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Defence Technology（防务技术） 2020年第1期16卷 88-95页

作者： Song Cai Chen-lei Huang Kun liu zhong-xin Li zhi-lin Wu School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094JiangsuChina

The cartridge case headspace is the axial clearance between the cartridge and bolt of an automatic weapon,and influences the reliability and security of the ***,theoretical and numerical studies were conducted to analyze the dynamic response of cartridge cases during internal impact considering the initial radial clearances between the cartridge case and chamber.A theoretical model was proposed to predict the cartridge case headspace considering both the deformation and movement of the cartridge case and confirmed by the results of nonlinear finite element *** differences between the results of the conventional static model and the dynamic model were then comprehensively *** effects of the angle between the cartridge and chamber,the cartridge case material,and the intermal impact pressure on the predicted headspace value were also *** dynamic response of the cartridge case predicted by the dynamic model was more accurate than that predicted by the conventional static *** internal impact pressure,pressure change rate,and cartridge material were all found to affect the predicted headspace.

关键词： Cartridge case headspace Radial clearance Thick-walled cylinder Dynamic response

Mining Design Pattern Use Scenarios and Related Design Pattern Pairs:A Case Study on Online Posts

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Journal of Computer Science & Technology 2020年第5期35卷 963-978页

作者： Dong liu zhi-Lei Ren zhong-Tian Long Guo-Jun Gao He Jiang School of Software Dalian University of TechnologyDalian 116024China Key Laboratory for Ubiquitous Network and Service Software of Liaoning Province Dalian 116000China DUT-RU International School of Information Science&Engineering at DUT Dalian University of Technology Dalian 116620China

In common design pattern collections,e.g.,design pattern books,design patterns are documented with templates that consist of multiple attributes,such as intent,structure,and sample *** adapt to modern developers,the depictions of design patterns,especially some specific attributes,should advance with the current programming technologies,for example,“known uses”,which exemplifies the use scenarios of design patterns in practice,and“related patterns”,which describes the relatedness between a design pattern and the others within a ***,it is not easy to update the contents of these attributes manually due to the diversity of the programming *** address this problem,in this work,we conducted a case study to mine design pattern use scenarios and related design pattern pairs from Stack Overflow posts to enrich the two *** first extracted the question posts relevant to each design pattern by identifying the design pattern ***,the topics of the posts were discovered by applying topic modeling ***,by analyzing the topics specified for each design pattern,we detected 195 design pattern use scenarios and 70 related design pattern pairs,involving 61 design patterns *** findings are associated with a variety of popular software frameworks and programming *** could complement the existing design pattern collections and help developers better acknowledge the usage and relatedness of design patterns in today's programming practice.

关键词： design pattern software documentation Stack Overflow topic model

Permafrost degradation along the Qinghai-Tibet Highway from 1995 to 2020

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Advances in Climate Change Research 2023年第2期14卷 248-254页

作者： zhi-zhong SUN Wei MA Gui-Long WU Yong-zhi liu Guo-Yu LI State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Da Xing'anling Observation and Research Station of Frozen Ground Engineering and Environment Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesJagdaqi 165000China Beiluhe Observation and Research Station on Frozen Soil Engineering and Environment in QinghaieTibet Plateau Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesGeermu 816000China

Permafrost degradation significantly affects engineering infrastructure,hydrologic processes,landscape and geomorphic processes,ecosystems and carbon cycling in cold *** permafrost degradation along the Qinghai–Tibet Highway(QTH)on the Qinghai–Tibet Plateau,China,introduces an adverse effect on the deformation of the highway *** present,observation of a long series of ground temperatures is *** 1995 to 2020,a monitoring system of ground temperature in 10 natural sites along QTH was built and *** temperatures at different depths were continuously observed *** this study,permafrost changes along QTH were quantitatively investigated based on these *** main results showed that both the permafrost table depth(PTD)and ground temperature at different depths exhibited an increasing trend from 1995 to 2020 with widespread spatiotemporal *** higher the annual mean and range of PTD were,the higher the increase rate in *** increase rates in PTDs in the warm permafrost regions were 6.18 cm per year larger than those in the cold ***,the increase rates in ground temperature decreased with the increase in depth at each *** different depths,the smaller the mean annual ground temperature(MAGT)was,the larger the increase rate in the permafrost *** larger the range of ground temperatures was,the bigger the increase rate in the permafrost *** a depth of 6.0 m,the increase rate in the ground temperature in cold permafrost regions was twice that in warm permafrost *** on the magnitudes and differences in permafrost degradation along QTH is necessary for the design of effective adaption strategies for engineering construction and environment protection in permafrost regions under climatic warming.

关键词： Permafrost table depth Permafrost temperature Permafrost degradation Qinghai-Tibet Highway Qinghai-Tibet Plateau

Interconnections between diabetic corneal neuropathy and diabetic retinopathy:diagnostic and therapeutic implications

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Neural Regeneration Research 2025年第8期20卷 2169-2180页

作者： Mingyi Yu Faith Teo En Ning Chang liu Yu-Chi liu Tissue Engineering and Stem Cell Group Singapore Eye Research InstituteSingapore Yong Loo Lin School of Medicine National University of SingaporeSingapore Department of Cornea and External Eye Disease Singapore National Eye CenterSingapore Ophthalmology and Visual Sciences Academic Clinical Program Duke-NUS Medical SchoolSingapore

Diabetic corneal neuropathy and diabetic retinopathy are ocular complications occurring in the context of diabetes *** corneal neuropathy refers to the progressive damage of corneal *** retinopathy has traditionally been considered as damage to the retinal ***,growing evidence suggests that diabetic retinopathy is a complex neurovascular disorder resulting from dysfunction of the neurovascular unit,which includes both the retinal vascular structures and neural *** retinopathy is one of the leading causes of blindness and is frequently screened for as part of diabetic ocular ***,diabetic corneal neuropathy is commonly overlooked and underdiagnosed,leading to severe ocular surface *** studies have found that these two conditions tend to occur together,and they share similarities in their pathogenesis pathways,being triggered by a status of chronic *** review aims to discuss the interconnection between diabetic corneal neuropathy and diabetic retinopathy,whether diabetic corneal neuropathy precedes diabetic retinopathy,as well as the relation between the stage of diabetic retinopathy and the severity of corneal *** also endeavor to explore the relevance of a corneal screening in diabetic eyes and the possibility of using corneal nerve measurements to monitor the progression of diabetic retinopathy.

关键词： cornea corneal nerves diabetes diabetic corneal neuropathy diabetic retinopathy retina

Relationship of Somatic Cell Count with Milk Yield and Composition in Chinese Holstein Population

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Agricultural Sciences in China 2010年第10期9卷 1492-1496页

作者： GUO Jia-zhong liu Xiao-lin XU A-juan XIA zhi College of Animal Science and Technology Shaanxi Key Laboratory of Molecular Biology for Agriculture Northwest A＆F University Yangling 712100 P.R.China

The objective of this study was to analyze the relationship of somatic cell count （SCC） with milk yield, fat and protein percentage, fat and protein yield using analysis of variance and correlation analysis in Chinese Holstein population. The 10 524 test-day records of 568 Chinese Holstein Cattle were obtained from 2 commercial herds in Xi＇an region of China during February 2002 to March 2009. Milk yield, fat percentage, fat and protein yield initially increased and then dropped down with parity, whereas protein percentage decreased and SCC increased. Analysis of variance showed highly significant effects of different subclasses SCC on milk yield and composition （P〈 0.01）. Compared with milk yield with SCC ≤ 200 000 cells mL-1, milk yield losses with SCC of 200 000-500 000 cells mL-1, 501000-1 000 000 cells mL-1, ≥ 1 000 000 cells mL-1 were 0.387, 0.961 and 2.351 kg, respectively. The highly significant negative correlation coefficient between somatic cell score （SCS） and milk and protein yield, milk yield and fat and protein percentage, protein percentage and fat yield were -0.084, -0.037, -0.061, -0.168, and -0.088, respectively （P〈 0.01）. The highly significant positive correlation coefficients between SCS and fat yield and fat and protein percentage, milk yield and fat and protein yield, fat percentage and protein percentage and fat yield, protein yield and protein percentage and fat yield were 0.041, 0.177, 0.105, 0.771, 0.865, 0.122, 0.568, 0.318, and 0.695, respectively （P〈 0.01）. There was no significant relationship between fat percentage and protein yield （P 〉 0.05）. The results of the present study first time provide the relevant base-line data for assessing milk production at Xi＇an region of China.

关键词： Holstein cattle milk yield milk composition somatic cell count somatic cell score

Systemic Nuclear Proteomics Researches on Change of Jurkat T Lymphocyte Cells Under Radiation

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Chemical Research in Chinese Universities 2010年第5期26卷 717-722页

作者： LIANG Feng liu zhong-ying liu Ning SONG Feng-rui ZHANG Xuan liu zhi-qiang College of Pharmacy Jilin University Changehun 130021 P. R. China Changchun Center of Mass Spectrometry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China Research Center for Genomic Medicine and MH Radiobiology Research Unit School of Public Health Jilin University Changchun 130021 P. R. China

Radiation causes severe constraint on numerous pathological functions of cells, such as cell growth, nuclear genetic material expression and cell functions. In this study, we performed proteomic profiling of a nuclear fraction of Jurkat T lymphocyte cells under radiation along different time course by means of 2DE and MALDI TOF-MS. We found 24 protein spots whose expression had changed after radiation, including relevant proteins, genetic material proteins, metabolism proteins, molecular chaperon and nuclear membrane proteins. Based on the above it is concluded that the combination of fluorescence labeled 2D-PAGE and MALDI-TOF MS is more precisely and effectively to elucidate the protein changes in Jurkat T lymphocyte cells after irradiation.

关键词： Nuclear proteome Two-dimensional difference gel electrophoresis MALDI-TOF-MS Jurkat cell

Coating process of multi-material composite sand mold 3D printing

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China Foundry 2017年第6期14卷 498-505页

作者： zhong-de Shan zhi Guo Dong Du Feng liu China Academy of Machinery Science & Technology Beijing 100044 China Department of Mechanical Engineering Tsinghua University Beijing 100084 China

Sand mold 3 D printing technology is an advanced manufacturing technology which has great flexible manufacturing ability. A multi-material composite sand mold can control the temperature field of metallic parts during the pouring process, while the current sand mold 3 D printing technology can only fabricate a single material sand mold. The casting temperature field can not be adjusted by using single sand mold material with isotropous heat exchange ability during the pouring process. In this work, a kind of novel coating device was designed. Multi-material composite sand molds could be manufactured using the coating device according to the casting process demands of the final parts. The influences of curing agent content, coating velocity and scraper shape on compactness and surface roughness of the sand layer(silica sand and zircon sand) were studied. The shapes and sizes of transition intervals of two kinds of sand granules were also tested. The results show that, with the increase of the added volume of curing agent, the compactness of sand layer reduces and the surface roughness value rises. With the increase of the velocity of the coating device, the compactness of sand layer reduces and the surface roughness value rises similarly. In addition, the scraper with a dip angle of 72 degrees could increase the compactness value of the sand layer. The criteria of quality parmeters of the coating procedure are obtained. That is, the surface roughness(δ) of sand layer should be equal to or lesser than half of main size of the sand particles(Dm). The parameter H of the coating device which is the distance between the base of hopper and the surface of sand layer impacts the size of transition zone. The width of the transition zone is in direct proportion to the parameter H, qualitatively. Through the optimization of the coating device, high quality of multi-material sand layers can be obtained. This will provide a solution in manufacturing the multi-material composite s

关键词： multi-material composite sand mold 3D printing coating process self-adaption coating device

Acidity and conductivity of Pinus massoniana bark as indicators to atmospheric acid deposition in Guangdong, China

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Journal of Environmental Sciences 2006年第5期18卷 916-920页

作者： KUANG Yuan-wen ZHOU Guo-yi WEN Da-zhi liu Shi-zhong Institute of Ecology South China Botanical Garden＇ Chinese Academy of Sciences Guangzhou 510650 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

Barks of Pinus massoniana collected from two polluted sites, Qujiang and Xiqiaoshan, and from the relatively clean site Dinghushan were used to evaluate the pollution indication by the determination of their acidity and conductivity. The acidity of the inner and outer barks from the polluted sites was significantly higher than those from the clean site, suggesting that the acidity of the bark occurred in concurrent with the air pollution. The significant lower pH values of the outer bark than the inner bark collected from all sites indicated that the outer bark was more sensitive than the inner bark in response to acid pollution, implying that the outer bark is more preferable when used as indication of atmospheric acid pollution. The conductivities of the inner barks differed significantly among the three sites, with higher values at the clean site. However, the significant differences were not observed among these sites. Furthermore, the pH values for the inner and outer barks were not correlated with the conductivity, which did not coincide with some other studies.

关键词： acidity conductivity inner bark outer bark Pinus massoniana

ID effects on beam dynamics in the SSRF-U storage ring

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Nuclear Science and Techniques 2023年第11期34卷 140-154页

作者： Li‑Yuan Tan Shun‑Qiang Tian Xin‑zhong liu Xu Wu Wen‑zhi Zhang Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China

This paper introduces the proposed insertion device(ID)scheme for the Shanghai Synchrotron Radiation Facility *** on this scheme,the influences of the ID radiation on the intra-beam scattering emittance and energy spread were *** distortion caused by the IDs was comprehensively examined and compensated using both local and global ***,a frequency map analysis method was used to identify potentially dangerous resonance *** addition,the dynamic aperture,energy acceptance,and Touschek lifetime were calculated after considering high-order magnetic field errors to ensure that the ID effect did not affect the operation of the storage ring.

关键词： SSRF-U Insertion devices Emittance Beam dynamic

Strain concentration caused by the closed end contributes to cartridge case failure at the bottom

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Defence Technology（防务技术） 2020年第6期16卷 1151-1159页

作者： Song Cai Jie Feng Hui Xu Kun liu zhong-xin Li zhi-lin Wu School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094JiangsuChina

Ruptures at the bottom of cartridges are a common cause of failure of ammunitions,which directly threatens the safety of weapons and *** on plastic tube theory,this study analyses the radial and axial deformation of a cartridge,considering the radial constraint of the closed end at the bottom of the *** to the influence of the closed end,the bottom of a cartridge does not establish complete contact with the *** to strain concentration in the non-contact area,this area is more amenable to the occurrence of cartridge *** theory predicts the location of the fracture more accurately than the traditional *** maximum axial deformation of a cartridge comprises bending and friction *** maximum strain at the bottom of the cartridge increased by 135%owing to the introduction of bending strain caused by the closed *** strain distribution of a cartridge was measured using digital image correlation technology,and the measured result was consistent with the predicted results of the bending deformation theory and rupture *** effects of wall thickness,radial clearance,friction coefficient,and axial clearance on the axial deformation of the cylinder were *** the wall thickness and reducing radial clearance were found to reduce bending deformation;furthermore,lubrication and reduction in axial clearance reduce frictional deformation,which in turn reduce cartridge rupture.

关键词： Closed end Cartridge case failures Strain concentration Bending deformation