The Display of Electronic Commerce within Virtual Environments

In today’s competitive business environment, the majority of companies are expected to be represented on the Internet in the form of an electronic commerce site. In an effort to keep up with current business trends, certain aspects of interface design such as those related to navigation and perception may be overlooked. For instance, the manner in which a visitor to the site might perceive the information displayed or the ease with which they navigate through the site may not be taken into consideration. This paper reports on the evaluation of the electronic commerce sites of three different companies, focusing specifically on the human factors issues such as perception and navigation. Heuristic evaluation, the most popular method for investigating user interface design, is the technique employed to assess each of these sites. In light of the results from the analysis of the evaluation data, virtual environments are suggested as a way of improving the navigation and perception display constraints.     

Effectiveness of image-based mnemonic techniques for enhancing the memorability and security of user-generated passwords

Complex passwords are hard to remember, so people often pick simple passwords, write complex ones down, and reuse the same password across multiple accounts. Proactive password checking (PPC) restrictions and mnemonic techniques can enhance password security and memorability. Participants in this study were assigned to one of three password generation groups: PPC restrictions alone, image-based mnemonic, or text-based mnemonic. They were asked to generate and later recall passwords for five separate fictitious online accounts. The use of mnemonic techniques resulted in the generation of longer and more complex passwords. Furthermore, passwords were more accurately recalled when they were generated using the image-based mnemonic technique or PPC restrictions alone, as opposed to the text-based mnemonic technique. However, passwords generated using PPC restrictions alone were more easily forgotten and susceptible to being cracked. Thus, the image-based mnemonic technique was shown to be the most effective method for generating secure and memorable passwords.     

Cognitive Analysis of Intraoperative Critical Events: A Problem-Driven Approach to Aiding Clinicians’ Performance*

Human error is responsible for a large proportion of the anaesthesia mishaps that occur annually in the United States. Ventilation-related events (VRE) constitute a significant number of anaesthesia critical incidents. Monitoring equipment and their displays extend anaesthesiologists’ resources during VRE but at the expense of additional cognitive demands. This project is a cognitive analysis of intraoperative (inside the operating room) VRE. Goal–means networks were utilised to build a problem-solving model of clinicians’ management of patients’ ventilation during anaesthesia and to map the demands of VRE. The model was also used to identify challenging VRE that were then simulated using a comprehensive anaesthesia simulator. The response of eight experienced clinicians was captured on videotape and analysed to investigate the effectiveness of medical equipment in supporting clinical decision making during VRE.     

A Kinect-based system for cognitive rehabilitation exercises monitoring

In this paper, a 3D computer vision system for cognitive assessment and rehabilitation based on the Kinect device is presented. It is intended for individuals with body scheme dysfunctions and left–right confusion. The system processes depth information to overcome the shortcomings of a previously presented 2D vision system for the same application. It achieves left and right-hand tracking, and face and facial feature detection (eye, nose, and ears) detection. The system is easily implemented with a consumer-grade computer and an affordable Kinect device and is robust to drastic background and illumination changes. The system was tested and achieved a successful monitoring percentage of 96.28%. The automation of the human body parts motion monitoring, its analysis in relation to the psychomotor exercise indicated to the patient, and the storage of the result of the realization of a set of exercises free the rehabilitation experts of doing such demanding tasks. The vision-based system is potentially applicable to other tasks with minor changes.     

Thermal effects on human performance in office environment measured by integrating task speed and accuracy

We have proposed a method in which the speed and accuracy can be integrated into one metric of human performance. This was achieved by designing a performance task in which the subjects receive feedback on their performance by informing them whether they have committed errors, and if did, they can only proceed when the errors are corrected. Traditionally, the tasks are presented without giving this feedback and thus the speed and accuracy are treated separately. The method was examined in a subjective experiment with thermal environment as the prototypical example. During exposure in an office, 12 subjects performed tasks under two thermal conditions (neutral & warm) repeatedly. The tasks were presented with and without feedback on errors committed, as outlined above. The results indicate that there was a greater decrease in task performance due to thermal discomfort when feedback was given, compared to the performance of tasks presented without feedback.     

Structural equation modeling the use of a risk assessment instrument in child protective services

Risk assessment instruments have been developed to help human service workers identify risk factors associated with abusive families. Many such instruments have been incorporated into management information systems in the form of Decision Support Systems (DSS). This paper reports findings from a case study that evaluated a risk assessment instrument as a decision support tool. Respondents considered “usefulness” of the information a more important factor than how easy the system was to use, the configuration of reports or whether the system was up or not. Focus groups were used to explore how to increase the usefulness of the information.     

The use and impact of human resource information systems on human resource management professionals

Human resource information systems (HRIS) usage allows the human resource (HR) professional to become a strategic player. With both increasing functionality and affordability, HRIS are being used extensively in organisations of all sizes. Despite this, surprisingly little is know about the current usage, whether disparities exist between companies of different sizes, or about the impact HRIS has on the general professional standing of the HR professional.     

用蒙特卡罗方法计算光子外照射对人体产生的有效剂量

采用雌雄同体的成人人体模型和蒙特卡罗方法(MCNP4C)计算了环境γ射线外照射对人体产生的有效剂量.为了便于比较,计算中选用了ICRP 74号出版物中给出的20种不同的γ光子能量以及从前向后照射和从后向前照射两种辐照几何源.对计算结果进行比较发现,MCNP4C程序计算得到的结果与ICRP 74号出版物中给出的结果非常吻合.     

Spatio-temporal crowd density model in a human detection and tracking framework

Recently significant progress has been made in the field of person detection and tracking. However, crowded scenes remain particularly challenging and can deeply affect the results due to overlapping detections and dynamic occlusions. In this paper, we present a method to enhance human detection and tracking in crowded scenes. It is based on introducing additional information about crowds and integrating it into the state-of-the-art detector. This additional information cue consists of modeling time-varying dynamics of the crowd density using local features as an observation of a probabilistic function. It also involves a feature tracking step which allows excluding feature points attached to the background. This process is favorable for the later density estimation since the influence of features irrelevant to the underlying crowd density is removed. Our proposed approach applies a scene-adaptive dynamic parametrization using this crowd density measure. It also includes a self-adaptive learning of the human aspect ratio and perceived height in order to reduce false positive detections. The resulting improved detections are subsequently used to boost the efficiency of the tracking in a tracking-by-detection framework. Our proposed approach for person detection is evaluated on videos from different datasets, and the results demonstrate the advantages of incorporating crowd density and geometrical constraints into the detection process. Also, its impact on tracking results have been experimentally validated showing good results.