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At present, the enzyme washing process is widely used in hemp garment in the industry. However, it has many disadvantages. First, it is inefficient and labor-intensive, which can only be produced in small quantities and will take much time for workers to check. Second, its cost is high. The strength loss of the garment is up to 20 percent, with a bad damage. Presently, the enzyme washing process of the gray fabric is not industrialized. The purpose of this paper is to obtain a stable and efficient process for the enzyme washing of the gray fabric.

The whiteness, weight loss rate, strength, dyeing property and fabric style of enzyme washed gray fabrics were studied.

The results showed that the enzyme treated fabric has soft handle, smooth surface, good elasticity and high levelness, as well as low strength reduction rate under the optimized condition of bath ratio of 1:12, cellulase dosage of 0.3 percent, pectinase dosage of 1 g/L, treatment temperature of 55°C, treatment time of 80 min and pH of 6.

First, the process is environment friendly, green and sustainable and, second, it will make the industrialization of the enzyme washing process of gray fabrics, with a high commercial value.

The CL60 steel wheels of metro vehicles running on a specific line need frequent reprofiling due to rapid wear. Considering this problem, a new material for metro wheels was designed. The friction and wear properties of the new material were studied, to reduce the wear rate and extend the service life of metro wheels.

Wheel specimens made of the two steel materials were tested using a GPM-60 wear tester under laboratory conditions. A field test was conducted on a specific metro line to track the wear in wheels made of the new material and CL60 steel wheels.

Under the laboratory conditions, the wear loss in the new material was 24.44% lower than that in CL60 steel. The field test revealed that compared to CL60 steel wheels, the new CL60 steel wheels showed a 19.42% decrease in tread wear on average. The field measurements for the wheels made of the new material are consistent with the results of laboratory simulation, suggesting relatively high wear resistance of the new material.

The results of the study can provide guidance on how to properly select steel material for metro wheels to avoid rapid wear and frequent reprofiling and reduce operating costs.

A new material for metro wheels was designed and developed by optimizing the content of Cr, Si, Mn, V and other elements. This material proved to have better wear resistance in both laboratory and field testing.

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 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.

The purpose of this paper is to explore the issues on how to achieve crowdsourced real-time captioning of sign language by deaf and hard-of-hearing (DHH) people, such that how a system structure should be designed, how a continuous task of sign language captioning should be divided into microtasks and how many DHH people are required to maintain a high-quality real-time captioning.

The authors first propose a system structure, including the new design of worker roles, task division and task assignment. Then, based on an implemented prototype, the authors analyze the necessary setting for achieving a crowdsourced real-time captioning of sign language, test the feasibility of the proposed system and explore its robustness and improvability through four experiments.

The results of Experiment 1 have revealed the optimal method for task division, the necessary minimum number of groups and the necessary minimum number of workers in a group. The results of Experiment 2 have verified the feasibility of the crowdsourced real-time captioning of sign language by DHH people. The results of Experiment 3 and Experiment 4 have shown the robustness and improvability of the captioning system.

Although some crowdsourcing-based systems have been developed for the captioning of voice to text, the authors intend to resolve the issues on the captioning of sign language to text, for which the existing approaches do not work well due to the unique properties of sign language. Moreover, DHH people are generally considered as the ones who receive support from others, but our proposal helps them become the ones who offer support to others.

This paper aims to present a broad review of near-a titanium alloys for high-temperature applications.

Following a brief introduction of titanium (Ti) alloys, this paper considers the near-α group of Ti alloys, which are the most popular high-temperature Ti alloys developed for a high-temperature application, particularly in compressor disc and blades in aero-engines. The paper is relied on literature within the past decade to discuss phase stability and microstructural effect of alloying elements, plastic deformation and reinforcements used in the development of these alloys.

The near-a Ti alloys show high potential for high-temperature applications, and many researchers have explored the incorporation of TiC, TiB SiC, Y₂O₃, La₂O₃ and Al₂O₃ reinforcements for improved mechanical properties. Rolling, extrusion, forging and some severe plastic deformation (SPD) techniques, as well as heat treatment methods, have also been explored extensively. There is, however, a paucity of information on SiC, Y₂O₃ and carbon nanotube reinforcements and their combinations for improved mechanical properties. Information on some SPD techniques such as cyclic extrusion compression, multiaxial compression/forging and repeated corrugation and straightening for this class of alloys is also limited.

This paper provides a topical, technical insight into developments in near-a Ti alloys using literature from within the past decade. It also outlines the future developments of this class of Ti alloys.

This study examines the relationship between streamers' product descriptions, customer comments and online sales and focuses on the moderating effect of streamer–viewer relationship strength.

Between June 2021 and April 2022, the structured data of 965 livestreaming and unstructured text data of 42,956,147 characters from two major live-streaming platforms were collected for the study. Text analysis and regression analysis methods were employed for data analysis.

First, the authors' analysis reveals an inverted U-shaped relationship between comment length and product sales. Notably, comment volume and comment emotion positively influence product sales. Furthermore, the semantic richness, emotion and readability of streamers' product descriptions also positively influence product sales. Secondly, the authors find that the strength of streamer–viewer relationship weakens the positive effects of comment volume and comment emotion without moderating the inverted U-shaped effect of comment length. Lastly, the strength of streamer–viewer relationship also diminishes the positive effects of emotion, semantics and readability of streamers' product descriptions on product sales.

This study is the first to concurrently examine the direct and interactive effects of user-generated content (UGC) and marketer-generated content (MGC) on consumer purchase behaviors in livestreaming e-commerce, offering a novel perspective on individual decision-making and cue utilization in the social retail context.

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.

Legislation plays an essential role in addressing climate change in China. However, many barriers to formulating national legislation to address climate change have so far prevented its enactment. The bottom-up approach adopted in the international climate regime sets a good example. Accordingly, the purpose of this paper is to discuss the regional legislation to address climate change in China through exploring the following two questions: whether it is necessary to enact climate change legislation at regional level first and whether it is feasible to develop such regional legislation in the absence of national climate change law.

This paper analyses the necessity and feasibility of regional legislation to address climate change. Section 2 introduces the current legislative framework on climate change in China. Section 3 investigates whether it is better to push the legislative agenda at regional, rather than national level. Section 4 analyses the feasibility of establishing regional legislative systems. Section 5 explores the key issues in formulating and promoting regional legislation.

This paper concludes that it is necessary and feasible to pilot regional legislation before enacting national legislation. Under these circumstances, local governments can take the initiative to begin formulating regional legislation.

Addressing climate change needs immediate action and effective measures. It is, thus, necessary to reconsider the approach that China should adopt when developing legislation on climate change. This paper contributes to broadening current knowledge of regional climate change legislation in China.