A Review of Device-Free Indoor Positioning for Home-Based Care of the Aged:Techniques and Technologies

With the development of urbanization,the problem of neurological diseases brought about by population aging has gradually become a social problem of worldwide concern.Aging leads to gradual degeneration of the central nervous system,shrinkage of brain tissue,and decline in physical function in many elderlies,making them susceptible to neurological diseases such as Alzheimer’s disease(AD),stroke,Parkinson’s and major depressive disorder(MDD).Due to the influence of these neurological diseases,the elderly have troubles such as memory loss,inability to move,falling,and getting lost,which seriously affect their quality of life.Tracking and positioning of elderly with neurological diseases and keeping track of their location in real-time are necessary and crucial in order to detect and treat dangerous and unexpected situations in time.Considering that the elderly with neurological diseases forget to wear a positioning device or have mobility problems due to carrying a positioning device,device-free positioning as a passive positioning technology that detects device-free individuals is more suitable than traditional active positioning for the home-based care of the elderly with neurological diseases.This paper provides an extensive and in-depth survey of device-free indoor positioning technology for home-based care and an in-depth analysis of the main features of current positioning systems,as well as the techniques,technologies andmethods they employ,fromthe perspective of the needs of the elderly with neurological conditions.Moreover,evaluation criteria and possible solutions of positioning techniques for the home-based care of the elderly with neurological conditions are proposed.Finally,the opportunities and challenges for the development of indoor positioning technology in 6G mobile networks for home-based care of the elderly with neurological diseases are discussed.This review has provided comprehensive and effective tracking and positioning techniques,technologies and methods for the elderly,by which we can obtain the location information of the elderly in real-time and make home-based care more comfortable and safer for the elderly with neurological diseases.

THE APPLICATION OF SATELLITE POSITIONING TECHNOLOGY AND ITS INDUSTRIALIZATION IN CHINA

Satellite positioning technology has been widely used in all kinds of military and civil land, marine, space and aeronautical target positioning tasks, naviga tion activities and accurate surveying measurements since 90 s in the last cen tury due to its advantage in providing all-weather, real-time, three dimensional and high precision positioning information, as well as speed and accurate timing information. By now, it has already formed a new hi-tech industry basically.This paper briefly reviews the development of the global satellite positioning and navigation technologies including the basic information of China's "Plough navigation system", introduces the history of satellite positioning technology and its major application fields as well as the status quo of this being industri alized trade in China, gives an account of the writers' vision for the application and prospect of the satellite positioning technologies in China, and approaches the tactics and stresses of the satellite positioning technology's application and its industrialization future in China.

Application of the Spectrum Peak Positioning Technology Based on BP Neural Network in Demodulation of Cavity Length of EFPI Fiber Optical Sensor

An Extrinsic Fabry-Perot Interferometric (EFPI) fiber optical sensor system is an online testing system for the gas density. The system achieves the measurement of gas density information mainly by demodulating the cavity length of EF- PI fiber optical sensor. There are many ways to achieve the demodulation of the cavity length. For shortcomings of the big intensity demodulation error and complex structure of phase demodulation, this paper proposes that BP neural net-work is used to locate the special peak points in normalized interference spectrum and combining the advantages of the unimodal and bimodal measurement achieves the demodulation of the cavity length. Through online simulation and actual measurement, the results show that the peak positioning technology based on BP neural network can not only achieve high-precision demodulation of the cavity length, but also achieve an absolute measurement of cavity length in large dynamic range.

The Design and Implementation of High-rise Building Construction Based on GPS Positioning Technology

Baseline observation as well as height measurement is the important content of the quality control of high-rise building construction.In order to strengthen the quality of construction projects,meet the requirement of completion time,improve the accuracy and efficiency of locating observation and explore a scientific way of observation suitable for high-rise building construction,this paper studies the design and implementation of high-rise building construction based on GPS positioning technology.

Performance Evaluation of Three-Dimensional UWB Real-Time Locating Auto-Positioning System for Fire Rescue

Fire rescue challenges and solutions have evolved from straightfor-ward plane rescue to encompass 3D space due to the rise of high-rise city buildings.Hence,this study facilitates a system with quick and simplified on-site launching and generates real-time location data,enabling fire rescuers to arrive at the intended spot faster and correctly for effective and precise rescue.Auto-positioning with step-by-step instructions is proposed when launching the locating system,while no extra measuring instrument like Total Station(TS)is needed.Real-time location tracking is provided via a 3D space real-time locating system(RTLS)constructed using Ultra-wide Bandwidth technology(UWB),which requires electromagnetic waves to pass through concrete walls.A hybrid weighted least squares with a time difference of arrival(WLS/TDOA)positioning method is proposed to address real path-tracking issues in 3D space and to meet RTLS requirements for quick computing in real-world applications.The 3D WLS/TDOA algorithm is theoretically constructed with the Cramer-Rao lower bound(CRLB).The computing complexity is reduced to the lower bound for embedded hardware to directly compute the time differential of the arriving signals using the time-to-digital converter(TDC).The results of the experiments show that the errors are controlled when the positioning algorithm is applied in various complicated situations to fulfill the requirements of engineering applications.The statistical analysis of the data reveals that the proposed UWB RTLS auto-positioning system can track target tags with an accuracy of 0.20 m.

The Positive Influence of Buddhism Upon the Development of Science and Technology in Ancient China

It is important and worthwhile to discuss what kind of influence Buddhism cast on the development of science and technology in ancient China. The author does not agree with Joseph Needham’s view:“There can be little doubt that on the whole its action was powerfully inhibitory”, and the author thinks Buddhism took a positive promotion and influence on the development of science and technology in ancient China as a whole. There were four main ways of Chinese Buddhism influence on ancient science and technology:(1) The Buddhist scriptures actually contain a wealth of knowledge of science and technology;the eminent Buddhist monks introduced them into China through translation, therefore enriched contents of science and technology in ancient China.(2) Some knowledge of science and technology in ancient Indian and other districts got into China along with the spread of Buddhism.(3) Ancient Chinese Buddhists took part in science and technology practice actively at that time, and they had got a series of achievements in science and technology.(4) Being inspired and affected by Buddhist scientific knowledge, those non-Buddhist scientists had engaged in many created work in a further step, and made much contributions to development of science and technology. The doctrine of Buddhism was not a complete hindrance to the development of science and technology, and the result turned out contrary in many respects that it had promoted development of science and technology. In fact, Chinese Buddhism had made many important contributions in the fields of astronomy, mathematics, medicine, and so on.

The Positive Influence of Confucianism Upon the Development of Science and Technology—A Comment on Joseph Needham’s Prejudice

Has Confucianism exerted a positive influence or a passive one on the development of ancient science and technology?This is a question that has been debated repeatedly in the field of scientific history and philosophy and has not been settled up to now.A large number of scientific historians hold the opinion that the influence that Confucianism exerted on the development of science and technology is basically passive and negative.One of the most prominent representatives of this view is the famous historian on Chinese science and technology history—British Dr.Joseph Needham.Dr.Joseph Needham declared in the second volume of Science and Civilization in China,namely History of Scientific Thought:“They(Confucians)were thus,throughout Chinese history,in opposition to those elements which groped for a scientific approach to Nature,and for a Scientific interpretation and extension of technology”(Needham,1956,p.9),“their contribution to science was almost wholly negative”(p.1).As Confucianism has been playing an important role in ancient Chinese society for a long time,it is necessary for us to discuss this issue in detail.

Wireless Positioning Technologies in CDMA System

Location services not only provide address information, but also locate, monitor and track terminals on a real-time basis. To deliver fast and accurate location services, it is necessary to select an appropriate positioning method. Currently, 3 methods are available for CDMA wireless positioning: network based, Mobile Station (MS) based, and GpsOne positioning.As these methods are different in location time, accuracy, availability, privacy, and operation cost, they shall be selected according to the actual network conditions. Network structure, information bearer protocols, and transport mode make the basis of a wireless positioning system. They can be implemented in different ways, and some details shall be specified by the operators.

Chaotic pulse position modulation ultra-wideband system based on particle filtering

Traditional chaotic pulse position modulation(CPPM)system has many drawbacks.It introduces delay into the feedback loop,which will lead to divergence of chaotic map easily.The wrong decision of data will cause error propagation.Mismatch of parameters and synchronization error between the receiver and transmitter will arouse high bit error rate.To solve these problems,a demodulation algorithm of CPPM based on particle filtering is proposed.According to the mathematical model of the system,it tracks the real signal by online separation in demodulation.Simulation results show that the proposed method can track the true signal better than the traditional CPPM scheme.What's more,it has good synchronization robustness,reduced error propagation by wrong decision and low bit error rate.

Ultra-Wideband RoF System and Its Key Technologies

The microwave photonic technology-based Ultra-Wideband (UWB) Radio over Fiber (RoF) system is an important solution to the future low-cost and high-performance ultra-wideband wireless access network.Much research work has been done in this field with abundant results.This article introduces the RoF system that is based on the all-optical vector modulation technology to further enhance signal’s spectrum efficiency;the full-duplex RoF system that is based on the millimeter wave Phase-Shift Keying (PSK) modulation to greatly simplify base station structure and fiber layout;and the RoF system that is based on multi-service mixed transmission to carry the service with both wired signal and several wireless signals.The article also presents an RoF-based high-definition video transmission platform.

Vehicle Positioning Method Based on RFID in Vehicular Ad-Hoc Networks

With the rapid development of vehicular ad hoc network( VANET) technology,VANET applications such as safe driving and emergency rescue demand high position accuracy,but traditional GPS is difficult to meet new accuracy requirements. To overcome this limitation,a new vehicle positioning method based on radio frequency identification( RFID) is proposed. First RFID base stations are divided into three categories using fuzzy technology,and then Chan algorithm is used to calculate three vehicles' positions,which are weighed to acquire vehicles' accurate position. This method can effectively overcome the problem that vehicle positioning accuracy is not high resulting from the factors such as ambient noise and base distribution when Chan algorithm is used. Experimental results show that the performance of the proposed method is superior to Chan algorithm and 2-step algorithm based on averaging method,which can satisfy the requirements of vehicle positioning in VANETs.

Offline handover location positioning for map matching of mobile probes

Handover location technology was employed for collecting road traffic information in a number of field projects, and the project results demonstrate that it is a supplementary and promising means of road traffic information collection for further traffic supervision and maintenance. Because handover location technology is one kind of pattern matching based location technologies, offiine handovex location positioning is an essential problem to be studied for successfully matching mobile probes on GIS map. Offline handover location positioning method involves two stages, handover location positioning respectively via two weighted models and an optimized model based on the intermediate results obtained in the first stage. A preliminary field test is conducted on a stretch of freeway in the inner suburban region in Beijing, and performance evaluation results show that the proposed method is superior to standard least square model in location accuracy and location precision, which is an effective method of offline handover location positioning.

Research on key control technologies of all-position automatic welding machine

The pipeline all-position automatic welding machine system is a special welding system for automatically welding circumferential joint of pipeline on site, which has been widely used to the long-distance pipeline construction projects due to the advantages of automatic control for welding parameters at all-position, moving speed of bugs and operating. In this paper, the key control technologies of PAWM all-position automatic welding machine （ developed by Pipeline Research Institute of CNPC） such us the automatic control system, control software, personal digital assistant （PDA） software and complex programmable logic device （ CPLD ） program as well us the control method of welding parameter have been described detailedly. With the higher welding quality, higher welding effwiency and lower labor intensity, PA WM all-position automatic welding machine has been successfully applied in many famous pipeline construction projects.

Research on Library Management System based on RFID Technology

This paper analyses the demand of intelligent bookshelf system, designed the overall structure of intelligent Library shelves system based on RFID and create the system use case model. The analysis and design of the intelligent bookshelf system structure from two aspects of hardware and software, puts forward the three layer system structure model of intelligent bookshelf system based on RFID technology. The paper provide the analysis method and the design ideas of library intelligent bookshelf system, has the very high application value, contribute to the realization of library intelligent management and improve the level of library services, provide a useful reference to the development of current book positioning system and intelligent goods shelf system solution.

积极伦理观下算法歧视治理模式的革新

算法技术已借助大数据技术被广泛应用,成为影响人们日常生活的重要角色,其也因技术中立性不断遭受现实挑战而呈现出事实上的歧视性。重新审视算法歧视及其治理路径是发挥算法积极作用、避免算法消极影响的重要前提。传统伦理观念影响下的算法歧视治理模式存在价值观念偏航、治理结构失衡及技术治理落后的问题,影响算法歧视治理实效。社会发展促进了伦理观念的革新,积极伦理观的树立可以为算法技术向善的实现提供理论指引。算法治理结构的优化及反歧视技术水平的提高是纠正算法歧视的重要前提,理念、制度及技术三维措施的综合运用方可在算法领域实现科技向善的伦理目标。

技术与法学共视下人工智能体的角色定位

当前人工智能体的刑事责任问题研究整体上仍限于刑法学,应在技术和法学共视下展开一体化探讨。在技术原理上,人工智能体属于机器,不具有自我意识,因而不具有类人般的智能性;认可人工智能体具备刑事责任主体资格的刑法学观点,属假设性理论构想,当前缺乏技术原理上的现实基础。在技术视野下,人工智能体之“刑罚措施”等同机器处置,逻辑上不具有可行性,近乎幻想。人工智能体的刑法定位应归结为对人工智能体的开发者和使用者进行规制,从而保障人工智能在各种应用场景下的安全使用。

数字技术对制造业全球价值链分工地位升级影响研究

随着数字技术进步及其在经济各领域的快速应用,其对产业全球价值链(GVC)地位升级的推动作用日益显著。基于OECD-TiVA联合发布TiVA数据库2006—2018年的数据,以64个经济体为研究样本,实证检验数字技术对制造业GVC分工地位升级的影响。研究结果显示:数字技术显著促进制造业GVC分工地位的升级;提高劳动生产率、优化人力资本结构以及刺激消费需求,是数字技术促进制造业GVC分工地位升级的作用机制。异质性分析表明:数字技术对于低互联网发展水平以及中低收入经济体GVC分工地位升级的促进作用更为明显。据此提出,增强数字技术对我国制造业GVC分工地位升级的促进作用,应大幅提升我国数字技术创新和应用能力;增强贸易规则话语权,推动“数字贸易”发展;加快培养数字技术人才,加速推动消费结构升级。

强流脉冲束流位置探测器标定技术

电子直线感应加速器性能提升对束流探测器提出了高精度测量要求,由此不仅要求高精度的探测器设计装配技术,而且也要求探测器的准确标定。从强流脉冲束流位置探测器测量原理出发,从理论和实验两方面开展强流脉冲束流位置探测器标定技术研究。在理论上采用解析方法,分析了不同的计算处理方法和标定方法的标定效果,提出了特征平面标定,在建立的位置标定系统上,对用于多脉冲电子直线感应加速器的No.23电阻环进行了标定实验研究,实验结果验证了理论分析结果,根据理论和实验研究结果,确定了强流脉冲束流位置探测器标定方法。

基于改进LANDMARC定位算法的人员定位技术研究

在万物互联时代,通过定位系统完成人员定位监督成为了可能,同时该项技术也日益完善。当前,基于RFID无线视频技术的局域网人员定位被广泛应用于智慧园区员工管控、重点人员监管等方面。提出了一种基于RFID的局域网人员定位算法,通过优化LANDMARC算法,对采集到的信号分别引入高斯平滑滤波器和卡尔曼滤波器,去除影响信号强度的噪声,提升定位算法的稳定性;针对LANDMARC定位算法定位精度受K值影响较大的问题,引入Logistic回归模型,以提升算法定位的准确度,有效解决了RFID在有金属、水等障碍物情况下定位精度误差大的问题,降低了外界干扰,可为人员的精准定位提供技术手段。

数字孪生下的液压缸机械运行位置自动控制

液压缸机械系统非线性特征复杂,机械运行行为特征不明确,位置控制结果存在偏差,对此,该文提出数字孪生下的液压缸机械运行位置自动控制方法。连续检测液压缸机械系统运行状态,构建非线性状态方程,对比实际测量数据与输出数据的差异,选取RBF核函数与支持向量机,机械运行位置变化量,描述机械运行行为特征,建立位置控制目标函数,将最高适应度值对应的位置点自动更新为副本位置点,引入猫群算法求解目标函数,对位置控制目标函数的全局最优解展开更新,实现液压缸机械运行位置自动控制。实验结果表明,所提方法应用后,位移检测曲线与实际位移曲线之间的偏差较小,且在恒负载工况下和变负载工况下,位移稳态误差均较小,说明其机械运行位置自动控制结果精度高、控制效率高、控制精度高。