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A time-domain approach is presented to calculate electromagnetic fields inside a large Electromagnetic Pulse (EMP) simulator. This type of EMP simulator is used for studying the effect of electromagnetic pulses on electrical apparatus in various structures such as vehicles, a reoplanes, etc. The simulator consists of three planar transmission lines. To solve the problem, we first model the metallic structure of the simulator as a grid of conducting wires. The numerical solution of the governing electric field integral equation is then obtained using the method of moments in time domain. To demonstrate the accuracy of the model, we consider a typical EMP simulator. The comparison of our results with those obtained experimentally in the literature validates the model introduced in this paper.

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Water erosion causes a series of on-site as well as off-site damages and problems on natural ecosystem. These damages include soil and nutrient loss and finally loss of productivity which causes costs to the society. So, this study attempts to quantify the economic value of soil productivity conservation as one of the important functions of rangelands vegetation and its economic cost by productivity losses. The soil loss amounts were obtained from integrated Geographic Information System (GIS) and map of erosion vulnerable areas using RUSLE model. Supplementary data such as soil nutrients (NPK) valuated from the measurement plots of a portable rainfall simulator (E65). Field plots were constructed to measure soil nutrients and soil loss from different soil types with different resistance to erosion. Rainfall simulation was carried out in three sites on the basis of geology map and different resistance to erosion. Nine experimental unit plots (1*1 m) were used to correlate nutrient loss to sediment losses. Assuming that nutrient loss by erosion could be replaced by fertilizers, economic cost of major nutrients estimated by market prices of fertilizers. Results showed that mean annual soil loss using RUSLE was 27.44 t ha^-1 y^-1 ranging from 0.0 to 996.06 t ha^-1 y^-1. Also, 114.17 kg ha^-1 y^-1 of N, P, K elements were lost in 2010 due to soil erosion in the degraded rangelands which costs (738944 Rial) 71.5 US$ ha^-1y^-1. Total economic cost of soil nutrient loss in 94978.6 ha of the rangelands of Nour-rud watershed basin, was estimated 70×10^{^}9 Rial (6.8×10⁶ US$). The maximum annual cost of soil nutrient loss was estimated in the "TRujs" geological formation (1.23×10⁶ US$) consisting of "gray shale, silt, sandstone, conglomerate" and the least cost belonged to the "Jl1" geological formation (0.916*10⁶ US$) which consists of "thin gray dolomite limestone". In economic terms there was a direct relationship between soil nutrient loss and its economic cost.

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The runoff generation and soil erosion in the Kechik Watershed, Golestan Province, was assessed, using a designed and constructed portable rainfall simulator. Treatments were applied on different land-uses, slopes and aspects as the most influential factors. Results showed that land-use significantly affected runoff generation (13.35 l, 6.9 l, and 4.12 l, respectively for agriculture, forest and rangeland uses), however slope (7.7 l for Class I; 9.23 l for Class II) and aspect (8.52 l for the northern aspects; 8.32 l for the southern aspects) did not have significant influence. All factors, significantly altered sediment concentration (Agriculture 9.6 g l^-1, forest 8.24 g l^-1, and rangeland 5.26 g l^-1; slope class I 6.6 g l^-1 and slope class II 8.7 g l^-1; northern aspect 8.7 g l^-1, and southern aspect 6.9 g l^-1). Agricultural fields generated the highest runoff and sediment under simulated rainfalls. Rangeland and forest did not have significant runoff generation and sediment concentration. Results showed that land-use management, especially in terms of agriculture, could not only hamper current erosion, but reduced further advancement of this encroaching phenomenon.

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To achieve a reasonable level of precision in tractor-based field operations, a tractor operator has to guide accurately, monitor and control both the tractor and the attached implement. Since guidance is the most time consuming task among the others, researchers have attempted to automate the guidance task. However, the use of automatic guidance and control in agricultural applications is not always appropriate. Transportation of the vehicle on a public road is an example of this. Some researchers, therefore have focused on Vision-Aided methods to give some guidance aid to the driver rather than on eliminat-ing the driver. To investigate the accuracy of such methods, a Vision-Aided tractor guid-ance belt-type simulator was developed. An experimental prototype of the simulator was constructed. To evaluate the prototype, a completely randomized factorial experiment was conducted with forward speed, heading angle, and camera tilt angle being the major factors under investigation. The simulator performed satisfactorily at 5 and 7km/h and mean deviations of 1.14 and 2.31cm were obtained respectively.

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The first performance of the home is to create shelter, a haven which provides peace for inhabitants. Village House is a safe and reliable "inner place" against "external environment" with the extent of the wild nature. Therefore, the first performance of the home is primary need of rural people. The formation of the house is affected by a variety of environmental factors of three surrounding environments which in different species are formed based on special regional and local materials of the area by natives of the area.
In fact, the most important characteristic of rural homes, especially (Gilan) is simplicity and harmony with the natural environment surrounding them, in such a way that, a building not only is not a waste element that is added to the environment, but is risen from its surroundings, and the stability is reached due to its exposure.
conditions, not only has led to a different appearance of the buildings in the area, but due to the abundant use of wood and plant fibers in the building, and special properties of these materials, methods of construction in Gilan is distinct from other parts of Iran. Studying traditional methods of construction in Gilan to identify a species of "architecture in harmony with nature", Leads us to full interaction of man and the surrounding environment, that all of them indicate Intelligent human knowledge in time with the technical limitations of construction, and the sense of respect for nature.
As architectural elements and building components, all in order to build a dynamic architecture in this particular area of the building not only by benefiting from natural curran in the summer leads to climate comfort in the spring and summer, but in winter with a layer of semi-enclosed elements, such as Faken, reduces the amount of heat exchange between indoor and the surrounding environment.
Accordingly, the logic of construction and materials are selected based on potential and natural resources in the region and leads to use the local materials, combining fences, columns, headers and wooden beams and flowers used in walls, decoration by flowers and roof with four slopes are considered as individual components of a vernacular architecture, that in the passage of time has damaged stability of the building like natural disasters such as floods and earthquakes, which is considered as an effective factor among the indicator species in each region.
In Gilan geographic reach, which air humidity and rainfall is very high, rural housing should not only meet human needs related to shelter, but must include climatic comfort relatively. As such, residential building must be constructed in such a way that reduxes moisture in the environment over human tolerance to have proper temperature and humidity conditions. In this area, because of moderate temperatures in many times of the year, reduced air humidity provides comfort because discomfort in summer is felt due to high relative humidity of the air at all times a day. So, wind can move easily in order to repel moisture around the body and the human environment.
The relationship between the building and the environment is considered as the most obvious aesthetic features of Gilan rural buildings, which is rooted in geography, cultural issues and style life in Gilan. The lack of tangible boundary between inside and outside has given to it different effects compared with the central regions of Iran.
The houses of the area are generally built either in the direction of East or with a little rotation from East to South and this is due to the use of maximum sunlight and air flow. The used materials are indigenous as other rural areas of Gilan and available materials are used. The walls in this region are mainly the combination between the "Chineei" 1 "Zegali" 2 and completely Zegali. Because of the abundance of straw in the area,”Kolosh”3 is used as Zegal in the walls. In fact, all the art of living in the Gilan plain can be summarized in coping with difficult climatic conditions such as annual rainfall by almost 1280 mm, the humidity between 70 to 90 percent and temperature fluctuation between * 20 and * 37 .
In different parts of the plains of Gilan where the climatic characteristics cause a particular kind of architecture, outward-oriented architecture, regardless of the contradictions and complexities of construction technique, and variations in the utilization of local and available materials, we're seeing similarities in the scheme of this type of architecture, the majority of similarities in these buildings include:
The existence of the porch and hallway in a four-walled building that most biological environments.
Get the limited space and enclosed in the heart of the monument and surrounded by a hallway and porch for winter time.
Multi-layer being the main views and spaces with a maximum porosity in the outermost level.
The height of the residential parts of the getting off the ground.
Placement comfy wooden stairs without an intermediary style that the relationship between the grounds and the supply of housing.
The mass use of plant and wood materials and uncoated amood.
The four characteristics of the dwellings of the plain Gila can be distinguished from includes the following items:
I. The height of the Earth's surface to protect it against moisture in the ground.
II. Fans with steep slope.
III. The existence of one or more of the aisle and the porch in views.
IV. Construction of houses based on vertical plan common build dwellings that central in Iran (Making room on the horizontal inner courtyard) is different
This research seeks to analyze the body of one of the native habitat of the index and the geographical boundaries of Gilan plain areas exclusively to the analysis method - described by Sachs and method of analysis techniques - modeling Builder designed with energy simulation software to evaluate a sample of their unit. Accordingly, the use of library studies on the described manner, the morphology of Gilan and provide basic concepts on completion of organ literature as early as the theoretical basis. The use of macro and micro-scale field studies of settlements to analyze the climate and the physical samples for example in the form of software modeling background design study builder and table Sachs contributed.
At the end of these studies show, as well as comfort in Gilan native settlements for rural residents and require the passage of time has been granted, Today, the role of climate change in temperate climate and wet in macro and micro scale habitable space And general changes in consumer materials residential structures in rural areas, the use of natural energy role in natural ventilation by not using energy artifact(Cooling and heating) is not possible and the combination of the two systems, natural and artificial energy is not inevitable, even in native settlements.
Research purposes
I. Clear analysis of how the formation of a native settlement on the centrality of body structure and climate
II. Assessment components and sub a native settlement in the description of the concepts of sustainable Sachs
III. Analysis of large-scale example of architecture in warm and cold seasons the energy simulation software

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Aims: This study aimed to investigate the effect of different planting plans, especially trees with varying characteristics of branch and leaf structure, height, canopy diameter, and density, leaf shape, and size, and compare the cooling effect under similar conditions to a suitable planting plan for maximum productivity. 

Methods: The data collection method in this field and library research and the analysis method used are simulations, and the findings and comparison of results are quantitative and qualitative. Vegetation information of the site in the first stage is harvested, and the current situation is simulated, and its impact is determined. Then two new planting plans with the same amount of greenery in the current situation are designed and manufactured in the environment, and the results are compared.

Findings: The simulation results show that group planting mode is completely similar conditions in terms of plant species and the number of trees 0.85 ° C reduces the average air temperature compared to the linear planting mode and the biggest difference is in the average radiant temperature, which is more than 3 (3.18) ° C There is a temperature difference between group planting mode compared to linear planting mode and group planting mode has a lower average radiant temperature.

Conclusion: This study revealed the effect of the group planting plan factor, despite creating a full shade of trees and reducing the shading area of ​​trees, improved the PMV thermal comfort index and improved environmental variables.

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The preliminary design of multistage axial compressor requires a vast number of design variables and limitations, the simultaneous investigation of which needs a complicated design program. This study provides a new algorithm by the use of combining multi-variable/multi-objective optimizations, meanline simulator and preliminary design program. On the one hand the two-layer optimization is used to consider all design variables and on the other the design limitations are put into the cost function together with surge margin and efficiency. The comparison of the results with the NASA transonic eight-stage compressor shows the ability of the new algorithm to achieve a compressor with better performance and lower weight.

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In this paper, a real time simulator of the engine-generator for a series hybrid electric bus is designed which can be used for hardware in the loop testing of the hybrid bus control unit. As an important step for designing a hardware in the loop simulator, messages that the engine and generator receive from the vehicle control unit are identified. Design of the simulator is based on these received messages and dynamic behavior of the components. Since the engine and generator receive speed or torque commands from the vehicle control unit, two PID controllers are designed to bring the engine or generator to the desired speed. By applying appropriate inputs, different modes of operation of the diesel-generator is simulated including the soft start process and steady state operation. For a simulator, the ability to interface with a real hardware requires a real time simulation. To do so, the design process is implemented in LabVIEW environment and results show that the designed simulator gives responses close to real test results and it is suitable for developing the hybrid vehicle control unit.

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Drowsy driving is a main cause of severe accidents. Drowsiness is responsible for 30% to 37% of fatal road accident in Iran. In this paper, driver drowsiness is detected based on features related to the steering wheel angle and the lateral position of the vehicle. Data from the vehicle and the virtual road are used to extract drowsiness features. Experimental results using a driving simulator are presented. Participants were 21 to 28 year-old males with a high tendency to sleep (Epworth Sleepiness Scale≥10). The subjects had to drive a lane keeping scenario on a long and monotonous virtual road in both drowsy and alert states. The drowsiness criteria are validated with Karolinska Sleepiness Scale (KSS) and video rating based on KSS measurements. The results illustrate that the phase diagram of the steering wheel angle (Ellipse criterion), the standard deviation of the steering wheel angle, and the mean and the standard deviation of the lateral position of the vehicle are highly correlated with drowsiness. The accuracy of the diagnosis was 77% for the Ellipse criterion, 76% for the standard deviation of the steering wheel angle, 67% for the standard deviation of the lateral position, and 65% for the mean value of the lateral position.

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Due to the complexity in the control system of hybrid vehicles, the electronic control units should go through extensive testing before getting installed in a prototype vehicle. In the first stages of the development process, Hardware-in-the-Loop (HiL) simulation can not be performed because the hardware components of the vehicle are not yet available. In this case, Model-in-the-loop (MiL) simulation is used which couples the designed control software with an environment simulation with no need for a special hardware. In this paper, the MiL simulation is introduced for verification of the vehicle control software in a series hybrid electric bus. To do so, considering the dynamic behavior of various components of the vehicle, a simulator of the hybrid bus is designed by going through with the input/outputs of the vehicle control software. Using the designed test bench, the user can act as a real driver and experience different driving regimes and analyze the control software commands. In the designed simulator, all subsystems are simulated separately in LabVIEW environment and real-time simulation is achieved with an acceptable error. Therefore, it can be used in a HiL test bench for testing each of the vehicle components. The designed simulation model has been validated using real test results. Using that, results show that all control functions in the vehicle control software can be tested and verified with no cost and in the shortest possible time.

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This article describes the details in design and development of a satellite attitude dynamics simulator that is used to validate control algorithms, improve novel control methods, verify the operation of available actuators or sensors and exhibit the fundamentals of attitude dynamics to students or experts. This dumbbell style simulator is based on a spherical air-bearing and is able to produce a frictionless and torque-free environment for simulating spacecraft operational environment. The facility includes a variety of subsystems such as: cold-gas propulsion subsystem, inertial measurement unit, power-supply unit, on-board processor and semi-automatic mass balancing mechanism. The overall design of this system was pretty complicated especially when considering the mission requirements, operating constraints and functional limitations imposed by the ground-based simulation, thus, a detailed design procedure has been deployed and also, this procedure has been performed accurately. An explanation about dynamic equations of motion of simulator with on-off thrusters, software-based simulation, applying reliable control algorithm and balancing methodology is the next part of this article. Finally, the results of the realistic maneuvers of this satellite simulator are presented and investigated in detail.

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The attenuation of mechanical load is one of the most effective approaches in wind turbine components cost reduction, and improving the control system reduces mechanical loads with minimum effort. In modern wind turbines, electrically-excited synchronous generators are mostly applied in direct-drive structure. In current research, generator field voltage along with the blade pitch angle is employed for tower load reduction in a novel multivariable-adaptive control structure. The controller is designed based on the extracted model with aerodynamic, vibratory and electrical interactions. The centralized multivariable structure is chosen to simultaneously reduce rotor speed fluctuations and tower vibrations. Since the nonlinear wind turbine model is complex, the controller is designed via optimization process. The nonlinear aerodynamic behavior of blades influences the closed-loop performance in different operating condition; therefore controller is adapted to the condition by employing gain-scheduling method. The effects of signal noise, digital control and higher-order dynamics of electrical system might defect the closed-loop stability. The designed controller is implemented on a wind turbine simulator which includes the before-mentioned effects. By comparing the performance of the multivariable adaptive controller with a two input-one output multivariable controller, it is proven that the mechanical loads acting on tower have been greatly decreased.

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Todays, parallel robots with six degrees of freedom are widely used in motion simulation industry. Spreading application of motion simulation for different means of transportation has led to advance training in a safe way with less time and equipment cost. Mostly, the 6-UPS structure Stewart parallel manipulator is used as motion simulators due to their large workspace, rigidity and load capacity. Since the massive moving actuated prismatic joint is located between fixed and moving platforms, the dynamic performance of the mechanism is not efficient. The robot with PUS structure can be a good alternative for UPS type as its actuators are fixed to the ground. This results in lowering of the overall robot cost in addition to stiffness increase. In this paper the inverse kinematic and dynamic of a general 6-PUS robot is presented using Newton-Euler method. The theoretical dynamic model results are verified using motion analysis software. A simplified dynamic model is prepared eliminating links’ inertial terms from dynamic equation. The accuracy of the model is evaluated for different link to payload mass properties ratio. The simplified dynamic model used to improve the computational efficiency of the inverse dynamics.

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During transient phase of motor burning in an altitude test simulator, the low momentum exhaust combustion gases could not establish supersonic flow in the exhaust diffuser. This leads to a reverse flow of the exhaust gases into the vacuum chamber through the annular gap between nozzle and diffuser walls. This spoils the vacuum in the chamber and it is potentially dangerous for measurement instruments inside the vacuum chamber. In this research; at the first, the physics of the flow at initial transient phase of motor burning is investigated numerically and the backflow phenomenon is illustrated. Then, the influences of backflow arrester (BFA) in variations of vacuum chamber pressure and temperature are studied at the transient starting phase. It has been found that applying BFA to decrease the backflow to the vacuum chamber has no significant effect on starting time of the diffuser but it has strong effect on peak pressure and temperature reduction of the vacuum chamber. It is although found that attaining to the steady condition in vacuum chamber is delayed with this instrument. However, using one-way backflow arrester of reasonable size, both the starting time of diffuser and the peak temperature of the vacuum chamber experience a strong reduction. Although, the vacuum chamber steady condition is accelerated with this alternative. Therefore, this device is more suitable than conventional BFA for transient starting phase of the altitude test simulators.

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According to numerous capabilities and increasingly military and commercial applications of radio controlled helicopters, many investigations are being performed on these unmanned aircraft vehicles. Due to nonlinear, complex, unstable and coupled dynamic system and also existing limitations on manual control, the ability of automatic control of these vehicles has gained great importance. In this paper, in addition to investigating different methods of unmanned helicopters dynamic modeling, a multi-level simulator environment has been designed and implemented for flight performance analysis and effects of different parameters have been investigated. The main importance and innovation of present simulator is in possibility of dynamic flight simulation of helicopter using different theories for applications like control system design, performance analysis and real flight simulation. The main difference of the utilized methods is in theories and assumptions applied in main rotor and its flapping dynamics modeling. For each level, Kalman filter and control system design have been performed and preliminary results show the acceptable performance of estimator and controller systems. Considering the complexity of real unmanned helicopter behavior compared to previously performed models, the proposed multi-level simulator can be used as an appropriate tool for the first step before real flight tests.

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In this research experimental results of 60 degree delta wing airplane that conducted in National Low Speed Wind Tunnel is presented. The wind tunnel is closed type has an opened test section that its dimensions are 2.8 m × 2.2 m. Tests Reynolds number is beyond 1.5 million that achievement of this Reynolds number at low speed is unique in the country. Ground effect is measured using a fixed plane that its height is variable. Tests are conducted at the different height and aerodynamics forces and moments are measured using a sting type six component strain gaged balance. The tests results showed that the maximum lift coefficients increased from 1.29 to 1.38 due to presence of the ground plane. The lift coefficient due to ground plane in all range of angle of attack is increased and induced drag coefficient is decreased and consequently, the overall aerodynamics efficiency (lift to drag ratio) is increased from 8 to 14.5. When the distance between model and ground plane is less than half of the wing span, lift curve slope is increased in high rate from 2.66 per radian to 3.11 per radian. Decreasing this distance is caused the aerodynamic center is shifted backward and consequently longitudinal static stability is increased. Consequently presence of ground plane is caused increasing of airplane static stability.

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In this research, the performance study of an altitude test simulator at transient phase of motor burnout is conducted by numerical approach. Using a time dependent pressure profile of a motor in burnout phase, the unsteady exhaust flow is simulated in the main sections of the altitude test simulator, i.e. high expansion ratio nozzle, second throat exhaust diffuser, and vacuum chamber. Present investigation shows that in spite of the high pressure starting condition of the altitude simulator, the supersonic flow in the diffuser tends to breakdown at relatively low combustion pressure in the motor terminating phase. At the breakdown condition, the nozzle exhaust hot gases directed into the vacuum chamber through the annular gap between nozzle and diffuser walls. Present simulation shows that the overall temperature of fluid in vacuum chamber is reached up to 2000 K after the motor burnout. Really, It is potentially dangerous for measurement instruments inside the vacuum chamber. Furthermore; in this research, the influences of backflow arrester (BFA) in variations of vacuum chamber temperature are studied at this transient terminating phase. It has been shown that, the BFA can decrease the exhaust streaming into the chamber in initial breakdown periods. Results show that utilizing a suitable BFA size, the safe temperature condition could be established in vacuum chamber during and after the transient terminating phase of motor.

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Sports simulation mechanisms practically have a lot of appeal and application to implement virtual reality environments. Cycling simulator has a more special place in sports and urban transportation due to the popularity of cycling activities. In this paper, the design and construction of a new motion generating mechanism for an interactive cycling simulator is presented. First, by using the references, the range of velocity and acceleration that the user should experience while cycling has been extracted, and by analyzing other cycling simulators, the required degrees of freedom and its range have been determined. Then, a new motion generating mechanism with two degrees of freedom is designed. Genetic algorithm has been used for dimensional optimization of the mechanism parameters. Kinematics and dynamic equations of the mechanism have been extracted. According to the dynamic model of the mechanism, a controller has been designed using the feedback linearization method and the performance have been investigated. Finally, the designed motion generating mechanism has been constructed and the position control has been implemented on the platform.

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The chewing simulator is designed to perform fatigue tests and durability on a variety of dental specimens. This device, by considering the material (hard or soft) and the type of dental sample (human or animal or artificial) and by applying a specific cyclic and even static force, changes the shape of the sample microscopically and finally this periodic loading and shape change, uses the data to evaluate the fatigue and strength of the sample in the durability test. The testing process of this device will continue until the sample fails or the loading cycle is completed. At design of this device, two movement mechanisms are considered vertically and horizontally, which are responsible for chewing simulation operations, so that in both mechanisms, the movement is reciprocating, the amount and number of this movement is cyclical that is adjustable and controllable, and at the same time, considering the force measuring sensor in this device, the amount of applied force is specified and adjustable at each stage. Two specimens of teeth were placed in the machine for testing. The first priority of testing this device for the samples was their durability under the static force that was applied to the sample step by step. Also, to evaluate the function of the device in the fatigue test, dental specimens were loaded under a certain force and were affected by cyclic motion in both vertical and horizontal directions. According to studies, the refractive force of the specimens varies from 100 N to 800 N, the dental specimens, one artificial and the other natural, failed under the static force, which was in the range of 200 N, that the artificial sample was completely broken, but the natural sample was worn out and part of it was damaged. And this was a good comparison to show the strength and durability of natural teeth compared to artificial ones.