Advanced Materials Research Vols. 403-408

Abstract: By the thin shell theory, for the casing damage caused by formation creep at local ring cementing lacuna, differential equations for force and deformation of casing was established and the unknown boundary issues with rigid constraints around the cement sheath was discussed. The border issue and the displacement and stress solutions were determined by displacement method and semi-converse solution. The distribution of the stress was analyzed. The results show that risk locations of casing damage are mostly at the centre and the edge of the lacuna. The conditions of casing strength are established by the above.

Abstract: Analysised and researched for the power control problem in Ad Hoc network, and Proposed an improved power control protocol based on 802.11MAC layer of CSMA /CA mechanism . The algorithm increased the transmission power value and the received power threshold in the RTS/CTS control packets, the node and its adjacent node can determined the data packet transmission power and received power accorded it, Thus effectively reduced the nodes between the hidden terminal and exposed terminal interference, and can reduced the power consumption of wireless nodes. It is compared with the IEEE 802.11 MAC protocol by simulation. The results show that the power control protocol can improve the system end to end throughput performance, and minimize the power consumption of wireless nodes, so as to saved the network power consumption .

Abstract: Biomass energy is an important component of household energy consumption in rural areas of China. However, under current exploitation levels, the energy source is beset with both theoretical and practical challenges, and its sustainable utilization is seriously restricted. One key to solving this problem is the establishment of a theoretical framework for the sustainable use of biomass energy by rural households. Based on the new viewpoint that biomass energy is a type of ‘weakly’ renewable energy, this paper provides the first theoretical basis outlining the sustainable use of biomass energy in rural households, including systems theory, the theory of ecological carrying capacity, the utility theory, the theory of ecological economics and the theory of natural resource values. The relationships among these theories are also discussed. In addition, four conditions governing the theoretical sustainable use of biomass energy by rural households are analyzed: the sustainability of the resource supply, the sustainability of biomass energy production, the sustainability of consumer acceptance, and the sustainability of ecological environmental effects.

Abstract: In today's society, along with the social specialized division being increasingly profound and complex, greater demand for team and corresponding team spirit is put forward. Based on the Network Comprehensive Practice Curriculum Reform Project, this paper provides an analysis and induction of the procedure for cultivating student team and team spirit to develop a characteristic team and team spirit.

Abstract: With the mature development of trunk roads and national highways, China diverts her attention to rural highways' development in the face of issues concerning agriculture, rural areas and farmers. Rural highways make great contribution to the development of rural economy and will resolve issues adequately. So rural highway should receive close attention. But there is no answer from experience in maintenance field, the maintenance mechanism is unscientific, and its management is confused. If we can't change this situation properly, it will largely affect the maintenance quality of rural highway and be an obstacle to the travel of farmers and the circulation of agricultural goods. So we take Wuhan rural highway for example to settle the potential problems. In order to get the experience and revelation, first, I make it clear about the concept of rural highway and analyze the maintenance situations of Wuhan, the capital of Hubei province in China; Second, I’d like to point out the problems in the maintenance mechanism of Wuhan rural highway; Then, I give countmeasures to maintenance mechanism of Wuhan rural highway from the financing channels and maintenance model. The financing channels to get adequate funds and maintenance model fully exerting its economic factions will directly affect the quality of rural highway and even the development of national economy. The abundant fluent funds supply chains and the optimization of maintenance model are the guarantee of safety and efficiency of rural highway, directly affect the trips of farmers and the circulation of agricultural goods, promote the development of integration of urban and rural economies and help construct a harmonious society.

Abstract: A dual field of view and zoom infrared optical system with uncooled infrared staring focal plane arrays is designed in this paper. The operating waveband of the system is 8～12μm, and zoom radio is 3×. The optical configuration is based on the axial motion of a lens group along the optical axis. Optical material used infrared monocrystalline silicon、Znse, In order to achieve high performance、high image quality, used two even aspheric surfaces in this system. The advantages of this system are the high imaging quality、small volume、light weight.

Abstract: Virtual Reality technology is a hot research field in simulation of complex electromagnetic and its practical environment in the condition of information and high technology war. The paper discussed the main framework of spatial electromagnetic environment computing and simulating, presented realizing method and key arithmetic designing based on Virtual Reality Modeling Language. The work is evidently valuable for quantitative examinations, evaluation, and analysis of complex electromagnetic environment function, diversification, and effect on human beings, electronic units.

Abstract: This paper studies a method based on synchronized prefix improved method, use a synchronous frequency method related to the system time (TOD) to generate the synchronization frequency, each synchronous frequency changes over time in constantly changing, thus protecting synchronous frequency, and sent low frequency TOD Is calculated out of the high TOD, which increases the difficulty of deciphering. the results of Performance Analysis show that TOD self-synchronizing synchronizing time is quick, the synchronized probability is big, good randomness, has met the project design anticipated requirements.

Abstract: The Kurshio can affect sonar detection notably. The software named Gis ArcView is used to identify the Kuroshio area by analyzing underwater acoustics data. And seawater temperature isolines are drawn based on the temperature data which are distributed at some intervals in terms of latitude and longitude. The box counting method is applied to calculating the fractal dimension of the Kuroshio seawater temperature isolines in different seasons at the depth of 60m and 150m.The results indicate that the fractal dimension at 150m deep is bigger than that at 60m, but the former fluctuates less than the latter.It is conformed to the facts about the Kuroshio. Acoustic wave is the best medium through which acoustic information can be well transmitted. In the Kurshio area where underwater acoustic environment is rather complex, many singular areas are formed in the three-dimension sound field, in which sonar detection and tracking will be affected to a great extent. However, with the development of remote sensing technologies, it is possible to observe and forecast such mid-scale phenomena as the Kurshio, ocean fronts and interwaves. Therefore, how to effectively extract and analyze the main characters of these phenomena is quite important for Navies. Some people still get used to judging Kurshio’s existence and even intensity as well by simple criteria for a long time. For example, when the exchange of seawater temperature is exceeds 0.1°C/n mile, it will be considered that an ocean front exists. This criterion in fact is so ambiguous not only in this regard, but also in describing the Kurshio’s intensity[1]. In vies of this, the author operates the software, GIS ArcView, to extract and analyze the Kurshio, and take the box counting method[2] to calculate out the fractal dimensions in the area between 20º~30º N and 120 º~130ºE respectively at the depths of 60m and 150m.

Abstract: Through the characteristics of the Impulse electro flotation Wastewater treatment equipment, the factors which affect the efficiency of this technology are analyzed. According to the Kinematical theory of flocculation process, the free particle flotation removal model is established used in the way how the steel ball model is simplified. , and the variable process of the concentration of the free particle along with the time is stimulated to be obtained. This mathematical model has the theoretical reason of how to choose the electric flotation parameters and design of the electric flotation treatment equipments. The result proves that when the treatment time is between 20 to 25 min., the removal rate of the free particles will achieve to above 90%, which is similar to the experiment data.