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Fast obstacle avoidance path planning is a challenging task for multijoint robots navigating through cluttered workspaces. This paper aims to address this issue by proposing an improved path-planning method based on the distorted space (DS) method, specifically designed for high-dimensional complex environments.

The proposed method, termed topology-preserved distorted space (TP-DS) method, mitigates the limitations of the original DS method by preserving space topology through elastic deformation. By applying distinct spring constants, the TP-DS autonomously shrinks obstacles to microscopic areas within the configuration space, maintaining consistent topology. This enhancement extends the application scope of the DS method to handle complex environments effectively.

Comparative analysis demonstrates that the proposed TP-DS method outperforms traditional methods regarding planning efficiency. Successful obstacle avoidance tasks in the cluttered workspace validate its applicability on a physical 6-DOF manipulator, highlighting its potential for industrial implementations.

The novel TP-DS method generates a topology-preserved collision-free space by leveraging elastic deformation and shows significant capability and efficiency in planning obstacle-avoidance paths in complex application scenarios.

Unsupervised domain adaptation object detection not only mitigates model terrible performance resulting from domain gap, but also has the ability to apply knowledge trained on a definite domain to a distinct domain. However, aligning the whole feature may confuse the object and background information, making it challenging to extract discriminative features. This paper aims to propose an improved approach which is called intrinsic feature extraction domain adaptation (IFEDA) to extract discriminative features effectively.

IFEDA consists of the intrinsic feature extraction (IFE) module and object consistency constraint (OCC). The IFE module, designed on the instance level, mainly solves the issue of the difficult extraction of discriminative object features. Specifically, the discriminative region of the objects can be paid more attention to. Meanwhile, the OCC is deployed to determine whether category prediction in the target domain brings into correspondence with it in the source domain.

Experimental results demonstrate the validity of our approach and achieve good outcomes on challenging data sets.

Limitations to this research are that only one target domain is applied, and it may change the ability of model generalization when the problem of insufficient data sets or unseen domain appeared.

This paper solves the issue of critical information defects by tackling the difficulty of extracting discriminative features. And the categories in both domains are compelled to be consistent for better object detection.

Proper platform pose is important for the mobile manipulator to accomplish dexterous manipulation tasks efficiently and safely, and the evaluation criterion to qualify manipulation performance is critical to support the pose decision process. This paper aims to present a comprehensive index to evaluate the manipulator’s operation performance from various aspects.

In this research, a criterion called hybrid manipulability (HM) is proposed to assess the performance of the manipulator’s operation, considering crucial factors such as joint limits, obstacle avoidance and stability. The determination of the optimal platform pose is achieved by selecting the pose that maximizes the HM within the feasible inverse reachability map associated with the target object.

A self-built mobile manipulator is adopted as the experimental platform, and the feasibility of the proposed method is experimentally verified in the context of object-grasping tasks both in simulation and practice.

The proposed HM extends upon the conventional notion of manipulability by incorporating additional factors, including the manipulator’s joint limits, the obstacle avoidance situation during the operation and the manipulation stability when grasping the target object. The manipulator can achieve enhanced stability during grasping when positioned in the pose determined by the HM.

The purpose of this paper is to clarify how the micro-structure and -properties of wool fibers influence the pilling property of woolen fabrics.

The fuzzing and pilling property of woolen fabrics was investigated, based on micro-scale including basic structural characteristics of wool fibers, wool scale topography and surface friction, etc. Scanning electron microscope was used to analyze wool fiber structure; frictional coefficients were measured by capstan method. Then three different kinds of wool fibers are spun into yarns, then knitted into woolen fabrics, whose pilling grade were estimated by means of Pillbox method.

Results show that the finer the fiber, the fabric pilling degree will be higher; the shorter the fiber, the fabric’s pilling is more serious; the number of pilling is decreasing with the increasing number of crimp; the longer the scales, the better anti-pilling property of fabrics, while the larger the scale thickness, the worse the anti-pilling property; and initially, with the increasing DFEs, fabrics are not easy to pilling, however, there exists a critical value.

Fuzzing and pilling property of woolen fabrics are affected by number of factors, including raw fibers, yarns, fabric tissue and finishing process, etc. In this paper, the authors exclude the influence of yarns’ parameter and fabrics’ tissue, etc., but focus on the micro-structure and -properties of raw wool fibers; and establish a direct connection between fabrics’ pilling property and fibers’ parameters.

This study aims to systematically investigate the tribological behaviors of metal and polyethylene using lubricants composed of four synovial fluid (SF) components. In addition, the changes in protein conformation during wear were analyzed to establish the correlation between protein conformation and tribological properties.

A pin-on-disk tester with multidirectional sliding motion was used for tribological properties observation between metal and polyethylene pairs. Simulated SFs with four main constituents were used as the testing lubricants. Differential scanning calorimetry and Raman were used to characterize the changes in protein conformation during wear.

The coupling of lipids and hyaluronic acid further suppressed protein denaturation. The protein structures of the adsorption film and the ensnared protein chains in the friction zone were maintained to a certain extent, thus improving the friction and wear of polyethylene.

These findings established the correlation between protein conformation and friction and wear, promoting the understanding of the lubrication mechanism of artificial joints.

This paper aims to investigate the tribology, corrosion resistance and biocompatibility of high-temperature gas-nitrided Ti6Al4V alloy.

The tribological properties were studied by reciprocating wear tester. The corrosion resistance was evaluated by using potentiodynamic polarization test. The purified mouse leukaemic monocyte macrophage cells are used to investigate the biocompatibility.

The results show that the nitriding treatment leads to a significant improvement in the hardness and tribological properties of Ti6Al4V alloy. Specifically, compared to untreated Ti6Al4V, the hardness increases from 3.24 to 9.02 GPa, while the wear rate reduces by 12.5 times in sliding against a Ti6Al4V cylinder and 19.6 times in sliding against a Si3N4 ball. Furthermore, the nitriding treatment yields an improved corrosion resistance and a biocompatibility similar to that of untreated Ti6Al4V.

The nitrided Ti6Al4V alloy is an ideal material for the fabrication of load-bearing artificial implants.

This paper is a study of the current trends and conditions of electronic resources for Chinese studies, based on a recent survey on the Internet of 29 Chinese libraries in North America and eight Chinese libraries in China, Taiwan and Hong Kong. The survey discussed current electronic resources for Chinese studies, with a union list of major Chinese language databases currently used in libraries in Asia and the US. Current views on the use and development of electronic resources for Chinese studies were summarised.

By investigating the thermal-mechanical interaction between the through silicon via (TSV) and the Cu pad, this study aimed to determine the effect of electroplating defects on the upper surface protrusion and internal stress distribution of the TSV at various temperatures and to provide guidelines for the positioning of TSVs and the optimization of the electroplating process.

A simplified model that consisted of a TSV (100 µm in diameter and 300 µm in height), a covering Cu pad (2 µm thick) and an internal drop-like electroplating defect (which had various dimensions and locations) was developed. The surface overall deformation and stress distribution of these models under various thermal conditions were analyzed and compared.

The Cu pad could barely suppress the upper surface protrusion of the TSV if the temperature was below 250 ?. Interfacial delamination started at the collar of the TSV at about 250 ? and became increasingly pronounced at higher temperatures. The electroplating defect constantly experienced the highest level of strain and stress during the temperature increase, despite its geometry or location. But as its radius expanded or its distance to the upper surface increased, the overall deformation of the upper surface and the stress concentration at the collar of the TSV showed a downward trend.

Previous studies have not examined the influence of the electroplating void on the thermal behavior of the TSV. However, with the proposed methodology, the strain and stress distribution of the TSV under different conditions in terms of temperature, dimension and location of the electroplating void were thoroughly investigated, which might be beneficial to the positioning of TSVs and the optimization of the electroplating process.

Much prior literature has discussed bioethics from a Confucian perspective in biomedical research, but little has applied Confucianism in examining ethics in social and behavioral research involving human subjects. This paper aims to reexamine the Belmont principles in social and behavioral research from a Confucian perspective to discuss their applicability and limitations and propose implications for revising or extending them potentially in the future.

A comparison is conducted on bioethics and social and behavioral research ethics. Afterward, a critical analysis is conducted on the Belmont principles of respect for persons, beneficence and justice from a Confucian perspective regarding their application in social and behavioral research.

From a Confucian perspective, the Belmont principles are necessary but may not be sufficient to cover the width and depth of ethical issues in social and behavioral research, such as those in crowd work-based research. This paper proposes that ethical guidelines for social and behavioral research may need to be updated from the Belmont principles adopting or incorporating certain Confucian ethics.

Social and behavioral research ethics have been relatively marginal compared to the bioethics deliberation in the existing literature. Unlike Beauchamp and Childress’s continued efforts in refining ethical guidelines for biomedical research specifically, little similar work has been done in this area since the Belmont report’s publication in 1979. This paper sheds light on building more refined and specific ethical guidelines to navigate the ever-growing numbers and diversities of nonmedical research topics, methodologies and contexts.

Helical coil electromagnetic launchers (HEMLs) using motion-induced commutation strategy solve the problem of synchronization control perfectly. HEMLs can meet the requirements of multiple applications such as the electromagnetic catapult, electromagnetic mortar and high-velocity coilgun. The trade-off between the velocity and efficiency is an important basis for these different applications. To optimize such objectives before actual design, the purpose of this paper is to focus on the efficient and flexible calculation model and algorithm. A novel structure of HEML is proposed after the transient simulation by this algorithm, which can improve the energy conversion efficiency and suppress the muzzle arc without affecting the velocity too much.

The equivalent circuit model of the launcher is established and the governing equations are derived. A combination of the four-stage Runge–Kutta method and the trapezoidal quadrature formula are used to solve the governing equations.

With smaller number of turns in the coils of HEML, the velocity is larger and the efficiency is lower. The non-uniform HEML is an effective option to improve the energy conversion efficiency and to suppress the muzzle arc with almost the same muzzle velocity as the conventional HEML.

The paper presents a common model and a flexible fast numerical method which can be used in multi-objective optimization of HEMLs such as the genetic algorithm. A new structure of the non-uniform HEML is proposed to improve the energy conversion efficiency and to suppress the muzzle arc of the launcher.