Dynamic-static coupling analysis on rockburst mechanism in jointed rock mass

A numerical code called RFPA-Dynamics was used to study the rockburst mechanism under dynamic load based on coupled static-dynamic analysis.The results show that dynamic disturbance has a very distinct triggering effect on rockburst.Under the dynamic load,rockburst is motivated by tensile stress formed by the overlapping of dynamic waves in the form of instantaneous open and cutting through of cracks in weak planes and pre-damaged areas.Meanwhile,the orientation of joint sets has an obvious leading effect on rockburst locations.Finally,a higher initial static stress state before dynamic loading can cause more pre-damaged area,thus leading to a larger rockburst scope.

Kinematic analysis of a humanoid robot CHP-1 and selection of motors in consideration of cooperative motion

A lower-part humanoid robot CHP-1 with 12 degree-of-freedom of motion has been developed for cooperative motion,such as pushing or lifting an object.The capability of the robot is mainly dependent on the performance of the motors,thus the motors need to be properly selected.For the purpose,the kinematics of the robot was analyzed,and a number of simulations for two kinds of cooperative motions were carried out.The torques required at each motor of the robot under external forces were obtained.Here,the external forces were also estimated through simulation and literature survey.On the basis of the torques found,the selection of motors was finally suggested,and the motors are to be installed to the humanoid robot.

Cooperative Sensing and Distributed Control of a Diffusion Process Using Centroidal Voronoi Tessellations

This paper considers how to use a group of robots to sense and control a diffusion process.The diffusion process is modeled by a partial differential equation (PDE),which is a both spatially and temporally variant system.The robots can serve as mobile sensors,actuators,or both.Centroidal Voronoi Tessellations based coverage control algorithm is proposed for the cooperative sensing task.For the diffusion control problem,this paper considers spraying control via a group of networked mobile robots equipped with chemical neutralizers,known as smart mobile sprayers or actuators,in a domain of interest having static mesh sensor network for concentration sensing.This paper also introduces the information sharing and consensus strategy when using centroidal Voronoi tessellations algorithm to control a diffusion process.The information is shared not only on where to spray but also on how much to spray among the mobile actuators.Benefits from using CVT and information consensus seeking for sensing and control of a diffusion process are demonstrated in simulation results.

Constraints Hindering the Adoption of Scientific Dairy Farming Practices by Members and Non-members of Dairy Co-operative Societies （DCS）/Milk Producer Institutions （MPI）

The present study was conducted in four districts of Telangana State of India with 120 respondents in which 60 were members and other 60 were non-members of DCSs （Dairy Co-operative Societies）/MPIs （Milk Producer Institutions）. Constraints perceived in dairy farming and suggestions elicited by members and non-members were noted, tabulated and analyzed. The major constraints perceived by half or more than half of members were scarcity of water （91.67%）, lack of green fodder （88.33%）, preferring NS （natural service） than AI （Artificial Insemination） （83.33%）, negligence in feeding pregnant and dry animals （81.37%）, insufficient loan amount （78.33%）, tendency to feed only grass and brans （71.67%）, lack of availability of sufficient labour （70.00%）, lack of remunerative price for milk （66.67%）, high cost of feed （61.67%）, lack of fodder conservation （55.00%） and high cost of animals （50.00%）. Whereas major constraints perceived by non-members were scarcity of water （96.67%）, lack of green fodder （93.33%）, preferring NS than AI （88.33%）, lack of availability of sufficient labour （85.00%）, negligence in feeding pregnant and dry animals （83.33%）, tendency to feed only grass and brans （78.33%）, high cost of animals （75.00%）, complex procedure for obtaining loans （71.67%） and high cost of feed （66.67%）. Suggestions elicited by members majorly were providing subsidy for purchase of animals/providing loans on par with the cost of animal （81.67%）, enhancing the procurement price （70.00%）, providing more incentives （60.00%）, encouraging calf rearing （58.33%） and conducting frequent animal health camps （50.00%）. In case of non-members major suggestions elicited were conducting frequent animal health camps （68.33%） and providing subsidy on purchase of animals/providing loans on par with the cost of animal （58.33%）. Considering the above constraints perceived and suggestions elicited by dairy farmers a proper linkage strategy should be developed among private and public sectors in providing need based services to the dairy farmers.

Learning L2 English in Tandem Partnerships On-Line

Tandem learning via email and computer-mediated communication activities flanked standard frontal English lessons for Italian adult learners in Italy. It is here suggested that the combination of tandem learning, various communication activities performed on-line, and standard courses help mature students to boost their self-esteem, give them more autonomy, and enhance their motivation. Tandem learning, which is based on the principles of reciprocity and autonomy, is ideally suited for adult students. It helps overcome the problems connected to the affective reactions of adults, and at the same time, being content driven, offers a more natural setting to learn an L2 （second language） on a mutual supportive basis.

Power Ramping Schemes for M2M and H2H Co-existing Scenario

To analyze and reduce the impact of Machine-to-Machine (M2M) Devices (MDs) on the traditional Human-to-Human (H2H) users for the blending scenario, where both M2M and H2H services coexist in the current Universal Mobile Telecommunication System (UMTS) and perform the Random Access (RA) procedure simultaneously, a comprehensive RA analysis model of RA is proposed in this paper. Further, a power ramping strategy based on the logarithm for M2M is proposed. The efficiency of both the existing and proposed scheme is assessed through a simulation across several metrics, including average target power, throughput, blocking probability, and delay statistics. Numerical results show that the proposed algorithm can ensure a minimal impact on H2H communication while maintaining the throughput of the M2M communication. Meanwhile, because of its low energy consumption, this algorithm has a significant guide value for real-world applications.

Single carrier frequency domain equalization and diversity combining for cooperative systems

A low-complexity single carrier frequency-domain equalizer （SC/FDE） and diversity combining method for cooperative systems with demodulate-and-forward relaying over frequency-selective channels is proposed. At the relay nodes, linear SC/FDE is adopted and normalized correlation coefficlent is mtrodueed to derive an equivalent source-to-relay-destination （S-R-D） channel that is highlighted in this study. At the destination, a joint SC/FDE and diversity combining receiver is proposed by utilizing the equivalent S-R-D channel. Simulation results demonstrate the superiority of the proposed SC/FDE scheme over the straightforward SC/FDE which ignores the decisions errors at the intermediate relay nodes.

Modeling and Analysis of Electrostatically Actuated MEMS under Combined Nonlinearities, Lorentz Force, and Mechanical Shock

This paper shows an analysis ofMEM S （micro electro mechanical systems） due to Lorentz force and mechanical shock. The formulation is based on a modified couple stress theory, the von Karman geometric nonlinearity and Reynolds equation as well. The model contains a silicon microbeam, which is encircled by a stationary plate. The non-dimensional governing equations and associated boundary conditions are then solved iteratively through the Galerkin weighted method. The results show that pull-in voltage is dependent on the geometry nonlinearity. It is also demonstrated that by increasing voltage between the silicon microbeam and stationary plate, the pull-in instability happens.

公共物品理论研究中的实验方法

从20世纪70年代开始,一些经济学家开始将实验方法引入到公共物品的研究中,对这一领域中的一些基本观点进行实证检验,从而将公共物品研究从单纯的逻辑推演阶段发展到了实证检验阶段。

Effect of electrolyzed oxidizing water and hydrocolloid occlusive dressings on excised burn-wounds in rats

Objective: To study the efficacy of electrolyzed oxidizing water ( EOW ) and hydrocolloid occlusive dressings in the acceleration of epithelialization in excised burn-wounds in rats.Methods: Each of the anesthetized Sprague-Dawley rats (n = 28) was subjected to a third-degree burn that covered approximately 10% of the total body surface area. Rats were assigned into four groups: Group Ⅰ ( no irrigation), Group Ⅱ (irrigation with physiologic saline), Group Ⅲ ( irrigation with EOW ) and Group Ⅳ ( hydrocolloid occlusive dressing after EOW irrigation). Wounds were observed macroscopically until complete epithelialization was present, then the epithelialized wounds were examined microscopically. Results: Healing of the burn wounds was the fastest in Group Ⅳ treated with hydrocolloid occlusive dressing together with EOW. Although extensive regenerative epidermis was seen in each Group, the proliferations of lymphocytes and macrophages associated with dense collagen deposition were more extensive in Group Ⅱ, Ⅲ and IV than in Group Ⅰ. These findings were particularly evident in Group Ⅲ and Ⅳ.Conclusions: Wound Healing may be accelerated by applying a hydrocolloid occlusive dressing on burn surfaces after they are cleaned with EOW.

A New Cooperation Mechanism of Kinesin Motors when Extracting Membrane Tube

Membrane tubes are important functional elements for riving cells. Experiments have found that membrane tubes can be extracted from giant lipid vesicles by groups of kinesin. How these motors cooperate in extracting the membrane tube is a very important issue but still unclear so far. In this paper, we propose a cooperation mechanism called two-track-dumbbell model, in which kinesin is regarded as a dumbbell with an end （tail domain） tethered on the fluid-like membrane and the other end （head domain） stepping on the microtubule. Taking account of the elasticity of kinesin molecule and the excluded volume effect of both the head domain and the tail domain of kinesin, which are not considered in previous models, we simulate the growth process of the membrane tube pulled by kinesin motors. Our results indicate that in the case of strong or moderate exclusion of motor tails, the average number of motors pulling the tube can be as high as 9 and thus motors moving along a single microtubule protofilament can generate enough force to extract membrane tubes from vesicles. This result is different from previous studies and may be tested by future experiments.

Effect of Aspiration and Mean Gain on the Emergence of Cooperation in Unidirectional Pedestrian Flow

When more than one pedestrian want to move to the same site, conflicts appear and thus the involved pedestrians play a motion game. In order to describe the emergence of cooperation during the conflict resolving process, an evolutionary cellular automation model is established considering the effect of aspiration and mean gain. In each game, pedestrian may be gentle cooperator or aggressive defector. We propose a set of win-stay-lose-shrift （WSLS） like rules for updating pedestrian＇s strategy. These rules prescribe that if the mean gain of current strategy between some given steps is larger than aspiration the strategy keeps, otherwise the strategy changes. The simulation results show that a high level aspiration will lead to more cooperation. With the increment of the statistic length, pedestrians will be more rational in decision making. It is also found that when the aspiration level is small enough and the statistic length is large enough ail the pedestrian will turn to defectors. We use the prisoner＇s dilernma rnodel to explain it. At last we discuss the effect of aspiration on fundamental diagram.

Counter-Rotating Type Pump-Turbine Unit Cooperating with Wind Power Unit

This serial research proposes the hybrid power system combined the wind power unit with the counter-rotating type pump-turbine unit,to provide the constant output for the grid system,even at the suddenly fluctuating/turbulent wind.In this paper,the tandem impellers of the counter-rotating type pumping unit was operated at the turbine mode,and the performances and the flow conditions were investigated numerically and experimentally.The 3-D turbulent flows in the runners were simulated at the steady state condition by using the commercial CFD code of ANSYS-CFX ver.12 with the SST turbulence model.While providing the pump unit for the turbine mode,the maximum hydraulic efficiency is close to one of the counter-rotating type hydroelectric unit designed exclu-sively for the turbine mode.Besides,the runner/impeller of the unit works evidently so as to coincide the angularmomentum change through the front runners/impellers with that through the rear runners/impellers,namely to take the axial flow at not only the inlet but also the outlet without the guide vanes.These results show that this type of unit is effective to work at not only the pumping but also the turbine modes.

Coarse-grained Reuse of Workflows Based on Teamwork and Activity-Pattern-Oriented

Flexibility plays an important part in the application of the workflow management system and has become one of the major research hotspots in this field recently. When adapting a workflow process definition to specific needs or changing the structure of the workflow process as a result of evolutionary change, coarse-grained reuse of work- flow is of significance to the reduction of the work effort, modeling system and enhancing the reliability of their work. Based on decomposition of workflow tasks and teamwork, this paper proposes an approach to describing interoperability behavior between roles in teamwork by using activity-pattern. In activity-pattern, abstract mechanisms of activity specialization and activity aggregation are presented, enabling reuse of workflow by means of reuse of interoperability behavior between roles. The experimental system shows that our approach presented is feasible.