A method of evaluating VDT screen layout by eye movement analysis.

The method for evaluating VDT screen layout by eye movements is studied. When the subjects read from the VDT screen, the change in their line of sight was measured by their eye movements. The measured eye movement patterns were divided into the sequential and rereading processes. When related to these characteristics, the performance of subjects was found to be good when the sequential process predominated over the rereading process. The eye movement pattern was shown to change with screen layout. The eye movement pattern proved effective in determining that tabular format is more legible than textual format. This confirmed the usefulness of the method of evaluating VDT screen layout by the eye movement pattern.     

Ergonomic analysis of musculoskeletal discomforts among conversational VDT operators

VDT tasks are rapidly increasing as the office automation prevails. Despite its numerous benefits, occupational hazards such as visual fatigue, eye strain, radiation and musculoskeletal stresses have emerged as an important issue. This study was designed to investigate the effects of work postures and anthropometric differences upon the musculoskeletal stresses experience by operators involved in conversational VDT tasks. Evaluation of the level of muscoloskeletal discomfort was performed for 297 VDT operators from three divisions of telecommunication company in Korea. The ergonomic variables of the VDT tasks and the operators' anthropometric variables were evaluated for 70 out of the 297 VDT operators. Factor analysis is used for identifying underlying pattern of discomfort and multiple regression analysis were performed to examine the relationship between the measured ergonomic variables and the musculoskeletal discomfort. This study indicates that the ergonomic variables have influences on the musculoskeletal discomfort. It is important to provide the workers with fully adjustable workstations so that they can maintain their work postures most suitable for the sustained VDT work. Furthermore, in order to achieve the best working conditions, VDT operators should be given a proper training for the adjustment of their workstations.     

引导文教学法在网页布局与CSS中的应用

引导文教学法是德国职业教育和培训广为采用的一种教学方法,强调培养学生独立学习、工作计划制作、实施和评估的能力。作为教学改革的探索,在网页布局与CSS专业课中采用了引导文教学法,按照引导文教学法的6个步骤进行教学设计。实践表明,教学效果良好。     

A syntactic method for analysis of nystagmus and smooth pursuit eye movement

Eye movements are studied in neurophysiology, neurology, ophthalmology, and otology both clinically and in research. In this article, a syntactic method for recognition of horizontal nystagmus and smooth pursuit eye movements is presented. Eye movement signals, which are recorded, for example, electro-oculographically, are transformed into symbol strings of context free grammars. These symbol strings are fed to an LR(k) parser, which detects eye movements as sentences of the formal languages produced by these LR(k) grammars. Since LR(k) grammars have been used, the time required by the whole recognition method is directly proportional to the number of symbols in an input string.     

An ergonomic assessment of fixed-height, partially adjustable, and fully adjustable VDT workstations by IntelAd

Three types of VDT workstations, namely, fixed-height, partially adjustable, and fully adjustable, are ergonomically evaluated by IntelAd (an Intelligent Computer Workstation Adjustment System). The objective is to investigate how the degree of adjustability of workstation components affects selected groups of computer users in reference to their seated posture. Six population groups (combinations of two sex groups and three population percentiles) are hypothetically tested in this study. The results are then summarized to determine how vulnerable to CTS individual user groups are.     

Where to put the creases? Interactions between hand length,task, screen size,and folding method on the suitability of hand-held foldable display devices

Limited information is available regarding ergonomic foldable display device forms. This two-stage study involving young South Koreans (divided into three hand-length groups) was conducted to determine ergonomic forms for hand-held foldable display devices considering folding/unfolding comfort and preference. Stage I obtained the suitability of three screen sizes for five tasks. Stage II evaluated 14 different bi- and tri-folding methods considering screen size, folding direction, and folding time. The effects of hand length were all non-significant. Screen size preferences were task-dependent; small screens were preferred for making calls, and medium screens for web searching and gaming. Folding methods affected folding/unfolding comfort and preference; outward screen and Z-shape screen folding were the most preferred bi- and tri-fold concepts, respectively. Screen protection and access appeared to be competing factors in the user preference determination process. Foldable screen size and folding method should be determined by considering tasks, folding/unfolding comfort, and user preferences.

Practitioner summary: A 13.5?cm screen was preferred for making calls, whereas a 17.5?cm screen was best for web searching and gaming. An outward bi-fold screen concept with a 17.5?cm screen and Z-shape tri-fold screen concept with a 22.9?cm screen were preferred. Overall, the Z-shape concept was most preferred.

Abbreviations: SD: standard deviation; ANOVA: analysis of variance; H: Height; W: Width; T: Thickness     

Intelligent multimedia layout: A reference architecture for the constraint-based spatial layout of multimedia presentations

With increases in the complexity and dynamics of multimedia information communicated by current applications, there arises a corresponding need towards a standard technology for intelligent multimedia interfaces. In this article, we address those components of an intelligent multimedia presentation system (IMMPS) which deal with the design and the realization of spatial layout. We treat multimedia layout as a multidimensional constraint problem and propose a reference architecture for a general-purpose intelligent multimedia layout manager (IMMLM) that is based on a dedicated constraint solver kernel.     

A survey of computational approaches to three-dimensional layout problems

The component layout or packaging problem requires efficient search of large, discontinuous spaces. This survey paper reviews the state-of-the-art in product layout algorithms. The focus on optimization and geometric interference calculation strategies addresses the common aspects of the layout problem for all applications.     

基于认知规律的用户界面信息布局设计方法

为进一步提高工作效率,提出一种基于人的认知因素和几何位置匹配因素的界面信息布局设计方法。建立任务模型,获取合理的待布局任务信息元素;从人的认知规律中提取3个布局原则,分别将其以定量化的形式构建数学模型,以目标函数变量的形式作用于界面布局过程中;引入带有惯性权重的粒子群算法求解目标函数,对界面中所有待布局元素的几何位置寻求最优布局方案。以隧道应急救援培训系统的决策界面布局为例,提出解决方案并验证该方法的可行性。实验结果表明,该方法具有一定的实用性。     

基于遗传算法的大规模矩形件优化排样

大规模矩形件优化排样是一个典型的组合优化问题，属于NP-hard问题．实际工程中对一个排样方案一般有满足“一刀切”的工艺要求，“一刀切”要求增加了对排样的约束．提出的优化算法，将矩形匹配分割算法作为遗传算法染色体的解码器实现一个排样方案，用遗传算法进行排样方案的全局搜索．算例比较表明，该算法可以求得满足“一刀切”约束的最优解．     

基于触摸显示屏的手势输入字符方法研究

针对触摸显示屏的操作特点,利用简单通用手势——滑动和点击,提出了两种触摸手势输入字符方法。第一种是基于T9键盘的改进输入方法,第二种是基于全键盘的改进输入方法。这两种输入方法节省屏幕使用空间,使用户更易学习的同时降低了误输入机率。     

Solving the design of distributed layout problem using forecast windows: A hybrid algorithm approach

In today’s competitive environment, manufacturing facilities have to be more responsive to the frequent changes in product mix and demand by realigning their organizational structure for minimizing material handling cost. However, manufacturing firms are reluctant to modify the layout as it leads to operation disruption and excess rearrangement cost. In this paper, we present an alternative approach for designing a multi-period layout (i.e., distributed layout) that maintains a tradeoff between re-layout cost and cost of excess material handling. Obtaining an optimal solution to distributed layout problem is generally a difficult task, owing to larger size of quadratic assignment problem. In order to overcome the aforementioned drawback, a meta-heuristic, named ‘CSO-DLP’ (Clonal Symbiotic Operated-Distributed Layout Planning) is developed for designing a distributed layout that jointly determines the arrangement of department and flow allocation among them. It inherits its trait from Symbiotic algorithm and Clonal algorithm. In addition to these; the concept of ‘forecast window’ is used, which evaluates the layout for varying number of periods at a given time. The proposed meta-heuristic is applied on a benchmark dataset and the effect of system parameters, such as rearrangement cost, department disintegration, and duplication are investigated and benchmarked in this paper.     

Effects of color display, color name, color formation and color alignment on the screen layout usability of customized product color combinations

This study investigated the effects of screen layout on the usability of a large number of color combination options for customized product. Using an L₁₈ orthogonal array, 18 interfaces were designed around four factors: color display, color name, color formation and alignment. Participants completed a color combination search task and a questionnaire concerning their satisfaction with the interfaces.Based on the search time and user satisfaction, the display of color samples by modular sections (itemized color chips) was found to be the optimal method of color selection. This arrangement reduced the number of combinations of color samples displayed on the screen and allowed efficient navigation of a large palette of color combinations. Vertical alignment aided the product color discrimination and reduced the search time. Users viewed various product color combinations directly with or without the aid of color names.

Relevance to industry

Because of the considerable observed reductions in search time and the superior reported degrees of satisfaction associated with the tested configurations for customized product color combination, the findings of this study have important ramifications for consumers and manufacturers of products as diverse as sofas, curtains, clothing, athletic shoes, cars, mobile phones and the other customized products.     

A method for the correction of drift in movement analysis

A method is proposed for the correction of drift over cyclic three-dimensional kinematic data during treadmill locomotion. An adaptive least-squares drift correction algorithm (ALSDC) is developed from the operational definition of no drift. This method includes automatic selection of least-squares polynomial degree and sequential processing of large data sets.     

A large screen matrix display using an array of ac plasma display panels

A direct-view large-screen matrix type display using an array of ac plasma display modules has been developed. Its resolution can reach 160 lines m^?1 and 230 lines m^?1: the screen area being expanded according to the user's requirements. It can be used in the areas of alphanumerics and graphics. This paper describes its structure, drive circuit, and some design considerations.     

Biomechanical analysis of upper limb during the use of touch screen: motion strategies identification

Abstract

Nowadays touch technology is growing and developers try to make it ever more intuitive and easier to use. This present work focused on the upper limb joint coordination during the achievement of puzzles on touch screen. A 5-inch and 10-inch devices were used to perform 9 and 16 pieces puzzles dragged with digits. The conclusions showed an increase in joint solicitation with the number of piece and the touch screen size. Moreover, three interactions strategies proved to be an evidence: the ‘wrist strategy’ preferentially implying wrist flexion/extension, the ‘elbow strategy’ preferentially implying the elbow flexion/extension and the ‘neutral strategy’ mobilising equally the two joints. From an ergonomic point of view, the data about how the upper limb segments are mobilised while interacting with the screen could be relevant to increase the adaptability of the devices to the user, including users with motor impairments.

Practitioner Summary: Information about the biomechanical organisation of movement during interaction with touch devices appears relevant in order to develop applications adapted to the motor capacities of users. From the analysis of joint angles when performing several times a puzzle with healthy subjects, three motor strategies were highlighted.     

应用模糊分析法对评价网络信息安全的有效研究

如今网络的普及率令人惊叹,然而由于非法入侵所造成的信息安全隐患时时刻刻都存在着.为了尽量降低非法入侵给网络带来的损害并避免此类安全隐患,如今研发出了一种名为模糊层次分析法的网络安全态势评估模型,首先完成对网络安全指标体系的构建,运用参差分析法对计算机各评估指标进行权重和分析.最后采用模糊分析法来建立一个网络信息安全态势一致性评判标准,最终达到综合评估网络信息安全态势的目的.相关研究结果表明,这种模糊层次分析法能够在很大程度上提升网络信息安全态势评估的准确度,结果更加精确而客观,实用性很强.文章旨在对网络信息安全评估的问题进行研究.     

Evaluation of upper-limb function by the sensor pegboard test method

Man moves his hands and arms to create things. These movements may be constructed as activities to change the environment favourably. Such movements result from co-ordinated control of the musculoskeletal system, by the hierarchical central nervous system. Man develops his working ability through learning, evaluation of the co-ordinated working ability of the highly advanced motor and sensory central nervous systems in addition to the ability to conduct a series of simple movements may produce valuable results which could be helpful in evaluating finger working ability.

The sensor pegboard test method was developed in this study. The upper-limb motions of the subjects as they perform various specified tasks are measured and evaluated at the micromotion level (micromotion is defined here as the smallest motion element that can be distinguished with the sensor pegboard). This method can produce immediate results, which are not obtainable by conventional time and motion study methods, and can evaluate many aspects of the capability of the upper-limb of workers. Using this method, the change in the upper-limb capability as a result of ageing was quantitatively determined, and its overall picture was clarified.     

The effect of page layout on mental workload: A dual-task experiment

In two dual-task experiments, the effects of page layout on mental workload were explored. Previous studies indicate that it is preferable to present a text document on paper than to display it on a computer screen (e.g. Mayes, D. K., Sims, V. K., & Koonce, J. M. (2001). Comprehension and workload differences for VDT and paper-based reading. International Journal of Industrial Ergonomics, 28(6), 367–378; Wastlund, E., Reinikka, H., Norlander, T., & Archer, T. (2005). Effects of VDT and paper presentation on consumption and production of information: Psychological and physiological factors. Computers in Human Behavior, 21, 377–394). However, critics have advocated improper matching of the materials between the two media as a confounding variable e.g. (Noyes, J. M., & Garland, K. J. (2003). VDT versus paper-based text: reply to Mayes, Sims and Koonce. International Journal of Industrial Ergonomics, 31(6), 411–423). The focus of the present study has been to take one such variable, page layout, and then isolate and replicate it onscreen in order to assess its affect on user performance. The results of the present experiments showed that optimizing the page layout for onscreen viewing decreased mental workload. This not only confirms the importance of matching all aspects of the presentational modes in doing paper vs. computer comparisons, but also shows that reading from a computer screen can be facilitated by creating documents with a page layout that is adapted to the screen which they are intended to be presented on.     

A method for the recovery of noisy missing data in movement analysis

A new method is proposed for the accurate recovery of missing marker data obtained from movement tracking systems. The method has the form of a least-squares cubic polynomial approximation which is realized by the recursive expansion of orthogonal polynomials.