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[en] The difficulties in CFD analysis of indoor/outdoor environments is described in this paper and new techniques in CFD for overcoming these difficulties are developed. A 'Software Platform' is proposed that integrates various numerical analysis tools and that is able to give a complete evaluation of indoor/outdoor climates. A number of case studies on designing indoor/outdoor climates are reported based on this newly developed Software Platform
[en] This article analyzes the influence of the urban morphology on the external microclimatic conditions and the thermal comfort level in Socio Vivienda II, one of the most important low-income housing settlements in Guayaquil, Ecuador. Four stages of this urbanization were morphologically characterized to be able to develop the virtual model of the physical environment of the urbanization, which was carried out through dynamic simulation programs in order to obtain microclimatic data at different times of the year and hours of the day. This data have been calibrated with real measurements of the site, such as temperature, relative humidity, wind direction and skyfactor, during the most unfavorable weather conditions for warm weather. Among the parameters used for this study we have: solar orientation, roads sections, distances between buildings, building heights, sunlight, landscape coefficient, the size of the plots and their relations with open spaces, among others. The comfort conditions of the thermal environment were quantified in terms of the PET bioclimatic index calculated through the Rayman model where the most effective strategies could be selected to achieve comfortable environments and to evaluate the impact of the design and planning of the urban configuration.
[en] Measurements have been carried out using four types of passive detectors in four of the most popular show caves in Romania. Three types of detectors (RSKS, RadTrak and CD) were used for radon measurements and two (Raduet and CD) for thoron measurement. Activity concentrations in air were measured in the same locations for two seasons, autumn and winter. Measured values for the different caves varied between below detection limit (5 Bq m-3) and 4024 Bq m-3 for radon and from below 10 to 583 Bq m-3 for thoron. The results indicate a very good correlation between RSKS and RadTrak detectors (r = 0.96). The most significant difference between radon concentrations measured with different types of detectors (RSKS and CD) was higher than 150%. The study suggests that the activity concentration of radon in caves, measured using track detectors, could not be influenced by the type of detector used if the microclimate factor is acknowledged. (authors)
[en] This fact sheet complements the fact sheet on passive solar design, and provides information on how sunlight, weather patterns, and microclimates affect the performance of solar energy systems and designs
[en] Aim of study: The study aimed to characterise variation in structural attributes of vegetation in relation to variations in topographic position using LIDAR data over landscapes. Area of study: The study was conducted in open canopy eucalypt-dominated forest (Richmond Range National Park-RRNP) and closed canopy subtropical rainforest (Border Ranges National Park-BRNP) in north-eastern New South Wales, Australia. Material and Methods: one metre resolution digital canopy height model (CHM) was extracted from the LIDAR data and used to estimate maximum overstorey height and crown area. LIDAR fractional cover representing the photosynthetic and non-photosynthetic component of canopy was calculated using LIDAR points aggregated into 50 m spatial bins. Potential solar insolation, Topographic Wetness Index (TWI), slope and the elevation were processed using LIDAR derived digital elevation models. Main results: No relationship was found between maximum overstorey height and insolation gradient in the BRNP. Maximum overstorey height decreased with increasing insolation in the RRNP (R2 0.45). Maximum overstorey height increased with increasing TWI in the RRNP. Average crown area decreased with increasing insolation in both study areas. LIDAR fractional cover decreased with increasing insolation (R2 0.54), and increased with increasing TWI (R2 0.57) in the RRNP. Research highlights: The characterization of structural parameters of vegetation in relation to the variation of the topography was possible in eucalyptus dominated open canopy forest. No reportable difference in variation of structural elements of vegetation was detected with topographic variation of subtropical rainforest. (Author)
[en] Validated and reliable measurement data are the foundation of any scientific report, especially in research fields that describe environmental stressors. In order to yield a trustworthy interpretation of environmental 'events' monitored and explored by measuring ionising radiation, it is necessary to obtain accurate data on the local background radiation in the environment where research is conducted. Values of the measured ambient dose rate equivalent H*(10), an operational quantity for environmental monitoring used to characterise local natural background radiation, greatly depend on the geographic placement, geological composition, and urbanisation of the very location of the measurement. IMROH has designed and installed a measuring station within the research polygon Sumbar with the aim to establish it as a reference measuring station for local background ionising radiation for all future research regarding ionising radiation and its naturally, as well as accidentally, caused oscillations in the environment. Discrepancy in the H*(10) values between the two measuring locations is fully justified considering the fact that the Institute is located in an urban surrounding burdened by nearly every possible pollutant as well as buildings and is characterised by a specific city microclimate, while Sumbar is an ecologically untouched area, hunting grounds, and natural habitat mainly unaffected by modern life. Furthermore, knowing the H*(10) values at a remote and 'unpolluted' location in real time (interactive communication with the measuring station) also enables a significantly faster regulatory reaction in cases of potential radiological accidents. (author).
[en] China's climate differs greatly in various regions, ranging from severe cold to hot and arid to humid. This has significant influences on energy efficient building design strategies and energy use. Solar radiation data from 123 measuring stations were used to propose a map indicating the solar radiation climates in China. A cluster analysis was adopted to identify the prevailing solar climates using the monthly average daily clearness index, K t, as climatic variable. Five major solar climates were identified with annual average K t ranging from 0.3 in the Sichuan Basin to 0.65 in the north and northwest regions. The solar climates were compared with the more widely used general (thermal) climates (severe cold, cold, hot summer and cold winter, mild and hot summer and warm winter) and the major topography (basin, plain and plateau), and implications for building designs were briefly discussed
[en] Plant productivity in protected cultivation is highly influenced by air temperature and humidity. The conditions relating to the moisture content of the air in protected plant cultivation are preferably defined by vapour pressure deficit (VPD), which describes the difference between the maximal and actual water vapour pressure (kPa). VPD is widely used as the parameter describing the climate conditions favourable for the development of fungal diseases and for highlighting conditions unfavourable for plant development. In protected cultivation, both the air temperature and the humidity are influenced by heating systems, and one such system is a heat accumulator, which may store the excessive heat produced during the day by converting the solar energy inside the plastic tunnel, and using it when plant heating is required. The tunnel equipped with a heat accumulator maintained an optimal level of humidity for a longer period, and significantly reduced the time of excessive air humidity. The longest time with an optimal VPD was recorded in August in a tunnel with an accumulator – 30.5% of total time vs. 22.3% of time for control tunnel. The highest difference of total time where the VPD was too low (below 0.2 kPa) was recorded in July – 12.4% of time in a tunnel with an accumulator vs. 39.1% of time for control tunnel. The highest difference of total time with an excessive VPD (over 1.4 kPa) was recorded in May – 12.1% of time in a tunnel with an accumulator vs. 17.9% of time for control tunnel. However, a situation beneficial for plant growth occurred every month during the investigated season.
[en] To evaluate demographical dynamics of yew populations in the Iberian Mediterranean mountains in order to assess population trends and a hypothetical natural regeneration of the species. : Ayllón Mountain Range, Eastern end of Central Mountain Range, Spain. A field survey was conducted on three yew groves, taking data of altitude, orientation, companion woody species, UTM coordinates, height, perimeter (at breast height, 120cm) and sex. Individuals were classified in four age groups, considering height and trunk perimeter: AgeGroup1, Seedling; AgeGroup2, Juvenile; AgeGroup3, Adult and AgeGroup4, Old. Finally Recruitment rate was calculated for each population. Surveyed yew populations include more than 1600 trees, showing elevated Recruitment rates, which indicates that there are more seedling and juvenile individuals (Group1 and Group2) than adult and old ones (Group3 and Group4). Surveyed yew populations show vigorous regeneration. These results lead us to reconsider the relictic character assigned to the species in the Iberian Mediterranean mountains.