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Background: Back injury in nurses is one of the most common health problems. The chronic low back pain leads to several problems including disability, daily activities, physical and emotional problems and decreasing quality of life. The purpose of this study was to assess the quality of life of nursing staff with chronic nonspecific low back pain in Yazd, Iran. Materials and Methods: This study was a descriptive-analytic study. A total of 119 nurses were selected with nonrandom purposive sampling method. Health-related quality of life of the participants was assessed using the 36-item short-form health survey questionnaire (SF-36) and analyzed through SPSS software version 20 by appropriate statistical tests. Results: This study showed that there were significant differences between the quality of life of nursing staff with chronic low back pain and Iranian normal population in all aspects (P < .0001). It was revealed that only in the area of physical function there was a significant relationship between age and the quality of life (P < .0001). Conclusion: The results confirmed the effect of income on dimensions such as physical role, bodily pain, mental health, and social function.

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Background: Socio demographic characteristics of nurses who work in hospitals may impact on their quality of life. This study aimed to assess the relationship between quality of life of nursing staff with chronic nonspecific low back and their socio demographic characteristics. Materials and Methods: This study was a cross section study. A total of 119 nurses were participated in this study. The 36-item short-form health survey questionnaire (SF-36) was used to assess Health Related Quality of Life (HRQOL) of the participants. SPSS software version18 was applied to analyze data by appropriate statistical tests. Results: Totally 119 nurses including 93 female (78.1%) were participated in the study. The study showed that there was a significant relationship between age and physical function (P < 0.0001). Also there was significant relationship between income and physical role (P < 0.0001) as well as bodily pain (P = 0.015), mental health (P = 0.015), and social function (P = 0.03. ( Conclusions: The socio demographic characteristics of nurses could be considered while their QOL are assessed.

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Inheritance of several yield-based drought resistance indices was studied by a halfdiallel method using seven winter wheat varieties. The parental lines were such chosen as to represent a broad range of drought stress resistance. The experiment was conducted in a split-plot design at the research farm, Faculty of Agriculture, Zanjan University, Iran, in 1998. Irrigated vs. rainfed regimes were considered as the main plots. The F1 hybrids and parental varieties constituted the subplots. From the grain yield data, some drought resistance indices such as geometric mean productivity (GMP), mean productivity (MP), standard superiority measure (SP), stress susceptibility index (SSI), stress tolerance index (STI), superiority measure (P), and tolerance (TOL) were calculated. Genetic components of variance and heritabilities were estimated using Gardner and Eberhart’s Method 3, Model II. Significant differences among parents and F1s were observed for all indices except for SSI and TOL. Significant general combining abilities (GCA) were obtained for GMP, MP, P, SP, STI, and TOL but not for SSI. Therefore, except for SSI, other indices could be regarded as heritable. The specific combining ability (SCA) effects were also highly significant for GMP, MP, P, SP, and STI. However, additive variances were more important than dominance ones. Narrow-sense heritability estimates were very low for SSI, low for TOL, but moderate for GMP, MP, P. SP, and STI. Thus selection based on the latter indices could be more promising than on SSI and TOL. It seems that SP and STI might be better yield-based drought resistance indices to be employed in plant breeding programs, because of their moderate narrow-sense heritabilities and the inherent ability of selecting high yielding genotypes in either stressed or non-stressed conditions.

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Limited water for irrigation and the coincidence of early growth of sugar beet (Beta vulgaris L.) with the late growth of winter cereals in the Northeast (NE) of Iran, force farmers, to allocate their limited irrigation water to the cereal crops and thus their sugar beet crop is subjected to an early water stress. Finding cultivars which are able to withstand early water stress without a significant yield reduction is critical to the farmers’ economy. This study was conducted over a two-year period (1998 and 1999) to evaluate the response of nine sugar beet genotypes to drought stress and to determine the crop traits associated with drought resistance. The results showed that stomatal conductance, leaf-air temperature difference and proline accumulation were associated with levels of water stress in sugar beet genotypes. Among these indices, leaf-air temperature difference was a more precise parameter to measure. A negative correlation between Δ T (leaf -air temperature) and stomatal conductance was found. The correlation coefficients for 1998 and 1999 were -0.87 and -0.58, respectively. There was a positive correlation between Δ T and proline accumulation in sugar beet genotypes. The correlation coefficients for the 1998 and 1999 experiments were 0.61 and 0.49, respectively. The shoot: root ratio (S:R) measured at the end of the stress period showed that genotypes with a lower S:R often had a greater stomatal conductance. In general, genotypes with a lower S:R at the end of the stress period usually had a greater root dry weight. The correlation coefficients of S:R with root dry weight at the end of the stress period were -0.96 and -0.65 for 1998 and 1999, respectively.

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During the collection of Ichneumonidae from West Azarbaijan province in the northwest of Iran in 2019, we collected a specimen belonging to the subfamily Tersilochinae and identified it as Aneuclis pumilus (Holmgren). This is a new record of this species for the Iranian fauna. A checklist of all known Iranian species of the subfamily is provided.

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In this paper, we propose a novel method for fully automatic detection and tracking of human heads and faces in video sequences. The proposed algorithm consists of two modules: a face detection module and a face tracking module. The Detection module, detects the face region and approximates it with an ellipse at the first frame using a modified version of AdaBoost cascaded classifier. The detection module is capable of considering the 2-D head pose rotation. The tracking module utiliyes a combination of deformable mesh energy minimization and feature matching approaches. In order to track a face, features are extracted in the face region to tessellate the human face with triangular unstructured meshes. For tracking a mesh, it is necessary to define mesh energies including internal and external energies. We have used new energy definitions for both the internal and the external energies which can accurately track rigid and non-rigid motions of a face and facial features at subsequent frames. We tested the proposed method with different video samples like cluttered backgrounds, partial illumination variations, put on glasses, and 2-D and/or 3-D rotating and translating heads. The experimental results showed that the algorithm is rotation insensitive and has high accuracy, stability and also has convergence for face detection and tracking.

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Although in recent two decades, the concept of Dielectric Barrier Discharges (DBDs) have been developed in ozone production well, air pollution control, plasma screens and control of chemical, and biological and medical processes, employment of this concept for high voltage applications to improve insulation performance as an alternative to the pressurized gas-insulated systems (GIS) utilizing SF6, is still in research phase. In this paper, the enhancement of insulation performance using DBD and with increasing charge densities on the barrier surfaces in uniform electric filed has been statically modeled. This means that the dynamics of the development of space charges and the manner they sit on the barrier surfaces are ignored and only DBD concepts considering different amounts of surface charges on the barrier surfaces are evaluated. Also the influence of various parameters, such as permeability of the dielectric material, its thickness, and length of air gap, on the enhancement of insulation performance are evaluated. Then an algorithm for the formation of space charges, settling on the barrier surfaces and electric filed modification in the air gap for three types of voltage including DC, AC and lightning impulse, is simulated and evaluated using MATLAB. In this modeling, dielectrics are considered as non-insulating with some electrical conductivity.

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Species of the subfamily Diplazontinae (Hym.: Ichneumonidae) were studied in West Azarbaijan province (Northwest of Iran). The specimens were collected using Malaise traps, during 2019–2020. Five species belonging to three genera were collected and identified. One species, Homotropus riedeli Johansson, 2020 was a new record for Iran as well as Asia. The distribution range of this species extends from Sweden to the north-west of Iran. A checklist is being compiled for 27 known Iranian species of this subfamily. In addition, a distribution map based on the recorded areas for each species within the Iranian provinces has been provided. We proposed a new direction for future biodiversity inventories of this subfamily in Iran.

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- Several numerical methods have been emerged to analyze the engineering problems. Boundary Element Method (BEM) is an important method for solving the partial differential equation in engineering problems. The Poison equation is an applicable equation in various engineering problems. General solution of this equation is obtained based on BEM by definition of the two integrals on the domain boundaries, and one integral in the internal domain which is a drawback for this method. To remove this disadvantage, Dual Reciprocity Method (DRM) is suggested. For example, in analysis of the welding heat transfer problems in transient zone where not homogeneous part is involved time dependent terms, is solved by this method. The calculation of the welding zone temperature history is a significant step for the thermal loading and residual stress analysis of the process. In this work, welding temperature history is obtained using the DRM. The Method and its theory are explained. Then, the code validation is carried out by common heat transfer problems. The welding temperature history is studied for a specific case by the created code. Because of the method simplicity and low time and error in computation process, the application of DRM is recommended.

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An ideal fusion method preserves the spectral information in fused image without spatial distortion. The PCA is believed to be a well-known pan-sharpening approach and being widely used for its efficiency and high spatial resolution. However, it can distort the spectral characteristics of multispectral images. The current paper tries to present a new fusion method based on the same concept. In the conventional standard PCA method, PCA transform is applied to spectral bands of multispectral images, but we applied the PCA transform to pixel blocks instead. Since PCA coefficients are extracted from statistical properties of the image, it is more consistent with type and texture of remotely sensed image compared to other kernels such as wavelets. After that, a new hybrid algorithm is proposed which uses both the spatial PCA and the spectral PCA method to improve the quality of the merged images. Visual and statistical analyses show that the proposed algorithm clearly improves the merging quality in terms of RASE, ERGAS, SAM, correlation coefficient and UIQI; compared to fusion methods such as IHS, Brovey, PCA, HPF, and HPM.

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The fusion of valuable spectral and spatial features can significantly improve the performance of high resolution hyperspectral images classification. In this paper, we propose a spectral and spatial feature extraction method based on discriminant analysis. To increase the class discrimination, we maximize the between-class scatters and minimize the within-class scatters. To include the spatial information in the feature extraction process, we estimate the spatial scatters in a spatial neighborhood window with multi-scale fashion. We compare our proposed method, which is called spectral-spatial discriminant analysis (SSDA), with some spatial-spectral feature extraction methods included original spectral bands plus Gabor filters, gray level co-occurance matrix (GLCM), and morphology profiles and also with some popular spectral feature extraction methods such as nonparametric weighted feature extraction (NWFE) and locality preserving projection (LPP). Moreover, we compare SSDA with some recently proposed spectral-spatial classification approaches. The experimental results on two real hyperspectral images show the good performance of SSDA compared to the competitor methods.

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The purpose of this study is thermo-economic analysis of a combined fuel cell and micro gas turbine power plant cycle for using in small scale CHP systems. Since the fuel cell is the main source of power generation in hybrid systems, in this study, complete electrochemical, thermal and thermodynamic calculations are performed to obtain more accurate results; and unlike most studies, the cell temperature is not assumed constant. The performance analysis of the hybrid system shows that increasing the pressure and air to fuel ratio, causes to loss of electrical efficiency and increase in the electricity price because of reduction in cell and turbine inlet gas temperatures. The other results of this study show that considering the economic life of the system, making use of this type of hybrid systems is economical and generates less electricity price in comparison with micro gas turbine.

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Due to some practical limitations, it is not possible to adopt images which have both high spectral and spatial resolutions. Image fusion is one of the methods that utilizes image supplementary information, to the effect that it combines the spatial information of images with high spatial resolution, By the use of these spectral information of the images with high spectral resolution, one can creates an image that has high spatial and spectral resolutions simultaneously. Current methods and algorithms of image fusion are not efficient enough to combine new satellite images due to some changes in these satellites; therefore, providing new methods of image fusion is of paramount significance for the above-mentioned satellites. Image fusion methods should desirably maintain the spectral and spatial information of the original images. In the present study, a new algorithm was introduced to combine the spatial information of the IKONOS images with the spatial resolution of 1m with the spectral information of the SPOT images with the spatial resolution of 20m. This algorithm is in the feature-level and is based on the Retinal Model. Other existent fusion models such as IHS, HPF, PCA, Wavelet and the hybrid Wavelet-PC were also applied to these images. The results of the spatial and spectral assessments of the combined images indicated that the spectral and spatial information of the proposed method are better. One of the major advantages of this method is that there is no need for resampling, which is a must in other methods.

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The consumption expenditure is a key element of macroeconomic analyses, which accounts for considerable share of aggregate demand in Iran. Any effort for forecasting the future consumption trend is of special importance for policy-makers. In this paper, we specify a consumption model relying on theoretical basics in order to obtain desirable forecasts. On the basis of Duesenberry and Friedman consumption theories, we use genetic algorithm (GA) and particle swarm optimization (PSO) algorithm to simulate Iranians consumption during 1973-2009. Then we select the superior model in terms of prediction power criteria and forecast consumption until 2025. According to the results, the PSO algorithm is efficient and accurate in forecasting consumption; and consumption behavior of Iranians is consistent with Duesenberry theory. In addition, the simulations by exponential consumption model indicate increasing average propensity to consume until 2025.  

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A method based on Machine Vision System (MVS) is hereby employed to evaluate grape drying through an assessment of the fruit’s shrinkage and quality during the dehydration. Experimental data as well as captured images are obtained at an air velocity of 1.4 m s^-1 and different drying temperatures (50, 60, 70ºC). The results indicated the effect of temperature on the moisture content, shrinkage and color changes. The moisture content along with color changes (ΔE) were modeled and linear regressions applied to correlate the fruit’s shrinkage as well as color features to the moisture content. The results obtained, displayed that there existed good linear relationships between the fruit’s moisture content, and shrinkage as well as color. The results also revealed that the moisture content vs. quality of the grape could be online evaluated through machine vision during the drying process.

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This article investigates experimental study of the flow field on a blunt airfoil. For this purpose, PIV technique based on instantaneous flow structures is used in order to view and two dimensional investigation of flow field around unmodified and blunt airfoil and at different times. This study is performed on flows at very low Reynolds number(Reynolds number lower than 4500). This flow regime is very similar to dominant condition on micro air vehicles (MAVs). In order to validate the method used in this study, flow field around cylinder is considered and in continue, instantaneous and mean velocities fields, streamlines and mean vortices field around unmodified and blunt airfoils are obtained. The results show that there are prominent differences on the structure of wake around airfoils and sizes of separation region for blunt and simple airfoils. Meanwhile separation of the flow for both blunt and simple airfoils at this very low Reynolds number, is occurred at angle of attack 5 (at low angle of attack). Also generation of vortex at wake region and their position and circulation at different times, are discussed.

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In this study evaporation of biodiesel droplet under different operating conditions is investigated. The model is a common droplet vaporization model for multicomponent fuels. In this model, gas phase quasi-steady equations are solved analytically and energy and species transport equation in liquid phase are solved numerically. The sub-models are modified to consider high pressure effects. Peng-Robinson equation of state is used for gas phase and phase equilibrium is determined using fugacity. Effects of pressure on the thermophysical and transport properties of gas phase are considered. Five biodiesel with different composition are studied. These biodiesel have different composition of methyl esters. Biodiesel composition has little effects on droplet lifetime and maximum difference is about 20%. It is observed that increasing ambient temperature leads to decrease in droplet lifetime and increases temperature gradient inside droplet. Ambient pressure has different effects on droplet vaporization behavior at different ambient temperature. At lower temperature environment, increasing of pressure increases the droplet lifetime while at higher temperatures droplet lifetime first increases and then decreases with pressure. Increasing initial velocity of droplet reduces the droplet lifetime. Results show that at high pressures, droplet temperature reach to values near to critical temperature and accuracy of quasi-steady approximation decreases. Radius of vapor influenced sphere increases with temperature and decreases with pressure.

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Premature rupture of steel structures in seismic Northridge connections led to investigate the connection performance against the forces of earthquake, many researchers are studied. The performance of these joints and connections against forces caused by various kinds of earthquakes, accurate determination of the used parameters and bearing capacity parameters of connections. The fact that no two earthquakes are similar adds emphasis to adopting a coordinated approach for testing different structural elements. These requirements results in developing standard loading histories called loading protocols. Today, the ever-increasing development of using steel in the construction industry in Iran has become clearly evident. Considering the fact that Iran is an earthquake-prone country, identifying the behavior of these structures against earthquake forces assumed importance. Seven, twelve and twenty-story steel moment frames were selected as research models, and after preparing a proper list of accelerograms recorded in the course of earthquakes occurred in Iran during 1978-2007 , the seismic demands applied to structural components were estimated. Regarding the catastrophic aftermath of earthquakes, having a reliable approach to assess the seismic demands proper to the region of interest seems inevitable. The scope of this study is to provide a list of far-field seismic records applicable to 2-D nonlinear time history analyses in Iran. To do that a set of 2000 seismic records from Iran's seismic records database has been investigated based-on their characteristics, amongst are focal distance, magnitude, rupture mechanism, frequency content, and soil profile, resulting in compilation of a list of 20 accelerograms for the purposes of the two dimensional and non-linear analyses in Iran. The proposed accelerograms portray as a true area’s seismic movement as possible. In continuation of study, the final coefficient of scale for the accelerograms for the steel moment frames is calculated with a point to point differentiation method in periodic intervals corresponding to each frame. For the coefficient of scale, an operation conducted in a way that for each accelerogram in the average spectrum, an appropriate response is determined. Time-history dynamic analysis has been carried out by using the list of proposed accelerogram records aiming at preparing the loading protocol of steel moment connections, and the rainflow cycle counting technique has been employed to determine damage parameters for research models. Considering the fact that strength and deformation capacities depends on cumulative damage in earthquake engineering, every component has a permanent memory of past damaging events and at any instance in time it will remember all the past excursions (or cycles) that have contributed to the deterioration in its state of health. A loading protocol is developed specifically for this purpose.For developing the loading protocol of moment-resisting connections, the time history is analyzed using the proposed set of accelerograms recorded, and by applying the method of rainflow cycle counting, damage parameters are determined for the research models. The number of damaging cycles, total deformation range, deformation range and peak of deformation range are the employed parameters, which will be evaluated and compared for all the layers of the research models. Afterwards, statistical estimations are performed on damage parameters and target values are established. Finally, a loading protocol is recommended for moment-resisting joints commonly used in Iran which has the capacity of being applied to the considered structural elements under one general state.

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Ultrasonic waves have variety of applications in bio field. The most important applications are diagnosis and treatment of diseases, drug delivery, cell separation and cell study. Passing ultrasonic waves through tissues and organs, which creates heat, bubble, stress and vibration, can result in chemical reactions, physical and biological changes. What exacerbated the researchers' scientific activities in this area is reducing the harmful effects and increasing the usefulness of this beneficial tool. In current research, the interaction of two nonlinear phenomena, acoustic streaming due to passing ultrasonic waves through bio-fluid and non-Newtonian viscosity is studied numerically. Taking into account nonlinear effects of ultrasonic field, continuity, momentum and state equations are used. In this paper, parametric effects of wall impedance, inlet flow velocity and non-Newtonian viscosity models on acoustic streaming are investigated. Results indicate influence of inlet speed on acoustic streaming velocity magnitude and its ineffectiveness on acoustic streaming profile. By increasing wall impedance, acoustic streaming magnitude decreases. This reduction is more intensive for non-Newtonian fluid. Considering non-Newtonian viscosity model for bio-fluid leads to velocity changes near boundaries, while it has less influence at domain middle.

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Cell injection system in medicine used to inject the materials into the cells. The injection system consists of Injector and rotating plate. The controller sets height, position and orientation of the rotating plate. The proposal of this article is to replace SCARA robot injection tool and it included ability in desired position tracking and applied to time-varying force. In recent articles the control system applies to the rotating plate of Cells and this method can cause the damaging risk. The proposed method is fixed plate and to increase the success rate, the robot had been controlled. The parameters of environmental models are estimated by nonlinear proposed models and by using the recursive method, the minimum of squares errors will be optimal. The voltage strategy can control robot actuators. This method is simpler and free from the manipulator dynamics. In all recent studies, the impedance control is based on the torque control method and the proposed method of this article is applying the impedance control using voltage control. The robust adaptive impedance controller is designed in the presence of uncertainties. The simulation's results demonstrate desired performance of the proposed method