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This paper aims to propose a hybrid force/position controller based on the adaptive variable impedance.

First, the working space is divided into a force control subspace and a position subspace, the force control subspace adopts the position impedance control strategy. At the same time, the contact force model between the robot and the surface is analyzed in this space. Second, based on the traditional position impedance, the model reference adaptive control is introduced to provide an accurate reference position for the impedance controller. Then, the BP neural network is used to adjust the impedance parameters online.

The experimental results show that compared with the traditional PI control method, the proposed method has a higher flexibility, the dynamic response accommodation time is reduced by 7.688 s and the steady-state error is reduced by 30.531%. The overshoot of the contact force between the end of robot and the workpiece is reduced by 34.325% comparing with the fixed impedance control method.

The proposed control method compares with a hybrid force/position based on PI control method and a position fixed impedance control method by simulation and experiment.

The adaptive variable impedance control method improves accuracy of force tracking and solves the problem of the large surfaces with robot grinding often over-polished at the protrusion and under-polished at the concave.

This paper aims to investigate the effects of the pia matter on cerebral cortical folding.

A three-layer buckling simulation model composited by the white matter, gray matter and the pia matter is adopted to analyze the effect of the pia matter on cortical folding. The volume growth of brain tissues is simulated using thermal expansion. The effects of the pia matter growth rate, thickness and stiffness on cortical folding is investigated.

The simulation results show that all of these three aforementioned factors of pia matter have obvious effects on cerebral cortical folding. Especially, the thickening of the pia matter may lead to cortical folding malformation such as polymicrogyria, which is in good agreement with the recent reported anatomical findings.

The three-layer model in this paper composited by the white matter, gray matter and the pia matter is different from the usually used two-layer model only composited by the white matter and gray matter. This three-layer model has successfully validated the effect of the pia matter on cerebral cortical folding. The simulation results can explain the anatomical findings very well.

The interruption event will seriously affect the normal operation of urban rail transit lines,causing a large number of passengers to be stranded in the station and even making the train stranded in the interval between stations. This study aims to reduce the impact of interrupt events and improve service levels.

To address this issue, this paper considers the constraints of train operation safety, capacity and dynamic passenger flow demand. It proposes a method for adjusting small loops during interruption events and constructs a train operation adjustment model with the objective of minimizing the total passenger waiting time. This model enables the rapid development of train operation plans in interruption scenarios, coordinating train scheduling and line resources to minimize passenger travel time and mitigate the impact of interruptions. Regarding the proposed train operation adjustment model, an improved genetic algorithm (GA) is designed to solve it.

The model and algorithm are applied to a case study of interruption events on Beijing Subway Line 5. The results indicate that after solving the constructed model, the train departure intervals can be maintained between 1.5 min and 3 min. This ensures both the safety of train operations on the line and a good match with passengers’ travel demands, effectively reducing the total passenger waiting time and improving the service level of the urban rail transit system during interruptions. Compared to the GA algorithm, the algorithm proposed in this paper demonstrates faster convergence speed and better computational results.

This study explicitly outlines the adjustment method of using short-turn operation during operational interruptions, with train departure times and station stop times as decision variables. It takes into full consideration safety constraints on train operations, train capacity constraints and dynamic passenger demand. It has constructed a train schedule optimization model with the goal of minimizing the total waiting time for all passengers in the system.

The purpose of this paper is to investigate the friction and wear mechanisms in copper-based self-lubricating composites with MoS₂ as the lubricating phase, which provides a theoretical basis for subsequent research on high-performance copper-based self-lubricating materials.

Friction tests were performed at a speed of 100 r/min, a load of 10 N, a friction radius of 5 mm and a sliding speed of 30 min. Friction experiments were carried out at RT-500°C. The phase composition of the samples was characterized by X-ray diffraction of Cu Ka radiation, and the microstructure, morphology and elemental distribution were characterized by scanning electron microscopy and energy dispersive spectroscopy. Reactants and valences formed during the wear process were analyzed by X-ray photoelectron spectroscopy.

The addition of MoS₂ can effectively improve friction-reducing and anti-wear action of the matrix, which is beneficial to form a lubricating film on the sliding track. After analyzing different changing mechanism of the sliding tracks, the oxides and sulfides of MoS₂, MoO₂, Cu₂O, CuO and Ni(OH)₂ were detected to form a synergetic lubricating film on the sliding track, which is responsible for the excellent tribological properties from room to elevated temperature.

For self-lubrication Cu–Sn–Ni–MoS₂ material in engineering field, there are still few available references on high-temperature application.

This paper provides a theoretical basis for the following research on copper-based self-lubricating materials with high performance.

With this statement, the authors hereby certify that the manuscript is the results of their own effort and ability. They have indicated all quotes, citations and references. Furthermore, the authors have not submitted any essay, paper or thesis with similar content elsewhere. No conflict of interest exits in the submission of this manuscript.

This paper aims to explore the commodity transshipment planning among customers, which is commonly observed in production/sales enterprises to save the operational costs.

A mixed integer programming (MIP) model is built and five types of valid inequalities for tightening the solution space are derived. An improved variable neighborhood search (IVNS) algorithm is presented combining the developed multistart initial solution strategy and modified neighborhood local search procedure.

Experimental results demonstrate that: with less decision variables considered, the proposed model can solve more instances compared to the existing model in previous literature. The valid inequalities utilized to tighten the searching space can efficiently help the model to obtain optimal solutions or high-quality lower bounds. The improved algorithm is efficient to obtain optimal or near-optimal solutions and superior to the compared algorithm in terms of solution quality, computational time and robustness.

This research not only can help reduce operational costs and improve logistics efficiency for relevant enterprises, but also can provide guidance for constructing the decision support system of logistics intelligent scheduling platform to cater for centralized management and control.

This paper develops a more compact model and some stronger valid inequalities. Moreover, the proposed algorithm is easy to implement and performs well.

Neuroarchitecture is a new interdisciplinary research field combining neuroscience and architecture that has developed and expanded since 2000. Neuroarchitecture originated from the divergence of previous multidisciplinary studies on the relationship between humans and the environment. However, scoping reviews of neuroarchitecture in relation to the experience of the built environment are lacking. Thus, this study aimed to provide the background and research trends of neuroarchitecture to contribute to discussions on the built environment.

A general form of scoping review was adopted, following the PRISMA-ScR checklist. For this scoping review emphasizing the embodied implication of neuroarchitecture for the built environment, an evaluation framework was developed consisting of four categories: health, performance, aesthetics and emotion.

This study explores objective techniques, including electroencephalography and functional magnetic resonance imaging, electrocardiogram, electrodermal activity and saliva cortisol, to measure neurophysiological impacts, adopting real, virtual and images of environmental settings. An in-depth review of 25 selected papers revealed the existing empirical research on neuroarchitecture using human physiological measurement tools and representational environment settings to examine the impact of human–environment relationships.

A meta-analysis of theoretical and intervention studies on neuroarchitecture that investigates the multisensory characteristics of the environment is lacking. In addition, the development and application of wearable tools to meet the needs of real environment settings can improve the effectiveness of neurophysiological measurement tools.

The purpose of this paper is to separate households into several types based on their features, and then to further investigate determinants of household fish consumption in China by figuring out consumption preference divergences between types of households under the effects of economic and socio-demographics factors.

This paper first applies Multiple Correspondence Analysis to separate the modalities of variables and households according to their features, with health knowledge and time constraint of a spouse highlighted. Then, the transcribed principal information of both variables and households has been added into Marshallian demand function with fish price, income, child effect, and health status for identification of factors on household fish demand. The robust fixed effect and robust random effect GLS regression has been conducted.

The paper provides empirical insights about what and how factors affect household fish consumption. It suggests that, for all households, pork is still a main substitution of fish, fish consumption regarding to each household should be constant, and fish consumption differs a lot between provinces. For households with higher dietary knowledge, the authors found that increase of income, the existence of adolescent would cause an increase in fish consumption, while illness of household member makes a decrease in fish consumption. For households with working women who have higher opportunity cost of time pursue much more convenience, then consume less fish at home than their counterparts.

The increasing variety in consumer’s dietary need makes the understanding of which becoming much more difficult than before. This paper uses three-wave panel data with households spread over nine provinces in China, but the results still has its limitation since china is the one with vast in territory and residents. In the future, the difference between urban and rural area in fish consumption need further research.

The paper reveals the common determinants of fish consumption in China, and makes a further clear answer by a further discussion on different household types. The results have rather high implications for making targeted policy or precisely forecasting a future fish demand in China, which will rather be helpful for fishery industry development in China.

This paper fulfills an identified need to study the divergence of determinants or the impact degree of different factors on fish consumption in China by household types. An increasing trend of food away from home has significant effect on how to count household size in food consumption studies, and the identification of persday in this study shows its advantages in dealing with this issue, which makes a contribution on resolve the overestimation of household size issue.

The purpose of this paper is to explore how far plans to “modernize” hospital management in China are converging toward a global model of new public management (NPM) or represent a distinctive pathway.

This paper draws on a systematic review of available secondary sources published in English and Chinese to describe both the nature and trajectory of hospital management reforms in China.

In China, while public hospital reforms bear many of the hallmarks of the NPM, they are distinctive in two key respects. First, the thrust of current reforms is to partially reverse, not extend, the trend toward marketization in order to strengthen the public orientation of public hospitals. Second is a marked gap between the rhetoric and reality of empowering managers and freeing them from political control.

This paper develops a framework for understanding the drivers and obstacles to hospital management reforms in China that is useful for managers, clinicians and policy makers.

In China, few authors have considered NPM reform in relation to healthcare. This paper contributes in better understanding current reforms taking place in China’s expanding healthcare sector and locates these within broader theoretical and policy debates.

The purpose of this paper is to develop an efficient numerical method to study the complex crack initiation and propagation in linear elastic multiphase composites.

A phase field method is developed to study the complex fracture behavior in multiphase composites. A damage threshold is introduced for referring crack initiation in the proposed method. The damage threshold is assigned as a material property so that different composite components possess different thresholds. In this manner, smooth transition from crack initiation to propagation is revealed.

The proposed method is used to investigate complex crack evolution in mesoscale cementitious composite, which consists of aggregates, matrix and void pores. From a mesoscale point of view, it is found that cracks prefer to evolve within the matrix phase. As a crack encounters an aggregate, it tends to bypass the aggregate and evolve along the interface. Cracks tend to avoid to penetrate through aggregates. Also, cracks tend to be attracted by void pores. From a mesoscale point of view, it is revealed that the elastic modulus and strength of concrete models are closely related to porosity.

A criterion with a damage threshold is introduced to the proposed method. The criterions with and without a damage threshold are compared with each other in details. The proposed method is proven to be a useful tool to study mechanical behavior and crack evolution of brittle multiphase composites.

The purpose of this paper is to calculate the Hugoniot relations of polyurea; also to investigate the atomic-scale energy change, the related chain conformation evolution and the hydrogen bond dissociation of polyurea under high-speed shock.

The atomic-scale simulations are achieved by molecular dynamics (MD). Both non-equilibrium MD and multi-scale shock technique are used to simulate the high-speed shock. The energy dissipation is theoretically derived by the thermodynamic and the Hugoniot relations. The distributions of bond length, angle and dihedral angle are used to characterize the chain conformation evolution. The hydrogen bonds are determined by a geometrical criterion.

The Hugoniot relations calculated are in good agreement with the experimental data. It is found that under the same impact pressure, polyurea with lower hard segment content has higher energy dissipation during the shock-release process. The primary energy dissipation way is the heat dissipation caused by the increase of kinetic energy. Unlike tensile simulation, the molecular potential increment is mainly divided into the increments of the bond energy, angle energy and dihedral angle energy under shock loading and is mostly stored in the soft segments. The hydrogen bond potential increment only accounts for about 1% of the internal energy increment under high-speed shock.

The simulation results are meaningful for understanding and evaluating the energy dissipation mechanism of polyurea under shock loading, and could provide a reference for material design.