基于深度Q网络的人群疏散机器人运动规划算法

针对公共场合密集人群在紧急情况下疏散的危险性和效果不理想的问题，提出一种基于深度Q网络（DQN）的人群疏散机器人的运动规划算法。首先通过在原始的社会力模型中加入人机作用力构建出人机社会力模型，从而利用机器人对行人的作用力来影响人群的运动状态；然后基于DQN设计机器人运动规划算法，将原始行人运动状态的图像输入该网络并输出机器人的运动行为，在这个过程中将设计的奖励函数反馈给网络使机器人能够在"环境-行为-奖励"的闭环过程中自主学习；最后经过多次迭代，机器人能够学习在不同初始位置下的最优运动策略，最大限度地提高总疏散人数。在构建的仿真环境里对算法进行训练和评估。实验结果表明，与无机器人的人群疏散算法相比，基于DQN的人群疏散机器人运动规划算法使机器人在三种不同初始位置下将人群疏散效率分别增加了16.41%、10.69%和21.76%，说明该算法能够明显提高单位时间内人群疏散的数量，具有灵活性和有效性。     

巧用MSN安全版 轻松实现账号“双开”

MSN是我们工作必备的即时通讯工具,不过,由于面对的人群不同.笔者和很多朋友一样,也同时申请了多个账号,如和客户厂商沟通的、与亲朋好友交流的、和老同学、老伙伴联系的,等等.然而和QQ软件支持同时"多开"不同,MSN软件在此前的版本中,一直不能实现"双开",令很多用户大感郁闷.于是,正是充分考虑到用户的实际需要,在MSN最新的"安全版"中,这一功能得以实现.     

频域基于灰度共生矩阵的人群密度估计

人群密度估计对于大型公共设施的设计和人群的安全十分重要.本文提出了一种基于二维快速傅立叶变换和灰度共生矩阵的人群密度特征提取方法.主要思想是依据不同密度的人群图像在其频谱图上的不同,将频谱图视为纹理图像,利用纹理分析的方法提取能够表现这些不同的纹理特征.进而利用Adaboost实现人群密度级别的分类.实验结果表明本文提出的方法在具有不逊于其他算法的准确率的情况下,计算速度明显提高.     

基于非最大抑制聚类的视频人数估测方法

对于基准背景已知的固定场景,提出估测人数的四步框架,相比2010年D.Conte等的结果显著提高远距离人群的估测精度.精度提高的主要原因在于"非最大抑制聚类",这种基于密度的聚类方法对不同拍摄距离的人群采取不同的聚类标准,避免类过大造成的后续问题.PETS2010数据库的实验表明,远距离高密度人群因被分为多类,估测精度明显提高.     

职场动力 商旅活力 联想扬天笔记本火热促销

时至年中,中小企业进入了业务发展的活跃阶段,对于移动办公的需求也随之增加。由于不同级别员工对商务笔记本的要求有着明显的差别,中小企业主在更新IT设备时通常会寻求差异化采购。针对这一需求,联想扬天面向企业中的不同层级人群展开了以"职场动力、商旅活力"为主题的促销活动。     

基于群体性行为模型的人群分析及其应用

基于视频分析的人群监控,涉及到获取人群行为和数量,这在智能监控领域具有重要的现实价值。本文建立基于运动特征的群体性行为模型,挖掘复杂人群场景中的群体行为,用于人群行为和数量的分析。群体性行为模型是一种主题模型（LDA）,通过样本学习,可以获得描述不同群体行为的特征集,用于人群分析。实验中,将群体性行为模型应用于挖掘监控场景下的不同人群行为及其特征集,并使用人工神经网络完成人数统计,统计正确率达到92.35%。     

融入情绪模型的人群实时路径规划

目的 人群仿真中高效性和逼真性是群体路径规划的关键问题。已有人群路径规划算法忽略了人群情绪造成的路径选择差异,在大规模实时仿真中仍存在一定的局限性。方法 提出一种融入情绪模型的人群实时路径规划算法(EPP)。使用人格特征理论对人群的情绪进行建模并设定不同情绪所具有的路径选择偏好。在路径建模阶段,通过单次搜索建立全局有向导航图,确定全局层面的可行路径;在路径搜索阶段,提出以期望时间最短为原则的路径规划目标函数,采用局部搜索策略为个体实时规划一条最优或次优的路径。结果 EPP算法可有效地仿真不同场景下大规模人群的路径选择现象;与已有工作的仿真效果和量化指标对比说明了该算法的有效性和高效性;通过不同情绪状态下人群路径选择差异的讨论以及在不同人群运动模型的兼容性实验进一步说明了该算法的健壮性。结论 本文算法具有良好的高效性和健壮性,适用于不同场景下大规模人群路径规划的相关应用。     

支持跨平台的实时人群运动仿真系统

实时人群运动仿真系统通过虚拟现实技术,可在计算机中交互式地显示人群在指定场景中的运动状况.通过对人群设置不同的全局运动路径,可以模拟人群的不同行为,例如人群的集会、疏散、逃生等情况.故该技术可应用于应急疏散演练以减少事故的伤害甚至能发现并解决建筑在设计时可能存在的安全隐患等.目前,常见的人群运动仿真系统往往只能在单一操作系统下执行.随着计算机硬件和移动设备的发展,跨平台的仿真甚至在移动设备上进行人群仿真成为新的需求.本文提出了跨平台的实时人群运动仿真系统的系统架构,通过解析并处理C3D文件实现了人体动作,并通过Mono Game平台实现了跨平台的实时人群运动仿真.     

GoogleGroup:互动学习和专业交流的教师社区建设——以生物教学茶吧为例

"生物教学茶吧"的会员多是一线生物教师和教育工作者,还有部分对生物教学感兴趣的研究生。目前,生物教学茶吧已经与"教育大发现"、"淄博信息技术学科教师自生长学习社区"、"Edu2.0"等不同群组间建立联系,从而为成员进一步扩展网络圈子以及和不同特质人群对话提供环境。茶吧进一步发展的设想是继续进行群组推广工作、扶植新手、组建团队、引导讨论和合作、管理和传播群体知识、构建社区文化,从而营造一个能够不断螺旋上升发展的生物教师专业成长社区。以下,将以生物教学茶吧创建为例,介绍基于GoogleGroup建设的教师学习社区,在不同阶段所遇到的主要问题和应对处理方法,对实践有参考作用。     

基于视觉注意力机制的人群密度估计方法

针对人群图像中尺度变化大及现有密度估计网络泛化性能差的问题,提出一种基于视觉注意力机制的人群密度估计方法。该网络模型基于VGG-16网络,由空间注意力模块(Spatial Attention Module, SAM)、全局注意力模块(Global Attention Module, GAM)及融合模块(Fusion Module, FM)等几个模块组成,通过在网络不同层级中引入注意力机制来选择性地增强网络的功能,提高多尺度级联的有效性。设计一个弱监督学习来扩展提出的密度估计网络,使人群密度估计模型可以适应不同的场景和数据集。实验结果表明,该方法对不同尺度、不同场景下的人群密度图像都有很好的适用性和准确性,算法性能也优于现有的人群密度估计算法。     

Early user involvement in the development of information technology-related products for older people

The UTOPIA project (Usable Technology for Older People—Inclusive and Appropriate) is focused on developing effective methods for the early involvement of older people in the development of information technology-related products for people aged 60 and over, and on providing industry with tools to assist in the development of information technology products for such older people. An essential part of this methodology is building a diverse user base, forming a long-lasting partnership with older people, and developing approaches for effective interaction with this target user group. Our experiences with eliciting information from groups of older people about technology is described, together with a report on seminars for Scottish industry designed to raise an awareness of these issues.     

Introducing the Internet to the over-60s: Developing an email system for older novice computer users

Contemporary technology offers many benefits to older people, but these are often rendered inaccessible through poor software design. As the Internet increasingly becomes a source of information and services it is vital to ensure that older people can access these resources. As part of project funded by the UK government, a multi-disciplinary team set out to develop usable software that would help to introduce older people to the Internet. The first step was to develop an email system for older people with no experience of Internet use. The project was intended to show that it is possible to design usable technology for this group and to explore some of the issues involved in doing so. Design and technical challenges necessitated various tradeoffs. The system produced demonstrated the success of the design decisions: it was significantly easier to use than, and preferred to, a commercial equivalent by a group of older people with no experience of Internet use.     

Painting the ideal home: using art to express visions of technologically supported independent living for older people in north-east England

This paper describes the investigation of the development of future technological products to support older people in everyday living through the agency of a community art group. Recent research has identified a number of challenges facing designers seeking to use traditional participatory design approaches to gather technology requirements data from older people. Here, a project is described that sought to get a group of older people to think creatively about their needs and desires for technological support through the medium of paint. The artistic expression technique described in this article allowed the identification of issues that had also been found by previous research that used a range of different techniques. This indicates that the approach shows promise, as it allows information to be gathered in an environment that is comfortable and familiar using methods already known by the participants and which they find enjoyable. It provides a complement (or possible alternative) to standard protocols and has the potential benefit of extracting even richer information as the primary task for participants is enjoyable in its own right and is not associated with an interrogative process. Furthermore, it is argued that some of the key risks of traditional approaches are lessened or removed by the naturalistic setting of this approach.

Self-reported use of ICT (Information and communication technology) uptake in 2002 and discomfort amongst Finns aged 45-66

In recent years the use of new technical equipment and the Internet by middle-aged people has increased. This paper presents middle-aged people’s (45 years old or older) usage of new technical equipment and analyses how their (2704 persons) symptoms are associated with the equipment. Over 70% of Finland’s middle-aged population use mobile phones daily and less than 30% use desktop computers at leisure. For example, over 80% of middle-aged people had sometimes or often experienced pain, numbness or aches in the neck and about 70% had aches in the hip and lower back. The use of new technical equipment among the group of people who are outside working life was smaller than the people’s usage in general. In the future, when new technical equipment is developed, it is important to take into account, that people (outside working life) do not use, e.g., the Internet as much as people in general. The working environment will be much more ergonomic also at home and the Internet services will be easy to use for almost everyone, even those who have little experience or knowledge of computers and the Internet.     

实时人数计数系统

描述一个实时在线人数计数系统,该系统采用检测加跟踪的方法来实现人数计数功能。在检测阶段,采用MBLBP（multi-scale block LBP）特征,从运动区域上检测出行人。该特征速度快,并且在归一化下,能够适应多尺度的应用;在跟踪阶段,通过一个概率模型,将对行人的跟踪转化为对特征点的跟踪,并且在将检测目标和跟踪目标进行一一对应时,进一步利用各个目标内的特征点来完成相应的操作。最后用实际中不同场景下的视频,对系统的性能进行测试,同时还在一段公开的视频上进行了测试,实验结果表明,该系统能够在不同场景下较准确地实现人数计数功能。     

基于改进Hough变换的电梯轿厢内人数统计算法

考虑电梯轿厢内人数的电梯群控调度算法,可以在有限的时间内,找到更优解,对电梯的调度具有重要意义。针对目前基于视觉的人数统计算法正确率不够稳定,速度较慢的问题,提出了一种基于改进Hough变换检测人头轮廓的电梯轿厢内人数统计算法。该算法将标准Hough变换检测圆时的三维空间转换为一维空间,利用圆的几何特性遍历图像数据,通过一维Hough变换进行半径累积,并和阈值进行比较来确定人头轮廓的半径和圆心。结果表明,和用Hough变换检测人头轮廓的传统方法相比,该算法具有速度快,正确率高,抗噪性能好等优点。     

Older people’s production and appropriation of digital videos: an ethnographic study

While most of today’s children, young people, and adults are both consumers and producers of digital content, very little is known about older people as digital content creators. Drawing on a three-year ethnographic study, this paper reports on the digital video production and appropriation of approximately 200 older people (aged 60–85). They generated 320 videos over the course of the study. We show their motivations for engaging in digital video production, discuss their planned video making, and highlight their creativity while editing videos. We show the different meanings they ascribed to digital videos in their social appropriation of these objects, the meaningful strategies they adopted to share videos, and the impact on their perceived wellbeing. Furthermore, we outline the solutions the participants developed to overcome or cope with interaction issues they faced over time. We argue that the results portray older people as active and creative makers of digital videos with current video capturing, editing, and sharing technologies. We contend that this portrayal both encourages us to re-consider how older people should be seen within human–computer interaction and helps to frame future research/design activities that bridge the grey digital divide.     

Support and information needs of older and disabled older people in the UK

The aim of this study was to determine the support and information needs of older and disabled older people in the UK. Following an initial literature survey, an examination of data on enquiries made by older people to information providers, and a series of focus groups, a questionnaire was developed for a nationwide survey. Over 1630 questionnaires were completed by disabled older clients of Day Care Centres and less frail older members of social clubs. Findings showed that there is a serious shortfall in the number of older people getting the practical support that they need, and the information that enables access to this support, compared to the number that actually need help. Substantial percentages of the survey respondents experienced difficulty with everyday tasks and with accessing the information they needed. Implications for formal sources of support and information are discussed.