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The effect of polymer type on electric breakdown strength on a nanosecond time scale 被引量:1
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作者 赵亮 苏建仓 +1 位作者 潘亚峰 张喜波 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第3期158-163,共6页
Based on the concepts of fast polarization, effective electric field and electron impact ionization criterion, the effect of polymer type on electric breakdown strength (EBD) on a nanosecond time scale is investigat... Based on the concepts of fast polarization, effective electric field and electron impact ionization criterion, the effect of polymer type on electric breakdown strength (EBD) on a nanosecond time scale is investigated, and a formula that qualitatively characterizes the relation between the electric breakdown strength and the polymer type is derived. According to this formula, it is found that the electric breakdown strength decreases with an increase in the effective relative dielectric constants of the polymers. By calculating the effective relative dielectric constants for different types of polymers, the theoretical relation for the electric breakdown strengths of common polymers is predicted. To verify the prediction, the polymers of PE (polyethylene), PTFE (polytetrafluoroethelene), PMMA (organic glass) and Nylon are tested with a nanosecond-pulse generator. The experimental result shows EBD (PTFE) 〉 EBD (PMMA) 〉 EBD (Nylon) 〉 EBD (PE). This result is consistent with the theoretical prediction. 展开更多
关键词 electric breakdown strength polymer type nanosecond time scale fast polarization phenomenon
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Existence of Periodic Solutions for Neutral-Type Neural Networks with Delays on Time Scales 被引量:1
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作者 Zhenkun Huang Jinxiang Cai 《Journal of Applied Mathematics and Physics》 2013年第4期1-5,共5页
In this paper, we employ a fixed point theorem due to Krasnosel’skii to attain the existence of periodic solutions for neutral-type neural networks with delays on a periodic time scale. Some new sufficient conditions... In this paper, we employ a fixed point theorem due to Krasnosel’skii to attain the existence of periodic solutions for neutral-type neural networks with delays on a periodic time scale. Some new sufficient conditions are established to show that there exists a unique periodic solution by the contraction mapping principle. 展开更多
关键词 Neutral-type NEURAL Networks On Time scales PERIODIC Solution
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On the decomposition problem of neutral type linear large scale control system in the theory of stabilization(1)
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作者 Liu Yong-qing Luo Qi Zou Yong-huaSouth China University of Science and Engineering Hubei Xianning Normal College. China Wuhan Education College. China 《湖北科技学院学报》 1989年第2期1-15,共15页
In this paper we choose the symmetric positive definite solutionof Riccati matrix algebraic equation and,construct a positive defini-tequadratic form V-function and,use Lyapunov deco mpositionequivalence method founde... In this paper we choose the symmetric positive definite solutionof Riccati matrix algebraic equation and,construct a positive defini-tequadratic form V-function and,use Lyapunov deco mpositionequivalence method founded by Liu Yong-qing to obtain the condi-tions of the asymptotic stability of the solution of neutral typelinear large scale control system,the estimate formula of thedecom posing coefficients and time delay are also given. 展开更多
关键词 Large scale NEUTRAL type control system subsystem-closed LO OP SYSTEM stability.
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Genetic Types of Meter-Scale Cyclic Sequences and Fabric Natures of Facies Succession 被引量:16
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作者 Mei Mingxiang Xu Debin Zhou Hongrui Institute of Earth Sciences and Natural Resources, China University of Geosciences, Beijing 100083 《Journal of Earth Science》 SCIE CAS CSCD 2000年第4期3-10,共8页
Different genetic types of meter-scale cyclic sequences in stratigraphic records result from episodic accumulation of strata related to Milankovitch cycles. The distinctive fabric natures of facies succession result f... Different genetic types of meter-scale cyclic sequences in stratigraphic records result from episodic accumulation of strata related to Milankovitch cycles. The distinctive fabric natures of facies succession result from the sedimentation governed by different sediment sources and sedimentary dynamic conditions in different paleogeographical backgrounds, corresponding to high-frequency sea-level changes. Naturally, this is the fundamental criterion for the classification of genetic types of meter-scale cyclic sequences. The widespread development in stratigraphic records and the regular vertical stacking patterns in long-term sequences, the evolution characters of earth history and the genetic types reflected by specific fabric natures of facies successions in different paleogeographical settings, all that show meter-scale cyclic sequences are not only the elementary working units in stratigraphy and sedimentology, but also the replenishment and extension of parasequence of sequence stratigraphy. Two genetic kinds of facies succession for meter-scale cyclic sequence in neritic-facies strata of carbonate and clastic rocks, are normal grading succession mainly formed by tidal sedimentation and inverse grading succession chiefly made by wave sedimentation, and both of them constitute generally shallowing upward succession, the thickness of which ranges from several tens of centimeters to several meters. The classification of genetic types of meter-scale cyclic sequence could be made in terms of the fabric natures of facies succession, and carbonate meter-scale cyclic sequences could be divided into four types: L-M type, deep-water asymmetrical type, subtidal type and peritidal type. Clastic meter-scale cyclic sequences could be grouped into two types: tidal-dynamic type and wave-dynamic type. The boundaries of meter-scale cyclic sequences are marked by instantaneous punctuated surface formed by non-deposition resulting from high-frequency level changes, which include instantaneous exposed punctuated surface, drowned punctuated surface as well as their relative surface. The development of instantaneous punctuated surface used as the boundary of meter-scale cyclic sequence brings about the limitations of Walter's Law on the explanation of facies distribution in time and space, and reaffirm the importance of Sander's Rule on analysis of stratigraphic records. These non-continuous surface could be traced for long distance and some could be correlative within same basin range. The study of meter-scale cyclic sequences and their regularly vertical stacking patterns in long-term sequences indicate that the research into cyclicity of stratigraphic records is a useful way to get more regularity from stratigraphic records that are frequently complex as well as non-integrated. 展开更多
关键词 genetic types fabric natures of facies succession meter-scale cyclic sequences.
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Integral Inequality of Hardy-Type on Time Scales
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作者 Emmanuella Ehui Aribike Yisa Oluwatoyin Anthonio +1 位作者 Kamilu Rauf Michael Oyelami Ajisope 《Advances in Pure Mathematics》 2019年第6期534-543,共10页
Inequalities are essential in the study of Mathematics and are useful tools in the theory of analysis. They have been playing a critical role in the study of the existence and uniqueness properties of solutions of ini... Inequalities are essential in the study of Mathematics and are useful tools in the theory of analysis. They have been playing a critical role in the study of the existence and uniqueness properties of solutions of initial and boundary value problems for differential equations as well as difference equations with their bounds. In this paper, we obtain new integral inequalities mainly by using some known inequalities. Various generalizations of Hardy's inequality are special cases of the results therein. 展开更多
关键词 Time scale Measurable CONVEX FUNCTIONS Hardy-type INEQUALITIES
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逐步Ⅱ型删失下Scaled half-Logistic分布的区间估计 被引量:2
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作者 史爱玲 陈进源 田丽娜 《兰州大学学报(自然科学版)》 CAS CSCD 北大核心 2014年第6期889-891,896,共4页
在逐步Ⅱ型删失数据下,通过构建统计量得到了Scaled half-Logistic分布的参数的置信区间,并借鉴文献[5]的Ⅱ型删失样本模拟算法,给定置信水平,产生了不同删失方式下置信区间长度最短时参数的置信区间.
关键词 scaled half-Logistic分布 尺度参数 逐步Ⅱ型删失 置信区间
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鄂尔多斯盆地东缘临兴—神府区块深部煤储层孔隙结构对甲烷 吸附影响研究
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作者 陈建奇 胡维强 +3 位作者 李洋冰 柳雪青 马立涛 李盼盼 《岩矿测试》 北大核心 2026年第1期116-130,共15页
煤储层孔隙结构认识不清一直是制约深部煤层气勘探开发的关键因素。前人研究认为煤岩孔隙结构参数会对甲烷吸附产生影响,但各孔隙结构参数对甲烷吸附影响强弱缺少系统性研究。本文采用场发射扫描电镜、低温CO_(2)吸附、低温N2吸附、高... 煤储层孔隙结构认识不清一直是制约深部煤层气勘探开发的关键因素。前人研究认为煤岩孔隙结构参数会对甲烷吸附产生影响,但各孔隙结构参数对甲烷吸附影响强弱缺少系统性研究。本文采用场发射扫描电镜、低温CO_(2)吸附、低温N2吸附、高压压汞、甲烷高温高压等温吸附等实验技术,建立煤岩全尺度孔隙结构表征方法,计算各类孔隙孔容、孔比表面积及分形维数等,研究了各孔隙结构参数对甲烷吸附特性的影响。结果表明:①临兴—神府区块煤岩发育大量的植物胞腔孔、气孔、矿物晶间孔和微裂缝等,气孔较为发育,以群、窝状存在;低温N2吸附实验显示研究区煤岩孔隙以狭缝型孔、墨水瓶孔及二者混合孔为主;高压压汞实验结果显示煤岩孔隙类型主要为Ⅱ类过渡型孔隙;②全尺度孔隙结构表征结果显示,研究区煤岩宏孔、微孔孔容发育,宏孔占比66.98%以上,其次为微孔;比表面积以微孔为主,占比超96%;煤岩微孔分形维数大,孔隙形态复杂,其次为介孔,宏孔形态规则;③甲烷吸附量主要与煤岩微、介孔的比表面积、孔容的相关性更强,与微、介孔的分形维数呈正相关性,但相关性弱,与宏孔孔隙参数基本不相关。综上,鄂尔多斯盆地东缘临兴—神府区块8+9#煤岩孔隙结构对甲烷吸附量的影响强弱整体表现为:微孔孔容>微孔比表面积>介孔比表面积>介孔孔容>微孔分形维数>介孔分形维数>宏孔孔隙参数。该认识对于临兴—神府区块深部煤层气的勘探开发具有重要指导意义。 展开更多
关键词 深部煤储层 全尺度孔隙分布 分形维数 等温吸附 孔隙类型
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Diabetes empowerment scores among type 2 diabetes mellitus patients and its correlated factors: A cross-sectional study in a primary care setting in Malaysia 被引量:5
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作者 Thew Hui Zhu Ching Siew Mooi +1 位作者 Nurainul Hana Shamsuddin Ching Siew Mooi 《World Journal of Diabetes》 SCIE CAS 2019年第7期403-413,共11页
BACKGROUND There are limited studies on diabetes empowerment among type 2 diabetes patients,particularly in the primary care setting.AIM To assess the diabetes empowerment scores and its correlated factors among type ... BACKGROUND There are limited studies on diabetes empowerment among type 2 diabetes patients,particularly in the primary care setting.AIM To assess the diabetes empowerment scores and its correlated factors among type 2 diabetes patients in a primary care clinic in Malaysia.METHODS This is a cross sectional study involving 322 patients with type 2 diabetes mellitus(DM)followed up in a primary care clinic.Systematic sampling method was used for patient recruitment.The Diabetes Empowerment Scale(DES)questionnaire was used to measure patient empowerment.It consists of three domains:(1)Managing the psychosocial aspect of diabetes(9 items);(2)Assessing dissatisfaction and readiness to change(9 items);and(3)Setting and achieving diabetes goal(10 items).A score was considered high if it ranged from 100 to 140.Data analysis was performed using SPSS version 25 and multiple linear regressions was used to identify the predictors of total diabetes empowerment scores.RESULTS The median age of the study population was 55 years old.56%were male and the mean duration of diabetes was 4 years.The total median score of the DES was 110[interquartile range(IQR)=10].The median scores of the three subscales were 40 with(IQR=4)for"Managing the psychosocial aspect of diabetes";36 with(IQR=3)for"Assessing dissatisfaction and readiness to change";and 34 with(IQR=5)for"Setting and achieving diabetes goal".According to multiple linear regressions,factors that had significant correlation with higher empowerment scores among type 2 diabetes patients included an above secondary education level(P<0.001),diabetes education exposure(P=0.003),lack of ischemic heart disease(P=0.017),and lower glycated hemoglobin(HbA1c)levels(P<0.001).CONCLUSION Diabetes empowerment scores were high among type 2 diabetes patients in this study population.Predictors for high empowerment scores included above secondary education level,diabetes education exposure,lack of ischemic heart disease status and lower HbA1c. 展开更多
关键词 DIABETES EMPOWERMENT SCORES DIABETES EMPOWERMENT scale type 2 DIABETES Primary care MALAYSIA
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Matrix Padé-Type Method for Computing the Matrix Exponential 被引量:1
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作者 Chunjing Li Xiaojing Zhu Chuanqing Gu 《Applied Mathematics》 2011年第2期247-253,共7页
Matrix Padé approximation is a widely used method for computing matrix functions. In this paper, we apply matrix Padé-type approximation instead of typical Padé approximation to computing the matrix exp... Matrix Padé approximation is a widely used method for computing matrix functions. In this paper, we apply matrix Padé-type approximation instead of typical Padé approximation to computing the matrix exponential. In our approach the scaling and squaring method is also used to make the approximant more accurate. We present two algorithms for computing and for computing with many espectively. Numerical experiments comparing the proposed method with other existing methods which are MATLAB’s functions expm and funm show that our approach is also very effective and reliable for computing the matrix exponential . Moreover, there are two main advantages of our approach. One is that there is no inverse of a matrix required in this method. The other is that this method is more convenient when computing for a fixed matrix A with many t ≥ 0. 展开更多
关键词 MATRIX Padé-type Approximation MATRIX EXPONENTIAL SCALING and Squaring BACKWARD Er-ror
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现代化治理背景下我国城市更新后评估研究述评——基于“类型——尺度”的整体视角 被引量:3
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作者 黄瓴 刘祖康 骆骏杭 《西部人居环境学刊》 北大核心 2025年第2期97-104,共8页
中国式现代化治理目标下,城市更新应承担起高质量发展、实现城市治理体系和治理能力现代化的重要使命。城市更新后评估是城市更新全生命管理周期的重要环节,自2021年衔接城市体检工作以后,其重要性更加突出。在总结我国城市更新后评估... 中国式现代化治理目标下,城市更新应承担起高质量发展、实现城市治理体系和治理能力现代化的重要使命。城市更新后评估是城市更新全生命管理周期的重要环节,自2021年衔接城市体检工作以后,其重要性更加突出。在总结我国城市更新后评估研究的时空特征基础上,本文构建了“类型—尺度”整体分析框架,对当前国内城市更新后评估既有研究进行系统梳理。研究发现,我国城市更新后评估经历了从经济效益到综合效益的价值转变,研究整体呈现滞后性、零碎性特征;不同类型城市更新后评估在相同尺度下的关注重点存在共性,更新类型与空间尺度是影响后评估指标体系差异的主要因素。总体而言,当前城市更新后评估指标构建缺乏对城市现代化治理的深刻理解,评估方法有待改进。最后对现代化治理背景下城市更新后评估研究进行了角色反思与未来展望,以期进一步丰富我国城市更新理论与方法。 展开更多
关键词 城市更新 后评估 现代化治理 类型—尺度 整体视角
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Anisotropic Behavior of Cosmological Models with Exponential and Hyperbolic Scale Factors
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作者 Fakhereh Md. Esmaeili 《Journal of High Energy Physics, Gravitation and Cosmology》 2018年第2期223-235,共13页
In this paper, the cosmological models of the universe are constructed in gravity with choice of the functional in the form ?and . The space-time considered here is Bianchi Type I and the energy momentum tensor is in ... In this paper, the cosmological models of the universe are constructed in gravity with choice of the functional in the form ?and . The space-time considered here is Bianchi Type I and the energy momentum tensor is in the form of perfect fluid. Two cosmological models are presented using a power form of exponential function and a hyperbolic form. The energy conditions along with the state finder diagnostic pair have been obtained and analyzed. 展开更多
关键词 f (R T ) COSMOLOGY HYPERBOLIC scale FACTOR Bianchi type I HUBBLE PARAMETER
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Scale effects of the continental coastline of China 被引量:8
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作者 SU Fenzhen GAO Yi +2 位作者 ZHOU Chenghu YANG Xiaomei FEI Xianyun 《Journal of Geographical Sciences》 SCIE CSCD 2011年第6期1101-1111,共11页
Spatial scale is a fundamental problem in Geography. Scale effect caused by fractal characteristic of coastline becomes a common focus of coastal zone managers and researchers. In this study, based on DEM and remote s... Spatial scale is a fundamental problem in Geography. Scale effect caused by fractal characteristic of coastline becomes a common focus of coastal zone managers and researchers. In this study, based on DEM and remote sensing images, multi-scale continental coastlines of China were extracted and the fractal characteristic was analyzed. The results are shown as follows. (1) The continental coastline of China fits the fractal model, and the fractal dimension is 1.195. (2) The scale significant differences according to uplift effects with fractal dimensions of coastline have and subsidence segments along the continental coastlines of China. (3) The fractal dimension of coastline has significant spatial heterogeneity according to the coastline types. The fractal dimension of sandy coastline located in Luanhe River plain is 1.109. The dimension of muddy coastline located in northern Jiangsu Plain is 1.059, while that of rocky coastline along southeastern Fujian is 1.293. (4) The length of rocky coastline is affected by scale more than that of muddy and sandy coastline. Since coastline is the conjunction of sea, land and air surface, the study of coastline scale effect is one of the scientific bases for the researches on air-sea-land interaction in multi-scales. 展开更多
关键词 scale effect fractal dimension COASTLINE uplift segment subsidence segment coastline type
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宁南黄土区中庄小流域土壤密度坡面变化及尺度效应
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作者 韩新生 许浩 +5 位作者 刘广全 安钰 董立国 王月玲 万海霞 郭永忠 《水土保持研究》 北大核心 2025年第2期72-82,共11页
[目的]分析土壤密度在坡面上的变化特征及尺度效应,探讨土壤密度坡面尺度转换路径,为精准监测土壤密度、科学评价土壤功能、指导土壤资源管理提供理论依据。[方法]在宁夏南部半干旱黄土丘陵区中庄小流域,选择3个退耕还林还草后的典型坡... [目的]分析土壤密度在坡面上的变化特征及尺度效应,探讨土壤密度坡面尺度转换路径,为精准监测土壤密度、科学评价土壤功能、指导土壤资源管理提供理论依据。[方法]在宁夏南部半干旱黄土丘陵区中庄小流域,选择3个退耕还林还草后的典型坡面,按坡位从上至下设置了5个样地,调查各样地的植被类型、土地利用、立地条件等,采用环刀法分层测定了200 cm深度的土壤密度。[结果]在东坡、西坡、南坡,土壤密度随土层加深基本表现为线性增加,土层每加深10 cm土壤密度平均增加0.0062,0.0036,0.0075 g/cm^(3),其原因为植被根系、土壤有机质、压实作用的土层差异。在0—200 cm土层,东坡和南坡土壤密度坡面均值均为1.22 g/cm^(3),低于西坡(1.26 g/cm^(3))。3个坡面土壤密度的坡面变化存在差异,东坡、西坡、南坡沿坡变化表现为逐渐增加或先增后减、先升后降、先降后升,整体上为坡面下部大于上部,主要原因包括植被类型、土地利用、人类活动、恢复年限等坡面差异。以离坡顶水平距离增加100 m土壤密度坡面滑动平均值的变化量评价坡面尺度效应,0—200 cm土层的平均土壤密度坡面尺度效应在东坡为0.032(g/cm^(3))/100 m,在西坡为0.024(g/cm^(3))/100 m(离坡顶0—250 m)和-0.007(g/cm^(3))/100 m(离坡顶250—329 m),在南部为-0.011(g/cm^(3))/100 m(离坡顶0—140 m)和0.018(g/cm^(3))/100 m(离坡顶140—368 m)。构建3个坡面不同坡位样地各土层的土壤密度与坡面均值的比值随离坡顶水平距离增加而变化的关系式(R2>0.80,p<0.0001),且基于拟合关系式预测的土壤密度坡面均值的相对误差均小于2.5%,藉此可由任一坡位样地土壤密度测定值准确便捷地估算坡面均值。[结论]半干旱黄土区土壤密度坡面变化和坡位差异明显,且植被类型、人为干扰、土地利用等对土壤密度坡面分布格局影响较大,未来应加强主要作用因子对土壤密度坡面变化及尺度效应的贡献研究。 展开更多
关键词 土壤密度 坡面变化 尺度效应 植被类型 半干旱黄土区
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Preparation and Characterisation of Collagen from Freshwater Fish Scales 被引量:5
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作者 Fengxiang Zhang Anning Wang +2 位作者 Zhihua Li Shengwen He Lijun Shao 《Food and Nutrition Sciences》 2011年第8期818-823,共6页
Acid-soluble collagen (ASC) and pepsin-solubilized collagen (PSC) were prepared from the waste freshwater carp fish scales. The results of SDS-PAGE showed that purified collagens were composed of at least two differen... Acid-soluble collagen (ASC) and pepsin-solubilized collagen (PSC) were prepared from the waste freshwater carp fish scales. The results of SDS-PAGE showed that purified collagens were composed of at least two different chains which were in accordance with the type I collagen with α chain composition of (α1)2α2. Compared with the carp fish ordinary muscle type I collagen , porcine dermis type I collagen and other seawater fish collagens, freshwater carp fish scales collagen contained relative high half-cystine (Cys-s), but lower denaturation temperature(Td) than the porcine dermis type I collagen. These collagens had evident absorption at 230 nm by UV-Vis spectra. The spectrum X-ray diffraction showed that the collagen remained single-helix and tri-helix configuration with the minimum values of the repeat spacings (d) of about 4.48 ? and 11.87 ?. Therefore, to make more effective use of limited-resources, carp fish scales can be a potential resource for the extraction of type I collagen or gelatin. 展开更多
关键词 CARP Fish scale ASC (Acid-Solubilized Collagens) PSC (pepsin -solubilized collagens) type I COLLAGEN
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Comparison on Efficacy and Safety of Three Inpatient Insulin Regimens for Management of Non-Critical Patients with Type 2 Diabetes
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作者 Eman Said Samar Farid +1 位作者 Nirmeen Sabry May Fawzi 《Pharmacology & Pharmacy》 2013年第7期556-565,共10页
Background: Hyperglycemia in hospitalized patients is associated with poor clinical outcomes. Scheduled Subcutaneous Insulin therapy has been recommended for better glycemic control. Aims: To compare efficacy and safe... Background: Hyperglycemia in hospitalized patients is associated with poor clinical outcomes. Scheduled Subcutaneous Insulin therapy has been recommended for better glycemic control. Aims: To compare efficacy and safety of traditional sliding scale insulin (SSI) versus modified 70/30 insulin versus basal plus supplemental scale (SS) insulin regimens for glycemic control of inpatients with diabetes. Methods: In a prospective trial, 62 patients with diabetes were randomized to receive either hospital SSI (N = 22), or twice daily 70/30 insulin plus supplemental lunchtime insulin for BG ≥ 150 mg/dL (N = 21) or once every night glargine plus prandial glulisine for BG ≥ 150 mg/dL (N = 19). 70/30 insulin and glargine were started respectively at 0.4 and 0.2 U/kg/day for BG ≤ 200 mg/dL or 0.5 and 0.3 U/kg/day for BG above 200 mg/dL. Results: Starting at BG level of 204 ± 68, 200 ± 50 and 241 ± 94 mg/dL in SSI, 70/30 insulin and glargine/glulisine groups respectively, (F(2,35.47) = 1.467, p = 0.244, Welch test), mean daily BG after first day of hospitalization was statistically significant (F(2,35.58) = 7.043, p = 0.003, Welch test) lower in 70/30 insulin group (171 ± 38 mg/dL) compared to (218 ± 71 mg/dL) in SSI group (p = 0.026) and (225 ± 65 mg/dL) in glargine/glulisine group (p = 0.01). Conclusions: With poorly educated nursing staff, basal plus SS insulin failed to provide adequate glycemic control. However, tailored 70/30 insulin regimen resulted in statistically significant glycemic control compared to traditional SSI. 展开更多
关键词 type 2 DM SLIDING scale INSULIN 70/30 INSULIN BASAL INSULIN Supplemental INSULIN
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Enhanced Thermoelectric Performance of Non-equilibrium Synthesized Fe0.4Co3.6Sb12-xGex Skutterudites via Randomly Distributed Multi-scaled Impurity Dots
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作者 章嵩 HU Xuan +3 位作者 杨梅君 CHENG Hong TU Rong ZHANG Lianmeng 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2018年第4期772-777,共6页
The p-type Ge doped Fe0.4Co3.6Sb12-xGex skutterudites with multi-scaled impurity dots(500 nm-2 mm) were successfully prepared by using melt-quenching(MQ) and subsequent spark plasma sintering(SPS) technique. Com... The p-type Ge doped Fe0.4Co3.6Sb12-xGex skutterudites with multi-scaled impurity dots(500 nm-2 mm) were successfully prepared by using melt-quenching(MQ) and subsequent spark plasma sintering(SPS) technique. Compared with traditional method, the new technology significantly shortened the processing time from several days to less than 24 hours. The phase of impurity dots was demonstrated to be CoSb through analysis of X-ray diffraction(XRD) and energy-dispersive spectrum(EDS). Impurity dots were induced by Ge substitution of Sb in the non-equilibrium synthesized process. Due to the abandonment of the long reaction of annealing crystallization, a few of Ge atoms would fail to substitute Sb site of skutterudite in this non-equilibrium synthesized process, leading to that the multi-scaled impurity dots randomly distributed in the matrix of skutterudite Fe0.4Co3.6Sb12-xGex. The combination of multi-scaled impurity dots scattering long wavelength heat-carrying phonons and the point defect scattering short and middle wavelength heat-carrying phonons dramatically made the 22.2% reduction of lattice thermal conductivity. As a result, compared with unsubstituted sample of Fe0.4Co3.6Sb12, the maximum ZT value was increased by 30.5%. Thus, the two marked features of this new synthesis process, the shortened preparation time and the enhanced thermoelectric performance, would make a promising commercial application in the future. 展开更多
关键词 multi-scaled impurity dots Sb site substitution P-type thermoelectric transport properties
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A型肉毒毒素注射治疗丘脑痛11例体会
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作者 孙桂芳 袁志浩 +3 位作者 胡文涛 马兴荣 张博爱 卢宏 《郑州大学学报(医学版)》 北大核心 2025年第1期132-135,共4页
目的:观察A型肉毒毒素注射对丘脑痛的疗效和安全性。方法:11例丘脑痛患者入组。在标记的受累部位一次性注射A型肉毒毒素50~400 U,注射后随访12个月。分别在注射前、注射后1周以及注射后12个月内每月采用VAS评分评估疼痛程度,治疗后4个... 目的:观察A型肉毒毒素注射对丘脑痛的疗效和安全性。方法:11例丘脑痛患者入组。在标记的受累部位一次性注射A型肉毒毒素50~400 U,注射后随访12个月。分别在注射前、注射后1周以及注射后12个月内每月采用VAS评分评估疼痛程度,治疗后4个月进行患者总体感觉改善情况评分(PGIC评分),记录治疗和随访期间的副作用。结果:11例患者中9例完成随访,1例在治疗后4个月失访,1例在治疗后8个月效果下降,自行使用其他药物治疗。9例中男7例,女2例,年龄52~82(68.3±10.8)岁。疼痛持续时间(13.3±3.7)个月,治疗前VAS评分(5.7±0.5)分,治疗后1周VAS评分均值降至2分,说明患者疼痛大为缓解,治疗8个月以后部分患者疗效下降,但治疗后12个月中,总体镇痛效果维持在较低水平(均值1.9~2.8),且较为稳定。根据PGIC评分,7例明显好转,2例轻微好转。注射后1周内1例出现面部不对称和眼睑下垂,1例出现面部不对称,均在5周内自行消失。结论:A型肉毒毒素注射治疗丘脑痛有效且安全。 展开更多
关键词 A型肉毒毒素 丘脑痛 VAS评分
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日常时间管理量表的汉化及信效度检验
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作者 马旖旎 张理想 +1 位作者 赵俐丽 史天陆 《护理研究》 北大核心 2025年第4期617-623,共7页
目的:将日常时间管理量表(Daily Time Management Scale,DTMS)进行汉化,并对其进行信效度检验。方法:遵循Brislin翻译模式进行量表翻译,通过专家咨询和预调查进行文化调适后形成中文版DTMS。采用便利抽样法,选取300例2型糖尿病病人进行... 目的:将日常时间管理量表(Daily Time Management Scale,DTMS)进行汉化,并对其进行信效度检验。方法:遵循Brislin翻译模式进行量表翻译,通过专家咨询和预调查进行文化调适后形成中文版DTMS。采用便利抽样法,选取300例2型糖尿病病人进行横断面调查,分析中文版DTMS的信效度。结果:中文版DTMS项目分析结果显示所有条目均设计合理、区分度良好。量表条目水平的内容效度指数(I-CVI)为0.875~1.000,量表内容效度指数(S-CVI)为0.928。探索性因子分析共提取3个公因子,累计方差贡献率为64.695%。总量表的Cronbach's α系数为0.864,3个维度的Cronbach's α系数分别为0.851,0.834,0.746;重测信度为0.845。中文版DTMS包括工作满意度与生活充实度的协调、生活节奏调整和全面考量的目标取向3个维度,共16个条目。结论:中文版DTMS在2型糖尿病病人中的应用具有良好的信效度,可作为评估2型糖尿病病人日常时间管理的有效工具。 展开更多
关键词 日常时间管理 2型糖尿病 量表 信度 效度
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具有Leslie-Gower和Holling-TypeⅡ型非自治食饵-捕食时标动力学系统的周期解
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作者 官晓莉 李周红 《玉溪师范学院学报》 2012年第4期1-7,共7页
利用重合度理论研究了一类在时标上具有Leslie-Gower和Holling-Ⅱ型非自治食饵-捕食动力学系统,得到了其存在周期解的充分条件.
关键词 周期解 Leslie-Gower和Holling-Ⅱ型 食饵-捕食系统 重合度 时标
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推进新型工业化,用好工业大模型的“超级大脑” 被引量:1
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作者 周云杰 《数字化转型》 2025年第3期10-13,共4页
本文聚焦工业大模型在新型工业化进程中的核心作用,系统阐述其演进趋势、应用价值及发展路径。工业大模型通过多模态融合技术,实现从单点智能到全域协同的升级,推动制造业向数字化、智能化转型。然而,工业领域仍面临数据质量参差不齐、... 本文聚焦工业大模型在新型工业化进程中的核心作用,系统阐述其演进趋势、应用价值及发展路径。工业大模型通过多模态融合技术,实现从单点智能到全域协同的升级,推动制造业向数字化、智能化转型。然而,工业领域仍面临数据质量参差不齐、场景适配难度高、供需错位等挑战。文章提出三项对策:构建国家级工业场景图谱与数据集;支持龙头企业示范应用;扶持平台企业赋能中小企业。通过夯实技术底座、强化场景创新与生态协同,工业大模型将加速推动产业升级,为新型工业化注入核心动能。 展开更多
关键词 新型工业化 工业大模型 人工智能 数字化转型
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