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damage Symptoms and damage degree of Main Diseases and Pests in Foxtail Millet in Chengde Area

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Plant Diseases and Pests 2018年第1期9卷 12-16页

作者： Fan Qingjie Zhang Yingying Shi Aili Xing Zhanmin Kang Liang Chengde Academy of Agriculture and Forestry Chengde067000

The species of main diseases and pests in foxtail millet and their damage status were investigated in 15 survey points in Longhua, Weichang, Chengde, Fengning and Luanping counties, Chengde City from 2015 to 2017. It was preliminarily cleared that there were 11 species of main diseases and 8 species of pests in continuous cropping millet field. The diseases damaged severely were millet downy mildew and kernel smut, and pests were yellow-legged lema, millet shoot fly and soil insects. The results provided a scientific basis for green control of millet pests and diseases and safe production in Chengde area.

关键词： Chengde area Foxtail millet Diseases and pests damage symptoms damage degree

A New Approach of Multi-degree damage Modal Identification for Motors

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A New Approach of Multi-degree Damage Modal Identification f...

The Performance Evolution Characteristics of Insitu Concrete at the Permafrost Regions

2011 IEEE 2nd International Conference on Computing, Control and Industrial Engineering(CCIE 2011)

作者： Tong Jia College of Electro-mechanics Engineering Jiaxing University JiaXing China

The bearing was the key part of asynchronous motors, and the bearings would be damaged with multi-degree modal from slightly to badly if they were used for a long time. This paper proposed a method for multi-degree damage modal identification of motors based on wavelet and neural networks. the vibration signals of asynchronous motor were considered to be researched, and the feature vectors were extracted by wavelet-packet transform, and the feature vectors were computed as the form of energy spectrum of the wavelet- packet coefficient, and combined with the classifying tool RBF neural networks for identification of many damaged modals of bearings for motors. The experiment results had proofed its’ rationality and validity, and provided a new method for fault analysis and system identification of asynchronous motors.

关键词： asynchronous motors damage degree fault identification wavelet-packet

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Journal of Wuhan University of Technology(Materials Science) 2024年第6期39卷 1534-1540页

作者： NING Zuojun LI Haoxin NIE Kangjun Nueraili Maimaitituersun Aihemaitijiang Tuerhong GAO Xiang School of Transportation Kashi UniversityKashi 844000China KeyLaboratory of Advanced Civil Engineering Materials of Ministry of Education School of Materials Science and EngineeringTongji UniversityShanghai 201804China

This study aimed to investigate the performance evolution characteristics of concrete under permafrost ambient temperatures and to explore methods to mitigate the thermal perturbation by concrete on the permafrost environment.A program was designed to investigate the properties of various concretes at three curing *** compressive strength development pattern of each group was evaluated and the concrete's performance was characterized by compressive strength damage degree,hydration temperature and SEM analysis in a low temperature *** experimental results show that the incorporation of fly ash alone or incombination with other admixtures in concrete under low-temperature curing does not deteriorate its microstructure,and at the same time,it can slow down the hydration rate of cement and significantly reduce the exothermic heat of hydration of *** findings are expected to provide valuable references for the proportioning design of concrete in permafrost environments.

关键词： permafrost ambient mineral admixture compressive strength hydration temperature damage degree

Association of host plant growth and weed occurrence with armyworm(Mythimna separata) damage in corn fields

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Journal of Integrative Agriculture 2018年第7期17卷 1538-1544页

作者： ZHANG Kun-peng YU Zhi-hao JIANG Shi-xiong SUN De-wen HUI Jun-tao ZHENG Yu-liang LI Xiao-zhen WANG Xing-yun WU Jun-xiang State Key Laboratory of Crop Stress Biology in Arid Areas/College of Plant Protection Northwest A&F UniversityYangling 712100P.R.China Anyang Institute of Technology Anyang 455000P.R.China Plant Protection and Quarantine Station of Sanyuan County Sanyuan 713800P.R.China Plant Protection and Quarantine Station of Lantian County Lantian 710500P.R.China Plant Protection and Quarantine Station of Chang'an District Chang'an 710100P.R.China Zhengping Plant Protection Technology Limited Company Xi'an 710000P.R.China

To clarify association between armyworm（Mythimna separata） damage level and the corn growth and weed occurrence, we investigated corn plant height, stem diameter and vigor as well as weed coverage and biomass. The investigations were conducted at three locations of Shaanxi Province, China which were suffered seriously from armyworm. Significant correlations were found between the parameters analyzed. At stunted corn growth and presence of plenty of weeds, the armyworm damage tended to be heavy; oppositely, when corn grew well and weed density were low, armyworm harm was the minimal. Therefore, corn growing status and weed density can significantly affect armyworm damage level. Our results imply that promoting corn growth and timely removal of weeds are conducive to reducing armyworm occurrence.

关键词： Mythimna separata damage degree corn growth corn field weeds

Blasting cumulative damage effects of underground engineering rock mass based on sonic wave measurement

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Journal of Central South University of Technology 2007年第2期14卷 230-235页

作者：闫长斌 School of Resources and Safety Engineering Central South University

The principle of sonic wave measurement was introduced, and cumulative damage effects of underground engineering rock mass under blasting load were studied by in situ test, using RSM-SY5 intelligent sonic wave apparatus. The blasting test was carried out for ten times at some tunnels of Changba Lead-Zinc Mine. The damage depth of surrounding rock caused by old blasting excavation （0.8-1.2 m） was confirmed. The relation between the cumulative damage degree and blast times was obtained. The results show that the sonic velocity decreases gradually with increasing blast times, hut the damage degree （D） increases. The damage cumulative law is non-linear. The damage degree caused by blast decreases with increasing distance, and damage effects become indistinct. The blasting damage of rock mass is anisotropic. The damage degree of rock mass within charging range is maximal. And the more the charge is, the more severe the damage degree of rock mass is. The test results provide references for researches of mechanical parameters of rock mass and dynamic stability analysis of underground chambers.

关键词： sonic wave measurement cumulative damage effects damage degree blasting load surrounding rock of underground engineering RSM-SY5 intelligent sonic wave apparatus

EXPERT SYSTEM FOR COMPREHENSIVE ASSESSMENT TOBRIDGE SERVICE PROPERTY USING FUZZY THEORY

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Journal of Northeast Forestry University 1996年第1期7卷 88-91页

作者：王永平 University of Harbin Architecture and Civil Engineering Harbin China

In this paper, based on consultation to tens of bridge exberts and a vast amount of investigation and study, experts knowledge on bridge assessment has been sorted out. A new concept damage Value (DV) is put forward to measure bridge damage, and Fuzzy theory is used to create comprehensive Fuzzy system to assess bridge service property. The setup of an experts system for bridge assessment is tried as well. This system is programmed in Turbo C 2.0 and has been run successfully at IBM-PC (AT/XT).

关键词： Expert system Bridge performance damage degree Fuzzy evaluation

Equivalent sliding mode fault tolerant control based on hyperbolic tangent function for vertical tail damage

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Journal of Southeast University(English Edition) 2020年第2期36卷 152-162页

作者： Zhuang Huixuan Sun Qingli Chen Zengqian College of Artificial Intelligence Nankai UniversityTianjin 300350China Key Laboratory of Intelligent Robots Nankai UniversityTianjin 300350China

An equivalent sliding mode fault-tolerant control method with continuous switching is proposed for vertical tail ***,the nonlinear damage model of aircraft and the estimation of stability and control derivatives are ***,the linear sliding surface and the equivalent sliding mode controller are constructed,and the sufficient conditions for the stability of the damaged aircraft motion model are given by using the Lyapunov *** damage-tolerant controller is designed based on an adaptive sliding mode control for analyzing damaged aircraft ***,the hyperbolic tangent function is utilized to replace the symbolic function in the *** feasibility of the hyperbolic tangent function as the switching function is analyzed ***,the Boeing-747100/200 model is taken as an example to demonstrate the efficiency of theoretical results by recognizing the structural fault of *** results show that the control law has a positive impact on the performance of the closed-loop system,and it also has a better fault tolerance and robustness towards external disturbance compared with traditional methods of damaged aircraft stabilization control.

关键词： adaptive sliding mode equivalent sliding mode fault tolerant control damaged aircraft damage degree

Invasive sequence and ecological niche of main insect borers of Larix gmelinii forest in Aershan, Inner Mongolia

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Forest Ecosystems 2008年第1期10卷 9-13页

作者： Kari KELIVAARA Department of Applied Biology University of Helsinki FIN-00014 Finland

After the outbreak of Dendrolimus superans Buter in 2002, many insect borers quickly invaded larch (Larix gmelinii Rupr.) forests in the Aershan of Inner Mongolia. Methods involved included setting sample plots, collecting adults in iron traps and measuring areas of galleries to study the invasive sequence, their ecological niche and the extent of the different effects by the main insect borers to their hosts. The results showed that the damage of D. superans weakened L. gmelinii, first Ips subelongatus Motschulsky invaded, followed by Acanthocinus carinulatus Gebler, Monochamus urussovi Fisher and M. sutor L. After the outbreak of D. superans, the average density of longhorn beetles per L. gmelinii tree increased. The ecological niche of Ips subelongatus stretches almost from the base to the top of the trunk. The number of insects in older stands of L. gmelinii is larger than those in middle aged stands. They do not damage healthy trees of L. gmelinii. The ecological niche of A. carinulatus is higher in dead L. gmelinii trees than in weak ones. The degree of damage is directly proportional with age and depth of bark. M. urussovi mainly damages trunks below 4 m in weak trees; in dead trees they can do damage up to 6 m in height. M. sutor mainly damages trunks below 5 m in weak L. gmelinii trees; in dead trees they cause damage up to 7 m. Again, the degree of damage is directly proportional with age. None of the three species of longhorn beetles damage healthy L. gmelinii and younger trees. Among the main insect borers, the degree of damage caused by I. subelongatus is more serious than that of other insects.

关键词： Dendrolimus superans invasive sequence insect borer ecological niche damage degree

damage Tensor Analysis on Regional Seismic Status

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Earthquake Research in China 2006年第3期20卷 339-350页

作者： Zhong Jimao Cheng Wanzheng Earthquake Administration of Fujian Province Fuzhou 350003 China Earthquake Administration of Sichuan Province Chengdu 610041 China

In this paper, we researched the regional seismic status by using theories of the damage Mechanics. The macroscopic damage status of the earth crust block, which is caused by earthquake fracture, is described with several concepts—the damage degree, the damage rate and the strain rate. In the earthquake process, the average strain rate of the studied block is equal to the sum of all seismic moment tensors of the earthquakes taking place in unit time and physical volume. To describe the anisotropy of microdamage of the crust block, we use the damage tensor that is expressed in the fissure density. By means of the transformation from the focal coordinate system to the observation system, we obtained the external normal vector of the focal fault plane expressed in its observation system and obtained the macrodamage degree of the researched block, which is calculated in dyadic. This provides a new analysis method for recognizing the underground damage status and the stress status.

关键词： damage tensor damage degree Earthquake status