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The present article utilizes wind measurements from three buoys data collection stations in Ionian Sea to study the wind speed and power characteristics using the Weibull shape and scale parameters. Specifically, the site dependent, annual, and monthly mean patterns of mean wind speed, Weibull parameters, frequency distribution, most probable wind speed, maximum energy carrying wind speed, wind power density and wind energy density characteristics have been analyzed. The Weibull distribution was found to represent the wind speed distribution with more than 90% accuracy, in most of the cases. Moreover, the correlation between the percentages of times the wind speed was above cut-in-speed and the measured mean wind speed for the three selected sites, as the correlation between the aforementioned percentages and the scale parametercwere examined and were found linear. At all these sites, no definite increasing or decreasing trends in annual mean wind speed values could be detective over the data reporting period. The mean values of wind speed, scale parameter, most probable wind speed, maximum energy carrying wind speed, wind power and wind energy density values showed higher values during winter time and lower in summer time in Pylos and Zakynthos. Moreover, Pylos and Zakynthos were found to be the best sites from wind power harnessing point of view. [ABSTRACT FROM AUTHOR]

Motivated by the international tendency to improve the urban microclimate, minimize building energy consumption and improve air quality, this paper carries out a literature review of the Urban Heat Island (UHI) effect throughout the world with the main goal of reporting its intensity and understand its determining factors. Items reported for each study include: time duration, location and population of cities studied, number and type of data collecting stations, descriptive temperature measurements estimated and warming trend per unit of time. Variables that appear to influence the UHI included latitude and elevation; climate characteristics, surface morphology, vicinity to bodies of water, distance from industrial sites, urbanization, vegetation cover, land usage, presence of impervious surfaces, presence of urban canyons, building density, distribution and consumption of heating or cooling energy, building ventilation as well as road traffic intensity and urban air pollution. Difficulties arose from the fact that data were collected under different conditions and protocols and the conclusions have mostly local validity while the size and significance of the UHI was inversely associated with inhomogeneity adjustments. All in all, observations point to significantly higher urban temperatures than the surrounding rural environment with temperature records suggesting an upwards trend in both urban and rural measurements, strongly related to urbanization and vegetation. The UHI intensity was usually significant during warm periods and increased in both minimum and maximum temperatures. It was concluded that the UHI effect varied as to the city size, land use, topographic factors, vegetation, urbanization, and industrialization, season of the year and time of day as well as the prevailing meteorological conditions. [ABSTRACT FROM AUTHOR]

During the last years much research has taken place about urban heat island (UHI) effects, mainly concentrated in big cities with an extended gap for the smaller. The aim of the paper is to present the analysis results of an urban heat island research taking place in a small city of Western Greece, Agrinio. The specific research target was to validate the presence of the UHI, measure its intensity and determine the parameters that correlate with the appearance of the UHI. A network of air temperature sensors was developed in 8 different places in the city and measurements were recorded every 10 minutes for a period of 6 months. Data from a meteorological station were also collected for the same period. Results show that the city of Agrinio presents strong UHI intensities during the night with high values up to 6°C and a mean of 3.82 °C. During the daytime, cool island effect is also observed for about 35% of day duration. Temperature differences appear to be strongly correlated with the dominating wind speed in the city since air plays an important role in urban ventilation and creates more homogeneous temperatures in urban spar. [ABSTRACT FROM AUTHOR]

The design, installation and operation of an Automatic Weather Station (AWS) are described and analysed in the present paper. This station of high endurance is easy to be installed and capable for long-time operation without significant problems. The metadata of the station which are the characteristics of the instruments, electronic logic control and datalogging systems are described in detail, according to the Guides of the World Meteorological Organization (WMO). Moreover, a computer controlled environment is designed and implemented, with capabilities of data acquisition and control with flexible and high performing software and hardware capabilities. The AWS can easily communicate, so directly as remotely, with some modifications and both possibilities are examined in detail. Finally, an evaluation procedure is presented and analyzed, while the obtained results are used for testing the system. The evaluation depicted the unique and well established characteristics of the system and proved its potential application to meteorological data collection and calculation. [ABSTRACT FROM AUTHOR]

The present study deals with various techniques aiming primarily to improve the environmental and microclimatic quality of urban areas, and, secondly, to minimize the energy consumption in the buildings' sector based mainly on bioclimatic principles and criteria in the same area. The selected techniques, which include the re-use of treated wastewater effluents using the wastewater treatment plan, as well as solar passive heating/cooling techniques, have' been applied in a specific urban area located in Patras, a large city of western Greece. The application of the treated wastewater effluents re-use in urban areas is possible through the combined reuse of the treated municipal wastewater effluents indoors for domestic use, as well as for irrigating plants in outdoor spaces. One building of the area was selected as representative, and its thermal behavior was simulated and analyzed primarily in its existing situation, and, furthermore, after using several passive cooling techniques, such as the installation of a green roof system, the use of insulating materials in the external walls and roof, the insertion of an atrium, night ventilation techniques, etc. The obtained results showed that with regards to the cooling load, the application of night ventilation and a green roof system provided the higher energy saving, while with respect to the heating load, the more efficient improvements were the insulation on the building's external walls and roof. [ABSTRACT FROM AUTHOR]

Bamboo is known as a sustainable alternative for green building design, and it has been tied culturally to some regions around the world. However, bamboo's structural strength for different design scenarios needs more investigation before it is widely adopted. Timber and bamboo have similar mechanical properties, but the latter is a repaid, renewable, sustainable, disaster-resilient system and is versatile, which has more advantages for construction purposes. Natural bamboo and its derivatives have been considered as a high-demand green and environmentally responsible alternative construction material, and this interest is increasing globally. Because of the rapid growth rate and large developing area, it is more useable than the limited timber resource. However, natural bamboo has an anisotropic and nonhomogeneous material property, which varies in multiple directions. There is limited engineering data and investigation of bamboo material and its use in and impact on construction. In this study, three different bamboo models were analyzed by Strand7; each of them had different features in structure and in the major construction material. A new model was proposed by improving the three given structures and was maximized in the mechanical capacity. Some design guidelines were proposed based on the analysis and comparison of different bamboo structures. The model will replace natural bamboo with bamboo scrimber, which is an engineered bamboo derivative that has more uniform material properties. [ABSTRACT FROM AUTHOR]