lasers

激光器
  • 文章类型: Journal Article
    为了快速获得水稻植株表型性状,本研究提出了六种水稻表型特征的计算过程(例如,冠部直径,茎的周长,植物高度,表面积,volume,和投影叶面积)使用地面激光扫描(TLS)数据,并提出了水稻植株分耕数的提取方法。具体来说,第一次,我们设计并开发了一种基于PyQt5框架和Open3D库的三层体系结构的水稻植株自动表型提取工具。结果表明,测量值与提取值之间的线性确定系数(R2)在所选的四个验证特征中具有更好的可靠性。冠径均方根误差(RMSE),茎的周长,植物高度稳定在厘米水平,耕种者的数量低至1.63。冠径的相对均方根误差(RRMSE),植物高度,分till数保持在10%以内,茎周长为18.29%。此外,用户友好的自动提取工具可以有效地提取水稻植株的表型特征,为快速获取水稻植株点云的表型性状特征提供了方便的工具。然而,更多水稻植物样本数据支持的表型特征提取结果的比较和验证,以及精度算法的改进,仍然是我们未来研究的重点。该研究可为利用三维点云提取作物表型提供参考。
    To quickly obtain rice plant phenotypic traits, this study put forward the computational process of six rice phenotype features (e.g., crown diameter, perimeter of stem, plant height, surface area, volume, and projected leaf area) using terrestrial laser scanning (TLS) data, and proposed the extraction method for the tiller number of rice plants. Specifically, for the first time, we designed and developed an automated phenotype extraction tool for rice plants with a three-layer architecture based on the PyQt5 framework and Open3D library. The results show that the linear coefficients of determination (R2) between the measured values and the extracted values marked a better reliability among the selected four verification features. The root mean square error (RMSE) of crown diameter, perimeter of stem, and plant height is stable at the centimeter level, and that of the tiller number is as low as 1.63. The relative root mean squared error (RRMSE) of crown diameter, plant height, and tiller number stays within 10%, and that of perimeter of stem is 18.29%. In addition, the user-friendly automatic extraction tool can efficiently extract the phenotypic features of rice plant, and provide a convenient tool for quickly gaining phenotypic trait features of rice plant point clouds. However, the comparison and verification of phenotype feature extraction results supported by more rice plant sample data, as well as the improvement of accuracy algorithms, remain as the focus of our future research. The study can offer a reference for crop phenotype extraction using 3D point clouds.
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  • 文章类型: Journal Article
    从单源点云数据中提取毛竹参数具有局限性。在这篇文章中,提出了一种利用机载激光扫描(ALS)和地面激光扫描(TLS)点云数据提取毛竹参数的新方法。使用现场测量的曲线角点坐标和迭代最近点(ICP)算法,ALS和TLS点云对齐。考虑到ALS点分布的差异,TLS,和合并的点云,使用点云分割(PCS)算法从ALS点云分割出单个竹子植物,使用比较最短路径(CSP)方法从TLS和合并的点云中分割出单个竹子植物。圆柱拟合方法用于估计分段竹子植物的胸高直径(DBH)。通过将上述方法提取的竹子参数值与三个样地中的参考数据进行比较来计算精度。比较结果表明,通过使用合并后的数据,毛竹植物的检出率可达97.30%;估计竹高的R2提高到0.96以上,均方根误差(RMSE)从最多1.14m下降到0.35-0.48m,而DBH拟合的R2提高到0.97-0.99,RMSE从最多0.004m降低到0.001-0.003m。使用合并的点云数据显着提高了毛竹参数提取的精度。
    Extracting moso bamboo parameters from single-source point cloud data has limitations. In this article, a new approach for extracting moso bamboo parameters using airborne laser scanning (ALS) and terrestrial laser scanning (TLS) point cloud data is proposed. Using the field-surveyed coordinates of plot corner points and the Iterative Closest Point (ICP) algorithm, the ALS and TLS point clouds were aligned. Considering the difference in point distribution of ALS, TLS, and the merged point cloud, individual bamboo plants were segmented from the ALS point cloud using the point cloud segmentation (PCS) algorithm, and individual bamboo plants were segmented from the TLS and the merged point cloud using the comparative shortest-path (CSP) method. The cylinder fitting method was used to estimate the diameter at breast height (DBH) of the segmented bamboo plants. The accuracy was calculated by comparing the bamboo parameter values extracted by the above methods with reference data in three sample plots. The comparison results showed that by using the merged data, the detection rate of moso bamboo plants could reach up to 97.30%; the R2 of the estimated bamboo height was increased to above 0.96, and the root mean square error (RMSE) decreased from 1.14 m at most to a range of 0.35-0.48 m, while the R2 of the DBH fit was increased to a range of 0.97-0.99, and the RMSE decreased from 0.004 m at most to a range of 0.001-0.003 m. The accuracy of moso bamboo parameter extraction was significantly improved by using the merged point cloud data.
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  • 文章类型: Journal Article
    高级氧化工艺(AOPs)通过产生自由基物种,如羟基自由基,提供了有前途的消毒方法。超氧阴离子自由基,和羟基过氧,可以诱导氧化应激并使细菌细胞失活。光催化,AOP的一个子集,使用特定的电磁波长激活半导体。一种新颖的材料,Cu/Cu2O/CuO纳米粒子(NPs),是通过激光烧蚀协议合成的(使用1064nm波长的激光,以水为溶剂,能量范围为25、50和80mJ,持续10分钟)。以1.6、1.1和1°C/min的速率将靶从100°C烧结至800°C。Cu的复合相,CuO,Cu2O在368nm的可见光激发下显示出增强的光催化活性。Cu/Cu2O/CuONPs的大小有利于渗透到微生物中,从而提高消毒效果。这项研究有助于合成混合氧化铜,并探索它们作为清洁表面光催化剂的活化作用。电子和电化学性能在其他领域具有潜在的应用,如电容器材料。与前体相比,激光烧蚀方法可以改善Cu/Cu2O/CuONP的带隙吸收并增强催化性能。用Cu/Cu2O/CuO系统消毒大肠杆菌作为一个案例研究,证明了该方法在各种应用中的多功能性。包括对不同微生物的消毒,革兰氏阳性和革兰氏阴性。
    Advanced Oxidation Processes (AOPs) offer promising methods for disinfection by generating radical species like hydroxyl radicals, superoxide anion radicals, and hydroxy peroxyl, which can induce oxidative stress and deactivate bacterial cells. Photocatalysis, a subset of AOPs, activates a semiconductor using specific electromagnetic wavelengths. A novel material, Cu/Cu2O/CuO nanoparticles (NPs), was synthesized via a laser ablation protocol (using a 1064 nm wavelength laser with water as a solvent, with energy ranges of 25, 50, and 80 mJ for 10 min). The target was sintered from 100 °C to 800 °C at rates of 1.6, 1.1, and 1 °C/min. The composite phases of Cu, CuO, and Cu2O showed enhanced photocatalytic activity under visible-light excitation at 368 nm. The size of Cu/Cu2O/CuO NPs facilitates penetration into microorganisms, thereby improving the disinfection effect. This study contributes to synthesizing mixed copper oxides and exploring their activation as photocatalysts for cleaner surfaces. The electronic and electrochemical properties have potential applications in other fields, such as capacitor materials. The laser ablation method allowed for modification of the band gap absorption and enhancement of the catalytic properties in Cu/Cu2O/CuO NPs compared to precursors. The disinfection of E. coli with Cu/Cu2O/CuO systems serves as a case study demonstrating the methodology\'s versatility for various applications, including disinfection against different microorganisms, both Gram-positive and Gram-negative.
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  • 文章类型: Journal Article
    经胫骨截肢者肢体体积和形状的变化会影响承窝的贴合性和舒适性。精确测量残肢体积和形状并将其与舒适度相关联的能力可能有助于插座设计和整体护理的进步。这项工作设计并验证了一种新颖的3D激光扫描仪,可以测量残肢的体积和形状。该系统旨在提供准确和可重复的扫描,最小化扫描持续时间,并解释扫描过程中的肢体运动。首先使用具有已知形状的圆柱体对扫描仪进行验证。在静态条件下,平均体积误差为0.17%,对应于0.1毫米的径向空间分辨率。还对胫骨截肢者进行了肢体扫描,五次扫描的标准偏差为8.1ml(0.7%)。和46毫升(4%)的肢体体积的变化时,脱窝后15分钟的站立。
    Changes in limb volume and shape among transtibial amputees affects socket fit and comfort. The ability to accurately measure residual limb volume and shape and relate it to comfort could contribute to advances in socket design and overall care. This work designed and validated a novel 3D laser scanner that measures the volume and shape of residual limbs. The system was designed to provide accurate and repeatable scans, minimize scan duration, and account for limb motion during scans. The scanner was first validated using a cylindrical body with a known shape. Mean volumetric errors of 0.17% were found under static conditions, corresponding to a radial spatial resolution of 0.1 mm. Limb scans were also performed on a transtibial amputee and yielded a standard deviation of 8.1 ml (0.7%) across five scans, and a 46 ml (4%) change in limb volume when the socket was doffed after 15 minutes of standing.
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  • 文章类型: Journal Article
    组织生物力学特性,比如弹性,与组织健康有关。光学相干弹性成像根据组织的弹性产生图像,但是它的性能受到所用激光功率的限制,工作距离,和激励方法。
    我们开发了一种新方法来重建长工作距离的弹性对比图像,只有低强度的照明,并通过非接触声波激励。
    我们将单光子测振法和量子参数模式分类(QPMS)结合起来,以测量单光子水平的振荡反向散射信号,并得出幻像\'相对弹性。
    我们在由不同浓度和因此硬度的对比切片组成的组织模拟体模上测试了我们的系统。我们的结果表明,随着驱动声频率的扫描,体模的振动响应被映射到光子计数直方图上,从中可以得出它们的机械性能,包括弹性。通过固定频率的横向和纵向激光扫描,基于样本弹性的对比图像可以根据光子水平信号可靠地重建。
    我们证明了在长工作距离内基于QPMS的琼脂体模弹性对比成像的可靠性,低强度环境。该技术具有用于真实生物组织的深度图像的潜力,并为弹性成像研究和应用提供了新的方法。
    UNASSIGNED: Tissues\' biomechanical properties, such as elasticity, are related to tissue health. Optical coherence elastography produces images of tissues based on their elasticity, but its performance is constrained by the laser power used, working distance, and excitation methods.
    UNASSIGNED: We develop a new method to reconstruct the elasticity contrast image over a long working distance, with only low-intensity illumination, and by non-contact acoustic wave excitation.
    UNASSIGNED: We combine single-photon vibrometry and quantum parametric mode sorting (QPMS) to measure the oscillating backscattered signals at a single-photon level and derive the phantoms\' relative elasticity.
    UNASSIGNED: We test our system on tissue-mimicking phantoms consisting of contrast sections with different concentrations and thus stiffness. Our results show that as the driving acoustic frequency is swept, the phantoms\' vibrational responses are mapped onto the photon-counting histograms from which their mechanical properties-including elasticity-can be derived. Through lateral and longitudinal laser scanning at a fixed frequency, a contrast image based on samples\' elasticity can be reliably reconstructed upon photon level signals.
    UNASSIGNED: We demonstrated the reliability of QPMS-based elasticity contrast imaging of agar phantoms in a long working distance, low-intensity environment. This technique has the potential for in-depth images of real biological tissue and provides a new approach to elastography research and applications.
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  • 文章类型: Journal Article
    野生鸟类排斥在农业中至关重要,因为它有助于避免农业粮食损失并减轻禽流感的风险。野生鸟类在家禽养殖场传播禽流感,从而造成巨大的经济损失。在这项研究中,我们开发了一种自动驱鸟系统,该系统基于基于深度学习的野鸟检测,并与激光旋转机构集成。当一只野鸟出现在农场时,所提出的系统在其检测单元捕获的图像中检测到鸟的位置,然后使用激光束击退鸟。该系统的野鸟检测模型进行了优化,用于检测小像素目标,并使用在不同农场拍摄的野鸟图像通过深度学习方法进行训练。在云林的一个户外养鸭场,使用拟议的系统进行了各种野鸟排斥实验,台湾。我们的实验数据的统计测试结果表明,所提出的自动野生鸟类驱除系统有效地减少了农场中野生鸟类的数量。实验结果表明,开发的系统有效地驱除了野生鸟类,每天40.3%的高排斥率。
    Wild bird repulsion is critical in agriculture because it helps avoid agricultural food losses and mitigates the risk of avian influenza. Wild birds transmit avian influenza in poultry farms and thus cause large economic losses. In this study, we developed an automatic wild bird repellent system that is based on deep-learning-based wild bird detection and integrated with a laser rotation mechanism. When a wild bird appears at a farm, the proposed system detects the bird\'s position in an image captured by its detection unit and then uses a laser beam to repel the bird. The wild bird detection model of the proposed system was optimized for detecting small pixel targets, and trained through a deep learning method by using wild bird images captured at different farms. Various wild bird repulsion experiments were conducted using the proposed system at an outdoor duck farm in Yunlin, Taiwan. The statistical test results of our experimental data indicated that the proposed automatic wild bird repellent system effectively reduced the number of wild birds in the farm. The experimental results indicated that the developed system effectively repelled wild birds, with a high repulsion rate of 40.3% each day.
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  • 文章类型: Journal Article
    目的:通过在单一机构的系统随访,评估良性前列腺增生(BPH)患者的大型前瞻性队列中钬激光前列腺摘除术(HoLEP)的有效性和安全性。
    方法:分析了2008年8月至2022年6月间的临床结果。患者随访2周,术后3个月和6个月。
    结果:共有3,000名患者(平均年龄,69.6±7.7年)接受HoLEP。基线国际前列腺症状总评分(IPSS)为19.3±7.7,最大流速(Qmax)为9.4±4.8mL/s。平均总前列腺体积为67.7±3.4mL。总手术时间为60.7±31.5分钟,导管插入时间为1.0天(范围,1.0-1.0天)。术后6个月,总IPSS降至6.6±5.8,Qmax升至22.2±11.3mL/s。术后6个月的并发症包括压力性尿失禁(SUI)36例(1.9%),急迫性尿失禁(UUI)25(1.3%),膀胱颈挛缩症(BNC)需要经尿道切开(TUI)16(0.5%),尿道狭窄29例(1.0%)。11例前列腺窝结石患者(0.4%)需要清除结石。61例患者(2.0%)需要二次手术(经尿道电凝,16[0.5%];BNC的TUI,16[0.5%];前列腺窝结石取石,11[0.4%];尿道狭窄的内镜下尿道内切开术,18[0.6%])。
    结论:BPH患者HoLEP术后中期随访结果显示疗效好,并发症发生率低。与以前的报告不同,HoLEP后SUI和UUI的发生率较低,但前列腺窝发生了从头结石。
    OBJECTIVE: To evaluate the efficacy and safety of holmium laser enucleation of the prostate (HoLEP) in a large prospective cohort of patients with benign prostatic hyperplasia (BPH) through systematic follow-up at a single institution.
    METHODS: Clinical outcomes were analyzed between August 2008 and June 2022. Patients were followed-up at 2 weeks, 3 months and 6 months postoperatively.
    RESULTS: A total of 3,000 patients (mean age, 69.6±7.7 years) underwent HoLEP. Baseline total International Prostate Symptom Score (IPSS) was 19.3±7.7 and maximum flow rate (Qmax) was 9.4±4.8 mL/s. Mean total prostate volume was 67.7±3.4 mL. Total operation time was 60.7±31.5 minutes, and catheterization time was 1.0 days (range, 1.0-1.0 days). At 6 months postoperatively, the total IPSS decreased to 6.6±5.8 and Qmax increased to 22.2±11.3 mL/s. Complications at 6 months postoperatively included stress urinary incontinence (SUI) in 36 patients (1.9%), urgency urinary incontinence (UUI) in 25 (1.3%), bladder neck contracture (BNC) requiring transurethral incision (TUI) in 16 (0.5%), and urethral stricture in 29 (1.0%). Eleven patients (0.4%) with prostatic fossa stones required stone removal. Sixty-one patients (2.0%) required secondary surgery (transurethral coagulation, 16 [0.5%]; TUI for BNC, 16 [0.5%]; stone removal for prostatic fossa stones, 11 [0.4%]; and endoscopic internal urethrotomy for urethral stricture, 18 [0.6%]).
    CONCLUSIONS: Mid-term follow-up results after HoLEP in BPH patients showed excellent efficacy and low complication rates. Unlike previous reports, the incidence of SUI and UUI after HoLEP was low, but the occurrence of de novo stone formation in prostatic fossa was notable.
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  • 文章类型: Case Reports
    这个病例报告描述了一个40多岁的男人,有慢性吸烟史,出现发音障碍的人.他接受了显微喉镜检查和活检,发现右声带前可疑病变。由于固体病变充当球形阀进入声门,因此面罩通气在诱导全身麻醉时很困难。此肿块被激光切除并送去组织病理学检查。这证明了血肿,可能是创伤性的,具有一些息肉状特征,与Reinke的晚期水肿一致。莱因克的水肿是一种良性疾病,慢性炎症会导致声带内的液体积聚。长期的炎症导致声带固有层紊乱,引起液体积聚,从而导致声带水肿。这个过程随后可能导致息肉形成,并可能导致沙哑的声音。此病例报告描述了这种良性疾病的潜在气道后遗症。
    This case report describes a man in his mid 40s, with a history of chronic smoking, who presented with dysphonia. He underwent microlaryngoscopy and biopsy for a suspicious lesion on the anterior right vocal cord. Mask ventilation proved difficult on induction of general anaesthesia due to a solid lesion acting as a ball valve into the glottis. This mass was LASER debulked and sent for histopathology. This demonstrated a haematoma, likely traumatic in origin, with some polypoidal features, consistent with advanced Reinke\'s oedema. Reinke\'s oedema is a benign condition where chronic inflammation causes fluid accumulation within the vocal cords. Long-standing inflammation leads to disarrangement of the vocal cord lamina propria, causing fluid accumulation and thereby resulting oedema of the vocal cords. This process can subsequently lead to polyp formation and can cause gravelly voice. This case report describes the potential airway sequelae of this benign condition.
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  • 文章类型: Journal Article
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    文章类型: Journal Article
    目的-比较颜色的变化,用两种不同的漂白溶液(化学和激光活化)漂白的釉质的表面粗糙度和形态,在酸蚀刻之前或不在酸蚀刻之前。根据漂白技术,准备了30颗牛齿,并随意分配给2组(n=15)。每组细分为3个亚组(n=5),与37%磷酸的酸蚀刻一致。对漂白前后的所有样品进行两次原子力显微镜和VITA简易阴影分光光度计。方差分析,配对样本t检验,统计学分析采用独立样本t检验。至于颜色的变化,用化学方法漂白的群体,三个亚组之间的差异有统计学意义。这也适用于用激光方法漂白的基团。当比较化学漂白亚组和激光漂白亚组的结果时,差异不显著。粗糙度结果显示,某些亚组之间存在显着差异,而其他亚组之间则不存在显着差异。然而,化学组和激光组之间的差异有统计学意义,激光技术的表面粗糙度比化学技术小。漂白之前的酸蚀刻在化学和激光辅助漂白中均产生更好的颜色变化。在化学漂白中,当使用酸蚀刻时,表面粗糙度较高。对于激光漂白技术也是如此。总的来说,激光辅助漂白比化学漂白产生更小的表面粗糙度。
    Aims - to compare the color changes, the surface roughness and morphology of the enamel bleached with two different bleaching solutions (chemical and laser activated), preceded or not with acid etching. Thirty teeth of bovine prepared and haphazardly assigned to 2 groups (n=15) depending on bleaching technique. Each group subdivided to 3 subgroup (n=5) consistent with acid etching by 37% phosphoric acid. Atomic force microscopy and VITA easy shade spectrophotometer were performed twice for all the specimens before and after bleaching. ANOVA, the Paired sample t-test, and the independent sample t-test used for statistical analysis. As for the color changes, the groups that were bleached by the chemical method, the difference among the three subgroups was statistically significant. This also applies to the groups bleached with the laser method. When comparing the results of the chemical bleaching subgroups with the laser bleaching ones, the difference was not significant. Roughness results showed significant differences between certain subgroups and non-significant differences among others. However, the difference was statistically significant between the chemical and laser groups, laser technique resulted in less surface roughness than the chemical one. Acid etching before bleaching produced better colour change in both the chemical and laser assisted bleaching. In chemical bleaching, surface roughness was higher when acid etching was used. This was also true for laser bleaching technique. In general, laser assisted bleaching produced less surface roughness than chemical bleaching.
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