Enabling entity discovery in indoor commercial environments without pre-deployed infrastructure

Finding entities of interest in indoor commercial places, such as the merchandise in supermarkets and shopping malls, is an essential issue for customers, especially when they are unfamiliar with an ad hoc indoor environment. This type of location-based indoor service requires comprehensive knowledge of indoor entities, including locations as well as their semantic information. However, the existing indoor localization approaches fail to directly localize these general entities without dedicated devices. This paper first focuses on the problem of discovering large-scale general entities of interest in indoor commercial spaces without pre-deployed infrastructure.We present a unique entity localization approach that leverages the localization results from multiple independent users to accurately determine the location of corresponding entities. Our key idea is to exploit the short-distance estimation with dead reckoning to guarantee the accuracy of entity localization. We develop a prototype system based on the crowdsourcing method, iScan, and test it in one of the biggest supermarkets in Changsha, China, to validate the performance of our design. Extensive experimental results show that our approach can achieve meter-level accuracy in a single day with 70 participants. Moreover, in a monthly evaluation with 500 effective participants, iScan discovered more than 200 entities and localized approximately 75% of them within 2 m.     

RFID-based indoor location tracking to ensure the safety of the elderly in smart home environments

In recent years, the number of elderly people living alone has grown rapidly. This increases the need for indoor healthcare services that help elderly residents live a safe and independent life. There has been increasing interest in indoor ubiquitous healthcare (U-Healthcare) applications that monitor the elderly unobtrusively via sensors and that warn them or healthcare providers of abnormal conditions. In U-Healthcare applications, automatically locating and tracking users who move around a building is a fundamental feature. Outdoor location sensing technologies such as the global positioning systems are not suitable for use in indoor environments, such as “smart home” applications, because their indoor-based location sensing lacks accuracy. This paper proposes an indoor U-Healthcare system that uses radio-frequency identification technology to accurately locate and track the elderly. The proposed system provides real-time monitoring of elderly people’s whereabouts. In addition, it analyzes their locations in association with time slots and the length of time they stay in the same place, thus inferring information such as movement patterns, ranges, and frequencies. This information is used to determine elderly people’s well-being and to warn family or healthcare workers of any potential problems. The proposed indoor U-Healthcare system improves the quality and convenience of care delivered to elderly people.     

Autonomous Landing of MAVs on an Arbitrarily Textured Landing Site Using Onboard Monocular Vision

This paper presents a novel solution for micro aerial vehicles (MAVs) to autonomously search for and land on an arbitrary landing site using real-time monocular vision. The autonomous MAV is provided with only one single reference image of the landing site with an unknown size before initiating this task. We extend a well-known monocular visual SLAM algorithm that enables autonomous navigation of the MAV in unknown environments, in order to search for such landing sites. Furthermore, a multi-scale ORB feature based method is implemented and integrated into the SLAM framework for landing site detection. We use a RANSAC-based method to locate the landing site within the map of the SLAM system, taking advantage of those map points associated with the detected landing site. We demonstrate the efficiency of the presented vision system in autonomous flights, both indoor and in challenging outdoor environment.     

基于改进双向测距到达时间差定位算法的超宽带定位系统

针对传统无线定位技术在室内定位精度不高的问题,设计实现了一种基于超宽带（UWB）技术的室内定位系统。首先,提出了定位服务器与移动端APP实时交互的系统结构,解决室内移动人员自主定位与导航的问题。其次,在双向测距（TWR）算法中增加一条无线电信息以减小时钟偏移引起的测距误差,从而提高算法性能。最后,将通过到达时间差（TDOA）定位算法得到的双曲面方程组进行线性化处理后结合Jacobi迭代法完成求解,避免了使用标准TDOA定位算法难以直接解算的情况。经测试,该系统在楼道房间等场景中能稳定工作且定位误差控制在30 cm以内,相比基于WiFi、蓝牙等技术的定位系统在定位精度上提高了10倍左右,能够满足在复杂室内环境中的精确移动定位需求。     

A novel acoustic indoor localization system employing CDMA

Nowadays outdoor location systems have been used extensively in all fields of human life from military applications to daily life. However, these systems cannot operate in indoor applications. Hence, this paper considers a novel indoor location system that aims to locate an object within an accuracy of about 2 cm using ordinary and inexpensive off-the-shelf devices and that was designed and tested in an office room to evaluate its performance.In order to compute the distance between the transducers (speakers) and object to be localized (microphone), time-of-arrival measurements of acoustic signals consisting of Binary Phase Shift Keying modulated Gold sequences are performed. This DS-CDMA scheme assures accurate distance measurements and provides immunity to noise and interference.Two methods have been proposed for location estimation. The first method takes the average of four location estimates obtained by trilateration technique. In the second method, only a single robust position estimate is obtained using three distances while the least reliable fourth distance measurement is not taken into account.The system?s performance is evaluated at positions from two height levels using system parameters determined by preliminary experiments. The precision distributions in the work area and the precision versus accuracy plots depict the system performance. The proposed system provides location estimates of better than 2 cm accuracy with 99% precision.     

Context-aware,self-scaling Fuzzy ArtMap for received signal strength based location systems

Location awareness is the key capability of mobile computing applications. Despite high demand, indoor location technologies have not become truly ubiquitous mainly due to their requirements of costly infrastructure and dedicated hardware components. Received signal strength (RSS) based location systems are poised to realize economical ubiquity as well as sufficient accuracy for variety of applications. Nevertheless high resolution RSS based location awareness requires tedious sensor data collection and training of classifier which lengthens location system development life cycle. We present a rapid development approach based on online and incremental learning method which significantly reduces development time while providing competitive accuracy in comparison with other methods. ConSelFAM (Context-aware, Self-scaling Fuzzy ArtMap) extends the Fuzzy ArtMap neural network system. It enables on the fly expansion and reconstruction of location systems which is not possible in previous systems.     

A Small and Lightweight Autonomous Laser Mapping System without GPS

Autonomous mapping systems execute multiple tasks that include navigation, location, and map generation via the collaborative work of multiple sensors. They are the object of a substantial research focus in the fields of robotics and remote sensing. Although the state‐of‐the‐art mobile mapping systems typically found in ready‐made vehicles or robots are reliable, they are rather large and heavy, their cost is high, and they generally use GPS and an inertial measurement unit to position, so their working environments are limited. After reviewing the current state of autonomous mapping systems, we describe the design and development of a small and lightweight autonomous mapping system (ASQ‐6DMapSys) without GPS, which incorporates low‐cost sensors and components. We describe the layout and selection strategy for sensors and other components in detail, and we present the design methodology for each subsystem. The ASQ‐6DMapSys employs a two‐dimensional (2D) lidar, an inclinometer, and two wheel encoders, which constitute a pose subsystem that uses extended Kalman filtering and simultaneous localization and mapping techniques to compute the pose of the vehicle body. A low‐cost 3D lidar that we developed is also installed on the vehicle body, and the resultant data are aligned with the corresponding pose data of the vehicle body to build a 3D point cloud that describes the global geometry of the environment. We designed and developed every subsystem of the ASQ‐6DMapSys, including the robot vehicle, so it will be easy to expand its functions in the future. The ASQ‐6DMapSys performs well in indoor, outdoor, and tunnel environments, and the experiments in different environments show that the ASQ‐6DMapSys is an effective, small, and lightweight autonomous mapping system with a high performance/price ratio.     

基于微信的考勤管理系统#br# 身份认证及位置识别方法的实现机制

介绍一种基于微信内嵌浏览器的身份认证与位置识别方法的实现机制,该机制利用微信OpenID和双向绑定Token这2种方式作为身份识别机制,以保证用户身份的有效性;采用AP信息识别和动态二维码进行定位,解决了手机地理位置信息在室内定位中存在的不足。该机制充分利用移动互联网技术和微信这一用户群体广泛的移动应用,具有实现简单、识别精确、用户使用便捷、跨平台兼容性强等特点,较生物识别技术等其他考勤管理技术方案,具有成本低廉、部署方便等优势。     

Providing location based information/advertising for existing mobile phone users

In the emerging world of m-commerce potential users consistently cite location based information as one of the emergent services that they would most likely utilise. However, solutions for obtaining the specific location of a mobile user predominately rely on the provision of additional hardware and/or software within either the mobile phone or system infrastructure. Further, these techniques are often inappropriate for indoor and highly urban environments, where they are often most useful, as the line of sight to the location measurement unit is often obscured resulting in inaccurate and unreliable positional information. In this paper we present a system that can be used with any current mobile phone system to provide location based information/advertisements to any mobile phone, equipped with Bluetooth technology, without any necessity of installing client side software. The system is readily deployable and can be used to provide systems such as location based information for tourist in cities or museums or indeed location based advertisements.     

Situation awareness measurement: a review of applicability for C4i environments

The construct of situation awareness (SA) has become a core theme within the human factors (HF) research community. Consequently, there have been numerous attempts to develop reliable and valid measures of SA but there is a lack of techniques developed specifically for the assessment of SA in command, control, communication, computers and intelligence (C4i) environments. During the design, development and evaluation of novel systems, technology and procedures, valid and reliable situation awareness measurement techniques are required for the assessment of individual and team SA, in order to determine the improvements (or in some cases decrements) resulting from proposed design and technological interventions. The paper presents a review of existing situation awareness measurement techniques for their suitability for use in the assessment of SA in C4i environments. Seventeen SA measures were evaluated against a set of HF methods criteria. It was concluded that current SA measurement techniques are inadequate by themselves for use in the assessment of SA in C4i environments, and a multiple-measure approach utilising different approaches is recommended.     

EDIPS: an Easy to Deploy Indoor Positioning System to support loosely coupled mobile work

Loosely coupled mobile work is characterized by nomadic workers collaborating in sporadically and on-demand ways. Supporting nomadic workers’ interactions requires knowing the location of the potential collaborator; therefore, indoor/outdoor positioning systems play a key role. Locating persons in outdoor environments is well addressed by Global Positioning Systems (GPS); however, for the indoor scenario, the solution is not so clear. Although several proposals for indoor positioning have been reported in the literature, most of them demand important setup efforts. This article presents the Easy to Deploy Indoor Positioning System (EDIPS), a WiFi-based system able to support the typical location requirements involved in loosely coupled mobile work. EDIPS is aimed for fast deployment and real-time operations rather than for location accuracy. The system was preliminary evaluated as a support for locating medical interns’ in a simulated hospital. The results obtained indicate the solution is able to locate nomadic workers in an indoor scenario, with enough accuracy to support loosely coupled mobile work, while requiring minimal setup effort.     

Emergency department patient-tracking system evaluation

Information technology is rapidly being developed and implemented for health care environments, often as a replacement for paper based or other manual tools. One example of this transition is the replacement of large dry-erase boards, used in emergency departments (ED) for tracking patient locations and clinical care, with computerized patient-tracking systems. The design of such systems has important implications for aspects of ED work, including changes to workload and situation awareness of ED staff. In this study, we used a newly developed electronic patient-tracking system simulator which combined a realistic model of ED and patient events with a configurable patient-tracking system display. Situation awareness regarding patient data, workload, responses to system failures, and performance on secondary tasks was measured for two groups of experienced ED staff (nurses, and clerks) across two display conditions and two patient volume conditions. We found that nurses had higher situation awareness than clerks, and that increased patient volume increased some aspects of workload. Additionally there were some indications that color coding information made it easier for participants to remember information in the event of system failures and that the choice of display size may depend on users’ primary tasks. As demonstrated by these important findings, the simulator was considered to be viable in adequately representing emergency department processes in a controlled lab setting for helping assess situation awareness and workload.

Relevance to industry

Healthcare technology design industry and healthcare systems planning to implement new information technologies would significantly benefit from the methodology and findings.     

Extracting trust information from security system of a service

The issue of trust is a research problem in emerging open environments, such as ubiquitous networks. Such environments are highly dynamic and they contain diverse number of services and autonomous entities. Entities in open environments have different security needs from services. Trust computations related to the security systems of services necessitate information that meets needs of each entity. Obtaining such information is a challenging issue for entities. In this paper, we propose a model for extracting trust information from the security system of a service based on the needs of an entity. We formally represent security policies and security systems to extract trust information according to needs of an entity. The formal representation ensures an entity to extract trust information about a security property of a service and trust information about whole security system of the service. The proposed model is applied to Dental Clinic Patient Service as a case study with two scenarios. The scenarios are analyzed experimentally with simulations. The experimental evaluation shows that the proposed model provides trust information related to the security system of a service based on the needs of an entity and it is applicable in emerging open environments.     

Internet-based mobile ad hoc networking

Internet-based mobile ad hoc networking is an emerging technology that supports self-organizing, mobile networking infrastructures. The technology enables an autonomous system of mobile nodes, which can operate in isolation or be connected to the greater Internet. Mobile ad hoc networks (Manets) are designed to operate in widely varying environments, from forward-deployed military Manets with hundreds of nodes per mobile domain to applications of low-power sensor networks and other embedded systems. Before Manet technology can be easily deployed, however, improvements must be made in such areas as high-capacity wireless technologies, address and location management, interoperability and security. The authors give an overview of Manet technology and current IETF efforts toward producing routing and interface definition standards that support it within the IP suite     

一种新的用于网络病毒监测定位的域名系统

针对网络环境下对被病毒感染网络节点准确定位的需要,构造了用于网络病毒监测定位的域名系统。病毒侵害主要影响文件系统,病毒驻存的主要载体为本地硬盘,因而将硬盘作为病毒监测网络的识别节点,并以主机的硬盘序列号作为网络终端节点的标识,应用DNS服务器的成熟技术和分布结构,实现节点硬盘序列号与IP地址的双向映射,并进行动态数据维护,达到了对网络节点的准确辨识和定位。为网络上病毒感染节点的定位和查找,以及对病毒散布源头的追寻创造了条件。     

A general framework for analyzing techno-behavioural dynamics on networks

A general framework for assessing future impacts of technology on society and environment is presented. The dynamics between human activity and technological systems impact upon many processes in society and nature. This involves non-linear dynamics requiring an understanding of how technology and human behaviour influence each other and co-evolve. Conventionally, technological and behavioural systems are analyzed as separate entities. We develop an integrated theoretical and methodological approach termed techno-behavioural dynamics focussing on networked interactions between technology and behaviour across multiple system states. We find that positive feedback between technology learning, evolving preferences and network effects can lead to tipping points in complex sociotechnical systems. We also demonstrate how mean-field and agent-based models are complimentary for capturing a hierarchy of analytical resolutions in a common problem domain. Assessing and predicting co-evolutionary dynamics between technology and human behaviour can help avoid systems lock-in and inform a range of adaptive responses to environmental and societal risk.     

Optimal capacity management and planning in services delivery centers

This paper considers human server systems of queues that arise within the information technology services industry. We develop a two-phase stochastic optimization solution approach to effectively and efficiently address the capacity management and planning processes of information technology services delivery centers. A large collection of numerical experiments of real-world human server system environments investigates various issues of both theoretical and practical interest, quantifying the significant benefits of our approach as well as evaluating the financial-performance trade-offs often encountered in practice.     

A TRAINING SIMULATION SYSTEM WITH REALISTIC AUTONOMOUS SHIP CONTROL

In this article we present a computational approach to developing effective training systems for virtual simulation environments. In particular, we focus on a Naval simulation system, used for training of conning officers. The currently existing training solutions require multiple expert personnel to control each vessel in a training scenario, or are cumbersome to use by a single instructor. The inability of current technology to provide an automated mechanism for competitive realistic boat behaviors thus compromises the goal of flexible, anytime, anywhere training. In this article we propose an approach that reduces the time and effort required for training of conning officers, by integrating novel approaches to autonomous control within a simulation environment. Our solution is to develop intelligent, autonomous controllers that drive the behavior of each boat. To increase the system's efficiency we provide a mechanism for creating such controllers, from the demonstration of a navigation expert, using a simple programming interface. In addition, our approach deals with two significant and related challenges: the realism of behavior exhibited by the automated boats and their real-time response to changes in the environment. In this article, we describe the control architecture we developed that enables the real-time response of boats and the repertoire of realistic behaviors we designed for this application. We also present our approach for facilitating the automatic authoring of training scenarios and we demonstrate the capabilities of our system with experimental results.     

无线局域网中基于信号强度的快速定位算法研究

无线局域网的定位技术是跟踪无线终端的重要方法,通过无线定位可以了解无线终端的行为意图,因此无线局域网定位技术越来越受到人们的关注。在无线局域网的室内定位中,由于室内距离近、结构相对复杂,障碍物的影响难以忽略,各种噪声的干扰是室内定位的困难之一。本文是为了确定用户的位置信息,提出了快速无线局域网定位方法。通过实验证明,该方法是一种高效可行的定位技术。     

采用EKF与PF的室内融合定位技术

在室内定位的复杂环境中,WiFi指纹法的定位性能易受信号波动的影响,行人航位推算方法(Pedestrian Dead Reckoning,PDR)的定位误差会随时间逐渐累积,为了解决这两个方面的问题,提出了一种采用扩展卡尔曼滤波(Extended Kalman Filter,EKF)与粒子滤波(Particle Filter,PF)的融合定位技术,该技术通过融合WiFi指纹法和优化后的行人航位推算方法来提高定位精度。在WiFi指纹法模块,该技术采用传统的加权k近邻法进行定位。在行人航位推算模块,该技术融合多种传感器进行航向估计,改进传统的非线性模型进行步长估计,使优化后的行人航位推算方法更适用于复杂环境中的实际应用。最后,结合粒子滤波和室内地图信息,该技术能够校正估计位置并进一步提高定位精度。通过实验表明,本文提出的融合校正方法能够有效提高定位精度。