A New Method for the Detections of Multiple Faults Using Binary Decision Diagrams

With the complexity of integrated circuits is continually increasing, a local defect in circuits may cause multiple faults. The behavior of a digital circuit with a multiple fault may significantly differ from that of a single fault. A new method for the detection of multiple faults in digital circuits is presented in this paper, the method is based on binary decision diagram （BDD）. First of all, the BDDs for the normal circuit and faulty circuit are built respectively. Secondly, a test BDD is obtained by the XOR operation of the BDDs corresponds to normal circuit and faulty circuit. In the test BDD, each input assignment that leads to the leaf node labeled 1 is a test vector of multiple faults. Therefore, the test set of multiple faults is generated by searching for the type of input assignments in the test BDD. Experimental results on some digital circuits show the feasibility of the approach presented in this paper.     

基于视线跟踪技术的眼控鼠标

利用基于图像处理技术的视线方向识别、跟踪方法,通过近红外光线在眼睛角膜反射产生的光斑和瞳孔中心的位置关系来确定视线方向,推导出人眼在计算机屏幕上的注视点,进而实现人眼对鼠标的定位与操作,其在显示屏上定位精度可达到40×40像素.     

概念性水文模型参数自动优选方法的比较研究

介绍了3种参数自动优选方法：罗森布瑞克法（Rosenbrock）、单纯形法（Simplex）和基因法（Genetic）。应用4个流域的水文资料，以三水源新安江模型为例，分析了基因法参数L和IMAX对优选结果的影响；对这3种优化方法的收敛程度、参数初值的选定以及不同组合情况的优选结果进行了比较研究。结果表明，基因法参数取IMAX＝5000，L＝10时比较合理；3种优化方法各有优点，基因法不依赖于参数初值的选定，罗森布瑞克法收敛速度快，单纯形法精度较高，建议以基因法优选结果为初值，然后采用罗森布瑞克法，最后采用单纯形法，可以得到最佳的优选结果。     

Theoretical calculations on the atomic and electronic structure of β-SiC(110) surface

We present a theoretical calculation of the atomic and electronic structure of β-SiC and its non-polar (110) surface using the full potential linear augmented plane wave (FPLAPW) approach. The calculated lattice constant and bulk modulus of β-SiC crystal are in excellent agreement with experimental data. The atomic and electronic structure of β-SiC(110) surface has been calculated by employing the slab and supercell model. It is found that the surface is characterized by a top-layer bond-length-contracting rotation relaxation in which the Si-surface atom moves closer towards the substrate while the C-surface atom moves outward. This relaxation is analogous to that of Ⅲ-Ⅴ semiconductor surface. The driving mechanism for this atomic rearrangement is that the Si atom tends to a planar sp²-like bonding situation with its three N neighbors and the N atom tends to a p³-like bonding with its three Si neighbors. Furthermore, surface relaxation induces the change from metallic to semiconducting characterization.     

Simulation and evaluation of the quality and availability of typical GLI ocean image

ADEOS-II satellite will be launched in the near future. It collocates many remote sensing instruments in the same platform. Among them, Global Image (GLI) is considered to be a main sensor which will play a key role. In order to understand the characteristics of future GLI ocean color images, a simulation and evaluation of the quality and availability of GLI typical ocean image has been done. In the paper, we first introduce the simulation models briefly, and simulate typical cases of radiance images at visible channels, in which the radiance distribution is based on geographic location, the satellite orbital parameters and sensor properties. A method, complex signal noise ratio (CSNR) to evaluate the image quality and availability, is developed according to the characteristics of image. Meanwhile, a series of CSNR images are generated from the simulated radiance components for different cases, which can be used to evaluate the quality and availability of GLI images before the ADEOS-II is placed in orbit. Finally, the quality and availability of GLI images are quantitatively analyzed by the simulated CSNR data. The results will be beneficial to the people who are in charge of GLI mission or plan to use the data from GLI.     

Construction of multivalent DNA vaccines forMycobacterium tuberculosis and its immunogenicity

The coding regions of Ag85B MPT-64, and ESAT-6 secreted proteins were cloned initially into the eukaryotic expression vector pJW4303, then transformed to E. coli Top 10 strain for plasmid DNA extraction and further analysis. Plasmids containing the right insertion were sequenced to confirm their identity. COS7 cells were transfected with a mixture containing serially diluted plasmid DNA encoding three secreted proteins and Lipofectin (Gibco). The supernatants and pellets prepared from various cell lines were run on SDS-PAGE gel and the expression of these proteins in COS7 cells were demonstrated by immunoblot using polyclonal or monoclonal antiserum of M.TBH37Rv. 21 days after first vaccination of C57BL-6 mice by all three recombinant eukaryotic expressing vectors, antibody titer for Ag85B reached 1∶3200. 21 days after second vaccination, the antibody titer reached 1∶102400. The highest antibody levels induced by multivalent vaccines after the second injection were equal to or even greater than the highest antibody levels of single DNA vaccine reported in literature after third injections. Antibody titer of MPT-64 was 1∶50 after the first injection and it reached 1∶200 after the second injection. No antigen-specific antibody against ESAT-6 was detected in sera harvested from immunized mice 21 days after both injections. Antigen-specific IFN-g level of Ag85B was 110 pg/mL while no antigen-specific IFN- g level of ESAT-6 and MPT-64 was detected even after third injections. To our knowledge, it is the first time that studies of polyvalent recombinant DNA vaccines against TB were carried out in C57BL-6 mice. Our results indicated that multiple DNA vaccines could be used to enhance protective responses against M.TB.     

铝合金LF6交流脉冲TIG焊的工艺研究

在LF6铝合金交流脉冲TIG焊过程中，焊接工艺参数（基值电流Ij、脉冲电流Im、脉冲频率fm、占空比K、气体流量Q）对焊缝成形及质量的影响进行试验。试验结果表明，交流脉冲TIG焊的去氧化膜，抗气孔能力及接头机械性能优于连续焊，该工艺已用于产品焊接上。     

以非晶态Ni-B合金阴极电解还原葡萄糖

实验采用化学镀镍法制备非晶态Ni-B合金电极，以此电极为阴极材料电解还原葡萄糖。结果表明非晶态Ni-B合金的电催化性能较晶态Ni优越，在温度为25℃，电流0．4A，电解90min，葡萄糖转化率达88．1％，电流效率保持87．5％。     

粗糙度和稳定度对绿洲生态系统能量平衡的影响

研究了粗糙度和稳定度等对绿洲生态系统能量平衡的影响。地表粗糙度和大气稳定度是控制地气间能量交换的重要因子，研究表明，绿洲中植被的温度不仅受反照率、空气温度影响而且受大气稳定性和地表粗糙度的影响，在其他条件相同的情况下，大气稳定度越高（低），植被的温度越高（低），地表粗糙度越小（大）植被的温度也越高（低）。研究还发现，绿洲中总的蒸散量的多平衡态特征只有在稳定度低的时候出现。在相同的气候条件下，低矮的植被在干旱半干旱地区更容易发展起来。另外研究了层结不稳定和层结稳定的情况下绿洲生态系统能量交换的差异。     

苏锡常地区地下水超采引发的环境地质问题及其对策

苏锡常地区长期以来由于过量开采地下水，引发了一系列的环境地质问题，不但造成了巨大的经济失损，而且影响一该地区的城市发展和投资环境，因此制定切实可行的措施，防止环境地质问题的发生和恶化对该地区的经济可持续发展具有十分重要的意义。