初道屏蔽效应对低能电子碰撞H(e,2e)反应的影响

考虑初道屏蔽效应,研究了低能电子碰撞H(e,2e)的反应过程.计算了共面非对称几何条件下能量为27.2 eV的入射电子碰撞H(e,2e)反应的三重微分截面(TDCS),将其计算结果与3C、DS3C和CDS3C模型所得结果及实验数据进行了比较,结果表明CDS3C模型能对上述碰撞过程成功描述,改善了与实验结果的符合程度.     

产生式与判别式分类方法比较研究

分类是数据挖掘领域研究的热点,产生式与判别式是数据挖掘中两种不同的分类模型。产生式模型具有通用性、灵活性及清晰的分层结构,学习得到的模型很容易满足模型解释要求;判别式模型没有明显的对系统中变量的基本分布建模的企图,仅仅对输入到输出之间映射的最优化感兴趣,可以提供更好的分类性能。从准确率、建模时间及渐进误差等方面对产生式与判别式分类方法进行了分析与比较,为研究人员在分类模型的选择上提供了参考。     

Self-alignment of full skewed RSINS：observability analysis and full-observable Kalman filter

Traditional orthogonal strapdown inertial navigation sys-tem （SINS） cannot achieve satisfactory self-alignment accuracy in the stationary base： taking more than 5 minutes and al the iner-tial sensors biases cannot get ful observability except the up-axis accelerometer. However, the ful skewed redundant SINS （RSINS） can not only enhance the reliability of the system, but also improve the accuracy of the system, such as the initial alignment. Firstly, the observability of the system state includes attitude errors and al the inertial sensors biases are analyzed with the global perspective method： any three gyroscopes and three accelerometers can be assembled into an independent subordinate SINS （sub-SINS）;the system state can be uniquely confirmed by the coupling connec-tions of al the sub-SINSs;the attitude errors and random constant biases of al the inertial sensors are observable. However, the ran-dom noises of the inertial sensors are not taken into account in the above analyzing process. Secondly, the ful-observable Kalman filter which can be applied to the actual RSINS containing random noises is established; the system state includes the position, ve-locity, attitude errors of al the sub-SINSs and the random constant biases of the redundant inertial sensors. At last, the initial self-alignment process of a typical four-redundancy ful skewed RSINS is simulated： the horizontal attitudes （pitch, rol ） errors and yaw error can be exactly evaluated within 80 s and 100 s respectively, while the random constant biases of gyroscopes and accelero-meters can be precisely evaluated within 120 s. For the ful skewed RSINS, the self-alignment accuracy is greatly improved, mean-while the self-alignment time is widely shortened.     

基于软件库的软件生产线模型研究

为降低软件生产线初期投入高\, 风险大的问题, 提出基于软件库的软件生产线过程模型及无缝迁移模型。基于生产线过程模型建立了车载多媒体模拟系统以及相关支持工具, 依托关系数据库强大的存储与检索功能。采用这两个模型能降低采用生产线技术的初期投入成本, 并有助于生产线的迁移, 具有一定的实用价值及推广价值。     

我国国有商业银行表外业务存在问题及解决对策

该文通过阐述我国国有商业银行表外业务发展中的情况和特点,根据其出现的品种单一、业务量少、区域发展不均衡和管理不规范等问题,相应地提出了加快金融创新、提高对其业务重要性的认识和业务营销水平、加强银行间区域合作和完善相关规章制度建设等合理的对策,以期能对我国金融业的发展提供些许有益的参考。     

论带“五等”字号的虚封爵——晋宋之际国家官爵制度上的变化之一

晋宋之际，国家官爵制度上发生的重要变化之一就是带“五等”字号虚封爵的出现。晋末特殊军事政治形势之下，京口北府集团凭借强势军功击败高门士族，取得压倒性的军事政治优势，京口北府军功受益阶层由此形成。带“五等”字号虚封爵适时地出现则成为这个现实政治变化的典型表现之一。笔者从这种虚封爵产生的时间和目的进行详细分析，以为正是出于酬赏义熙初年京口北府集团建义之功，朝廷才创设了这种虚封爵。这种虚封爵突破既有的门阀制度优势，确立了以军功为核心的分享军事政治利益的价值导向。这使得京口北府集团凭借军功所获取的军事政治利益不仅在制度层面上得到保障，而且在价值层面上取得其正当性和合法性，也就在这个时候，京口北府军功利益阶层得以成立。酬赏军功的这一目的也直接决定了虚封爵的若干特点，对此，笔者也予以分析说明。     

音幻小屋体验对学龄儿童黑暗焦虑的影响

目的：评价音幻小屋体验对学龄儿童黑暗焦虑的影响。方法：参加音幻小屋体验学龄（7-13岁）儿童78例,用焦虑自评量表（SAS）分别测定音幻小屋体验前及体验后1周,1月对黑暗刺激焦虑评分。结果：体验后1周,1月对黑暗刺激焦虑评分均高于体验前（p〈0.01）,且两者无差异（p〉0.05）。结论：学龄儿童应远离恐怖刺激,避免心理创伤。     

GPSNISNAV integrated relative navigation and attitude determination system for ultra-close spacecraft formation flying

For the improvement of accuracy and better fault-tolerant performance, a global position system (GPS)/vision navigation (VISNAV) integrated relative navigation and attitude determination approach is presented for ultra-close spacecraft formation flying. Onboard GPS and VISNAV system are adopted and a federal Kalman filter architecture is used for the total navigation system design. Simulation results indicate that the integrated system can provide a total improvement of relative navigation and attitude estimation performance in accuracy and fault-tolerance.     

Atomic layer deposition on Pd nanocrystals for forming Pd-TiO2 interface toward enhanced CO oxidation

Pd typically exhibits relatively low catalytic activity in CO oxidation, as CO is apt to be adsorbed on Pd to poison the surface for O2 activation. In this Letter, we report that this limitation can be overcome by integrating Pd with TiO2. The TiO2 was coated on Pd nanocubes with a controllable thickness using atomic layer deposition (ALD) method. Given the different work functions of TiO2 and Pd, the electrons in TiO2 semiconductor will flow toward Pd. With the electron density increased on Pd, the adsorption of CO to Pd will be weakened while the oxygen activation can be facilitated. Meanwhile, the interface-confined sites at Pd-TiO2 may further enhance the oxygen activation. As the species adsorption and activation are strongly correlated with electron density, the performance of Pd-TiO2 in CO oxidation turns out to depend on the TiO2 thickness, which determines the number of transferred electrons, within a certain range (<1.8 nm). This work provides a new strategy for enhancing catalytic performance through tailoring charge densities in hybrid catalysts.     

江西兰科一新记录种—线柱兰

报道了产于南昌的兰科Orchidaceae线柱兰属Zeuxine线柱兰Z.strateumatica（L.）Schltr.,该种及其所在属均为江西首次发现。