Navigation technology/eye-tracking in ophthalmology:principles,applications and benefits-a narrative review

Navigation technology in ophthalmology,colloquially called“eye-tracking”,has been applied to various areas of eye care.This approach encompasses motion-based navigation technology in both ophthalmic imaging and treatment.For instance,modern imaging instruments use a real-time eye-tracking system,which helps to reduce motion artefacts and increase signal-to-noise ratio in imaging acquisition such as optical coherence tomography(OCT),microperimetry,and fluorescence and color imaging.Navigation in ophthalmic surgery has been firstly applied in laser vision corrective surgery and spread to involve navigated retinal photocoagulation,and positioning guidance of intraocular lenses(IOL)during cataract surgery.It has emerged as one of the most reliable representatives of technology as it continues to transform surgical interventions into safer,more standardized,and more predictable procedures with better outcomes.Eye-tracking is essential in refractive surgery with excimer laser ablation.Using this technology for cataract surgery in patients with high preoperative astigmatism has produced better therapeutic outcomes.Navigated retinal laser has proven to be safer and more accurate compared to the use of conventional slit lamp lasers.Eye-tracking has also been used in imaging diagnostics,where it is essential for proper alignment of captured zones of interest and accurate follow-up imaging.This technology is not routinely discussed in the ophthalmic literature even though it has been truly impactful in our clinical practice and represents a small revolution in ophthalmology.

Speech Recognition Technology Applied to Intelligent Mobile Navigation System

The capability of human_computer interaction reflects the intelligent degree of mobile navigation system.The navigation data and functions of mobile navigation system are divided into system commands and non_system commands in this paper.And then a group of speech commands are abstracted.This paper applies speech recognition technology to intelligent mobile navigation system to process speech commands and does some deep research on the integration of speech recognition technology with mobile navigation system.The navigation operation can be performed by speech commands,which makes human_computer interaction easy during navigation.Speech command interface of navigation system is implemented by Dutty ++ Software,which is based on speech recognition system _Via Voice of IBM.Through navigation experiments,navigation can be done almost without keyboard,which proved that human_computer interaction is very convenient by speech commands and the reliability is also higher.

E-navigation发展与研究

阐述基于"大数据"理念、"互联网+"思维,及以"云技术"为支撑的由信息化技术、电子导航技术、E时代海事行业规范/标准、E-海事营运模式构架的新一代E-navigation技术及实现研究。

A tightly coupled rotational SINS/CNS integrated navigation method for aircraft

Strapdown inertial navigation system(SINS)/celestial navigation system(CNS)integrated navigation is widely used to achieve long-time and high-precision autonomous navigation for aircraft.In general,SINS/CNS integrated navigation can be divided into two integrated modes:loosely coupled integrated navigation and tightly coupled integrated navigation.Because the loosely coupled SINS/CNS integrated system is only available in the condition of at least three stars,the latter one is becoming a research hotspot.One major challenge of SINS/CNS integrated navigation is obtaining a high-precision horizon reference.To solve this problem,an innovative tightly coupled rotational SINS/CNS integrated navigation method is proposed.In this method,the rotational SINS error equation in the navigation frame is used as the state model,and the starlight vector and star altitude are used as measurements.Semi-physical simulations are conducted to test the performance of this integrated method.Results show that this tightly coupled rotational SINS/CNS method has the best navigation accuracy compared with SINS,rotational SINS,and traditional tightly coupled SINS/CNS integrated navigation method.

UPF based autonomous navigation scheme for deep space probe

The autonomous "celestial navigation scheme" for deep space probe departing from the earth and the autonomous "optical navigation scheme" for encountering object celestial body are presented. Then, aiming at the conditions that large initial estimation errors and non-Gaussian distribution of state or measurement errors may exist in orbit determination process of the two phases, UPF (unscented particle filter) is introduced into the navigation schemes. By tackling nonlinear and non-Gaussian problems, UPF overcomes the accuracy influence brought by the traditional EKF (extended Kalman filter), UKF (unscented Kalman filter), and PF (particle filter) schemes in approximate treatment to nonlinear and non-Gaussian state model and measurement model. The numerical simulations demonstrate the feasibility and higher accuracy of the UPF navigation scheme.

Cooperative Navigation for Autonomous Underwater Vehicles Based on Estimation of Motion Radius Vectors

A cooperative navigation algorithm for a group of autonomous underwater vehicles is proposed on the basis of motion radius vector estimation.Combined the dead reckoning data with the mutual range data through an acoustic communication network among the group members, the relative positioning problem can be solved. A novel approach for solving the relative positioning is presented by using a recursive trigonometry technique and extended Kalman filter(EKF). Simulation results verify the correctness and effectiveness of this navigation method.

Kalman filter applied in underwater integrated navigation system

For the underwater integrated navigation system, information fusion is an important technology. This paper introduces the Kalman filter as the most useful information fusion technology, and then gives a summary of the Kalman filter applied in underwater integrated navigation system at present, and points out the further research directions in this field.

Energetic electron detection packages on board Chinese navigation satellites in MEO

Energetic electron measurements and spacecraft charging are of great significance for theoretical research in space physics and space weather applications.In this paper,the energetic electron detection package(EEDP)deployed on three Chinese navigation satellites in medium Earth orbit(MEO)is reviewed.The instrument was developed by the space science payload team led by Peking University.The EEDP includes a pinhole medium-energy electron spectrometer(MES),a high-energy electron detector(HED)based onΔE-E telescope technology,and a deep dielectric charging monitor(DDCM).The MES measures the energy spectra of 50−600 keV electrons from nine directions with a 180°×30°field of view(FOV).The HED measures the energy spectrum of 0.5−3.0 MeV electrons from one direction with a 30°cone-angle FOV.The ground test and calibration results indicate that these three sensors exhibit excellent performance.Preliminary observations show that the electron spectra measured by the MES and HED are in good agreement with the results from the magnetic electron-ion spectrometer(MagEIS)of the Van Allen Probes spacecraft,with an average relative deviation of 27.3%for the energy spectra.The charging currents and voltages measured by the DDCM during storms are consistent with the highenergy electron observations of the HED,demonstrating the effectiveness of the DDCM.The observations of the EEDP on board the three MEO satellites can provide important support for theoretical research on the radiation belts and the applications related to space weather.

Location Based Services Acceptance and Adoption Evaluation: An Investigation on Mobile Phone Users’ Response to Awareness and Utilization of LBS Technology in Nairobi Kenya

Location Based Navigation System (LBNS) is a specific Location Based Service (LBS) purely for navigational purpose. These systems resolve position of a user by using GNSS/GPS positioning technologies, to which supplementary information on goods and services are tagged. The navigation services have become popular and can be installed on mobile phones to provide route information, location of points of interest and user’s current location. LBS has continued to face challenges which include “communication” process towards user reference. Location Based Service System conveys suitable information through a mobile device for effective decision making and reaction within a given time span. This research was geared at understanding the state of LBS technology acceptance and adoption by users in Nairobi Kenya. To do this a quantitative study was carried out through a questionnaire, to investigate mobile phone users’ response on awareness and use of LBS technology. Testing the growth of this technology in this region compared to predictions in previous studies using Technology Acceptance Model (TAM), it is evident that many users may be aware of GPS functionality in mobile phones but are certainly yet to fully embrace the technology as they rarely use it. This points to some underlying challenges towards this technology within this part of the World, thereby recommending for deliberate monitoring and evaluation of LBS technology for sustenance growth based on user satisfaction and acceptance for improved usability.

Navigation and Control of the PRISMA Formation： In-Orbit Experience

This paper presents flight results and lessons learned from the Spaceborne Autonomous Formation Flying Experiment （SAFE） conducted by the German Space Operations Center in the frame of the Swedish PRISMA technology demonstration mission. PR1SMA involves two fully autonomous formation-flying spacecraft which have been launched in June 2010 in a dawn/dusk orbit at an altitude of 750 km. SAFE represents one of the first demonstrations in low Earth orbit of an advanced guidance, navigation and control system for dual-spacecraft formations. Innovative techniques based on carrier-phase differential GPS （Global Positioning System）, relative eccentricity/inclination vectors and impulsive maneuvering are validated and tuned in orbit to achieve centimeter accurate real-time relative navigation, reliable formation keeping at the meter level and flexible formation reconfiguration capabilities. The technologies demonstrated within SAFE are considered as key precursors of future distributed satellite systems for unrivaled remote sensing and space exploration.

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.

Innovations in Retinal Laser Technology

Retinal laser photocoagulation is a proven, effective treatment for various retinal disorders, including diabetic retinopathy, retinal vein occlusions, and sickle cell retinopathy. To minimize iatrogenic retinal damage while maintaining therapeutic effects, retinal laser technology has evolved significantly since its introduction in ophthalmology more than half a century ago. These innovations have included both optimizations of laser parameters in addition to the development of novel laser delivery systems. This review summarizes recent innovations in retinal laser technology, including subthreshold micropulse laser, selective retinal therapy and nanosecond laser, innovative modes of laser delivery including pattern scanning laser, endpoint management, navigated laser, and newly described photo-mediated ultrasound therapy.

跨界颠覆性创新的早期识别方法及实证检验

[研究目的]数字经济时代,越来越多的企业利用互联网技术开展跨界颠覆性创新。探讨跨界颠覆性创新的早期判断和识别方法,对于打破国外核心技术封锁,抢占科技制高点具有重大意义。[研究方法]根据跨界颠覆性创新的演进特点,从技术和市场两个方面提出识别跨界颠覆性创新的理论框架:首先,基于专利文本,利用LDA主题模型提取跨界技术主题;其次,从成长性、融合性、影响力和引用行业外新知识等四个特征考察技术主题跨界颠覆的技术潜力;最后,基于专利、用户和专家评论数据,借助LDA主题模型与情感分析方法,从易扩散性、需求贴合度与市场吸引力趋势等特征考察技术主题跨界颠覆的市场潜力。[研究结论]以手机定位与导航技术为例,通过考察其跨界颠覆的技术潜力特征和市场潜力特征,验证了跨界颠覆性技术早期识别方法的可用性与有效性,为企业跨界颠覆性创新实践提供借鉴。

混合现实技术在口腔颌面部肿瘤诊疗中的应用

口腔颌面部肿瘤是口腔颌面外科的常见疾病,以虚拟手术设计、手术导航为代表的数字化外科技术目前已成为口腔颌面部肿瘤外科诊治的主要辅助手段。然而,现有的数字化技术在三维可视化成像、术中手眼配合等方面仍存在提升空间。目前,以混合现实技术为代表的三维可视化技术已经在医学领域迅速发展和应用,通过将三维虚拟图像叠加到真实的手术环境中,可辅助实现医学影像实时立体呈现,已逐步应用于口腔颌面部肿瘤的诊治中。术前可基于影像数据构建肿瘤及其周边重要结构三维模型,在混合现实环境中,进行个性化术前评估和手术方案设计;术中将混合现实技术与手术导航技术相结合,可以在术区真实环境中实时显示三维虚拟模型,克服单纯使用导航技术的手眼协调问题,进一步提高口腔颌面部肿瘤手术的精确性和安全性。混合现实技术与远程互联网医疗技术相结合,还可以提供高质量的教学平台,推动地区口腔颌面外科诊疗水平的发展。混合现实技术的局限性主要在于术区影像遮挡、单纯使用时精度不足、配准时间长等。笔者结合国内外文献报道以及本课题组的临床实践,对混合现实技术在口腔颌面部肿瘤诊疗中的应用进行归纳与总结。

基于5G电子通信的无人机导航网络信号抗干扰技术

为提升无人机在自主飞行过程中传输导航网络信号时的抗干扰能力,研究基于5G电子通信技术的无人机导航网络信号抗干扰技术。构建无人机通信结构,结合5G电子通信技术与电力线通信技术创建无人机导航网络信号模型;通过频谱感知方法中的能量检测算法建立无人机干扰信号检测模型,利用自适应滤波算法抑制干扰信号以及噪声干扰,实现无人机导航网络信号干扰抑制。实验结果表明,该方法具备不同干扰模式下的信号抗干扰能力。

面向智能航行避碰决策与规划的虚拟仿真测试技术研究

研究了面向智能航行避碰决策与规划的虚拟仿真测试技术。介绍了智能航行在货运船舶中的应用需求,分析了当下避碰决策策略、路径规划算法以及避碰决策与规划测试技术的研究现状。面向货运船舶智能航行避碰决策与规划能力,基于避碰规则中的会遇态势划分,结合四元船舶领域和贝塞尔曲线插值理论,提出了一种智能航行避碰决策与规划算法。构建了一种基于虚拟仿真环境的避碰决策与规划算法仿真测试方法,通过AIS(automatic identification system)模拟器模拟目标船的状态数据,结合船载综合导航系统(integrated navigation system,INS)实现了避碰决策与规划算法的测试。通过复杂水域仿真测试验证了所提算法的有效性和可行性,为货运船舶智能航行功能的开发与实践提供了参考。

新时代航海类专业课程思政建设路径与实践

在新时代背景下,航海类专业课程与思政教育融合的重要性日渐突出。从院校、教师、学生和社会四个层面,系统分析航海类专业课程思政建设面临的困境,提炼航海类专业课程思政的主要元素,提出系统谋划构建协同育人长效机制、多措并举完善专业协同育人课程体系、凝心聚力提升教师协同育人教学水平、价值引领促进学生内在动力的提升路径。

北斗全球卫星导航系统工程技术与管理创新

北斗全球卫星导航系统由中国自主建设运行,具备向全球用户提供全天时、全天候、高精度定位、导航和授时服务能力,具有报文通信、国际搜救等功能。北斗全球卫星导航系统坚持“自主、开放、兼容、渐进”的发展原则,发挥新型举国体制优势,全面突破核心关键技术,创新发展工程管理模式,实现了国际卫星导航领域和我国航天领域的多个首创,提前半年完成建设,走出了一条符合我国国情、独具特色的国家超级工程发展道路。本文围绕北斗全球卫星导航系统任务要求,全面阐述工程任务组成、任务进程和系统应用,从“混合星座、通信导航融合、星间链路、导航信号、快速组网、核心产品国产化”等方面梳理系统技术特点与创新,并总结了北斗工程建设过程中组织、技术、进度、质量和运行服务等管理体系的创新举措。

机器人导航技术在股骨颈骨折微创内固定治疗中的应用效果分析

目的 探究机器人导航技术在股骨颈骨折微创内固定治疗中的应用效果。方法 选取2020年4月—2023年4月保定市第一中心医院接收的102例股骨颈骨折患者为研究对象。采用随机数字表法分为徒手组(51例,采用传统徒手空心钉内固定)和机器组(51例,采取机器人辅助下空心钉内固定)。比较两组患者手术指标、影像学资料、髋关节功能、股骨颈短缩分级情况以及术后并发症发生率。结果 机器组患者手术时间短于徒手组,术中出血量低于徒手组,导针钻孔次数少于徒手组,住院时间、骨折愈合时间均短于徒手组(P <0.05);机器组患者前倾角、颈干角偏离度均低于徒手组(P <0.05);两组患者的髋关节退变情况构成比比较,差异无统计学意义(P>0.05);机器组患者Harris评分、髋伸屈活动度、髋内旋外旋活动度均高于徒手组(P <0.05),Fernandez-Esteve骨痂评分低于徒手组(P <0.05)。机器组患者的股骨颈短缩分级情况优于徒手组(P <0.05)。机器组的术后感染、退钉、神经损伤、骨折愈合不佳等并发症发生率低于徒手组(P <0.05)。结论 机器人导航技术在股骨颈骨折微创内固定治疗中能够提高手术精准度,缩短手术和恢复时间,改善术后股骨颈功能恢复,降低并发症风险,提高患者满意度,具有良好的应用前景。