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This paper examines the perceptual antecedents of the appeal of online computer games from the users’ perspective. It proposes a framework that links the perceived ease of use, perceived entertainment, and perceived irritation with the appeal of an online computer game, measured through attitude toward the game and the user’s intention to play again. Results from a field study indicate that the three proposed perceptual antecedents explain over 60 per cent of variance in both attitude and intention to return. This research demonstrates that factors contributing to user perceptions of online games are important aspects of computer game development. Further research through experimental studies is also advocated.

The purpose of this paper is to evaluate the effect of different amounts of sodium hydroxide (NaOH) introduced during the resin synthesis on the properties of bark‐phenol‐formaldehyde (BPF) adhesives aims at achieving a balance between storage life and other properties of BPF adhesives.

Based on the best synthetic technologies for the production of BPF adhesives obtained in a previous study, a new synthetic technology is developed for the production of BPF adhesives that involve a three‐step addition of NaOH using different amounts of NaOH in the third charge. Gel permeation chromatography is used to evaluate properties of the phenol‐formaldehyde (PF) and BPF adhesives.

The amount of NaOH in the third charge has an important influence on many BPF adhesive properties. The paper determines that the synthetic technology involving three‐step NaOH additions with only water introduced in the third charge of NaOH produces a BPF adhesive with the longest storage life and best bonding strength.

BPF adhesives are very complex systems with many unknown variables.

The improved storage life of the BPF adhesive prepared with the new synthetic technology is comparable to that of a commercial PF adhesive, which indicates that this new technology shows greater potential for commercial applications.

A new synthetic technology is developed to produce a BPF adhesive that is more comparable to commercial PF adhesives than other BPF adhesives in terms of storage life and other resin properties.

This paper aims to study the turning strategies for the bounding quadruped robot with an active spine and explore the significant role of the spine in the turning locomotion.

Firstly, the bounding gait combining the pitch motion of the spine with the leg motion is presented. In this gait, the spine moves in phase with the front legs. All the joints of the legs and spine are controlled by cosine signals to simplify the control, and the initial position and oscillation amplitude of the joints can be tuned. To verify the effectiveness of the proposed gait, the spine joints are set with different initial positions and oscillation amplitudes, and the initial position and oscillation amplitude of the leg joints are tuned to make the virtual model do the best locomotion in terms of the speed and stability in the simulation. The control signals are also used to control a real robot called Transleg. Then, three different turning strategies are proposed, including driving the left and right legs with different strides, swaying the spine in the yaw direction and combining the above two methods. Finally, these strategies are tested on the real robot.

The stable bounding locomotion can be achieved using the proposed gait. With the spine motion, the speed of the bounding locomotion is increased; the turning radius is reduced; and the angular velocity is increased.

A simple and flexible planning of the bounding gait and three turning strategies for the bounding quadruped robot are proposed. The effectiveness of the proposed bounding gait, along with the beneficial effect of the spine motion in the yaw direction on the turning locomotion is demonstrated with the computer simulations and robot experiments. This will be instructive for the designing and actuating of the other quadruped robots.

This paper explores the nexus between lean operations, eco-product innovativeness, social performance, green performance and business performance. Both direct and indirect effects are tested among the variables under consideration in this study.

Data is garnered from 166 Ghanaian small and medium-sized enterprise (SME) manufacturers. All hypothesized relationships are tested using partial least square-structural equation modeling.

The results suggest that lean operations has a significant positive effect on eco-product innovativeness, social performance, green performance and business performance. The results further indicate that eco-product innovativeness significantly influences green performance and social performance, but does not significantly influence business performance. The mediation procedure performed shows that eco-product innovativeness plays a complementary partial mediation role between lean operations, social performance, green performance and business performance.

The study provides enough evidence that informs managers that the application of lean operations should be a necessity instead of an afterthought when pursuing their sustainable performance targets. The study specifically enlightens Ghanaian managers and those in similar environs to substantially invest in lean operations to achieve eco-product innovativeness and contribute to the survival of the manufacturing sector.

In addition to expanding lean operations and environmental management literature, the study happens to be among the scant studies that has verified the direct and indirect effects between lean operations, eco-product innovativeness, social, green and business performances.

The purpose of this paper is to present a priority evaluation method for data module (DM) modification tasks based on the thoughts of real-time systems. Tasks in practical cases can be sorted by this method after analyzing their time records. Civil aircraft technical publications (CATPs) are the key technical guarantee for aircraft companies to efficiently operate and service aircraft. Orienting the maintenance business of CATPs, this method regards DM as the research object to help DM editors efficiently finish their time-consuming work.

This method provides a priority order of modification tasks for DM editors by calculating two indicators: priority value (PV) and priority level (PL). Table of task priority must be first designed for certain evaluation work followed by generating PLs and PVs of modification tasks. Then editors can fully understand the urgency of these tasks using the rank orders of these two indicators.

This method can be applied into a software system used by CATPs department of aircraft manufacturers. According to the engineers’ opinions from a manufacturer in China, it is convenient for the practical application.

Availability and rationality are verified by the practical case and a software system. In addition, the originality characterized by a thinking for engineers to quantify the evaluation work of DM modification task priority, and they could also customize this method by taking modification difficulty and other factors into account.

The properties of materials under impact load are introduced in terms of metal, nonmetallic materials and composite materials. And the application of impact load research in biological fields is also mentioned. The current hot research topics and achievements in this field are summarized. In addition, some problems in theoretical modeling and testing of the mechanical properties of materials are discussed.

The situation of materials under impact load is of great significance to show the mechanical performance. The performance of various materials under impact load is different, and there are many research methods. It is affected by some kinds of factors, such as the temperature, the gap and the speed of load.

The research on mechanical properties of materials under impact load has the characteristics as fellow. It is difficult to build the theoretical model, verify by experiment and analyze the data accumulation.

This review provides a reference for further study of material properties.

This paper aims to purpose an improved sensorless position-based force controller in gravitational direction for applications including polishing, milling and deburring.

The first issue is the external force/torque estimation at end-effector. By using motor’s current information and Moore-Penrose generalized inverse matrix, it can be derived from the external torques of every joints for nonsingular cases. The second issue is the force control strategy which is based on position-based impedance control model. Two novel improvements were made to achieve a better performance. One is combination of impedance control and explicit force control. The other one is the real-time prediction of the surface’s shape allowing the controller adaptive to arbitrary surfaces.

The result of validation experiments indicates that the estimation of external force and prediction of surface’s shape are credible, and the position-based constant contact force controller in gravitational direction is functional. The accuracy of force tracking is adequate for targeted applications such as polishing, deburring and milling.

The value of this paper lies in three aspects which are sensorless external force estimation, the combination of impedance control and explicit force control and the independence of surface shape information achieved by real-time surface prediction.

This study explores configurations that promote the development of collective economies in China's rural villages and reveals the multiple development pathways that otherwise remain relatively unexamined in the literature.

The authors obtained first-hand representative case data from 20 villages in 12 counties in 5 provinces in East, West and Central China via fieldwork and applied fuzzy set qualitative comparative analysis (fsQCA) to conduct a configurational comparative study of the development of village collective economies.

This paper identifies five factors in the current literature that affect the development of village collectives, based on an “entrepreneur–situation” analytical framework. Using the fsQCA method, this study further obtains two main configurations of conditions that culminate in the growth of rural collective economies in China. The first solution is the “top-down path”: When entrepreneurial leadership (EL), resource endowment (RE) and government assistance (GA) are present, a village collective economy will experience a high level of development, irrespective of policy support (PS) and villagers' participation (VP). The second solution is the “bottom-up path”: When EL, VP and PS are present and GA is not present, a village collective economy will experience a high level of development, irrespective of RE. In both situations, EL stands out as the core condition for the development of village collective economies, implying the need for the government to vigorously cultivate the entrepreneurial skills and aspirations of village cadres.

Taking a configurational perspective and using an fsQCA approach, this research constructs an “entrepreneur–situation” analytical framework to investigate the key combinations of factors and pathways involved in the high level of development of Chinese village collective economies.

This paper aims to consider numerical simulation for radionuclide transport calculations in geological radioactive waste repository.

The nonlinear two-point flux approximation is used to discretize the diffusion flux and has a fixed stencil. The cell-vertex unknowns are applied to define the auxiliary unknowns and can be interpolated by the cell-centered unknowns. The approximation of convection flux is based on the second-order upwind method with a slope limiter.

Numerical results illustrate that the positivity-preserving is satisfied in solving this convection-diffusion system and has a second-order convergence rate on the distorted meshes.

A new positivity-preserving nonlinear finite volume scheme is proposed to simulate the far-field model used in the geological radioactive waste repository. Numerical results illustrate that the positivity-preserving is satisfied in solving this convection-diffusion system and has a second-order convergence rate on the distorted meshes.

The purpose of this paper is to present a weakly supervised learning method to perform health evaluation and predict the remaining useful life (RUL) of rolling bearings.

Based on the principle that bearing health degrades with the increase of service time, a weak label qualitative pairing comparison dataset for bearing health is extracted from the original time series monitoring data of bearing. A bearing health indicator (HI) quantitative evaluation model is obtained by training the delicately designed neural network structure with bearing qualitative comparison data between different health statuses. The remaining useful life is then predicted using the bearing health evaluation model and the degradation tolerance threshold. To validate the feasibility, efficiency and superiority of the proposed method, comparison experiments are designed and carried out on a widely used bearing dataset.

The method achieves the transformation of bearing health from qualitative comparison to quantitative evaluation via a learning algorithm, which is promising in industrial equipment health evaluation and prediction.

The method achieves the transformation of bearing health from qualitative comparison to quantitative evaluation via a learning algorithm, which is promising in industrial equipment health evaluation and prediction.