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This paper aims to describe a simple low-pass filter to suppress torque pulsation and current harmonics in permanent magnet synchronous motor (PMSM) drives.

For the control of the PMSM, a field-oriented control algorithm is always used. The proposed filter is actually a resistance, inductance, capacitance (RLC) filter. At the output of the inverter and the input of PMSM, an RLC filter is connected. This filter suppresses current harmonics through filtering phase voltage harmonics. Analysis of the filter is achieved through frequency characteristics analysis.

This filter can effectively filter out the harmonic of phase voltage. Both the simulation and experiment results show that the proposed filter can effectively suppress torque pulsation and current harmonics in PMSM drives. Also, the method of selecting filter parameters and the whole control system are very simple.

The filter increases the design cost of the system.

The harmonics and torque ripple of phase current are greatly suppressed. Also, the loss of the PMSM reduced.

The method of selecting filter parameters and the analysis of the proposed filter are proposed for the first time.

The reconstructed skull of the primate fossil Homunculus, a Miocene New World monkey from Argentina, offers unique opportunities for further study and has revealed information that could not be observed or appreciated on the original damaged specimens. This paper presents the process that applies the rapid prototyping methodology to reconstruct and produce such a physical model of the Homunculus’s skull. A laser scanner is used to digitize three pieces of sharp epoxy casts from the left facial skull and the mandible, which were broken apart during fossilization. Commercial software systems are used to develop image models of the fully reconstructed face and lower jaw. A stereolithography process is used to build the physical model.

In the face of solving the urban traffic congestion problem radically, emphasis has been laid on the research on slow traffic planning of urban built environment. Hence, research on slow traffic demand forecasting can provide a basis for the planning of urban slow traffic systems. Based on land use, the overall planning of the new Guangming (GM) district, and the population prediction results, the slow traffic demand within the scope of the new district was forecasted by combining the per capita trip frequency, and the spatial distribution of the slow traffic flow of the new GM district was forecasted per the forecasted demand quantity for slow traffic. The following research conclusions were obtained. Within the new GM district, the correlation of the total demand for slow traffic with the land use functions and population distribution was high, and the cross-zone traffic was mainly decided by the land usage of this district. The cross-unit slow traffic flow was concentrated in the Gongming central, Guangming central, high-tech zone, and Yutian zones. This research provides a guideline for the layout of slow traffic facilities in the future.

The purpose of this paper is to track the changes of leadership attributes during the process of social development from 1998 to 2008 in China, and then to explore whether the significant events have potential impacts on the changes of leadership attributes during this time.

The authors conducted two studies through qualitative approach, based on data collected from Chinese official newspapers (People's Daily and Guangming Daily) covering 216 stories (90 stories in Study 1 and 126 stories in Study 2). The first study focuses on comparing the leadership attributes in 2008 with those in 1998 and 1988 presented in previous research to find out the changes. In the second study, the most significant events are selected during the period of 1998‐2008 and their effects on the changes of leadership attributes are examined.

The findings show that leadership attributes changed during the ten years and some new attributes are advocated in China. Furthermore, the changes of leadership attributes, especially for non‐business leaders, relate to the occurrence of significant events and reflect the changes of government policies.

Although some literature has explored leadership attributes in China, this study contributes to the extant research in two ways. First, it promotes the use of existing documents as data sources of longitudinal study to track the changes of leadership attributes. Second, it advances the line of inquiry of leadership attributes in China by concentrating on the factors driving those changes.

This paper aims to tele-operate the movement of an unmanned aerial vehicle (UAV) in the obstructed environment with asymmetric time-varying delays. A simple passive proportional velocity errors plus damping injection (P-like) controller is proposed to deal with the asymmetric time-varying delays in the aerial teleoperation system.

This paper presents both theoretical and real-time experimental results of the bilateral teleoperation system of a UAV for collision avoidance over the wireless network. First, a position-velocity workspace mapping is used to solve the master-slave kinematic/dynamic dissimilarity. Second, a P-like controller is proposed to ensure the stability of the time-delayed bilateral teleoperation system with asymmetric time-varying delays. The stability is analyzed by the Lyapunov–Krasovskii function and the delay-dependent stability criteria are obtained under linear-matrix-inequalities conditions. Third, a vision-based localization is presented to calibrate the UAV’s pose and provide the relative distance for obstacle avoidance with a high accuracy. Finally, the performance of the teleoperation scheme is evaluated by both human-in-the-loop simulations and real-time experiments where a single UAV flies through the obstructed environment.

Experimental results demonstrate that the teleoperation system can maintain passivity and collision avoidance can be achieved with a high accuracy for asymmetric time-varying delays. Moreover, the operator could tele-sense the force reflection to improve the maneuverability in the aerial teleoperation.

A real-time bilateral teleoperation system of a UAV for collision avoidance is performed in the laboratory. A force and visual interface is designed to provide force and visual feedback of the slave environment to the operator.

The paper aims to construct a method to simulate the relationship between the parameters of soil properties and the area of sliding mass of the true slip surface of a landslide.

The smoothed particle hydrodynamics (SPH) algorithm is used to calibrate a response surface function which is adopted to quantify the area of sliding mass of the true slip surface for each failure sample in Monte Carlo simulation. The proposed method is illustrated through a homogeneous and a heterogeneous cohesive soil slope.

The comparison of the results between the proposed method and the traditional method using the slip surface with minimum factor of safety (FS_min) to quantify the failure consequence has shown that the landslide risk tends to be attributed to a variety of risk sources, and that the use of a slip surface with FS_min to quantify the consequence of a landslide underestimates the landslide risk value. The difference of the risk value between the proposed method and the traditional method increases dramatically as the uncertainty of soil properties becomes significant.

A geotechnical engineer could use the proposed method to perform slope failure analysis.

The failure consequence of a landslide can be rationally predicted using the proposed method.

This study aims to investigate the effect of post-treatment on anti-corrosion performance of Al coating on the surface of Ti-6Al-4V (TC4) fastener.

The Al coatings with different layer structures were prepared on TC4 by middle-frequency and direct-current combined magnetron sputtering. The cross-sectional morphology and surface roughness of coatings were characterized by scanning electron microscope and atomic force microscope. The corrosion resistance was evaluated by electrochemical method. The monolayer coating was post-treated by Alodine chemical conversion, Ar⁺ bombardment and a combination of two methods above.

The results show that the interfaces in bilayer and trilayer coatings reduce the defects. Ar⁺ bombardment reduces the corrosion current density, and Alodine chemical conversion leads to a higher pitting corrosion potential. The combined post-treatment has the highest polarization resistance.

The corrosion resistance of the Al coating is enhanced as the layer quantity increases. The combination of two post-treatments, Ar⁺ bombardment and Alodine chemical conversion, could achieve an overall improvement in corrosion resistance of Al coating.

This paper aims to develop an efficient algorithm combining straightforward response surface functions with Monte Carlo simulation to conduct seismic reliability analysis in a systematical way.

The representative slip surfaces are identified and based on to calibrate multiple response surface functions with acceptable accuracy. The calibrated response surfaces are used to determine the yield acceleration in Newmark sliding displacement analysis. Then, the displacement-based limit state function is adopted to conduct seismic reliability analysis.

The calibrated response surface functions have fairly good accuracy in predicting the yield acceleration in Newmark sliding displacement analysis. The seismic reliability is influenced by such factors as PGA, spatial variability and threshold value. The proposed methodology serves as an effective tool for geotechnical practitioners.

The multiple sources of a seismic slope response can be effectively determined using the multiple response surface functions, which are easily implemented within geotechnical engineering.

Selecting the development and renewal of residential areas has caused significant confusion in the construction of a new countryside with the rapid development of information and computer technology. The application of digital assistive technology in traditional settlement planning has received increasing attention in recent years. Thus, this study combined the folk culture of traditional settlement, local unique landform, and climate environment. Digital technology was used as the starting point. Traditional settlement planning and green update design were studied with the help of a digital building software. The planning of Shuanglong Village and the residential green renewal design were taken as examples. Shuanglong Village's overall planning and design was presented and showed that its road traffic was clearly planned. The rational use of local land was attained. The landscape of Shuanglong Village was then designed. Practice has proven that the research on traditional settlement planning and green renewal design based on digital assistive technology can provide the basis for such activities.

With the development of economy and the progress of science and technology, the function of Luoyang city is constantly enriched and expanded. The city is no longer a simple area for people to live in. The function structure of the city is affected by the external factors and is constantly expanding. Urban logistics is one of the important influencing factors. To more comprehensively and accurately understand the status and role of logistics network space in urban planning, the characteristics and development law of urban logistics structure from the theoretical point of view are analyzed in this paper with Luoyang City as the research background. The city logistics function is determined as one of the main factors affecting the economic growth of the city is determined through the literature search method, consulting professionals and other research methods. Urban road planning and design are the focus of the study; the planning and development of urban logistics road network in Luoyang City are compared and analyzed. In full consideration of the necessity of the optimization of the urban logistics network space, the preliminary optimization scheme design and suggestion of Luoyang logistics is introduced. At the end of this paper, the sustainable development and the status of the future urban logistics function are analyzed and prospected. Continuous research and analysis of multiple subjects and angles are still needed.