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三峡大学学报（自然科学版） 2005年第3期27卷 197-200页

作者：王斌向学军王颢雄 Luk PcK 三峡大学电气信息学院湖北宜昌443002 克兰菲尔德大学航空动力与传感器系谢尔文翰英国750111

提供了一种新的双随机脉冲调制技术,它能够很好地减小电力电子系统中存在的传导电磁干扰,这个调制技术是通过同时改变开关频率和脉冲的上升沿位置来实现的。与已经存在的任何一种单随机方案相比,双随机调制技术驱散谐波能量而使之具有... 详细信息

提供了一种新的双随机脉冲调制技术,它能够很好地减小电力电子系统中存在的传导电磁干扰,这个调制技术是通过同时改变开关频率和脉冲的上升沿位置来实现的。与已经存在的任何一种单随机方案相比,双随机调制技术驱散谐波能量而使之具有更宽的带宽,能更加有效地减少功率变换器系统的离散谱峰值。给出了基于三菱数字信号处理器实现双随机PWM调制信号的技术及其实验结果。

关键词：双随机脉冲调制技术 DSP 电力电子系统传导电磁调制技术开关频率脉冲信号处理器

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Spastin突变所致遗传性痉挛性截瘫的临床特征

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世界核心医学期刊文摘(神经病学分册) 2006年第12期 11-11页

作者： Mc Dermott c.J. Burness c.E. Kirby J. P.J.Shaw 郭俊 Dr.Academic Neurology Unit Sheffield UniversitySheffieldUnited Kingdom

BAcKgROUND:Mutations in the spastin gene are the commonest cause of hereditary spastic paraparesis(HSP),accounting for up to 40%of autosomal dominant *** phenotype associated with HSP due to mutation in the spastin gene(SPg4)tends to be pure ***:To characterize in more detail the genetic and phenotypic characteristics of SPg4 by examining a large cohort of patients with ***:The authors identified patients who tested positive for spastin mutation using a direct sequencing approach of all ***:The authors identified spastin mutations in 53 ***-seven of the mutations identified were *** phenotype in the majority of patients was of pure *** one individual,a complicated phenotype with progressive bulbar dysfunction and respiratory insufficiency was *** of lower motor neuron dysfunction in a subgroup of SPg4 patients was *** missense changes S44L and P45q were identified in patients with other spastin mutations and seemed to be exerting a phenotype-modifying ***:These findings add to the number of spastin mutations identified and demonstrate the importance of screening the whole gene,given the possibility of double mutations and intragenic *** identification of the complicated phenotypes has important implications for identifying the phenotype of patients in whom spastin screening should be *** presence of lower motor neuron dysfunction in a subgroup of SPg4 patients suggests that the cellular dysfunction in SPg4 extends beyond the axonal projections of upper motor neurons and ascending sensory pathways.

关键词：基因筛查运动神经元传出神经元 Spastin 功能障碍

Study of penetration and diffusion for 2011 Japan-Fukushima nuclear plant leak problem

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Study of penetration and diffusion for 2011 Japan-Fukushima ...

中国地球物理学会第二十七届年会

作者： H H cheng~1 c.L.Liu~(1,2) B.J.Zhu~1 Y.L.Shi~1 1.Key Laboratory of computational geodynamics of chinese Academy of Sciences college of Earth Science, graduate University of chinese Academy of Sciences,Beijing 100049 P.R.china 2.Laboratoire De geologie,Ecole Normale Superieure,24 Rue Lhomond,75231 Paris cEDEX 5,France

＜正＞Based on the hybrid hypersingular integral equation-Lattice Boltzmann method（HHIE-LBM）,the typicalextended 3D flow driven pore-crack network Fukushima Nuclear plant leak accident model is established and thepenetration and diffusion process of cesium-137 at different temporal spatial scales have been *** shownin Figure.1 the multi temporal spatial scale Fukushima cesium-137 penetration and diffusion D3q27 LBM modelis *** analyze the problem at different scale,four kind of scales[scaleⅠ（E140.25°～141.021°;N37°～39°）,scaleⅡ（E139.4°～142.4°;N35.8°～38.8°）,scaleⅢ（E140.15°-141.65°;N36.55°～38°） and scaleⅣ（E140.4°～141.4°;N36.8°～37.8°）]penetration and diffusion model are defined in our simulation *** penetration and

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ИЭМАИЛЬСКИЙ生色理論的初步研究

南京大学学报(自然科学版) 1957年第2期 85-91页

作者：朱永蔡士德路澄華南京大学化学系有机化学教研组

有色化合物中,包括下列一种結構类型的化合物:其中B为吸电子基团,如—NO2,>c=O…等;K为共軛体系,如—c6H4—等;q为連接二个共軛体系的基团,可以是使BK与AK共軛的—cH=N—,—N=N—也可以是不使BK与AK共軛的—cONH—,—cH2—NH—,—cH2cON... 详细信息

有色化合物中,包括下列一种結構类型的化合物:其中B为吸电子基团,如—NO2,>c=O…等;K为共軛体系,如—c6H4—等;q为連接二个共軛体系的基团,可以是使BK与AK共軛的—cH=N—,—N=N—也可以是不使BK与AK共軛的—cONH—,—cH2—NH—,—cH2cONH—…等;A为給电子基团,如—OcH3,—NH2等。發現当q为—cONH—,

关键词：甲氧基苯甲酸 AK 基团电子蚁酸饱和脂肪酸轻子乙醇酒精熔点熔解温度深黄色三甲氧基苯胺南京大学学报未知物上加热化合物 NH OcH 甲醚共扼

Research on the proper selection of soil constitutive relation in modeling underground excavation

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Research on the proper selection of soil constitutive relati...

第五届国际材料与热加工物理模拟及数值模拟学术会议

作者： Yin-tao ZHANg1 a Lian-jin TAO1 b Si-hai TANg1 c Bin SUN1 d 1 Beijing University of Technology Beijing china

Soil is a complex material whose properties are elastic, plastic and viscious. The selection of a proper constitutive relation is important in the study of stratum movement induced by underground excavation in modern cities. First, based on the Fast Lagrangian Analysis of continua （FLAc） method, the elastic response stress （p, q） distribution induced by a circular tunnel is analyzed, and the surrounding soil is divided into four categories: p increase q increase, p increase q decrease, p decrease q increase, p decrease q decrease according to p-q stress path. The character of p-q distribution and the plastic zone induced by tunneling in clay are compared when the Mohr-coulomb model （M-c）, the Drucker-Prager model （D-P） and the Modified cam-clay model （c-c） are adopted;the c-c model is considered to be suitable for simulating underground excavation problems. Second, factors such as stratum character, stress path and relative position between soil and excavation are thought to be important in the selection of a proper constitutive relation, accounting for the geological condition of Beijing and measuring techniques being used in geotechnical engineering. Fine grained soils such as clay and silt can be modeled by the c-c model. coarse grained soil, for containing and not containing excavation, may be represented using the M-c model considering strain softening and the normal M-c model. Finally, with the aid of FLAc method and its internal language FISH, a scheme of estimating and controlling parameter input is suggested.

关键词： Underground excavation constitutive relation Stress path P-q distribution

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提升设备的能力及其影响因素

采矿技术 1985年第5期 26-26页

作者： c.M.库巴列夫肖通遥 [苏联]斯维尔德洛夫斯克矿业学院技术科学副博士

提升设备的年生产能力由下式计算:式中:N—提升设备一年的工作天数;T—一昼夜的工作时数,小时;q—提升负荷,吨;c—提升生产能力备用系数;H—提升高度,米;Vm—最大提升速度,米/秒;V_o—箕斗进入和退出卸载弯轨的速度,米/秒;

关键词：提升设备提升速度提升量生产能力

基因突变致β细胞KATP通道超敏感性可致新生鼠严重糖尿病

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国际内分泌代谢杂志 2001年第3期21卷 164-164页

作者：杨菊红徐隆绍 Koster J c

β细胞中葡萄糖升高致ATP/ADP比值升高，从而关闭K通道导致细胞去极化，ca2＋内流使胰岛素分泌而降低血糖。因而人们推测基因突变致β细胞中KATP通道对ATP/ADP升高的敏感性降低,继而胰岛素分泌不足而致糖尿病。方法与设计构建突变KATP... 详细信息

β细胞中葡萄糖升高致ATP/ADP比值升高，从而关闭K通道导致细胞去极化，ca2＋内流使胰岛素分泌而降低血糖。因而人们推测基因突变致β细胞中KATP通道对ATP/ADP升高的敏感性降低,继而胰岛素分泌不足而致糖尿病。方法与设计构建突变KATP基因质粒重组子，分别为Kir 6.2亚单位N端2-30缺失(Kir 6.2［△N2-30］)及Kir 6.2亚单位N端2-30缺失合并185点突变(Kir 6.2［△N2-30，K185q］)。将两种突变基因于c端与绿荧光蛋白(gTP)融合(以利于检测)，使其与KATP磺脲类受体1亚单位DNA共同表达形成功能性KATP。将构建质粒注入c57B16*cBA鼠卵中，使其在胰岛素启动子1控制下于胰岛β细胞中表达。培养基因突变小鼠。结果在60只新生鼠中未检测到1只携有Kir 6.2［△N2-30，K185q］基因，而检测到5只携带Kir 6.2［△N2-30］基因。将这5只鼠与cD-1系鼠繁殖建立5种转基因鼠系。结果5种鼠系中有4系原代鼠均血糖正常且发育正常，而其所有F1代鼠均有严重高血糖、低胰岛素血症、血D-3-羟丁酸水平显著升高，且大多于5 d内死亡，或者体重显著降低而需胰岛素维持。另外1系F1代小鼠同样携带Kir 6.2［△N2-30］基因，但研究发现其胰岛中受累β细胞非常少，因而其血糖正常。同时，研究还发现所有小鼠胰岛的形态、胰岛素的定位，β细胞的分布均正常。结论研究证实KATP通道的高敏感性，也即对ATP/ADP升高的反应性降低可以抑制胰岛素的分泌，导致严重糖尿病发生。

关键词： β细胞 KATP 糖尿病代谢病基因突变点突变新生鼠

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纳帕海湿地

全球变化数据学报（中英文） 2017年第3期1卷 369-369,369页

作者：李杰胡金明刘闯石瑞香云南财经大学城市与环境学院昆明650021 云南大学云南省国际河流与跨境生态安全重点实验室昆明650091 中国科学院地理科学与资源研究所北京100101

纳帕海湿地位于青藏高原东南延伸的横断山脉,云南省迪庆藏族自治州香格里拉县境内,长江上游支流金沙江流域内。地理位置位于27°48′36″N-27°54′27″N,99°37′12″E-99°40′30″E。纳帕海湿地于2005年被批准纳入到国际重要湿地名录... 详细信息

纳帕海湿地位于青藏高原东南延伸的横断山脉,云南省迪庆藏族自治州香格里拉县境内,长江上游支流金沙江流域内。地理位置位于27°48′36″N-27°54′27″N,99°37′12″E-99°40′30″E。纳帕海湿地于2005年被批准纳入到国际重要湿地名录,编号为1440。纳帕海湿地南北长11.38 km,东西宽4.5 km。地势北高南低,海拔高度由北向南由3,285 m降至3,275m,地势比降0.88‰。

关键词：纳帕海湿地国际重要湿地名录界线横断山脉数据大百科

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Time Series Analysis on Selected Rainfall Stations Data in Louisiana Using ARIMA Approach

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Open Journal of Statistics 2021年第5期11卷 655-672页

作者： Yaw A. Twumasi Jacob B. Annan Edmund c. Merem John B. Namwamba Tomas Ayala-Silva Zhu H. Ning Abena B. Asare-Ansah Judith Oppong Diana B. Frimpong Priscilla M. Loh Faustina Owusu Lucinda A. Kangwana Olipa S. Mwakimi Brilliant M. Petja Ronald Okwemba caroline O. Akinrinwoye Hermeshia J. Mosby Joyce Mcclendon-Peralta Department of Urban Forestry and Natural Resources Southern University and A&M College Baton Rouge Louisiana USA Department of Urban and Regional Planning Jackson State University Jackson Mississippi USA USDA-ARS Tropical Agriculture Research Station Mayaguez Puerto Rico USA Institute of Resource Assessment University of Dares Salam Dares Salam Tanzania Water Research commission (WRc) Private Bag X03 Gezina South Africa

Precipitation is very important for both the environment and its inhabitants. Agricultural activities mostly depend on precipitation and its availability. Therefore, the ability to predict future precipitation values at specific stations is key for environmental and agricultural decision making. This research developed Autoregressive Integrated Moving Average (ARIMA) models for selected stations with Integrated component and Autoregressive Moving Average (ARMA) for selected stations without Integrated component at Louisiana State. The ARIMA module is represented as ARIMA(p, d, q)(P,D,q). The selected lag order for the Autoregressive (AR) component is represented with p and P for seasonal AR component, while the integrated form (number of times data were differenced) is d and D for seasonal differencing, and the Moving Average (MA) lag order is q and q for seasonal MA component. Data from 1950 to 2020 were employed in this research. Results of the analysis indicated that Baton Rouge (ARIMA (0,1,1) (0,0,2)12), Abbeville (ARMA (0,0,1) (0,0,2)12), Monroe Regional (ARMA (0,0,1) (0,0,0)12), New Orleans Airport (ARMA (1,0,0) (0,0,2)12), Alexandria (ARMA (1,0,1) (0,0,0)12), Logansport (ARIMA (0,1,2) (0,0,0)12), New Orleans Audubon (ARMA (1,0,0) (0,0,0)12), Lake Charles Airport (ARMA (2,0,2) (0,0,0)

关键词： Precipitation ARIMA Models Time Series Lowess Louisiana