二维视觉搜索中成功扫视幅度中值与视力角

用二维视觉搜索实验中的成功扫视幅度中值来量度视力角.通过对成功扫视幅度的 计算和分析,研究了视力角与搜索场景对比度,及干扰物体密度的关系,并揭示了扫视眼动是 由全局搜索策略和瞬间周边视觉信息的引导所共同控制.最后用正态分布模型来模拟视力 角,通过选择适当参数,所给出的函数式能较好地拟合实验数据,并能反映出场景对比度和干 扰物密度之间的互补关系.     

Fitts’ 模型在移动与可穿戴计算交互中的可用性研究*

近年来移动计算与可穿戴计算范式已进入高速发展期,此类计算范式通常采用基于手持小屏幕与头戴显示器的受限视场显示技术以及基于多点触摸的指点输入技术。然而此类受限视场显示设备将引起交互过程中的变视场及微目标问题,这些问题可能又将导致人机交互绩效的显著变化,进而影响其交互绩效的传统研究工具——Fitts’模型的可用性。通过人机交互实验,分别针对变视场条件及微目标条件对基于指点交互的人机绩效进行了定量分析,并基于此对Fitts’模型在移动与可穿戴计算中的可用性进行了研究。结果表明传统 Fitts’模型不能适用于显示     

菜单点击绩效模型的建立与验证

为使研究人员能快速对交互系统的菜单设计进行评估,基于Fitts’定律和操纵定律,提出一个预测菜单点击绩效的模型,并用实验验证该模型的有效性。实验分为2个阶段,第1阶段计算模型中的系数值,第2阶段利用该系数值进行实验数据分析。实验结果表明,该模型预测得到的绩效数据与实验测试得到的绩效数据非常接近,两者相关性为0.959,可见其是有效的。     

基于EOG眼电信号的机器人三维定位

在控制机器人的各种方法中,采用生物电信号控制机器人的研究发展非常迅速,成为二十一世纪最热门的研究课题。眼电图EOG(electro-oculography)方法是目前唯一一种信号产生于生物电的眼运动记录技术。本文在对EOG的产生原理及扫视信号提取的方法进行分析的基础上,利用EOG信号提取侧、俯平面的视角变化来实现对机器人进行三维空间移动定位,最后通过仿真实验对整个移动定位控制的有效性进行了验证。     

用异质迁移学习构建跨被试脑电情感模型

由于脑电信号的个体差异性和非平稳特性对情感模型性能产生影响,如何构建跨被试脑电情感模型是情感脑-机接口领域的一个重要研究方向.本文提出一种新的从眼睛的扫视轨迹进行知识迁移的异质迁移学习方法,以提升跨被试脑电情感模型的性能.该方法的主要神经生理学依据是,被试的视觉注视诱发了大脑特定的神经活动,而这些神经活动产生的脑电信号可以为情绪识别提供重要的情境线索.为了量化不同被试之间的域差异,我们引入了基于扫视轨迹和基于脑电信号的核矩阵,并提出了改进的直推式参数迁移学习算法,以实现跨被试脑电情感模型的构建.该方法与传统方法相比,具有两个优点:一是利用了目标被试容易获取的眼动追踪数据进行被试迁移,二是在目标被试只有眼动追踪数据的情况下,仍然能够从其他被试的历史数据中学到脑电信号的情绪类别判别信息.为了验证所提方法的有效性,我们对本文提出的方法与已有的迁移方法在三类情绪识别的脑电和眼动数据集上进行了系统的对比实验研究.实验结果表明,基于眼动轨迹的迁移模型取得了与基于脑电信号的迁移模型相当的识别性能.相对于传统的通用分类器50.46%的平均准确率,基于眼动轨迹的迁移模型的平均准确率达到了69.72%.     

一种基于视频数据的服装显著性预测方法

人眼视觉注意机制表明当人眼观察目标时,注意力只会放在少数感兴趣的区域, 而自动忽略视野中大部分不感兴趣的其他区域。研究人类视觉注意机制,并构建有效的服装显 著性预测模型,可在后期用于指导更加逼真有效的服装运动建模,提高模拟效率。为此,对着 装人体运动视频数据进行分析,构造了种类多样的视频样本,并利用眼动技术采集真实人眼的 注视数据,采用高斯卷积生成视频帧的显著图作为训练模型所需的 Ground-truth。在进行视频特 征提取时,结合了底层图像特征、高层语义特征以及运动特征,共同构造特征向量和标签,并 通过支持向量机(SVM)训练得到基于服装视频的显著性预测模型。通过实验验证,该方法的性 能在服装显著性预测时,优于传统的显著性预测算法,具有一定的鲁棒性。     

手机三维菜单绩效预测模型

菜单是手机界面的重要交互部件,手机功能增加所带来的菜单规模增大与手机小屏幕形成日益突出的矛盾.三维界面技术可以提高界面信息容量,因此,在手机上引入三维菜单概念是一个值得研究的课题.相应地,需要解决手机三维菜单用户操作绩效的评估问题.模型预测评估法能使研究人员和设计人员快速和以较低成本对用户界面进行评估.因此,基于Fitts定律和Hick-Hyman定律,建立了预测评估手机三维菜单操作绩效的定量模型.通过实验检验了模型的有效性,并将其与相关模型进行了对比分析.实验结果表明,实验得到的数据与该模型预测数据吻合较好,并且与相关模型相比该模型预测数据与实验数据的相关度最高.     

基于视线跟踪的智能界面实现机制研究

针对传统用户界面难以满足普适计算发展的需求,提出一种基于视线跟踪的智能界面解决方案。首先,以视觉注意力选择机制为理论基础,对智能界面交互框架中用户、界面和系统三要素进行统一描述和说明;然后,以三要素的映射关系为研究依据,采用模糊聚类方法来计算用户对界面对象的注意程度值,并使用视觉注意分配策略来预测用户对界面对象的兴趣程度;最后,设计相关实验来验证智能界面实现机制的有效性。实验结果表明,智能界面预测用户决策意图的准确率高达85%,是一种能够主动标注用户兴趣目标的智能界面可选方案。     

目标颜色对视线交互的影响研究

随着眼动跟踪技术的日益成熟,面向终端用户的视线输入产品问世,视线交互(Gaze-based Interaction)的实用性越来越高。然而,由于眼睛并不是与生俱来的控制器官,用户界面中无论动态或静态的各种视觉反馈,在视线交互过程中都可能干扰用户的眼动,从而影响视线输入(视点坐标)。因此,通过两个视线点击(Eye Pointing)实验,从视点的空间分布特征和视线交互的人机工效两个方面,系统地评估了目标颜色因素对视线交互的影响。结果表明,目标颜色这类静态视觉反馈虽然不影响用户凝视目标时视点坐标的稳定性,但的确会对用户的眼动扫视过程造成显著影响,从而影响视线点击任务的人机工效。特别是在视线移动距离较长的情况下,这种影响更为明显。     

基于视线碰撞检测算法的研究

碰撞检测能增强场景漫游中的真实感,在Vega中由于对自定义的运动模型根本起不到实质的作用,因此本文提出了基于视线的碰撞检测算法。借助简化的OBB包围盒来简化碰撞的模型,以提高碰撞检测的效率。经实验验证。该检测方法简单、精确,检测速度快。能够满足大范围场景中实时交互的要求。     

Control of a Camera for Active Vision: Foveal Vision,Smooth Tracking and Saccade

Several characteristics of the human oculomotor system have been suggested to be useful also for active vision mechanisms. Among others, foveal vision and a tracking scheme based on two different modes, called smooth pursuit and saccade have often been postulated or implemented. The purpose of this paper is to formulate a setup in which the benefit of implementing these schemes can be evaluated in a systematic manner, based on control considerations but incorporating image processing constraints. First, the advantage of using foveal vision is evaluated by computing the size of the foveal window which will allow tracking of the largest possible class of signals. By using linear optimal control theory, this problem can be formulated as a one-variable maximization.Second, foveal vision leads naturally to smooth pursuit, defined as the performance that can be achieved by the controller resulting in the optimal size of the foveal window. This controller is relatively simple (i.e., linear, time-invariant) as is to be expected for this control loop.Finally, when smooth pursuit fails a corrective action must be performed to re-center the target on the fovea. Recent results in linear optimal control, provide the necessary tools for addressing this challenging problem in a systematic manner.     

Facilitation of reaction times with GAP paradigm: comparison of manual and saccadic responses

Manual and saccadic reaction times (RTs) were measured to peripheral target onsets. Previous researchers reported marked decrement in saccadic latencies when the central fixation mark offset preceded the target onset by a short interval (a gap paradigm). The first experiment ascertained whether a similar RT facilitation would occur with a manual RT task. It was found that, in line with previous studies, a majority of saccades was less than 150 ms when a gap of 200 ms was inserted between the fixation offset and the target onset. These short latency saccades were executed virtually without error. Manual RTs were also facilitated, but the amount of facilitation was modest, and it was bargained for at the expense of increased errors.

To compare these two response modes under the gap paradigm, two additional experiments were conducted. First, to check the possibility that the facilitation of manual RTs was due to the prolonged experience with the gap paradigm, 36 naive subjects were recruited, and their manual RTs were measured under one of two gap durations (100 or 200 ms). Both gap durations were successful in bringing about RT facilitation, suggesting that naive subjects could utilize the gap paradigm to speed up their responses. The gap durations of 100 and 200 ms were equally effective in the facilitation of RTs.

In the final experiment, three subjects were observed in manual and saccadic RT tasks under 13 gap-overlap intervals (— 1000 to + 1000ms, of which a negative sign indicates a delayed fixation mark offset relative to target onset or overlap condition). Both saccadic and manual RTs were shortened in the gap range 100-300 ms, while they were increased under the short (less than 300 ms) overlap condition. These effects were more conspicuous for the saccade. Prolonged fixation mark presentation (overlaps of more than 500 ms) caused delayed response initiations only for the saccade.     

Effects of anomalous characters and small stroke omissions on eye movements during the reading of Chinese sentences

We investigated the influence of typographical errors (typos) on eye movements and word recognition in Chinese reading. Participants' eye movements were tracked as they read sentences in which the target words were presented (1) normally, (2) with the initial stroke of the first characters removed (the omitted stroke condition) or (3) the first characters replaced by anomalous characters (the anomalous character condition). The results indicated that anomalous characters caused longer fixation durations and shorter outgoing forward saccade lengths than the correct words. This finding is consistent with the prediction of the theory of the processing-based strategy. Additionally, anomalous characters strongly disrupted lexical processing and whole sentence comprehension, but small stroke omissions did not. Implications of the effect of processing difficulty on forward saccade targeting for models of eye movement control during Chinese reading are discussed.     

What makes an automated teller machine usable by blind users?

The present study examines changes in a variety of oculomotoric variables as a function of increasing sleepiness in 129 participants, who have been passed through a broad range of subjective alertness. Up to now, spontaneous eye blinks are the most promising biosignal for in-car sleepiness warnings. Reviewing the current literature on eye movements and fatigue, experimental data are provided including additional indicative oculomotoric parameters; inter-individual differences in the experiments were also assessed. Here, self-rated alertness decreased over six steps on average and proved itself a reliable measurement. Regarding oculomotoric parameters, blink duration, delay of lid reopening, blink interval and standardised lid closure speed were identified as the best indicators of subjective as well as objective sleepiness. Saccadic parameters and fixation durations also showed specific changes with increasing sleepiness. Substantial inter-individual differences in all of these variables were illustrated. Oculomotoric parameters were linked to three different components of sleepiness while driving: a) deactivation; b) decreasing attention, resulting in disinhibition of spontaneous blinks and reflexive saccades; c) increasing attempts of self-activation. Finally, implications for the development of drowsiness detection devices were discussed.     

Ocular movements under taskload manipulations: Influence of geometry on saccades in air traffic control simulated tasks

Traffic geometry is a factor that contributes to cognitive complexity in air traffic control. In conflict‐detection tasks, geometry can affect the attentional effort necessary to correctly perceive and interpret the situation; online measures of situational workload are therefore highly desirable. In this study, we explored whether saccadic movements vary with changes in geometry. We created simple scenarios with two aircraft and simulated a conflict detection task. Independent variables were the conflict angle and the distance to convergence point. We hypothesized lower saccadic peak velocity (and longer duration) for increasing complexity, that is, for increasing conflict angles and for different distances to convergence point. Response times varied accordingly with task complexity. Concerning saccades, there was a decrease of peak velocity (and a related increase of duration) for increased geometry complexity for large saccades (>15°). The data therefore suggest that geometry is able to influence “reaching” saccades and not “fixation” saccades. © 2011 Wiley Periodicals, Inc.     

A REQUISITELY HOLISTIC VIEW OF HUMAN RESOURCES MANAGEMENT IN INNOVATIVE ENTERPRISES

ABSTRACT

This paper first briefly presents the environment and challenges that companies will encounter in the current decade, enhancing innovative society and business style. On this basis, the authors investigate the challenges that will impact the implementation of human resources management in companies as a cybernetic system. Because there exists a two-way link between the companies and the environment, this contribution also illustrates the link in the other direction and shows how a company can gain competitive advantage by effective human resources management. The point is that companies are moving from being knowledge-based to being creativity-based to be sustainable and innovative businesses. They need requisite holism in their conception and cybernetics in their action to succeed in this complex move. We suggest a cybernetic model aimed at meeting this need.     

基于CornerNet-Saccade的手部分割模型

手部分割技术受手部形态、分割背景等因素的影响,分割效率难以提高。在CornerNet-Saccade模型基础上构造一种基于扫视机制的分割模型。通过模拟人眼观察物体时先扫视再仔细观察的行为特征,降低待处理图像的像素数量并在初步判断手部位置后将掩码分支添加到不同尺度特征图中,完成精细分割任务。在此基础上,引入线性瓶颈结构完成模型轻量化操作以降低模型复杂度。实验结果表明,该模型在Egohands数据集上平均交并比高达88.4%,优于RefinNet、U-Net等主流模型,轻量化处理后其平均交并比虽降低了2.2个百分点,但参数量仅为原模型的44.9%。     

Visual and memory search in complex environments: determinants of eye movements and search performance

Previous research on visual and memory search revealed various top down and bottom up factors influencing performance. However, utilising abstract stimuli (e.g. geometrical shapes or letters) and focussing on individual factors has often limited the applicability of research findings. Two experiments were designed to analyse which attributes of a product facilitate search in an applied environment. Participants scanned displays containing juice packages while their eye movements were recorded. The familiarity, saliency, and position of search targets were systematically varied. Experiment 1 involved a visual search task, whereas Experiment 2 focussed on memory search. The results showed that bottom up (target saliency) and top down (target familiarity) factors strongly interacted. Overt visual attention was influenced by cultural habits, purposes, and current task demands. The results provide a solid database for assessing the impact and interplay of fundamental top down and bottom up determinants of search processes in applied fields of psychology. Practitioner Summary: Our study demonstrates how a product (or a visual item in general) needs to be designed and placed to ensure that it can be found effectively and efficiently within complex environments. Corresponding product design should result in faster and more accurate visual and memory based search processes.