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Effects of mean shear on the vortex identification and the orientation statistics

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Theoretical & Applied Mechanics Letters 2023年第4期13卷 280-286页

作者： Tianyi Bai Cheng Cheng lin fu Department of Mechanical and Aerospace Engineering The Hong Kong University of Science and TechnologyHong Kong 999077China Department of Mathematics The Hong Kong University of Science and TechnologyHong Kong 999077China HKUST Shenzhen-Hong Kong Collaborative Innovation Research Institute Shenzhen 815057China

This work compares the threshold applied to the swirling strength as well as the vortex orientation statistics in the total and fluctuating velocity fields using direct numerical simulations of compressible and incompressible turbulent channel *** is concluded that the difference in the swirling strength for vortex identification is minimal in the logarithmic region such that these two situations share the same *** the vortex orientation,the inclination angle remains ***,as the wall-normal distance increases,a more and more obvious distinction is noticed for its orientation with respect to the spanwise(z)*** is mainly due to their intrinsic differences and attendant contrasting preference for the vortex identification,i.e.,vortices rotating in the−z direction for the total velocity field and in the z direction for the fluctuating *** observations function as a reasonable explanation for various remarks in previous studies.

关键词： Vortex Compressible wall-bounded turbulence Turbulence structure Channel flows

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郑州日产P20车架焊接线方案设计

汽车科技 2024年第3期 92-100页

作者：付琳王海礁丁鹤东风设备制造有限公司十堰442022

车架是汽车整车的重要组成部分,本文通过对车架焊接线工艺方案的介绍,阐述了车架焊接线的一些设计要点和设计思路,对今后类似车架焊接线的设计有一定的参考价值。

关键词：车架焊接线方案设计

Numerical simulation study on penetration performance of depleted Uranium(DU)alloy fragments

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Defence Technology（防务技术） 2021年第1期17卷 50-55页

作者： fu-lin Zhu Yang Chen Gui-li Zhu Sichuan Aerospace System Engineering Institute Chengdu610100SichuanChina

Due to its high strength,high density,high hardness and good penetration capabilities,Depleted uranium alloys have already shined in armor-piercing *** should also be a lot of room for improvement in the application of fragment killing ***,regarding the performance of the depleted uranium alloy to penetrate the target plate,further investigation is needed to analyze its advantages and disadvantages compared to tungsten *** study the difference in penetration performance between depleted uranium alloy and tungsten alloy fragments,firstly,a theoretical analysis of the adiabatic shear sensitivity of DU and tungsten alloys was given from the perspective of material constitutive ***,taking the cylindrical fragment penetration target as the research object,the penetration process and velocity characteristics of the steel target plates penetrated by DU alloy fragment and tungsten alloy fragment were compared and analyzed,by using finite element software ANSYS/LS-DYNA and Lagrange ***,the influence of different postures when impacting target and different fragment shapes on the penetration results is carried out in the *** results show that in the penetration process of the DU and tungsten alloy fragments,the self-sharpening properties of the DU alloy can make the fragment head sharper and the penetrating ability *** the same conditions,the penetration capability of cylindrical fragment impacting target in vertical posture is better than that in horizontal posture,and the penetration capability of the spherical fragment is slightly better than that of cylindrical fragment.

关键词： Depleted uranium alloy Constitutive model Adiabatic shear Penetration performance Numerical simulation

乡村庭院景观创新设计模式探索与实践——以晋江英林镇西埔村为例

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工业设计 2024年第3期 60-63页

作者：付琳尹金龙丁铮福建农林大学风景园林与艺术学院福州350000

研究以乡村庭院景观与经济产业的融合为切入点,探讨乡村庭院的研究现状、存在问题与发展的现实意义,提出庭院景观与经济产业融合的五种“新”的庭院设计模式,以福建省泉州市晋江市英林镇西埔村为设计实践基地,结合实地调研的情况,对存... 详细信息

研究以乡村庭院景观与经济产业的融合为切入点,探讨乡村庭院的研究现状、存在问题与发展的现实意义,提出庭院景观与经济产业融合的五种“新”的庭院设计模式,以福建省泉州市晋江市英林镇西埔村为设计实践基地,结合实地调研的情况,对存在问题进行具体分析,针对问题提出策略,并将提出的创新型设计模式应用于规划中。以期通过深入研究乡村庭院的营造模式,为优化和提升乡村庭院的设计与发展提供理论依据和实践指导。

关键词：乡村庭院景观经济产业西埔村

Development in mechanisms of ischemic mitral regurgitation

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Chinese Medical Journal 2013年第9期126卷 1766-1770页

作者： HUANG Wei-lin fu Qiang Department of Cardiology Zhujiang Hospital Southern Medical University Guangzhou Guangdong 510280 China

Objective The clinical diagnosis and treatment of ischemia mitral regurgitation （IMR） remained difficult because of its unclear mechanisms. This paper reviews studies on the mechanisms of IMR during the last 20 years, and discusses the relevance of the various mechanisms. Data sources Data used in this review were mainly from CNKI and Pubmed in English. The search terms were ＂ischemia mitral regurgitation mechanism＂, ＂myocardial infarction＂ AND ＂mitral regurgitation＂. Study selection Articles were selected if they involved mechanisms of IMR. Results IMR is one of the common complications of coronary artery disease. But currently, the clinical diagnosis and treatment of IMR remained difficult because of its unclear mechanisms. Conclusions For now, dominating theory of ischemic mitral regurgitation mechanisms are left ventricular remodeling, imbalance of leaflet tethering and the closing force, left ventricular dysfunction, changes in spatial structure of the annulus and the dyssynchrony of the left ventricular electromechanical activity.

关键词： myocardial ischemia mitral regurgitation mitral valve insufficiency

Computing the k-error joint linear complexity of binary periodic multisequences

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The Journal of China Universities of Posts and Telecommunications 2013年第6期20卷 96-101页

作者： LI fu-lin ZHU Shi-xin School of Mathematics Hefei University of Technology

Complexity measures for multisequences over finite fields, such as the joint linear complexity and the k-error joint linear complexity, play an important role in cryptology. In this paper we study a fast algorithm, presented by Venkateswarlu A, to computer the k-error joint linear complexity of a binary periodic multisequence. In this paper, the aim is mainly to complement the theoretical derivation and proof of the existing algorithm. Moreover, our algorithm reduces computation.

关键词： cryptology multisequence algorithm joint linear complexity k-error joint linear complexity

PARAMETERS OF WATER CIRCULATION NETWORK FOR A DISTRICT HEATING AND COOlinG SYSTEM

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Journal of Hydrodynamics 2000年第1期12卷 87-95页

作者： fu, lin Pan, Jihong Jiang, Yi Shandong Univ of Technology Jinan China

In a district heating and cooling system, i.e. Beijing combined heating cooling and power (CHCP) system studied here, the high temperature water generated by two cogeneration plants circulates through a network between the plants and heat substations. At heat substations, the supply water of high temperature from the network drives absorption chillers for air-conditioning in summer and meets space heating demands in winter or domestic hot water demands by heat exchangers in the whole year. The parameters, i.e. supply/return water temperatures in the network, have a great impact on primary energy consumption (PEC) of the absorption chillers, circulation pumps and domestic hot water (DHW), which is studied in this paper.

关键词： Boiler circulation Energy utilization Hot water heating Parameter estimation Water cooling systems

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白内障治疗的多样化和发展前景

中华眼外伤职业眼病杂志 2024年第7期46卷 552-557页

作者：付琳郭隽王颖杨前 116001 116001

白内障是临床常见的眼部疾病。手术治疗是目前主要的手段。屈光性白内障手术在提高患者术后脱镜率、改善患者术中体验和获得良好视觉质量等需求的推动下，治疗手段日益多样化。眼球生物测量设备和屈光度计算公式的不断更新，人工晶状体... 详细信息

白内障是临床常见的眼部疾病。手术治疗是目前主要的手段。屈光性白内障手术在提高患者术后脱镜率、改善患者术中体验和获得良好视觉质量等需求的推动下，治疗手段日益多样化。眼球生物测量设备和屈光度计算公式的不断更新，人工晶状体研究向多焦点、连续视程方向不断发展，以及飞秒激光辅助技术及手术系统的不断应用，极大推进了白内障手术治疗向更有效、更安全、更精准的方向发展。未来白内障治疗将向手术技术、新型药物和组织工程等方面聚焦，其中白内障手术辅助系统与技术、围手术期干眼管理、干细胞晶状体再生、白内障基因药物以及白内障术后视功能恢复训练等研究，将为白内障治疗提供更加多样化治疗手段。

关键词：屈光性手术晶状体,人工眼外科手术,飞秒激光辅助治疗,白内障

Two Theorems on the Commutativity of Arbitrary Rings

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Acta Mathematica Sinica,English Series 2001年第1期17卷 133-140页

作者： Chang lin fu Xin Song YANG Department of Mathematics Harbin Univrsity of Science and Technology

We prove a theorem on the commutativity of the PI ring and use it to generalize a famous theorem of Herstein.

关键词： PI rings Commutativity Strong property F_k