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The Jamaica Handheld Ultrasound Project:a novel longitudinal point-of-care ultrasound curriculum in a resource-limited setting
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作者 Maxime Montour Pranali Sheth +16 位作者 Steve Foo Simone French Tawanda Jones Giselle Watt Brian Kohen Aamir Bandagi Ariella Gartenberg Michael Halperin Trudy-Ann Johnson-Hylton Jason Ifill Alyssia McEwan Jonathan Maik Michelle Montenegro Rie Seu Nicole Leonard-shiu Hugh Wong Trevor Dixon 《World Journal of Emergency Medicine》 2025年第3期262-265,共4页
Point-of-care ultrasound(POCUS) is recognized as a valuable diagnostic tool,especially in resourcelimited settings(RLS).POCUS provides rapid diagnostic information that enables health professionals to make critical de... Point-of-care ultrasound(POCUS) is recognized as a valuable diagnostic tool,especially in resourcelimited settings(RLS).POCUS provides rapid diagnostic information that enables health professionals to make critical decisions at the bedside.^([1]) Despite the welldocumented benefits of POCUS,access to longitudinal,comprehensive training programs and a lack of trainee feedback are barriers to the widespread use of this technology in such settings.^([2]) 展开更多
关键词 health professionals point care ultrasound curriculum technology training feedback Jamaica handheld ultrasound resource limited settings longitudinal
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Design of handheld terminal for shock wave pressure measurement system
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作者 石晓丹 夏永乐 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2015年第2期169-174,共6页
Considering that it is difficult to monitor the measurement system and amend the test parameters on the scene in shock wave overpressure measurement and it is inconvenient to operate and carry traditional PC in outdoo... Considering that it is difficult to monitor the measurement system and amend the test parameters on the scene in shock wave overpressure measurement and it is inconvenient to operate and carry traditional PC in outdoor experiments, a new handheld terminal for shock wave pressure measurement system based on ARM is designed, The handheld terminal, whose ap- plication program is developed by the software of Qt, can control the measurement system by Wi-Fi and perform the functions of monitoring the system state, transmitting the data by wireless and displaying waveforms. To prevent data loss, USB inter- face is designed to read the data The test results show that the designed handheld terminal has good stability and reliability in several explosion experiments. 展开更多
关键词 shock wave handheld terminal QT
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Screening of unknown atrial fibrillation through handheld device in the elderly 被引量:3
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作者 Francesco Rivezzi Riccardo Vio +8 位作者 Claudio Bilato Leopoldo Pagliani Giampaolo Pasquetto Salvatore Saccà Roberto Verlato Federico Migliore Sabino Iliceto Vito Bossone Emanuele Bertaglia 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2020年第8期495-501,共7页
Objective To estimate the prevalence of unknown atrial fibrillation(AF)in the elderly population of the Veneto Region,Italy.Methods 1820 patients aged≥65 years with no history of AF and not anticoagulated were enroll... Objective To estimate the prevalence of unknown atrial fibrillation(AF)in the elderly population of the Veneto Region,Italy.Methods 1820 patients aged≥65 years with no history of AF and not anticoagulated were enrolled in primary-care settings.They underwent an opportunistic electrocardiogram screening with a handheld device(My Diagnostick)designed to specifically detect AF.The electrocardiogram recordings were reviewed by the researchers,who confirmed the presence of AF.Results The device detected an arrhythmia in 143 patients,which was confirmed as AF in 101/143(70.6%),with an overall prevalence of AF of 5.5%(101/1820).Prevalence of unknown AF resulted in 3.6%in patients aged 65–74 years,and 7.5%in patients age 75 or older,and increased according to CHA2 DS2-VASc score:3.5%in patients with a score of 1 or 2,5.6%in patients with a score of 3,7.0%in patients with a score of 4,and 7.2%in patients with a score≥5.The detection rate was significantly higher in patients with mild symptoms compared to asymptomatic counterparts(24.1%vs.4.0%,P<0.0001).At multivariate analysis,congestive heart failure and age≥75 years-old were independent predictors for screen-detected AF.Conclusions An opportunistic screening with handheld device revealed an unexpectedly high prevalence of unknown AF in elderly patients with mild symptoms.Prevalence increased with age and CHA2DS2-VASc score. 展开更多
关键词 Atrial fibrillation handheld electrocardiogram Primary care SCREENING Stroke prevention
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A new handheld fundus camera combined with visual artificial intelligence facilitates diabetic retinopathy screening 被引量:4
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作者 Shang Ruan Yang Liu +7 位作者 Wei-Ting Hu Hui-Xun Jia Shan-Shan Wang Min-Lu Song Meng-Xi Shen Da-Wei Luo Tao Ye Feng-Hua Wang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2022年第4期620-627,共8页
AIM: To explore the performance in diabetic retinopathy(DR) screening of artificial intelligence(AI) system by evaluating the image quality of a handheld Optomed Aurora fundus camera in comparison to traditional table... AIM: To explore the performance in diabetic retinopathy(DR) screening of artificial intelligence(AI) system by evaluating the image quality of a handheld Optomed Aurora fundus camera in comparison to traditional tabletop fundus cameras and the diagnostic accuracy of DR of the two modalities. METHODS: Overall, 630 eyes were included from three centers and screened by a handheld camera(Aurora, Optomed, Oulu, Finland) and a table-top camera. Image quality was graded by three masked and experienced ophthalmologists. The diagnostic accuracy of the handheld camera and AI system was evaluated in assessing DR lesions and referable DR.RESULTS: Under nonmydriasis status, the handheld fundus camera had better image quality in centration, clarity, and visible range(1.47, 1.48, and 1.40) than conventional tabletop cameras(1.30, 1.28, and 1.18;P<0.001). Detection of retinal hemorrhage, hard exudation,and macular edema were comparable between the two modalities, in principle, with the area under the curve of the handheld fundus camera slightly lower. The sensitivity and specificity for the detection of referable DR with the handheld camera were 82.1%(95%CI: 72.1%-92.2%) and 97.4%(95%CI: 95.4%-99.5%), respectively. The performance of AI detection of DR using the Phoebus Algorithm was satisfactory;however, Phoebus showed a high sensitivity(88.2%, 95%CI: 79.4%-97.1%) and low specificity(40.7%, 95%CI: 34.1%-47.2%) when detecting referable DR.CONCLUSION: The handheld Aurora fundus camera combined with autonomous AI system is well-suited in DR screening without mydriasis because of its high sensitivity of DR detection as well as its image quality, but its specificity needs to be improved with better modeling of the data. Use of this new system is safe and effective in the detection of referable DR in real world practice. 展开更多
关键词 diabetic retinopathy image quality handheld camera artificial intelligence
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A comparison of handheld and standard ultrasound in Swiss medical students 被引量:1
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作者 Mark Slader Hayley Young +5 位作者 Margot Barker Kylie Prentice Katherine Bogaard Charlene Yuan Soheil Saadat Shadi Lahham 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2022年第2期85-90,共6页
BACKGROUND:The use of ultrasound(US)within healthcare has inspired the development of new US technology.There have been few studies comparing the use of handheld US to standard US for medical education.This research a... BACKGROUND:The use of ultrasound(US)within healthcare has inspired the development of new US technology.There have been few studies comparing the use of handheld US to standard US for medical education.This research aims to determine whether a handheld US device can provide a comparable primary learning experience to that of a standard US machine.METHODS:Over two days of instruction,participants were taught and evaluated on core US fundamentals.The standard group received instruction on standard US machines,while the handheld group received instruction on handheld US devices.Participants completed a qualitative survey regarding their experience.Six hundred and four images were obtained and graded by two emergency medicine physicians.RESULTS:A total of 119 Swiss medical students were enrolled in our study.There was no statistically significant difference in the US assessment measurements,except for faster endpoint septal separation(EPSS)vascular setup time in the handheld group(P=0.001).There was no statistically significant difference in participants’perceived difficulty of US learning(P=0.198),comfort level(P=0.188),or self-estimated capability to perform US in the future(P=0.442).There was no statistically significant difference in the percentage of correctly obtained images(P=0.211)or images that were clinically useful(P=0.256).The median quality score of images obtained by the standard group was eight compared to seven in handheld group(P<0.01).CONCLUSION:Our data suggest a handheld US machine can perform as well as a standard US machine as an educational tool despite sacrifices in image quality. 展开更多
关键词 handheld ultrasound Ultrasound education Switzerland Medical education
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Assessment of handheld mobile terrestrial laser scanning for estimating tree parameters
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作者 Cornelis Stal Jeff rey Verbeurgt +1 位作者 Lars De Sloover Alain De Wulf 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第4期1503-1513,共11页
Sustainable forest management heavily relies on the accurate estimation of tree parameters.Among others,the diameter at breast height(DBH) is important for extracting the volume and mass of an individual tree.For syst... Sustainable forest management heavily relies on the accurate estimation of tree parameters.Among others,the diameter at breast height(DBH) is important for extracting the volume and mass of an individual tree.For systematically estimating the volume of entire plots,airborne laser scanning(ALS) data are used.The estimation model is frequently calibrated using manual DBH measurements or static terrestrial laser scans(STLS) of sample plots.Although reliable,this method is time-consuming,which greatly hampers its use.Here,a handheld mobile terrestrial laser scanning(HMTLS) was demonstrated to be a useful alternative technique to precisely and efficiently calculate DBH.Different data acquisition techniques were applied at a sample plot,then the resulting parameters were comparatively analysed.The calculated DBH values were comparable to the manual measurements for HMTLS,STLS,and ALS data sets.Given the comparability of the extracted parameters,with a reduced point density of HTMLS compared to STLS data,and the reasonable increase of performance,with a reduction of acquisition time with a factor of5 compared to conventional STLS techniques and a factor of3 compared to manual measurements,HMTLS is considered a useful alternative technique. 展开更多
关键词 Forest inventory DBH Airborne laser scanning Terrestrial laser scanning handheld mobile laser scanning Point cloud processing
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An Analysis on Position Estimation, Drifting and Accumulated Error Accuracy during 3D Tracking in Electronic Handheld Devices
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作者 Shanjidah Akhter Pahlwan Rabiul Islam +2 位作者 Latifun Ahsin Bhuiyan Mehedi Hasan A. F. M. Saifuddin Saif 《Journal of Computer and Communications》 2018年第4期65-75,共11页
This work focuses on a brief discussion of new concepts of using smartphone sensors for 3D painting in virtual or augmented reality. Motivation of this research comes from the idea of using different types of sensors ... This work focuses on a brief discussion of new concepts of using smartphone sensors for 3D painting in virtual or augmented reality. Motivation of this research comes from the idea of using different types of sensors which exist in our smartphones such as accelerometer, gyroscope, magnetometer etc. to track the position for painting in virtual reality, like Google Tilt Brush, but cost effectively. Research studies till date on estimating position and localization and tracking have been thoroughly reviewed to find the appropriate algorithm which will provide accurate result with minimum drift error. Sensor fusion, Inertial Measurement Unit (IMU), MEMS inertial sensor, Kalman filter based global translational localization systems are studied. It is observed, prevailing approaches consist issues such as stability, random bias drift, noisy acceleration output, position estimation error, robustness or accuracy, cost effectiveness etc. Moreover, issues with motions that do not follow laws of physics, bandwidth, restrictive nature of assumptions, scale optimization for large space are noticed as well. Advantages of such smartphone sensor based position estimation approaches include, less memory demand, very fast operation, making them well suited for real time problems and embedded systems. Being independent of the size of the system, they can work effectively for high dimensional systems as well. Through study of these approaches it is observed, extended Kalman filter gives the highest accuracy with reduced requirement of excess hardware during tracking. It renders better and faster result when used in accelerometer sensor. With the aid of various software, error accuracy can be increased further as well. 展开更多
关键词 3D Tracking Error ACCURACY Extended KALMAN Filter handheld Device Position Estimation Sensor Virtual REALITY AUGMENTED REALITY
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Handheld 3D Scanner for Small Objects Using Kinect
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作者 Chia-Chi Hsu Chung-Lin Huang 《Journal of Electronic Science and Technology》 CAS CSCD 2016年第4期377-383,共7页
This paper presents a handheld 3D vision-based scanner for small objects by using Kinect. It is different from the previous color-glove-based approaches which require segmenting the target object. First, we eliminate ... This paper presents a handheld 3D vision-based scanner for small objects by using Kinect. It is different from the previous color-glove-based approaches which require segmenting the target object. First, we eliminate the noises and the outliers caused by holding hands. Second, we apply Kinect-fusion algorithm and truncated signed distance function (TSDF) to represent 3D surfaces. Third, we propose a modified integration strategy to eliminate the hand effect. Fourth, we take advantage of the parallel computation of GPUs for real-time operation. The major contributions of this paper are (1) the registration precision is improved, (2) the oflline amendment and loop closure operation are not required, and (3) concave 3D object reconstruction is feasible. 展开更多
关键词 handheld 3D scanning Kinect-fusion Truncated signed distance function (TSDF).
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Role of Wireless Handheld Technology by Nurses in Healthcare Environment
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作者 Abdul Hafeez-Baig Raj Gururajan 《Computer Technology and Application》 2012年第8期550-557,共8页
One of the emerging technologies is wireless handheld technology. Implication of these devices is enormous for business community and healthcare domain is not an exception to this phenomena. This research paper provid... One of the emerging technologies is wireless handheld technology. Implication of these devices is enormous for business community and healthcare domain is not an exception to this phenomena. This research paper provides some useful findings about the use of PDA's in the healthcare environment through actual usage of PDA in the healthcare ward. A qualitative and quantitative approach is adopted to explore these phenomena due to the exploratory nature of the research. Findings of this study identify some of the motivators and issues associated with the wireless handheld technology in healthcare environment. Furthermore, it is also found that these wireless handheld devices can help to improve the quality of care through better decision making processes. This study is limited to only one sate of Australian and further research is needed to see the implication of the findings to wider community and other domains in the Australian environment. 展开更多
关键词 Smart technology ICT (information and communication technology) wireless handheld devices healthcare adoption andactual use decision.
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V_(2)CT_(x) MXene-powered handheld SERS biosensor for the viral antigen test
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作者 Meng-Nan Li Bo Cao +10 位作者 Yan-Ling Wang Hang Zhou Hai-Xu Yao Yuan Gao Xi-Wei Zhuang Jian-Lei Liu Chi-Jia Zeng Susan Zhou Da-Ling Zhu Jian Ma Fei-Yun Cui 《Rare Metals》 2025年第9期6442-6455,共14页
The intrinsic property of MXenes to adsorb dyes with high Raman scattering cross-sections makes them promising candidates for surface-enhanced Raman scattering(SERS)biosensors.In the study,we report a vanadium carbide... The intrinsic property of MXenes to adsorb dyes with high Raman scattering cross-sections makes them promising candidates for surface-enhanced Raman scattering(SERS)biosensors.In the study,we report a vanadium carbide MXene(V_(2)CT_(x))-based SERS biosensor tag,V_(2)CT_(x)@Thi(thionine)@Au NPs(gold nanoparticles)-Ab(antibody),owing to its large interlayer spacing and superior dye adsorption capacity.The tag V_(2)CT_(x)@Thi@Au NPs-Ab was fully characterized and validated,demonstrating a significantly enhanced Raman signal through both electromagnetic and chemical enhancement mechanisms.Using a handheld Raman spectrometer as a readout tool,the developed handheld SERS biosensor was successfully applied for the detection of viral antigens.The biosensor exhibited excellent linearity(1.562–100 nM)and achieved a low limit of detection(LOD)1.562 nM.Moreover,the biosensor demonstrated good selectivity and stability for detecting the target S protein in saliva samples.Our study highlights the potential of V_(2)CT_(x)MXene as a powerful material for handheld SERS biosensors,paving the way for portable and efficient viral diagnostics. 展开更多
关键词 Surface-enhanced Raman scattering(SERS) MXenes Vanadium carbide(V_(2)CT_(x)) Viral antigen handheld Raman detection
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手持控制器操作的上肢关节舒适性评估与作业优化研究
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作者 杨延璞 杨沁夏 +1 位作者 卓玥鸣 姬丽静 《西北工业大学学报》 北大核心 2025年第4期741-750,共10页
无人装备手持控制器的长时间操作易给作业人员带来上肢肌肉骨骼损伤风险,为提高手持控制器作业中人员的上肢关节舒适性,利用JACK人机工程分析软件进行数字人与作业场景建模,分别构建了关节力矩和角度的舒适度评估模型,研究了寰枕关节不... 无人装备手持控制器的长时间操作易给作业人员带来上肢肌肉骨骼损伤风险,为提高手持控制器作业中人员的上肢关节舒适性,利用JACK人机工程分析软件进行数字人与作业场景建模,分别构建了关节力矩和角度的舒适度评估模型,研究了寰枕关节不同前屈角度下的上肢关节舒适度变化关系,建立了手持控制器上肢姿态优化多目标函数,引入带精英策略的快速非支配排序遗传算法(nondominated sorting genetic algorithmⅡ,NSGA-Ⅱ)进行最优上肢姿态求解,获取手持控制器作业的最佳姿势并设计了辅助装置方案,进而引入直觉模糊数处理决策者在评估设计方案时的不确定与犹豫性,实现了最优姿态下手持控制器操作辅助装置设计方案优选。 展开更多
关键词 人机工效 上肢关节舒适性评估 多目标优化 直觉模糊数 手持控制器
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CTA与手持多普勒彩超在游离股前外侧皮瓣穿支定位中的价值及研究
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作者 张宏 邵蓉 +4 位作者 王军 范向达 王娟 张建伟 宋一丁 《中国现代药物应用》 2025年第6期51-54,共4页
目的探讨CT血管造影(CTA)与手持多普勒彩超在游离股前外侧穿支皮瓣修复头颈颌面部缺损的临床价值。方法50例行游离股前外侧穿支皮瓣修复的头颈颌面部恶性肿瘤切除术后缺损患者,根据术前定位方法不同分为A组和B组,每组25例。A组术前运用... 目的探讨CT血管造影(CTA)与手持多普勒彩超在游离股前外侧穿支皮瓣修复头颈颌面部缺损的临床价值。方法50例行游离股前外侧穿支皮瓣修复的头颈颌面部恶性肿瘤切除术后缺损患者,根据术前定位方法不同分为A组和B组,每组25例。A组术前运用CTA进行穿支血管定位,B组术前运用手持多普勒彩超进行穿支血管定位,根据定位穿支点对患者皮瓣进行术前设计及指导。比较两组患者的穿支血管吻合率、血管危象发生情况及手术时间。结果A组患者有24例穿支完全吻合,吻合率为96%(24/25),且皮瓣穿支定位准确率高,术后皮瓣全部存活,可明显缩短手术所用的时间。B组患者有22例探测到穿支,其中有3例患者术前探测到的穿支位置与术中切开后发现的穿支位置不一致,1例是来自股直肌表面发出的穿支,1例发现穿支来源于横支,并非降支,切取横支穿支皮瓣,1例术中发现穿支血管较细,穿支搏动无力,向上仔细寻找发现穿支来源于升支,并非降支;3例患者未探测到穿支,吻合率为76%(19/25)。A组穿支血管吻合率明显高于B组,差异有统计学意义(χ^(2)=4.153,P<0.05)。术后,A组未发生血管危象,B组有1例发生动脉危象,1例发生静脉危象,经急诊手术抢救后,2例皮瓣均成活,其余皮瓣未出现坏死。A组手术时间(100±20)min短于B组的(150±15)min,差异有统计学意义(P<0.05)。结论术前应用CTA检查可精准定位游离股前外侧皮瓣穿支,可提高穿支定位的准确率,为术前设计和术中切取皮瓣提供指导,明显缩短取瓣时间,减少出血量,提高皮瓣移植成功率,值得临床大力推广。 展开更多
关键词 CT血管造影 手持多普勒彩超 股前外侧穿支皮瓣 修复重建 头颈颌面部缺损修复
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用于物化探测网布设的GPS航点生成方法与实现
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作者 张琪 刘多朝 张万仁 《物探与化探》 2025年第1期200-205,共6页
测网布设是物化探勘查的先行工作内容,手持GPS的广泛应用给中小比例尺物化探野外勘查的导航定位带来了极大的便利。本文从坐标系转换的基础理论出发,面向物化探勘查中规则和不规则两类设计测网,提出了一种可生成大批量航点的方法,并编... 测网布设是物化探勘查的先行工作内容,手持GPS的广泛应用给中小比例尺物化探野外勘查的导航定位带来了极大的便利。本文从坐标系转换的基础理论出发,面向物化探勘查中规则和不规则两类设计测网,提出了一种可生成大批量航点的方法,并编制了相应的计算软件。该软件界面设计简洁,操作便利,无须借助第三方工具软件即可快捷地生成适合于重磁电测量、土壤测量、水系沉积物测量等方法的设计测网,用于野外作业时导航。 展开更多
关键词 坐标系 WGS-84 手持GPS 测网布设 规则网 不规则网
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手持近红外光谱仪用于烟叶中烟碱含量现场非破坏定量检测方法研究
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作者 林云 翟生 +4 位作者 张军 詹映 彭云发 罗海燕 李俊鑫 《分析测试学报》 北大核心 2025年第10期2107-2112,共6页
为了提高手持式近红外光谱仪在烟叶烟碱含量检测中的准确性,该文提出了一种优化的定量检测方法。首先利用手持式近红外光谱仪采集烟叶光谱数据,并对其进行一阶导数预处理;然后,通过非参数检验的最大信息探索方法提取非线性波长系数,并... 为了提高手持式近红外光谱仪在烟叶烟碱含量检测中的准确性,该文提出了一种优化的定量检测方法。首先利用手持式近红外光谱仪采集烟叶光谱数据,并对其进行一阶导数预处理;然后,通过非参数检验的最大信息探索方法提取非线性波长系数,并采用线性回归方法提取线性波长决定系数;接着结合相关系数边界决策阈值,使用多层感知算法将波长组合划分为线性波段和非线性波段,分别建立预测模型。最后,将各波段的预测结果通过不同权重系数进行组合,并与传统全波段偏最小二乘法建模结果进行对比分析。结果表明,基于组合波段的模型相关系数提高了6.57%,平均绝对误差降低了26.05%,平均相对误差降低了28.11%。该方法显著提升了模型的预测准确性,满足手持式近红外光谱仪对烟叶中烟碱含量快速、准确、无损检测的实际应用需求。 展开更多
关键词 手持式近红外光谱仪 烟碱含量 非参数检验 线性回归 多层感知
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融合手持三维激光和倾斜摄影数据的既有建筑现状测绘方法及应用分析
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作者 杜顺季 陈思如 赵新科 《测绘通报》 北大核心 2025年第S1期185-190,共6页
既有建筑的权属补充登记是近几年城市测绘的重点任务,但多数既有建筑存在缺失竣工图等问题,须开展现状测绘并绘制建筑现状图。目前主要采用全站仪等传统手段,存在效率低、可视化差、数据单一等不足。针对既有建筑权属登记与改造需求,提... 既有建筑的权属补充登记是近几年城市测绘的重点任务,但多数既有建筑存在缺失竣工图等问题,须开展现状测绘并绘制建筑现状图。目前主要采用全站仪等传统手段,存在效率低、可视化差、数据单一等不足。针对既有建筑权属登记与改造需求,提出手持三维激光点云与倾斜摄影模型融合的现状测绘方法。实例验证,平面中误差小于5 cm,满足房产测绘和建筑方案设计要求,作业效率提高3倍,可操作性强,为存量建筑测绘提供高效解决方案。 展开更多
关键词 手持三维激光扫描 倾斜摄影测量 点云融合 既有建筑测绘 精度分析
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基于手持激光雷达的人工侧柏纯林冠层空间互补性
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作者 胡蕾 刘茜紫 +3 位作者 耿燕 余世有 姜俊 陈玲 《北京林业大学学报》 北大核心 2025年第4期61-73,共13页
【目的】探讨手持激光雷达在冠层空间互补性研究中的适用性,分析冠层空间互补性的影响因素及其对单木生长量的影响,为优化侧柏纯林的林分结构并提高生产力提供参考。【方法】基于地面实测数据验证手持激光雷达点云数据的精度,评估其在... 【目的】探讨手持激光雷达在冠层空间互补性研究中的适用性,分析冠层空间互补性的影响因素及其对单木生长量的影响,为优化侧柏纯林的林分结构并提高生产力提供参考。【方法】基于地面实测数据验证手持激光雷达点云数据的精度,评估其在冠层空间互补性研究中的可行性;以邻域树木性状变异、邻体密度、土壤因子和地形因子为解释变量,运用线性相关分析和全子集回归模型探讨解释变量与冠层空间互补性之间的相关关系;采用结构方程模型解析冠层空间互补性在解释变量影响目标树生长量过程中的中介作用。【结果】(1)手持激光雷达提取的胸径、树高和冠幅与野外实测值呈显著正相关(P<0.001),表明其参数精度适用于冠层空间互补性研究。(2)树冠形状变异(P<0.001)、树冠大小变异(P<0.01)和树木高度变异(P<0.001)对冠层空间互补性具有显著的促进作用;株数密度(P<0.001)同样也具有显著正效应;坡向(P<0.05)与坡度(P<0.05)能显著影响冠层空间互补性;土壤全磷(P<0.05)、全钾(P<0.01)、有效磷(P<0.05)、有效钾(P<0.05)含量和土壤容重(P<0.05)均显著负向影响冠层空间互补性。全子集模型结果表明,邻域树木性状变异和土壤因子为冠层空间互补性变异的主要驱动因素,解释量分别占总解释量的40.75%和31.64%。(3)冠层空间互补性显著促进目标树胸径生长(P<0.01)。结构方程模型结果表明,邻域树木性状变异、邻体密度、土壤和地形因子均可通过冠层空间互补性间接影响目标树生长。【结论】冠层空间互补性在人工侧柏纯林中普遍存在,并受到生物和非生物因子的共同影响,这些因子通过冠层空间互补性间接促进了树木的生长。基于本研究结果,建议在种植侧柏时,应优先选择阴坡且土壤养分丰富的区域;对于已建成的人工侧柏纯林,可通过定期修剪侧柏、增加树木间垂直方向差异的方式促进胸径的生长。 展开更多
关键词 冠层空间互补性 胸径生长量 手持激光雷达 纯林 侧柏
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术中手持细胞级显微镜系统在甲状腺癌手术中的应用价值探索 被引量:1
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作者 饶良蜜 吴德林 +3 位作者 王子康 宛凌峰 耿瑞 马小鹏 《中国实用医药》 2025年第15期74-77,共4页
目的探讨手持细胞级显微镜系统(EndoSCell^(TM)系统)在甲状腺癌手术中的应用价值。方法选取9例行手术治疗的甲状腺癌患者,术中通过手持EndoSCell^(TM)系统实时扫描原发灶、喉返神经、气管及甲状旁腺等表面以观察肿瘤组织,通过荧光素钠... 目的探讨手持细胞级显微镜系统(EndoSCell^(TM)系统)在甲状腺癌手术中的应用价值。方法选取9例行手术治疗的甲状腺癌患者,术中通过手持EndoSCell^(TM)系统实时扫描原发灶、喉返神经、气管及甲状旁腺等表面以观察肿瘤组织,通过荧光素钠和亚甲蓝溶液对可疑区域染色,然后使用显微镜进行扫描。以术后常规病理为金标准,观察EndoSCell^(TM)系统扫描判断甲状腺癌原发灶的准确性;EndoSCell^(TM)系统扫描成像喉返神经、气管及甲状旁腺的成功率。结果9例患者的原发灶及重要结构均成功成像(100%),检测到1例气管浆膜残留癌和1例喉返神经外膜受累患者,经精准切除后保留功能结构。术后随访半年无并发症、复发及转移。结论手持EndoSCell^(TM)系统能实现细胞级实时检测,为侵袭性甲状腺癌精准切除提供客观依据,在R0切除基础上避免盲目扩大切除范围,该技术具有良好的临床应用前景。 展开更多
关键词 甲状腺癌 术中 手持细胞级显微镜系统 荧光成像技术
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Improvement of registration accuracy of a handheld augmented reality system for urban landscape simulation 被引量:4
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作者 Tomohiro Fukuda Tian Zhang Nobuyoshi Yabuki 《Frontiers of Architectural Research》 CSCD 2014年第4期386-397,共12页
The need for visual landscape assessment in large-scale projects for the evaluation of the effects of a particular project on the surrounding landscape has grown in recent years. Augmented reality (AR) has been cons... The need for visual landscape assessment in large-scale projects for the evaluation of the effects of a particular project on the surrounding landscape has grown in recent years. Augmented reality (AR) has been considered for use as a landscape simulation system in which a landscape assessment object created by 3D models is included in the present surroundings. With the use of this system, the time and the cost needed to perform a 3DCG modeling of present surroundings, which is a major issue in virtual reality, are drastically reduced. This research presents the development of a 3D maporiented handheld AR system that achieves geometric consistency using a 3D map to obtain position data instead of GPS, which has tow position information accuracy, particularly in urban areas. The new system also features a gyroscope sensor to obtain posture data and a video camera to capture live video of the present surroundings. All these components are mounted in a smartphone and can be used for urban landscape assessment. Registration accuracy is evaluated to simulate an urban landscape from a short- to a long-range scale. The latter involves a distance of approximately 2000 m. The developed AR system enables users to simulate a Landscape from multiple and longdistance viewpoints simultaneously and to walk around the viewpoint fields using only a smartphone. This result is the tolerance level of Landscape assessment. In conclusion, the proposed method is evaluated as feasible and effective. 展开更多
关键词 Landscape simulation Augmented reality handheld device Registration accuracy ASSESSMENT
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手持三维激光扫描仪在城市更新立面测量中的应用 被引量:2
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作者 王召泽 韩若愚 +1 位作者 赵智伟 路奇琛 《测绘通报》 北大核心 2025年第1期133-137,共5页
随着科技进步及不断演化,手持三维激光扫描仪作为一种高效、高精度的测绘仪器,近年来在各行各业得到了广泛关注和应用。本文针对采用传统仪器对城市更新过程中旧房改造立面测量作业效率低下,且复杂建筑物绘制难度大,精度难以保证等缺点... 随着科技进步及不断演化,手持三维激光扫描仪作为一种高效、高精度的测绘仪器,近年来在各行各业得到了广泛关注和应用。本文针对采用传统仪器对城市更新过程中旧房改造立面测量作业效率低下,且复杂建筑物绘制难度大,精度难以保证等缺点,探讨了手持三维激光扫描仪的技术特点、参数,并重点介绍城市更新旧房改造立面测量技术流程和应用案例分析,最后对手持三维激光扫描仪的应用前景进行展望。本文对提升城市更新旧房改造立面测量技术具有重要意义。 展开更多
关键词 手持三维激光扫描仪 建筑物立面测量 激光点云 数据采集 精度
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