盲人数据库系统的实现

一种专门为盲人设计的数据库系统,该系统通过语音引导、盲文输入实现数据库创建、删除及数据维护等功能,并对软件的开发环境、关键技术进行了分析.     

适合于盲人使用的信息输入方法的研究与实现

提出了Braille立体盲文的平面化输入方法,研究了非特定人孤立词语音识别技术,建立了一种新型盲人专用信息输入方法。该方法将Braille立体盲文抽象为平面符号,实现盲文的平面化输入及识别,并将连续隐马尔可夫模型的语音识别算法应用于非特定人孤立词语音系统中,利用嵌入式DSP系统实现了语音与盲文信号采集、处理和识别,为盲人信息输入提供了新的途径。实验结果表明,该系统语音指令识别率＞92％,盲文字符识别率＞91％。     

国内第一款盲人用计算机在黑龙江问世

操作使用计算机对于大多数盲人都是难以想象的，日前黑龙江省开发出国内第一款盲用计算机——同创蓝天盲用计算机，使得盲人能够通过操作计算机完成上网学习、工作和娱乐。     

基于Android平台的盲人手机系统设计与开发

人们生活中的绝大部分信息都是通过视觉获得的,所以盲人能够从外界获取的信息量很少,但这并不能阻止他们努力提高生活质量的渴望。智能手机的快速发展给盲人提供了前所未有的机遇。开发盲人手机具有极大的应用价值。该文主要介绍了在Android平台上设计和实现的一款盲人手机系统,该系统使用了语音识别、语音合成及Web Service等相关技术,实现了语音拨打电话、语音接听电话、语音发送短信、语音播报来电短信、语音报时、语音播报日期和语音播报天气等功能,并能在Android手机中稳定运行,方便盲人使用手机,具有较高的实用价值。     

基于Android平台的盲人手机系统设计与开发

人们生活中的绝大部分信息都是通过视觉获得的,所以盲人能够从外界获取的信息量很少,但这并不能阻止他们努力提高生活质量的渴望。智能手机的快速发展给盲人提供了前所未有的机遇。开发盲人手机具有极大的应用价值。该文主要介绍了在Android平台上设计和实现的一款盲人手机系统,该系统使用了语音识别、语音合成及Web Service等相关技术,实现了语音拨打电话、语音接听电话、语音发送短信、语音播报来电短信、语音报时、语音播报日期和语音播报天气等功能,并能在Android手机中稳定运行,方便盲人使用手机,具有较高的实用价值。     

汉语盲人电脑软件的开发和研究

本文介绍了盲文的历史沿革及福音盲文软件概况，并提出一种适合中国盲人操作的文字处理，有声浏览器、有声电子邮件和有声数据库系统的开发与实现方法，对邮件处理与管理、盲用有声数据库的系统模块作了介绍。     

功能智能盲人拐杖助手的开发与设计

针对市场上提供盲人使用的拐杖结构简单,功能单一,无法实现较好导盲效果的缺点,本文以单片机IAP15F2K61S2为主控件,设计了一款具有GPS定位、GSM手机通信、超声波测障、语音提示等功能的多功能智能盲人拐杖助手;该拐杖可以对前方障碍物实时探知报警,具有语音控制接打电话的功能,使盲人随时可以方面的和家人、朋友沟通,还可以实现将短信内容用语音的方式播报出来,使盲人随时知道自己当前的位置、时间、天气信息等语音提醒,特别突出的是家人、朋友可以随时通过GPS掌握盲人的具体位置,而且当盲人发生意外时只需按一下按键就会自动拨打紧急电话求助家人,家人也可以随时监听到盲人周围的环境声音,达到既方便又安全出行的目的.该设计功能齐全、操作简单、成本较低,具有很强的实用性和推广价值.     

基于单片机无线通信技术的盲人交通提示系统设计

为解决盲人交通问题,研究开发了一种新型交通语音提示系统。采用AT89S51单片机结合无线射频芯片NRF401的方法,为盲人设计一套便携式的信号发送/接收终端,以半双工通信的方式和ISD1420语音录放模块来共同实现交通灯信号的无线语音提示功能,性能比现有语音提示系统有了较大提高。     

“虚拟再现式”盲文指套

盲文是盲人与社会沟通的重要桥梁,是帮助盲人融入正常生活的重要工具。随着盲人的数量逐年增多,盲文学习的需求也越来越大。针对盲人学习盲文的必要性、盲文教师的短缺以及现有盲文翻译器不具备盲文学习功能的现状,设计了一款通过触听结合方式帮助盲人阅读和学习盲文的工具。使用者通过手机APP向盲文指套发送一篇文章后,戴上指套并接触任意一个水平平台(例如桌面)时开始移动,即可逐个阅读指套呈现的盲文,即虚拟再现一本盲文书供盲人摸读,同时与手环连接的蓝牙耳机还会发出对应盲文的读音。     

Windows Mobile平台下的盲人导航软件系统开发

针对传统导航产品基于视觉的功能设计和人机界面不便盲人使用的弱点,在运行Windows Mobile系统的智能手机平台上,结合全球卫星定位系统（GPS）和地理信息系统（GIS）,开发了适合盲人出行使用的导航软件系统。通过研发定制盲人专用地图数据源,改进迪克斯特拉寻径算法,完成适于盲人行走的最适路径规划;系统具备路线定制、短信求助和周边搜索等针对盲人用户的功能,实现了语音、按键等人机交互方式。     

Audemes at work: Investigating features of non-speech sounds to maximize content recognition

To access interactive systems, blind users can leverage their auditory senses by using non-speech sounds. The structure of existing non-speech sounds, however, is geared toward conveying atomic operations at the user interface (e.g., opening a file) rather than evoking broader, theme-based content typical of educational material (e.g., an historical event). To address this problem, we investigate audemes, a new category of non-speech sounds whose semiotic structure and flexibility open new horizons for the aural interaction with content-rich applications. Three experiments with blind participants examined the attributes of an audeme that most facilitate the accurate recognition of their meaning. A sequential concatenation of different sound types (music, sound effect) yielded the highest meaning recognition, whereas an overlapping arrangement of sounds of the same type (music, music) yielded the lowest meaning recognition. We discuss seven guidelines to design well-formed audemes.     

Multiple spatial sounds in hierarchical menu navigation for visually impaired computer users

This paper describes a user study on the benefits and drawbacks of simultaneous spatial sounds in auditory interfaces for visually impaired and blind computer users. Two different auditory interfaces in spatial and non-spatial condition were proposed to represent the hierarchical menu structure of a simple word processing application. In the horizontal interface, the sound sources or the menu items were located in the horizontal plane on a virtual ring surrounding the user’s head, while the sound sources in the vertical interface were aligned one above the other in front of the user. In the vertical interface, the central pitch of the sound sources at different elevations was changed in order to improve the otherwise relatively low localization performance in the vertical dimension. The interaction with the interfaces was based on a standard computer keyboard for input and a pair of studio headphones for output. Twelve blind or visually impaired test subjects were asked to perform ten different word processing tasks within four experiment conditions. Task completion times, navigation performance, overall satisfaction and cognitive workload were evaluated. The initial hypothesis, i.e. that the spatial auditory interfaces with multiple simultaneous sounds should prove to be faster and more efficient than non-spatial ones, was not confirmed. On the contrary—spatial auditory interfaces proved to be significantly slower due to the high cognitive workload and temporal demand. The majority of users did in fact finish tasks with less navigation and key pressing; however, they required much more time. They reported the spatial auditory interfaces to be hard to use for a longer period of time due to the high temporal and mental demand, especially with regards to the comprehension of multiple simultaneous sounds. The comparison between the horizontal and vertical interface showed no significant differences between the two. It is important to point out that all participants were novice users of the system; therefore it is possible that the overall performance could change with a more extensive use of the interfaces and an increased number of trials or experiments sets. Our interviews with visually impaired and blind computer users showed that they are used to sharing their auditory channel in order to perform multiple simultaneous tasks such as listening to the radio, talking to somebody, using the computer, etc. As the perception of multiple simultaneous sounds requires the entire capacity of the auditory channel and total concentration of the listener, it does therefore not enable such multitasking.     

Designing a Telephone-Based Interface for a Home Automation System

User-interface design lacks expertise in designing nonvisual user interfaces. This is surprising as there are various domains where auditory interfaces have already been proved to be helpful, such as railway information services and reading support for blind persons.

We present a case study concerning the design of a telephone-based interface (TBI). It was realized within the development process of an interaction concept for a modular home automation system. The design was based on requirements gathered in user focus groups and on general guidelines for the design of TBIs. The TBI's evaluation revealed some minor (i.e., easily solved) usability problems. Questionnaires showed a positive ergonomic quality as well as a positive overall appeal. Interestingly, the evaluation indicates a potential to improve hedonic quality (i.e., non-task-related quality aspects). It may be induced by the addition of nonspeech sounds, thereby enriching user experience.     

有限流通期的无可信第三方离线电子现金系统

结合Camenisch等的加标记跟踪及证明方法和Abe等部分盲签名方案，提出了一个无可信第三方的离线电子现金系统，并提出了电子现金有效期的概念。方案中银行只在需要跟踪时要求用户打开标记，从而进行用户和钱币的跟踪，因此简便实用地解决了无可信第三方情况下电子现金匿名性控制问题。该系统具有计算量小、在线处理效率高的特点，且能有效地控制银行付款说明数据库的大小。     

基于ACM在线评测推荐系统模型研究

针对目前用户对在线程序评判系统选题目盲目问题,建立了ACM在线评测推荐系统模型。通过定义题目的难度系数及所属知识点类型,对用户所做题目运用web数据挖掘技术,进行归类挖掘,然后运用基本推荐策略将题目推荐给用户,通过此平台用户登录在线评判系统网站不再盲目选题。     

无人机空中通信数据库信息盲检索系统设计

对无人机空中通信数据库信息盲检索系统进行设计,能够有效解决传统盲检索系统存在的数据召回率低、细粒度差、检索准确度低及实时性差等问题。先给出无人机空中通信数据库信息盲检索系统的总体架构设计,通过对存储器结构进行改进,实现系统硬件部分的优化;采用Java语言和嵌入式开发库设计可视化检索页面,选取检索信息,增设中间件搜索功能,通过盲检索功能的实现,完成系统软件部分的开发,从而设计出无人机空中通信数据库信息盲检索系统。实验结果表明,该系统数据召回率高,细粒度强,检索准确度高,实时性好。     

SoundWorks: an object-oriented distributed system for digital sound

SoundWorks, an object-oriented distributed system that lets users interactively manipulate sound through a graphical interface, is discussed. The system handles digitally sampled sounds as well as those generated by software and digital signal processing hardware. An overview of the different types of sounds and window interfaces provided by SoundWorks and of the operations that modify these sounds is presented. The high-level architecture and the design of the SoundWorks system the protocol defined between the user interface code and client application, and the sound kernel specification that manages sounds and lines, performs operations on sounds, and interfaces to the digital hardware are described. The NEWS application programming environment, which provided the necessary primitive graphic items for a graphical window-based interface and offered an object-oriented approach for development of the SoundWorks system, is also discussed     

A null space method for over-complete blind source separation

In blind source separation, there are M sources that produce sounds independently and continuously over time. These sounds are then recorded by m receivers. The sound recorded by each receiver at each time point is a linear superposition of the sounds produced by the M sources at the same time point. The problem of blind source separation is to recover the sounds of the sources from the sounds recorded by the receivers, without knowledge of the m×M mixing matrix that transforms the sounds of the sources to the sounds of the receivers at each time point. Over-complete separation refers to the situation where the number of sources M is greater than the number of receivers m, so that the source sounds cannot be uniquely solved from the receiver sounds even if the mixing matrix is known. In this paper, we propose a null space representation for the over-complete blind source separation problem. This representation explicitly identifies the solution space of the source sounds in terms of the null space of the mixing matrix using singular value decomposition. Under this representation, the problem can be posed in the framework of Bayesian latent variable model, where the mixing matrix and the source sounds can be inferred based on their posterior distributions. We then propose a null space algorithm for Markov chain Monte Carlo posterior sampling. We illustrate the algorithm using several examples under two different statistical assumptions about the independent source sounds. The blind source separation problem is mathematically equivalent to the independent component analysis problem. So our method can be equally applied to over-complete independent component analysis for unsupervised learning of high-dimensional data.     

General purpose schedulers for database systems

Summary A family of simple models for database systems is defined, where a system is composed of a scheduler, a data manager and several user transactions. The basic correctness criterion for such systems is taken to be consistency preservation. The central notion of the paper is that of a general purpose scheduler, a database system scheduler that is blind to the semantics of transactions and integrity assertions. Consistency preservation of a database system is shown to be precisely equivalent to a restriction on the output of a general purpose scheduler GPS, called weak serializability. That is, any database system using GPS will preserve consistency iff the output of GPS is always weakly serializable. This establishes a tight connection between database system correctness and scheduler behavior. Also, aspects of restart facilities and predeclared data accesses are discussed. Finally, several examples of schedulers correct with respect to weak serializability are presented.     

A Navigation Aid for Blind People

This paper presents a navigation aid for the blind based on a microcontroller with synthetic speech output. The system consists of two vibrators, two ultrasonic sensors mounted on the user??s shoulders and another one integrated into the cane. It is able to give information to the blind about urban walking routes and to provide real-time information on the distance of over-hanging obstacles within 6 m along the travel path ahead of the user. The suggested system can then sense the surrounding environment via sonar sensors and sending vibro-tactile feedback to the user of the position of the closest obstacles in range. For the ultrasonic cane, it is used to detect any obstacle on the ground. Experimental results show the effectiveness of the proposed system for blind navigation.