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In this paper, the mathematical analysis of the robot effective mass is presented. The calculation of this effective mass and its ellipsoid are included. The relationship between the robot effective mass and the external force (collision) affecting the robot end-effector is investigated. The effective mass is analyzed using different robot configurations and different end-effector positions. This analysis is conducted using 2-DOF and 3-DOF planar robots and executed using MATLAB. The results from this analysis prove that the robot effective mass depends on the its configurations and end-effector position. Effective mass can thus be considered as one of the criteria in optimizing robot kinematics and configuration.

Building materials have played a more and more important role in saving building energy since the central government of China set higher standards and requirements for new-constructed and retrofit buildings after 2005. Glazing units, especially energy-saving units including LOW-E coated glazing units and PVB laminated glass, are utilized nation-wide. This paper employs energy simulation to analyze the energy-saving effects of different glazing units in residential buildings in the city of Guangzhou, as an example of hot-humid climate in China. It appeals that the PVB laminated glass can refuse 44 % solar radiation to enter rooms and reduce 40 % of the shading coefficient comparing to clear glass. Meanwhile, in the aspects of operation and design of the HVAC system, 28 % of cooling load, 21 % of installed capacity and 8.6 % of full-load operation time can be saved.

With the development of SoC technology in recent years, the ultra-low power WiFi System on SoC Chip has emerged. As a result, WiFi-based Wireless Sensor Networks come into use, especially used in Automatic Meter Reading. While because the nodes of Wireless Sensor Networks have limited energy supply, smaller storage capability and slower calculation ability, the current WiFi technology cannot be directly applied to WiFi-based Wireless Sensor Networks. The protocols should be upgraded and the security algorithms should be improved to meet the new requests. Firstly, this article describes the network architecture of WiFi-based WSN for AMR system and discusses the reason for using this analogous Mesh architecture. Secondly, the new Hardware architecture of WiFi-based WSN node is designed to realize the AMR system and verify the research work. The node can collect the data of power meter by WiFi and can be powered by a Lithium Battery. Thirdly, on the basis of study work of WiFi original routing protocol HWMP, a new method on improving the energy saving ability of HWMP to adapt the new features of WiFi-based WSN is proposed. And the simulation work on the new routing protocol E-HWMP has been done with NS2 and the simulation results show that the life cycle of the network has been extended to some degree.

A highly efficient nonlinear frequency-domain solution method is proposed and employed to investigate the aerodynamic and aeromechanical performances of an oscillating wind turbine blade aerofoil in this study. Extensive validations of a frequency-domain method against an experiment as well as a typical time-domain solution method are provided in this paper. An experiment is also designed and conducted to measure pressure distributions over an aerofoil as well as to validate the numerical model. Unsteady pressure distributions and aeroelasticity parameters of the oscillating NACA0012 aerofoil are computed at various angles of attack and Reynolds numbers. Results indicate that the difference of unsteady pressure distributions between the two surfaces of the aerofoil becomes larger as the angle of attack is increased, whereas the flow separation on the suction surface is reduced by raising the Reynolds number. The turbulent flow develops in the downstream region due to the laminar vortex shedding at lower Reynolds numbers. It is also revealed that the Reynolds number has an impact on the aeroelasticity, and the aerodynamic damping value is larger at higher Reynolds numbers. The comparison between the frequency-domain method and the time-domain method shows that the frequency-domain method is not only accurate but also computationally very efficient as the computation time is reduced by 90%.

LDPE and HDPE are common materials used within high voltage insulation systems. These materials will be aged after working under high voltage for a long time. The ageing process of these materials may be affected by external factors. The application of repetitive lightning impulse over-voltages is one of these factors and will be considered in this paper. This paper includes the sample preparation process, the ageing of samples under identical conditions and finally the analysis of electrical properties after the ageing process. The obtained results are used to compare the effect of repetitive lightning impulses with these two materials. These results are also used to highlight the possible mechanisms behind the lighting impulse ageing process.

Successful cap and trade programs for SO2 and NOx in the US allocate allowances to large emitters based on a historic base line for a period of up to thirty years. National Allocation Plans in Europe allocate CO2 allowances in an iterative approach first for a three then for a five-year period. The potential updating of the base line creates perverse incentives for operation and investment. Some allowances are also reserved for new entrants further distorting the scheme. We use analytic models and numeric simulations for the UK power sector to illustrate and quantify how these effects contribute to an inflation of the allowance price while reducing utilisation and investment in efficient technologies. The inflated allowance prices are likely to increase the European allowance budget and emissions, e.g. through the Linking Directive. As a result opportunity costs of emitting CO2 are reduced relative to an efficient cap and trade program.

With the introduction of distributed generators (DG), the traditional distribution system characterized by radical network becomes a multi-source one. Therefore the accuracy of the equivalent model of distributed generators directly affects the precision of fault location. To solve this problem, this paper proposed a fault location method based on complex correlation Thevenin equivalent and strong tracking filter (STF) in distribution network with DG. Strong tracking filter (STF) can be used for real-time extraction of fundamental wave phase and amplitude of single phase voltage and current, and fast track the power parameters mutation. The method of complex correlation Thevenin equivalent takes into account the randomness of measurement data, DG impedance and load to overcome measurement error caused by the uncertainty of the data, so that the construction of the DG impedance model is more accurate. Simulation results show that the method of fault location proposed in this paper has advantages of high accuracy and strong robustness.

“Another World Is Possible!” announces a placard held by a demonstrator on an unspecified global justice movement protest. The photograph is the background graphic of an advert. Above it the Shell logo. The advert is for a conference sponsored by the oil giant, entitled “Climate Change: Is Business Doing Enough?” Not so long ago Shell denied climate change altogether. In 1989 it set up the Global Climate Coalition along with several dozen other fossil fuel, vehicle and chemical companies. The avowed aims were to sow doubt about scientific claims concerning global warming and to forestall political efforts to reduce greenhouse gas emissions. The coalition invested heavily in public relations campaigns warning that efforts to reduce emissions by restricting the burning of fossil fuels were misguided and would cause economic disaster. Its efforts helped to put policy making on climate change on hold for years.