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A Study of Zhang Peiji ' s English Version of The Sight of Father's Back
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作者 曾凡梅 《海外英语》 2018年第1期188-189,共2页
Mr.zhang peiji, a translator of The Sight of Father's Back, is a famous modern Chinese translation theorist and translator.He has made a great contribution to both translation theory and translation practice. His ... Mr.zhang peiji, a translator of The Sight of Father's Back, is a famous modern Chinese translation theorist and translator.He has made a great contribution to both translation theory and translation practice. His translation practice includes fictions, dramas, biography and essays. This paper is an attempt to make a study of Zhang Peiji's English version of The Sight of Father's Back. 展开更多
关键词 Zhang Peiji the sight of Father’s back TRANSLATION
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The Influences of the "Eight Sights" Culture on Modern Landscape Design 被引量:1
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作者 申月华 李硕 李品 《Journal of Landscape Research》 2009年第1期75-78,共4页
The cultural details and characteristics of 'Eight sights',which were existent but ignored,were found out through the introduction of the origin and the development of 'Eight sights'.The influences of ... The cultural details and characteristics of 'Eight sights',which were existent but ignored,were found out through the introduction of the origin and the development of 'Eight sights'.The influences of the 'Eight sights' on modern landscape design were summarized,reflecting the regional and cultural characteristics.The practical significance of re-examining the 'Eight sights' for the development of our garden landscape was pointed out. 展开更多
关键词 EIGHT sights CULTURE REGIONAL CHARACTERISTIC MODERN LANDSCAPE
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Analysis of the Development Countermeasure for Zhuhai Sight-seeing Agriculture 被引量:1
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作者 常诚 区晓琳 饶婷婷 《Journal of Landscape Research》 2009年第9期91-95,共5页
The advantages of the geographical conditions,natural,and cultural environment of Zhuhai agri-tourism are introduced,and the related development countermeasure is put forward.
关键词 sight-seeing AGRICULTURE Zhuhai DEVELOPMENT COUNTERMEASURE
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A new method to determine the gravity field of small bodies from line-of-sight acceleration data 被引量:1
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作者 Nian-Chuan Jian Jian-Guo Yan +2 位作者 Jin-Song Ping Jean-Pierre Barriot J.Alexis P.Rodriguez 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2019年第3期155-164,共10页
We present a new method to derive line-of-sight acceleration observables from spacecraft radio tracking data. The observables can be used to estimate the mass and gravity of a natural satellite as a spacecraft flyby. ... We present a new method to derive line-of-sight acceleration observables from spacecraft radio tracking data. The observables can be used to estimate the mass and gravity of a natural satellite as a spacecraft flyby. The corresponding observation model adapts to one-way and two/three-way tracking modes. As a test case for method validation and application, we estimated the mass and degree two gravity field for the Martian moon Phobos using simulated tracking data when the spacecraft Mars Express flew by Phobos on 2013 December 29. We have a few real tracking data during flyby and they will be used to confirm raw data simulation. The main purpose of this paper is to demonstrate the method of line-of-sight acceleration reduction from raw tracking data and the feasibility to estimate mass and gravity of a natural satellite using this type of observable. This novel method is potentially applicable to planet and asteroid gravity field studies combined with Doppler tracking data. 展开更多
关键词 line of sight acceleration-Doppler-celestial MECHANICS
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Comparison of visual effects of FS-LASIK for myopia centered on the coaxially sighted corneal light reflex or the line of sight 被引量:1
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作者 Jing Zhang Shi-Sheng Zhang +1 位作者 Qin Yu Jing-Cai Lian 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第4期624-631,共8页
AIM:To compare visual quality after femtosecond laser in situ keratomileusis(FS-LASIK),between the coaxially sighted corneal light reflex(CSCLR) group and conventional ablation line of sight(LOS) group.METHODS... AIM:To compare visual quality after femtosecond laser in situ keratomileusis(FS-LASIK),between the coaxially sighted corneal light reflex(CSCLR) group and conventional ablation line of sight(LOS) group.METHODS:In total,243 eyes(122 patients) were treated with centration on the CSCLR(visual axis) and 238 eyes(119 patients) treated with centration on the pupil center(LOS).Postoperative outcomes [uncorrected visual acuity(UCVA),best spectacle-corrected visual acuity(BSCVA)],safety index,efficacy index,refractive outcome,ablation center distance from the visual axis,corneal high-order aberrations,subjective discomfort glare and shadowing incidence rate,and contrast sensitivity at 1,3,and 6mo were measured and compared.RESULTS:The mean age was 27.77±7.1y in the CSCLR group and 26.03±7.70 y in the LOS group.Preoperatively,the manifest refraction spherical equivalent(MRSE) was-6.68±2.60 D in the CSCLR group and-6.65±2.68 D in the LOS group.The postoperative UCVA,BSCVA,MRSE(-0.03±0.263 D in the CSCLR group,-0.05±0.265 D in the LOS group),efficacy index(1.04,1.03),and safety index(1.09,1.08) were not significantly different between the groups(all P〉0.05).In total,3% lost one line and more of BSCVA in the CSCLR group,as 9% in the LOS group postoperatively(P〈0.05).The ablation center deviation was 0.20±0.15 mm from the visual axis(Pentacam system default setting;range,0-0.75 mm) in the CSCLR group,and 0.43±0.22 mm(range,0-1.32 mm) in the LOS group(P〈0.0001).Statistically significant greater augmentationof total corneal higher-order aberrations(0.15±0.10 μm and 0.20±0.12 μm respectively,P=0.03) and vertical and horizontal coma(P〈0.0001) were noted in the LOS group.Subjective discomfort glare and shadowing incidence rates were 8.59% and 17.5% in the CSCLR and LOS groups,respectively(P〈0.05).The 1-month postoperative contrast sensitivity visual acuity in the CSCLR group was significantly higher than that in the LOS group on contrast(100%,25%,10%) with a dark background,but there was no significant difference between the groups at 3 or 6m.CONCLUSION:Myopic LASIK centered on the CSCLR achieves significantly lower induction of loss of BSCVA,corneal high-order aberrations,and lower risk of subjective discomfort glare and shadowing,and lower decline in early contrast sensitivity by comparison with centration on the LOS,giving advantages in visual quality postoperatively. 展开更多
关键词 laser in situ keratomileusis ablation center line of sight coaxially sighted corneal light reflex
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Analytical Determination of Size and Location of Roadside Horizontal Sightline Offsets for Compound Curves
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作者 Timur Mauga 《Journal of Transportation Technologies》 2024年第1期119-135,共17页
AASHTO’s guideline for geometric design of highways and similar guidelines require that roadside areas on the inside of horizontal curves be cleared of high objects to provide stopping sight distance. The guidelines ... AASHTO’s guideline for geometric design of highways and similar guidelines require that roadside areas on the inside of horizontal curves be cleared of high objects to provide stopping sight distance. The guidelines have analytical models for determining the extent of clearance, known as the horizontal sightline offset or clearance offset, for simple curves. Researchers in the past have developed analytical models for clearance offsets for spiraled and reverse curves. Very few researchers developed analytical models for available sight distances for compound curves. Still missing are models for horizontal sightline offsets and locations of the offsets for compound curves. The objective of this paper is to present development of analytical models and charts for determining horizontal sightline offsets and their locations for compound curves. The paper considers curves whose component arcs are individually shorter than stopping sight distance. The resulting models and the charts have been verified with accurate values determined using graphical methods. The models and the charts will find application in geometric design of highway compound curves. 展开更多
关键词 sight Distance Roadside Clearance offsets Compound Curves
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Link Budget Design for RF Line-of-Sight via Theoretical Propagation Prediction 被引量:1
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作者 Anwar H. Ibrahim Mohammed F. Alsharekh +2 位作者 Mohammed S. Almanee Abdulrahman S. Al-Turki Muhammed Islam 《International Journal of Communications, Network and System Sciences》 2019年第1期11-17,共7页
Line-of-sight (LOS) link planning condition has been observed to have effects on the atmospheric factor which cause crucial signal loss. The main objective of the planning was to improve a set of a link using point to... Line-of-sight (LOS) link planning condition has been observed to have effects on the atmospheric factor which cause crucial signal loss. The main objective of the planning was to improve a set of a link using point to point condition to assist the performance in emerging its strategy for handling the fixed WLAN service. The purpose of this paper is to provide a quick description of various propagation loss mechanisms on Link Budget Tool (LBT). LBT is customized to create point to point link for local area network (LAN) through radio frequency range operating between 2.400 GHz and 5.800 GHz. This software is able to define the effect of signal loss and expected performances according to the distances between link propagation conditions based on a number of system parameters. 展开更多
关键词 Path Loss (PL) Line of sight (LOS) Microwave LINK BUDGET (MLB) LINK Planning (LP)
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Landscape Planning Based on Foreign Characteristic of Agricultural Sight-viewing Theme Park——A Case Study of Taiwan Peasants Innovation Park in Gucheng Town of Gaochun County in Nanjing City
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作者 刘玉石 杨婧 张纵 《Journal of Landscape Research》 2010年第9期33-36,共4页
Through the exploration of project planning mode of agricultural sight-viewing garden based on characteristics,the development object of Taiwan peasants innovation park in Gucheng Town of Gaochun County in Nanjing Cit... Through the exploration of project planning mode of agricultural sight-viewing garden based on characteristics,the development object of Taiwan peasants innovation park in Gucheng Town of Gaochun County in Nanjing City was analyzed and summarized. Feasibility study was conducted on the programs,relevant infrastructure and overall construction of landscape in the park,from which reasonable recognition and suggestion was put forward. It provided conceptual reference model which could be applied in construction of agricultural sight-viewing theme park and characteristic agricultural sight-seeing tourist destination in Nanjing Region. 展开更多
关键词 FOREIGN CHARACTERISTIC AGRICULTURAL sight-seeing theme PARK Landscape planning
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Suitability of the Euler’s Spiral for Roadside Clearance in Order to Provide Stopping Sight Distances
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作者 Timur Mauga 《Journal of Transportation Technologies》 2017年第3期221-239,共19页
The AASHTO’s guideline for geometric design, also known as the green book, requires that the inside of horizontal curves be cleared of obstructions to sight lines in order to provide sufficient sight distances. Recen... The AASHTO’s guideline for geometric design, also known as the green book, requires that the inside of horizontal curves be cleared of obstructions to sight lines in order to provide sufficient sight distances. Recently, innovative use of Euler’s spiral for determination of clearance offsets has been proposed. However, suitability of the offsets as minimum criteria has not been evaluated. This paper presents comparison between the proposed offsets and minimum offsets determined with the computational method suggested in the green book. Results of comparison show that offsets determined with innovative use of the Euler’s spiral are always longer than minimum values determined with the computational method. The differences in lengths of the two sets of offsets increase with decrease in curve radii. Therefore, on sites with large radii offsets determined through innovative use of the Euler’s spiral may be implemented in the field since the offsets are only slightly longer than minimum offsets. On sites with short radii some offsets on tangent sections are very long such that they result in extra cleared areas that will not accommodate sightlines. The areas that do not accommodate sightlines may result in unnecessary extra earthwork costs where highways are located in cut zones. Additionally, it has been suggested in this paper that designers also consider other curves, including elliptical arcs, for roadside clearance envelopes. One advantage of elliptical arcs is that they are flexible to align with boundaries of clear zones on tangent sections regardless of sizes of radii of horizontal curves. Besides, most offsets to elliptical arcs are comparable to those determined with the green book’s computation method. An example of design chart has been presented for practitioners to use. The chart is for minimum offsets needed to provide a given sight distance while gradually transitioning clearance from boundaries of clear zones on tangent sections. 展开更多
关键词 ROADSIDE CLEARANCE CLEARANCE ofFSETS sightline ofFSETS CLEARANCE Enve-lope sight Distance
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Review Paper on the Studies of Sight Translation and Sight Interpreting
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作者 陈淑娴 《海外英语》 2021年第8期84-85,共2页
Sight Translation is regarded as an indispensable skill prior to the study of Simultaneous Interpreting.And Sight Interpreting is employed in some settings like court interpreting and formal conferences.The importance... Sight Translation is regarded as an indispensable skill prior to the study of Simultaneous Interpreting.And Sight Interpreting is employed in some settings like court interpreting and formal conferences.The importance of studying Sight Translation and Sight Interpreting is apparent.This paper reviews the previous literatures on the studies of Sight Translation and Sight Interpreting in the West and in China over the past four decades for attaining a full picture on the studies in this field.This paper focuses on the function and significance of studying Sight Translation and Sight Interpreting from both home and abroad. 展开更多
关键词 sight Translation sight Interpreting Effort Models
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Application of the sun line-of-sight vector in the optimal attitude estimation of deep-space probe
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作者 常晓华 崔祜涛 邵巍 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2011年第2期96-100,共5页
This paper proposed an optimal algorithm using the sun line-of-sight vector to improve the probe attitude estimation accuracy in deep-space mission.Firstly,the elaborate analysis of the attitude estimation error from ... This paper proposed an optimal algorithm using the sun line-of-sight vector to improve the probe attitude estimation accuracy in deep-space mission.Firstly,the elaborate analysis of the attitude estimation error from vector observations was done to demonstrate that the geometric relation between the reference vectors is an important factor which influences the accuracy of attitude estimation.Then,with introduction of the sun line-of-sight vector,the attitude quaternion obtained from the star-sensor was converted into a pair of mutually perpendicular reference vectors perpendicular to the sun vector.The normalized weights were calculated according to the accuracy of the sensors.Furthermore,the optimal attitude estimation in the least squares sense was achieved with the quaternion estimation method.Finally,the results of simulation demonstrated the validity of the proposed optimal algorithm based on the practical data of the Deep Impact mission. 展开更多
关键词 sun line-of-sight vector attitude estimation deep-space probe
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Locating the position of objects in non-line-of-sight based on time delay estimation
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作者 王雪峰 王元庆 +1 位作者 苏金善 杨兴雨 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第8期163-169,共7页
Non-line-of-sight imaging detection is to detect hidden objects by indirect light and intermediary surface(diffuser).It has very important significance in indirect access to an object or dangerous object detection, ... Non-line-of-sight imaging detection is to detect hidden objects by indirect light and intermediary surface(diffuser).It has very important significance in indirect access to an object or dangerous object detection, such as medical treatment and rescue. An approach to locating the positions of hidden objects is proposed based on time delay estimation. The time delays between the received signals and the source signal can be obtained by correlation analysis, and then the positions of hidden objects will be located. Compared with earlier systems and methods, the proposed approach has some modifications and provides significant improvements, such as quick data acquisition, simple system structure and low cost, and can locate the positions of hidden objects as well: this technology lays a good foundation for developing a practical system that can be used in real applications. 展开更多
关键词 NON-LINE-of-sight time delay estimation CROSS-CORRELATION hidden object location
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INERTIAL INTEGRATED SYSTEM OF NORTH SEEKING/SIGHT STABILIZING ON VEHICLE 被引量:1
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作者 刘建业 徐珍 +1 位作者 杨莉 肖纪立 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2000年第2期157-162,共6页
A brand new method of automatic north seeking/sight stabilizing is introduced for usage in land fighting vehicles such as tank, etc. Some inertial devices are installed additionally on the platform along with relat... A brand new method of automatic north seeking/sight stabilizing is introduced for usage in land fighting vehicles such as tank, etc. Some inertial devices are installed additionally on the platform along with relative control circuits to make its function of North seeking possible. Double position calculation is adopted in this method, and by alignment at two sites the azimuth angle can be figured out. Also the orientation and the horizontal shifts of the gyro are simultaneously measured and compensated so as to improve the accuracy of north seeking. The system can automatically seek north when the vehicle is immobile. And the time consumption is no more than 5.5 min. Besides, the system can keep azimuth angle and provide tilt angle and pitch angle of the vehicle. 展开更多
关键词 north seeking sight stabilizing inertial platform shift measurement and compensation land fighting vehicle
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《The influence of institutional investors on myopic R&D investment behavior》述评
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作者 胡盛昌 干胜道 《内蒙古财经学院学报》 2012年第3期34-37,共4页
机构投资者作为证券市场中的重要力量,越来越受到理论界和实务界的关注。论文对宾夕法尼亚大学沃顿商学院会计学教授布赖恩-布希(Brian Bushee)的论文"The influence of institutional investors on myopic R&D investment beh... 机构投资者作为证券市场中的重要力量,越来越受到理论界和实务界的关注。论文对宾夕法尼亚大学沃顿商学院会计学教授布赖恩-布希(Brian Bushee)的论文"The influence of institutional investors on myopic R&D investment behavior"(机构投资者对企业短视研发投资行为的影响,以下简称Bushee(1998))进行评价并提出相关的建议和研究方向。 展开更多
关键词 机构投资者 盈余管理 短视 异质性
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A Deep Learning-Based Recognition Approach for the Conversion of Multilingual Braille Images 被引量:2
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作者 Abdulmalik AlSalman Abdu Gumaei +1 位作者 Amani AlSalman Suheer Al-Hadhrami 《Computers, Materials & Continua》 SCIE EI 2021年第6期3847-3864,共18页
Braille-assistive technologies have helped blind people to write,read,learn,and communicate with sighted individuals for many years.These technologies enable blind people to engage with society and help break down com... Braille-assistive technologies have helped blind people to write,read,learn,and communicate with sighted individuals for many years.These technologies enable blind people to engage with society and help break down communication barriers in their lives.The Optical Braille Recognition(OBR)system is one example of these technologies.It plays an important role in facilitating communication between sighted and blind people and assists sighted individuals in the reading and understanding of the documents of Braille cells.However,a clear gap exists in current OBR systems regarding asymmetric multilingual conversion of Braille documents.Few systems allow sighted people to read and understand Braille documents for self-learning applications.In this study,we propose a deep learning-based approach to convert Braille images into multilingual texts.This is achieved through a set of effective steps that start with image acquisition and preprocessing and end with a Braille multilingual mapping step.We develop a deep convolutional neural network(DCNN)model that takes its inputs from the second step of the approach for recognizing Braille cells.Several experiments are conducted on two datasets of Braille images to evaluate the performance of the DCNN model.The rst dataset contains 1,404 labeled images of 27 Braille symbols representing the alphabet characters.The second dataset consists of 5,420 labeled images of 37 Braille symbols that represent alphabet characters,numbers,and punctuation.The proposed model achieved a classication accuracy of 99.28%on the test set of the rst dataset and 98.99%on the test set of the second dataset.These results conrm the applicability of the DCNN model used in our proposed approach for multilingual Braille conversion in communicating with sighted people. 展开更多
关键词 Optical Braille recognition OBR Braille cells BLIND sighted deep learning deep convolutional neural network
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Minimum Clearance Offsets for Providing Desired Stopping Sight Distances at Simple Curves with Variable Operating Speeds 被引量:2
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作者 Timur Mauga 《Journal of Transportation Technologies》 2016年第3期107-117,共12页
Lateral clearance on the inside of horizontal curves is required by all geometric design guidelines in order to provide at least stopping sight distance. There already exist graphical models, analytical models, and de... Lateral clearance on the inside of horizontal curves is required by all geometric design guidelines in order to provide at least stopping sight distance. There already exist graphical models, analytical models, and design charts for determining minimum clearance offsets to meet the requirement. Some of these models determine the offsets based on constant design sight distance values on the assumption that drivers negotiate horizontal curves at constant speed. Therefore, those models are suitable for sites where there is no difference in speeds between tangent and curved sections. Past studies have reported that there are sites where drivers decelerate on entering horizontal curves and accelerate on departing from the curves. At those sites stopping sight distance for a given driver varies with driver location due to variable speed. This paper presents an analytical model and a chart for determining minimum offsets needed to provide desired sight distances at horizontal curves with variable operating speeds. At those sites the offsets yield roadside clearance boundaries that have transition arcs with performances that are similar to those of elliptical arcs. Therefore, practitioners may choose to use elliptical equations or equations and the chart developed herein. Results of this study will be of value to practitioners in the area of roadside design. 展开更多
关键词 sight Distance Roadside Clearance Clearance offsets sightline offsets Clearance Envelope
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Efficiency Effect of Obstacle Margin on Line-of-Sight in Wireless Networks 被引量:1
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作者 Murad A.A.Almekhlafi Taiseer Abdalla Elfadil Eisa +5 位作者 Fahd N.Al-Wesabi Abdelzahir Abdelmaboud Manar Ahmed Hamza Abdelwahed Motwakel Ishfaq Yaseen Mohammed Rizwanullah 《Computers, Materials & Continua》 SCIE EI 2022年第7期227-242,共16页
Line-of-sight clarity and assurance are essential because they are considered the golden rule in wireless network planning,allowing the direct propagation path to connect the transmitter and receiver and retain the st... Line-of-sight clarity and assurance are essential because they are considered the golden rule in wireless network planning,allowing the direct propagation path to connect the transmitter and receiver and retain the strength of the signal to be received.Despite the increasing literature on the line of sight with different scenarios,no comprehensive study focuses on the multiplicity of parameters and basic concepts that must be taken into account when studying such a topic as it affects the results and their accuracy.Therefore,this research aims to find limited values that ensure that the signal reaches the future efficiently and enhances the accuracy of these values’results.We have designed MATLAB simulation and programming programs by Visual Basic.NET for a semi-realistic communication system.It includes all the basic parameters of this system,taking into account the environment’s diversity and the characteristics of the obstacle between the transmitting station and the receiving station.Then we verified the correctness of the system’s work.Moreover,we begin by analyzing and studying multiple and branching cases to achieve the goal.We get several values from the results,which are finite values,which are a useful reference for engineers and designers of wireless networks. 展开更多
关键词 Line of sight obstacle margin wireless networks communication link radio wave propagation
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Calculation of Probability of Cloud-Free Lines-of-Sightat Given Heights in Foshan, China 被引量:1
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作者 李昀英 孙立潭 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1999年第2期297-303,共7页
Based on Lund and Shanklin’s work (1972), methods of calculating Probability of Cloud-Free Lines-of-Sight (PCFLOS), Persistence Probability of Cloud-Free Lines-of-Sight (PPCFLOS) and Recurrence Probability of Cloud-f... Based on Lund and Shanklin’s work (1972), methods of calculating Probability of Cloud-Free Lines-of-Sight (PCFLOS), Persistence Probability of Cloud-Free Lines-of-Sight (PPCFLOS) and Recurrence Probability of Cloud-free Lines-of-Sight (RPCFLOS) at given heights are presented. PCFLOS, PPCFLOS and RPCFLOS are calculated in Foshan, China by conventional observation data from 1961 to 1990. The conclusions are: (1) The higher the elevations, the smaller the PCFLOS and the larger the view angles, the larger the PCFLOS. (2) PPCFLOS and RPCFLOS decrease with the increase of elevation and the delay of time. (3) RPCFLOS is always equal to or larger than PPCFLOS at lag times. 展开更多
关键词 Probability of cloud-free lines-of-sight Persistence probability of cloud-free lines-of-sight Recurrence probability of cloud-free lines-of-sight Cloud climate
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Adaptive sliding-mode path following control system of the underactuated USV under the influence of ocean currents 被引量:10
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作者 CHEN Xiao LIU Zhong +2 位作者 ZHANG Jianqiang ZHOU Dechao DONG Jiao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第6期1271-1283,共13页
The path-following control of the asymmetry underactuated unmanned surface vehicle(USV) under external disturbances such as unknown constant and irrational ocean currents is discussed, and an adaptive sliding-mode pat... The path-following control of the asymmetry underactuated unmanned surface vehicle(USV) under external disturbances such as unknown constant and irrational ocean currents is discussed, and an adaptive sliding-mode path-following control system is proposed, which comprises a path-variable updated law,a modified integral line-of-sight(ILOS) guidance law based on a time-varying lookahead distance and adaptive feedback linearizing controllers combined with sliding-mode technique. A more accurate USV model without the assumption of having diagonal inertia and damping matrices is first presented, aiming at improving the performance of the path-following control. Next, the coordinate transformation is adopted to decouple the sway dynamic from the rudder angle, and the path-following errors dynamics without non-singular problem are presented in the moving Frenet-Serret frame. Then, based on the cascaded theorem and the adaptive sliding-mode method, the adaptive control law of position errors and course error are designed, among which the lookahead distance and integral gain are all computed as different functions of cross-track error to estimate and compensate the sideslip angle caused by external disturbances adaptively. Finally, according to the Lyapunov and cascaded theorem, the control system proposed is proved to be uniform globally asymptotic stability(UGAS) and uniform semiglobal exponential stability(USGES) when the control objectives are all achieved. Simulation results illustrate the precision and high-quality performance of this new controller. 展开更多
关键词 sliding-mode control unmanned surface vehicle(USV) integral line-of-sight(ILOS) path following proof of stability
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Demographic features and visual outcomes of patients presenting to diabetic photo-screening and treated for sight threatening retinopathy in Fiji
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作者 Riyaz Bhikoo Neil Murray +2 位作者 Biu Sikivou Stephanie Emma Charles McGhee 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第5期790-795,共6页
AIM:To describe the demographic features and visual outcomes of patients presenting to photo-screening services, and treated for sight threatening retinopathy(STR) in a low resource setting, Fiji.METHODS:A retrosp... AIM:To describe the demographic features and visual outcomes of patients presenting to photo-screening services, and treated for sight threatening retinopathy(STR) in a low resource setting, Fiji.METHODS:A retrospective review of all new patients who presented for diabetic photo-screening at the Diabetic Eye Clinic, Suva in 2010. Fundus images were graded using standardised guidelines. Patient demographics, retinopathy grading and visual acuity data were extracted from the database and analyzed. Patients that received laser therapy and still attending follow up in 2012 were examined for disease progressionRESULTS:Totally 2236 patients were photo-screened, 87%(3870/4472) of images were gradable. STR was observed in 26%(988/3870) with advanced STR(proliferative retinopathy/severe maculopathy) in 10%(385/3870). Of those with STR, 59% had BCVA ≥6/18, 31% with advanced STR were 〈6/60. Male gender [odds ratio(OR) 1.59; 1.20-2.12], history of hypertension(OR 1.36; 1.03-1.80) and peripheral neuropathy(OR 1.41; 1.01-1.95) were predictive of advanced STR. In 2012, 32%(315/988) attended follow up with 69% exhibiting advanced STR compared with 53% of the same cohort in 2010. Laser photocoagulation was administered to 212 eyes(212/3870, 5%) with retinopathy and maculopathy progression observed in 52% and 33% respectively. BCVA ≥6/18 was noted in 67%(143/212) of treated eyes. Improved glycaemic control(OR 46.52; 1.50-1441.90) amongst those with advanced STR was predictive of eyes that maintained good vision.CONCLUSION:In Fiji, a quarter of new patients presenting to photo-screening have STR with a third of those with advanced STR having already loss vision. Improved glycaemic control and timely treatment of patients with sight threatening complications is important in halting disease progression. 展开更多
关键词 diabetic retinopathy sight threatening PHOTOCOAGULATION pacific islands developing countries
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