水声环境特征参数并行预报方法研究

随着水声装备的快速发展,其性能发挥与海洋环境的耦合越来越紧密,如何为水声传感器提供长时间、大范围、精细化水声环境参数信息,对优化水声传感器设计,充分发挥其探测性能,实现海洋环境与传感器性能发挥的最佳匹配具有重要意义。利用MPI并行编程环境开发了水声环境特征参数并行预报程序,实现了水声环境特征参数的快速预报,针对并行程序存在的任务负载不均衡问题,分析了造成负载分配不均衡的原因,给出了性能优化的策略和方法。测试结果表明,优化后的并行程序,负载均衡问题得到了有效改善,计算时间大幅缩短,大大提升了水声环境参数预报能力。     

面向软件定义网络的两级DDoS攻击检测与防御

分布式拒绝服务(DDoS)攻击一直是互联网的主要威胁之一,在软件定义网络(SDN)中会导致控制器资源耗尽,影响整个网络正常运行。针对SDN网络中的DDoS攻击问题,文章设计并实现了一种两级攻击检测与防御方法。基于控制器北向接口采集交换机流表数据并提取直接特征和派生特征,采用序贯概率比检验(Sequential Probability Ratio Test,SPRT)和轻量级梯度提升机(LightGBM)设计两级攻击检测算法,快速定位攻击端口和对攻击类型进行精准划分,通过下发流表规则对攻击流量进行实时过滤。实验结果表明,攻击检测模块能够快速定位攻击端口并对攻击类型进行精准划分,分类准确率达到98%,攻击防御模块能够在攻击发生后2 s内迅速下发防御规则,对攻击流量进行过滤,有效保护SDN网络的安全。     

基于CC标准的DBMS审计模块设计

采用基于标准的安全产品开发方法进行DBMS安全功能增强。首先分析了CC标准中对于审计的功能要求;然后根据数据库管理系统产品的特性提炼出审计方面必须具备的功能;最后给出了一种以特权调用为小心的数据库管理系统审计功能模块的实现方案。     

Mesh Denoising using Extended ROF Model with L1 Fidelity

This paper presents a variational algorithm for feature‐preserved mesh denoising. At the heart of the algorithm is a novel variational model composed of three components: fidelity, regularization and fairness, which are specifically designed to have their intuitive roles. In particular, the fidelity is formulated as an L₁ data term, which makes the regularization process be less dependent on the exact value of outliers and noise. The regularization is formulated as the total absolute edge‐lengthed supplementary angle of the dihedral angle, making the model capable of reconstructing meshes with sharp features. In addition, an augmented Lagrange method is provided to efficiently solve the proposed variational model. Compared to the prior art, the new algorithm has crucial advantages in handling large scale noise, noise along random directions, and different kinds of noise, including random impulsive noise, even in the presence of sharp features. Both visual and quantitative evaluation demonstrates the superiority of the new algorithm.     

目标与机会平衡规划法

提出一种目标与机会平衡规划法．基于待决策问题的有效决策前沿曲线形状的全局信息,通过权衡决策目标收益和实现机会两个因素的数值关系以及二者沿有效决策前沿曲线变化速度的对比关系,最大限度地提高决策效用．该方法能以更合理、更全面、更灵活的方式分析处理随机优化问题,有效解决期望值模型、机会约束规划法和相关机会规划法之间的矛盾．最后通过算例表明了所提出方法的主要特点和有效性．     

改进的模糊Q学习方法及其在RoboCup中的应用

为了在multi-agent系统中实现agent之间的竞争与协作,该文提出了一种新的在线学习方法,即：改进的模糊Q学习方法,在这种方法中,agent通过增强学习方法来调节模糊推理系统,进而获得最优的模糊规则。为了改善学习的时间,Q学习方法中的奖励值并不是固定的,而是根据状态而变化。将改进的模糊Q学习方法应用到RoboCup仿真环境中,使智能体通过在线学习获得跑位技巧。并通过实验证明厂该方法的有效性。     

基于可信平台模块的NSPK协议

本文针对Needham-Schroeder公钥认证协议存在的问题,利用TPM的相关功能对协议进行了改进,提出了基于TPM的NSPK认证协议。解决了攻击者仿冒实体A与实体B共享秘密数据的安全缺陷,使其安全性有了显著提高。     

基于网络模型的组件化软件开发方法研究

文章将网络技术溶入到组件化技术当中,针对已有组件化技术所存在的隐式指定组件连接关系的问题,提出了一种"基于网络模型"的组件化设计方法,并从组件的模型、组件报文处理机制、软件架构、组件的使用以及相应的应用实例等方面对该设计方法进行阐述;该方法为组件的连接提供了一种灵活的调整机制,并使组件具有更强的独立性和封装性;在设计与实现"网络实验室管理系统"的实际应用中,大大提高了软件质量,缩短了开发时间。     

Using computational intelligence for large scale air route networks design

Due to the rapid development of air transportation, Air Route Networks (ARNs) need to be carefully designed to improve both efficiency and safety of air traffic service. The Crossing Waypoints Location Problem (CWLP) plays a crucial role in the design of an ARN. This paper investigates this problem in the context of designing the national ARN of China. Instead of adopting the single-objective formulation established in previous research, we propose to formulate CWLP as a bi-objective optimization problem. An algorithm named Memetic Algorithm with Pull–Push operator (MAPP) is proposed to tackle it. MAPP employs the Pull–Push operator, which is specifically designed for CWLP, for local search and the Comprehensive Learning Particle Swarm Optimizer for global search. Empirical studies using real data of the current national ARN of China showed that MAPP outperformed an existing approach to CWLP as well as three well-known Multi-Objective Evolutionary Algorithms (MOEAs). Moreover, MAPP not only managed to reduce the cost of the current ARN, but also improved the airspace safety. Hence, it has been implemented as a module in the software that is currently used for ARN planning in China. The data used in our experimental studies have been made available online and can be used as a benchmark problem for research on both ARN design and evolutionary multi-objective optimization.     

微机控制太阳能逆变电源

介绍了一种微机控制太阳能逆变电源,在这里微计算机按照给定的功率来控制逆变电源的输出电流,由于采用了锁相环技术,保证了逆变电源的输出与电网电压严格同步。控制器选用 Ｉｎｔｅｌ ８９Ｃ５１单片机,并在实验室中进行了实验,实验结果证明理论分析是正确的。