In the paper a Chinese remainder theorem based new bio-cryptography scheme is proposed, which is designed in cascade structure and adopts an error correction technique to improve the performance, to tackle the problem...
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In the paper a Chinese remainder theorem based new bio-cryptography scheme is proposed, which is designed in cascade structure and adopts an error correction technique to improve the performance, to tackle the problems in secret sharing based methods. In key retrieval, it greatly brings down the number of operations, avoids exhaustive calculation of tarsus, reduces the computation and improves the efficiency of the algorithm. Finally the software system based the iris features, verifies the new biocryptography scheme with cascade structure, experimental results show that this scheme has better practicability and stability, which can resolve big computation problem in retrieving secret.
CDM(Climatological Dispersion Model) is a classical air pollution model based on the Gaussian approximation and aimed at computing the long term(monthly and annual) averages of air pollution concentration in an ur...
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CDM(Climatological Dispersion Model) is a classical air pollution model based on the Gaussian approximation and aimed at computing the long term(monthly and annual) averages of air pollution concentration in an urban *** concentration at any number of receptors is computed as the result of up to 2500 aerial and 200 point sources on flat *** can compute two pollutants at the same time and has been used for both SO2 and *** order to predict the amount and dispersion rate of major air pollutants(CO,CO2,NOx and Sox) in the studied area,we use CDM during two different cold and warm seasons in four daily periods of *** modeling data were classified in two categories includes sources of dispersion such as diameter and height of stacks and climatological data such as temperature,wind speed and *** we confirmed our results with field sampling and Tecplot software.
The optimal exploitation of water from a dam reservoir requires a comprehensive knowledge of future availability of water resources. In this case the amount of water that will be available in the future is important. ...
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The optimal exploitation of water from a dam reservoir requires a comprehensive knowledge of future availability of water resources. In this case the amount of water that will be available in the future is important. Also, we need to examine the flows at the dam from a short-term perspective. This is necessary to avoid overflowing and to minimize damage. In order to facilitate forecasting of the water resources, many different techniques have been developed through the years. In this paper, using yearly data (since 1988-2007) obtained from Hydrometric station at Dez (upstream of Dez Dam), the Auto Regressive Integrated Moving average (ARIMA) model, for prediction of monthly mean inflow to Dez Dam reservoir was accomplished. On the basic of comparison the results of the model with measured data, the performance of ARIMA(1,1,0)(1,0,0)12 model is acceptable.
Along with the rapid development of computer technology and digital image processing application, words are frequently shown as images too. For little priori knowledge, blind image restoration should be used for blurr...
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Along with the rapid development of computer technology and digital image processing application, words are frequently shown as images too. For little priori knowledge, blind image restoration should be used for blurry text image. We improve the blind deconvolution algorithm, one of blind image restoring methods, combining the text-specific bimodal characteristic about histogram with blind deconvolution method by means of probability and statistics theory. The improved algorithm increases the computation speed and optimizes the visual effect of recovery text image largely. It is verified that the advanced image restoration algorithm has better recovery capacity and certain practical value through the analysis and simulation of some typical experiments.
Standalone photovoltaic(SAPV) systems are widely used in remote areas after development of photovoltaic cell industry in recent *** as the load and insolation conditions vary the efficiency of the PV system decreases....
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Standalone photovoltaic(SAPV) systems are widely used in remote areas after development of photovoltaic cell industry in recent *** as the load and insolation conditions vary the efficiency of the PV system decreases.A maximum power point tracker(or MPPT) is a high efficiency DC to DC converter which functions as an optimal electrical load for a photovoltaic(PV) cell,most commonly for a solar panel or array,and converts the power to a voltage or current level which is more suitable to whatever load the system is designed to drive.A PV cell has an exponential relationship between current and voltage,and the maximum power point(MPP) occurs at the knee of the *** this work,a MPPT has been proposed which works in conjunction with a power electronic converter to shift the operating point to obtain maximum power from a PV Panel with load and insolation conditions *** first tracks the MPP and sets the operating *** modeling and simulation has been done in Simulink software available with *** efficiency of the proposed MPPT has also been *** has been shown how the efficiency of the system increases when we use MPPT for a resistive load.
In this paper, numerical simulation of three-dimensional flow field of a vertical-type liquid-continuous impinging stream reactor(VLISR) was carried out by FLUENT software, its fluid movement regulation was studied, a...
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In this paper, numerical simulation of three-dimensional flow field of a vertical-type liquid-continuous impinging stream reactor(VLISR) was carried out by FLUENT software, its fluid movement regulation was studied, and the distributions of pressure and velocity were analyzed. This method is convenient and easy with a reliable result compared to engineering practice. In addition, the change of horizontal velocity under different positions was investigated. Numerical study results showed that the pressure distribution was symmetrical to the axial of impinging stream reactor. In the area of pivoted axle and guide cylinder, the pressure gradient was the maximum,showing strong pressure fluctuation. The maximum velocity,which was 0.82 m/s, was found near the impeller. The results may provide fundamentals for hydraulic cell disruption, and data for further optimization and improvement of vertical-type liquid-continuous impinging stream reactors.
IEC 61850-6 defines Substation Configuration description Language(SCL) for Intelligent Electronic Devices(IEDs) in a *** SCL file containing a large amount of IED data is always too big to be processed by common means...
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IEC 61850-6 defines Substation Configuration description Language(SCL) for Intelligent Electronic Devices(IEDs) in a *** SCL file containing a large amount of IED data is always too big to be processed by common means,and the standard itself is so complicated that makes IED configuration *** solve this problem,a specially designed configurator should be introduced to improve performance and provide a user-friendly *** paper analyzes SCL file's structure,types and object *** presents IED configuration's design principles and the software architecture,as well as the key technologies and the *** introducing an improved XML parser and graphical user interface in the configurator,users can configure IED in a more efficient and effective *** IED configurator was developed in C#,the test result indicated its resource utilization was confined to a reasonable level and its visual interface helps users to browse and configure SCL files in a convenient way.
Aiming at the construction technique and economical issues of large-span steel tube arches cross double width highway. Based on the actual situation of the bridge across the Huang Yan highway on the Bao-Xi railway cor...
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Aiming at the construction technique and economical issues of large-span steel tube arches cross double width highway. Based on the actual situation of the bridge across the Huang Yan highway on the Bao-Xi railway corridor, the full support openings construction method is adopted and firstly set up the beam then the part of arch. Combination of construction site conditions and design load requirements, the stents and alcoves calculation model are set up by the large finite element software ANSYS and its deformation and stress were analyzed and checked The results show that the stents and strander beams are meet the requirements. And the construction methods do not affect traffic, carrying capacity is strong, good stability, suitable for girder and arch construction crossing big barriers and traffic is heavy.
Climate change in world is always one of the most important topics in water resources. Weather parameters including precipitation, monthly Temperature and relative humidity forecasting could be practically useful in m...
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Climate change in world is always one of the most important topics in water resources. Weather parameters including precipitation, monthly Temperature and relative humidity forecasting could be practically useful in making decisions, risk management and optimum usage of water resources. These three parameters have undeniable effects on hydrological cycle, production of crops products cycle, water usage specifically agricultural usage, people activities and the environments. Time series analysis has two goals, perception or modeling random mechanism and prediction of future series quantities according to the past. In this research 20 years statistics of relative humidity and monthly average temperature and precipitation of Abadeh Station have used by ITSM time series analysis software. According to the ARIMA model, ACF, PACF and evaluation of all eventual samples, precipitation model: ARIMA (0 0 1) (1 1 1)12 and monthly average temperature : ARIMA (2 1 0) (2 1 0)12 and relative humidity : ARIMA (2 1 1) (1 1 0)12 were obtained.
Although there is growing evidence that metals can be toxic to various aquatic species,there is still insufficient knowledge to integrate this information in environmental risk assessment *** this study,we have invest...
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Although there is growing evidence that metals can be toxic to various aquatic species,there is still insufficient knowledge to integrate this information in environmental risk assessment *** this study,we have investigated bioaccumulation and effects of nickel on mortality and growth of Artemia urmiana and Artemia *** LC 50 in 24 h of *** and *** exposed to nickel were 0.0072,0.0114 mg/l *** indicates that the mean length of animals in(0.001,0.002 and 0.003 mg/l) Ni on first,fifth,eleventh and seventeenth days of life significantly decreases in comparison with control groups(p<0.05).Bioaccumulation of Ni in the same concentration,after 24 h in nauplius and also in adults of *** and *** were significantly higher than of the control groups(P < 0.05).Both species accumulate nickel in their *** *** is more resistant to the heavy metals.
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