Ship detection performance using simulated dual-polarization RADARSAT constellation mission data

The RADARSAT Constellation Mission (RCM) planned to be launched in 2018 is designed to support maritime surveillance requirements in which ice, wind, oil pollution, and ships are to be monitored by providing wide swath beam modes. In this article, we introduce the first analysis of ship detection performance using simulated RCM data. We report ship detection performance using a likelihood ratio test (LRT) for three wide swath RCM imaging modes: Ship Detection (25 m), Low Resolution (100 m), and Medium Resolution (50 m). These beam modes were assessed for a number of dual-polarimetric (dual-pol) systems, including the standard linear polarizations as well as compact polarimetry (CP). These data were simulated from RADARSAT-2 Fine Quad (FQ) mode in the three RCM modes. Furthermore, the detection performance of the pseudo-quad data reconstructed from the simulated circular transmit, linear receive data is also investigated and compared to the other systems’ performance for the three RCM modes. The receiver operating characteristic curves are used in this study as the basic measure of detection performance for all beam modes and all detectors. We found that the compact polarimetric SAR detectors outperform the conventional linear dual-pol detectors at the three RCM modes for ship detection for medium to high incidence angles. At steep angles, the performance of the two polarization configurations was comparable. Our study confirmed that detection performance improved as incidence angle and spatial resolution increased. We also investigated the impact of the ship orientation with respect to the radar beam and found that detection performance was generally higher when ship was oriented perpendicular to the radar beam.     

Generalized additive neural network with flexible parametric link function: model estimation using simulated and real clinical data

Neural Computing and Applications - Artificial neural networks have been proposed in medical research as an alternative to some regression models such as the generalized linear models, being the...     

基于模拟退火的多标记数据特征选择

多标记数据有很多的冗余特征和数据,为了解决多标记数据中冗余和无关特征,提高多标记学习算法的泛化能力。提出一个基于模拟退火的卷积式特征选择方法——SAML(simulated annealing based feature selection for multi-label data),已有的算法只是使用了遗传算法来进行优化,新算法采用模拟退火来寻找最优子集,其效果在已有的工作中表现出比前者遗传算法更好的效果。在用于公开评测的Yahoo网页分类数据集上的实验结果表明,SAML算法的性能优于新近提出的一些流行的多标记特征选择方法。     

Cognition and the temporal arts: Investigating audience response to dance using PDAs that record continuous data during live performance

If artists and art explore organization of the brain [Zeki, S., Lamb, M., 1994. The neurology of kinetic art. Brain 117, 607–636], then investigation of response to artistic performance holds promise as a window to perceptual and cognitive processes. A new instrument for recording real-time audience response – the portable Audience Response Facility (pARF) – is described. Twenty, hand-held, Personal Digital Assistants (PDAs) collect responses on customizable skin interfaces. The pARF server transmits the customizable options, synchronizes devices and collects data for export. We report two studies using the pARF that demonstrate respondent agreement of perceived emotion during particular sections of two dance works. Greater agreement was evident in continuous ratings of arousal than valence; arousal appears to be related to surface features of the dance work. Future applications of the pARF to studies of multi-modal perception and cognition are discussed.     

Investigating haptic distance-to-break using linear and nonlinear materials in a simulated minimally invasive surgery task

Accurate detection of mediated haptic information in minimally invasive surgery (MIS) is critical for applying appropriate force magnitudes onto soft tissue with the aim of minimising tissue trauma. Force perception in MIS is a dynamic process, with surgeons’ administration of force into tissue revealing information about the remote surgical site which further informs the surgeons’ haptic interactions. The relationship between applied force and material deformation rate provides biomechanical information specifying the deformation distance remaining until a tissue will fail: which is termed distance-to-break (DTB). The current study demonstrates that observers can detect DTB while deforming simulated tissues and stop before reaching the tissues’ failure points. The design of training simulators, control devices and automated robotic systems for applications outside of MIS is discussed.

Practitioner Summary: In MIS, haptic information is critical for applying appropriate forces onto soft tissue to minimise tissue trauma. Observers used force information to detect how far they could deform a virtual tissue before it would break. The design of training simulators, control devices and automated robotic systems is discussed.     

Experimenting with local networks using an integrated circuit data link controller

There has been considerable discussion recently about the implementation of local networks. Much of this discussion centres around techniques requiring special hardware which is often too expensive for the application or not yet available. There is, however, an immediate need for local networks of a more modest price and performance. This paper describes the use of an integrated circuit data link controller to implement an inexpensive low performance local network.     

Attentional models of multitask pilot performance using advanced display technology

In the first part of the reported research, 12 instrument-rated pilots flew a high-fidelity simulation, in which air traffic control presentation of auditory (voice) information regarding traffic and flight parameters was compared with advanced display technology presentation of equivalent information regarding traffic (cockpit display of traffic information) and flight parameters (data link display). Redundant combinations were also examined while pilots flew the aircraft simulation, monitored for outside traffic, and read back communications messages. The data suggested a modest cost for visual presentation over auditory presentation, a cost mediated by head-down visual scanning, and no benefit for redundant presentation. The effects in Part 1 were modeled by multiple-resource and preemption models of divided attention. In the second part of the research, visual scanning in all conditions was fit by an expected value model of selective attention derived from a previous experiment. This model accounted for 94% of the variance in the scanning data and 90% of the variance in a second validation experiment. Actual or potential applications of this research include guidance on choosing the appropriate modality for presenting in-cockpit information and understanding task strategies induced by introducing new aviation technology.     

Evaluation of global fire detection algorithms using simulated AVHRR infrared data

This paper provides a comparison of selected algorithms that have been proposed for global active fire monitoring using data from the NOAA Advanced Very High Resolution Radiometer (AVHRR). A simple theoretical model was used to generate scenes of AVHRR infrared channel 3 and channel 4 data containing fires of various sizes and temperatures in a wide range of terrestrial biomes and climates. Three active fire detection algorithms were applied to the simulated AVHRR images and their performance was characterized in terms of probability of fire detection and false alarm as functions of fire temperature and area, solar and viewing geometry, visibility, season and biome. Additional comparisons were made using AVHRR imagery. Results indicate that while each algorithm has a comparable probability of detecting large (1000m2) fires in most biomes, substantial differences exist in their ability to detect small fires, their tolerance of smoke and neighbouring fires, the number of false alarms, and their overall suitability for global application. An improved automatic algorithm is finally presented. It offers enhanced active fire detection with comparable or reduced false alarm rates in most biomes.     

VisuaLeague: Player performance analysis using spatial-temporal data

In recent years, the phenomenon of eSports has been a growing trend and consequently, in addition to players, other groups of users, including coaches and analysts, took an interest in online video games and the data extracted from them. Among many types of video games, one of the most widely played is the MOBA (Multiplayer Online Battle Arena) League of Legend (LoL) game. Similary to traditional sports, players and coaches/analysts analyse all game events, such as, players’ movements, to understand how they play to define new strategies and improve their performance. Our main goal is to get a better understanding of which visualizations techniques are more adequate to handle this type of spatio-temporal information data, associated to player performance analysis in video games. To address this goal, we inquired players to identify the analytical questions they need to support for performance analysis and designed the VisuaLeague prototype for the visualization of in-game player trajectories, using animated maps, and events during a LoL match. This paper presents a user study to evaluate the adequacy of animated maps and the analytical strategies followed by players when using spatio-temporal data to analyse player performance. The results support the adequacy of using the animated maps technique to convey information to users in this context. Moreover, they also point out towards a high degree of importance given to the spatio-temporal components of the data for player performance analysis.

     

Knowledge acquisition from questionnaire data using simulated breeding and inductive learning methods

Marketing decision making tasks require the acquisition of efficient decision rules from noisy questionnaire data. Unlike popular learning-from-example methods, in such tasks, we must interpret the characteristics of the data without clear features of the data nor pre-determined evaluation criteria. The problem is how domain experts get simple, easy-to-understand, and accurate knowledge from noisy data.

This paper describes a novel method to acquire efficient decision rules from questionnaire data using both simulated breeding and inductive learning techniques. The basic ideas of the method are that simulated breeding is used to get the effective features from the questionnaire data and that inductive learning is used to acquire simple decision rules from the data. The simulated breeding is one of the Genetic Algorithm based techniques to subjectively or interactively evaluate the qualities of offspring generated by genetic operations.

The proposed method has been qualitatively and quantitatively validated by a case study on consumer product questionnaire data: the acquired rules are simpler than the results from the direct application of inductive learning; a domain expert admits that they are easy to understand; and they are at the same level on the accuracy compared with the other methods.

Furthermore, we address three variations of the basic interactive version of the method: (i) with semiautomated GA phases, (ii) with the relatively evaluation phase via AHP, and (iii) with an automated multiagent learning method.     

Bayesian estimation of survival and capture probabilities using logit link and photoidentification data

We develop a series of Bayesian statistical models for estimating survival of wild populations monitored using capture-recapture experiments and photoidentification data. The proposed methodology is based on Cormack-Jolly-Seber model [Cormack, R.M., 1964. Estimates of survival from the sighting of marked animals. Biometrika 51, 429-438; Jolly, G.M., 1965. Explicit estimates from capture-recapture data with both death and immigration—stochastic model. Biometrika 52, 225-247; Seber, G.A.F., 1965. A note on the multiple recapture census. Biometrika 52, 249-259]. Besides time effects in capture probabilities, the proposed models allow taking into account heterogeneity in capture probability caused by the existence of different groups of individuals in the population. For that purpose, the capture probabilities are fitted using a logistic model. Additionally, it is also possible to estimate group-specific survival rates. Goodness of fit is evaluated using Bayes factor methodology. The models are applied to an 11-year photoidentification capture-recapture experiment for bowhead whales, Balaena mysticetus. The best model provides an estimate close to the one obtained by Zeh et al. [2002. Survival of bowhead whales, Balaena mysticetus, estimated from 1981-1998 photoidentification data. Biometrics 58, 832-840] using the Jolly-Seber model, but accounting for heterogeneity in capture probabilities improves precision.     

A high speed computer-to-computer data link

The ICL 1905E at Queen Mary College, London and the CDC 6600 at the University of London Computer Centre, have been linked by a 48 kilobaud Post Office line. Jobs can be transmitted from the 1905E to the 6600, and resuts returned to the 1905E. A modified CDC data terminal (the QSE 2815) is installed at QMC, and is connected to the 1905E through a peripheral channel via a British Standard Interface converter. Standard CDC data transmission procedures are used; the software system is based on the CDC IMPORT/EXPORT package, with a program in the 1905E simulating the operation of IMPORT The 1905E software was written in two parts: an off-lining package which writes batches of programs to magnetic tape, and subsequently prints off-line output from tape, and a link control program which reads program batches from tape for transmission to the 6600, and writes to tape the output received from the link. This off-lining technique ensures that the full capacity of the high speed line is realized The link system began operation at the beginning of 1970, and is now used regularly to transmit jobs to ULCC and other sites in the network. Work is continuing on the provision of network facilities, and an integration of the link system with the operating system in the 1905E.     

数据链路层安全研究

数据链路层安全风险的大小和发生的概率决定了整个数据链路层的安全.有效的安全风险评估有助于检测系统的安全防护,降低数据链路层的安全风险,并提高检测系统的抵御安全风险的能力.在贝叶斯网络和D-S证据理论的基础上,结合这两种方法,对数据链路层影响因素进行了量化,得到数据链路层的风险值.然后构建了系统的节点模型和进程模型.最后...     

A rule-based pilot performance model

A new method of modelling task execution time and its relationship to resource utilization has been developed in this study in order to simulate accurately pilot performance in a single-seat fighter aircraft. By developing the model in a rule-based expert system program, it is suitable for incorporation in an intelligent decision support system to help manage pilot workload and improve total man-machine system performance. This model can also be employed in the design of new aircraft crewstations to analyse new man-machine system interfaces. Validation of the model was accomplished through comparison of critical predicted measures of merit against observed pilot performance in a manned flight simulator.     

Improving classification performance using unlabeled data: Naive Bayesian case

In many applications, an enormous amount of unlabeled data is available with little cost. Therefore, it is natural to ask whether we can take advantage of these unlabeled data in classification learning. In this paper, we analyzed the role of unlabeled data in the context of naive Bayesian learning. Experimental results show that including unlabeled data as part of training data can significantly improve the performance of classification accuracy.     

A wideband data link computer simulation model

This paper describes a computer simulation model capable of predicting the performance of a high data rate end-to-end communication system for biphase and quadriphase CPSK transmission. Simulation results are compared with laboratory measurements in order to verify the simulation procedure. Ultimately, the simulation model is utilized to conduct a parameter sensitivity analysis for the purpose of evaluating the effect of different signal distortion phenomena on link performance.     

数据链路层拓扑发现算法的研究

阐述了网络层拓扑发现与数据链路层拓扑发现之间的区别,分析了数据链路层拓扑发现的研究现状和存在的不足。为改进这一不足,在总结子网内部的直接连接定理和间接连接定理的基础上,提出了一种新的数据链路层拓扑发现算法,并结合该算法,利用树的后序遍历算法作为拓扑图形的显示方法,开发了具有数据链路层拓扑发现功能的网络拓扑系统。     

一种符合EPCCIG2协议的RFID反向链路数据解码技术的实现

针对物联网协议EPcc1G2中反向链路数据的解码技术,以精简硬件资源和提高解码效率为目标,给出了基于MCU硬件平台,并利用其中TIMER模块和ADC模块实现反向链路数据解码技术的设计分析和实现思路,同时以实际运用中对FM0解码实现为实例,对解码效果、关键技术点进行了分析;还在结论中将此解码技术与常用技术方案进行了扼要比较,阐明了相关技术特点,得出了本技术的比较优势。     

The effects of using a portable music player on simulated driving performance and task-sharing strategies

This study examined the effects of performing scrollable music selection tasks using a portable music player (iPod Touch™) on simulated driving performance and task-sharing strategies, as evidenced through eye glance behaviour and secondary task performance. A total of 37 drivers (18–48 yrs) completed the PC-based MUARC Driver Distraction Test (DDT) while performing music selection tasks on an iPod Touch. Drivers’ eye glance behaviour was examined using faceLAB eye tracking equipment. Results revealed that performing music search tasks while driving increased the amount of time that drivers spent with their eyes off the roadway and decreased their ability to maintain a constant lane position and time headway from a lead vehicle. There was also evidence, however, that drivers attempted to regulate their behaviour when distracted by decreasing their speed and taking a large number of short glances towards the device. Overall, results suggest that performing music search tasks while driving is problematic and steps to prohibit this activity should be taken.