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The purpose of this paper is to predict the effect of bra pad specifications on breast deformation during jumping using a finite element (FE) method. Breast deformation is a key concern for women during exercise and can be effectively controlled with sports bras. In most studies, the deformation of breasts when wearing a sports bra is measured using motion capture devices to judge their effectiveness. However, the operation of such devices is highly complex and time-consuming. Computer-aided technology is an efficient way to simulate these experiments.

In this study, the breast model was obtained using three-dimensional (3D) scanning. Assembling models were obtained for FE analysis using reverse engineering and computer-aided design (CAD) software. The breast deformation results were obtained by completing pre-processing, solving and post-processing in the FE simulation software. To extend the application of these models, pads of different sizes and thicknesses within the bra were constructed to simulate the effect of pads on breast deformation.

The calculated root mean square errors were <1%, which indicated good agreement between the FE and experimental data in all the models. Nipple deformation was always the largest in most models. The smallest deformation occurred at the superior position of breasts in all models. In addition, larger pads were not effective in reducing breast deformation; however, thicker pads were.

The method developed in this study provides an effective way to predict breast deformation in multiple positions and is convenient for designing compression bras.

An improved waterproof seam production technology (ultrasonic welding-thermo adhesive tape sealing (USW-TATS)) was developed in this study. The technology will improve the waterproof performance of seam which has problem resulted from needle holes and thread like seam leaking and excess shrinkage.

Threadless seams were produced by ultrasonic welding (USW) with coated and lamination fabric to replace the traditional sewing process in Sewing-thermo adhesive tape sealing (S-TATS). The process efficiency was evaluated by Methods-Time Measurement (MTM). Seam performance including hydrostatic pressure, shrinkage and tear force was compared among three technologies (USW, USW-TATS and S-TATS). The effect of ultrasonic welding parameters (amplitude, roller pressure and roller speed) on the USW-TATS seam performance was investigated.SEM analysis was carried out to examine the condition and morphology of the joints cross section.

It was found that waterproof performance and dimensional stability of USW-TATS seam were superior to that of S-TATS seam. Tear force and hydrostatic pressure increased firstly and then decreased with the increasing of USW parameters in UAW-TATS process. Binary regression relationships were found between the USW parameters and tear force or hydrostatic pressure. Shrinkage decreased with the increasing of roller pressure and speed.

Research results can be applied to predict seam performance of waterproof clothing, reduce equipment parameters setting time and enhance product quality in industry.

A threadless production technology (USW-TATS) was proposed to improve waterproof performance and dimensional stability of outdoor clothing seams.

The purpose of this paper is to explore a novel breast volume measuring method by mesh projection based on three-dimensional (3D) point cloud data.

Mesh projection method, a rapid and accurate method to calculate the volume of models described by triangular meshes, was transplanted to calculate breast volume based on 3D point cloud data derived from a [TC]2 3D scanner. A simple landmarking procedure was developed to decide breast boundary. Breast volumes derived from mesh projection method were compared to the results of water displacement by statistical analysis to validate its accuracy.

A novel breast volume measurement method is developed based on mesh projection method. By comparison of water displacement, mesh projection method is proved to be accurate to calculate breast volume. Furthermore, a simple and standard breast boundary landmarking procedure is established, which avoids the arbitrariness of the definition of breast boundary and improves the repetition of landmarking.

A simple and convenient tool is provided for bra industries to rapidly and accurately measure breast volume.

Mesh projection method is primarily applied to determine breast volume based on 3D point cloud data. Meanwhile, a simple and standard breast boundary landmarking procedure is put forward.

Limited by the types of sensors, the state information available for musculoskeletal robots with highly redundant, nonlinear muscles is often incomplete, which makes the control face a bottleneck problem. The aim of this paper is to design a method to improve the motion performance of musculoskeletal robots in partially observable scenarios, and to leverage the ontology knowledge to enhance the algorithm’s adaptability to musculoskeletal robots that have undergone changes.

A memory and attention-based reinforcement learning method is proposed for musculoskeletal robots with prior knowledge of muscle synergies. First, to deal with partially observed states available to musculoskeletal robots, a memory and attention-based network architecture is proposed for inferring more sufficient and intrinsic states. Second, inspired by muscle synergy hypothesis in neuroscience, prior knowledge of a musculoskeletal robot’s muscle synergies is embedded in network structure and reward shaping.

Based on systematic validation, it is found that the proposed method demonstrates superiority over the traditional twin delayed deep deterministic policy gradients (TD3) algorithm. A musculoskeletal robot with highly redundant, nonlinear muscles is adopted to implement goal-directed tasks. In the case of 21-dimensional states, the learning efficiency and accuracy are significantly improved compared with the traditional TD3 algorithm; in the case of 13-dimensional states without velocities and information from the end effector, the traditional TD3 is unable to complete the reaching tasks, while the proposed method breaks through this bottleneck problem.

In this paper, a novel memory and attention-based reinforcement learning method with prior knowledge of muscle synergies is proposed for musculoskeletal robots to deal with partially observable scenarios. Compared with the existing methods, the proposed method effectively improves the performance. Furthermore, this paper promotes the fusion of neuroscience and robotics.

In order to encourage the high-water-consumption (HWC) manufacturers to carry out water-saving transformation relying on self-strength or outsourcing to a water-saving service company (WSSC) during production processes, government subsidies are provided according to water-saving efforts (WSE) or investment cost. In this context, the authors derive the participant's equilibrium decisions and the manufacturer's water-saving strategy. Additionally, the effects of subsidies on WSE and stakeholders' profits are discussed.

Mathematical models including optimization model and Stackelberg game model are constructed under different subsidy schemes.

The study finds that (1) there exists a threshold related to the subsidy coefficient for the HWC manufacturer when choosing between self-saving and outsourcing-saving. (2) When the technological competitive advantage between WSSC and manufacturer is within a certain range, government's subsidy promotes HWC enterprises to choose outsourcing-saving. (3) Given a water-saving mode, subsidy on investment cost is more effective for the government to achieve more environmental performance.

First, subsidy endogeneity can be considered to explore the optimal interval for government subsidies to maximize social welfare. Second, in outsourcing-saving, other types of contract can be discussed. Another extension is about model uncertainties. Finally, other policies on improving water efficiency can be also examined.

The paper includes implication for HWC manufacturers to select the best water-saving mode under subsidy, and it allows policymakers to understand the efficiency of proposed subsidies.

Decisions on water-saving efforts, selection of water-saving modes and operational planning are also regarded as business strategies in the paper. Particularly, the influences of different government subsidies are also considered and compared.

The purpose of this study is to explore the relationship between ambidextrous leadership and sustainability performance. In addition, this study also discusses how ambidextrous leadership affects sustainability performance through employees' green creativity and green product innovation.

This study obtained research data from a questionnaire survey of 307 manufacturing enterprise leaders in China and used regression and bootstrap analysis to test the research hypotheses.

(1) Ambidextrous leadership positively influences sustainability performance. (2) Employees' green creativity mediates the relationship between ambidextrous leadership and sustainability performance. (3) Green product innovation also mediates the relationship between ambidextrous leadership and sustainability performance. (4) The intermediary chain constructed by employees' green creativity and green product innovation has serial mediation effects on the relationship between ambidextrous leadership and sustainability performance.

This study contributes to the literature on leadership and corporate sustainability by clarifying the relationship between ambidextrous leadership and sustainability performance. Meanwhile, this study reveals the influence mechanism of ambidextrous leadership on sustainability performance by analyzing the serial mediation effects of employees' green creativity and green product innovation.

Through the scientific and reasonable evaluation of the site selection of the emergency material reserve, the optimal site selection scheme is found, which provides reference for the future emergency decision-making research.

In this paper, we have chosen three primary indicators and twelve secondary indicators to construct an assessment framework for the determination of suitable locations for storing emergency material reserves. By mean of the improved entropy weight-order relationship weight determination method, the evaluation model of kullback leibler-technique for order preference by similarity to an ideal solution (KL-TOPSIS) emergency material reserve location based on relative entropy is established. On this basis, 10 regional storage sites in Beijing are selected for evaluation.

The results show that the evaluation model of the location of emergency material reserve not only respects the objective knowledge, but also considers the subjective information of the experts, which makes the ranking result of the location of the emergency material reserve more accurate and reliable.

Firstly, the modification factor is added to the calculation formula of traditional entropy weight method to complete the improvement of entropy weight method. Secondly, the order relation analysis method is used to assign subjective weights to the indicators. The principle of minimum information entropy is introduced to determine the comprehensive weight of the index. Finally, KL distance and TOPSIS method are combined to determine the relative entropy and proximity degree of alternative solutions and positive and negative ideal solutions, and the scientific and effective of the method is proved by case study.

The purpose of this paper is to focus on an optimizing maintenance policy with repair limit time for a new type of aircraft component, in which the lifetime is assumed to be an uncertain variable due to no historical operation data, and the repair time is a random variable that can be described by the experimental data.

To describe this repair limit time policy over an infinite time horizon, an extended uncertain random renewal reward theorem is firstly proposed based on chance theory, involves uncertain random interarrival times and stochastic rewards. Accordingly, the uncertain random programming model, which minimized the expected maintenance cost rate, is formulated to find the optimal repair limit time.

A numerical example with sensitivity analysis is provided to illustrate the utility of the proposed policy. It provides a useful reference and guidance for aircraft optimization. For maintainers, it plays an important guiding role in engineering practice.

The proposed uncertain random renewal reward process proved useful for the optimization of maintenance strategy with maintenance limited time for a new type of aircraft components, which provides scientific support for aircraft maintenance decision-making for civil aviation enterprises.

This paper aims to evaluate the inhibition efficiency of thiadiazole derivatives, such as 2,5-dimercapto-1,3,4-thiadiazole (DMTD), 5-methly-2-mercapto-1,3,4-thiadiazole (MMTD) and 2,5-dithiododecyl-1,3,4-thiadiazole (DDTD), in 50 mg/L hydrogen sulfide for silver strip.

Evaluation was carried out by corrosion-inhibiting test, electrochemical measurement and surface analysis techniques. 3D surface profiler, atom force microscopy, scanning electron microscopy and energy-dispersive X-ray analysis were applied and finally confirmed the existence of the adsorbed film.

The electrochemical measurement showed that the inhibition efficiency increases with increasing inhibitor concentration in 50 mg/L hydrogen sulfide solution, while the corrosion rate and the corrosion current decrease. Weight-gained measurements also indicated that inhibitor decreases the corrosion rate in the studied solution. The adsorption of DMTD and MMTD on the silver surface obeys Temkin’s adsorption isotherm, but the adsorption of DDTD follows Langmuir’s adsorption isotherm. That means that the inhibition mechanism is different between DMTD, MMTD and DDTD. The ΔG0_ad values of DMTD, MMTD and DDTD were −37.47, −37.29 and −38.69 kJ/mol, respectively. It showed that there was an adsorption bond between silver surface and inhibitor, and the adsorption belongs to chemical adsorption.

The inhibitors have an excellent inhibition efficiency, and the best inhibition efficiency is 91.76 per cent. Inhibitors can effectively inhibit metal corrosion in the oil and gas.