摘要：Efficiency and scalability are still the bottleneck for secure multi-party computation geometry （SMCG）. In this work a secure planar convex hull （SPCH） protocol for large-scaled point sets in semi-honest model has been proposed efficiently to solve the above problems. Firstly, a novel priva- cy-preserving point-inclusion （PPPI） protocol is designed based on the classic homomorphic encryp- tion and secure cross product protocol, and it is demonstrated that the complexity of PPPI protocol is independent of the vertex size of the input convex hull. And then on the basis of the novel PPPI pro- tocol, an effective SPCH protocol is presented. Analysis shows that this SPCH protocol has a good performance for large-scaled point sets compared with previous solutions. Moreover, analysis finds that the complexity of our SPCH protocol relies on the size of the points on the outermost layer of the input point sets only.

摘要：information analysis of high dimensional data was carried out through similarity measure application. High dimensional data were considered as the a typical structure. Additionally, overlapped and non-overlapped data were introduced, and similarity measure analysis was also illustrated and compared with conventional similarity measure. As a result, overlapped data comparison was possible to present similarity with conventional similarity measure. Non-overlapped data similarity analysis provided the clue to solve the similarity of high dimensional data. Considering high dimensional data analysis was designed with consideration of neighborhoods information. Conservative and strict solutions were proposed. Proposed similarity measure was applied to express financial fraud among multi dimensional datasets. In illustrative example, financial fraud similarity with respect to age, gender, qualification and job was presented. And with the proposed similarity measure, high dimensional personal data were calculated to evaluate how similar to the financial fraud. Calculation results show that the actual fraud has rather high similarity measure compared to the average, from minimal 0.0609 to maximal 0.1667.

摘要：Aspect-oriented modeling can uncover potential design faults, yet most existing work fails to achieve both separation and composition in a natural and succinct way. This study presents an aspect-oriented modeling and analysis approach with hierarchical Coloured Petri Nets(HCPN). HCPN has sub-models and well-defined semantics combining a set of submodels. These two characteristics of HCPN are nicely integrated into aspect oriented modeling. Submodels are used to model aspects while the combination mechanism contributes to aspects weaving. Furthermore, the woven aspect oriented HCPN model can be simulated and analyzed by the CPN Tools. A systematic web application case study is conducted. The results show the system original properties are satisfied after weaving aspects and all design flaws are revealed. As such, the approach can support web application design and analysis in an aspect-oriented fashion concisely and effectively.

摘要：我们设计了一种不含金属的二维双层异质结构BC_(4)N/aza-CMP,该体系可在水溶液中将N2分子通过光催化作用还原为氨.通过密度泛函理论和非绝热分子动力学方法,我们发现该异质结构中的光生载流子遵循直接Z型迁移机制.这将有效分离光生电荷并使氮还原反应和氧发生反应分别在BC_(4)N层和aza-CMP层上进行,实现反应位点的空间分离.值得一提的是,BC_(4)N上的B原子可以有效吸附N2分子并激活N≡N键,这将降低氮还原反应的过电势并促进随后的质子化进程,且该异质双层具有适宜的带隙和带边位置,能够有效吸收太阳光并提供充足的驱动力来触发氧化还原反应,实现无任何牺牲剂辅助的光催化氨合成.本工作将为直接Z型固氮光催化剂的设计提供重要借鉴,并促进太阳能驱动的氨合成的发展.

摘要：In this paper, we rewrote the equation of algebraic curve segmentswith the geometric informationonboth ends. The optimal or nearly optimal rationalparametric equation is determinedbythe principle that parametricspeedsat both endsareequal. Comparing withotherliteratures, the methodofthis paper has advantage in efficiency andiseasy to realize. The equation of optimal rational parameterization can be obtained directly by the information of both ends. Large numbers ofexperimental data show that our method hasbeen given withmore self-adaptability and accuracy than that ofotherliteratures, and if the parametricspeedat any end reaches its maximum or minimum value, the parameterization is optimal; otherwise itis close tooptimal rational parameterization.

摘要：Optimal parameterization of specified segment on the algebraic curves is a hot issue in CAGD and CG. Take the optimal approximation of arc-length parameterization as the criterion of optimal parameterization, and the optimal or close to optimal rational parameterization formula of any specified segment on the conic curves is obtained. The new method proposed in this paper has ad- vantage in quantity of calculation and has strong self-adaptability. Finally, a experimental comparison of the results obtained by this method and by the traditional parametric algorithm is conducted.

摘要：人工智能(artificial intelligence, AI)技术的发展为源码处理场景下AI系统提供了强有力的支撑.相较于自然语言处理,源码在语义空间上具有特殊性,源码处理相关的机器学习任务通常采用抽象语法树、数据依赖图、控制流图等方式获取代码的结构化信息并进行特征抽取.现有研究通过对源码结构的深入分析以及对分类器的灵活应用已经能够在实验场景下获得优秀的结果.然而,对于源码结构更为复杂的真实应用场景,多数源码处理相关的AI系统出现性能滑坡,难以在工业界落地,这引发了从业者对于AI系统鲁棒性的思考.由于基于AI技术开发的系统普遍是数据驱动的黑盒系统,直接衡量该类软件系统的鲁棒性存在困难.随着对抗攻击技术的兴起,在自然语言处理领域已有学者针对不同任务设计对抗攻击来验证模型的鲁棒性并进行大规模的实证研究.为了解决源码处理场景下AI系统在复杂代码场景下的不稳定性问题,提出一种鲁棒性验证方法 (robustness verification by Metropolis-Hastings attack method, RVMHM),首先使用基于抽象语法树的代码预处理工具提取模型的变量池,然后利用MHM源码攻击算法替换变量扰动模型的预测效果.通过干扰数据和模型交互过程,观察攻击前后的鲁棒性验证指标的变化量来衡量AI系统的鲁棒性.以漏洞预测作为基于源码处理的二分类典型场景为例,通过在3个开源项目的数据集上验证12组AI漏洞预测模型鲁棒性说明RVMHM方法针对源码处理场景下AI系统进行鲁棒性验证的有效性.

摘要：In this study, a novel hybrid intelligent mining system integrating rough sets theory and support vector machines is developed to extract efficiently association rules from original information table for credit risk evaluation and analysis. In the proposed hybrid intelligent system, support vector machines are used as a tool to extract typical features and filter its noise, which are different from the previous studies where rough sets were only used as a preprocessor for support vector machines. Such an approach could reduce the information table and generate the final knowledge from the reduced information table by rough sets. Therefore, the proposed hybrid intelligent system overcomes the difficulty of extracting rules from a trained support vector machine classifier and possesses the robustness which is lacking for rough-set-based approaches. In addition, the effectiveness of the proposed hybrid intelligent system is illustrated with two real-world credit datasets.

摘要：Future climate change is usually projected by coupled earth system models under specific emission sce- narios designed by integrated assessment models （IAMs）, and this offline approach means there is no interaction between the coupled earth system models and the IAMs. This paper introduces a new method to design possible future emission scenarios and corresponding climate change, in which a simple economic and climate damage component is added to the coupled earth system model of Beijing Normal University （BNU-ESM）. With the growth of population and technological expertise and the declining emission-to-output ratio described in the Dynamic Inte- grated Climate-Economy model, the projected carbon emission is 13.7 Gt C, resulting in a 2.4℃ warming by the end of the twenty-first century （2080-2099） compared with 1980-1999. This paper also suggests the importance of the land and ocean carbon cycle in determining the CO2 con- centration in the atmosphere. It is hoped that in the near future the next generation of coupled earth system models that include both the natural system and the social dimension will be developed.

摘要：Two-dimensional(2 D)van der Waals materials have been widely adopted as photocatalysts for water splitting,but the energy conversion efficiency remains *** the basis of first-principles calculations,we demonstrate that the 2 D Janus group-Ⅲchalcogenide multilayers:In Ga XY,M2XY and In GaX2(M=In/Ga;X,Y=S/Se/Te),are promising photocatalysts for highly-efficient overall water *** intrinsic electric field enhances the spatial separations of photogenerated carriers and alters the band alignment,which is more pronounced compared with the Janus *** solar-to-hydrogen(STH)efficiency with the upper limit of 38.5%was predicted in the Janus *** excitingly,the Ga vacancy of In Ga SSe bilayer effectively lowers the overpotentials of hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)to the levels provided solely by the photogenerated *** theoretical results suggest that the 2 D Janus group-III chalcogenide multilayers could be utilized as highly efficient photocatalysts for overall water splitting without the needs of sacrificial reagents.