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世界潜艇综合声呐系统发展现状及趋势

舰船科学技术 2013年第2期35卷 134-141页

作者：闵瑞红肖杰雄武汉第二船舶设计研究所湖北武汉430064

阐述世界各国海军潜艇自二战以来装备的声呐系统的发展历程。重点介绍美、俄、英、法、德等国现役海军潜艇上装备的综合声呐系统发展现状,包括其技术特点、性能指标和装备情况。并分析世界各国海军潜艇声呐技术的发展方向和发展趋势,提... 详细信息

阐述世界各国海军潜艇自二战以来装备的声呐系统的发展历程。重点介绍美、俄、英、法、德等国现役海军潜艇上装备的综合声呐系统发展现状,包括其技术特点、性能指标和装备情况。并分析世界各国海军潜艇声呐技术的发展方向和发展趋势,提出国外潜艇声呐技术发展对我国的启示。

关键词：潜艇声呐综合声呐系统

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美国海军“海豹”特种作战部队投放系统

舰船科学技术 2012年第1期34卷 138-143页

作者：闵瑞红郭燕舞武汉第二船舶设计研究所湖北武汉430064

作为美国核潜艇重要关键技术之一,输送与回收特种作战部队已成为美国海军高度重视的发展目标。20世纪90年代初期,美国海军提出了先进的"海豹"特种作战部队投放系统(Advanced SEAL Delivery System,ASDS)概念。经过一段时期的研究和论证... 详细信息

作为美国核潜艇重要关键技术之一,输送与回收特种作战部队已成为美国海军高度重视的发展目标。20世纪90年代初期,美国海军提出了先进的"海豹"特种作战部队投放系统(Advanced SEAL Delivery System,ASDS)概念。经过一段时期的研究和论证之后,于1994年正式启动ASDS建造计划。ASDS是一种有人驾驶的"干式"常压微型作战潜器,能在高危环境中隐蔽投放"海豹"特种作战队(Sea-Air-Land Team,SEAL)及其装备,降低队员登陆风险。使SEAL队员在运载过程中处于温暖而干燥的环境中。同时,ASDS可通过潜艇进行部署,性能卓越,在航程、装载量、可靠性、续航力、舒适性和通信/探测能力等方面均具有出色的性能。但由于ASDS在设计上存在致命缺陷,且计划管理不善,致使这项计划在执行了十多年后,最终夭折。本文分析了ASDS的研制背景、计划执行情况及研制过程中存在的问题,以及ASDS计划被取消的原因,较为全面地反映了ASDS计划的整个研制过程。

关键词： ASDS 潜艇美国海军

Gut-brain axis as a bridge in obesity and depression:Mechanistic exploration and therapeutic prospects

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World Journal of Psychiatry 2025年第1期15卷 12-20页

作者： rui-Ying Fang Xiao-rui Pan Xin-Xing Zeng Zheng-Zheng Li Bo-Fan Chen Hai-min Zeng Jie Peng The Second Clinical Medical College The Second Affiliated HospitalJiangxi Medical CollegeNanchang UniversityNanchang 330006Jiangxi ProvinceChina

A recent study by Wang et al,published in the World Journal of Psychiatry,provided preventative and therapeutic strategies for the comorbidity of obesity and *** gut-brain axis,which acts as a two-way communication system between the gastrointestinal tract and the central nervous system,plays a pivotal role in the pathogenesis of these *** suggests that metabolic byproducts,such as short-chain fatty acids,lipopolysaccharide and bile acids,which are generated by the gut microbiota,along with neurotransmitters and inflammatory mediators within the gut-brain axis,modulate the host's metabolic processes,neuronal regulation,and immune responses through diverse *** interaction between obesity and depression via the gut-brain axis involves disruptions in the gut microbiota balance,inflammatory immune responses,and alterations in the neuroendocrine *** the gut-brain axis,for example,through a ketogenic diet,the use of probiotics,and the supplementation of antioxidants,offers new remedial approaches for obesity and *** research that explores the mechanisms of the gut-brain axis is needed to provide more evidence for clinical treatment.

关键词： Gut-brain axis Obesity Depression Gut microbiota Mechanism

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铁矿石物相分析方法的研究与应用

内蒙古石油化工 2018年第11期44卷 27-29页

作者：芮洪敏李娜张程冯婕包钢集团矿山研究院有限责任公司内蒙古包头014010

本文对物相分析方法进行改进,将系统分析法与单项分析法相结合,确定了磁性铁底部圆周研磨选别分离的次数,从而避免磁选不彻底及非磁性物夹杂带来的影响;系统分析法得出硅酸铁与赤褐铁的和量,再与硅酸铁单项分析结果差减得出赤褐铁含量,... 详细信息

本文对物相分析方法进行改进,将系统分析法与单项分析法相结合,确定了磁性铁底部圆周研磨选别分离的次数,从而避免磁选不彻底及非磁性物夹杂带来的影响;系统分析法得出硅酸铁与赤褐铁的和量,再与硅酸铁单项分析结果差减得出赤褐铁含量,从而消除两者不易分离的影响,经验证,该方法测定结果接近标准值,RSD均小于5%,能够满足科研生产检测需要。

关键词：铁矿石影响因素精密度

食品用硅橡胶材料中低摩尔质量环硅氧烷的测定

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塑料工业 2017年第1期45卷 97-100,115页

作者：贺炳慧杨睿田敏于洪观高建国山东科技大学化学与环境工程学院山东青岛266590 清华大学化学工程系北京100084 青岛出入境检验检疫局山东青岛266001

利用红外光谱和STA-GCMS联用仪对市售食品用硅橡胶样品中可能会产生的有毒物质进行定性分析研究。结果显示,在整个升温过程中,样品主要出现了2个失重台阶,分别失重为68.509%和4.377%,对应温度分别为465.96℃和562.15℃。在STA 465℃时,G... 详细信息

利用红外光谱和STA-GCMS联用仪对市售食品用硅橡胶样品中可能会产生的有毒物质进行定性分析研究。结果显示,在整个升温过程中,样品主要出现了2个失重台阶,分别失重为68.509%和4.377%,对应温度分别为465.96℃和562.15℃。在STA 465℃时,GCMS检测到硅橡胶样品释放的主要组份以低摩尔质量的环硅氧烷居多,这与红外光谱分析一致。实验进一步以十二甲基环六硅氧烷为代表,进行正交实验定量分析,初步研究影响其迁移的5种因素,发现影响因素的显著性作用从大到小依次是:模拟液种类>食品模拟液体积>迁移温度>迁移时间>接触面积,这为以后进一步实验奠定了基础。

关键词：气相色谱-质谱红外光谱硅橡胶环硅氧烷

Congruent Feature Selection Method to Improve the Efficacy of Machine Learning-Based Classification in Medical Image Processing

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 357-384页

作者： Mohd Anjum Naoufel Kraiem hong min Ashit Kumar Dutta Yousef Ibrahim Daradkeh Department of Computer Engineering Aligarh Muslim UniversityAligarh202002India College of Computer Science King Khalid UniversityAbha61413Saudi Arabia School of Computing Gachon UniversitySeongnam13120Republic of Korea Department of Computer Science and Information Systems College of Applied SciencesAlMaarefa UniversityRiyadh13713Saudi Arabia Department of Computer Engineering and Information College of Engineering in Wadi AlddawasirPrince Sattam bin Abdulaziz UniversityAl-Kharj16273Saudi Arabia

Machine learning(ML)is increasingly applied for medical image processing with appropriate learning *** applications include analyzing images of various organs,such as the brain,lung,eye,etc.,to identify specific flaws/diseases for *** primary concern of ML applications is the precise selection of flexible image features for pattern detection and region *** of the extracted image features are irrelevant and lead to an increase in computation ***,this article uses an analytical learning paradigm to design a Congruent Feature Selection Method to select the most relevant image *** process trains the learning paradigm using similarity and correlation-based features over different textural intensities and pixel *** similarity between the pixels over the various distribution patterns with high indexes is recommended for disease ***,the correlation based on intensity and distribution is analyzed to improve the feature selection ***,the more congruent pixels are sorted in the descending order of the selection,which identifies better regions than the ***,the learning paradigm is trained using intensity and region-based similarity to maximize the chances of ***,the probability of feature selection,regardless of the textures and medical image patterns,is *** process enhances the performance of ML applications for different medical image *** proposed method improves the accuracy,precision,and training rate by 13.19%,10.69%,and 11.06%,respectively,compared to other models for the selected *** mean error and selection time is also reduced by 12.56%and 13.56%,respectively,compared to the same models and dataset.

关键词： Computer vision feature selection machine learning region detection texture analysis image classification medical images

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基于净资产的证券投资价值评估模型

系统工程理论方法应用 2004年第4期13卷 347-349,354页

作者：李瑞海邹礼瑞陈宏民上海交通大学安泰管理学院上海200052

对证券的价值评估有多种模式,最经典的是现金流模型,但这种模式对很多企业不分红,而股票的价格仍在上升的状况却不能做出很好的解释。另一种是基于市盈率(P/E)预测的股票价值评估,其缺点是基于不断变化的股票价格,且不能反映上市公司的... 详细信息

对证券的价值评估有多种模式,最经典的是现金流模型,但这种模式对很多企业不分红,而股票的价格仍在上升的状况却不能做出很好的解释。另一种是基于市盈率(P/E)预测的股票价值评估,其缺点是基于不断变化的股票价格,且不能反映上市公司的未来盈利能力。本文把股票价值评估用3个指标表示:每股净资产、每股净资产的增长率和投资回报率,并引入合理预期理论介绍股票价格的连续波动,最后通过实证检验了模型在证券市场的应用。该证券价值评估模式能更客观地反映股票投资价值,从而为证券投资活动中的价值判断提供借鉴。

关键词：价值评估净资产股票模型

Stream Surface Strip Element Method and Simulation of Three-Dimensional Deformation of Continuous Hot Rolled Strip

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Journal of Iron and Steel Research International 2004年第2期11卷 18-24页

作者： LIU hong-min WANG Ying-rui Yanshan University

A new method,the stream surface strip element method,for simulating the three-dimensional deformation of plate and strip rolling process was *** rolling deformation zone was divided into a number of stream surface(curved surface)strip elements along metal flow traces,and the stream surface strip elements were mapped into the corresponding plane strip elements for analysis and *** longitudinal distributions of the lateral displacement and the altitudinal displacement of metal were respectively constructed to be a quartic curve and a quadratic curve,of which the lateral distributions were expressed as the third-power spline function,and the altitudinal distributions were fitted in the quadratic *** the flow theory of plastic mechanics,the mathematical models of the three-dimensional deformations and stresses of the deformation zone were *** with the streamline strip element method proposed by the first author of this paper,the stream surface strip element method takes into account the uneven distributions of stresses and deformations along altitudinal direction,and realizes the precise three-dimensional analysis and *** simulation example of continuous hot rolled strip indicates that the method and the model accord with facts and provide a new reliable engineering-computation method for the three-dimensional mechanics simulation of plate and strip rolling process.

关键词： hot-rolling strip plate three-dimensional deformation stream surface strip element method unit rolling pressure friction stress tension stress

Outcomes of 957 preterm neonatal fundus examinations in a Guangzhou NICU through 2008 to 2011

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International Journal of Ophthalmology(English edition) 2012年第4期5卷 469-472页

作者： rui-hong Ju, min Fu Department of Ophthalmology Zhujiang Hospital Southern Medical University Guangzhou 510280 Guangdong Province China Department of Cardiothoracic Surgery Zhujiang Hospital Southern Medical University Guangzhou 510280 Guangdong Province China

AIM: To take fundus examination in the preterm neonates to observe the common diseases and report the outcomes in a neonatal intensive care unit (NICU) in Guangzhou between May 2008 and May 2011. METHODS: Fundus examinations were performed with Retcam II in 957 prematures. RESULTS: There were 957 prematures in this study, including 666 males and 291 females, 2 triple births, 152 twins and 803 singletons. During the three years, 86 infants with any stage retinopathy of prematurity (ROP) (9.0%), 123 infants with retinal hemorrhage (12.9%), 10 infants with neonatal fundual jaundice (1.0%) and 3 babies with congenital choroidal coloboma (0.3%) were found. CONCLUSION: Early detection and prompt treatment of ocular disorders in neonates is important to avoid lifelong visual impairment. Examination of the eyes should be performed in the newborn period and at all well-child visits.

关键词： fundus examination premature retinopathy of prematurity retinal hemorrhage choroidal coloboma early detection