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河北省近40年耕地时空变化特征研究

河北地质大学学报 2024年第3期47卷 107-114页

作者：康宇佳安磊尚国琲河北地质大学土地科学与空间规划学院河北石家庄050031

为更好利用河北省的耕地资源,对河北省近40年耕地时空变化特征开展研究。以河北省耕地数据为基础,结合动态度、转移矩阵以及转移图谱等方法定量分析耕地变化特征。研究表明:1980—2020年,耕地是河北省最主要的土地资源,集中分布于南部... 详细信息

为更好利用河北省的耕地资源,对河北省近40年耕地时空变化特征开展研究。以河北省耕地数据为基础,结合动态度、转移矩阵以及转移图谱等方法定量分析耕地变化特征。研究表明:1980—2020年,耕地是河北省最主要的土地资源,集中分布于南部区域。耕地变化幅度最大的3个城市为保定、邯郸和石家庄,耕地变化幅度最小的城市为秦皇岛。从转入转出情况来看,1980—2020年,耕地流失方向主要为耕地→城镇用地,耕地共计流失26676km^(2),耕地来源主要有城镇用地、草地和林地,耕地共计转入18029km^(2)。1980—2020年,河北省耕地新增面积为18014km^(2),其中,张家口、承德、保定3个城市耕地新增面积最多,分别为4225km^(2)、3768km^(2)、1925km^(2);河北省耕地萎缩的面积为26661km^(2),其中,张家口、承德、保定3个城市耕地萎缩的面积最大,分别为5017km^(2)、4190km^(2)、3064km^(2)。本研究可为耕地占补政策提供数据支撑。

关键词：耕地时空变化河北省

Robust Approximation-Based Event-Triggered MPC for Constrained Sampled-Data Systems

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Journal of Systems Science & Complexity 2021年第6期34卷 2109-2124页

作者： WANG Tao kang yu LI Pengfei ZHAO yun-Bo yu Peilong Department of Automation University of Science and Technology of ChinaHefei 230027China State Key Laboratory of Fire Science University of Science and Technology of ChinaHefei 230027China Institute of Advanced Technology University of Science and Technology of ChinaHefei 230027China College of Information Engineering Zhejiang University of TechnologyHangzhou 310023China

In this paper,an approximation-based event-triggered model predictive control(AETMPC)strategy is proposed to implement event-triggered model predictive control for continuous-time constrained nonlinear systems under the digital *** the AETMPC strategy,both of the optimal control problem(OCP)and the triggering conditions are defined in a discrete-time manner based on approximate discrete-time models,while the plant under control is continuous *** doing so,sensing load is alleviated because the triggering condition does not need to be checked continuously,and the computation of the OCP is simpler since which is calculated in the discrete-time ***,robust constraints are satisfied in a continuous-time sense by taking inter-sampling behavior into consideration,and a novel constraint tightening approach is presented ***,the feasibility of the AETMPC strategy is analyzed and the associated stability of the overall system is ***,this strategy is validated by a numerical example.

关键词： Approximations event-triggered control model predictive control sampled-data systems

High-emitter identification for heavy-duty vehicles by temporal optimization LSTM and an adaptive dynamic threshold

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Frontiers of Information Technology & Electronic Engineering 2023年第11期24卷 1633-1646页

作者： Zhenyi XU Renjun WANG Yang CAO yu kang Institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefei 230088China AHU-IAI AI Joint Laboratory Anhui UniversityHefei 230601China Department of Automation University of Science and Technology of ChinaHefei 230027China Institute of Advanced Technology University of Science and Technology of ChinaHefei 230088China

Heavy-duty diesel vehicles are important sources of urban nitrogen oxides(NOx)in actual applications for environmental compliance,emitting more than 80%of NOx and more than 90%of particulate matter(PM)in total vehicle *** detection and control of heavy-duty diesel emissions are critical for protecting public ***,vehicles on the road must be regularly tested,every six months or once a year,to filter out high-emission mobile sources at vehicle inspection ***,it is difficult to effectively screen high-emission vehicles in time with a long interval between annual inspections,and the fixed threshold cannot adapt to the dynamic changes of vehicle driving *** on-board diagnostic device(OBD)is installed inside the vehicle and can record the vehicle’s emission data in real *** this paper,we propose a temporal optimization long short-term memory(LSTM)and adaptive dynamic threshold approach to identify heavy-duty high-emitters by using OBD data,which can continuously track and record the emission status in real ***,a temporal optimization LSTM emission prediction model is established to solve the attention bias discrepancy problem on time steps that is caused by the large number of OBD data streams in ***,the concentration prediction error sequence is detected and distinguished from the anomalous emission contexts using flexible criteria,calculated by an adaptive dynamic threshold with changing driving ***,a similarity metric strategy for the time series is introduced to correct some pseudo anomalous *** on three real OBD time-series emission datasets demonstrate that our method can achieve high accuracy anomalous emission identification.

关键词： High-emitter identification Temporal optimization On-board diagnostic device(OBD) Dynamic threshold

Projection-based 3D bioprinting for hydrogel scaffold manufacturing

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Bio-Design and Manufacturing 2022年第3期5卷 633-639页

作者： yuan Sun kang yu Qing Gao Yong He State Key Laboratory of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310027China Key Laboratory of 3D Printing Process and Equipment of Zhejiang Province School of Mechanical EngineeringZhejiang UniversityHangzhou 310027China Engineering for Life Group(EFL) Suzhou 215101China Key Laboratory of Materials Processing and Mold Zhengzhou UniversityZhengzhou 450002China Cancer Center Zhejiang UniversityHangzhou 310058China

Projection-based 3D bioprinting(PBP):a powerful method to fabricate 3D cellular structures Three-dimensional(3D)bioprinting has played an important role in tissue engineering and regenerative medicine areas over the past decade[1].Different from traditional cell cultures in Petri dishes,3D bioprinting can build bionic structures with a better potential to become artificial organ substitutes[2–4].With the development of photocurable biomaterials,the projection-based 3D printing method has been successfully applied in biological research[5,6].

关键词： printing biomaterials projection

Optimization Algorithms for Predictive Control Approach to Networked Bilinear Systems

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自动化学报 2017年第7期43卷 1234-1240页

作者： Binglin Wang yu kang Jiahu Qin Yanmei Li Department of Automation University of Science and Technology of China Hefei 230027 China State Key Laboratory of Fire Science Department of Automation Institute of Advanced Technology University of Science and Technology of China Hefei 230027 China and also with the Key Laboratory of Technology in Geo-Spatial Information Processing and Application System Chi- nese Academy of Sciences Beijing 100190 China Physics and Electronic Engineering Anqing Normal University Anqing 246011 China

This paper is concerned with the networked predictive control of discrete-time bilinear systems. To deal with the network-induced communication delay that exists in both forward channel (controller to actuator) and feedback channel (sensor to controller), a bilinear networked predictive control scheme is proposed. Then a non-convex optimization problem of solving the predictive control sequence is presented, for which two gradually-optimized algorithms are proposed based on the special structure of bilinear system dynamics model. The numerical simulation indicates that the resulting predictive control sequence can compensate for the network-induced issues actively, which proves the effectiveness of the proposed predictive control strategy.

关键词：离散双线性系统预测控制策略逐步优化算法网络化系统动力学模型控制序列反馈通道通信延迟

老年2型糖尿病患者肌肉衰减现状及其糖尿病自我管理行为研究

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中华临床营养杂志 2024年第2期32卷 71-79页

作者：李敏王丽屠馨怡周菁颖董颖越李菁于康中国医学科学院、北京协和医学院护理学院北京100144 北京市丰台区方庄社区卫生服务中心北京100078 浙江大学医学院附属第二医院护理部杭州310009 北京大学护理学院北京100191 北京协和医院内分泌科北京100730 北京协和医院临床营养科北京100730

目的调查老年2型糖尿病(type 2 diabetes mellitus,T2DM)患者肌肉衰减状况及自我管理的现状,探究糖尿病自我管理对肌肉衰减的危险因素识别情况。方法采用便利抽样法,选取2023年3至9月在北京市某社区卫生服务中心就诊的284例老年T2DM患... 详细信息

目的调查老年2型糖尿病(type 2 diabetes mellitus,T2DM)患者肌肉衰减状况及自我管理的现状,探究糖尿病自我管理对肌肉衰减的危险因素识别情况。方法采用便利抽样法,选取2023年3至9月在北京市某社区卫生服务中心就诊的284例老年T2DM患者为研究对象,根据2019年亚洲肌少症工作组专家共识对患者进行肌肉衰减状况筛查和相关健康检查,采用一般资料调查表、糖尿病自我管理行为量表等进行问卷调查。根据患者是否存在肌肉衰减状况将其分为无肌肉衰减状况组和有肌肉衰减状况组。结果284例老年T2DM患者肌肉衰减状况的发生率为48.9%,肌少症的患病率为15.9%。有肌肉衰减状况组女性、70岁以上、有久坐习惯的患者占比显著高于无肌肉衰减状况组,优质蛋白摄入、四肢骨骼肌肌肉质量指数、握力、6 m步速显著低于无肌肉衰减状况组(P<0.05);二元Logistic回归分析显示年龄、饮酒情况、久坐、优质蛋白摄入是老年T2DM患者肌肉衰减状况的影响因素(P<0.05);两组在自我管理行为总分和运动维度得分的差异有统计学意义(P<0.05);单因素分析结果显示,不同握力和6 m步速患者的糖尿病自我管理行为差异有统计学意义(P<0.05);多元线性回归分析显示,握力和6 m步速是老年T2DM患者运动管理行为的影响因素(P<0.05)。结论老年T2DM患者肌少症的发生率较高,且其糖尿病自我管理水平中等偏下。在临床工作中,医护人员要更多关注70岁以上、有久坐习惯、优质蛋白摄入较少以及女性患者,建议通过握力和6 m步速测试对老年T2DM患者进行肌肉衰减状况的初筛,尽早识别风险并开展老年T2DM患者针对性的健康管理,促进患者良好自我管理行为的形成。

关键词： 2型糖尿病肌肉衰减握力 6米步速自我管理行为

MRI鉴别宫颈腺体叶状增生与宫颈胃型腺癌的价值

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中国癌症杂志 2024年第4期34卷 380-388页

作者：马凤华姜安绮陈奕清徐丛剑康玉复旦大学附属妇产科医院放射科上海200011 复旦大学附属妇产科医院妇科上海200011 上海市女性生殖内分泌相关疾病重点实验室上海200011

背景与目的:宫颈胃型腺癌(gastric-type endocervical adenocarcinoma,G-EAC)是一种少见的宫颈腺癌,临床表现不典型,病灶隐匿,极易漏诊、误诊,患者预后差;而宫颈腺体叶状增生(lobular endocervical glandular hyperplasia,LEGH)及非典型LEGH(atypical lobular endocervical glandular hyperplasia,aLEGH)是G-EAC的癌前病变,与G-EAC存在临床、病理学及影像学等诸多重叠,术前诊断极具挑战性。本文旨在分析宫颈囊实性病变的磁共振成像(magnetic resonanceimaging,MRI)表现与病理学诊断结果的相关性,以提高LEGH与G-EAC鉴别诊断的准确性。方法:收集2016年7月—2023年8月在复旦大学附属妇产科医院就诊的37例LEGH和53例G-EAC患者的临床、影像学及病理学资料。采用χ^(2)检验或Fisher精确概率法等进行统计学分析,采用logistic回归进行多因素分析,采用受试者工作特征(receiver operator characteristic,ROC)曲线进行效能评价。结果:LEGH和G-EAC两组间患者年龄、症状、病灶范围、大小、成分、强化程度、宫颈间质环、子宫内膜累及、淋巴结肿大、宫腔积液差异有统计学意义(P<0.05)。LEGH及aLEGH组病灶位于宫颈黏膜层,主要表现为大、微小囊混合型或密集微小囊型(32/37),囊壁多明显强化(31/37);而G-EAC组中多累及宫颈肌层(42/53),多见实性成分(52/53)和低信号间质环中断或消失(46/53)。Logistic回归分析结果显示,病灶实性成分(OR=50.064)和宫颈间质环中断(OR=40.180)可作为预测G-EAC的显著MRI特征。综合病灶大小、成分、强化程度、宫颈间质环和子宫内膜累及5个特征,对诊断G-EAC的效能采用ROC分析,曲线下面积(area under curve,AUC)为0.970(95%CI:0.931~1.008)。结论:结合宫颈囊实性病变的多个MRI征象有助于鉴别LEGH与G-EAC。

关键词：宫颈腺体叶状增生宫颈胃型腺癌癌前病变磁共振成像鉴别诊断

Issues about the nocebo phenomena in clinics

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Chinese Medical Journal 2009年第9期122卷 1102-1106页

作者： WU Zhen-yu LI kang Department of Health Statistics Harbin Medical UniversityHarbin Heilongjiang 150081 China

During clinical work, some side-effects may occur to patients, part of which are caused by the specific pharrnacological effects of drugs and some of which are non-specific. Although these phenomena happen from time to time, burdening the anguish and expenditure of patients, their nature is still less understood. Recently, as the research of the placebo effect become deeper and deeper, clinicians and researchers have gradually realized that mind plays an important role in the occurrence of non-specific side-effects, which is called ＂nocebo effect＂ professionally, the evil side of placebo effect. This article would expatiate on nocebo effect in detail from several aspects, such as its mechanism, effect, influencing factors and discuss how to make it known and treated in clinical practice and clinical trials.

关键词： nocebo placebo drug side-effect clinical trial

高二氧化碳浓度气氛下不同粒径生料热分解试验研究

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水泥 2024年第8期 38-42页

作者：康宇卜昌盛李安平中材国际智能科技有限公司江苏南京210036 南京市水泥工业绿色制造工程技术研究中心江苏南京210036 南京师范大学能源与机械工程学院江苏南京210023

通过高二氧化碳浓度气氛下大热重试验和悬浮炉生料热分解试验,研究不同粒度范围(<45μm,45~75μm,75~250μm)的生料热分解特性。结果显示:相同试验条件下,粒度越细,生料热分解温度相对越低、分解完成时间越短,但三种粒径范围生料热分解... 详细信息

通过高二氧化碳浓度气氛下大热重试验和悬浮炉生料热分解试验,研究不同粒度范围(<45μm,45~75μm,75~250μm)的生料热分解特性。结果显示:相同试验条件下,粒度越细,生料热分解温度相对越低、分解完成时间越短,但三种粒径范围生料热分解性能差异性较小,表明在微米级范围内,粒度对生料热分解性能的影响有限。

关键词：二氧化碳浓度生料粒径分解