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优化SPECIAL 1H-MR波谱并结合自制LCModel软件模拟代谢物光谱数据集定量分析离体猪肝葡萄糖
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作者 钟梓杰 沈智威 林黛英 《中国介入影像与治疗学》 北大核心 2025年第4期273-278,共6页
目的 优化SPECIAL1H-MR波谱(MRS)扫描参数,并观察以之结合自制LCModel软件模拟代谢物光谱数据集(B集)定量分析离体猪肝葡萄糖(Glc)的可行性。方法 利用生理盐水将鱼肝油、Glc及胆碱配置成Glc浓度不同(10、20、30、40、50 mmol/L)而鱼肝... 目的 优化SPECIAL1H-MR波谱(MRS)扫描参数,并观察以之结合自制LCModel软件模拟代谢物光谱数据集(B集)定量分析离体猪肝葡萄糖(Glc)的可行性。方法 利用生理盐水将鱼肝油、Glc及胆碱配置成Glc浓度不同(10、20、30、40、50 mmol/L)而鱼肝油(0.125 mg/ml)及胆碱(100 mmol/L)浓度固定的混合溶液,以试管模型模拟肝脏代谢物;每种Glc浓度各设5个、共配置25个试管模型。以不同参数SPECIAL序列扫描试管模型,获得1H-MRS图像。利用LCModel软件分别基于自带代谢物基础集(A集)及B集分析试管模型SPECIAL序列数据,生成SPECIAL1H-MRS图像并获得其信噪比(SNR)及标准差百分比(SD%)、Glc信号强度;根据SNR及SD%评估SPECIAL1HMRS图像质量,以选择最优扫描参数,分析以最优参数结合B集所获试管模型Glc信号强度与Glc浓度的相关性。以最优SPECIAL序列扫描离体猪肝(n=5),行更新脂肪抑制(FS)-SPECIAL序列扫描,基于B集获得相应1H-MRS图像并评估其质量。结果SPECIAL序列最优扫描参数为TR3500ms、TE4.42ms、TM20.00ms、重复次数(averages)为256,以之结合B集所获试管模型SPECIAL1H-MRS的SNR达40.5±1.1,SD%为(13.5±1.0)%,谱线更清晰,基线更平稳,Glc峰分辨率更高。以1H-MRS所获试管模型Glc信号强度与Glc浓度呈正相关(r=0.997,P<0.001)。离体猪肝SPECIAL1H-MRS的SNR为24.0±2.7,SD%为(13.5±1.1)%,而FS-SPECIAL1H-MRS质量较高,SNR为29.5±2.3,SD%为(4.0±0.8)%,可见亚甲基峰被抑制而Glc峰分辨率更高。结论利用参数优化SPECIAL1H-MRS结合自制LCModel软件模拟数据集可准确定量分析离体猪肝Glc。 展开更多
关键词 肝脏 葡萄糖代谢 磁共振波谱学 special序列
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On The Role Of Needs Analysis In ESP Course And Its Implications For Specialized EnglishReading Cour
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作者 刘浩 庞云青 《陕西师范大学学报(哲学社会科学版)》 CSSCI 北大核心 1999年第S1期149-152,共4页
CLCNumber:H319.3Documentcode:AArtrcleID:1000┐5293(1999)Sup.┐0150┐04SpecializedEnglishreadingistheseniorstage... CLCNumber:H319.3Documentcode:AArtrcleID:1000┐5293(1999)Sup.┐0150┐04SpecializedEnglishreadingistheseniorstageincolegeEnglishte... 展开更多
关键词 needs ANALYSIS ESP specialized ENGLISH READING SYLLABUS
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Frame property of unequal storey height with specially shaped columns under cyclic loading 被引量:6
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作者 王铁成 张学辉 《Journal of Central South University》 SCIE EI CAS 2010年第6期1364-1369,共6页
A 1/3-scale reinfored concrete(RC) frame of unequal storey height with specially shaped columns was tested under low frequency cyclic loading.The damage characteristic,bearing capacity,deformation capacity and ductili... A 1/3-scale reinfored concrete(RC) frame of unequal storey height with specially shaped columns was tested under low frequency cyclic loading.The damage characteristic,bearing capacity,deformation capacity and ductility were analyzed.The restoring force model of the frame was obtained based on the study of the hysteresis curve measured in experiment,and the stiffness degeneration characteristics of every storey of the frame were analyzed.Finally the accumulated damage was analyzed with the damage assessment model.It is shown that the seismic behavior of this frame of unequal storey height with specially shaped columns is generally good,but the bottom of first floor column is a weak part,which should be paid more attention in design,and the restoring force model derived from this experiment can be seen as a valuable guide for design and non-linear finite element analysis for this kind of structure. 展开更多
关键词 FRAME specially shaped column restoring force accumulated damage seismic behavior
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Recognition and depiction of special geologic bodies of Member 3 of Dongying Formation in Littoral Slope Zone,Qikou Sag 被引量:4
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作者 陈思 王华 +6 位作者 周立宏 黄传炎 任培罡 王家豪 廖远涛 向雪梅 夏存银 《Journal of Central South University》 SCIE EI CAS 2011年第3期898-908,共11页
The purpose of this study is to forecast the profitable oil and gas reservoir,which is the key of finding hydrocarbon,based on the conception of special geologic bodies.With the guiding methodology of the research thi... The purpose of this study is to forecast the profitable oil and gas reservoir,which is the key of finding hydrocarbon,based on the conception of special geologic bodies.With the guiding methodology of the research thinking of integration of point-line-surface by using the methods and techniques of logging,seismic,seismic attribute,and logging constrained inversion in 3D data volume,the special geologic bodies of Member 3 of Dongying Formation in Littoral Slope Zone of Qikou Sag,which has important hydrocarbon exploration potential,are recognized and described under the constraint of sequence stratigraphic framework.As a result,the developed scale,geometric shape and space distribution feature of the special geologic bodies are forecasted;the inner structure and sequence structure patterns of the geologic bodies are also ascertained.From the lowstand system tract (LST) and lacustrine expanding system tract (EST) to the highstand system tract (HST),the geologic bodies have evolved from relative centralization of lake basin reducing period to three relative dispersive isolated parts of broad lake basin period.According to the relevance and regularity of the development of geologic bodies,the conclusions can be obtained that three types of potential profitable reservoir traps,including the lithologic lens traps,lithologic updip pinchout traps and structural-lithologic composite traps,are forecasted.In addition,scientific basis for further hydrocarbon exploration in new area (few-well area and no-well area) is offered in the guidance of sequence stratigraphic model. 展开更多
关键词 Qikou Sag Littoral Slope Zone Dongying Formation special geologic bodies
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Calibration of split Hopkinson pressure bar system with special shape striker 被引量:1
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作者 周子龙 洪亮 +1 位作者 李启月 刘志祥 《Journal of Central South University》 SCIE EI CAS 2011年第4期1139-1143,共5页
In order to present basic guidance for system calibration of split Hopkinson pressure bar(SHPB) with the special shape striker,wave characteristics and dynamic responses of SHPB under striker impact were analyzed.Stre... In order to present basic guidance for system calibration of split Hopkinson pressure bar(SHPB) with the special shape striker,wave characteristics and dynamic responses of SHPB under striker impact were analyzed.Stress generated by the special shape striker tends to have a half-sine waveform and has little wave dispersion during its propagation.Impact velocities of the special shape striker and peak values of generated stress still have linear relation but with a different coefficient from that of cylindrical strikers.From stress histories on the surfaces of the input bar impacted by the special shape striker off-axially and obliquely,it is found that the misalignment impacts usually trigger wave distortion and amplitude decrease,which can be used to identify the poor system adjustment.Finally,the system calibration of SHPB with the special shape striker can be classified into four steps:system adjustment,wave distortion identification,measurement calibration and transmission calibration,where the measurement calibration factor and transmission calibration factor are elaborated and redefined. 展开更多
关键词 split Hopkinson pressure bar special shape striker system calibration misalignment impact
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Recognition and Depiction of the Special Geologic Bodies of the Member 3 of Dongying Formation in Littoral Slope Zone,Qikou Sag
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作者 Si Chen~(1,2),Hua Wang~1,Chuanyan Huang~(1,2),Peigang Ren~1,Jiahao Wang~1,Yuantao Liao~1,Xuemei Xiang~1,Cunyin Xia~1 1.Key Laboratory of Tectonics and Petroleum Resources,Ministry of Education,Faculty of Earth Resources,China University of Geosciences(Wuhan),Wuhan 430074,China. 2.State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Wuhan 430074, China 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期143-143,共1页
The key of finding hydrocarbon reservoir is to find the profitable oil and gas reservoir.This paper uses the conception of"special geologic bodies"to study the profitable reservoir.Constrained by the sequenc... The key of finding hydrocarbon reservoir is to find the profitable oil and gas reservoir.This paper uses the conception of"special geologic bodies"to study the profitable reservoir.Constrained by the sequence stratigraphy framework,this paper recognizes and describes the special geologic bodies of the Member 3 of Dongying Formation in Littoral Slope Zone of Qikou Sag,which have important 展开更多
关键词 Qikou Sag LITTORAL SLOPE ZONE Dongying Formation special GEOLOGIC BODIES
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Catalyst Pellet Shape Specialization for Ethylene Acetoxidation to Vinyl Acetate
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作者 Ju Mengjoe Xu Ke +1 位作者 Wang Shangdi (Department of Chemical Engineering Zhejiang University)(Hangzhou,310027 China) 《高校化学工程学报》 EI CAS CSCD 1994年第S1期72-76,共5页
CatalystPelletShapeSpecializationforEthyleneAcetoxidationtoVinylAcetateJuMengjoe;XuKe;WangShangdi(Department... CatalystPelletShapeSpecializationforEthyleneAcetoxidationtoVinylAcetateJuMengjoe;XuKe;WangShangdi(DepartmentofChemicalEnginee... 展开更多
关键词 PELLET SHAPE specialIZATION ETHYLENE Acetoxidation CATALYST Activity Distribution
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Effects of pooling,specialization,and discretionary task completion on queueing performance
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作者 JIANG Houyuan 《运筹学学报(中英文)》 CSCD 北大核心 2024年第3期81-96,共16页
Pooling,unpooling/specialization,and discretionary task completion are typical operational strategies in queueing systems that arise in healthcare,call centers,and online sales.These strategies may have advantages and... Pooling,unpooling/specialization,and discretionary task completion are typical operational strategies in queueing systems that arise in healthcare,call centers,and online sales.These strategies may have advantages and disadvantages in different operational environments.This paper uses the M/M/1 and M/M/2 queues to study the impact of pooling,specialization,and discretionary task completion on the average queue length.Closed-form solutions for the average M/M/2 queue length are derived.Computational examples illustrate how the average queue length changes with the strength of pooling,specialization,and discretionary task completion.Finally,several conjectures are made in the paper. 展开更多
关键词 queuing systems pooling specialIZATION discretionary task completion average queue length
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Prolog to the Special Issue on System Simulation
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作者 Li, Bohu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1993年第4期1-1,共1页
System simulation is a comprehensive technology, which makesdynamic experiments on a system by means of system model(computerized / semi-physical / physical mode) under certainexperimental condition. Today, system sim... System simulation is a comprehensive technology, which makesdynamic experiments on a system by means of system model(computerized / semi-physical / physical mode) under certainexperimental condition. Today, system simulation has heen de-veloped into a comprehensive experimental discipline based on 展开更多
关键词 SIMULATION Prolog to the special Issue on System Simulation
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Control Engineering of China Special Issue on "Control Systems Engineering"
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《控制工程》 CSCD 北大核心 2016年第12期1859-1860,共2页
Control systems contribute to every aspect of modem society.In our life control systems exist in almost everywhere such as toasters,VCRs and smart phones.In science and technology,control systems already have widespre... Control systems contribute to every aspect of modem society.In our life control systems exist in almost everywhere such as toasters,VCRs and smart phones.In science and technology,control systems already have widespread applications,for example,steering ships,guiding missiles and driving driverless cars in the near future.In all the control systems,systems are the key platform where control should be put into.It is at the system level that control shows its values.Extracting and formulating 展开更多
关键词 Control Engineering of China special Issue on Control Systems Engineering
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The Secretariat of Special Committee for Water Jet Technology
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《中国安全科学学报》 CAS CSCD 1999年第S1期99-99,共1页
关键词 The Secretariat of special Committee for Water Jet Technology
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Editorial of Special Issue
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作者 Daniel W. Wong 《中国康复理论与实践》 CSCD 2006年第9期737-737,共1页
I am very pleased to have edited these nine (9) articles for publication authored by Chinese Americans professors from the United Sates and with the contribution of some of their former and current doctoral students i... I am very pleased to have edited these nine (9) articles for publication authored by Chinese Americans professors from the United Sates and with the contribution of some of their former and current doctoral students in rehabilitation psychology and rehabilitation counseling studies. The aim of this special issue to be published in China is to provide the readers of the Chinese Journal of Rehabilitation Theory and Practice worldwide with some pertinent and updated issues in the field of rehabilitation and disability research in the United States. This issue may serve the purpose of the beginning of information and academic exchange between the United Stated and China academic professionals, students and other readers with respect to the fields of rehabilitation and disability research. 展开更多
关键词 Editorial of special Issue
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Prolog to the Special Issue on System Simulation
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《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1994年第3期1-1,共1页
Prolog to the Special Issue on System SimulationSimulationplaysanincreasinglyimportantroleinthedevelopment,t... Prolog to the Special Issue on System SimulationSimulationplaysanincreasinglyimportantroleinthedevelopment,testandtrainingofm... 展开更多
关键词 Prolog to the special Issue on System Simulation
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Prolog to the Special Section on Systems Science and Engineering
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作者 Yu Jingyuan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1993年第2期1-1,共1页
In the last decade and more, systems engineering and systems sciencehave been rapidly developed and applied in China. Scientists and ex-perts involved have achieved remarkable successes both in developingtheories of s... In the last decade and more, systems engineering and systems sciencehave been rapidly developed and applied in China. Scientists and ex-perts involved have achieved remarkable successes both in developingtheories of systems science and in promoting applications of systemsengineering. In theories, they not only have advanced a clear and com- 展开更多
关键词 Prolog to the special Section on Systems Science and Engineering
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SPECIAL FEATURES OF BUSINESS ENGLISH
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作者 曹广裕 《国际商务研究》 1983年第1期38-42,共5页
Business English is an important tool used by importers and exporters innegotiating business with their customers abroad and drafting letters and commercialdocuments.Just like literary or scientific Engliush,it has it... Business English is an important tool used by importers and exporters innegotiating business with their customers abroad and drafting letters and commercialdocuments.Just like literary or scientific Engliush,it has its own characteristics.In thisarticle,owing to the limited space,I shall discuss only some of its special points inlanguage and euphemistic expressions. 展开更多
关键词 special FEATURES OF BUSINESS ENGLISH
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Application and Pullback of the Risk- assumption Principle under Special Circumstances
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作者 Yang Lin Wan Rong 《学术界》 CSSCI 北大核心 2014年第10期268-272,共5页
The risk-assumption principle in infringement is widely used in sport injuries,which is accepted in both the theoretical circle and the juridical practice in China. If the personal injury on the sports ground is not c... The risk-assumption principle in infringement is widely used in sport injuries,which is accepted in both the theoretical circle and the juridical practice in China. If the personal injury on the sports ground is not caused by wrongful conducts,the risk-assumption principle is applied,and the doer does not assume compensation liability. If the personal injury is caused by illegality or purposeful illegality to cause personal injury,the risk-assumption principle shall be pulled back totally or partially,and the fault-offset principle and fairly-share-loss principle shall be applied to balance the interests of the two parties. However,under some special circumstances,it is difficult to judge whether there are wrongly conducts; fromthe controversial sports phenomena and sports subjects,this paper analyzes the application and pullback of the risk-assumption principle under some special circumstances. 展开更多
关键词 风险 应用 人身伤害 运动损伤 赔偿责任 人身伤亡 补偿原则 网络连接
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特种无人机创新应用与关键技术发展研究 被引量:5
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作者 项昌乐 徐彬 +5 位作者 唐寿星 樊伟 孙寒 刘润江 文行健 芮超 《中国工程科学》 北大核心 2025年第2期62-72,共11页
特种无人机指为满足军事国防、应急救援、特种工业等领域的特殊任务需求,专门设计、改装或配备特殊设备的专用无人机,拥有超越普通无人机的高机动、强适应与集成任务能力,在经济建设、国防安全等方面能够承担关键任务。本文从特种无人... 特种无人机指为满足军事国防、应急救援、特种工业等领域的特殊任务需求,专门设计、改装或配备特殊设备的专用无人机,拥有超越普通无人机的高机动、强适应与集成任务能力,在经济建设、国防安全等方面能够承担关键任务。本文从特种无人机装备的传统构型与创新构型两个维度出发,深入剖析了国内外特种无人机技术的研究现状与发展趋势,辨识了特种无人机在军事国防、应急救援、特种工业等领域中的典型任务能力需求及面临的挑战,进一步梳理了特种无人机技术体系,涵盖特种平台、智能控制、指控保障3个核心方向以及细分的技术类型。从发展布局统筹、未来研究方向两个层面提出了我国特种无人机技术与装备发展建议,以推进特种无人机装备深度融入并有力支撑国防现代化建设、经济社会高质量发展的战略目标。 展开更多
关键词 特种无人机 特种平台 智能控制 指控保障 跨域机动
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我国静脉治疗安全的分析与思考 被引量:1
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作者 李春燕 李旭英 +2 位作者 林琴 王蕾 杜鹃 《中国护理管理》 北大核心 2025年第3期321-325,共5页
文章基于我国静脉治疗领域的最新政策与技术发展,系统分析了老龄化加剧、日间化疗模式推广、输液工具多样化等挑战,探讨了信息技术融合、学科协作模式创新、专科人才培养等应对策略。通过思考与分析,提出规范化、智能化的静脉治疗发展路... 文章基于我国静脉治疗领域的最新政策与技术发展,系统分析了老龄化加剧、日间化疗模式推广、输液工具多样化等挑战,探讨了信息技术融合、学科协作模式创新、专科人才培养等应对策略。通过思考与分析,提出规范化、智能化的静脉治疗发展路径,旨在为提升静脉治疗安全性和护理质量提供理论参考。 展开更多
关键词 静脉治疗安全 信息技术应用 多学科协作 专科护士培养
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平台用工劳动关系认定的从属性标准——基于3016件涉平台劳动争议案件的实证研究 被引量:17
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作者 王蓓 覃秋令 《山东大学学报(哲学社会科学版)》 北大核心 2025年第1期85-96,共12页
通过研究中国裁判文书网9年间共3016份涉平台用工案件判决书,发现平台用工加剧了劳动关系的模糊化和隐蔽化,法官选择从属性标准的要件与要素时任意性较大,从属性标准的解释倾向不同导致裁判尺度宽严不一。究其原因,主要在于传统的形式... 通过研究中国裁判文书网9年间共3016份涉平台用工案件判决书,发现平台用工加剧了劳动关系的模糊化和隐蔽化,法官选择从属性标准的要件与要素时任意性较大,从属性标准的解释倾向不同导致裁判尺度宽严不一。究其原因,主要在于传统的形式审查理念存在弊端、从属性标准的适用规则不完善,以及两种相互矛盾的解释路径并存。未来需充分考虑平台用工的异质性,在理念层面对从属事实进行实质性审查,在规则层面通过司法解释明确“要件+要素”模式的一般标准,在司法层面明确个案价值平衡的特殊认定标准,以多层指标构建平台用工劳动关系认定的体系化规范。 展开更多
关键词 劳动关系 从属性理论 认定标准 平台用工 特殊认定标准
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职业教育专业教学标准的基本属性、要素内涵与主要特点 被引量:7
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作者 李志宏 江小明 +1 位作者 荀莉 刘义国 《中国职业技术教育》 北大核心 2025年第3期5-12,共8页
伴随着我国中高本衔接的现代职业教育体系的建立与完善,国家层面一直在建设与之配套的职业教育教学标准体系,其中,专业教学标准是整个教学标准体系的重要组成部分。为进一步推进职业教育高质量发展,提高职业学校办学效能,应准确把握新... 伴随着我国中高本衔接的现代职业教育体系的建立与完善,国家层面一直在建设与之配套的职业教育教学标准体系,其中,专业教学标准是整个教学标准体系的重要组成部分。为进一步推进职业教育高质量发展,提高职业学校办学效能,应准确把握新版专业教学标准的基本属性和要素内涵,明晰标准研制的主要特点,为全面推动新版专业教学标准落地实施提供重要的理论支撑和实践依据。 展开更多
关键词 职业教育 专业教学标准 中高本一体化
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