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Research of Future Directions and Considerations for Implementation of the Forest City Strategy
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作者 Renrui Wang 《Journal of Geoscience and Environment Protection》 2024年第5期1-16,共16页
A “Forest City” (FC) is an urban area that has a significant amount of forest cover. It is now a green urban development strategy that is supported by numerous nations. This essay compares the many FC implementation... A “Forest City” (FC) is an urban area that has a significant amount of forest cover. It is now a green urban development strategy that is supported by numerous nations. This essay compares the many FC implementation strategies used in developed and developing countries and explores potential future paths for this tactic. The variations between FC in terms of measurement targets, air purification, street trees, and forestry development are thoroughly compared in this research. This essay goes on to explore FC’s potential in the future regarding policy changes and the environment based on this comparison. Therefore, this essay focuses on the necessity of considering industrial innovation, encouraging biodiversity, lowering greenhouse gas emissions, paying attention to forest restructuring, and being more responsive to the issues provided by urbanization in the future global implementation of FC. 展开更多
关键词 Forest City Policy Adjustment Ecological Environment measurement Objectives
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Measurement of a discontinuous object based on a dual-frequency grating
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作者 乔闹生 蔡新华 姚春梅 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第11期4881-4886,共6页
The dual-frequency grating measurement theory is proposed in order to carry out the measurement of a discontinuous object. Firstly, the reason why frequency spectra are produced by low frequency gratings and high freq... The dual-frequency grating measurement theory is proposed in order to carry out the measurement of a discontinuous object. Firstly, the reason why frequency spectra are produced by low frequency gratings and high frequency gratings in the field of frequency is analysed, and the relationship between the wrapped-phase and the unwrapping-phase is discussed. Secondly, a method to combine the advantages of the two kinds of gratings is proposed: one stripe is produced in the mutation part of the object measured by a suitable low frequency grating designed by MATLAB, then the phase produced by the low frequency grating need not be unfolded. The integer series of stripes is produced by a high frequency grating designed by MATLAB based on the frequency ratio of the two kinds of gratings and the high frequency wrapped-phase, and the high frequency unwrapping-phase is then obtained. In order to verify the correctness of the theoretical analysis, a steep discontinuous object of 600×600 pixels and 10.00 mm in height is simulated and a discontinuous object of ladder shape which is 32.00 mm in height is used in experiment. Both the simulation and the experiment can restore the discontinuous object height accurately by using the dual-frequency grating measurement theory. 展开更多
关键词 dual-frequency grating Fourier transform profilometry measurement of discontinuous object phase unwrapping
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3D Depth Measurement for Holoscopic 3D Imaging System
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作者 Eman Alazawi Mohammad Rafiq Swash Maysam Abbod 《Journal of Computer and Communications》 2016年第6期49-67,共19页
Holoscopic 3D imaging is a true 3D imaging system mimics fly’s eye technique to acquire a true 3D optical model of a real scene. To reconstruct the 3D image computationally, an efficient implementation of an Auto-Fea... Holoscopic 3D imaging is a true 3D imaging system mimics fly’s eye technique to acquire a true 3D optical model of a real scene. To reconstruct the 3D image computationally, an efficient implementation of an Auto-Feature-Edge (AFE) descriptor algorithm is required that provides an individual feature detector for integration of 3D information to locate objects in the scene. The AFE descriptor plays a key role in simplifying the detection of both edge-based and region-based objects. The detector is based on a Multi-Quantize Adaptive Local Histogram Analysis (MQALHA) algorithm. This is distinctive for each Feature-Edge (FE) block i.e. the large contrast changes (gradients) in FE are easier to localise. The novelty of this work lies in generating a free-noise 3D-Map (3DM) according to a correlation analysis of region contours. This automatically combines the exploitation of the available depth estimation technique with edge-based feature shape recognition technique. The application area consists of two varied domains, which prove the efficiency and robustness of the approach: a) extracting a set of setting feature-edges, for both tracking and mapping process for 3D depthmap estimation, and b) separation and recognition of focus objects in the scene. Experimental results show that the proposed 3DM technique is performed efficiently compared to the state-of-the-art algorithms. 展开更多
关键词 Holoscopic 3D Image Edge Detection Auto-Thresholding Depthmap Integral Image Local Histogram Analysis Object Recognition and Depth measurement
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Objective and subjective measures for sleep disorders 被引量:2
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作者 张琳 赵忠新 《Neuroscience Bulletin》 SCIE CAS CSCD 2007年第4期236-240,共5页
Subjective and objective measures of sleep structure or quality could help to characterize the chronic sleep disturbances, with relation to patients' risk factor profiles and co-morbidities. Studies have shown that d... Subjective and objective measures of sleep structure or quality could help to characterize the chronic sleep disturbances, with relation to patients' risk factor profiles and co-morbidities. Studies have shown that discrepancies can occur between subjective data regarding sleep disturbances and the impact of insomnia and objective assays, and surrogate markers of sleep and sleep disturbances. Both objective and subjective measures should be incorporated into clinic studies. It seems likely that sleep quality is represented by a combination of more than one subjective sleep parameter. Objective and subjective assessments of sleep quality may relate to different parameters. Future studies incorporated both subjective and objective measures could help to address the sleep disorders. 展开更多
关键词 objective measures subjective measures sleep disorders
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Wearable monitors criterion validity for energy expenditure in sedentary and light activities
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作者 Florez-Pregonero Alberto Meckes Nathanael +1 位作者 Buman Mathew Barbara E.Ainsworth 《Journal of Sport and Health Science》 SCIE 2017年第1期103-110,共8页
Background: Wearable monitors(WMs) are used to estimate the time spent in sedentary behaviors(SBs) and light-intensity physical activities(LPAs) and their associated energy cost; however, the accuracy of WMs in measur... Background: Wearable monitors(WMs) are used to estimate the time spent in sedentary behaviors(SBs) and light-intensity physical activities(LPAs) and their associated energy cost; however, the accuracy of WMs in measuring behaviors on the lower end of the intensity spectrum is unclear. The aim of this study was to assess the validity of 3 WMs(Acti Graph GT3X+; activ PAL, and Sense Wear 2) in estimating the intensity of SB and LPA in adults as compared with the criterion measure of oxygen uptake(VO_2) measured by indirect calorimetry.Methods: Sixteen participants(age: 25.38 ± 8.58 years) wore the ActiG raph GT3X+, activP AL, and SenseW ear 2 devices during 7 sedentary-to-light activities. VO_2(mL/kg/min) was estimated by means of a portable gas analyzer, Oxycon Mobile(Carefusion, Yorba Linda, CA, USA). All data were transformed into metabolic equivalents and analyzed using mean percentage error, equivalence plots, Bland-Altman plots, kappa statistics, and sensitivity/specificity.Results: Mean percentage error was lowest for the activ PAL for SB(14.9%) and LPA(9.3%) compared with other WMs, which were >21.2%.None of the WMs fell within the equivalency range of ±10% of the criterion mean value. Bland-Altman plots revealed narrower levels of agreement with all WMs for SB than for LPA. Kappa statistics were low for all WMs, and sensitivity and specificity varied by WM type.Conclusion: None of the WMs tested in this study were equivalent with the criterion measure(VO_2) in estimating sedentary-to-light activities;however, the activ PAL had greater overall accuracy in measuring SB and LPA than did the Acti Graph and Sense Wear 2 monitors. 展开更多
关键词 Accelerometers ACCURACY Low intensity Metabolic estimations Objective measurement Sedentary behaviors
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An Objective Measure to Evaluate Actual Body Shape among Children and Adolescents in China
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作者 FU Lian Guo WANG Hai Jun +5 位作者 LI Xiao Hui WANG Zhi Qiang Patrick WC Lau YANG Yi De MENG Xiang Kun MA Jun 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2014年第8期582-593,共12页
Objective The purpose of this study was to explore an objective measure to assess actual body shape of children and adolescents in China. Methods Based on the Chinese National Survey on Student's Constitution and He... Objective The purpose of this study was to explore an objective measure to assess actual body shape of children and adolescents in China. Methods Based on the Chinese National Survey on Student's Constitution and Health (CNSSCH) in 2005, 210 927 children and adolescents' (7-18 years) body height, body weight, chest circumference, sitting height, chest circumference-height ratio, chest circumference-sitting height ratio, chest circumference-low limb ratio, and sitting height-low limb ratio measurements were used to develop an objective measure by using transformation variables and explored factor analysis (EFA). Discrimination power of the objective measure was evaluated based on BMI reference and Receiver Operating Characteristic curves (ROC). Results The objective measure included four dimensions scores:transverse dimension (TD) indicating weight and chest circumference; length dimension (LD) indicating height and sitting height;transverse-length ratio dimension (TLD) indicating chest circumference-height ratio, chest circumference-sitting height and chest circumference-low limb ratio; proportion dimension (PD) indicating sitting height-low limb ratio. The whole dimension (WD) indicating the whole body shape was showed by the average of four dimensions scores. Four dimensions and WD scores were approximately 80 in children and adolescents with normal weight, and higher than those of overweight, obesity, and underweight (all P-values〈0.001). Areas under ROC of overweight and obesity compared with normal weight ranged from 0.88 to 1.00 for scores of TD, TLD, and WD. Conclusion The objective measure which included four dimensions was explored, and TD, TLD, and WD had significant discrimination power. 展开更多
关键词 Objective measure Body shape Children and adolescents
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A method to measure the rice kernel chalkiness objectively 被引量:1
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作者 XIAO Langto LIN Wanhuang LI Donghui HONG Bin Key Lab of Phytohoromones,Hunan Agri Univ,Changsha 410128 Computer Center,Hunan Agri Univ,Changsha 410128,China 《Chinese Rice Research Newsletter》 2001年第1期12-13,共2页
Rice kernel chalkiness is an impor-tant quality character.Being the un-transparent portions in grain en-dosperm,chalkiness iS always mea-sured by some subjective eye-judgingmethods domestically and interna-tionally.Re... Rice kernel chalkiness is an impor-tant quality character.Being the un-transparent portions in grain en-dosperm,chalkiness iS always mea-sured by some subjective eye-judgingmethods domestically and interna-tionally.Results measured by suchmethods aye subjective,inaccurate,and unstable.This research is in- 展开更多
关键词 area MARK A method to measure the rice kernel chalkiness objectively
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A systematic review of objective burn scar measurements 被引量:14
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作者 Kwang Chear Lee Janine Dretzke +2 位作者 Liam Grover Ann Logan Naiem Moiemen 《Burns & Trauma》 SCIE 2016年第2期90-122,共33页
Background:Problematic scarring remains a challenging aspect to address in the treatment of burns and can significantly affect the quality of life of the burn survivor.At present,there are few treatments available in ... Background:Problematic scarring remains a challenging aspect to address in the treatment of burns and can significantly affect the quality of life of the burn survivor.At present,there are few treatments available in the clinic to control adverse scarring,but experimental pharmacological anti-scarring strategies are now beginning to emerge.Their comparative success must be based on objective measurements of scarring,yet currently the clinical assessment of scars is not carried out systematically and is mostly based on subjective review of patients.However,several techniques and devices are being introduced that allow objective analysis of the burn scar.The aim of this article is to evaluate various objective measurement tools currently available and recommend a useful panel that is suitable for use in clinical trials of anti-scarring therapies.Methods:A systematic literature search was done using the Web of Science,PubMed and Cochrane databases.The identified devices were then classified and grouped according to the parameters they measured.The tools were then compared and assessed in terms of inter-and intra-rater reproducibility,ease of use and cost.Results:After duplicates were removed,5062 articles were obtained in the search.After further screening,157 articles which utilised objective burn scar measurement systems or tools were obtained.The scar measurement devices can be broadly classified into those measuring colour,metric variables,texture,biomechanical properties and pathophysiological disturbances.Conclusions:Objective scar measurement tools allow the accurate and reproducible evaluation of scars,which is important for both clinical and scientific use.However,studies to evaluate their relative performance and merits of these tools are scarce,and there remain factors,such as itch and pain,which cannot be measured objectively.On reviewing the available evidence,a panel of devices for objective scar measurement is recommended consisting of the 3D cameras(Eykona/Lifeviz/Vectra H1)for surface area and volume,DSM I colorimeter for colour,Dermascan high-frequency ultrasound for scar thickness and Cutometer for skin elasticity and pliability. 展开更多
关键词 Scar measurement BURN Objective measurement 3D camera Laser imaging High-frequency ultrasound image COLORIMETER Cutometer
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High-speed three-dimensional shape measurement with inner shifting-phase fringe projection profilometry 被引量:6
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作者 Shichao Yang Hanlin Huang +3 位作者 Gaoxu Wu Yanxue Wu Tian Yang Fei Liu 《Chinese Optics Letters》 SCIE EI CAS CSCD 2022年第11期78-84,共7页
Fringe projection profilometry(FPP)has been extensively studied in the field of three-dimensional(3D)measurement.Although FPP always uses high-frequency fringes to ensure high measurement accuracy,too many patterns ar... Fringe projection profilometry(FPP)has been extensively studied in the field of three-dimensional(3D)measurement.Although FPP always uses high-frequency fringes to ensure high measurement accuracy,too many patterns are projected to unwrap the phase,which affects the speed of 3D reconstruction.We propose a high-speed 3D shape measurement method using only three high-frequency inner shifting-phase patterns(70 periods),which satisfies both high precision and high measuring speed requirements.Besides,our proposed method obtains the wrapped phase and the fringe order simultaneously without any other information and constraints.The proposed method has successfully reconstructed moving objects with high speed at the camera's full frame rate(1700 frames per second). 展开更多
关键词 fringe projection profilometry high-speed 3D measurement inner shifting-phase dynamic object measurement
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Performance Measurement and Faculty Pay 被引量:1
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作者 LUO Pin-liang, RUI Ming-jie Management School, Fudan University, Shanghai 200433, China 《Systems Science and Systems Engineering》 CSCD 2002年第1期61-71,共11页
In classic agency models, first best efficiency can′t be achieved due to the trade-off between risk and incentives except that agency is risk neutral. Whereas if the principal′s objective is not contractible, an alt... In classic agency models, first best efficiency can′t be achieved due to the trade-off between risk and incentives except that agency is risk neutral. Whereas if the principal′s objective is not contractible, an alternative objective performance measurement which is contractible is always proposed. However, if the reaction of this objective performance measurement to agency′s effort differs from that of the principal′s objective, the agent would game performance measures, which leads to loss of efficiency, even if agency is risk neutral. By adding subjective weights on objective measures, or combination of subjective performance measurement with objective performance measurement, efficiency can be regained. Implications for faculty pay are also discussed. 展开更多
关键词 agency theory objective performance measurement subjective performance measurement faculty pay
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A RNN-based objective video quality measurement 被引量:1
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作者 黄轩 张荣 庞建新 《Chinese Optics Letters》 SCIE EI CAS CSCD 2009年第11期1004-1006,共3页
Technology used to automatically assess video quality plays a significant role in video processing areas. Because of the complexity of video media, there are great limitations to assess video quality with only one fac... Technology used to automatically assess video quality plays a significant role in video processing areas. Because of the complexity of video media, there are great limitations to assess video quality with only one factor. We propose a new method using artificial random neural networks (RNNs) with motion evaluation as an estimation of perceived visual distortion. The results are obtained through a nonlinear fitting procedure and well correlated with human perception. Compared with other methods, the proposed method performs more adaptable and accurate predictions. 展开更多
关键词 RNN SSIM A RNN-based objective video quality measurement PSNR DMOS
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Objective visual performance evaluation with visual evoked potential measurements based on an adaptive optics system 被引量:1
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作者 Yanrong Yang Junlei Zhao +4 位作者 Haoxin Zhao Fei Xiao Jiaxin Xie Wiejun Liu Yun Dai 《Chinese Optics Letters》 SCIE EI CAS CSCD 2018年第5期82-86,共5页
An objective visual performance evaluation with visual evoked potential (VEP) measurements was first inte- grated into an adaptive optics (AO) system. The optical and neural limits to vision can be bypassed throug... An objective visual performance evaluation with visual evoked potential (VEP) measurements was first inte- grated into an adaptive optics (AO) system. The optical and neural limits to vision can be bypassed through this system. Visual performance can be measured electrophysiologically with VEP, which reflects the objective func- tion from the retina to the primary visual cortex. The VEP ts without and with AO correction were preliminarily carried out using this system, demonstrating the great potential of this system in the objective visual performance evaluation. The new system will provide the necessary technique and equipment support for the further study of human visual function. 展开更多
关键词 VEP AO Objective visual performance evaluation with visual evoked potential measurements based on an adaptive optics system PSF
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Measurement of out-of-plane deformation of curved objects with digital speckle pattern interferometry 被引量:1
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作者 Pengfei Li Ping Cai +2 位作者 Jun Long Chiyue Liu Hao Yan 《Chinese Optics Letters》 SCIE EI CAS CSCD 2018年第11期40-46,共7页
Digital speckle pattern interferometry (DSPI) is a high-precision deformation t technique for planar objects. However, for curved objects, the three-dimensional (3D) shape information is needed in order to obtain ... Digital speckle pattern interferometry (DSPI) is a high-precision deformation t technique for planar objects. However, for curved objects, the three-dimensional (3D) shape information is needed in order to obtain correct deformation measurement in DSPI. Thus, combined shape and deformation measurement techniques of DSPI have been proposed. However, the current techniques are either complex in setup or complicated in operation. Furthermore, the operations of some techniques are too slow for real-time measurement. In this work, we propose a DSPI technique for both 3D shape and out-of-plane deformation measurement. Compared with current techniques, the proposed technique is simple in both setup and operation and is capable of fast deformation measurement. Theoretical analysis and experiments are performed. For a cylinder surface with an arch height of 9 mm, the error of out-of-plane deformation measurement is less than 0.15 μm. The effectiveness of the proposed scheme is verified. 展开更多
关键词 measurement of out-of-plane deformation of curved objects with digital speckle pattern interferometry
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3D shape measurement of larger complex objects based on fringe cycle correction
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作者 伏燕军 杨杰 +1 位作者 王志刚 吴海涛 《Chinese Optics Letters》 SCIE EI CAS CSCD 2014年第12期42-47,共6页
The grating fringe on the reference plane is broadened in the intersecting axis system because of oblique-angle projection. In order to solve this problem, we study the theoretical model of the temporal phase unwrappi... The grating fringe on the reference plane is broadened in the intersecting axis system because of oblique-angle projection. In order to solve this problem, we study the theoretical model of the temporal phase unwrapping method based on the fringe cycle correction. We also study the 3D shape measurement theoretical model of the larger complex objects after considering the coordinate deviation and lens distortion. Experimental results demonstrate that the fringe cycle on the reference plane can be corrected to a constant value, the lens distortion can be corrected, and 3D shape of larger complex objects can be accurately measured. 展开更多
关键词 shape measurement of larger complex objects based on fringe cycle correction CYCLE CCD
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An objective method for color vision deficiencies measurement based on visual evoked potential
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作者 熊凯 侯民贤 叶关荣 《Chinese Optics Letters》 SCIE EI CAS CSCD 2005年第7期432-434,共3页
The equi-luminance of color stimulus in normal subjects is characterized by L-cone and M-cone activation in retina. For the protanopes and deuternopes, only the activations of one relevant remaining cone type should b... The equi-luminance of color stimulus in normal subjects is characterized by L-cone and M-cone activation in retina. For the protanopes and deuternopes, only the activations of one relevant remaining cone type should be considered. The equi-luminance turning curve was established for the recorded visual evoked potentials (VEPs) of the luminance changes of the red and green color stimulus, and the position of the equi-luminance was used to define the kind and degree of color vision deficiencies. In the test of 47 volunteers we got the VEP traces and the equi-luminance turning curves, which was in accordance with the judgment by the pseudoisochromatic plate used in clinic. The method fulfills the objective and quantitative requirements in color vision deficiencies test. 展开更多
关键词 An objective method for color vision deficiencies measurement based on visual evoked potential VEP
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Comparison of human face matching behavior and computational image similarity measure 被引量:3
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作者 CHEN WenFeng LIU ChangHong +1 位作者 LANDER Karen FU XiaoLan 《Science in China(Series F)》 2009年第2期316-321,共6页
Computational similarity measures have been evaluated in a variety of ways, but few of the validated computational measures are based on a high-level, cognitive criterion of objective similarity. In this paper, we eva... Computational similarity measures have been evaluated in a variety of ways, but few of the validated computational measures are based on a high-level, cognitive criterion of objective similarity. In this paper, we evaluate two popular objective similarity measures by comparing them with face matching performance in human observers. The results suggest that these measures are still limited in predicting human behavior, especially in rejection behavior, but objective measure taking advantage of global and local face characteristics may improve the prediction. It is also suggested that human may set different criterions for“hit” and “rejection”and this may provide implications for biologically-inspired computational systems. 展开更多
关键词 image similarity human behaviour face matching objective measure subjective measure
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Use of land's cooperative object to estimate UAV's pose for autonomous landing 被引量:9
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作者 Xu Guili Qi Xiaopeng +3 位作者 Zeng Qinghua Tian Yupeng Guo Ruipeng Wang Biao 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2013年第6期1498-1505,共8页
The research of unmanned aerial vehicles'(UAVs')autonomy navigation and landing guidance with computer vision has important signifcance.However,because of the image blurring,the position of the cooperative points ... The research of unmanned aerial vehicles'(UAVs')autonomy navigation and landing guidance with computer vision has important signifcance.However,because of the image blurring,the position of the cooperative points cannot be obtained accurately,and the pose estimation algorithms based on the feature points have low precision.In this research,the pose estimation algorithm of UAV is proposed based on feature lines of the cooperative object for autonomous landing.This method uses the actual shape of the cooperative-target on ground and the principle of vanishing line.Roll angle is calculated from the vanishing line.Yaw angle is calculated from the location of the target in the image.Finally,the remaining extrinsic parameters are calculated by the coordinates transformation.Experimental results show that the pose estimation algorithm based on line feature has a higher precision and is more reliable than the pose estimation algorithm based on points feature.Moreover,the error of the algorithm we proposed is small enough when the UAV is near to the landing strip,and it can meet the basic requirements of UAV's autonomous landing. 展开更多
关键词 Computer vision Cooperative object Landing Position measurement UAV Vanishing line
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Which objective emergency department parameters leads to expedited intervention in patients with acute urinary tract calculi
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作者 Zachary Kranz Greggory Peifer +2 位作者 Matthew Rohloff Thomas Maatman Kenneth Shockley 《Current Urology》 2022年第1期1-4,共4页
Objectives:To retrospectively determine which objective measurements had an increased likelihood of requiring immediate surgical intervention in patients presenting to the emergency department(ED)with acute ureteral c... Objectives:To retrospectively determine which objective measurements had an increased likelihood of requiring immediate surgical intervention in patients presenting to the emergency department(ED)with acute ureteral calculi.Materials and methods:Employing our institution's electronic medical record system,we conducted a retrospective cohort study of 4366 patients who presented to the ED with an acute ureteral calculus over an 8-year period.Data consisting of relevant demographic information,vital signs,laboratory parameters,and interventional history was obtained and analyzed.Results:This study consisted of 4366 patients presenting to the ED with acute ureteral calculi,of whom 312(7%)required a procedure prior to being discharged.Of these 312 patients,290(6.6%)underwent cystoscopy with ureteral stent placement and 22(0.5%)were sent to interventional radiology for percutaneous nephrostomy tube placement.Patients who tested positive for nitrites in their urine had a relative risk of 3.48 of receiving intervention when compared to the nitrite negative group.Conclusions:Through this retrospective cohort study,we were able to find what objective measurements were associated with an increased need for immediate surgical intervention in patients who presented to the ED with acute ureteral calculi.With this data,urologists can be better equipped to identify the patients that present in the emergency setting that will require urgent intervention. 展开更多
关键词 CYSTOSCOPY Emergent surgical intervention Objective measurements Ureteral calculi Urinary nitrates
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