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四川地区儿童臀肌挛缩症调查报告 被引量:41
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作者 彭明惺 周素华 +12 位作者 周锡华 刘文英 汪静 罗启成 周碧华 王维平 蒋忠 孙新一 王东 鲜于剑波 朱延庚 郑宝玲 蔡蓉 《中华小儿外科杂志》 CSCD 1989年第6期356-358,共3页
1987年10月至1988年4月,作者在13630位3~12岁儿童的流行病学调查中,检出注射性臀肌挛缩症患者137例.在5688以生理盐水或注射用水稀释的青霉素作臀肌注射的儿童中检出患者2例;而7942例以苯甲醇稀释的青霉素作注射的儿童中检出患者135例... 1987年10月至1988年4月,作者在13630位3~12岁儿童的流行病学调查中,检出注射性臀肌挛缩症患者137例.在5688以生理盐水或注射用水稀释的青霉素作臀肌注射的儿童中检出患者2例;而7942例以苯甲醇稀释的青霉素作注射的儿童中检出患者135例.前者患病率为0.035%,后者为1.7%,两者相差48倍以上,此结果不仅验证了注射因素确系臀肌挛缩的病因,还发现苯甲醇青霉素溶液是重要的致病因子.且其浓度愈高,针数愈多,致病力亦愈强.如今后放弃使用苯甲醇,尤其是2%的苯甲醇作青霉素溶媒可望大幅度降低发病率. 展开更多
关键词 四川地区 儿童 注射性臀肌挛缩症 调查报告 Sichuan Province CHILDREN BENZYL alcohol 青霉素溶媒 苯甲醇 CHILDREN distilled water 流行病学调查 患者 significant 注射用水 致病因子 稀释 臀肌注射 生理盐水 related
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An assessment of global ocean wave energy resources over the last 45 a 被引量:25
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作者 ZHENG Chongwei SHAO Longtan +4 位作者 SHI Wenli SU Qin LIN Gang LI Xunqiang CHEN Xiaobin 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第1期92-101,共10页
Against the background of the current world facing an energy crisis,and human beings puzzled by the problems of environment and resources,developing clean energy sources becomes the inevitable choice to deal with a cl... Against the background of the current world facing an energy crisis,and human beings puzzled by the problems of environment and resources,developing clean energy sources becomes the inevitable choice to deal with a climate change and an energy shortage.A global ocean wave energy resource was reanalyzed by using ERA-40 wave reanalysis data 1957–2002 from European Centre for Medium-Range Weather Forecasts(ECMWF).An effective significant wave height is defined in the development of wave energy resources(short as effective SWH),and the total potential of wave energy is exploratively calculated.Synthetically considering a wave energy density,a wave energy level probability,the frequency of the effective SWH,the stability and long-term trend of wave energy density,a swell index and a wave energy storage,global ocean wave energy resources were reanalyzed and regionalized,providing reference to the development of wave energy resources such as wave power plant location,seawater desalination,heating,pumping. 展开更多
关键词 global ocean wave energy resources effective significant wave height wave energy storage grade division
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Management of small hepatocellular carcinoma in cirrhosis:Focus on portal hypertension 被引量:20
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作者 Virginia Hernandez-Gea Fanny Turon +1 位作者 Annalisa Berzigotti Augusto Villanueva 《World Journal of Gastroenterology》 SCIE CAS 2013年第8期1193-1199,共7页
The incidence of hepatocellular carcinoma(HCC) is rising worldwide being currently the fifth most common cancer and third cause of cancer-related mortality.Early detection of HCC through surveillance programs have ena... The incidence of hepatocellular carcinoma(HCC) is rising worldwide being currently the fifth most common cancer and third cause of cancer-related mortality.Early detection of HCC through surveillance programs have enabled the identification of small nodules with higher frequency,and nowadays account for 10%-15% of patients diagnosed in the West and almost 30% in Japan.Patients with small HCC can be candidates for potential curative treatments:liver transplantation,surgical resection and percutaneous ablation,depending on the presence of portal hypertension and co-morbidities.This review will analyze recent advancements in the clinical management of these individuals,focusing on issues related to the role of portal hypertension,the debate between resection and ablative therapies and the future impact of molecular technologies. 展开更多
关键词 PORTAL HYPERTENSION Hepatic VENOUS pressure gradient Clinically significant PORTAL HYPERTENSION LIVER stiffness LIVER cancer Hepatocellular carcinoma Resection RADIOFREQUENCY ablation PERCUTANEOUS ethanol injection
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Recent Significant Tornadoes in China 被引量:19
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作者 Ming XUE Kun ZHAO +2 位作者 Mingjung WANG Zhaohui LI Yongguang ZHENG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2016年第11期1209-1217,共9页
1.Introduction Compared with the United States,whose annual number of tornadoes can exceed 1000,the average number of tornadoes per year in China over the past half a century is estimated to be fewer than 100(Fan and... 1.Introduction Compared with the United States,whose annual number of tornadoes can exceed 1000,the average number of tornadoes per year in China over the past half a century is estimated to be fewer than 100(Fan and Yu,2015),even though both countries are located in a similar latitudinal zone of the Northern Hemisphere. 展开更多
关键词 LST Recent significant Tornadoes in China
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耳穴及生活方式预防2型糖尿病的随机对照试验研究 被引量:18
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作者 陈琳 张伯宇 《世界中医药》 CAS 2019年第3期750-753,共4页
目的:探讨耳穴及生活方式对2型糖尿病前期人群的预防效果。方法:选取2017年5月至2018年3月在顺义区中医院接受体检的2型糖尿病前期人群92例进行观察,按照随机数表法分为对照组和观察组,每组46例,对照组给予常规干预,观察组在对照组的基... 目的:探讨耳穴及生活方式对2型糖尿病前期人群的预防效果。方法:选取2017年5月至2018年3月在顺义区中医院接受体检的2型糖尿病前期人群92例进行观察,按照随机数表法分为对照组和观察组,每组46例,对照组给予常规干预,观察组在对照组的基础上给予耳穴压豆干预治疗。比较2组2型糖尿病前期人群干预前后的糖化血红蛋白(Hb A1c)、体质量指数(BMI)、空腹血糖(FPG)、餐后2 h血糖(P2 h PG)、收缩压(SBP)、舒张压(DBP)、总胆固醇(TC)、三酰甘油(TG)、高密度脂蛋白(HDL)及低密度脂蛋白(LDL)变化情况,以及干预1年后糖尿病转归情况。结果:与干预前比较,对照组仅FPG与P2 h PG较干预前均显著降低,观察组FPG、P2 h PG、TC、HDL及Hb A1c较干预前显著降低,而LDL显著升高,差异均有统计学意义(P <0. 05);干预后2组比较,观察组FPG、P2 h PG、TC、LDL及Hb A1c降低更显著,而LDL升高更显著,差异有统计学意义(P <0. 05);干预后观察组糖尿病转化率2. 17%(1/46),对照组糖尿病转化率13. 04%(6/46),差异有统计学意义(P <0. 05)。结论:耳穴压豆联合生活方式干预可更有效地改善2型糖尿病期人群的血糖及血脂水平,有效降低。 展开更多
关键词 耳穴 生活方式 干预 2型糖尿病 前期人群 血糖 血脂 糖尿病转化率
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最密切联系原则对传统冲突规范的突破及“硬化”处理 被引量:15
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作者 肖永平 任明艳 《河南司法警官职业学院学报》 2003年第3期15-20,共6页
最密切联系原则是当代国际私法发展中出现的一种以实用主义的经验方法进行法律选择的学说。20世纪中叶特别是70年代以来已经引起国际私法学界的高度重视。这一原则对国际私法的立法和实践有着重要的影响。本文拟就最密切联系原则的历史... 最密切联系原则是当代国际私法发展中出现的一种以实用主义的经验方法进行法律选择的学说。20世纪中叶特别是70年代以来已经引起国际私法学界的高度重视。这一原则对国际私法的立法和实践有着重要的影响。本文拟就最密切联系原则的历史沿革、具体运用、对传统法律选择方法的突破及追求目标、硬化处理等几个方面作初步的研究。 展开更多
关键词 最密切联系原则 突破 灵活性 确定性 硬化
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无线多媒体传感器网络中一种自适应的报头压缩机制 被引量:14
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作者 周新运 孙利民 +1 位作者 皇甫伟 牛建伟 《软件学报》 EI CSCD 北大核心 2007年第5期1122-1129,共8页
无线多媒体传感器网络传输大数据量的音频、视频、图像等数据,需要高效地利用宝贵的无线信道资源.报头压缩技术能够减小传输的数据量,提高信道利用效率.提出一种自适应的报头压缩机制AAHC,基于对信道状态的准确估计,动态调整压缩算法的... 无线多媒体传感器网络传输大数据量的音频、视频、图像等数据,需要高效地利用宝贵的无线信道资源.报头压缩技术能够减小传输的数据量,提高信道利用效率.提出一种自适应的报头压缩机制AAHC,基于对信道状态的准确估计,动态调整压缩算法的参数,并使用UDP(user datagram protocol)Lite协议作为传输层协议.AAHC机制在获得较高压缩效率的同时,可保证报头压缩的抗差错鲁棒性.仿真结果表明,AAHC机制的性能优于传统的ROHC(robust header compression)机制和CRTP(compressed RTP)机制. 展开更多
关键词 无线多媒体传感器网络 报头压缩 W-LSB(window-based least significant bits)编码 UDP(user DATAGRAM protocol)Lite
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地质样品Sr同位素激光原位等离子体质谱(LA-MC-ICP-MS)测定 被引量:16
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作者 杨岳衡 吴福元 +2 位作者 谢烈文 杨进辉 张艳斌 《岩石学报》 SCIE EI CAS CSCD 北大核心 2009年第12期3431-3441,共11页
Sr同位素在研究岩浆演化及其源区具有重要的示踪作用。MC-ICP-MS的出现为具有高Sr含量地质样品的激光原位Sr同位素测定变成了现实。本文利用Netpune MC-ICP-MS和193nm准分子激光联机,通过滨珊瑚、斜长石、磷灰石和钙钛矿等系列实验,建... Sr同位素在研究岩浆演化及其源区具有重要的示踪作用。MC-ICP-MS的出现为具有高Sr含量地质样品的激光原位Sr同位素测定变成了现实。本文利用Netpune MC-ICP-MS和193nm准分子激光联机,通过滨珊瑚、斜长石、磷灰石和钙钛矿等系列实验,建立了激光原位Sr同位素测定方法。实验结果表明,激光Sr同位素测定中Kr、Rb和稀土元素二价离子的干扰能够有效扣除,而钙聚合物的干扰在Neptune型MC-ICP-MS并不显著。不同激光参数的实验表明,大激光束斑产生更高信号强度,因而Sr同位素精度更高,同一激光束斑大小,激光脉冲频率对Sr同位素精度无明显影响。 展开更多
关键词 地质样品 同位素测定 激光原位 等离子体质谱 natural isotopic measurement inductively coupled plasma analytical procedure spatial resolution mass spectrometry analysis in-situ PORITES coral excimer laser 实验 激光束 significant development 准分子激光 spot size
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中西方传统建筑:一种符号学视角的观察 被引量:12
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作者 王贵祥 《建筑师》 2005年第4期32-39,共8页
本文从西方20世纪流行的符号学概念,特别是符号的“能指”与“所指”概念出发,在对符号学一般性定义进行分析的基础上,将中西方建筑思想中一些基本观点纳入其中进行比较分析,从而发现中西传统建筑在基本出发点上的一些差异。西方古典建... 本文从西方20世纪流行的符号学概念,特别是符号的“能指”与“所指”概念出发,在对符号学一般性定义进行分析的基础上,将中西方建筑思想中一些基本观点纳入其中进行比较分析,从而发现中西传统建筑在基本出发点上的一些差异。西方古典建筑将“美观”作为基本目标,并将着眼点落在建筑之形式及形式美的艺术性探索上,而中国传统建筑将具有实用性质的“空间”及具有“意义”内涵的礼制规则作为基本目标,从而将建筑的着眼点落在建筑之空间、体量与装饰的等级差别(度)上。这一基本分析,标识了中西传统建筑的一个基本差异。 展开更多
关键词 传统建筑 建筑风格 建筑文化 建筑形式
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Effects of urbanization on daily temperature extremes in North China 被引量:14
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作者 SI Pengt ZHENG Zuofang +3 位作者 REN Yu LIANG Dongpo LI Mingcai SHU Wenjun 《Journal of Geographical Sciences》 SCIE CSCD 2014年第2期349-362,共14页
The regional changes of daily temperature extremes in North China caused by ur- banization are studied further from observed facts and model estimates on the basis of ho- mogenized daily series of maximum and minimum ... The regional changes of daily temperature extremes in North China caused by ur- banization are studied further from observed facts and model estimates on the basis of ho- mogenized daily series of maximum and minimum temperature observations from 268 mete- orological stations, NCEP/DOE AMIP- Ⅱ reanalysis data (R-2), and the data of simulations by regional climate model (RegCM3). The observed facts of regional warming on long time scales are obtained by analyzing the indices of temperature extremes during two time periods of 1961-2010 and 1951-2010. For urbanization effect, the contributions to decreases in an- nual and winter diurnal temperature range (DTR) are 56.0% and 52.9%, respectively, and increases in the lowest minimum temperature (TNn) are 35.7% and 26.2% by comparison of urban and rural observations. Obtained by R-2 data with observations for contrast, on the other hand, increase in the number of annual warm nights (TN90p) contributed by urbaniza- tion is 60.9%. And observed facts of regional warming in daily temperature extremes are also reflected in the simulations, but what difference is urbanization progress at rural areas in North China would be prominent in the next few years relative to urban areas to some extent from model estimates. 展开更多
关键词 URBANIZATION daily temperature extremes significant contribution North China
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Effect Research of Immobilized Algae-bacteria Removal Ammonia Nitrogen of Aquaculture Wastewater and Proposed Model 被引量:14
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作者 邹万生 张景来 +1 位作者 刘良国 邓武军 《Agricultural Science & Technology》 CAS 2010年第5期117-120,共4页
Applied Immobilized algae bacteria (ABI) to remove ammonia of freshwater aquaculture wastewater. Temperature (T),PH,light intensity (I),dissolved oxygen (DO) and filling rate five factors plays important role in the p... Applied Immobilized algae bacteria (ABI) to remove ammonia of freshwater aquaculture wastewater. Temperature (T),PH,light intensity (I),dissolved oxygen (DO) and filling rate five factors plays important role in the process of ammonia nitrogen removal ,related data between ammonia removal and five factors was received through multi-factor orthogonal test,and established relations model between the five factor and nitrogen removal. The results show that five-factors had significant effect on AR,and the best combinations for removing AR was temperature 30 ℃,pH=7.0,light intensity 6 000 lux,dissolved oxygen 5.0 mg/L and the fill rate 10%. According to the experimental data,equation model was proposed and coefficient of determination R2 =0.864 8,P<0.05. Samples T-test was done between the model predictions and the actual measured values.Test results showed that the significant difference of overall mean value sig. (2-tailed) was 0.978 (P>0.05),it Shows that had no significant difference between model predictions and the actual measured value,and model had a high degree of fitting. 展开更多
关键词 Immobilized Algae-bacteria Aquaculture wastewater Ammonia remove rate Proposed model
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NUMERICAL SIMULATION OF SEA SURFACE DIRECTIONAL WAVE SPECTRA UNDER TYPHOON WIND FORCING 被引量:12
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作者 ZHOU Liang-ming WANG Ai-fang GUO Pei-fang 《Journal of Hydrodynamics》 SCIE EI CSCD 2008年第6期776-783,共8页
Numercial simulation of sea surface directional wave spectra under typhoon wind forcing in the South China Sea (SCS) was carreid out using the WAVEWATCH-Ⅲ wave model. The simulation was run for 210 h until the Typh... Numercial simulation of sea surface directional wave spectra under typhoon wind forcing in the South China Sea (SCS) was carreid out using the WAVEWATCH-Ⅲ wave model. The simulation was run for 210 h until the Typhoon Damrey (2005) approached Vietnam. The simulated data were compared with buoy observations, which were obtained in the northwest sea area of Hainan Island. The results show that the significant wave height, wave direction, wave length and frequency spetra agree well with buoy observations. The spatial characteristics of the signifciant wave height, mean wave period, mean wave length, wave age and directional spectra depend on the relative position from the typhoon center. Also, the misalignment between local wind and wave directions were investigated. 展开更多
关键词 TYPHOON directional spectra significant wave height South China Sea (SCS)
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Simulation of Typhoon-Driven Waves in the Yangtze Estuary with Multiple-Nested Wave Models 被引量:12
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作者 徐福敏 Will Perrie +2 位作者 张君伦 宋志尧 Bechara Toulany 《China Ocean Engineering》 SCIE EI 2005年第4期613-624,共12页
Typhoon-generated waves are simulated with two numerical wave models, the SWAN model for the coastal and Yangtze Estuary domain, nested within the WAVEWATCHIII (WW3) for the basin-scale East China Sea domain. Typhoo... Typhoon-generated waves are simulated with two numerical wave models, the SWAN model for the coastal and Yangtze Estuary domain, nested within the WAVEWATCHIII (WW3) for the basin-scale East China Sea domain. Typhoon No. 8114 is chosen because it was very strong, and generated high waves in the Estuary. WW3 was implemented for the East China Sea coarse-resolution computational domain, to simulate the waves over a large spatial scale and provide boundary conditions for SWAN model simulations, implemented on a fine-resolution nested domain for the Yangtze Estuary area. The Takahashi wind model is applied to the simulation of the East China Sea scale (3-hourly) and Yangtze Estuary scale (1-hourly) winds. Simulations of significant wave heights in the East China Sea show that the highest waves are on the right side of the storm track, and maxima tend to occur at the eastern deep-water open boundary of the Yangtze Estuary. In the Yangtze Estuary, incoming swell is dominant over locally generated waves before the typhoon approaches the Estuary. As the typhoon approaches the Estuary, wind waves and swell coexist, and the wave direction is mainly influenced by the swell direction and the complex topography. 展开更多
关键词 WW3 SWAN typhoon-generated waves East China Sea Yangtze Estuary Takahashi wind model 2 D wave spectra significant wave height
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南海盆海山火山碎屑岩的发现及其地质意义 被引量:12
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作者 鄢全树 石学法 《岩石学报》 SCIE EI CAS CSCD 北大核心 2009年第12期3327-3334,共8页
海山火山碎屑岩是水下爆发性火山作用的产物。南海盆两座海山上发现火山碎屑岩表明海山顶部曾经一度高于PCL(压力补偿深度)。岩相学特征显示这些火山碎屑岩的胶结物主要为一混合相,包括粘土矿物和黑色铁质矿物等,这从一个侧面反映海山... 海山火山碎屑岩是水下爆发性火山作用的产物。南海盆两座海山上发现火山碎屑岩表明海山顶部曾经一度高于PCL(压力补偿深度)。岩相学特征显示这些火山碎屑岩的胶结物主要为一混合相,包括粘土矿物和黑色铁质矿物等,这从一个侧面反映海山的正地形限制了粗粒外生碎屑到达海山顶部。岩石的单矿物组分、主量元素化学特征与同海山玄武质熔岩具有可比性,属碱性岩浆系列。计算获得海山平均最小下沉速率为0.06mm/年,最大可能达0.30mm/年。海山岩石的机械风化产物对周围海盆的沉积作用作出重要贡献。 展开更多
关键词 海盆 海山 火山碎屑岩 地质意义 implications the South China Sea major element pressure compensation clay minerals 粘土矿物 significant 岩相学特征 主量元素 岩石 矿物组分 碱性岩浆 火山作用 化学特征 风化产物 沉积作用
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商品化权初探 被引量:6
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作者 陈军 《渝州大学学报(社会科学版)》 2002年第2期53-56,共4页
“商品化权”概念的性质是商誉。商品化权克服了著作权、商标权、反不正当竞争权的缺陷 ,因而具有存在价值。商品化权冲击了狭义的知识产权体系 ,属于广义的知识产权的一部分 ,并与其他知识产权发生权利冲突。
关键词 商品化权 商誉 存在价值 知识产权 权利冲突
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内蒙古镶黄旗地区牛寄生虫病调查报告 被引量:11
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作者 陈少博 布和巴特尔 +1 位作者 其其格 哈斯苏荣 《中国牛业科学》 2012年第6期77-80,共4页
[目的]为了解半舍饲与半放牧条件下牛胃肠道寄生虫病的流行情况,于2011年5月到2012年5月间,较为系统地调查了锡林郭勒盟镶黄旗地区三个不同苏木、镇的牛寄生虫病流行情况。[方法]首先针对不同草场、舍饲与半舍饲条件的牛群,先后共采集了... [目的]为了解半舍饲与半放牧条件下牛胃肠道寄生虫病的流行情况,于2011年5月到2012年5月间,较为系统地调查了锡林郭勒盟镶黄旗地区三个不同苏木、镇的牛寄生虫病流行情况。[方法]首先针对不同草场、舍饲与半舍饲条件的牛群,先后共采集了708个粪样。然后借助饱和盐水漂浮法、离心沉淀法和麦克马斯特氏虫卵计数的方法,对粪便样品虫卵进行定性和定量检查。[结果]表明,该地区牛群胃肠道寄生虫总感染率为44.92%。根据虫卵形态特征初步鉴定出9种虫卵,分别隶属于3门3纲3目5科和9属,未检查到吸虫。比较分析了不同地区和不同草场类型牛群的胃肠道寄生虫感染情况。[结论]不同草场类型的牛胃肠道寄生虫感染率有显著性差异(P<0.01)。 展开更多
关键词 牛寄生虫 流行病学 内蒙古 差异
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冷却速率对Mg-Gd-Y-Zr合金凝固组织的影响(英文) 被引量:11
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作者 周吉学 杨院生 +3 位作者 童文辉 王杰 付俊伟 汪彬 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2010年第11期1899-1902,共4页
通过改变凝固过程中的冷却速率,研究了冷却速率对Mg-Gd-Y-Zr合金凝固组织与成分微观偏析的影响。随冷却速率提高,合金组织明显细化,初生相形貌由粗大等轴枝晶逐渐向细小树枝晶转变,合金凝固过程中形核率增加,合金晶粒尺寸逐渐减小;冷却... 通过改变凝固过程中的冷却速率,研究了冷却速率对Mg-Gd-Y-Zr合金凝固组织与成分微观偏析的影响。随冷却速率提高,合金组织明显细化,初生相形貌由粗大等轴枝晶逐渐向细小树枝晶转变,合金凝固过程中形核率增加,合金晶粒尺寸逐渐减小;冷却速率的提高可以降低溶质元素的扩散速率,从而增加合金元素在枝晶干中的固溶度,减轻凝固过程中合金元素Gd与Y的微观偏析,同时使凝固过程中形成的共晶减少,共晶组织分布更加弥散、均匀。 展开更多
关键词 冷却速率 合金凝固组织 MICROSTRUCTURE cooling rate 合金凝固过程 MICROSTRUCTURE 微观偏析 合金元素 solid solubility volume fraction 等轴枝晶 significant 组织分布 溶质元素 扩散速率 晶粒尺寸 合金组织 共晶 形核率 相形貌
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中国省域建筑业发展差异的空间计量经济分析 被引量:10
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作者 张峁 乔东艳 戴永安 《科学决策》 2010年第3期87-93,共7页
基于2005年~2007年我国31个省(直辖市)建筑业的面板数据,利用空间经济计量方法对其进行了系统的分析,揭示了我国省域建筑业之间的强空间相关性和空间异质性,分析结果表明:为了更加深入地理解我国建筑业对经济增长的影响,必须强调地域... 基于2005年~2007年我国31个省(直辖市)建筑业的面板数据,利用空间经济计量方法对其进行了系统的分析,揭示了我国省域建筑业之间的强空间相关性和空间异质性,分析结果表明:为了更加深入地理解我国建筑业对经济增长的影响,必须强调地域空间因素的重要性,这样既有助于明确建筑业对经济增长的空间影响,同时也为国家协调区域经济发展、制定相应的区域发展政策提供相应理论依据。 展开更多
关键词 空间计量经济学 空间积聚 建筑业 显著
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Validation of Chinese HY-2 satellite radar altimeter significant wave height 被引量:10
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作者 YE Xiaomin LIN Mingsen XU Ying 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第5期60-67,共8页
Chinese Haiyang-2(HY-2) satellite is the first Chinese marine dynamic environment satellite. The dual-frequency (Ku and C band) radar altimeter onboard HY-2 has been working effective to provide operational signif... Chinese Haiyang-2(HY-2) satellite is the first Chinese marine dynamic environment satellite. The dual-frequency (Ku and C band) radar altimeter onboard HY-2 has been working effective to provide operational significant wave height (SWH) for more than three years (October 1, 2011 to present).We validated along-track Ku-band SWH data of HY-2 satellite against National Data Buoy Center (NDBC) in-situ measurements over a time period of three years from October 1, 2011 to September 30, 2014, the root mean square error (RMSE) and mean bias of HY-2 SWH is 0.38 m and (-0.13±0.35) m, respectively. We also did cross validation against Jason-2 altimeter SWH data, the RMSE and the mean bias is 0.36m and (-0.22±0.28) m, respectively. In order to compare the statistical results between HY-2 and Jason-2 satellite SWH data, we validated the Jason-2 satellite radar altimeter along-track Ku-band SWH data against NDBC measurements using the same method. The results demonstrate the validation method in this study is scientific and the RMSE and mean bias of Jason-2 SWH data is 0.26 m and (0.00±0.26) m, respectively. We also validated both HY-2 and Jason-2 SWH data every month, the mean bias of Jason-2 SWH data almost equaled to zero all the time, while the mean bias of HY-2 SWH data was no less than -0.31m before April 2013 and dropped to zero after that time. These results indicate that the statistical results for HY-2 altimeter SWH are reliable and HY-2 altimeter along-track SWH data were steady and of high quality in the last three years. The results also indicate that HY-2 SWH data have greatly been improved and have the same accuracy with Jason-2 SWH data after April, 2013. SWH data provided by HY-2 satellite radar altimeter are useful and acceptable for ocean operational applications. 展开更多
关键词 significant wave height VALIDATION Chinese HY-2 satellite radar altimeter
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Estimating significant wave height from SAR imagery based on an SVM regression model 被引量:9
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作者 GAO Dong LIU Yongxin +2 位作者 MENG Junmin JIA Yongjun FAN Chenqing 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2018年第3期103-110,共8页
A new method for estimating significant wave height(SWH) from advanced synthetic aperture radar(ASAR) wave mode data based on a support vector machine(SVM) regression model is presented. The model is established... A new method for estimating significant wave height(SWH) from advanced synthetic aperture radar(ASAR) wave mode data based on a support vector machine(SVM) regression model is presented. The model is established based on a nonlinear relationship between σ0, the variance of the normalized SAR image, SAR image spectrum spectral decomposition parameters and ocean wave SWH. The feature parameters of the SAR images are the input parameters of the SVM regression model, and the SWH provided by the European Centre for Medium-range Weather Forecasts(ECMWF) is the output parameter. On the basis of ASAR matching data set, a particle swarm optimization(PSO) algorithm is used to optimize the input kernel parameters of the SVM regression model and to establish the SVM model. The SWH estimation results yielded by this model are compared with the ECMWF reanalysis data and the buoy data. The RMSE values of the SWH are 0.34 and 0.48 m, and the correlation coefficient is 0.94 and 0.81, respectively. The results show that the SVM regression model is an effective method for estimating the SWH from the SAR data. The advantage of this model is that SAR data may serve as an independent data source for retrieving the SWH, which can avoid the complicated solution process associated with wave spectra. 展开更多
关键词 advanced synthetic aperture radar wave mode support vector machine significant wave height
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