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The purpose of this paper is to improve the comfort and shaping function of seamless shapewear on the material and structure and develop new seamless shapewear products. The shaping figure effect will be verified as well.

The performance of the knitted fabrics made of Polytrimethylene terephthalate (PTT) filament was analyzed by orthogonal experiment and fuzzy mathematical methods analysis, in order to get the optimal conditions for the best performance. The new products were designed and made based on the results of the material research with the consideration of the aesthetic requirements. The shaping effect of seamless shapewears on local and global figure was tested by the methods of the combination of subjective and objective evaluation.

The sample which renders the optimal performance for shapewear is the one with PTT filament as face yarn, nylon core-spun yarn as ground yarn and 3+1 simulate rib knit structure. The material of face yarn, mixed proportion and structure can influence the shape retention, appearance and comfort of PTT fabric in various degrees. Three shapewears which were developed according to the results of material research have different shaping effect. And women with different figures put different satisfaction degrees on each shapewear’s shaping effect.

This paper provides scientific basis and reference for enterprise to design good tight seamless shapewear as well as for consumer to buy suitable products.

In the view of the problems of present shapewears, this paper completed the development of the shapewears and verified the shaping effect of them on women with different figures. The shapewears can be put into production directly.

In order to study whether far-infrared fabrics can be used as a garment for breast cancer patients, or as an adjuvant rehabilitation underwear for breast cancer patients after postoperative radiotherapy and chemotherapy, to eliminate tissue edema. To explore the effect of different far-infrared fabrics on the proliferation and invasion of breast cancer cells as a basic in vitro study.

Six kinds of fabrics of the same specification with different far-infrared nanoparticles were selected. MCF7 and Bcap37 breast cancer cells were used to study the effect of far-infrared fabrics on cell proliferation and invasion. Six kinds of far-infrared fabrics were used to culture breast cancer cells and explore their effects on breast cancer cell growth and the difference between different far-infrared fabrics.

It is found that the far-infrared emissivity of six kinds of fabrics are different, among which tea carbon fabric is the highest, followed by volcanic fabric, graphene fabric and biomass graphene fabric are the lowest. The results show that the far-infrared fabrics can significantly inhibit the proliferation and invasion of breast cancer cells, the higher the far-infrared emissivity is, and the longer the time of far-infrared radiation, the more significant the inhibition effect is.

Far-infrared fabrics can inhibit proliferation and invasion of breast cancer cells in vitro. Therefore, far-infrared fabrics can be used for adjuvant rehabilitation of breast cancer patients. This conclusion provides a basis for the application of far-infrared functional fabrics in the medical field. This conclusion provides a basis for the application of far-infrared functional fabrics in medical field.

People have always been invaded by mosquitoes, and the development of new anti-mosquito fabrics has attracted much attention. The purpose of this paper is to study the effect of knitting process on the performance of anti-mosquito seamless fabrics and provide a basis for obtaining anti-mosquito seamless knitted fabrics with excellent comprehensive performance.

This paper uses bamboo–polyester mosquito repellent yarn containing wormwood extract as the face of seamless knitted fabric. The test factors include ordinary material in the face yarn, ground yarn material, seamless knitted structure and arrangement ratio of ordinary yarn and anti-mosquito yarn in face yarn. According to the quasi-level additional orthogonal test, 12 knitting plans are determined, and the mosquito repellent test and durability test are performed on the fabric.

The experimental results show that the optimal fabric for anti-mosquito performance is 12#, and the average repellent rate after washing 15 times is 58.57%. The corresponding process is that the face yarn is fully anti-mosquito yarn, the fabric is a single-sided mesh structure and the ground yarn is made of 4.4tex moisture-absorbing nylon/2.2tex spandex wrapped yarn.

In this paper, there is still a lack of diversity in the selection of yarn materials and fabrics. In the follow-up research, the authors will use more fabrics and yarn materials for combination and experimentation and simulate and predict the mosquito resistance rate of knitted fabrics with different materials and structures.

The development of anti-mosquito seamless knitted fabrics with good comprehensive performance and the use of environmentally friendly wormwood repellents not only conform to the current people's healthy and environmentally friendly life philosophy, but also promote the development of the functional seamless knitted fabric market.

In addition, seamless knitted fabrics have a huge market prospect, and many of their fabrics are used for sports underwear and outdoor wear. Therefore, the research and development of functional knitted fabrics will attract consumers to buy. While improving the wearing comfort, it can increase profits for the company.

The mosquito-proof functional seamless knitted fabric developed in this research has a high mosquito-proof rate after 15 times and can be used as underwear fabric or outdoor sports fabric.

The purpose of this paper is to clarify the relationship between dynamic clothing pressure of women's sports bras and heart rate variation indexes during playing basketball.

Totally, 35 healthy females aged between 20 and 24 were employed as subjects. Their heart rate variability (HRV) data and the clothing pressure values when wearing sports bras of different bust sizes during playing basketball were measured using Polar RS800CX heart rate monitor and Flexi Force201 thin film type pressure sensor with MFF series pressure test system. Their subjective comfort evaluations were conducted by five-point Likert scale. Grey correlation analysis is used to determine the correlation degree of heart rate variation indexes and subjective comfort evaluations to identify the indexes preferably associated with subjective comfort. Multiple regression analysis is applied to investigate multiple correlations between pressure of test points and the indexes selected above.

Combined subjective comfort evaluation with objective HRV evaluation the heart rate variation indexes preferably associated with subjective comfort of these bras were identified, which includes mHR, mRR, RMSSD, pNN50. By the relationship between dynamic clothing pressure and the indexes above, this study finds that the clothing pressure of the chest area during basketball exercise should be controlled in the range of 2.01-4.74 kPa.

The subjects of different body type should be taken into account. Further, the mathematic models from this study show low R2-value so the models should be provided more reliable prediction.

The present study indicates that there is an inevitable connection between heart rate variation indexes and subjective comfort of basketball sports bras and creatively points out that heart rate variation indexes can partly assess the comfortable clothing pressure. The study can offer theoretical basis for sports apparel industry to develop the comfortable basketball sports bra.

The purpose of this paper is to enhance control accuracy, energy efficiency and productivity of customized industrial robots by the proposed multi-objective trajectory optimization approach. To obtain accurate dynamic matching torques of the robot joints with optimal motion, an improved dynamic model built by a novel parameter identification method has been proposed.

This paper proposes a novel multi-objective optimal approach to minimize the time and energy consumption of robot trajectory. First, the authors develop a reliable dynamic parameters identification method to obtain joint torques for formulating the normalized energy optimization function and dynamic constraints. Then, optimal trajectory variables are solved by converting the objective function into relaxation constraints based on second-order cone programming and Runge–Kutta discrete method to reduce the solving complexity.

Extensive experiments via simulation and in real customized robots are conducted. The results of this paper illustrate that the accuracy of joint torque predicted by the proposed model increases by 28.79% to 79.05% over the simplified models used in existing optimization studies. Meanwhile, under the same solving efficiency, the proposed optimization trajectory consumes a shorter time and less energy compared with the existing optimization ones and the polynomial trajectory.

A novel time-energy consumption optimal trajectory planning method based on dynamic identification is proposed. Most existing optimization methods neglect the effect of dynamic model reliability on energy efficiency optimization. A novel parameter identification approach and a complete dynamic torque model are proposed. Experimental results of dynamic matching torques verify that the control accuracy of optimal robot motion can be significantly improved by the proposed model.

Sensorless passive lead-through programming (LTP) is a promising physical human-robot interaction technology that enables manual trajectory demonstrations based on gravity and friction compensation. The major difficulty lies in static friction compensation during LTP start-up. Instead of static friction compensation, conventional methods only compensate for Coulomb friction after the joint velocity exceeds a threshold. Therefore, conventional start-up external torques must overcome static friction. When the static friction is considerable, it is difficult for conventional LTP to start up and make small movements. This paper aims to decrease the start-up external torque and improve the small movement performance.

This paper reveals a novel usage of a high-gain position-loop in industrial robot applications aimed at sensitively detecting external torque during start-up. Then, the static friction is partly compensated by Coulomb friction to facilitate start-up. In addition, a detailed transition method between the proposed start-up and conventional passive LTP is proposed based on a finite state machine.

Experiments are implemented on the ROKAE XB4 robot to verify the effectiveness of the proposed external torque detection. Compared with the conventional LTP method, the proposed LTP method significantly decreases the start-up external torque and facilitates small movements.

This paper proposes and verifies a novel start-up method of sensorless LTP based on a start-up external torque detection and a transition method between start-up and conventional LTP. This research improves the LTP start-up performance, especially for industrial robots with large static friction.

This study aims to investigate the effect of time-varying passenger flow on the wheel wear of metro vehicles to provide a more accurate model for predicting wheel wear and a new idea for reducing wheel wear.

Sectional passage flow data were collected from an operational metro line. A wheel wear simulation based on time-varying passenger flow was performed via the SIMPACK software to obtain the worn wheel profile and wear distribution. The simulation involves the following models: vehicle system dynamics model, wheel-track rolling contact model, wheel wear model and variable load application model. Later, the simulation results were compared with those obtained under the traditional constant load condition and the measured wear data.

For different distances traveled by the metro vehicle, the simulated wheel profile and wear distribution under the variable load remained closer to the measurements than those obtained under the constant load. As the distance traveled increased, the depth and position of maximum wear and wear growth rate under the variable load tended to approach the corresponding measured values. In contrast, the simulation results under the constant load differed greatly from the measured values. This suggests that the model accuracy under the variable load was significantly improved and the simulation results can offer a more accurate basis for wear prediction.

These results will help to predict wheel wear more accurately and provide a new idea for simulating wheel wear of metro vehicles. At the same time, measures for reducing wheel wear were discussed from the perspective of passenger flow changes.

Existing research on the wheel wear of metro vehicles is mainly based on the constant load condition, which is quite different from the variable load condition where the passenger flow in real vehicles varies over time. A method of simulating wheel wear based on time-varying load is proposed in this paper. The proposed method shows a great improvement in simulation accuracy compared to traditional methods and can provide a more accurate basis for wear prediction and wheel repair.

Considering that a meet between high-speed trains can generate aerodynamic loads, this study aims to investigate the effect of high-speed train meet on wheel wear at different speeds to provide a more accurate wheel wear model and a new idea for reducing wheel wear.

The train speed was set at 250, 300, 350 and 400 km/h separately, and a vehicle system dynamics model was constructed using the parameters of an actual high-speed train on a line. The aerodynamic forces arising from constant-speed train meet were then applied as additional excitation. Semi-Hertzian theory and Kalker’s simplified theory were used to solve the wheel/rail contact problems. The wheel wear was calculated using Archard wear model. The effect of train meet on wheel wear was analyzed for the whole train, different cars and different axles.

According to the results, all wheels show a wear increase in the case of one train meet, compared to the case of no train meet. At 250, 300, 350 and 400 km/h, the total wheel wear increases by 4.45%, 4.91%, 7.57% and 5.71%, respectively, over the entire operational period. The change in speed has a greater impact on wheel wear increase in the head and tail cars than in the middle car. Moreover, the average wear increase in front-axle wheels is 1.04–2.09 times that in rear-axle wheels on the same bogie.

The results will help to analyze wheel wear more accurately and provide theoretical guidance for wheel repair and maintenance from the perspective of high-speed train meet.

At present, there is a lot of focus on the impact of high-speed train meet on the dynamic performance of vehicles. However, little research is available on the influence of train meet on wheel wear. In this study, a vehicle dynamics model was constructed and the aerodynamic forces generated during high-speed train meet were applied as additional excitation. The effect of train meet on wheel wear was analyzed for the whole train, different cars and different axles. The proposed method can provide a more accurate basis for wear prediction and wheel repair.

The purpose of this paper is to study the wear evolution of metro wheels under the conditions of different track sequences, track composition and vehicle load and then to predict wheel wear and to guide its maintenance.

By using the SIMPACK and MATLAB software, numerical simulation analysis of metro wheel wear is carried out based on Hertz theory, the FASTSIM algorithm and the Archard model. First of all, the vehicle dynamics model is established to calculate the motion relationship and external forces of wheel-rail in the SIMPACK software. Then, the normal force of wheel-rail is solved based on Hertz theory, and the tangential force of wheel-rail is calculated based on the FASTSIM algorithm through the MATLAB software. Next, in the MATLAB software, the wheel wear is calculated based on the Archard model, and a new wheel profile is obtained. Finally, the new wheel profile is re-input into the vehicle system dynamics model in the SIMPACK software to carry out cyclic calculation of wear.

The results show that the setting order of different curves has an obvious influence on wear when the proportion of the straight track and the curve is fixed. With the increase in running mileage, the severe wear zone is shifted from tread to flange root under the condition of the sequence-type track, but the wheel wear distribution is basically stable for the unit-type track, and their wear growth rates become closer. In the tracks with different straight-curved ratio, the more proportion the curved tracks occupy, the closer the severe wear zone is shifted to flange root. At the same time, an increase in weight of the vehicle load will aggravate the wheel wear, but it will not change the distribution of wheel wear. Compared with the measured data of one city B type metro in China, the numerical simulation results of wheel wear are nearly the same with the measured data.

These results will be helpful for metro tracks planning and can predict the trend of wheel wear, which has significant importance for the vehicle to do the repair operation. At the same time, the security risks of the vehicle are decreased economically and effectively.

At present, many scholars have studied the influence of metro tracks on wheel wear, but mainly focused on a straight line or a certain radius curve and neglected the influence of track sequence and track composition. This study is the first to examine the influence of track sequence on metro wheel wear by comparing the sequence-type track and unit-type track. The results show that the track sequence has a great influence on the wear distribution. At the same time, the influence of track composition on wheel wear is studied by comparing different straight-curve ratio tracks; therefore, wheel wear can be predicted integrally under different track conditions.

Metro wheels running on different lines can undergo wear at different positions. This paper aims to investigate the effects of wheel wear at two typical positions, i.e. wheel flange and tread, on the dynamic performance of metro vehicles and analyzes the differences, with an aim of providing theoretical support on wheel reprofiling for different metro lines.

Wheel profile data were measured on two actual metro lines, denoted A and B. It was observed that wheel wear on Lines A and B was concentrated on flanges and treads, respectively. A metro vehicle dynamics model was built using multibody dynamics software SIMPACK. Then it was applied to analyze the differences in effects of wheel wear at different positions on vehicle dynamic performance (VDP) for various speeds (50, 60 and 70 km/h) and line conditions (straight line, R1000m, R600m and R300m curves). Critical speed and vibration acceleration were used as indicators of VDP during linear motion (on straight track), while VDP during curvilinear motion (on curved track) was evaluated in terms of wheel/rail lateral force, wheel/rail vertical force, derailment coefficient and wheel unloading rate.

First, compared to wheel profile with tread wear, wheel profile with flange wear showed better performance during linear motion. When the distance traveled reached 8 × 104 and 14 × 104 km, the vehicle’s critical speed was 12.2 and 21.6% higher, respectively. The corresponding vertical and lateral vibration accelerations were 59.7 and 74.8% lower. Second, compared to wheel profile with flange wear, that with tread wear showed better performance during curvilinear motion, with smaller wheel/rail lateral force, derailment coefficient and wheel unloading rate. When the vehicle speed was 50, 60 and 70 km/h, the maximum difference in the three indicators between the two wheel profiles was 40.2, 44.7 and 23.1%, respectively. For R1000m, R600m and R300m curves, the corresponding maximum difference was 45.7, 69.0 and 44.4%, respectively.

The results of the study can provide a guidance and theoretical support on wheel reprofiling for different metro lines. On lines with large proportions of curved sections, metro vehicles are more prone to wheel flange wear and have poorer dynamic performance during curvilinear motion. Therefore, more attention should be paid to flange lubrication and maintenance for such lines. On lines with higher proportions of straight sections, metro vehicles are more prone to tread wear and have poorer performance on straight sections. So, tread maintenance and service requires more attention for such lines.

Existing research has focused primarily on the effects of wheel wear on VDP, but fails to consider the differences in the effects of wheel wear at different positions on VDP. In actual metro operation, the position of wheel wear can vary significantly between lines. Based on measured positions of wheel wear, this paper examines the differences in the effects of wheel wear at two typical positions, i.e. tread and flange, on VDP in detail.