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Journal of Systems Engineering and Electronics 2019年第1期30卷 37-56页

作者： CHANG Tianqing WANG Quandong ZHANG Lei HAO Na DAI Wenjun Department of Weapon and Control Army Academy of Armored Forces center for assessment and demonstration research Academy of Military Sciences Department of Science research Army Academy of Armored Forces

This paper presents the design of an experimental battlefield dynamic scanning and staring imaging system based on a fast steering mirror(FSM), which is capable of real-time monitoring of hot targets and wide-area reconnaissance of hot regions. First,the working principle and working sequence of the FSM are briefly analyzed. The mathematical model of the FSM system is built by modeling its dynamic and electrical properties, and the rationality of the model is validated by means of model identification. Second,the influence of external sources of disturbance such as the carrier and moment on the control precision of the FSM is effectively suppressed by the jointly controlling of proportional integral(PI)and disturbance observer(DOB), thus realizing a high precision and strong robustness control of the FSM system. Then, this paper designs an experimental prototype and introduces a special optical structure to enable the infrared camera to share the FSM with the visible light camera. Finally, the influence of the velocity difference between the mirror of the FSM and the rotating platform on the imaging quality of the system is experimentally analyzed by using the image sharpness evaluation method based on point sharpness. A good dynamic scanning and staring imaging result is achieved when the velocity of these two components correspond.

关键词： fast steering mirror (FSM) dynamic scanning and staring backscanning compensation disturbance observer (DOB) point sharpness.

Investigation on regional attenuation of Vrancea (Romania) intermediate-depth earthquakes

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Earthquake Engineering and Engineering Vibration 2018年第3期17卷 501-509页

作者： Florin Pavel Radu Vacareanu Seismic Risk assessment research center Technical University of Civil Engineering

This paper aims at investigating possible regional attenuation patterns in the case of Vrancea（Romania） intermediate-depth *** 500 pairs of horizontal components recorded during 13 intermediate-depth Vrancea earthquakes are employed in order to evaluate the regional attenuation *** recordings are grouped according to the azimuth with regard to the Vrancea seismic source and subsequently,Q models are computed for each azimuthal zone assuming similar geometrical ***,the local soil amplification which was disregarded in a previous analysis performed for Vrancea intermediate-depth earthquakes is now clearly *** results show minor differences between the four regions situated in front of the Carpathian Mountains and considerable differences in attenuation of seismic waves between the forearc and backarc regions（with regard to the Carpathian Mountains）.Consequently,an average Q model of the type Q（f） = 115×f^1.25 is obtained for the four forearc regions,while a separate Q model of the type Q（f） = 70×f^0.90 is computed for the backarc *** results highlight the need to evaluate the seismic hazard of Romania by using ground motion models which take into account the different attenuation between the forearc/backarc regions.

关键词： Fourier amplitude spectrum azimuth dependency source-to-site distance Q model local soil conditions

Quantitative evaluation of air pollution in transport strategic environmental assessment:a case study based on uncertainty analysis and graphic information system technology

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第5期11卷 370-381页

作者： Hong-tao BAI Hui-zhi WANG He XU Tan ZHU research center for Strategic Environmental assessment Nankai University Tianjin 300071 China

Although the impact of road transport on urban air quality has achieved a high profile in China,still greater attention is required as it has not yet been considered fully even in relation to the road network linking cities and urban areas. Strategic environmental assessment (SEA) is a systematic and comprehensive process for evaluating the environmental impacts of a policy,plan or program in publicly accountable decision-making. Air pollution has been recognized as a significant issue in most transport SEA practices. The Strategic Environmental assessment of the Hubei Road Network Plan (2002-2020) (HRNP) was introduced as one of the World Bank's pilot SEA projects. An effective framework was developed to investigate the functional relationship between the road network and its potential air pollutant emissions. In this study,two indicators were identified:emission intensity/ inventory of pollutants and the spatial distribution of the most polluted areas. Because strategic actions are inherently nebulous and data quality is often disappointing,three alternative scenarios were employed to address uncertainties and data/scale issues. Calculations were made using emission models and results were analyzed with the help of statistical tools and the geographic information system (GIS). The results from the project implementation and the feedback from the World Bank have both shown that the proposed framework is effective in the transport SEA process.

关键词： Air pollution Transport strategic environmental assessment (SEA) Quantitative evaluation Uncertainty

Evaluation of the seismic hazard for 20 cities in Romania using Monte Carlo based simulations

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Earthquake Engineering and Engineering Vibration 2017年第3期16卷 513-523页

作者： Florin Pavel Radu Vacareanu Seismic Risk assessment research center Technical University of Civil Engineering Bucharest Romania

This work focuses on the evaluation of the seismic hazard for Romania using earthquake catalogues generated by a Monte Carlo approach. The seismicity of Romania can be attributed to the Vrancea intermediate-depth seismic source and to 13 other crustal seismic sources. The recurrence times of large magnitude seismic events（both crustal and subcrustal）, as well as the moment release rates are computed using simulated earthquake catalogues. The results show that the largest contribution to the overall moment release for the crustal seismic sources is from the seismic regions in Bulgaria, while the seismic regions in Romania contribute less than 5% of the overall moment release. In addition, the computations show that the moment release rate for the Vrancea subcrustal seismic source is about ten times larger than that of all the crustal seismic sources. Finally, the Monte Carlo approach is used to evaluate the seismic hazard for 20 cities in Romania with populations larger than 100,000 inhabitants. The results show some differences between the seismic hazard values obtained through Monte-Carlo simulation and those in the Romanian seismic design code P100-1/2013, notably for cities situated in the western part of Romania that are influenced by local crustal seismic sources.

关键词： seismic sources uncertainty seismic moment GMPE percentile

Effect of stress ratio on very high cycle fatigue properties of Ti-10V-2Fe-3Al alloy with duplex microstructure

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Journal of Materials Science & Technology 2018年第7期34卷 1189-1195页

作者： Ying Wu Jianrong Liu Hao Wang Shaoxuan Guan Rui Yang Hongfu Xiang Institute of Metal research Chinese Academy of Sciences National demonstration center for Experimental Materials Science and Engineering Education Jiangsu University of Science and Technology

In fatigue critical applications, Ti-10V-2Fe-3Al alloy components are expected to endure cyclic loading with cycles above 109. To assess their operating safety, S-N relations of Ti-10V-2Fe-3Al alloy in very high cycle fatigue （VHCF） regime are of concern and have been investigated in this work. Fatigue behavior including S-N curves and crack initiation mechanisms is reported. Two transitions of fatigue crack initi- ation mechanism, from internal crack initiation to surface crack initiation and from αp cleavage to αS/β decohesion, occur when the stress ratio （R） and stress level are reduced. Fatigue limits exist at Nr = 6×10^7 cycles for all stress ratios except for 0.5. In the VHCF regime two kinds of internal crack initiation mechanisms exist, i.e., coalescence of cluster of αp facets and αS/β decohesion. Their mutual competition depends on the stress ratio and can be interpreted in terms of different stress character required for promotion on different internal crack initiation mechanism. Small crack propagation is discussed to be life controlling process under the stress ratio range from -0.5 to 0.1 during VHCF regime while under the stress ratio 0.5 VHCF, life almost refers to the life required for crack initiation.2017 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science ＆ Technology.

关键词： Ti-10V-2Fe-3Al alloy Very high cycle fatigue S-N curve Fatigue crack initiation Life controlling process

Optimized Methods for the Quantitative Analysis and Modeling of Weapon System’s Testability Indicators

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Optimized Methods for the Quantitative Analysis and Modeling...

Gut microbiota-bile acid crosstalk and metabolic fatty liver in spotted seabass(Lateolabrax maculatus): The role of a cholesterol, taurine and glycine supplement

第32届中国控制与决策会议

作者： XIE Zongren GENG Kui LIU Yi LIU Qiong Academy of Military Science Center of Assessment and Demonstration Research

At present,the quantitative analysis and modeling of testability indicators are rarely *** paper presents the quantitative analysis on equipment testability indicators by combining the similarity model and empirical estimation in the theory of analogy,and builds the comprehensive calculation model for testability indicators based on the Markov ***,it explores the methods for quantitative modeling and determination of such testability indicators as fault coverage rate and fault *** calculations are conducted to analyze the stages and situations to which these methods are applicable within the life cycle of equipment,so as to provide the methodological support and theoretical basis for the research and development,general design and combat application of weapon system.

关键词： weapon system testability quantitative requirements theory of analogy Markov model fault coverage rate

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Animal Nutrition 2024年第2期17卷 87-99页

作者： Tingting Song Xiaofang Liang Hao Wang Min Xue Jie Wang National Aquafeed Safety assessment center Institute of Feed Research Chinese Academy of Agricultural Sciences

The prevalent practice of substituting fishmeal with plant protein frequently leads to disturbances in bile acid metabolism, subsequently increasing the incidence of metabolic liver diseases. Bile acid nutrients such as cholesterol, taurine and glycine have been shown to enhance bile acid synthesis and confer beneficial effects on growth. Therefore, this study aimed to investigate the effects of cholesterol-taurineglycine(Ch-Tau-Gly) supplement on bile acid metabolism and liver health in spotted seabass(Lateolabrax maculatus) fed a plant-based diet. Two isonitrogenous and isolipidic diets were formulated:(1) plant protein-based diet(PP);(2) PP supplemented 0.5% cholesterol, 0.5% taurine and 1.3% glycine(CTG). Each experimental diet was randomly fed to quadruplicate groups of 30 feed-trained spotted seabass in each tank. The results revealed that supplementing plant-based diet with Ch-Tau-Gly supplement led to an increase in carcass ratio(meat yield) in spotted seabass(P < 0.05), indirectly contributing positively to their growth. The dietary supplement effectively suppressed endogenous cholesterol synthesis in the liver, promoted the expression of bile acid synthesis enzyme synthesis, and simultaneously the expression of intestinal fxr and its downstream genes, including hnf4a and shp(P < 0.05). The reduction in Lactobacillus＿salivarius and bile salt hydrolase(BSH) were observed in CTG group with concurrently increased conjugated chenodeoxycholic acid(CDCA) bile acids(P < 0.05), suggesting the enhancement of the hydrophilicity of the bile acid pool. In CTG group, fatty liver was alleviated with a corresponding increase in lipid metabolism, characterized by a downregulation of genes associated with lipogenesis and lipid droplet deposition, along with an upregulation of genes related to lipolysis. Our study underscored the ability of Ch-Tau-Gly supplement to influence the gut microbiota, leading to an increase in the levels of conjugated CDCA(P < 0.05) in the bile aci

关键词： Cholesterol-taurine-glycine supplement Plant-based diets Fatty liver Gut microbiota-bile acid crosstalk Lipid metabolism

Temporal dynamics of neonatal hypoxic-ischemic encephalopathy injuries on magnetic resonance imaging

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Neural Regeneration research 2025年第11期20卷 3144-3150页

作者： Holly Flyger Samantha J.Holdsworth Alistair J.Gunn Laura Bennet Hamid Abbasi Mātai Medical research Institute Tairāwhiti GisborneNew Zealand Department of Anatomy&Medical Imaging Faculty of Medical and Health SciencesThe University of AucklandAucklandNew Zealand center for Brain research The University of AucklandAucklandNew Zealand Auckland Bioengineering Institute The University of AucklandAucklandNew Zealand

Moderate to severe perinatal hypoxic-ischemic encephalopathy occurs in~1 to 3/1000 live births in high-income countries and is associated with a significant risk of death or neurodevelopmental *** assessment is important to help identify highrisk infants,to help families,and to support appropriate interventions.A wide range of monitoring tools is available to assess changes over time,including urine and blood biomarkers,neurological examination,and *** present,magnetic resonance imaging is unique as although it is expensive and not suited to monitoring the early evolution of hypoxic-ischemic encephalopathy by a week of life it can provide direct insight into the anatomical changes in the brain after hypoxic-ischemic encephalopathy and so offers strong prognostic information on the long-term outcome after hypoxic-ischemic *** review investigated the temporal dynamics of neonatal hypoxic-ischemic encephalopathy injuries,with a particular emphasis on exploring the correlation between the prognostic implications of magnetic resonance imaging scans in the first week of life and their relationship to long-term outcome prediction,particularly for infants treated with therapeutic hypothermia.A comprehensive literature search,from 2016 to 2024,identified 20 pertinent *** review highlights that while the optimal timing of magnetic resonance imaging scans is not clear,overall,it suggests that magnetic resonance imaging within the first week of life provides strong prognostic *** challenges limit the timing consistency,particularly the need for intensive care and clinical ***,although most reports examined the prognostic value of scans taken between 4 and 10 days after birth,there is evidence from small numbers of cases that,at times,brain injury may continue to evolve for weeks after *** suggests that in the future it will be important to explore a wider range of times after hypo

关键词： magnetic resonance imaging neonatal hypoxic-ischemic encephalopathy neurodevelopmental outcomes prognostic biomarkers in neuroimaging scan timing therapeutic hypothermia

Current issues and future perspectives of gastric cancer screening

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World Journal of Gastroenterology 2014年第38期20卷 13767-13774页

作者： Chisato Hamashima Cancer Screening assessment and Management Division Research Center for Cancer Prevention and ScreeningNational Cancer Center

Gastric cancer remains the second leading cause of cancer death worldwide. About half of the incidence of gastric cancer is observed in East Asian countries, which show a higher mortality than other countries. The effectiveness of 3 new gastric cancer screening techniques, namely, upper gastrointestinal endoscopy, serological testing, and “screen and treat” method were extensively reviewed. Moreover, the phases of development for cancer screening were analyzed on the basis of the biomarker development road map. Several observational studies have reported the effectiveness of endoscopic screening in reducing mortality from gastric cancer. On the other hand, serologic testing has mainly been used for targeting the high-risk group for gastric cancer. To date, the effectiveness of new techniques for gastric cancer screening has remained limited. However, endoscopic screening is presently in the last trial phase of development before their introduction to population-based screening. To effectively introduce new techniques for gastric cancer screening in a community, incidence and mortality reduction from gastric cancer must be initially and thoroughly evaluated by conducting reliable studies. In addition to effectiveness evaluation, the balance of benefits and harms must be carefully assessed before introducing these new techniques for population-based screening.

关键词： Gastric cancer screening Mortality Upper gastrointestinal endoscopy Upper gastrointestinal X-ray Serum pepsinogen test Helicobacter pylori antibody