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Full-parameter omnidirectional transformation optical devices

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National Science Review 2024年第3期11卷 92-99页

作者： Yuan Gao Yu Luo Jingjing Zhang zhengjie Huang bin zheng Hongsheng Chen Dexin Ye Interdisciplinary Center for Quantum Information State Key Laboratory of Extreme Photonics and InstrumentationZJU-Hangzhou Global Scientific and Technological Innovation CenterZhejiang University School of Electrical and Electronic Engineering Nanyang Technological University CNRS-InternationalNTU-Thales Research Alliance Nanyang Technological University Institute of Electromagnetic Space Southeast University State Key Laboratory of Millimeter Waves Southeast University International Joint Innovation Center The Electromagnetics Academy at Zhejiang University Zhejiang University Key Laboratory of Advanced Micro/Nano Electronic Devices&Smart Systems of Zhejiang Jinhua Institute of Zhejiang UniversityZhejiang University Shaoxing Institute of Zhejiang University Zhejiang University

Transformation optics(TO) provides an unprecedented technique to control electromagnetic(EM) waves by engineering the constitutive parameters of the surrounding medium through a proper spatial transformation. In general, ideal transformation optical devices require simultaneous electric and magnetic responses along all three dimensions. To ease the practical implementation, previous studies usually made use of reduced parameters or other simplified approaches, which inevitably introduce extra reflection or unwanted phase shift. Up to today, experimental realizations of full-parameter transformation optical devices in free space are still quite limited. Here, a general design strategy is proposed to solve this *** a specific example, a full-parameter spatial-compression TO medium with constitutive parameters taking the diagonal form diag(a, a, 1/a) for the TM wave incidence was designed and realized experimentally. Such spatial-compression TO media were then applied to the implementation of an ideal omnidirectional invisibility cloak capable of concealing a large-scale object over a wide range of illumination angles. Both the simulation and experiment confirm that the cloak allows for nearly unity transmission of EM waves in the forward direction without introducing extra scattering or phase shift. This work constitutes an important stepping stone for future practical implementation of arbitrary full-parameter omnidirectional transformation optical devices.

关键词： transformation optical devices omnidirectional impedance matching full-parameter invisibility cloak

Machine learning prediction model for gray-level co-occurrence matrix features of synchronous liver metastasis in colorectal cancer

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World Journal of Gastrointestinal Surgery 2024年第6期16卷 1571-1581页

作者： Kai-Feng Yang Sheng-Jie Li Jun Xu Yong-bin zheng Department of Gastrointestinal Surgery Renmin Hospital of Wuhan UniversityWuhan 430030Hubei ProvinceChina Department of Gastrointestinal Surgery The First College of Clinical Medical ScienceChina Three Gorges UniversityYichang Central People’s HospitalYichang 443008Hubei ProvinceChina

BACKGROUND Synchronous liver metastasis(SLM)is a significant contributor to morbidity in colorectal cancer(CRC).There are no effective predictive device integration algorithms to predict adverse SLM events during the diagnosis of *** To explore the risk factors for SLM in CRC and construct a visual prediction model based on gray-level co-occurrence matrix(GLCM)features collected from magnetic resonance imaging(MRI).METHODS Our study retrospectively enrolled 392 patients with CRC from Yichang Central People’s Hospital from January 2015 to May *** were randomly divided into a training and validation group(3:7).The clinical parameters and GLCM features extracted from MRI were included as candidate *** prediction model was constructed using a generalized linear regression model,random forest model(RFM),and artificial neural network *** operating characteristic curves and decision curves were used to evaluate the prediction *** Among the 392 patients,48 had SLM(12.24%).We obtained fourteen GLCM imaging data for variable screening of SLM prediction *** difference,mean sum,sum entropy,sum variance,sum of squares,energy,and difference variance were listed as candidate variables,and the prediction efficiency(area under the curve)of the subsequent RFM in the training set and internal validation set was 0.917[95%confidence interval(95%CI):0.866-0.968]and 0.09(95%CI:0.858-0.960),*** A predictive model combining GLCM image features with machine learning can predict SLM in *** model can assist clinicians in making timely and personalized clinical decisions.

关键词： Colorectal cancer Synchronous liver metastasis Gray-level co-occurrence matrix Machine learning algorithm Prediction model

Bacterial nanocellulose assembly into super-strong and humidity-responsive macrofibers

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Journal of Bioresources and Bioproducts 2024年第3期9卷 369-378页

作者： Yadong Zhao zheng Yang Rusen Zhou bin zheng Meiling Chen Fei Liu Wenhua Miao Renwu Zhou Patrick Cullen Zhenhai Xia Liming Dai Kostya(Ken)Ostrikov School of Food and Pharmacy Zhejiang Ocean UniversityZhoushan 316022China State Key Laboratory of Electrical Insulation and Power Equipment Center for Plasma BiomedicineXi'an Jiaotong UniversityXi'an 710049China School of Chemical and Biomolecular Engineering University of SydneySydney 2006Australia School of Chemistry and Physics and Centre for Materials Science Queensland University of TechnologyBrisbane 4000Australia Key Laboratory of Bio-based Polymeric Materials Technology and Application of Zhejiang Province Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China Australian Carbon Materials Centre(A-CMC) School of Chemical EngineeringUniversity of New South WalesSydneyNew South Wales 2052Australia

Cellulose macrofibers (MFs) are gaining increasing interest as natural and biodegradable alternatives to fossil-derived polymers for both structural and functional applications. However, simultaneously achieving their exceptional mechanical performance and desired functionality is challenging and requires complex processing. Here, we reported a one-step approach using a tension-assisted twisting (TAT) technique for MF fabrication from bacterial cellulose (BC). The TAT stretches and aligns BC nanofibers pre-arranged in hydrogel tubes to form MFs with compactly assembled structures and enhanced hydrogen bonding among neighboring nanofibers. The as-prepared BC MFs exhibited a very high tensile strength of 1 057 MPa and exceptional lifting capacity (over 340 000 when normalized by their own weight). Moreover, due to the volume expansion of BC nanofibers upon water exposure, BC MFs quickly harvested energy from environmental moisture to untwist the bundled networks, thus generating a torsional spinning with a peak rotation speed of 884 r/(min·m). The demonstrated rapid and intense actuation response makes the MFs ideal candidates for diverse humidity-response-based applications beyond advanced actuators, remote rain indicators, intelligent switches, and smart curtains.

关键词： Nanocellulose assembly Cellulose macrofibers Super-strong Humidity-responsive actuation Moisture Fast actuation

Effect of Nozzle Inclination Angle on Fuel-Air Mixing and Combustion in a Heavy Fuel Engine

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Fluid Dynamics & Materials Processing 2024年第2期20卷 365-382页

作者： Zhigang Wang bin zheng Peidong Zhao Baoli Wang Fanyan Meng Wenke Xu Jian Meng School of Transportation and Vehicle Engineering Shandong University of TechnologyZibo255049China

Heavy-fuel engines are widely used in UAVs(Unmanned Autonomous Vehicles)because of their reliability and high-power *** this study,a combustion model for an in-cylinder direct injection engine has been imple-mented using the AVL FIRE *** effects of the angle of nozzle inclination on fuel evaporation,mixture distribution,and combustion in the engine cylinder have been systematically studied at 5500 r/min and consider-ing full load cruise *** to the results,as the angle of nozzle inclination increases,the maximum combustion explosion pressure in the cylinderﬁrst increases and then it *** the angle of nozzle incli-nation is less than 45°,the quality of the mixture in the cylinder and the combustion performance can be improved by increasing the *** the angle of nozzle inclination is greater than 45°,however,the mixture unevenness increases slightly with the angle,leading to a deterioration of the combustion *** the angle of nozzle inclination is between 35°and 55°,the overall combustion performance of the engine is rela-tively *** the angle of nozzle inclination is 45°,the combustion chamber’s geometry and the cylinder’s airﬂow are well matched with the fuel spray,and the mixture quality is the *** with 25°,the peak heat release rate increases by 20%,and the maximum combustion burst pressure increases by 5.5%.

关键词： Aviation heavy fuel piston engine nozzle inclination angle combustion fuel-air mixing

Preoperative prediction of lymphovascular and perineural invasion in gastric cancer using spectral computed tomography imaging and machine learning

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World Journal of Gastroenterology 2024年第6期30卷 542-555页

作者： Hui-Ting Ge Jian-Wu Chen Li-Li Wang Tian-Xiu Zou bin zheng Yuan-Fen Liu Yun-Jing Xue Wei-Wen Lin Department of Radiology Fujian Medical University Union HospitalFuzhou 350001Fujian ProvinceChina Fujian Key Laboratory of Intelligent Imaging and Precision Radiotherapy for Tumors Fujian Medical UniversityFuzhou 350001Fujian ProvinceChina Digestive Hematological and Breast MalignanciesClinical Research Center for Radiology and Radiotherapy of Fujian ProvinceFuzhou 350001Fujian ProvinceChina Department of Radiation Oncology Fujian Medical University Union HospitalFuzhou 350001Fujian ProvinceChina Department of Diagnostic Radiology Fujian Medical University Union HospitalFuzhou 350001Fujian ProvinceChina School of Electrical and Computer Engineering University of OklahomaOklahomaOK 73019United States

BACKGROUND Lymphovascular invasion(LVI)and perineural invasion(PNI)are important prognostic factors for gastric cancer(GC)that indicate an increased risk of metastasis and poor *** preoperative prediction of LVI/PNI status could help clinicians identify high-risk patients and guide treatment ***,prior models using conventional computed tomography(CT)images to predict LVI or PNI separately have had limited *** CT provides quantitative enhancement parameters that may better capture tumor *** hypothesized that a predictive model combining clinical and spectral CT parameters would accurately preoperatively predict LVI/PNI status in GC *** To develop and test a machine learning model that fuses spectral CT parameters and clinical indicators to predict LVI/PNI status *** This study used a retrospective dataset involving 257 GC patients(training cohort,n=172;validation cohort,n=85).First,several clinical indicators,including serum tumor markers,CT-TN stages and CT-detected extramural vein invasion(CT-EMVI),were extracted,as were quantitative spectral CT parameters from the delineated tumor ***,a two-step feature selection approach using correlation-based methods and information gain ranking inside a 10-fold cross-validation loop was utilized to select informative clinical and spectral CT parameters.A logistic regression(LR)-based nomogram model was subsequently constructed to predict LVI/PNI status,and its performance was evaluated using the area under the receiver operating characteristic curve(AUC).RESULTS In both the training and validation cohorts,CT T3-4 stage,CT-N positive status,and CT-EMVI positive status are more prevalent in the LVI/PNI-positive group and these differences are statistically significant(P<0.05).LR analysis of the training group showed preoperative CT-T stage,CT-EMVI,single-energy CT values of 70 keV of venous phase(VP-70 keV),and the ratio of standardized iodine co

关键词： Spectral computed tomography Gastric cancer Lymphovascular invasion Perineural invasion

高层建筑框剪结构混凝土厚板转换层施工技术分析

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江西建材 2024年第5期 282-284页

作者：郑斌中国航发北京航空材料研究院

针对厚板转换层钢筋密集、浇筑量大等问题，文中以某大型公共建筑项目为例，对高层建筑框剪结构混凝土厚板转换层施工技术进行分析。结果表明，采用BIM技术进行钢筋模拟可为后续施工提供助益，上下部分层、上部分区分块的浇筑顺序能够... 详细信息

针对厚板转换层钢筋密集、浇筑量大等问题，文中以某大型公共建筑项目为例，对高层建筑框剪结构混凝土厚板转换层施工技术进行分析。结果表明，采用BIM技术进行钢筋模拟可为后续施工提供助益，上下部分层、上部分区分块的浇筑顺序能够有效保证混凝土的浇筑质量；同时，水平施工缝采用钢筋加强、高压冲刷，竖向施工缝应用快易收口网的方式能有效保证结合处的均匀、密实，避免发生渗漏风险。

关键词：高层建筑结构工程厚板转换层施工技术

创意人力资本视角的大学公共艺术教育经济效应分析——基于文献的评述

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北京交通大学学报（社会科学版） 2024年第2期23卷 152-161页

作者：郑彬北京交通大学艺术教育中心北京100044

公共艺术教育作为高等教育的组成部分,对大学生的全面发展具有良好的促进作用,有助于培养创新精神,训练创新思维,开发创新潜力。从经济角度来看,经济发展带动艺术发展,艺术发展促进经济繁荣。因而,如何看待艺术教育的经济效应是教育工... 详细信息

公共艺术教育作为高等教育的组成部分,对大学生的全面发展具有良好的促进作用,有助于培养创新精神,训练创新思维,开发创新潜力。从经济角度来看,经济发展带动艺术发展,艺术发展促进经济繁荣。因而,如何看待艺术教育的经济效应是教育工作者应该重视的重要课题。基于国外相关理论和研究,可以从微观与宏观、直接与间接两个层面分析公共艺术教育的经济效应及其传导机制,为公共艺术教育的经济效应分析构建一个系统的理论框架。研究认为,在微观层面,公共艺术教育作为一种创意人力资本投资,可通过认知效应、健康效应、情感行为效应和审美需求效应提升个体在创意经济时代的就业能力与文化艺术消费能力;在宏观层面,公共艺术教育不仅可以从供需两方面促进文化创意产业发展,还可通过促进科技与艺术的融合式创新、促进多样化人才的孵化集聚、改善人文社会环境,在加速创意人力资本实现收益的同时,释放消费潜力、加快产业升级、实现区域经济发展。加强高等学校的公共艺术教育,并重视公共艺术教育的经济效应,既是新时代高等教育发展的必然要求,也是推动经济高质量发展的全新探索。高校应充分理解和认识公共艺术教育的经济效应,加强顶层设计;创新公共艺术教育的内容和形式,形成公共艺术教育教学体系,让学生“走出去”;重视前沿多元的师资队伍建设,让师资“引进来”。

关键词：公共艺术教育经济效应创意人力资本创意经济文化创意产业

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中枢性性早熟临床实践指南的质量评价

中国现代应用药学 2024年第1期41卷 119-125页

作者：郑薇薇郑斌刘茂柏福建医科大学附属协和医院福州350001

目的了解中枢性性早熟临床实践指南与共识的现状,评价和分析其质量,为中枢性性早熟临床决策和指南共识的修订与完善提供参考。方法计算机检索PubMed、OVID、中国知网、万方数据库、国际指南联盟、Guidelines International Network(GIN)... 详细信息

目的了解中枢性性早熟临床实践指南与共识的现状,评价和分析其质量,为中枢性性早熟临床决策和指南共识的修订与完善提供参考。方法计算机检索PubMed、OVID、中国知网、万方数据库、国际指南联盟、Guidelines International Network(GIN)、National Institute for Health and Care Excellence(NICE)、Scottish Intercollegiate Guidelines Network(SIGN)、American Society of Clinical Oncology(ASCO)、American Urological Association(AUA)等中英文数据库和相关网站;检索时间从建库到2021年5月;由2名研究人员严格按照纳入与排除标准进行文献筛选,纳入临床实践指南。运用指南研究与评价工具(Appraisal of Guidelines for Research&Evaluation Ⅱ,AGREEⅡ)评价和分析其质量,对药物治疗推荐意见进行比较总结。结果本研究共纳入指南5篇。AGREEⅡ质量评价结果显示,6个领域的平均标准化得分:范围和目的86.6%、参与人员43.9%、严谨性22.3%、清晰性75.5%、应用性40.0%、独立性40.8%;4篇指南推荐等级为B级,1篇为C级。结论中枢性性早熟临床实践指南总体方法学质量中等偏低,应严格按照循证指南的制定标准及AGREEⅡ各领域要求,制定高质量中枢性性早熟循证临床实践指南。

关键词：中枢性性早熟指南 AGREEⅡ 质量评价

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基于时域卷积网络与注意力机制的车辆换道轨迹预测模型

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交通运输系统工程与信息 2024年第2期24卷 114-126页

作者：杨达刘家威郑斌孙峰西南交通大学交通运输与物流学院成都610031 威斯康星大学土木与环境工程学院美国威斯康星州麦迪逊市53706

精准的车辆轨迹预测模型可以为自动驾驶车辆提供其周围车辆的准确运动状态信息,进而判断本车与周围车辆短期内是否有发生冲突的可能性。本文提出一种基于时域卷积网络与注意力机制(Temporal Convolutional Networks with Attention mech... 详细信息

精准的车辆轨迹预测模型可以为自动驾驶车辆提供其周围车辆的准确运动状态信息,进而判断本车与周围车辆短期内是否有发生冲突的可能性。本文提出一种基于时域卷积网络与注意力机制(Temporal Convolutional Networks with Attention mechanism,TCN-Attention)的车辆换道轨迹预测模型。该模型以时域卷积网络作为当前输入的特征提取器,利用时间与空间注意力机制使模型在不同时间和空间位置之间建立动态关联,更准确地捕捉车辆之间的动态时空相关性,实现准确预测车辆换道轨迹。与传统单一车辆轨迹特征输入不同,本文通过对输入特征进行多维扩充与融合,进一步提高了轨迹预测准确率。此外,本文提出一种换道执行起止时刻定义方法更准确地确定数据集中的换道起止时刻。实验表明,本文所提模型能以高准确率预测变换车道轨迹,在整体效果上优于其他深度学习模型,与ConvLSTM (Convolution Long Short-Term Memory)相比,TCN-Attention的平均绝对误差(Mean Absolute Error,E_(MAE))降低了69.8%,均方根误差(Root Mean Square Error,E_(RMSE))降低了49.15%,平均绝对百分比误差(Mean Absolute Percentage Error,E_(MAPE))降低了14.24%。

关键词：交通工程轨迹预测 TCN-Attention 车辆换道

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