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New Near Space Security Handoff Scheme Based on Context Transfer
一种新的基于上下文传递的临近空间安全切换机制
XU Guo-yu,CHEN Xing-yuan,DU Xue-hui,<br>徐国愚,陈性元,杜学绘
计算机科学 , 2013,

Abstract: 针对临近空间中安全切换问题,提出一种新的基于上下文传递的安全切换机制。首先,设计了一种面向临近空间浮空器的切换基站预测算法,以基于多普勒频移技术计算飞行器发生切换的时间与位置,确定切换基站；其次,利用上下文传递机制预先将认证信息发送给切换基站,保证切换过程中通信的可靠性。性能分析与仿真实验表明,该机制通信与计算开销小,强制中断概率低,能够满足临近空间的应用需求。

Abstract: A coupled model of finite element method with linear programming was used for the management of karst-fracture water resource in Linzi District of Zibo Municipality, Shandong Province. The mathematical model is given by where H is the groundwater head, Tx and Ty are the components of transmissivity tensor. W is the replenishment in the vertical direction. ST is the storativity, Qij is the pumping rate in well j at time level i. D is the flow domain. T1 is the first kind of boundary, T21 is the impermeable boundary, T22 is the described flux boundary. H0 and f are the described heads and q is the described flux. The model can be decomposed into 2 models and approached by finite element method.The optimal management model is as follows :Objective function:Subject towhere Q(j,1) is the pumping rate in well j at time step l. a (i. j. k-l+ 1) is the influence coefficient,s (i. k) is the constraint of drawdown in well i at time step k and s1 (i, k) is the additional drawdown. a(i. j, k- l + 1) and s1 (i, k) can be computed by finite element method. The optimization model has been solved by simplex method. The results are shown in this article.

Abstract: In this paper, we discuss the similarity of all the levels of CIPS. Every level has three elements: the information, the control and the object, which can be considered as the elements of a control system. Based on this, we present an extension control model of function integration in CIPS.

Abstract: Based on analytical results on hydrogeological feature and the situation of groundwater contamination, several mathematic methods were adopted to evaluate fracture-karst water quality and to simulate the distribution of contaminants in the groundwater.A fuzzy mathematical method,was applied to evaluate fracture-karst water quality in Boshan City. Geostatistical methods including Kriging analysis and trend analysis,were employed to simulate contaminants distribution in aquifer.Grey system method was adopted to forecast SO42-concentrations in representative wells. Characteristic finite element solution of adjective-dispersive equation was used for modeling contaminants distribution in groundwater and predicting groundwater contamination in the future The characteristics and applicable condition of each mathematic method are discussed as well.

Abstract: This paper reviews based on available scientific knowledge the importance of soil fauna for N cycling and its response to N deposition. The functioning of terrestrial ecosystems depend highly on soil fauna biodiversity, which have characteristic impacts on ecosystem processes. N is usually a limited nutrient element for plant growth, and is also the quantitatively most important mineral element absorbed by plants from the soil. But the supply of N by turnover in the ecosystem fully depends on biological soil processes. The diversity of soil fauna is large and has important impact on this N turnover. It is suggested that 30 percent of N mineralization is due to the action of soil fauna, and the percentage is even higher under the action of macrofauna. Many soil fauna, such as earthworm, termite and enchytraeid can accelerate N mineralization rate significantly. The diversity of functional groups is important in the research of the effect of soil fauna community on N mineralization, but taxonomic diversity's effects are not significant. It is also recovered that soil fauna can enhance the efficiency of N absorption by plants, however, the mechanism of which is not known yet. N deposition is a serious environment problem globally. It changes soil physical and chemical characteristics, the quality of food, the mutual role of community, and even kill soil life forms directly. As a result, the diversity of soil fauna and its function in the ecosystem is affected by N deposition. The research methods used in studying soil fauna and N turnover, the impact and its mechanism of soil fauna on N turnover, and the responses of soil fauna to N deposition is discussed in this paper. The demands for soil fauna research in the tropic of N turnover and impact N deposition is outlined. .

Abstract: In triangulated surface meshes, there are often very noticeable size variances (the vertices are distributed unevenly). The presented noise of such surface meshes is therefore composite of vast frequencies. In this paper, we introduce an adaptor in the diffusion partial differential equation for noise removal of arbitrary triangular manifolds. The proposed approach is simple and is easy to incorporate into any diffusion implementation with significant improvements over evolution results with identity adaptor.

Abstract: This paper analyzes the photodynamic damage of bR by HPD using resonance Raman Spectroscopy as probe. On the basis of the observed damage phenomenon, we investigated the damage region of bR and fundamentally confirmed that the C-C and C=C bond of retinene in chromophore are the loci easy to be damaged.

Abstract: ZnO nanocrystalline sensitive materials of doped Sb3+ were prepared by citrate method. The effect of doped Sb3+ on construction and dielectric property of ZnO nanocrystalline were studied. The most favourable experiment condition for the preparation of ZnO nanocrystalline of doped Sb3+ were studied. XRD, IR, TG, DTA and TEM examinations were used to characterize the samples.It is observed that Sb3+ content is increased, and lattice constant and volume conductance of ZnO nanocrystalline are changed.

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低压硅外延生长的热力学研究
徐宝琨,赵慕愚
半导体学报 , 1982,

Abstract: 本文对SiCl_4氢还原的复杂化学反应体系的平衡状态作了计算.给出体系在低压(P=0.1大气压、P=0.01大气压)和常压(P=1大气压),温度T从900K至1500K,及不同初始成分条件下的平衡成分图、产率图、外延生长控制参数的阈值图,并提出了有关改进低压硅外延工艺的参考性意见.

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