Abstract: Soil organic carbon (SOC) plays a key role in soil
fertility, hydrology, contaminants control and acts as a sink or source
of terrestrial carbon content that can affect the concentration of
atmospheric CO2. SOC supports the sustainability and quality of
ecosystems, especially in semi-arid region. This study was
conducted to determine relative importance of 13 different
exploratory climatic, soil and geometric factors on the SOC contents
in one of the semiarid watershed zones in Iran. Two methods
canonical discriminate analysis (CDA) and feed-forward back
propagation neural networks were used to predict SOC. Stepwise
regression and sensitivity analysis were performed to identify
relative importance of exploratory variables. Results from sensitivity
analysis showed that 7-2-1 neural networks and 5 inputs in CDA
models output have highest predictive ability that explains %70 and
%65 of SOC variability. Since neural network models outperformed
CDA model, it should be preferred for estimating SOC.
Abstract: The empirical mode decomposition (EMD) represents any time series into a finite set of basis functions. The bases are termed as intrinsic mode functions (IMFs) which are mutually orthogonal containing minimum amount of cross-information. The EMD successively extracts the IMFs with the highest local frequencies in a recursive way, which yields effectively a set low-pass filters based entirely on the properties exhibited by the data. In this paper, EMD is applied to explore the properties of the multi-year air temperature and to observe its effects on climate change under global warming. This method decomposes the original time-series into intrinsic time scale. It is capable of analyzing nonlinear, non-stationary climatic time series that cause problems to many linear statistical methods and their users. The analysis results show that the mode of EMD presents seasonal variability. The most of the IMFs have normal distribution and the energy density distribution of the IMFs satisfies Chi-square distribution. The IMFs are more effective in isolating physical processes of various time-scales and also statistically significant. The analysis results also show that the EMD method provides a good job to find many characteristics on inter annual climate. The results suggest that climate fluctuations of every single element such as temperature are the results of variations in the global atmospheric circulation.
Abstract: In this paper, study on carbonation process of several types of advanced plasters on lime basis is presented. The movement of carbonation head was measured by colorimetric method using phenolphtalein. The rate of carbonation was accessed also by gravimetric method. Samples of studied materials were placed into the climatic chamber for simulation of environment with high concentration of CO2. The particular samples were on all lateral sides and on the bottom side provided by epoxy resin in order to arrange 1-D transport of CO2 into the studied samples. The carbonation rates of particular materials pointed to the time dependence of diffusion process of CO2 for all the studied plasters. From the quantitative point of view, the carbonation of advanced modified plasters was much faster than for the reference lime plaster, what is beneficial for the practical application of the tested newly developed materials.
Abstract: Climate change is a cumulative change in weather
patterns over a period of time. Trend analysis using non-parametric
Mann-Kendall test may help to determine the existence and
magnitude of any statistically significant trend in the climatic data.
Another index called Sen slope may be used to quantify the
magnitude of such trends. A toolbar extension to ESRI ArcGIS
named Arc Trends has been developed in this study for performing
the above mentioned tasks. To study the temporal trend of
meteorological parameters, 32 years (1971-2002) monthly
meteorological data were collected for 133 selected stations over
different agro-ecological regions of India. Both the maximum and
minimum temperatures were found to be rising. A significant
increasing trend in the relative humidity and a consistent significant
decreasing trend in the wind speed all over the country were found.
However, a general increase in rainfall was not found in recent years.
Abstract: In this paper, an attempt has been made to obtain nonsensitive
solutions in the multi-objective optimization of a
photovoltaic/thermal (PV/T) air collector. The selected objective
functions are overall energy efficiency and exergy efficiency.
Improved thermal, electrical and exergy models are used to calculate
the thermal and electrical parameters, overall energy efficiency,
exergy components and exergy efficiency of a typical PV/T air
collector. A computer simulation program is also developed. The
results of numerical simulation are in good agreement with the
experimental measurements noted in the previous literature. Finally,
multi-objective optimization has been carried out under given
climatic, operating and design parameters. The optimized ranges of
inlet air velocity, duct depth and the objective functions in optimal
Pareto front have been obtained. Furthermore, non-sensitive solutions
from energy or exergy point of view in the results of multi-objective
optimization have been shown.
Abstract: The basis of examines is survey of 500 in the years
2002-2010, which was selected according to homogeneity of land
cover and where 1090 revenues were evaluated. For achieved yields
of winter wheat is obtained multicriterial regression function
depending on the major factors influencing the consumption of
nitrogen. The coefficient of discrimination of the established model is
0.722. The increase in efficiency of fertilization is involved in supply
of organic nutrients, tillage, soil pH, past weather, the humus content
in the subsoil and grain content to 0.001 mm. The decrease in
efficiency was mainly influenced by the total dose of mineral
nitrogen, although it was divided into multiple doses, the proportion
loamy particles up to 0.01 mm, rainy, or conversely dry weather
during the vegetation. The efficiency of nitrogen was found to be the
smallest on undeveloped soils and the highest on chernozem and
alluvial soils.
Abstract: Facing the concern of the population to its environment and to climatic change, city planners are now considering the urban climate in their choices of planning. The urban climate, representing different urban morphologies across central Bangkok metropolitan area (BMA), are used to investigates the effects of both the composition and configuration of variables of urban morphology indicators on the summer diurnal range of urban climate, using correlation analyses and multiple linear regressions. Results show first indicate that approximately 92.6% of the variation in the average maximum daytime near-surface air temperature (Ta) was explained jointly by the two composition variables of urban morphology indicators including open space ratio (OSR) and floor area ratio (FAR). It has been possible to determine the membership of sample areas to the local climate zones (LCZs) using these urban morphology descriptors automatically computed with GIS and remote sensed data. Finally result found the temperature differences among zones of large separation, such as the city center could be respectively from 35.48±1.04ºC (Mean±S.D.) warmer than the outskirt of Bangkok on average for maximum daytime near surface temperature to 28.27±0.21ºC for extreme event and, can exceed as 8ºC. A spatially disaggregation of urban thermal responsiveness map would be helpful for several reasons. First, it would localize urban areas concerned by different climate behavior over summer daytime and be a good indicator of urban climate variability. Second, when overlaid with a land cover map, this map may contribute to identify possible urban management strategies to reduce heat wave effects in BMA.
Abstract: This paper presents the climatic range calculations for
comfort evaporative cooling for Tehran. In this study the minimum
climatic conditions required to achieve an appropriate comfort zone
will be presented.
Physiologically uncomfortable conditions in arid climates are
mainly caused by the extreme heat and dryness. Direct evaporative
cooling adds moisture to the air stream until the air stream is close to
saturation. The dry bulb temperature is reduced, while the wet bulb
temperature stays the same. Evaporative cooling is economical,
effective, environmentally friendly, and healthy.
Comfort cooling by direct evaporative cooling (passive or fan
forced) in the 35. 41 N (such as Tehran) latitude requires design
wet-bulb temperature not over 25.4 C. Evaporative cooling outside
this limit cannot achieve the required 26.7 ET, and is recommended
for relief cooling only.
Abstract: This study investigated climatic factors associated
with influenza cases in Southern Thailand. The main aim for use
regression analysis to investigate possible causual relationship of
climatic factors and variability between the border of the Andaman
Sea and the Gulf of Thailand. Southern Thailand had the highest
Influenza incidences among four regions (i.e. north, northeast, central
and southern Thailand). In this study, there were 14 climatic factors:
mean relative humidity, maximum relative humidity, minimum
relative humidity, rainfall, rainy days, daily maximum rainfall,
pressure, maximum wind speed, mean wind speed, sunshine duration,
mean temperature, maximum temperature, minimum temperature,
and temperature difference (i.e. maximum – minimum temperature).
Multiple stepwise regression technique was used to fit the statistical
model. The results indicated that the mean wind speed and the
minimum relative humidity were positively associated with the
number of influenza cases on the Andaman Sea side. The maximum
wind speed was positively associated with the number of influenza
cases on the Gulf of Thailand side.
Abstract: From a long time age, human beings have chosen their
place of residence and comfort so that those places would have
relatively ideal natural and climatic conditions. For this reason, from
the beginning, the civilizations have been formed in the susceptible
natural regions such as Mesopotamia in Iran and Nile coasts in
Egypt. Also, the core of human density has been made in the form of
an oasis in the deserts.
Regarding the formation and combination of the native
architecture in different regions of Iran, we find that different
properties of these climates have affected frequently the formation of
cities and the architectural combinations of these regions. Thus, the
precise determinations of climatic areas and attaining the climatic
properties of different regions have a great deal of importance in
presenting appropriate and compatible-with-climate designs.
Abstract: lack of convenience condition is one of the problems
in open spaces in hot and dry regions. Nowadays parks and green
landscapes was designed and constructed without any attention to
convenience condition. If this process continues, Citizens will encounter
with some problems. Harsh climatic condition decreases the
efficiency of people-s activities. However there is hard environment
condition in hot and dry regions, Convenience condition has been
provided in Iranian traditional architecture by using techniques and
methods. In this research at the first step characteristics of Iranian
garden that can effect on creating sustainable spaces were
investigated through observation method. Pleasure space in cities will
be created with using these methods and techniques in future cities.
Furthermore the comparison between Iranian garden and landscape in
today-s cities demonstrate the effectiveness of Iranian garden
characteristics on sustainable spaces. Iranian architects used simple
and available methods for creating open architectural spaces. In
addition desirable conditions were provided with taking in to account
both physically and spiritually. Parks and landscapes in future cities
can be designed and constructed with respect to architectural
techniques that used in Iranian gardens in hot and arid regions.
Abstract: This study investigated the number of Aedes larvae,
the key breeding sites of Aedes sp., and the relationship between
climatic factors and the incidence of DHF in Samui Islands. We
conducted our questionnaire and larval surveys from randomly
selected 105 households in Samui Islands in July-September 2006.
Pearson-s correlation coefficient was used to explore the primary
association between the DHF incidence and all climatic factors.
Multiple stepwise regression technique was then used to fit the
statistical model. The results showed that the positive indoor
containers were small jars, cement tanks, and plastic tanks. The
positive outdoor containers were small jars, cement tanks, plastic
tanks, used cans, tires, plastic bottles, discarded objects, pot saucers,
plant pots, and areca husks. All Ae. albopictus larval indices (i.e., CI,
HI, and BI) were higher than Ae. aegypti larval indices in this area.
These larval indices were higher than WHO standard. This indicated
a high risk of DHF transmission at Samui Islands. The multiple
stepwise regression model was y = –288.80 + 11.024xmean temp. The
mean temperature was positively associated with the DHF incidence
in this area.
Abstract: Droughts are complex, natural hazards that, to a
varying degree, affect some parts of the world every year. The range
of drought impacts is related to drought occurring in different stages
of the hydrological cycle and usually different types of droughts,
such as meteorological, agricultural, hydrological, and socioeconomical
are distinguished. Streamflow drought was analyzed by
the method of truncation level (at 70% level) on daily discharges
measured in 54 hydrometric stations in southwestern Iran. Frequency
analysis was carried out for annual maximum series (AMS) of
drought deficit volume and duration series. Some factors including
physiographic, climatic, geologic, and vegetation cover were studied
as influential factors in the regional analysis. According to the results
of factor analysis, six most effective factors were identified as area,
rainfall from December to February, the percent of area with
Normalized Difference Vegetation Index (NDVI)
Abstract: Mathematical models can be used to describe the
transmission of disease. Dengue disease is the most significant
mosquito-borne viral disease of human. It now a leading cause of
childhood deaths and hospitalizations in many countries. Variations
in environmental conditions, especially seasonal climatic parameters,
effect to the transmission of dengue viruses the dengue viruses and
their principal mosquito vector, Aedes aegypti. A transmission model
for dengue disease is discussed in this paper. We assume that the
human and vector populations are constant. We showed that the local
stability is completely determined by the threshold parameter, 0 B . If
0 B is less than one, the disease free equilibrium state is stable. If
0 B is more than one, a unique endemic equilibrium state exists and
is stable. The numerical results are shown for the different values of
the transmission probability from vector to human populations.