Abstract: A total of 33,680 nuclear power plants (NPPs) workers were monitored and recorded from 1990 to 2007. According to the record, the average individual radiation dose has been decreasing continually from it 3.20 mSv/man in 1990 to 1.12 mSv/man at the end of 2007. After the International Commission on Radiological Protection (ICRP) 60 recommendation was generalized in South Korea, no nuclear power plant workers received above 20 mSv radiation, and the numbers of relatively highly exposed workers have been decreasing continuously. The age distribution of radiation workers in nuclear power plants was composed of mainly 20-30- year-olds (83%) for 1990 ~ 1994 and 30-40-year-olds (75%) for 2003 ~ 2007. The difference in individual average dose by age was not significant. Most (77%) of NPP radiation exposures from 1990 to 2007 occurred mostly during the refueling period. With regard to exposure type, the majority of exposures were external exposures, representing 95% of the total exposures, while internal exposures represented only 5%. External effective dose was affected mainly by gamma radiation exposure, with an insignificant amount of neutron exposure. As for internal effective dose, tritium (3H) in the pressurized heavy water reactor (PHWR) was the biggest cause of exposure.
Abstract: Vapour recompression system has been used to
enhance reduction in energy consumption and improvement in
energy effectiveness of distillation columns. However, the effects of
certain parameters have not been taken into consideration. One of
such parameters is the column heat loss which has either been
assumed to be a certain percent of reboiler heat transfer or negligible.
The purpose of this study was to evaluate the heat loss from an
ethanol-water vapour recompression distillation column with
pressure increase across the compressor (VRCAS) and compare the
results obtained and its effect on some parameters in similar system
(VRCCS) where the column heat loss has been assumed or neglected.
Results show that the heat loss evaluated was higher when compared
with that obtained for the column VRCCS. The results also showed
that increase in heat loss could have significant effect on the total
energy consumption, reboiler heat transfer, the number of trays and
energy effectiveness of the column.
Abstract: Characterized as rich mineral substances, low
temperature, few bacteria, and stability with numerous implementation
aspects on aquaculture, food, drinking, and leisure, the deep sea water
(DSW) development has become a new industry in the world. It has
been report that marine algae contain various biologically active
compounds. This research focued on the affections in cultivating
Sagrassum cristaefolium with different concentration of deep sea
water(DSW) and surface sea water(SSW). After two and four weeks,
the total phenolic contents were compared in Sagrassum cristaefolium
culturing with different ways, and the reductive activity of them was
also be tried with potassium ferricyanide. Those fresh seaweeds were
dried with oven and were ground to powder. Progressively, the marine
algae we cultured was extracted by water under the condition with
heating them at 90Ôäâ for 1hr.The total phenolic contents were be
executed using Folin–Ciocalteu method. The results were explaining
as follows: the highest total phenolic contents and the best reductive
ability of all could be observed on the 1/4 proportion of DSW to SSW
culturing in two weeks. Furthermore, the 1/2 proportion of DSW to
SSW also showed good reductive ability and plentiful phenolic
compositions. Finally, we confirmed that difference proportion of
DSW and SSW is the major point relating to ether the total phenolic
components or the reductive ability in the Sagrassum cristaefolium. In
the future, we will use this way to mass production the marine algae or
other micro algae on industry applications.
Abstract: The production of activated carbon from low or zero cost of agricultural by-products or wastes has received great attention from academics and practitioners due to its economic and environmental benefits. In the production of bamboo furniture, a significant amount of bamboo waste is inevitably generated. Therefore, this research aimed to prepare activated carbons from bamboo furniture waste by chemical (KOH) activation and determine their properties and adsorption capacities for water treatment. The influence of carbonization time on the properties and adsorption capacities of activated carbons was also investigated. The finding showed that the bamboo-derived activated carbons had microporous characteristics. They exhibited high tendency for the reduction of impurities present in effluent water. Their adsorption capacities were comparable to the adsorption capacity of a commercial activated carbon regarding to the reduction in COD, TDS and turbidity of the effluent water.
Abstract: In this present study, experimental work was
conducted to study the effectiveness of newly innovated steel-CFRP
composite (CFRP laminates sandwiched between two steel strips) as
stirrups. A total numbers of eight concrete beams were tested under
four point loads. Each beam measured 1600 mm long, 160mm width
and 240 mm depth. The beams were reinforced with different shear
reinforcements; one without stirrups, one with steel stirrups and six
with different types and numbers of steel-CRFR stirrups. Test results
indicated that the steel-CFRP stirrups had enhanced the shear
strength capacity of beams. Moreover, the tests revealed that steel-
CFRP stirrups reached to their ultimate tensile strength unlike FRP
stirrups which rupture at much lower level than their ultimate
strength as werereported in various researches.
Abstract: Tourism is a phenomenon respected by the human communities since a long time ago. It has been evoloving continually based on a variety of social and economic needs and with respect to increasingly development of communication and considerable increase of tourist-s number and resulted exchange income has attained much out come such as employment for the communities. or the purpose of tourism development in this zone suitable times and locations need to be specified in the zone for the tourist-s attendance. One of the most important needs of the tourists is the knowledge of climate conditions and suitable times for sightseeing. In this survey, the climate trend condition has been identified for attending the tourists in Isfahan province using the modified tourism climate index (TCI) as well as SPSS, GIS, excel, surfer softwares. This index evoluates systematically the climate conditions for tourism affairs and activities using the monthly maximum mean parameters of daily temperature, daily mean temperature, minimum relative humidity, daily mean relative humidity, precipitation (mm), total sunny hours, wind speed and dust. The results obtaind using kendal-s correlation test show that the months January, February, March, April, May, June, July, August, September, October, November and December are significant and have an increasing trend that indicates the best condition for attending the tourists. S, P, T mean , T max and dust are estimated from 1976-2005 and do kendal-s correlation test again to see which parameter has been effective. Based on the test, we also observed on the effective parameters that the rate of dust in February, March, April, May, June, July, August, October and November is decreasing and precipitation in September and January is increasing and also the radiation rate in May and August is increasing that indicate a better condition of convenience. Maximum temperature in June is also decreasing. Isfahan province has two spring and fall peaks and the best places for tourism are in the north and western areas.
Abstract: The leaching behavior and structure of Li2O-CeO2- Fe2O3-P2O5 glasses incorporated with simulated high level nuclear wastes (HLW) were studied. The leach rates of gross and each constituent element were determined from the total weight loss of the specimen and the leachate analyses by inductively coupled argon plasma spectroscopy (ICP). The gross leach rate of the 4.5Li2O- 9.7CeO2-34.7Fe2O3-51.5P2O5 glass waste form containing 45 mass% simulated HLW is of the order of 10
Abstract: This article presents the results using a parametric approach and a Wavelet Transform in analysing signals emitting from the sperm whale. The extraction of intrinsic characteristics of these unique signals emitted by marine mammals is still at present a difficult exercise for various reasons: firstly, it concerns non-stationary signals, and secondly, these signals are obstructed by interfering background noise. In this article, we compare the advantages and disadvantages of both methods: Auto Regressive models and Wavelet Transform. These approaches serve as an alternative to the commonly used estimators which are based on the Fourier Transform for which the hypotheses necessary for its application are in certain cases, not sufficiently proven. These modern approaches provide effective results particularly for the periodic tracking of the signal's characteristics and notably when the signal-to-noise ratio negatively effects signal tracking. Our objectives are twofold. Our first goal is to identify the animal through its acoustic signature. This includes recognition of the marine mammal species and ultimately of the individual animal (within the species). The second is much more ambitious and directly involves the intervention of cetologists to study the sounds emitted by marine mammals in an effort to characterize their behaviour. We are working on an approach based on the recordings of marine mammal signals and the findings from this data result from the Wavelet Transform. This article will explore the reasons for using this approach. In addition, thanks to the use of new processors, these algorithms once heavy in calculation time can be integrated in a real-time system.
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: Brucellosis is a zoonotic disease; its symptoms and appearances are not exclusive in human and its traditional diagnosis is based on culture, serological methods and conventional PCR. For more sensitive, specific detection and differentiation of Brucella spp., the real time PCR method is recommended. This research has performed to determine the presence and prevalence of Brucella spp. and differentiation of Brucella abortus and Brucella melitensis in house mouse (Mus musculus) in west of Iran. A TaqMan analysis and single-step PCR was carried out in total 326 DNA of Mouse's spleen samples. From the total number of 326 samples, 128 (39.27%) gave positive results for Brucella spp. by conventional PCR, also 65 and 32 out of the 128 specimens were positive for B. melitensis, B. abortus, respectively. These results indicate a high presence of this pathogen in this area and that real time PCR is considerably faster than current standard methods for identification and differentiation of Brucella species. To our knowledge, this study is the first prevalence report of direct identification and differentiation of B. abortus and B. melitensis by real time PCR in mouse tissue samples in Iran.
Abstract: It has been always observed that the effectiveness of
MIS as a support tool for management decisions degenerate after
time of implementation, despite the substantial investments being
made. This is true for organizations at the initial stages of MIS
implementations, manual or computerized. A survey of a sample of
middle to top managers in business and government institutions was
made. A large ratio indicates that the MIS has lost its impact on the
day-to-day operations, and even the response lag time expands
sometimes indefinitely. The data indicates an infant mortality
phenomenon of the bathtub model. Reasons may be monotonous
nature of MIS delivery, irrelevance, irreverence, timeliness, and lack
of adequate detail. All those reasons collaborate to create a degree of
degeneracy. We investigate and model as a bathtub model the
phenomenon of MIS degeneracy that inflicts the MIS systems and
renders it ineffective. A degeneracy index is developed to identify
the status of the MIS system and possible remedies to prevent the
onset of total collapse of the system to the point of being useless.
Abstract: This paper investigates experimentally and
analytically the torsion behavior of steel fibered high strength self
compacting concrete beams reinforced by GFRP bars. Steel fibered
high strength self compacting concrete (SFHSSCC) and GFRP bars
became in the recent decades a very important materials in the
structural engineering field. The use of GFRP bars to replace steel
bars has emerged as one of the many techniques put forward to
enhance the corrosion resistance of reinforced concrete structures.
High strength concrete and GFRP bars attract designers and
architects as it allows improving the durability as well as the esthetics
of a construction. One of the trends in SFHSSCC structures is to
provide their ductile behavior and additional goal is to limit
development and propagation of macro-cracks in the body of
SFHSSCC elements. SFHSSCC and GFRP bars are tough, improve
the workability, enhance the corrosion resistance of reinforced
concrete structures, and demonstrate high residual strengths after
appearance of the first crack. Experimental studies were carried out
to select effective fiber contents. Three types of volume fraction from
hooked shape steel fibers are used in this study, the hooked steel
fibers were evaluated in volume fractions ranging between 0.0%,
0.75% and 1.5%. The beams shape is chosen to create the required
forces (i.e. torsion and bending moments simultaneously) on the test
zone. A total of seven beams were tested, classified into three groups.
All beams, have 200cm length, cross section of 10×20cm,
longitudinal bottom reinforcement of 3
Abstract: Supercritical carbon dioxide (SC-CO2) was used as a
solvent to extract oil from wheat bran. Extractions were carried out in a
semi-batch process at temperatures ranging from 40 to 60ºC and
pressures ranging from 10 to 30 MPa, with a carbon dioxide (CO2)
flow rate of 26.81 g/min. The oil obtained from wheat bran at different
extraction conditions was quantitatively measured to investigate the
solubility of oil in SC-CO2. The solubility of wheat bran oil was found
to be enhanced in high temperature and pressure. The composition of
fatty acids in wheat bran oil was measured by gas chromatography
(GC). Linoleic, palmitic, oleic and γ-linolenic acid were the major
fatty acids of wheat bran oil. Tocopherol contents in oil were analyzed
by high performance liquid chromatography (HPLC). The highest
amount of phenolics and tocopherols (α and β) were found at
temperature of 60ºC and pressure of 30 MPa.
Abstract: Methane is the second most important greenhouse gas
(GHG) after carbon dioxide. Amount of methane emission from
energy sector is increasing day by day with various activities. In
present work, various sources of methane emission from upstream,
middle stream and downstream of oil & gas sectors are identified and
categorised as per IPCC-2006 guidelines. Data were collected from
various oil & gas sector like (i) exploration & production of oil & gas
(ii) supply through pipelines (iii) refinery throughput & production
(iv) storage & transportation (v) usage. Methane emission factors for
various categories were determined applying Tier-II and Tier-I
approach using the collected data. Total methane emission from
Indian Oil & Gas sectors was thus estimated for the year 1990 to
2007.
Abstract: For the first time since 1940 and presentation of
theodorson-s theory, distribution of thrust, torque and efficiency
along the blade of a counter rotating propeller axial fan was studied
with a novel method in this research. A constant chord, constant
pitch symmetric fan was investigated with Reynolds Stress
Turbulence method in this project and H.E.S. method was utilized to
obtain distribution profiles from C.F.D. tests outcome. C.F.D. test
results were validated by estimation from Playlic-s analytical method.
Final results proved ability of H.E.S. method to obtain distribution
profiles from C.F.D test results and demonstrated interesting facts
about effects of solidity and differences between distributions in front
and rear section.
Abstract: In this paper we propose a blind algorithm for peakto- average power ratio (PAPR) reduction in OFDM systems, based on selected mapping (SLM) algorithm as a distortionless method. The main drawback of the conventional SLM technique is the need for transmission of several side information bits, for each data block, which results in loss in data rate transmission. In the proposed method some special number of carriers in the OFDM frame is reserved to be rotated with one of the possible phases according to the number of phase sequence blocks in SLM algorithm. Reserving some limited number of carriers wont effect the reduction in PAPR of OFDM signal. Simulation results show using ML criteria at the receiver will lead to the same system-performance as the conventional SLM algorithm, while there is no need to send any side information to the receiver.
Abstract: A liquid curved jet has many applications in different
industrial and engineering processes, such as the prilling process
for generating small spherical pellets (fertilizer or magnesium). The
liquids used are usually molten and contain small quantities of
polymers and therefore can be modelled as non-Newtonian liquids. In
this paper, we model the viscoelastic liquid jet by using the Oldroyd-
B model. An asymptotic analysis has been used to simplify the
governing equations. Furthermore, the trajectory and a linear temporal
stability in the presence of gravity and rotation have been determined.
Abstract: The proper selection of the AC-side passive filter
interconnecting the voltage source converter to the power supply is
essential to obtain satisfactory performances of an active power filter
system. The use of the LCL-type filter has the advantage of
eliminating the high frequency switching harmonics in the current
injected into the power supply. This paper is mainly focused on
analyzing the influence of the interface filter parameters on the active
filtering performances. Some design aspects are pointed out. Thus,
the design of the AC interface filter starts from transfer functions by
imposing the filter performance which refers to the significant current
attenuation of the switching harmonics without affecting the
harmonics to be compensated. A Matlab/Simulink model of the entire
active filtering system including a concrete nonlinear load has been
developed to examine the system performances. It is shown that a
gamma LC filter could accomplish the attenuation requirement of the
current provided by converter. Moreover, the existence of an optimal
value of the grid-side inductance which minimizes the total harmonic
distortion factor of the power supply current is pointed out.
Nevertheless, a small converter-side inductance and a damping
resistance in series with the filter capacitance are absolutely needed
in order to keep the ripple and oscillations of the current at the
converter side within acceptable limits. The effect of change in the
LCL-filter parameters is evaluated. It is concluded that good active
filtering performances can be achieved with small values of the
capacitance and converter-side inductance.
Abstract: Many studies have been conducted for derivation of
attenuation relationships worldwide, however few relationships have
been developed to use for the seismic region of Iranian plateau and
only few of these studies have been conducted for derivation of
attenuation relationships for parameters such as uniform duration.
Uniform duration is the total time during which the acceleration is
larger than a given threshold value (default is 5% of PGA). In this
study, the database was same as that used previously by Ghodrati
Amiri et al. (2007) with same correction methods for earthquake
records in Iran. However in this study, records from earthquakes with
MS< 4.0 were excluded from this database, each record has
individually filtered afterward, and therefore the dataset has been
expanded. These new set of attenuation relationships for Iran are
derived based on tectonic conditions with soil classification into rock
and soil. Earthquake parameters were chosen to be
hypocentral distance and magnitude in order to make it easier to use
the relationships for seismic hazard analysis. Tehran is the capital
city of Iran wit ha large number of important structures. In this study,
a probabilistic approach has been utilized for seismic hazard
assessment of this city. The resulting uniform duration against return
period diagrams are suggested to be used in any projects in the area.
Abstract: Wireless LAN (WLAN) access in public hotspot areas
becomes popular in the recent years. Since more and more multimedia
information is available in the Internet, there is an increasing demand
for accessing multimedia information through WLAN hotspots.
Currently, the bandwidth offered by an IEEE 802.11 WLAN cannot
afford many simultaneous real-time video accesses. A possible way to
increase the offered bandwidth in a hotspot is the use of multiple access
points (APs). However, a mobile station is usually connected to the
WLAN AP with the strongest received signal strength indicator (RSSI).
The total consumed bandwidth cannot be fairly allocated among those
APs. In this paper, we will propose an effective load-balancing scheme
via the support of the IAPP and SNMP in APs. The proposed scheme is
an open solution and doesn-t need any changes in both wireless stations
and APs. This makes load balancing possible in WLAN hotspots,
where a variety of heterogeneous mobile devices are employed.