国防信息基础设施的建设与管理

讨论了国防信息基础设施的概念,分析了美军国防信息基础设施的发展状况、实施方法、主要途径,提出了发展我军信息基础设施的技术途径和措施建议.     

User location privacy protection mechanism for location-based services

With the rapid development of the Internet of Things (IoT), Location-Based Services (LBS) are becoming more and more popular. However, for the users being served, how to protect their location privacy has become a growing concern. This has led to great difficulty in establishing trust between the users and the service providers, hindering the development of LBS for more comprehensive functions. In this paper, we first establish a strong identity verification mechanism to ensure the authentication security of the system and then design a new location privacy protection mechanism based on the privacy proximity test problem. This mechanism not only guarantees the confidentiality of the user’s information during the subsequent information interaction and dynamic data transmission, but also meets the service provider’s requirements for related data.     

Accurate segmentation of land regions in historical cadastral maps

Historical cadastral maps are valuable sources for historians to study social and economic background of changes in land uses or ownerships. In order to conduct large-scale historical research, it is essential to digitize the cadastral maps. As being established in antiquity, however, they suffer from significant noise artifacts attributed to hand-drawn cartography. In this paper, we propose a novel method of extracting land regions automatically in historical cadastral maps. First, we remove grid reference lines based on the density of the black pixel with the help of the jittering. Then, we remove land owner labels by considering morphological and geometrical characteristics of thinned image. We subsequently reconstruct land boundaries. Finally, the land regions of a user’s interest are modeled by their polygonal approximations. Our segmentation results were compared with manually segmented results and showed that the proposed method extracted the land regions accurately for assisting cadastral mapping in historical research.     

Privacy from Promises to Protection

Privacy issues are becoming more and more important especially since the cyber and the real world are converging up to certain extent when using mobile devices. Means that really protect privacy are still missing. The problem is, as soon as a user provides data to a service provider the user looses control over her data. The simple solution is not to provide any data but then many useful services, e.g. navigation applications, cannot be used. In order to solve this problem, we propose privacy guaranteeing execution containers (PGEC). Basically the concept is that the application obtains access to the user data in a specially protected and certified environment, the PGEC. PGECs enable applications to access private user data and guarantee that the user data is deleted as soon as the service is quit. The PGEC also restricts the communication between the application and the service provider to what is explicitly allowed by the service user. In addition to those means the PGEC also implements countermeasures against malicious attacks such as modified host systems and covert channel attacks, which might be misusing CPU load to signal data out of the PGEC. Thus, the PGEC guarantees a “one time use” of the provided private data.     

标准与远程医疗服务

远程医疗服务为人们提供了远程获得优质医疗服务的可能性.但远程医疗服务系统本身是一个复杂的系统,提供远程医疗服务,需要患者医疗记录等的数字化和标准化以及医疗设施的互操作性,这对标准工作提出了一些新的需求.本文将重要介绍远程医疗服务的种类、远程医疗服务系统对标准的需求、以及相关标准化工作的进展.     

移动网络中数据业务关键性能指标KPI探讨

移动网络的性能评估是网络规划和优化建设的前提，数据业务的迅速发展为移动网络的性能评估提出新的课题，当前评价数据业务网络的关键性能指标主要有吞吐量、时延等，从网络的容量和质量角度出发提出每用户平均吞吐量和网络资源利用率两个关键性能指标，并分别进行理论分析，为数据业务网络的性能评估提供参考依据。     

Generation of grid multi-scroll chaotic attractors via switching piecewise linear controller

In this Letter, a novel method is developed for generating grid multi-scroll chaotic attractors using switching piecewise linear controller. First, a third-order linear system is designed to ensure that its unique equilibrium point belongs to a saddle-focus type with index 2 and the corresponding eigenvalues satisfy Shilnikov conditions. Then, by three different types of switching control strategies, the equilibrium point can be extended along both xy plane and z axis direction, so as to generate grid multi-scroll chaotic attractors. The dynamical behaviors are further analyzed. Moreover, an improved module-based circuit is designed for realizing 5×3 and 4×4 grid scroll chaotic attractors, and the experimental results are also obtained, which is consistent with the numerical simulations.     

校园计算网格作业自适应调度的研究和实现

由于网格资源具有分布、异构、动态、自治等特性。使得网格作业调度成为网格计算中具有挑战性的任务之一。针对校园高性能计算资源负载不均衡、管理模式不统一的问题，提出了校园计算网格自适应调度系统的解决方案。详细研究了网格作业的白适应调度技术，设计了含有负载均衡能力的资源动态信息收集模型，并给出自适应调度算法。实现了校园范围内高性能计算资源的负载均衡和统一的资源管理。     

关于双模栅控行波管栅极电压分开加电的研究

讨论了双模栅控行波管在高／低模两种工作模式下，所需的栅极脉冲电压不一致的原因，及两个栅极加不同的电位对流通率、栅极电流、输出功率及互作用效率的影响。     

LMSS中的遮蔽衰落模式分析

本文对ＬＭＳＳ遮蔽环境中的衰落分布进行了分析，利用现有实验数据和ＥＲＳ模式的基本形式，重新确定了经验模式参数在不同遮蔽条件下与仰角和频率的关系；