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Quasi-holography computational model for urban computing

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Visual Informatics 2019年第2期3卷 81-86页

作者： baoquan chen Qiong Zeng Zhanglin cheng Peking University China Shandong University China Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesChina

Vast amounts of data are produced with the development of smart cities and urban computing technologies.The data is often captured from multiple sensors,with heterogeneous structures and highly decentralized connections.Integrated data representation and smart computational models are required for more complex tasks in urban computing.We dwell deeply on two fundamental questions—can we provide an integrated data representation for the whole cyber–physical–social system?And,can we provide an integrated framework to choose the appropriate data for understanding a specific urban event?A holography data representation and the quasi-holography computational model have been proposed to address these problems.We describe case studies using the quasi-holography computational model,and discuss further problems to solve regarding our model.

关键词： Holography model Urban data representation

Group optimization for multi-attribute visual embedding

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Visual Informatics 2018年第3期2卷 181-189页

作者： Qiong Zeng Wenzheng chen Zhuo Han Mingyi Shi Yanir Kleiman Daniel Cohen-Or baoquan chen Yangyan Li School of Computer Science&Technology Shandong UniversityQingdaoChina Department of Computer Science University of TorontoTorontoCanada Viterbi School of Engineering University of Southern CaliforniaCAUnited States DNEG Visual Effects LondonUnited Kingdom School of Computer Science Tel Aviv UniversityTel AvivIsrael

Understanding semantic similarity among images is the core of a wide range of computer graphics and computer vision applications.However,the visual context of images is often ambiguous as images that can be perceived with emphasis on different attributes.In this paper,we present a method for learning the semantic visual similarity among images,inferring their latent attributes and embedding them into multi-spaces corresponding to each latent attribute.We consider the multi-embedding problem as an optimization function that evaluates the embedded distances with respect to qualitative crowdsourced clusterings.The key idea of our approach is to collect and embed qualitative pairwise tuples that share the same attributes in clusters.To ensure similarity attribute sharing among multiple measures,image classification clusters are presented to,and solved by users.The collected image clusters are then converted into groups of tuples,which are fed into our group optimization algorithm that jointly infers the attribute similarity and multi-attribute embedding.Our multi-attribute embedding allows retrieving similar objects in different attribute spaces.Experimental results show that our approach outperforms state-of-the-art multi-embedding approaches on various datasets,and demonstrate the usage of the multi-attribute embedding in image retrieval application.

关键词： Embedding Semantic similarity Visual retrieval

基于C-TIRADS评分的列线图预测cN0甲状腺乳头状癌颈中央区淋巴结转移

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中国超声医学杂志 2024年第2期40卷 141-144页

作者：徐锦洋陈宝泉吴珠娥卢发辉福建医科大学附属漳州市医院超声医学科

目的基于中国甲状腺影像报告和数据系统(C-TIRADS)评分构建列线图以预测临床颈部淋巴结转移阴性(cN0)甲状腺乳头状癌(PTC)颈中央区淋巴结转移(CLNM)。方法选取确诊cN0 PTC的859个癌灶，依据手术时间顺序，按7∶3比例分为建模队列、验... 详细信息

目的基于中国甲状腺影像报告和数据系统(C-TIRADS)评分构建列线图以预测临床颈部淋巴结转移阴性(cN0)甲状腺乳头状癌(PTC)颈中央区淋巴结转移(CLNM)。方法选取确诊cN0 PTC的859个癌灶，依据手术时间顺序，按7∶3比例分为建模队列、验证队列。采用单因素及多因素Logistic回归分析筛选独立危险因素，基于筛选结果构建预测CLNM的列线图并验证其临床应用价值。结果建模队列中，性别、病灶最大径、C-TIRADS评分是独立危险因素。建模及验证队列的受试者工作曲线下面积(AUC)分别为0.834、0.817,表明其具有良好的区分度。Bootstrap法(B=1 000次)绘制的校准曲线结果说明其具有较好的校准度(Hosmer-Lemeshow拟合优度检验，P=0.16)。决策曲线分析(DCA)显示该列线图的风险阈值为0.2～0.9,表明具有良好的临床应用价值。结论基于C-TIRADS评分构建的列线图预测模型可以在术前较准确地预测CLNM。

关键词：中国甲状腺影像报告和数据系统评分临床颈部淋巴结转移阴性甲状腺乳头状癌颈中央区淋巴结转移

肾动脉阻力指数在重症患者腹高压诊断中的应用价值

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中华急诊医学杂志 2024年第3期33卷 360-364页

作者：陈宝泉陈明徐锦洋吕国荣杨燕芬杨舒萍福建医科大学附属漳州市医院超声医学科漳州363000 泉州医学高等专科学校母婴健康服务应用技术协同创新中心泉州362000

目的探讨肾动脉阻力指数(resistance index,RI)在重症患者腹高压(intra-abdominal pressure,IAH)诊断中的应用价值。方法回顾性分析2022年2月至2022年6月入住漳州市医院重症监护室具有IAH危险因素的89名患者,根据经膀胱测得的腹内压(IAP... 详细信息

目的探讨肾动脉阻力指数(resistance index,RI)在重症患者腹高压(intra-abdominal pressure,IAH)诊断中的应用价值。方法回顾性分析2022年2月至2022年6月入住漳州市医院重症监护室具有IAH危险因素的89名患者,根据经膀胱测得的腹内压(IAP)分为IAH组(IAP≥12 mmHg)和非IAH组(IAP<12 mmHg),应用彩色多普勒超声测量右肾主动脉、段动脉、叶间动脉的RI值,分析IAH组与非IAH组患者各测量参数的差异性及其与IAP的相关性。对不同指标预测IAH的诊断效能,采用ROC曲线分析进行评估,并同时行多因素Logistic回归分析寻找独立危险预测因子。结果总共有89名患者纳入研究,44例IAP正常,45例诊断为IAH。IAH组与非IAH组相比,右肾主动脉、段动脉、叶间动脉RI均差异具有统计学意义(均P<0.01),其中以叶间动脉RI≥0.698为诊断截值时诊断效能最高,曲线下面积0.914,敏感度82.2%,特异度97.7%,约登指数0.799;Spearman相关性分析显示右肾叶间动脉RI与IAP具有较强的相关性(r=0.741,P<0.01)。多因素Logistic回归分析结果显示右肾叶间动脉RI值(OR=24.472,95%CI:5.122~116.919,P<0.01)是IAH的独立危险预测因子。结论右肾叶间动脉RI值诊断IAH有较好的诊断效能,肾动脉超声可以作为诊断和随访IAH的一种替代的、非侵入性的技术。

关键词：超声肾动脉阻力指数重症患者腹高压

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3D visual processing and reconstruction

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Virtual Reality & Intelligent Hardware 2020年第3期2卷 I0001-I0002页

作者： baoquan chen Peking University Beijing 100871China

3D sensing represents the main channel through which humans,or robotics agents,understand and interact with each other and with the real world.As such,many 3D acquisition technologies and devices have been developed and applied in emerging applications,such as autonomous systems,augmented reality and digital production.A typical 3D visual system takes RGB and/or range images of an object or scene and generates 3D geometry.

关键词： visual autonomous processing

100 GHz silicon–organic hybrid modulator

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Light(Science & Applications) 2014年第1期3卷 196-199页

作者： Luca Alloatti Robert Palmer Sebastian Diebold Kai Philipp Pahl baoquan chen Raluca Dinu Maryse Fournier Jean-Marc Fedeli Thomas Zwick Wolfgang Freude Christian Koos Juerg Leuthold Institutes IPQ and IMT Karlsruhe Institute of Technology(KIT)76131 KarlsruheGermany Institute IHE Karlsruhe Institute of Technology(KIT)76131 KarlsruheGermany GigOptix Inc. BothellWAUSA CEA Leti38054 GrenobleFrance Institute of Photonic Systems Swiss Federal Institute of

Electro-optic modulation at frequencies of 100 GHz and beyond is important for photonic-electronic signal processing at the highest speeds.To date,however,only a small number of devices exist that can operate up to this frequency.In this study,we demonstrate that this frequency range can be addressed by nanophotonic,silicon-based modulators.We exploit the ultrafast Pockels effect by using the silicon–organic hybrid(SOH)platform,which combines highly nonlinear organic molecules with silicon waveguides.Until now,the bandwidth of these devices was limited by the losses of the radiofrequency(RF)signal and the RC(resistor-capacitor)time constant of the silicon structure.The RF losses are overcome by using a device as short as 500 μm,and the RC time constant is decreased by using a highly conductive electron accumulation layer and an improved gate insulator.Using this method,we demonstrate for the first time an integrated silicon modulator with a 3dB bandwidth at an operating frequency beyond 100 GHz.Our results clearly indicate that the RC time constant is not a fundamental speed limitation of SOH devices at these frequencies.Our device has a voltage–length product of only V_(π)L=11 V mm,which compares favorably with the best silicon-photonic modulators available today.Using cladding materials with stronger nonlinearities,the voltage–length product is expected to improve by more than an order of magnitude.

关键词： 100GHz high-speed silicon modulator nanophotonics silicon–organic hybrid

孕早期应用胎盘三维能量多普勒超声预测治疗性早产的价值

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中国医药指南 2024年第19期22卷 43-46页

作者：陈碧容黄淑铉陈宝泉陈顺姬杨舒萍福建医科大学附属漳州市医院超声科漳州363000

目的探索三维能量多普勒超声(3D-PD)指标评估胎盘血流灌注以预测治疗性早产,指导临床早发现、早监测、早干预,实现孕产期全程个性化管理。方法纳入2022年1—11月在福建医科大学附属漳州市医院规律产检的孕早期单胎孕妇348例,根据分娩... 详细信息

目的探索三维能量多普勒超声(3D-PD)指标评估胎盘血流灌注以预测治疗性早产,指导临床早发现、早监测、早干预,实现孕产期全程个性化管理。方法纳入2022年1—11月在福建医科大学附属漳州市医院规律产检的孕早期单胎孕妇348例,根据分娩孕周,分为早产组(31例)和足月组(317例),分析两组3D-PD测得的胎盘血管化指数(VI)、流量指数(FI)、血管化流量指数(VFI)指标的差异。采用受试者工作特征(ROC)曲线分析不同指标预测治疗性早产的诊断效能,并采用多因素Logistic回归分析影响因素。结果早产组胎盘VI、FI、VFI均低于足月组(P <0.05)。VI、VFI预测治疗性早产的曲线下面积(AUC)相近且均大于FI,VI、VFI的灵敏度分别为70.97%、70.97%,特异度分别为89.91%、83.91%,其中VI、FI、VFI截断值分别为9.094、27.199、3.085。多因素Logistic回归分析显示,VI是导致治疗性早产的独立影响因素(P <0.001)。结论孕早期胎盘3D-PD指标能够为早期预测治疗性早产提供量化指标,指导临床早期对高危孕妇进行干预,降低早产的发生率、病死率,改善围生期结局。

关键词：孕早期治疗性早产三维能量多普勒超声胎盘血流灌注围生期妊娠结局

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Synthesis and Antitumor Activities of 1,3,4-Thiadiazole Derivatives Possessing Benzisoselenazolone Scaffold

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Chemical Research in Chinese Universities 2014年第5期30卷 764-769页

作者： ZHAO Jie XUAN Lina ZHAO Haichuan chenG Ji FU Xiaoyun LI Sha JING Fen LIU Yuming chen baoquan School of Chemistry and Chemical Engineering Tianjin University of Technology Tianjin 300384 P. R. China

A series of novel 1,3,4-thiadiazole derivatives possessing benzisoselenazolone scaffold were designed and synthesized, and their antitumor activities against human cervix adenocarcinoma（HeLa）, human liver cancer cell（SMMC-7721）, human breast cancer cell（MCF-7） and human lung cancer cell（A549） lines were evaluated by CCK-8 assay, The bioassay results demonstrate that most of the tested compounds showed potent antiproliferative effects against various cell lines. Furthermore, compounds 7c, 7e, 7h, 7i and 7k showed significant antiproliferative activities against SMMC-7721 cells, with IC5o values of 2.38, 2.67, 1.35, 2.75 and 2.48 μmol/L, respectively. Com- pounds 7a, 7e, 7j and 71 exhibited highly effective antitumor activities against MCF-7 cells, with IC50 values of 2.89, 2.95, 1.12 and 2.75 μmol/L, respectively. Compound 7j was found to be the most potent compound against A549 cells, with an IC50 value of 1.25 μmol/L. The pharmacological results suggest that the substituents of benzylthio-moiety at position 2 on 1,3,4-thiadiazole are vital for modulating antitumor activities against various cancer cell lines.

关键词： 1,3,4-Thiadiazole derivative Benzisoselenazolone Antitumor activity

电流密度对Ni-W-Ti_(3)C_(2)T_(x)复合镀层耐腐蚀性能的影响

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稀有金属 2022年第10期46卷 1298-1305页

作者：肖绮陈蔚清陈杨连邹金明陈宝泉张雪辉江西理工大学材料冶金化学学部江西赣州341000

利用直流电沉积法在45^(#)钢表面成功制备出Ni-W-Ti_(3)C_(2)T_(x)复合镀层,采用场发射扫描电子显微镜(FESEM)、X射线衍射仪(XRD)、维氏硬度计及电化学工作站等研究了电流密度对Ni-W-Ti_(3)C_(2)T_(x)复合镀层显微组织、显微硬度与耐腐... 详细信息

利用直流电沉积法在45^(#)钢表面成功制备出Ni-W-Ti_(3)C_(2)T_(x)复合镀层,采用场发射扫描电子显微镜(FESEM)、X射线衍射仪(XRD)、维氏硬度计及电化学工作站等研究了电流密度对Ni-W-Ti_(3)C_(2)T_(x)复合镀层显微组织、显微硬度与耐腐蚀性能的影响。结果表明:电流密度对复合镀层的表面形貌和性能有极大的影响。在电流密度为3 A·dm^(-2)时,镀层表面较为均匀但镀层厚度很小,此时由于Ti_(3)C_(2)T_(x)的沉积效率很低导致硬度值最低(HV_(0.1)492.85)。在电流密度为5 A·dm^(-2)时,镀层表面均匀且致密,此时镀层的硬度值最高(HV_(0.1)631.36),自腐蚀电位最大(-633 mV),自腐蚀电流密度最小(4.550×10^(-3)mA·cm^(-2)),此时镀层的耐腐蚀性能最优。当电流密度过大(9 A·dm^(-2))时,镀层表面会出现裂纹孔洞等缺陷,从而使得镀层的耐腐蚀性能降低。这表明,电流密度适当的提高能够有效提高基质金属沉积效率和Ti_(3)C_(2)T_(x)沉积效率,并且能改善镀层表面质量,这对复合镀层的硬度和耐腐蚀性能有决定性的影响。

关键词：复合镀层电流密度显微硬度腐蚀性能

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