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不同载荷条件下三种内固定方式治疗PauwelsⅢ型股骨颈骨折的有限元分析
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作者 李正刚 尚学红 +5 位作者 吴张 李红 孙朝军 陈华东 孙哲 杨毅 《中国组织工程研究》 CAS 北大核心 2025年第3期455-463,共9页
背景:治疗PauwelsⅢ型股骨颈骨折的最佳内固定方式仍未达成共识,既往相关有限元分析大多采用单一简化载荷条件,对于常用内固定装置的生物力学特性还需进一步探究。目的:通过有限元方法分析空心加压螺钉、动力髋螺钉和股骨颈系统治疗Pauw... 背景:治疗PauwelsⅢ型股骨颈骨折的最佳内固定方式仍未达成共识,既往相关有限元分析大多采用单一简化载荷条件,对于常用内固定装置的生物力学特性还需进一步探究。目的:通过有限元方法分析空心加压螺钉、动力髋螺钉和股骨颈系统治疗PauwelsⅢ型股骨颈骨折在单腿站立载荷及侧方跌倒载荷条件下的生物力学特性。方法:通过CT扫描获取健康成人股骨DICOM数据,导入Mimics 15.0软件,得到骨组织的粗糙模型,再通过Geomagics软件对Mimics导出的数据进行优化处理,然后根据空心加压螺钉、动力髋螺钉和股骨颈系统的临床应用参数采用Pro/E软件建立3种内固定模型并与股骨模型组装,最后导入Ansys软件进行加载、计算,分析3种内固定模型在单腿站立载荷及侧方跌倒载荷的不同工况下股骨和内固定的应力分布和位移情况,以及股骨距和Ward三角区的应力特点。结果与结论:(1)单腿站立载荷及侧方跌倒载荷下,3种内固定模型的股骨近端应力均主要分布在股骨颈骨折端内上方,3种内固定模型的股骨近端、骨折端、Ward三角以及股骨距的应力峰值均为股骨颈系统内固定模型最小,空心加压螺钉内固定模型最大;(2)单腿站立载荷及侧方跌倒载荷下,3种内固定模型的股骨近端位移峰值均位于股骨头顶端,且位移峰值均为股骨颈系统内固定模型最小,空心加压螺钉内固定模型最大;(3)3种内固定模型在单腿站立及侧方跌倒载荷条件下内固定的位移峰值均位于内固定装置上方顶端,且位移峰值均为股骨颈系统内固定模型最小,空心加压螺钉内固定模型最大;(4)3种内固定模型在单腿站立及侧方跌倒载荷条件下内固定的应力均主要集中在内固定装置的骨折端附近区域,且内固定应力峰值均为股骨颈系统内固定模型最小,空心加压螺钉内固定模型最大;(5)结果表明,股骨颈系统的机械稳定性最佳,但是可能存在对于骨折端和股骨距应力遮挡的风险;股骨颈系统的内固定装置应力更为分散,内固定断裂风险更低。 展开更多
关键词 股骨颈骨折 内固定 有限元分析 生物力学 单腿站立 侧方跌倒 股骨距 ward三角
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Study on anatomy and clinical application of Kambin’s triangle and modified quadrangle
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作者 Qiu-Yu Peng Huan-Xiong Chen +3 位作者 Zhen-Hao Zhong Xue-Jian Yang Guo-Jun Li Zhi-Bin Meng 《Journal of Hainan Medical University》 2022年第15期24-29,共6页
Objective:We through the anatomy of cadavers to study the"Kambin’s triangle"in the safe working area of lumbar intervertebral foramen and to provide anatomical reference for clinical lumbar fusion through K... Objective:We through the anatomy of cadavers to study the"Kambin’s triangle"in the safe working area of lumbar intervertebral foramen and to provide anatomical reference for clinical lumbar fusion through Kambin’s triangle approach.Methods:five complete cadaveric specimens were taken,the soft tissue of the lumbar back was removed,the transverse process,upper and lower articular processes and part of the vertebral lamina were bitten,the Kambin’s triangle area of the lumbar spine was completely exposed,the bottom edge and height of the Kambin’s triangle were measured,and the area of the Kambin’s triangle was calculated;Using Kirschner wire,pull and fix the traveling nerve root to make the Kambin’s triangle into a rectangle,measure the length of the bottom edge and height again,calculate the area,and compare the two groups of data.Results:the average height of the Kambin’s triangle was 11.20mm±2.10mm,and the average height of the improved four corners was 11.19mm±1.93mm.The height of the improved four corners was slightly shorter than that of the Kambin’s triangle.There was a significant correlation between the two,but the difference was not statistically significant.The average bottom of Kambin’s triangle is 10.78mm±1.95mm,and the average bottom of improved four corners is 12.14mm±1.78mm.The length of the bottom edge of improved four corners is greater than that of Kambin’s triangle.There is a significant correlation between them,and the difference is statistically significant;The average area of Kambin’s triangle is 61.79mm^(2)±20.71mm^(2),and the area of improved four corners is 137.71mm^(2)±38.20mm^(2).The area of improved four corners is significantly larger than that of Kambin’s triangle.There is a significant correlation between the two,and the difference is statistically significant.Conclusion:there is a narrow right angle triangle area surrounded by traveling nerve root,dural sac and superior endplate of lower vertebral body in the lumbar intervertebral foramen.If the traveling nerve root is pulled and fixed to turn the traditional Kambin’s triangle into a quadrilateral,the bottom edge of the Kambin’s triangle area can be significantly longer and the area can be significantly expanded,which can be operated more safely. 展开更多
关键词 Kambin’s triangle Transforaminal lumbar interbody fusion Lumbar vertebra Transforaminal percutaneous endoscopic
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The U.S.Defense "Iron Triangle" in Policy-Making Process
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作者 Yang Mingjie 《Contemporary International Relations》 2002年第8期1-20,共20页
Over the years the defense industry has become a de facto participant in the policy-making process. As in other areas dominated by big business interests, a policy sub-government of "iron triangle" has emerg... Over the years the defense industry has become a de facto participant in the policy-making process. As in other areas dominated by big business interests, a policy sub-government of "iron triangle" has emerged. In the view of some American scholars, such an "iron triangle" as a political relationship that brings together . 展开更多
关键词 in Policy-Making Process Iron triangle The U.s.Defense
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N-Summet-k and Its Application in the Construction of Pascal Triangle and Pascal Matrix
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作者 Neelam Jeevan Kumar 《Journal of Applied Mathematics and Physics》 2016年第1期169-177,共9页
Summetor is an operator used in the mathematics to calculate the special numbers like binomial coefficients and combinations of group elements. It has many applications in algebra, matrices like calculation of pascal ... Summetor is an operator used in the mathematics to calculate the special numbers like binomial coefficients and combinations of group elements. It has many applications in algebra, matrices like calculation of pascal triangle elements and pascal matrix formation, etc. This paper explains about its functions and properties of N-Summet-k. The result of variation between N and k is shown in tabulation. 展开更多
关键词 summetor N-summet-k Binomial Coefficients Pascal’s triangle Pascal’s Matrix
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Zeno and the Wrong Understanding of Motion—A Philosophical-Mathematical Inquiry into the Concept of Finitude as a Peculiarity of Infinity
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作者 Andreas Herberg-Rothe 《Journal of Applied Mathematics and Physics》 2024年第3期912-929,共18页
In contrast to the solutions of applied mathematics to Zeno’s paradoxes, I focus on the concept of motion and show that, by distinguishing two different forms of motion, Zeno’s apparent paradoxes are not paradoxical... In contrast to the solutions of applied mathematics to Zeno’s paradoxes, I focus on the concept of motion and show that, by distinguishing two different forms of motion, Zeno’s apparent paradoxes are not paradoxical at all. Zeno’s paradoxes indirectly prove that distances are not composed of extensionless points and, in general, that a higher dimension cannot be completely composed of lower ones. Conversely, lower dimensions can be understood as special cases of higher dimensions. To illustrate this approach, I consider Cantor’s only apparent proof that the real numbers are uncountable. However, his widely accepted indirect proof has the disadvantage that it depends on whether there is another way to make the real numbers countable. Cantor rightly assumes that there can be no smallest number between 0 and 1, and therefore no beginning of counting. For this reason he arbitrarily lists the real numbers in order to show with his diagonal method that this list can never be complete. The situation is different if we start with the largest number between 0 and 1 (0.999…) and use the method of an inverted triangle, which can be understood as a special fractal form. Here we can construct a vertical and a horizontal stratification with which it is actually possible to construct all real numbers between 0 and 1 without exception. Each column is infinite, and each number in that column is the starting point of a new triangle, while each row is finite. Even in a simple sine curve, we experience finiteness with respect to the y-axis and infinity with respect to the x-axis. The first parts of this article show that Zeno’s assumptions contradict the concept of motion as such, so it is not surprising that this misconstruction leads to contradictions. In the last part, I discuss Cantor’s diagonal method and explain the method of an inverted triangle that is internally structured like a fractal by repeating this inverted triangle at each column. The consequence is that we encounter two very different methods of counting. Vertically it is continuous, horizontally it is discrete. While Frege, Tarski, Cantor, Gödel and the Vienna Circle tried to derive the higher dimension from the lower, a procedure that always leads to new contradictions and antinomies (Tarski, Russell), I take the opposite approach here, in which I derive the lower dimension from the higher. This perspective seems to fail because Tarski, Russell, Wittgenstein, and especially the Vienna Circle have shown that the completeness of the absolute itself is logically contradictory. For this reason, we agree with Hegel in assuming that we can never fully comprehend the Absolute, but only its particular manifestations—otherwise we would be putting ourselves in the place of the Absolute, or even God. Nevertheless, we can understand the Absolute in its particular expressions, as I will show with the modest example of the triangle proof of the combined horizontal and vertical countability of the real numbers, which I developed in rejection of Cantor’s diagonal proof. . 展开更多
关键词 Zeno False Assumptions about Motion Finitude INFINITY Cantor’s Diagonal Method Inverted triangle as a Different Method Vertical and Horizontal Dimensions Quantum Theory Relativity of space and Time Depending on Velocity
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基于Ward’s方法的k-平均优化算法及其应用 被引量:7
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作者 邱苏林 王丽珍 《计算机工程与应用》 CSCD 北大核心 2008年第31期169-172,共4页
通过对k-平均算法存在不足的分析,提出了一种基于Ward’s方法的k-平均优化算法。算法首先在用Ward’s方法对样本数据初步聚类的基础上,确定合适的簇数目、初始聚类中心等k-平均算法的初始参数,并进行孤立点检测、删除;基于上述处理再采... 通过对k-平均算法存在不足的分析,提出了一种基于Ward’s方法的k-平均优化算法。算法首先在用Ward’s方法对样本数据初步聚类的基础上,确定合适的簇数目、初始聚类中心等k-平均算法的初始参数,并进行孤立点检测、删除;基于上述处理再采用传统k-平均算法进行聚类。将优化的k-平均算法应用到罪犯人格类型分析中,实验结果表明,该算法的效率、聚类效果均明显优于传统k-平均算法。 展开更多
关键词 K-平均算法 ward’s方法 簇数目 初始聚类中心 孤立点检测
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关于Wards三角区的探讨 被引量:13
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作者 朱晓颖 朱汉民 张雪梅 《中国骨质疏松杂志》 CAS CSCD 2005年第4期460-463,共4页
目的研究Wards三角区骨密度值的临床意义。方法采用美国HologicDelphiA双能X线骨密度仪测定385名20~80岁志愿者(男230例,女155例)左股骨骨密度及113例左右股骨骨密度,观察Wards三角区的变化规律及临床特点。结果①有40.4%~55.8%的青年... 目的研究Wards三角区骨密度值的临床意义。方法采用美国HologicDelphiA双能X线骨密度仪测定385名20~80岁志愿者(男230例,女155例)左股骨骨密度及113例左右股骨骨密度,观察Wards三角区的变化规律及临床特点。结果①有40.4%~55.8%的青年人Wards三角区的具体位置计算机很难确定,Wards三角区大部分与解剖部位不相对应;②由计算机自动定位的Wards三角区小方块位置取样误差比较大;③Wards三角区骨密度值的精确度误差和变异系数百分比最大;④腿的位置旋转过度或旋转不足都能引起骨密度的变化;⑤正常人双腿骨密度值无显著性差异。结论Wards三角区骨密度值不能用于诊断或随访。 展开更多
关键词 骨密度 ward's三角区 精确度 骨质损失
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Shift, the Law of the Invention of Zero
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作者 Emmanuel Cadier Anaxhaoza 《Advances in Pure Mathematics》 2023年第5期237-249,共13页
After posing the axiom of linear algebra, the author develops how this allows the calculation of arbitrary base powers, which provides an instantaneous calculation of powers in a particular base such as base ten;first... After posing the axiom of linear algebra, the author develops how this allows the calculation of arbitrary base powers, which provides an instantaneous calculation of powers in a particular base such as base ten;first of all by developing the any base calculation of these powers, then by calculating triangles following the example of the “arithmetical” triangle of Pascal and showing how the formula of the binomial of Newton is driving the construction. The author also develops the consequences of the axiom of linear algebra for the decimal writing of numbers and the result that this provides for the calculation of infinite sums of the inverse of integers to successive powers. Then the implications of these new forms of calculation on calculator technologies, with in particular the storage of triangles which calculate powers in any base and the use of a multiplication table in a very large canonical base are discussed. 展开更多
关键词 AXIOM Axiom of Linear Algebra {ALA} Any Base Calculation ABC Theory Number’s Origin Number Theory Newton’s Binomial Formula Pascal’s triangle Base Z Canonical Bases Calculator Revolution Infinite sums of Inverse of Integer to the successive Powers Information Completion Theory Cipher Factorizations That Are Numbers Infinite Numbers That Are Infinite sums
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Ward三角区再研究 被引量:8
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作者 孙蕴 贺丽英 +3 位作者 马兆坤 潘克梫 李英亭 要文娟 《中国骨质疏松杂志》 CAS CSCD 北大核心 2016年第6期706-710,717,共6页
目的深入研究Ward三角区骨密度的临床意义。方法采用美国Norland XR-600双能X线骨密度仪,通过测定1189例病人的左股骨近端骨密度,评估计算机自动生成的Ward三角区的特点;通过测定30例志愿者左右股骨近端骨密度,评估不同肢体侧别的骨密... 目的深入研究Ward三角区骨密度的临床意义。方法采用美国Norland XR-600双能X线骨密度仪,通过测定1189例病人的左股骨近端骨密度,评估计算机自动生成的Ward三角区的特点;通过测定30例志愿者左右股骨近端骨密度,评估不同肢体侧别的骨密度是否存在差异;通过对72例随访病人3~6月内进行左股骨近端骨密度测定,观察Ward三角区骨密度在较短时间内随时间的变化规律及临床特点。结果 1Ward三角区由计算机根据骨密度最低值自动搜索形成,大部分受试者(86.7%)Ward三角区位于股骨颈底边附近,少部分受试者(5.2%)位于股骨颈外,以大粗隆最为常见,与解剖位置不完全对应;2部分受试者(8.7%)Ward三角区骨密度并非股骨上段最低值,最低值出现在大粗隆。3计算机自动生成的Ward三角区小方块前后两次位置无明显变化。4Ward三角区骨密度值的精确度误差(2.27%)大于股骨颈(1.05%)及大粗隆(1.57%)。5正常人双髋骨密度无显著性差异(P=0.32,P〉0.05)。672例随访患者Ward三角区的骨密度(BMD)变化先于股骨颈及正位腰椎出现。结论髋关节采用标准体位摆放,Ward三角区位置较为固定,可用于临床随访。 展开更多
关键词 骨密度 ward三角区
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基于改进Sobel算子的遥感图像道路边缘检测方法 被引量:31
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作者 谭媛 黄辉先 +1 位作者 徐建闽 陈任 《国土资源遥感》 CSCD 北大核心 2016年第3期7-11,共5页
从遥感图像中提取道路边缘可以大量简化道路网的测绘与规划工作。传统边缘检测算子由于方向和模板尺寸的局限性,易造成检测结果中边缘点散乱、不连续或过多边缘点误判。基于道路边缘完整且连续的特点,针对传统检测效果并不理想的问题,... 从遥感图像中提取道路边缘可以大量简化道路网的测绘与规划工作。传统边缘检测算子由于方向和模板尺寸的局限性,易造成检测结果中边缘点散乱、不连续或过多边缘点误判。基于道路边缘完整且连续的特点,针对传统检测效果并不理想的问题,提出了一种改进的Sobel算子,即5×5的8方向模板。从Sobel算子的基本原理出发,根据Pascal三角形理论推导出各方向的最优模板。研究表明,该算子不仅能较好地检测出更多方向上的边缘,而且能有效减少误判点,检测出的边缘线条更加平滑、完整,轮廓清晰且连续性好,尤其在弯曲道路检测中表现得更为突出,优于其他算子的检测效果。 展开更多
关键词 遥感图像 道路边缘 sOBEL算子 8方向 Pascal三角形
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基于Ward/REI等值理论的配网合环稳态电流计算 被引量:9
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作者 宣科 贾云清 祝洪博 《东北电力大学学报》 2011年第1期43-47,共5页
针对配网合环系统进行计算时,无法获取上级电网实时信息,需要对外部网络进行适当等值的问题,提出一种基于Ward/REI等值理论建立合环网络的等值模型,利用Ward型等值法具有良好数值解的特点,对外网进行Ward等值。在实时情况下,当系统的运... 针对配网合环系统进行计算时,无法获取上级电网实时信息,需要对外部网络进行适当等值的问题,提出一种基于Ward/REI等值理论建立合环网络的等值模型,利用Ward型等值法具有良好数值解的特点,对外网进行Ward等值。在实时情况下,当系统的运行参数发生变化后,在边界节点处将会出现失配功率,以边界节点失配功率,增广一个校正REI网络来修正等值参数,使等值网满足在线分析对等值网准确度的需要。实际算例结果表明了该方法的有效性与实用性,对实际配网的调度运行提供了理论依据和技术支撑。 展开更多
关键词 配电网 合环操作 ward/REI等值 潮流计算 稳态电流
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Fuzzy传递闭包与Fuzzy分类矩阵的S-K-Q判定定理 被引量:2
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作者 史开泉 汪保明 《模糊系统与数学》 CSCD 1990年第2期92-97,共6页
本文给出了Fuzzy传递闭包(?)~*的Fuzzy矩形、Fuzzy三角形及Fuzzy分类矩阵R_λ的Boole矩形、Boole三角形的概念,提出了(?)~*、R_λ的S-K-Q判定定理。
关键词 s-K-Q定理 模糊传递闭包 模糊分类矩阵
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基于T-S模糊模型的太阳位置算法 被引量:5
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作者 彭海仔 《上海海事大学学报》 北大核心 2014年第2期81-84,共4页
为实现太阳位置跟踪以达到提高太阳能利用率的目的,提出一种基于T-S模糊模型的太阳位置算法.该算法根据在固定地点太阳高度角随时间变化的二元函数,建立高度角为输出的T-S模糊模型,通过该模型计算出太阳的位置.该模型利用三角形隶属度... 为实现太阳位置跟踪以达到提高太阳能利用率的目的,提出一种基于T-S模糊模型的太阳位置算法.该算法根据在固定地点太阳高度角随时间变化的二元函数,建立高度角为输出的T-S模糊模型,通过该模型计算出太阳的位置.该模型利用三角形隶属度函数使运算量降低,并易于实现.通过使用传统算法与基于T-S模糊模型的太阳位置算法计算出的上海临港某地4天的高度角和方位角变化曲线的对比,表明该方法具有较高的精度,能够满足普通光伏系统的要求. 展开更多
关键词 太阳位置 视日跟踪 T-s模糊模型 三角形隶属度函数 光伏发电
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基于Euler/N-S方程的跨音速非线性静气动弹性问题研究 被引量:2
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作者 郭承鹏 董军 +1 位作者 杨庆华 李俊甫 《航空计算技术》 2006年第6期40-44,共5页
在C-H网格的基础上,采用Jam eson的中心差分有限体积法求解Eu ler/N-S方程,采用结构影响系数法计算结构的弹性变形,用三角元面积加权法和常体积转换法(CVT)实现流固耦合。
关键词 有限体积法 Euler/N—s方程 三角元面积加权法 柔度影响系数法 常体积转换法 流固耦合
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球面上的Erds-Mordell不等式
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作者 司林 何斌吾 冷岗松 《上海大学学报(自然科学版)》 CAS CSCD 2004年第1期56-58,共3页
引进球面三角形的可行点的概念,把平面上的Erd¨os Mordell不等式推广到三维欧氏空间R3中的球面上.
关键词 Erdǒs-Mordell不等式 球面三角形 球面距离
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Erds-Florian不等式的加强(英文)
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作者 陈计 李广兴 《宁波大学学报(理工版)》 CAS 1989年第2期12-14,共3页
本文提出了关于Erds-Florian不等式的一种加强形式,并借助于新建立的分析不等式验证了一些特殊情形。
关键词 Erdi(o|¨)s不等式 三角形
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“5S管理”在肝胆神经外科病区环境管理中的效果分析 被引量:3
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作者 彭瑛 王霞 吴君 《当代医学》 2016年第33期9-11,共3页
目的 分析探讨5 S管理在肝胆神经外科病区环境管理中的效果,对其管理应用价值进行总结。方法 选择2015年3-6月肝胆神经外科治疗出院的30例患者作为对照组,实施5 S管理后,选取7-10月治疗出院的30例患者作为观察组。对2组患者进行问卷调查... 目的 分析探讨5 S管理在肝胆神经外科病区环境管理中的效果,对其管理应用价值进行总结。方法 选择2015年3-6月肝胆神经外科治疗出院的30例患者作为对照组,实施5 S管理后,选取7-10月治疗出院的30例患者作为观察组。对2组患者进行问卷调查,对比分析患者满意度,结合5 S管理前后护理部环境检查科室的得分比,对环境管理效果进行研究。结果 观察组患者的满意度为(98.3±7.8)%,护理部检查得分为(97.4±3.8)%,明显优于对照组指标,差异有统计学意义(P〈0.05)。结论 5 S管理在肝胆神经外科病区环境管理中有利于创建和管理整洁清爽的环境,改善工作心情,提升患者住院体验,树造医疗卫生行业良好的服务形象,故该管理模式值得在肝胆神经外科病区大力推广和实践。 展开更多
关键词 5s管理 肝胆神经外科 病区环境管理效果
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S波段高增益Vivaldi天线设计 被引量:5
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作者 王蒙蒙 王学田 +1 位作者 高洪民 王军虎 《微波学报》 CSCD 北大核心 2020年第S01期105-108,共4页
本文设计了一种工作在S波段超宽带、高增益的Vivaldi天线。该天线以传统Vivaldi天线为出发点,设计主辐射贴片结构为槽线渐变辐射器,引入开槽设计和三角形引向器进一步提高天线的整体辐射性能。馈电结构采用易于加工的渐变微带线转槽线... 本文设计了一种工作在S波段超宽带、高增益的Vivaldi天线。该天线以传统Vivaldi天线为出发点,设计主辐射贴片结构为槽线渐变辐射器,引入开槽设计和三角形引向器进一步提高天线的整体辐射性能。馈电结构采用易于加工的渐变微带线转槽线耦合结构进行馈电,实现不平衡结构到平衡结构的转变。合理选择了介电常数为3.66的Rogers RO4350C介质基板材料,天线的总体尺寸为100mm×80mm×1.5mm。仿真结果表明,在2~4GHz的带宽内驻波比小于1.5,增益达到6.7 d B,且方向图的一致性较好。 展开更多
关键词 s波段 高增益 微带线转槽线巴伦 矩形槽线 三角形引向器
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Scott Campbell理论对城市可持续发展规划的影响研究 被引量:1
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作者 汝小芳 王红扬 孙明芳 《华中科技大学学报(城市科学版)》 CAS 2007年第2期86-90,共5页
由于概念本身并未提供解决发展与保护、公平与效率之间矛盾的有效方案,规划中对可持续发展原则的落实不可避免陷入困境。美国学者Scott Campbell关于可持续发展的城市规划理论是迄今对可持续发展原则较具操作性的阐释之一。对其实践可... 由于概念本身并未提供解决发展与保护、公平与效率之间矛盾的有效方案,规划中对可持续发展原则的落实不可避免陷入困境。美国学者Scott Campbell关于可持续发展的城市规划理论是迄今对可持续发展原则较具操作性的阐释之一。对其实践可持续的方式作了解读,进而基于规划师视角探讨了实现“城市可持续发展规划”的可能路径:规划蓝图必须以兼顾“绿色、利润、公平”为终极理想;规划行动必须以不断协调“资产、资源、发展矛盾”为导向;规划师作用的发挥必须以不断明确自身立场为前提。 展开更多
关键词 城市可持续发展规划 “规划师三角” 规划师 城市可持续发展 sCOTT CAMPBELL
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Average temperature calculation for straight single-row-piped frozen soil wall 被引量:7
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作者 XiangDong Hu SiYuan She RuiZhi Yu 《Research in Cold and Arid Regions》 2011年第2期124-131,共8页
The average temperature of frozen soil wall is an essential parameter in the process of design, construction, and safety manage- ment of artificial ground freezing engineering. It is the basis of calculating frozen s... The average temperature of frozen soil wall is an essential parameter in the process of design, construction, and safety manage- ment of artificial ground freezing engineering. It is the basis of calculating frozen soil's mechanical parameters, fiarther prediction of bearing capacity and, ultimately, safety evaluation of the frozen soil wall. Regarding the average temperature of sin- gle-row-piped frozen soil wall, this paper summarizes several current calculation methods and their shortcomings. Furthermore, on the basis of Bakholdin's analytical solution for the temperature field under straight single-row-piped freezing, two new calcula- tion models, namely, the equivalent trapezoid model and the equivalent triangle model, are proposed. These two approaches are used to calculate the average temperature of a certain cross section which indicates the condition of the whole frozen soil wall. Considering the possible parameter range according to the freezing pipe layout that might be applied in actual construction, this paper compares the average temperatures of frozen soil walls obtained by the equivalent trapezoid method and the equivalent tri- angle method with that obtained by numerical integration of Bakholdin's analytical solution. The results show that the discrepancies are extremely small and these two new approaches are better than currently prevailing methods. However, the equivalent triangle method boasts higher accuracy and a simpler formula compared with the equivalent trapezoid method. 展开更多
关键词 artificial ground freezing single-row-piped freezing frozen soil wall average temperature equivalent trapezoid method equivalent triangle method Bakholdin's solution
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