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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.

Comparative analysis of three stabilization mechanisms of unstable states of physical systems is presented in this review. These mechanisms are: the quantum Zeno effect, the stabilization of unstable states in an external fast oscillating field (at the example of Kapitza pendulum), and the algorithm called as the principle of whirligig. The common features of these mechanisms, as well as the differences between them, are defined in the paper. In particular, it is shown that the stabilization of quantum systems is possible without involvement of such a notion as the collapse of the wave function. For stabilization there is enough to have such a stabilizing radiation flow when the Rabi frequency of transitions does exceed some frequency. This particular frequency is a magnitude inverse-ly proportional to the lifetime of the state under stabilization. It is shown that stabilization of unstable states by impact of rapidly oscillating forces occurs by non-self-consistent exposure, i.e. the dynamics of stabilizing field is independent of the dynamics of the stabilized state. Stabilization with the principle of whirligig does occur by self-consistent forces, and thus, in many cases stabilization by the use of the principle of whirligig can be more effective.

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.

Chaos and self-similarity are the state-of-the-art problems in various areas of modern science and technology, thus network systems are not exception from this rule. Increasing number of various network protocols, applications and services leads to the fact that network traffic becomes more complex and unpredictable. It has been shown that phenomenon of self-similarity is caused by the properties of network traffic whose origin is the behavior of ТСР protocol. And all this properties became more significant with appearing of the high-speed data transmission technologies. Finally this behavior leads to congestion in network and packet losses as the result of it. But even modern congestion control mechanisms handle such kind of situations quite unfair. For example, as shown by W. Feng et al., TCP Reno loss rate exceeds 5% in a heavily congested network. So it’s easy to calculate that over a Gigabit Ethernet link such loss rate translates into a loss of over 50 Mb/s. Obviously this level of loss rate is unacceptable. However models that describe behavior of information systems sufficiently and give a possibility for scientists to apply all set of classical methods of chaos theory and analyze particular nonlinear dynamical system have not been offered so far. Phase portraits of the studied system were built and Lyapunov exponents for different values of the basic system parameters were calculated. In the present paper a new approach in analysis of the packet switching networks behavior with ТСР protocol is proposed. These networks are analyzed as nonlinear dynamical systems that show chaotic properties at a certain value of parameters.

Comparison results for absorbed dose mapping of the Co60 industrial radiation facility BULGAMMA of Sopharma PLC, Bulgaria using a practical and computational dosimetry are presented in the paper. The gamma radiation facility is based on JS-8500 Co60 irradiator produced by MDS Nordian, Canada. The absorbed dose distributions of gamma rays in an irradiated product on JS-8500 Co60 irradiator have been calculated using the ModeGR Monte Carlo software. The software ModeGR was designed specially for simulation of the absorbed dose distribution within multi-layer packages irradiated with gamma ray from flat panoramic Co60 source rack using a Monte Carlo method. Absorbed dose measurements into containers filled with material using Ethanol Chlorobenzene chemical dosimeters were carried out to validate the software ModeGR. The comparison results show that software ModeGR can be used as a predictive tool for detailed dose mapping in gamma irradiated product.

China has promised to reduce nation’s carbon dioxide emissions in 2020 by at least 40% of its 2005 levels. This paper proposes that interregional industrial shifts might enable China to meet this goal. A Dorfman-Samuelson-Solow model is presented by using an environmental multiregional input-output table of China in a linear programming format and at given national carbon targets, with aim of maximizing national GDP, under constrains for both demand-supply balance and energy-use change within practical limits. In each province, excluding the energy preserved in the secondary energy, final consumption of 39 manufacturing commodities accounted by bottom-up and top-down methods, final consumption of other sectors, energy transition and loss are calculated by converting 20 energy types into carbon emissions. The model suggests that moving the energy and heavy industries out of China’s North Coast would help considerably, GDP losses could be counteracted by raising the output of high-tech industries in the South Coast and of selected services across most of China’s regions. Moreover, adjusting the energy mix toward cleaner resources would alleviate some pressure to reduce carbon emissions of heavy industry throughout China and of the energy industry in Central China. Superseded by a newer version.

Diesel Engine has got an increasingly wide utilization in engineering applications due to its thermal efficiency. Since there are some flaws on design of original engine, the emission performance of diesel engine is poor. In order to improve the performance of the diesel engine, the fuel injection advance angle of original engine is optimized, and a new advance angle of fuel injection is proposed in this paper. By numerical calculation with simulation of software FIRE, the effect of different combustion chamber structures on the cylinder pressure, temperature, accumulated heat release and the parameters such as NOx mass fraction was analyzed. From the simulation results, the optimized fuel injection advance angle had greatly improved the diesel combustion and emission performance. Finally, via experimental verification, the engine with optimized fuel injection advance angle gets better dynamic performance, as well as less emission than original machine.

An in-depth understanding of variations in grassland productivity and forage-livestock balance is the basis of ecological barrier construction and ecosystem conservation in the Qinghai-Tibetan Plateau. Using an ecohydrological process-based model VIP with remotely sensed vegetation index and leaf area index, we simulated the spatial and temporal variations of grassland productivity in the Tibetan Plateau in 2000-2018. The variations in the status of forage-livestock balance at the county level were analyzed, combining with agriculture and animal husbandry statistics in the same period. The results showed that the mean annual net primary productivity (NPP) of grassland in the Tibetan Plateau was 158.4 g C·m-2·a-1, which had increased significantly in the past 20 years, with a significant increase in 44.7% of the total area. Climate warming, increased precipitation, prolonged growing season, and elevated carbon dioxide concentration were main driving forces for grassland productivity. The mean theoretical livestock carrying capacity estimated based on pasture yield was 1.17 SU·hm-2, with a growth rate of 0.011 SU·hm-2. The situation of overgrazing in the Tibetan Plateau had generally improved since 2000. The proportion of counties with severe overgrazing had dropped to less than 20%. In areas with more severe overgrazing, animal husbandry's maintenance and development mainly relied on supplementation of crop straw. The results could provide a scientific basis for regional agricultural and animal husbandry structural adjustment and environmental protection.

To explore the effects of different densities of mixed-cropping on 13C-photosynthate distribution and grain yield of maize, we measured photosynthetic characteristics, 13C-photosynthate distribution, dry matter accumulation, and grain yield under different planting densities (LD, 67500 plants·hm-2 and HD, 97500 plants·hm-2) under mixed-cropping (M, 1:1, 2:2) and monoculture of Zhengdan958 (ZD) and Denghai605 (DH). The results showed that with the increases of planting density, grain yield, 13C-photosynthate allocation to grain, dry matter accumulation, and leaf area index (LAI) increased, but the chlorophyll content and net photosynthetic rate decreased. No significant difference was observed between the monoculture and mixed-cropping at the density of 67500 plants·hm-2. However, at 97500 plants·hm-2, LAI, chlorophyll content, net photosynthetic rate and dry matter accumulation in mixed-cropping were higher than that in monoculture. Mixed-cropping promoted the transport of dry matter from the vegetative organs such as stem to the grain and the distribution of 13C-photosynthates to grain. Grain yield of summer maize significantly increased in mixed-cropping due to the increase of 1000-grain mass. Under high plant density, the mixed-cropping could enlarge photosynthetic area, maintain higher net photosynthetic rate, increase dry matter accumulation, improve the distribution of dry matter, promote the distribution of 13C-photosynthates to grains and thus increase the grain yield. Our results indicated that mixed-cropping could significantly increase the yield of close planting summer maize in Huang-Huai-Hai Plain.