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Numerical Simulation for Arc Windshields of Aircrafts Subjected to Bird Impact

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上海交通大学学报 2004年第z2期38卷 147-151页

作者： Yao xiaohu Zhao Longmao liu Xiaoming Institute of Applied Mechanics Taiyuan University of Technology China College of Traffic and Communications South China University of Technology China Institute of Applied Mechanics Taiyuan University of Technology China Chengdu Aircraft Industry Company China

A finite element model including full-scale circular arc windshield glass and the relative parts of the military plane is established in this paper. The model is analyzed by using an explicit element code LS-DYNA3D for analyzing the nonlinear dynamic response of structures. The data in aspects of displacement, strain, stress and contact force in the process of deformation are obtained. The deformation and failure mechanism of circular arc windshield glass are discussed. The possible location at which failure may take place is given. The valuable data are provided for designing,researching and producing new windshields with high crashworthiness.

关键词： bird impact arc windshield dynamic response liquid-solid coupling

AN EXPERIMENTAL TECHNIQUE TO MEASURE PROJECTILE DECELERATION HISTORY DURING NORMAL PENETRATION INTO PLAIN CONCRETE

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Acta Mechanica Solida Sinica 2000年第2期13卷 112-118页

作者： liu xiaohu liu Ji Wang Cheng Department of Mechanics Huazhong University of Science and TechnologyWuhan 430074China Xi'an 212 Institute Xi'an 710063China

The present paper presents a new experimental method to measure the deceleration time history of projectiles penetrating into concrete in full-size test. The experiment can be carried out by using an onboard accelerometer to measure the projectile deceleration history and the data are transmitted to a ground recording system. With this experimental method, a series of tests on hemisphere-nose steel projectiles penetrating normally into plain concrete at the velocity region 150 - 400 m/s have been executed and the deceleration histories obtained. The high frequency portion in the deceleration data has been investigated and proved to be the structure response of projectile. The characteristics of deceleration history have also been analyzed and discussed.

关键词： impact test projectile concrete

Dynamic Load Flow Used for Electric Power System State and Tendency Analysis

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哈尔滨工业大学学报 1990年第3期22卷 105-111页

作者： Wang Xianrong Chen xiaohu liu Zhuo (Department of Electrical Engineering)

Dynamic load flow technology can simulate actual frequency and load flow change when a load naturally varies and generator units adjust their power output by an adjustment system during a certain time. Dynamic load flow is a basic part of power system state and tendency analysis. In this paper, a dynamic load flow model and its solution method are first presented and discussed. Then, the application of dynamic load flow to a real power system is given as a demonstration.

关键词：电力系统动载荷流静态分析动态分析电力工业

The structure of mixed-species bird flocks,and their response to anthropogenic disturbance,with special reference to East Asia

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Chinese Birds 2015年第3期6卷 121-131页

作者： Eben Goodale Ping Ding xiaohu liu Ari Martínez Xingfeng Si Mitch Walters Scott K.Robinson Department of Forestry Guangxi University College of Life Sciences Zhejiang University Wildlife Conservation Society China Program Department of Biology San Francisco State University Department of Biology University of Florida Florida Museum of Natural History University of Florida

Mixed-species flocks of birds are distributed world-wide and can be especially dominant in temperate forests during the non-breeding season and in tropical rainforests *** review from a community ecology perspective what is known about the structure and organization of flocks,emphasizing that flocking species tend to be those particularly vulnerable to predation,and flocks tend to be led by species that are able to act as sources of information about predators for other *** on how flocks respond to fragmentation and land-use intensification continue to accumulate,but the question of whether the flock phenomenon makes species more vulnerable to anthropogenic change remains *** review the literature on flocks in East Asia and demonstrate there is a good foundation of knowledge on which to *** then outline potentially fruitful future directions,focusing on studies that can investigate how dependent species are on each other in flocks,and how such interdependencies might affect avian habitat selection in the different types of human-modified environments of this region.

关键词： Biodiversity crisis Biological networks Community assembly Competition Interspecific communication Keystone species Mutualism Pr

Urinary analysis based on surface-enhanced Raman scattering for the noninvasive screening of lung cancer

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Engineered Regeneration 2022年第4期3卷 387-396页

作者： Xueqian Ren Liping Huang Chengde Wang Yuancai Ge Kaili Zhang Danfeng Jiang xiaohu liu Qingwen Zhang Yi Wang School of Biomedical Engineering School of Ophthalmology and OptometryEye HospitalWenzhou Medical UniversityWenzhou 325001China Engineering Research Center of Clinical Functional Materials and Diagnosis&Treatment Devices of Zhejiang Province Wenzhou InstituteUniversity of Chinese Academy of SciencesWenzhou 325001China The First Affiliated Hospital Wenzhou Medical UniversityWenzhou 325001China School of Opto-Electronic Engineering Changchun University of Science and TechnologyChangchun 130022China

We developed a reliable simple analysis of adenosine,creatinine and other nucleosides(cytidine and guanosine)with single measurement based on surface-enhanced Raman spectroscopy(SERS)using DSP-AuNPs with Cu^(2+)ions probe and applied it to achieve noninvasive screening of lung *** gold nanoparticles(AuNPs)were modified with 3,3′-dithiodipropionic acid di(N-hydroxysuccinimide ester)(DSP),which could react with above mentioned molecules followed with the aggregation of AuNPs at the presence of Cu^(2+),thus form the plasmonic hot spots to dramatically increase their fingerprint Raman *** probe of DSP-AuNPs was applied for the detail analysis of urinary adenosine of healthy people and lung cancer *** SERS measurement indicated a higher concentration of urinary adenosine for lung cancer patients than that of healthy people,which was consistent with the results measured by high-performance liquid chromatography(HPLC).In combination of Raman spectroscopy with the orthogonal partial least squares discriminant analysis(OPLS-DA)model,we are able to discriminate the lung cancer patients from healthy people with the urinary *** results indicated that besides of adenosine,other metabolites including uric acid,guanine and creatinine may also be the potential tumor markers in urine for the noninvasive lung cancer *** a method paves a way for the noninvasive cancer screening and it can be further modified for the detection of other molecules on medical diagnosis.

关键词： Adenosine Surface-enhanced Raman scattering Gold nanoparticles OPLS-DA Lung cancer Noninvasive diagnosis

Cell Coverage Estimation Based on Structured Random Forests Edge Detection and Boundary Tracking

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Cell Coverage Estimation Based on Structured Random Forests ...

Experimental Study on Anchoring Physical Properties of Different Anchoring Lengths Coupled with Temperature and Pressure

作者： xiaohu liu School of Intelligent Science ＆ Information Engineering Xi’an Peihua University

To estimate the cell coverage accurately and effectively, an approach based on the structured random forests with mutual information and boundary tracking is proposed. And with the structured random forest, which is improved with mutual information to enhance the mapping function from the structured information to discrete labels, the salient and sematic edges are detected. On the basis of detected edges, the cell contours are found using boundary tracking algorithm. And the experiments imply the effective of the proposed method.

关键词： Edge Detection Boundary Tracking Algorithm Structured Random Forests

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Open Journal of Civil Engineering 2023年第1期13卷 181-191页

作者： Jiaqi Wang Zhishu Yao xiaohu liu Hui Li School of Civil Engineering and Architecture Anhui University of Science and Technology Huainan China

Aiming at deep roadway anchorage solids, laboratory similar model tests were used to reveal the mechanical properties of anchorage solids with different anchorage lengths under the coupling effect of temperature and pressure, and SPSS statistical analysis software was used to conduct linear regression analysis of the ultimate anchorage force obtained from the tests. The results show that: through multiple linear regression analysis, the influence degree of temperature and pressure coupling on the ultimate anchorage force is arranged in order of anchoring length > surrounding rock strength > temperature > side pressure coefficient, and the linear regression equation of the model is obtained. Compared with the linear regression equation of simulation results, the model has a high explanatory ability.

关键词： Temperature-Pressure Coupling Similar Model Test Ultimate Anchorage Force Multiple Linear Regression Analysis

Soil Microbial Population Dynamics along a Chronosequence of Moist Evergreen Broad-leaved Forest Succession in Southwestern China

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Journal of Mountain Science 2010年第4期7卷 327-338页

作者： ZHU Wanze CAI xiaohu liu Xingliang WANG Jinxi CHENG Song ZHANG Xiuyan LI Dengyu LI Maihe Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China Sichuan Academy of Forestry Chengdu 610081 China Siehuan Agricultural University Yaan 625014 China Swiss Federal Research Institute WSL Zuereherstrasse 111 CH-8903 Birrnensdorf Switzerland

Little is known about whether soil microbial population dynamics are correlated with forest *** test the hypotheses that(1) soil microbial composition changes over successional stages,and(2) soil microbial diversity is positively correlated with plant species diversity,we determined the soil microbial populations,community composition,and microflora diversity in evergreen broad-leaved forests along a chronosequence of vegetation succession from 5 to 300 years in southwestern *** soil microbial community was mainly composed of bacteria(87.1-98.7% of the total microorganisms and 10 genera identified),fungi(0.3-4.0%,7 genera),and actinomycetes(2.1-9.1%,8 species and 1 genus).There were significant differences in soil microbial populations among different successional stages and within the four *** seasonal variations of the soil microbial community may be associated with the seasonal changes in environmental *** changes in soil microbial diversity(Shannon-Wiener index) with successional time followed one-humped,convex curves peaked at-100 years since restoration,which is identical with the trends of the aboveground plant *** plant diversity resulting in enhanced nutrient flow and root exudation may contribute to positive relationships between the soil microbial diversity and plant ***,decreases in soil microbial diversity in the late-successional stages appear to be related to the net loss in species richness that occurs after 100 years since *** findings confirm the intermediate disturbance hypothesis that suggests diversity peaks at midsuccessional stages.

关键词： Actinomycetes Bacteria Fungi Microbial diversity Moist evergreen broad-leavedforest Seasonal dynamics

唐代前期军中肉食供给初探--以敦煌吐鲁番军事文书为中心

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敦煌研究 2020年第3期 107-116页

作者：刘啸虎湘潭大学碧泉书院·哲学与历史文化学院湖南湘潭411100

唐前期军中马匹等牲畜死亡后的处置,为剥皮纳库、畜肉出售。出售环节中,军人以象征性低价购买,军外平民则按市价交易。唐代行军中设置临时账房,统兵军官将兵士钱财集中存入,随时支取,向随军商人购买肉食等军需品,军中向士兵放贷的制度... 详细信息

唐前期军中马匹等牲畜死亡后的处置,为剥皮纳库、畜肉出售。出售环节中,军人以象征性低价购买,军外平民则按市价交易。唐代行军中设置临时账房,统兵军官将兵士钱财集中存入,随时支取,向随军商人购买肉食等军需品,军中向士兵放贷的制度亦随之产生。这反映出彼时西州地区商品货币经济的发展水平。

关键词：唐代唐军马肉左憧憙敦煌吐鲁番文书