NEW SAR IMAGE INTERPRETATION METHOD OF AIRCRAFT BASED ON JOINT TIME-FREQUENCY ANALYSIS

With the continuous improvement of Synthetic Aperture Radar(SAR) resolution, interpreting the small targets like aircraft in SAR images becomes possible and turn out to be a hot spot in SAR application research. However, due to the complexity of SAR imaging mechanism, interpreting targets in SAR images is a tough problem. This paper presents a new aircraft interpretation method based on the joint time-frequency analysis and multi-dimensional contrasting of basic structures. Moreover, SAR data acquisition experiment is designed for interpreting the aircraft. Analyzing the experiment data with our method, the result shows that the proposed method largely makes use of the SAR data information. The reasonable results can provide some auxiliary support for the SAR images manual interpretation.

Up-to-date intraoperative computer assisted solutions for liver surgery

Computer assisted surgical planning allowed for a better selection of patients,evaluation of operative strategy, appropriate volumetric measurements,identification of anatomical risks, definition of tumour resection margins and choice of surgical approach in liver oncologic resections and living donor liver transplantations. Although preoperative computer surgical analysis has been widely used in daily clinical practice, intraoperative computer assisted solutions for risk analysis and navigation in liver surgery are not widely available or still under clinical evaluation. Computer science technology can efficiently assist modern surgeons during complex liver operations, mainly by providing image guidance with individualized 2 D images and 3 D models of the various anatomical and pathological structures of interest. Intraoperative computer assisted liver surgery is particularly useful in complex parenchyma-sparing hepatectomies, for intraoperative risk analysis and for the effective treatment of colorectal metastases after neoadjuvant therapy or when they are multiple. In laparoscopic liver surgery, intraoperative computer aid is definitively more important as, apart from a restricted field of view, there is also loss of the fine haptic feedback. Intraoperative computer assisted developments face challenges that prevent their application in daily clinical practice. There is a vast variety of studies regarding intraoperative computer assisted liver surgery but there are no clear objective measurements in order to compare them and select the most effective solutions. An overview of up-to-date intraoperative computer assisted solutions for liver surgery will be discussed.

Image interpretation of weak-coupling N-mer adsorbate's STM system

Up to now, there have been many indistinctive points in the image interpretation of scanning tunnelhng microscopy (STM) system, and the problems have attracted almost all STM scientists’ attention. In 1992, Kenkre proposed the new programme which describes the behaviour of the electrons moving in the STM tunnelling by the method of exciton dynamics, and the programme not only breaks through the restrictions of Tersoff-Hamann theory, but also can be applied conveniently to discussing the effects of the tip structure, adsorbate structure, substrate structure, temperature, tunneling voltage, and the degree of coherence of elec-

Study of the Retinal Imaging and Output in Premature Baby under a Computer-assisted Binocular Indirect Ophthalmoscope

Purpose:To explore a clear retinal imaging and output and enhance the development of retinopathy of prematurity (ROP) screening,which is safe and effective for ROP screening in premature infants. Methods:A computer-assisted binocular indirect ophthalmoscope imaging and output system was equipped with camera and image processing hardware and connected to computers. The process of fundus examination was videotaped (photograph) and output. Simulated eyes were utilized to debug video head and acquire stable and clear fundus images by binocular indirect ophthalmoscope for premature infants. Results:Fundus imaging output technique was sucessfully established. The common reasons of unclear imaging and corresponding solutions were summarized. This technique can capture and output stable and clear fundus images of premature infants. Conclusion: Assisted by hardware and software processing, a compute assisted binocular indirect ophthalmoscope imaging and output system was established,which can be used for screening, research, treatment and follow-up of ROP in premature babies to resolve the difficulty in obtaining clear fundus photograph.

Image interpretation: mining the visible and syntactic correlation of annotated words

Automatic web image annotation is a practical and effective way for both web image retrieval and image understanding. However, current annotation techniques make no further investigation of the statement-level syntactic correlation among the annotated words, therefore making it very difficult to render natural language interpretation for images such as "pandas eat bamboo". In this paper, we propose an approach to interpret image semantics through mining the visible and textual information hidden in images. This approach mainly consists of two parts: first the annotated words of target images are ranked according to two factors, namely the visual correlation and the pairwise co-occurrence; then the statement-level syntactic correlation among annotated words is explored and natural language interpretation for the target image is obtained. Experiments conducted on real-world web images show the effectiveness of the proposed approach.

MARKER-BASED MAPPING BETWEEN MEDICAL IMAGE AND ROBOT SPACE IN ROBOT-ASSISTED SURGERY

This paper focuses on the problems of matching a virtual and a real environments by means of hardware and software tools. The real space is represented by a patient’s bone where a set of cuts by means of robot system is to be made. The virtual space is a 3D model of the bone reconstructed from a set of CT slices. Robot system is then not only to machine bones but also to perform the fundamental step of registration between the two spaces. An external force sensor is used to adjust robot stiffness in order to perform the tactile searching necessary for the registration. A simple but reliable software algorithm is used to control the robot for matching between medical image and robot space in robot-assisted surgery. The results show the system proposed is precise enough for application, and tests been made also clarify the way to improve it.

矿物组分识别与智能解释在不同岩性之间的信息共享与迁移学习

在地球科学领域,岩石微观观测数据的采集过程繁琐且效率低下,这不仅增加了研究成本,降低了可靠性,同时也限制了数据的开源共享。此外,由于岩性的多样性和观测手段的差异,单一数据集的规模通常较小,这对于依赖大规模数据集的深度学习框架而言是一大挑战。为此,本研究探索迁移学习如何促进不同岩性间的信息共享,并通过此机制提高矿物组分识别与智能解释任务的模型性能。通过采集不同区域、岩性、矿物组分和偏光模式下的铸体薄片样本,本文深入研究了深度学习模型在不同观测对象和手段下的迁移学习机制,并聚焦于探索地质信息的深层表征。研究成果不但揭示了迁移学习在促进地质学领域信息共享与模型性能提升中的关键作用,还为自动化和智能化地质认识融合奠定了基础。实验结果显示,通过迁移学习,本文模型在智能解释任务中的准确率显著提高,从53.3%提高至98.73%,而在矿物组分识别任务中,准确率也实现了近10%的提升。这些成果证明了迁移学习在地质学领域内解决实际问题和提高模型泛化能力、性能和稳定性方面的巨大潜力。

Extravasated contrast volumetric assessment on computed tomography angiography in gastrointestinal bleeding:A useful predictor of positive angiographic findings

BACKGROUND Gastrointestinal bleeding(GIB)is a severe and potentially life-threatening condition,especially in cases of delayed treatment.Computed tomography angiography(CTA)plays a pivotal role in the early identification of upper and lower GIB and in the prompt treatment of the haemorrhage.AIM To determine whether a volumetric estimation of the extravasated contrast at CTA in GIB may be a predictor of subsequent positive angiographic findings.METHODS In this retrospective single-centre study,35 patients(22 men;median age 69 years;range 16-92 years)admitted to our institution for active GIB detected at CTA and further submitted to catheter angiography between January 2018 and February 2022 were enrolled.Twenty-three(65.7%)patients underwent endoscopy before CTA.Bleeding volumetry was evaluated in both arterial and venous phases via a semi-automated dedicated software.Bleeding rate was obtained from volume change between the two phases and standardised for unit time.Patients were divided into two groups,according to the angiographic signs and their concordance with CTA.RESULTS Upper bleeding accounted for 42.9%and lower GIB for 57.1%.Mean haemoglobin value at the admission was 7.7 g/dL.A concordance between positive CTA and direct angiographic bleeding signs was found in 19(54.3%)cases.Despite no significant differences in terms of bleeding volume in the arterial phase(0.55 mL vs 0.33 mL,P=0.35),a statistically significant volume increase in the venous phase was identified in the group of patients with positive angiography(2.06 mL vs 0.9 mL,P=0.02).In the latter patient group,a significant increase in bleeding rate was also detected(2.18 mL/min vs 0.19 mL/min,P=0.02).CONCLUSION In GIB of any origin,extravasated contrast volumetric analysis at CTA could be a predictor of positive angiography and may help in avoiding further unnecessary procedures.

ISO 11798:2023《信息与文献纸张上书写、打印和复印图像的耐久性和耐用性要求与测试方法》标准解读

ISO11798:2023规定了长期保存在图书馆、档案馆等可控环境中纸质文献的书写、打印、复印图像的耐久性和耐用性的要求与测试方法,不仅为图书馆、档案馆等单位更好地开展纸质文献保护工作提供助力,同时也为出版印刷行业提高印刷质量提供了重要参考。本文详细介绍了最新版ISO11798标准的修订背景、修订过程以及主要修订内容,希望能为相关从业人员研究新标准文本及制定相应国家标准提供帮助。

基于改进HRNet的遥感影像冬小麦语义分割方法

冬小麦在影像中呈现田块碎小且分布零散等空间特征,同时影像包含的复杂地物对冬小麦识别造成干扰,易出现识别精度低且边界分割模糊等问题。为及时准确获取大范围冬小麦空间分布信息,该研究以高分二号卫星影像作为数据源,提出一种CAHRNet(change attention high-resolution Net)语义分割模型。采用HRNet(high-resolution Net)替换ResNet作为模型的主干网络,网络的并行交互方式易获取高分辨率的特征信息;联合OCR(object-contextual representations)模块聚合上下文信息,以增强像素点与目标对象区域的关联性;3)引入坐标注意力(coordinate attention)机制,使网络模型充分利用有效的空间位置信息,以保留分割区域的边缘细节,提高对分布零散、形状多变的冬小麦田块的特征提取能力。试验结果表明,在自制的高分辨率遥感数据集上,CAHRNet模型的平均交并比(mean intersection over union,MIoU)和像素准确率(pixel accuracy, PA)分别达到81.72%和97.08%,MIoU相较U-Net、DeepLabv3+分别提高了9.09、2.44个百分点;PA相较U-Net、DeepLabv3+分别提高6.80、1.59个百分点,说明CAHRNet模型具有较高的分割识别精度,可为进一步准确获取冬小麦作物分布信息提供技术支撑。

用者为本,技之大道--评《以口译员为中心的技术可用性研究:以SmarTerp为例》

在口译学科“技术转向”的时代背景下,口译技术人性化和可持续发展的重要性日益凸显。《以口译员为中心的技术可用性研究:以SmarTerp为例》一书立足时代需求,介绍了全球首项使用可用性工程方法开发计算机辅助口译工具的案例研究,旨在反映口译领域技术变革,确保口译技术的公平可持续发展。该书通过采用人机交互的理论框架和方法论框架评估计算机辅助口译工具SmarTerp界面的可用性,弥补了当前计算机辅助口译实证研究的不足,对口译技术的研发和应用具有重要的启发意义和借鉴价值。

矩形空洞探地雷达成像曲线厚度变化规律研究

由于城市基础建设不断地翻新改造,引发城市地下空洞滋生问题。通过探地雷达扫描技术,对地下矩形空洞整个探测过程进行研究,将探测过程划分为四个阶段,研究了成像曲线厚度变化规律。对探地雷达水平运行时矩形空洞的成像曲线厚度变化规律进行分析,对不同大小下的矩形空洞点测时曲线厚度进行研究,并通过实际探测案例来解释矩形空洞成像曲线厚度变化规律,结果表明探地雷达探测矩形空洞时其成像曲线厚度为先增加后减小的对称曲线,其曲线厚度最大处在图像上为水平弧段两端,位于实际矩形空洞对角线附近;雷达点测时成像曲线厚度随矩形空洞变大而增加,在图像上表现为空洞越大线条越粗。

白术的法象药理及其临床意义

“以象释药”是中医象思维在中药学研究与应用中的极好体现。白术为“后天培土圣药”,但在《神农本草经》等本草经典中,古人常以之治疗痃癖、结肿、山岚瘴气等诸多疑难怪证。对此,按药性常论往往难以理解。但若以“法象药理”“象性合参”的角度,这些功效应用可以从白术独特的“药象”中找到答案。古代本草著作对于白术特殊药象多有详尽阐释,称之为“盘结丑怪,有兽之形”,以及“桴蓟”“多刺有风象”等。笔者结合传统本草和现代药学研究,将白术的药象特点概括为:叶裂羽刺,团根瘤皱,肉白辛香。而这些药象均与其“逐风水结肿”“痃癖气块”“主大风在身面”等特殊药效密切相关。正如徐灵胎所言:“因形以求理,则其效可知矣。”由此认识白术的“象-效”相关性,可帮助我们理解古人的药学智慧,弘扬传统本草理论的现代应用价值。

视频侦查技术关键及其发展展望

视频侦查技术的核心是通过视频图像的提取、查看、分析和研判来获取侦查线索、固定涉案证据。多年来经过在实战应用中不断地发展创新,视频侦查技术形成了自己独特的关键技术体系:视频信息分析解读技术是侦查应用和证据固定的基础和核心;视频证据固定保全技术的规范是审判中心主义的客观要求,可以获取视频侦查记录报告、视频检验鉴定报告或视频数据关联报告;低质量视频图像的增强恢复技术专业性强,应用范围窄,技术成熟度高,然而它不断面临新的挑战。目前,视频数据的智能应用在大数据背景下变得越来越重要,仍需进一步突破视频自动识别技术的应用范畴,建立完善多层次的视频数据综合应用体系,打造适应不同业务需要的视频数据实战应用模型。

面向电力生产精细化风险解译的高度相似防护工具智能检测技术研究

电力生产通常面临高低电压、强弱电流等复杂工作环境转换,不同作业场景有严格的防护工具使用标准,因此,研究生产作业过程防护工具的精细辨识对保障人员安全及电网安全意义重大。已有研究可实现安全帽、工作服等基础着装类检测,而实际生产中存在大量形态高度相似的实体防护工具,如绝缘手套与线手套、绝缘杆与验电杆等。为此,该文提出一种基于深度代表性度量学习的相似防护工具智能检测方法。将目标类别特征学习转换为以差异化表达不同目标特征距离为目的的嵌入式空间特征学习,得到表征不同目标的深度代表性特征向量,通过计算未知目标与代表性特征向量的距离进行类别判断,最后以现场图像进行试验验证。试验结果表明:所提方法实现了对形态相似防护工具的特征差异表达和精准辨识,相比于常见目标检测模型具有更优越的辨识性能,从而提高电力生产安全风险辨识的精细化水平。

仿真滤线栅及图像增强后处理算法用于改善儿童低剂量X线片图像质量

目的 观察以仿真滤线栅(SG)和图像增强(SE)改善儿童低剂量X线片图像质量的价值。方法 回顾性分析344例接受410次床旁X线检查的重症监护病房患儿资料,包括290幅胸部平片、51幅腹部平片及69幅胸腹联合平片;分别以SG和SE对图像进行后处理,评估后处理图像质量。结果 410幅SG后处理图像中,2分250幅、1分147幅、0分13幅;SG可显著改善年龄≥1岁和体质量≥10 kg患儿图像质量(P均<0.05),且显示骨骼、气管、外周血管、异物、腰大肌和肠道气体效果较好(P均<0.05)。410幅SE后处理图像中,2分250幅、1分58幅、0分102幅;SE可显著改善年龄≥0.5岁和体质量>4 kg患儿图像质量(P均<0.05),且显示骨骼、气管、大血管、外周血管、心脏后血管和异物效果较好(P均<0.05)。结论 SG可显著改善低剂量X线片显示年龄≥1岁和体质量≥10 kg儿童骨骼、气管、外周血管、异物、腰大肌和肠道气体的质量,而SE则可改善显示年龄≥0.5岁和体质量>4 kg儿童骨骼、气管、大血管、外周血管、心脏后血管和异物的质量。

MSCT后处理技术诊断耳硬化症

目的观察多层螺旋CT(MSCT)后处理技术用于诊断耳硬化症的价值。方法回顾性收集47例(92耳)耳硬化症及65例(79耳)非耳硬化症听力障碍患者的临床资料及轴位平扫MSCT,对MSCT原始图像行后处理,包括镫骨、耳蜗多平面重组(MPR)及听骨链曲面重组(CPR),比较MSCT原始图像及其联合后处理技术诊断耳硬化症的效能。结果根据MSCT原始图像诊断66耳、联合后处理技术诊断89耳耳硬化症,二者敏感度分别为71.74%和96.74%,诊断准确率分别为81.29%和96.49%,后者均高于前者(P均<0.05);其特异度(92.41%vs.96.20%)差异无统计学意义(P>0.05)。结论联合后处理技术有助于提高MSCT诊断耳硬化症的敏感度和准确率。

基于多期相CT图像的深度学习ResNet18和ResNet50模型诊断肾结核的效能比较

目的:探讨基于CT图像构建深度学习模型对肾结核进行鉴别诊断的可行性。方法:回顾性分析2018年9月至2020年8月经解放军总医院第八医学中心收治,并经组织病理学或临床确诊的肾结核、肾肿瘤、肾盂肾炎、正常肾脏、肾囊肿、肾积水患者。共纳入200例患者共400个肾脏的CT图像数据。将400个肾脏CT图像分为结核组(114个)和非结核组(286个),并且按8∶2的比例分为训练集(肾结核:85个;非肾结核:235个)和测试集(肾结核:29个;非肾结核:51个)。基于训练集通过ResNet18和ResNet50网络分别构建肾脏平扫期、皮髓质期、实质期和排泄期的深度学习模型;基于测试集评估所构建模型对肾结核的诊断效能,计算受试者工作特征曲线(ROC)曲线下面积(AUC)、敏感度、特异度、准确率和F1分数。结果:训练集中,结核组平均年龄为(41.27±11.75)岁,明显低于非结核组[(54.05±13.97)岁];测试集中,结核组平均年龄为(44.06±11.95)岁,明显低于非结核组[(56.12±10.73)岁],差异均有统计学意义(t值分别为5.753、3.444,P值均<0.05)。训练集中,结核组男性占66.7%(40/60),女性占33.3%(20/60);非结核组男性占60.9%(78/128),女性占39.1%(50/128);两组差异无统计学意义(χ^(2)=0.009,P=0.924)。测试集中,结核组男性占64.3%(18/28),女性占35.7%(10/28);非结核组男性占58.7%(27/46),女性占41.3%(19/46);两组差异无统计学意义(χ^(2)=0.018,P=0.894)。ResNet18模型肾脏各期相的AUC、敏感度、特异度、准确率和F1分数均高于ResNet50模型。ResNet18模型中以皮髓质期为最佳,AUC、敏感度、特异度、准确率和F1分数分别为0.925、93.1%、86.3%、88.7%和0.857;ResNet50模型皮髓质期AUC、敏感度、特异度、准确率和F1分数分别为0.858、72.4%、84.3%、80.0%和0.724。结论:基于多期相CT图像的ResNet18模型诊断肾结核的效能优于ResNet50模型,ResNet18模型中以皮髓质期诊断效能最佳,有较高的临床应用价值。

乳腺X线及MRI特征联合临床病理预测乳腺导管原位癌伴微浸润

目的探讨基于临床病理、乳腺X线(mammography,MG)和MRI特征预测乳腺导管原位癌伴微浸润(ductal carcinoma in situ with microinvasion,DCISM)的价值。材料与方法回顾性收集宁夏医科大学总医院2019年6月至2022年6月最终经手术病理证实为纯导管原位癌(ductal carcinoma in situ,DCIS)和DCISM的首诊女性患者的病例资料为训练组,评估术前患者的临床病理、MG和MRI特征。采用单、多因素logistic回归分析明确DCISM的独立危险因素,并建立联合模型。通过受试者工作特征(receiver operating characteristic,ROC)曲线下面积(area under the curve,AUC)及校准图评估模型的诊断效能,应用决策曲线分析(decision curve analysis,DCA)观察联合模型的临床实用性。前瞻性收集2022年7月至2023年7月符合纳入、排除标准的患者作为验证组进行验证。应用沙普利加和解释(Shapley Additive exPlanation,SHAP)分析联合模型中病灶最长径、核级别、坏死、Ki-67指数、P63状态、钙化状态和最小ADC值(minimum value of apparent diffusion coefficient,ADCmin)预测DCISM的价值。收集535例患者共550个病灶(15例患者为同时性双乳癌),患者年龄23~81岁,中位年龄50岁。训练组(n=382)中102个病灶(27%)和验证组(n=168)中52个病灶(31%)被诊断为DCISM。结果多因素logistic回归结果显示,病灶最长径、核级别、坏死、Ki-67指数、P63状态、钙化状态和ADCmin是DCISM的独立危险因素。基于上述参数构建临床病理及联合模型,在训练组和验证组中均表现出较高的预测效能(AUC:0.937、0.899)。根据SHAP分析,病灶最长径、Ki-67指数和ADCmin在联合模型中对预测DCISM起主要贡献,而钙化状态、核级别、P63状态和坏死是补充因素。结论联合临床病理及术前MG和MRI特征的预测模型可有效从纯DCIS区分出DCISM,从而提升临床决策和治疗规划的准确性。