态势估计中的想定模型和仿真技术

通过仿真模拟获得战场数据及态势估计中算法训练、评价所需的数据类型与数量。将本体引入群体组织建模技术中,并结合作战想定生成的特点和作战仿真的需求,实现了一个基于本体的群体组织想定模型。研究表明可以通过仿真训练或者测试态势来估计分类器。     

Cooperative prediction guidance law in target-attacker-defender scenario

Dear editor, The defending guidance problem for the target-attackerdefender (TAD) scenario is a challenge.The attacker (A) refers to the attacking missile, whos...     

Learning styles assessment and theoretical origin in an E-learning scenario: a survey

The performance of the learners in E-learning environments is greatly influenced by the nature of the posted E-learning contents. In such a scenario, the performance of the learners can be enhanced by posting the suitable E-learning contents to the learners based on their learning styles. Hence, it is very essential to have a clear knowledge about various learning styles in order to predict the learning styles of different learners in E-learning environments. However, predicting the learning styles needs complete knowledge about the learners past and present characteristics. Since the knowledge available about learners is uncertain, it can be resolved through the use of Fuzzy rules which can handle uncertainty effectively. The core objective of this survey paper is to outline the working of the existing learning style models and the metrics used to evaluate them. Based on the available models, this paper identifies Felder–Silverman learning style model as the suitable model for E-learning and suggests the use of Fuzzy rules to handle uncertainty in learning style prediction so that it can enhance the performance of the E-learning system.     

How a Pareto frontier complements scenario projections in land use change impact assessment

To evaluate the sustainability of potential agricultural land developments, scenario projections with land use change models are often combined with environmental impact assessments. Although this allows inter-scenario comparison of impacts, it does not permit interpretation of scenarios in the light of theoretically optimal impacts. A Pareto frontier provides this information. We demonstrate this for ethanol production in Goiás, Brazil, in 2030. For a Business-as-Usual scenario projection, the spatial configuration, production costs, and GHG emissions of the production chain are compared with those obtained from spatial optimization and summarized by the Pareto frontier. Projected production costs are 729 $/m³ ethanol, with GHG emissions of 40 kg CO₂-eq/m³ ethanol. The Pareto frontier indicates an improvement potential of ∼50 $/m³ ethanol when keeping emissions fixed, or ∼250 kg CO₂-eq/m³ ethanol when keeping costs fixed. Robust locations having low costs and emissions show where and how improvements are reached, offering instruments for policy (re)design.     

Subjective operational reliability assessment of maritime transportation system

System reliability assessment is one of the major acts in the operation and maintenance of every industrial and service sector, which also holds true for maritime transportation system. The complexity of the maritime transportation system is a prime obstacle in the evaluation of the operational reliability of the system; mainly due to the fact that statistical data on the important parameters and variables is scarce. This makes the application of fuzzy sets and fuzzy logic a viable option to overcome the data problem with regards to imprecision or vagueness in parameters and variables values. In this paper, the different decisive factors, affecting maritime transportation systems, are modeled in the form of linguistic variables. Techniques such as aggregation, mapping of fuzzy sets using distance measure and fuzzy logic rule base are used to arrive at subjective operational reliability value. The complete procedure is demonstrated with an example.     

Cooperative autonomous search,grasping, and delivering in a treasure hunt scenario by a team of unmanned aerial vehicles

This paper addresses the problem of autonomous cooperative localization, grasping and delivering of colored ferrous objects by a team of unmanned aerial vehicles (UAVs). In the proposed scenario, a team of UAVs is required to maximize the reward by collecting colored objects and delivering them to a predefined location. This task consists of several subtasks such as cooperative coverage path planning, object detection and state estimation, UAV self‐localization, precise motion control, trajectory tracking, aerial grasping and dropping, and decentralized team coordination. The failure recovery and synchronization job manager is used to integrate all the presented subtasks together and also to decrease the vulnerability to individual subtask failures in real‐world conditions. The whole system was developed for the Mohamed Bin Zayed International Robotics Challenge (MBZIRC) 2017, where it achieved the highest score and won Challenge No. 3—Treasure Hunt. This paper does not only contain results from the MBZIRC 2017 competition but it also evaluates the system performance in simulations and field tests that were conducted throughout the year‐long development and preparations for the competition.     

Measurements of team workload: A time pressure and scenario complexity study for maritime operation tasks

Workload is a critical factor influencing team performance in complex systems. There remains no consensus on the selection of team workload measures. Through an experiment based on simulated maritime operation tasks, team workload was manipulated by time pressure and scenario complexity to investigate the responses of three categories (subjective, performance-based, and physiological) of potential team workload measurements. The results show that time pressure had significant effects on all the three categories of measurements, especially on subjective indicators, miss rate, completion rate, operation accuracy, and eye movements. Significant main effects of scenario complexity on subjective team workload and the selected team performance measurements were also found, such as response latent time, miss rate, completion rate, and operation accuracy. Physiological measurements may not be sensitive for measuring team workload when scenario complexity serves as a major influencing factor of team workload.     

网络安全态势感知中态势评估关键技术研究

提出了一种安全态势评估模型。利用反正切函数和修正函数来设计证据理论中的经验函数,将证据理论引入到安全态势评估中,对部署在网络中的多种传感器设备提供的安全数据进行关联、融合,绘制安全态势曲线,给出当前网络的安全态势。对所提出的安全态势评估模型和算法进行了测试、验证。结果表明证据理论的应用很好地解决了网络安全态势评估问题。介绍了如何将这种评估模型应用到大规模网络安全态势评估中去。     

基于Ontology的态势估计研究

根据信息资源所具有的领域知识含义,进行语义融合从而支持高级别推理在信息融合中尤为重要.通过对态势估计的形式化描述,提出了基于Ontology的态势估计研究方法,利用本体的扩展使得态势信息更富有语义,从而提高推理阶段的效率.讨论了用于促进异构数据和信息源进行信息融合以支持态势估计融合处理的本体的角色问题以及相关构建方法,为高层信息融合研究提供了新的思路及有益的理论参考.     

Team situation assessment and information distribution

Described is the cooperative work of constructing team situation awareness within two teams of a military command and control unit. Specifically discussed is how the distributed cognitive and cooperative work of decision-making of the two teams is structured. The situation enabled two different ways of distributing information within the team: one serial and one parallel. One team chose the parallel information transfer, the other the serial one. Discussed is the interaction patterns that emerge in the respective teams and their consequences for situation assessment and situation awareness. The differences are then discussed in terms of means of sharing information. Some hypotheses for future research are also offered.     

Team situation assessment and information distribution

Described is the cooperative work of constructing team situation awareness within two teams of a military command and control unit. Specifically discussed is how the distributed cognitive and cooperative work of decision-making of the two teams is structured. The situation enabled two different ways of distributing information within the team: one serial and one parallel. One team chose the parallel information transfer, the other the serial one. Discussed is the interaction patterns that emerge in the respective teams and their consequences for situation assessment and situation awareness. The differences are then discussed in terms of means of sharing information. Some hypotheses for future research are also offered.     

一种面向态势估计中分群问题的聚类方法

对目标分群技术问题进行了描述,分群或聚类问题是态势估计需要实现的一个重要功能,主要根据底层融合的结果应用聚类分析法实现战场目标分群。目标分群的结果有助于确定态势元素之间的相互关系,从而解释问题领域的各种行为,辅助指挥决策。提出使用CHAMELEON算法对战场目标或群进行划分,根据相对互连性RI和相对近似性RC所表征的相似度把它们形成更高层次的群。     

一种细粒度的网络威胁态势评估方法

针对现有网络威胁态势评估方法评估粒度较粗,无法满足不同管理人员评估需求的问题,提出了一种细粒度的网络威胁态势评估方法。按照从局部到整体、从微观到宏观的评估策略,分别对威胁节点、威胁链路、威胁路径、威胁目标和全网威胁态势进行评估,实现了对网络威胁的深入分析和细粒度评估,通过实验分析证明了评估结果的合理性和准确性。     

Process situation assessment: From a fuzzy partition to a finite state machine

Process situation assessment plays a major role in supervision of complex systems. The knowledge of the system behavior is relevant to support operators in their decision tasks. For complex industrial processes such as chemical or petrochemical ones, most of supervision approaches are based on data acquisition techniques and specifically on clustering methods to cope with the difficulty of modeling the process. Consequently, the system behavior can be characterized by a state space partition. This way, situation assessment is performed online through the tracking of the system evolution from one class to another. Furthermore, a finite state machine that is a support tool for process operators is elaborated to model the system behavior. This article presents theoretical aspects according to which the intuition that the trajectory observation of a dynamical system by a sequence of classes, to which the actual state belongs, gives valuable information about the real behavior of the system is substantiated. Thus, practical aspects are developed on the state machine construction and illustrated by two simple applications in the domain of chemical processes.     

改进的超视距空战态势评估方法

根据现代超视距空战的特点,结合目前超视距空战态势评估模型的不足,提出了一种改进的态势评估模型。该模型针对战机在超视距空域内寻找目标、互射导弹实施打击的特点,以载机速度、高度、空战能力、雷达探测性能,以及导弹攻击性能等作为主要研究对象,分析并建立了武器运用优势函数、飞行状态优势函数以及空战能力优势函数,用加权综合的方法得到双方的优势函数,模型更符合现代超视距空战实战特点。大量的数据仿真和实例应用结果验证了该评估算法的有效性。     

动态贝叶斯网络在战术态势估计中的应用*

针对战术态势估计的特点和要求,分析和建立了应用于态势估计的动态贝叶斯网络模型。该模型以离散变量集为研究对象。由于该动态贝叶斯网络满足Markovian特性和平稳特性,降低了网络的复杂度。相比较于贝叶斯网络模型,该动态贝叶斯网络模型考虑了时序因素,将前时刻的态势因素作为当前时刻态势估计的证据的一部分,并能对下一时刻的态势进行预测。文中采用集树（junction tree）算法,利用相关的贝叶斯网络推理软件进行了实验,实验结果表明基于动态贝叶斯网络的估计结果较贝叶斯网络的估计结果好,验证了该模型的有效性。     

Estimation of sea state from Sentinel-1 Synthetic aperture radar imagery for maritime situation awareness

A new empirical algorithm CWAVE_S1-IW for estimation of significant wave height H_s including swell and wind sea from C-band satellite-borne Synthetic Aperture Radar (SAR) data has been developed for Sentinel-1 (S1) Interferometric Wide Swatrh Mode (IW) imagery. The algorithm was implemented into the Sea Sate Processor (SSP) for fully automatic processing for near real time (NRT) services and allow the estimation of wave fields of thousands of kilometres in the flight direction and 250 km swath from S1 IW scenes consisting of a sequence of individual images.

The priority of CWAVE_S1-IW development was an automatic, fast and robust raster processing independent of wave patterns, applicable even when only clutter is visible in the SAR images. The algorithm is based on the spectral analysis of subscenes in wavenumber space. The empirical function allows direct H_s estimation from image spectra without first converting them into wave spectra and uses integrated image spectra parameters as well as estimated local wind information. A texture analysis based on Grey Level Co-occurrence Matrices (GLCM) is also applied. In this way, also the parameters of short waves can be estimated, which are not visible in S1 IW images and are only represented by clutter.

The algorithm was tuned worldwide using in-situ collocated measurements of 92 buoys with more than 2500 acquisitions. The validated SSP allows automatic processing of worldwide S1 IW images in VV or HH polarization, including Atlantic storms, cyclones, and huge storms in the Gulf of Alaska with a root-mean-square (RMSE) error of 80 cm for H_s. For the closed seas like the North Sea, Baltic Seas and Black Sea the accuracy is higher with an RMSE = 55 cm. The algorithm is integrated into a demonstration service, used for further validation at the DLR ground station in Neustrelitz. The NRT processing has been tested by supporting a research ship cruise in the Antarctic Sea.     

Implementation of a situation awareness assessment tool for evaluation of human-robot interfaces

In this paper, we outline a methodology for evaluating the situation awareness (SA) provided by a supervisory interface for an autonomous on-road vehicle. Our goal is to be able to use the evaluations to compare interface designs with respect to how well each facilitates the users' acquisition of SA. We used Endsely's Situation Awareness Global Assessment Technique (SAGAT) (Endsely, 1988) and developed scenarios and assessment questions appropriate for supervisors of autonomous on-road driving vehicles. We describe the results of two experiments used to refine our SA assessment implementation. In a third experiment, we applied the refined implementation to a graphical user interface we developed to test the sensitivity of our SAGAT implementation. We discuss the results of this experiment and implications for applying the SAGAT methodology to supervisory user interfaces for autonomous vehicles.     

Collaborative concept mapping activities in a classroom scenario

The aim of this study is to test collaborative concept mapping activities using computers in a classroom scenario and to evaluate the possibilities that Elkar-CM offers for collaboratively learning non-technical topics. Elkar-CM is a multi-lingual and multi-media software program designed for drawing concept maps (CMs) collaboratively. Concept mapping is a widely accepted technique that promotes meaningful learning. Graphically representing concepts of the learning domain and relationships between them helps students integrate new knowledge into their current cognitive structure. This study was carried out with Social Education degree students at the University of the Basque Country (UPV/EHU). The experiment included two learning activities. First, all students collaboratively constructed in the classroom a CM on the subject of Moral Development. Second, students were organised into groups to complete the CM generated in the first part.