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The purpose of this paper is to explore the effects of wind direction and ease allowance on thermal comfort in sportswear.

The effects of wind direction (front, side, back and calm (no wind) 1.5 m/s) and seven magnitudes of ease allowance on sportswear thermal insulation and surface temperature were investigated. An 11 zones’ thermal manikin was used to acquire the static thermal insulation. Surface temperature was captured by a thermal imager.

The results showed that the wind was a significant effect on thermal performance, however, wind direction effect was only significant in the segment covered with multilayer fabric, such as the abdomen and hip (p=0.034). Although the ease allowance influenced the overall thermal insulation obviously, the difference between seven sizes suits was not significant. Nevertheless, the ease allowance affected the surface temperature of chest and back significantly (p=0.023, 0.007). Correlation between thermal insulation and surface temperature was negative, and correlation level was degraded when affected by wind factor.

Sportswear’s fabric and style did not discussed as effect factors. It would be taken into accounted in the future research.

Wind direction impact thermal comfort in multilayer regions significantly. It is a reference to improve sportswear’s comfort design.

Today, because of the increasing need for the energy resources and the reduction of fossil fuels, renewable energy, especially wind energy, has attracted special attention. The precise forecasting of such energy will be the main factor in designing and investing in this field. On the other hand, the wind energy forecast provides the possibility of optimal use of available resources. In addition, the produce maximum energy would be possible by identifying wind direction and putting wind turbines in the best position.

Time series forecasting methods with long-term memory in this research have been used.

Eventually, the autoregressive fractionally integrated moving average (3,0,0)-FIGARCH (1,0,1) long-term memory model has more acceptable performance. The obtained error is based on the RMSE (0.2889) and the TIC (0.2605) values.

In this paper, the forecast wind direction belongs to Ardebil province and Nayer city in Iran.

The speed and direction of wind are variables that constantly change; hence, it will be difficult to predict the exact wind energy. In recent years, some studies have been conducted on wind speed forecasting, whereas wind direction forecasting has been done in a fewer number of studies. Most studies are related to low-lying areas. As the height of the wind turbine is directly related to the energy generation, 78 m height has been considered in this study.

The purpose of this paper is to understand the natural wind field characteristics of the tunnel entrance section and analyzing the aerodynamic performance of high-speed railway trains (HSRTs) under natural winds.

Three typical tunnel entrance section sites, namely, tunnel–bridge in a dry canyon (TBDC), tunnel–bridge in a river canyon (TBRC) and tunnel–flat ground (TF), are selected to conduct a continuous wind field measurement. Based on the measured wind characteristics, the natural winds of the TBDC and TF sites are reconstituted and imported into the two corresponding full-scale computational fluid dynamics models. The aerodynamic loads of the HSRT running on TBDC and TF with reconstituted winds are simply analyzed.

The von Kármán spectrum can be used to describe the wind field at the tunnel entrance section. In the reconstituted natural wind condition, a time-varying feature of wind speed distribution and leeward side vortex around the HSRT caused by the wind speed fluctuation is found. The fluctuating amplitude of aerodynamic loads at the TBDC infrastructure is up to 97.9% larger than that at the TF infrastructure.

The natural wind characteristics at tunnel entrance sections on the high-speed railway are first measured and analyzed. A numerical reconstitution scheme considering the temporal and spatial variation of natural wind speed is proposed and verified based on field measurement results. The aerodynamic performance of an HSRT under reconstituted natural winds is first investigated.

This paper aims to explore the efficiency of natural ventilation in the bedrooms of typical two-storeyed row houses with newly reconfigured design that incorporate rooftop wind catchers and side windows to create cross ventilation.

A CFD program was used to assess average air velocity coefficient (Cv) in 32 airflow cases. Parameters include location of openings with respect to wind direction, inlet-to-outlet area ratio (IOR) and opening-to-floor area ratio (OFR).

The results reveal that indoor air velocities in the cases of air entering wind catchers are generally higher than those in the cases of air entering side windows while air velocities at the openings are the opposite. The IOR of 1:2 provides best results in terms of both velocities of the indoor air and velocities at the openings. Increasing the OFR from 20% to 50% generally improves indoor air velocities and airflow rates.

This study proved that the new solution of combining one-sided wind catchers and side windows can effectively solve the problem of ventilation uniquely existing in the conditions of typical row houses by catching prevailing wind from two opposite directions into multiple rooms. The results are given as non-dimensional air velocities, which can be interpreted with any climatic data, and therefore can be applied to row houses in any locations and climatic conditions. The findings can create a new and efficient design of row houses that benefits building industry.

THE subject I am to discuss deals with some aspects of aerodrome usability.

The purpose of this paper is to investigate the overall flow and temperature field of the air in the whole power plant, especially around the air‐cooled heat exchanger (ACHE) to evaluate the feasibility of the thermal plant project.

The commercial computational fluid dynamics code FLUENT with standard k‐ε turbulent model was used. The buoyancy of the air was also considered.

It is concluded that plume recirculation occurs in each case due to the wind effect and the suction of the fan. Installing a side board below or above the fan platform (side board I or side board II) is an effective method of avoiding the plume recirculation and, the higher the board, the better the effect. When the height of the side board I H1≥10 m or the height of the side board II H2≥12 m, the temperature distributions of the fan platform will be sufficient to meet the requirement.

A proper distance between the adjacent high buildings and the ACHE should be found with further investigation.

The paper presents a very useful numerical method for the prediction of the flow and temperature field around ACHE or in a large space.

The paper provides the numerical simulation of the flow and heat transfer inside the whole thermal power plant. Suggestions which can effectively avoid the unfavorable influence and ensure the whole system in safe conditions are offered. The study gives some useful information to the design of a thermal power plant with an ACHE system.

In order not to affect the highway and railway traffic under the bridge during the construction process, bridges adopting swivel construction method are increasingly used at areas where the traffic is heavy. Previous studies are mostly conducted by assuming that the bridge is under its own stability conditions, without considering the impact of construction error, changes of external condition and wind-induced vibration on the stability of the bridge, which poses serious challenges to the bridge construction process. This paper aims to analyze the extent to which static load and fluctuating wind effect influence structural stability and to test the credibility of the structure.

A finite element calculation method is used to analyze a T-shaped rigid frame swivel bridge. A full bridge model was built, and a local model of the turntable structure established; the two are then combined means of node coupling. Subsequently, the three sensitivity indexes – deflection rate, stress change rate and the change rate of spherical hinges – are used to evaluate in what way the bridge stability is influenced under various factors.

It is found that the stability of the swivel bridge is quite sensitive to unilateral overweight, steel beam tension and wind-induced vibration effects but less sensitive to the change of bulk density. Also found is that the change of elastic modulus exerts some effects on deflection but has negligible effects on other stability indexes. Furthermore, the transverse unbalanced torque on the bridge generated by wind-induced vibration is an important factor in determining the size of the turntable, indicating that it is not just controlled by the weight of the bridge.

All factors affecting the stability of swivel construction are analyzed, and solutions to reduce the influence are proposed. The influence of wind-induced vibration effects on swivel construction is analyzed for the first time. It is pointed out that wind-induced vibration effects have great influence on the structure, and its influence could not be neglected.

The purpose of this paper is to develop a simplified atmospheric model including constant wind, turbulence, gusts, and wind shear to provide simulation tools for unmanned aerial vehicle (UAV) design, testing, and evaluation within the West Virginia University (WVU) UAV simulation environment.

Analytical methods and experimental data are used to develop the simplified model for air mass motion as a superposition of four major components. Spatial gradients of relative air velocity vector projections are considered for modeling wind shear effects. The total contribution to relative air velocity from the four components in vehicle body axes is used within the WVU UAV simulation environment to calculate aerodynamic forces and moments. The simplified wind model is also interfaced with aircraft sub-system upset conditions models and different autonomous flight scenarios.

The simplified wind model developed provides simulation of different upset environment flight conditions with desirable levels of realism. It allows the testing, comparison, and evaluation of different trajectory tracking solutions for autonomous flight.

The proposed simplified wind model facilitates the investigation of the effects of different atmospheric scenarios on the performance of trajectory generation algorithms and trajectory tracking control laws.

The proposed simplified wind model has been proved to be a high flexibility tool for simulation of UAVs under normal and abnormal flight conditions. It is expected to provide valuable support for the design and analysis of autonomous flight control laws.

This research effort provides a new capability for the advanced simulation of UAV autonomous flight with practically no additional computational cost. It adds an unprecedented level of detail and versatility to the UAV simulation toolkit within a very user-friendly framework aimed at supporting UAV design and analysis for optimal performance and safety under normal and abnormal flight conditions.

Although windy weather conditions have a significant effect on the flight safety and stability of any aircraft, the fact that quadrotors are lighter than other aircraft makes them more sensitive to the wind. This study aims to examine the extent to which quadrotors and their sensors, which are used in many fields and whose use is expected to increase significantly in the future, are affected by wind.

Flight experiments were carried out on different routes assigned by using Pixhawk Holybro 4 and Radiolink flight controllers. In these flight experiments, quadrotors were exposed to winds at different speeds and directions.

In the flight experiments, the deviation amounts in the quadrotor’s route at which wind speed was determined, and it was seen that these deviations were very serious and affected the safe flight at high wind speeds. According to the sensor information obtained from both different quadrotors’ flight experiments at different wind speeds, it was determined that the wind decreased the sensors’ accuracy.

It is foreseen that the data obtained in this study will be a source to be used in the design of quadrotors to be used in public areas in the future and to take the wind into account for safe flight.

In this study, numerous flight tests were carried out experimentally at various speeds from low speeds to high speeds on different routes using different flight controllers. The deviation data on the obtained routes and the effect of the wind on the sensors are experienced in real atmospheric conditions.

The purpose of this paper is to investigate wind power potential of site using wind speed, wind direction and other meteorological data including temperature and air density collected over a period of one year.

The site-specific air density, wind shear, wind power density, annual energy yield and capacity factors have been calculated at 30 and 10 m above the ground level (AGL). The Weibull parameters have been calculated using empirical, maximum likelihood, modified maximum likelihood, energy pattern and graphical methods to determine the other dependent parameters. The accuracies of these methods are determined using correlation coefficient (R²) and root mean square error (RMSE) values.

The site-specific wind shear coefficient was found to be 0.18. The annual mean wind speeds were found to be 5.174 and 4.670 m/s at 30 and 10 m heights, respectively, with corresponding standard deviations of 2.085 and 2.059. The mean wind power densities were found to be 59.50 and 46.75 W/m² at 30 and 10 m heights, respectively. According to the economic assessment, the wind turbine A is capable of producing wind energy at the lowest value of US$ 0.034/kWh.

This assessment provides the sustainable solution of energy which minimizes the dependence on continuous supply of oil and gas to run the conventional power plants that is a major cause of increasing load shedding in the significant industrial and thickly populated city of Pakistan. Also, this will minimize the quarrel between the local power producer and oil and gas supplier during the peak season.

This wind resource assessment has some important social implications including decreasing the environmental issues, enhancing the uninterrupted supply of electricity and decreasing cost of energy per kWh for the masses of Karachi.

The results are showing that the location can be used for installing the wind energy power plant at the lower cost per kWh compared to other energy sources. The wind energy is termed as sustainable solution at the lowest cost.