负面在线评论及商家回复对顾客购买意愿的影响

从负面在线评论比例和失误严重性两个角度出发，通过引入归因理论、感知信任和商家回复等相关内容，探究负面在线评论对潜在顾客购买意愿影响机制和内部机理。对496份调查问卷所得数据进行统计分析，研究结果表明：负面在线评论比例和失误严重性都对潜在顾客购买意愿有显著的负向影响，且两者都通过影响失误的归属性归因、可控性归因、稳定性归因和感知信任影响潜在顾客购买意愿；在负面在线评论比例与失误严重性不同的情况下，商家应采取不同的回复策略实现节约成本与减小损失的目的。     

砂岩在西湖凹陷花港组交互式盖层中的作用初探

西湖凹陷花港组盖层具有砂泥岩交互式发育特征，而与泥岩伴生的砂岩类盖层的油气封闭作用研究较少。采用岩芯、镜下观察及压汞等分析方法，对砂泥岩交互式盖层中的砂岩特征进行了分析。结果表明，盖层中的砂岩可作为有效盖层，砂岩类盖层早期受沉积环境控制，含有较多的泥质而导致早期压实作用较强，加之晚期的黏土矿物转换及胶结物的发育，具备形成良好盖层的条件。在不同地区进行砂岩盖层有效性研究时应以沉积环境为基础，针对不同类型的砂岩进行成岩作用研究，并针对不同类型的砂岩样品进行实验分析以明确砂岩盖层的有效性。     

ID-Based Public Auditing Protocol for Cloud Storage Data Integrity Checking with Strengthened Authentication and Security

Cloud storage service reduces the burden of data users by storing users’ data files in the cloud. But, the files might be modified in the cloud. So, data users hope to check data files integrity periodically. In a public auditing protocol, there is a trusted auditor who has certain ability to help users to check the integrity of data files. With the advantages of no public key management and verification, researchers focus on public auditing protocol in ID-based cryptography recently. However, some existing protocols are vulnerable to forgery attack. In this paper, based on ID-based signature technology, by strengthening information authentication and the computing power of the auditor, we propose an ID-based public auditing protocol for cloud data integrity checking. We also prove that the proposed protocol is secure in the random oracle model under the assumption that the Diffie-Hellman problem is hard. Furthermore, we compare the proposed protocol with other two ID-based auditing protocols in security features, communication efficiency and computation cost. The comparisons show that the proposed protocol satisfies more security features with lower computation cost.     

Superior corrosion resistance-dependent laser energy density in(CoCrFeNi)95Nb5 high entropy alloy coating fabricated by laser cladding

(CoCrFeNi)95Nb5 high entropy alloy(HEA)coatings were successfully fabricated on a substrate of Q235 steel by laser cladding technology.These(CoCrFeNi)95Nb5 HEA coatings possess excellent properties,particularly corrosion resistance,which is clearly superior to that of some typical bulk HEA and common engineering alloys.In order to obtain appropriate laser cladding preparation process parameters,the effects of laser energy density on the microstructure,microhardness,and corrosion resistance of(CoCrFeNi)95Nb5 HEA coating were closely studied.Results showed that as the laser energy density increases,precipitation of the Laves phase in(CoCrFeNi)95Nb5 HEA coating gradually decreases,and diffusion of the Fe element in the substrate intensifies,affecting the integrity of the(CoCrFeNi)95Nb5 HEA.This decreases the microhardness of(CoCrFeNi)95Nb5 HEA coatings.Moreover,the relative content of Cr2O3,Cr(OH)3,and Nb2O5 in the surface passive film of the coating decreases with increasing energy density,causing corrosion resistance to decrease.This study demonstrates the controllability of a high-performance HEA coating using laser cladding technology,which has significance for the laser cladding preparation of other CoCrFeNi-system HEA coatings.     

基于共价有机框架的仿生光动力学治疗试剂的构建

共价有机框架（COF）是一类新兴的多孔有机聚合物，因其具有较大的比表面积、有序的孔道结构以及良好的生物相容性，已成为具有潜力的纳米药物载体.制备了基于COF纳米颗粒的仿生纳米复合物，负载光敏剂孟加拉玫瑰红（RB），并包裹癌细胞膜（CMV）对该复合物进行仿生修饰.结果表明：制备的COF/RB@CMV纳米复合物具有良好的生物兼容性，能够被肿瘤细胞有效摄取，并在光照激活条件下产生对细胞具有高毒性的活性氧化物（ROS），进而起到了杀伤肿瘤细胞的作用.提出了一种新的基于COF的仿生纳米平台用作光动力学治疗（PDT）试剂.     

融合码盘和激光雷达的里程计与建图

提出了一种用于自动驾驶汽车的低漂移、低延迟的里程计与高精度建图的算法。该方法融合了多种传感器的测量结果，包括车轮编码器、转向盘转角编码器、激光雷达及可选GPS等的测量结果。里程计算法由车轮里程计和激光里程计组成：前者基于车辆运动学模型，高频、实时估计位姿增量，用于点云去畸变和为后者优化位姿提供可用的初值；后者以较低的频率估计车辆的精确位姿变化，以补偿前者累计的误差，其核心是一种基于角度度量的两阶段特征提取方法。建图算法基于因子图，包含激光里程计因子、回环因子和可选GPS因子，通过增量平滑和建图算法优化全局轨迹，在线生成全局地图，其中GPS因子能够自动对齐GPS坐标系和里程计坐标系，逐步融合GPS测量值，解除了算法初始化过程对于GPS的依赖。所提出的方法在自动驾驶汽车平台数据集上进行了评估，并和已开源的部分相关工作进行对比，结果表明它具有更低的漂移率，在本文进行的最大规模的测试中达到了0.53%。相关代码以开源形式供交流参考（https：//github.com/Saki-Chen/W-LOAM）。     

在组织中实践基于模型的系统工程

 基于模型的系统工程（MBSE）要解决复杂系统工程的问题，需要通过信息、计算和软件来架设传统系统与各领域工程（嵌入式、安全、结构等）之间的桥梁。综合产品团队使MBSE的有效方式可以有效降低实践风险，同时MBSE工具链和集成开发环境的成熟度也是制约实践效果的重要影响因素。全面数字化趋势引领的第4次工业革命中，MBSE向数据主线/数字工程等演进的趋势日趋显著。面向未来，必须认识到MBSE和产品数据管理/产品生命周期管理集成，以及在数字工程和数字主线大背景下理解和再造MBSE的必要性。