) mixed metal oxides not belonging in the above categories. This review covers several aspects with respect to the reaction mechanisms, the structure-activity correlations, the role of various inhibitors (e.g., O2, NO, H2O) as well as the strategies followed to adjust the local surface structure of MOs. Fundamental insights toward fine-tuning of surface chemistry of MOs by means of advanced preparation routes and/or electronic promotion are also provided, paving the way for real-life energy and environmental applications, beyond the deN2O process. © 2015 American Chemical Society. Source

Koutsakis P.,Technical University of Crete
IEEE Transactions on Vehicular Technology

The worldwide popularity of wireless local area networks (WLANs) calls for efficient solutions in scheduling multimedia (voice, data, and video) traffic transmissions. Enhanced distributed channel access (EDCA), which is the contention-based channel access function of IEEE 802.11e, is unable to guarantee priority access to higher priority traffic in the presence of significant traffic loads from low-priority users. In this paper, we propose the use of a token- and self-policing-based scheduling scheme, which not only addresses this problem but also prevents bursty video nodes from overusing the medium and tackles the problem of idle time due to large transmission opportunities (TXOPs). © 2011 IEEE. Source

Particle Swarm Optimization (PSO) is a highly efficient evolutionary optimization algorithm. In this paper a multiobjective optimization algorithm based on PSO applied to the optimal design of photovoltaic grid-connected systems (PVGCSs) is presented. The proposed methodology intends to suggest the optimal number of system devices and the optimal PV module installation details, such that the economic and environmental benefits achieved during the system's operational lifetime period are both maximized. The objective function describing the economic benefit of the proposed optimization process is the lifetime system's total net profit which is calculated according to the method of the Net Present Value (NPV). The second objective function, which corresponds to the environmental benefit, equals to the pollutant gas emissions avoided due to the use of the PVGCS. The optimization's decision variables are the optimal number of the PV modules, the PV modules optimal tilt angle, the optimal placement of the PV modules within the available installation area and the optimal distribution of the PV modules among the DC/AC converters. © 2010 Elsevier Ltd. Source

Santamouris M.,National and Kapodistrian University of Athens | Kolokotsa D.,Technical University of Crete
Energy and Buildings

Passive cooling in the built environment is now reaching is phase of maturity. Passive cooling is achieved by the use of techniques for solar and heat control, heat amortization and heat dissipation. Modulation of heat gain deals with the thermal storage capacity of the building structure, while heat dissipation techniques deal with the potential for disposal of excess heat of the building to an environmental sink of lower temperature, like the ground, water, and ambient air or sky. The aim of the present paper is to underline and review the recent state of the art technologies for passive cooling dissipation techniques in the built environment and their contribution in the improvement of the indoor environmental quality as well as in the reduction of cooling needs. The paper starts with a short introduction in passive cooling and continues with the analysis of advanced heat dissipation techniques such as ground cooling, evaporative cooling, and night ventilation in the built environment. The various technologies are compared versus their contribution to energy efficiency and users' comfort. Future trends and prospects are discussed. © 2012 Elsevier B.V. Source

Vamvuka D.,Technical University of Crete
International Journal of Energy Research

As the global demand for energy rapidly increases and fossil fuels will be soon exhausted, bio-energy has become one of the key options for shorter and medium term substitution for fossil fuels and the mitigation of greenhouse gas emissions. Biomass currently supplies 14% of the world's energy needs. Biomass pyrolysis has a long history and substantial future potential-driven by increased interest in renewable energy. This article presents the state-of-the-art of biomass pyrolysis systems, which have been-or are expected to be-commercialized. Performance levels, technological status, market penetration of new technologies and the costs of modern forms of biomass energy are discussed. Advanced methods have been developed in the last two decades for the direct thermal conversion of biomass to liquid fuels, charcoals and various chemicals in higher yields than those obtained by traditional pyrolysis processes. The most important reactor configurations are fluidized beds, rotating cones, vacuum and ablative pyrolysis reactors. Fluidized beds and rotating cones are easier for scaling and possibly more cost effective. Slow pyrolysis is being used for the production of charcoal, which can also be gasified to obtain hydrogen-rich gas. The short residence time pyrolysis of biomass (flash pyrolysis), at moderate temperatures, is being used to obtain a high yield of liquid products (up to 70%wt), particularly interesting as energetic vectors. Bio-oil can substitute for fuel oil-or diesel fuel-in many static applications including boilers, furnaces, engines and turbines for electricity generation. While commercial biocrudes can easily substitute for heavy fuel oils, it is necessary to improve the quality in order to consider biocrudes as a replacement for light fuel oils. For transportation fuels, high severity chemical/catalytic processes are needed. An attractive future transportation fuel can be hydrogen, produced by steam reforming of the whole oil, or its carbohydrate-derived fraction. Pyrolysis gas-containing significant amount of carbon dioxide, along with methane-might be used as a fuel for industrial combustion. Presently, heat applications are most economically competitive, followed by combined heat and power applications; electric applications are generally not competitive. © 2011 John Wiley & Sons, Ltd. Source

Discover hidden collaborations