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A Formula for the Non-integer Powers of the Laplacian

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Acta Mathematica Sinica,English Series 1999年第1期15卷 21-24页

作者： Zhengxu HeDepartment of Mathematics,University of california,San Diego,La Jolla,ca 92093-0112,USA Department of Mathematics University of California San Diego La Jolla USA

We provide an elementary formula for the non-integer powers of the Laplace operator in the Euclidean *** formulas are helpful in establishing the elliptic nature of some pseudo- differential operators arising from the... 详细信息

关键词： Laplacian Power of Laplacian

Gender Roles in the Utilization and Challenges in the Management of Mangrove Forests in casiguran, Aurora, Philippines

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Open Journal of Ecology 2022年第4期12卷 257-270页

作者： Maria Cristina B. cañada Charles R. Velasco Mancy M. Lota Department of Forestry and Environmental Science Aurora State College of Technology Baler Philippines Research and Development Office Aurora State College of Technology Baler Philippines Department of Agriculture and Aquatic Science Aurora State College of Technology Baler Philippines

Mangrove utilization and management were observed done by men and women depending on their needs and priorities in casiguran, Aurora. This study, therefore, tried to investigate the gender roles in the utilization and management of mangrove forests, the existing mangrove management practices and their challenges, and the relationship between gender and mangrove resources management. A mixed-method approach was used and data were obtained through triangulation. Respondents were obtained through snowball sampling and interviewed using a structured questionnaire with a few open-ended questions. Results revealed that the majority of the respondents were women (60.7%) and residents of Brgy. Esteves (52.5%) live within or near the mangrove forest. Mostly married (59%) who were providing food and income for the family. They utilized mangrove woods (58.20%) with an average quantity of less than 10 board feet (34.4%) for cooking (40.2%). Roots were utilized in minimal amounts (2.50%) for mythical, medicine, and cork purposes. Mollusks (93.44%), commonly bivalves (93.4%), were primarily gleaned by women for food consumption (93.4%) and as a source of income (93. 61%). On the other hand, catching of crabs (57.4%) for consumption (56.6%) and as a source of income (14.8%) and catching of fish (31.1%) for consumption (27.9%) were done by men. Both genders were involved in mangrove management practices, although only 65% of them had actual involvement in mangrove planting, 19% in mangrove nursery development and maintenance, and 16% in mangrove plantation maintenance. Challenges in management include low survival rate of planted mangroves (33%), lack of maintenance activity (20%), and lack of funds for mobilization (20%). A chi-square test of independence revealed that both men and women have no significant difference in their involvement in nursery establishment and maintenance, mangrove planting, and plantation management.

关键词： Social Science Gender Roles Utilization and Management Mangrove Forests Mixed-Method Approach Philippines

Shear strength behavior of geotextile/geomembrane interfaces

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Journal of Rock Mechanics and Geotechnical Engineering 2015年第6期7卷 638-645页

作者： Belén M.Bacas Jorge caizal Heinz Konietzky Terrasolum S.L.Geotechnical Engineering Technology Development Center of University of Cantabria(CDTUC) School of Civil Engineering University of Cantabria Geotechnical Institute TU Bergakademie Freiberg

This paper aims to study the shear interaction mechanism of one of the critical geosynthetic interfaces,the geotextile/geomembrane, typically used for lined containment facilities such as landfills. A largedirect shear machine is used to carry out 90 geosynthetic interface tests. The test results show a strainsoftening behavior with a very small dilatancy （〈0.5 mm） and nonlinear failure envelopes at a normalstress range of 25e450 kPa. The influences of the micro-level structure of these geosynthetics on themacro-level interface shear behavior are discussed in detail. This study has generated several practicalrecommendations to help professionals to choose what materials are more adequate. From the threegeotextiles tested, the thermally bonded monofilament exhibits the best interface shear strength underhigh normal stress. For low normal stress, however, needle-punched monofilaments are *** the regular textured geomembranes tested, the space between the asperities is an important *** closer these asperities are, the better the result achieves. For the irregular textured geomembranestested, the nonwoven geotextiles made of monofilaments produce the largest interface shear strength.

关键词： Geotextiles Geomembranes Landfills Fiber length Roughness Shear strength Friction angle

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超声监测联合宫腔镜诊治子宫内膜异常的价值

生殖与避孕 2005年第7期25卷 438-440页

作者：曹云桂孙莹璞郑州大学基础医学院郑州470000 郑州大学一附院生殖医学中心郑州470000

目的:探讨经阴道超声联合宫腔镜诊治子宫内膜异常的价值。方法:经阴道超声记录患者自然月经周期、排卵期内膜厚度、回声、三线征情况。根据内膜情况分为异常组(观察组)和正常组(对照组),进行宫腔镜检查和诊治术,观察术后内膜恢复情况,... 详细信息

目的:探讨经阴道超声联合宫腔镜诊治子宫内膜异常的价值。方法:经阴道超声记录患者自然月经周期、排卵期内膜厚度、回声、三线征情况。根据内膜情况分为异常组(观察组)和正常组(对照组),进行宫腔镜检查和诊治术,观察术后内膜恢复情况,分析治疗后一年内的妊娠率和妊娠结局。结果:观察组40例患者宫腔镜检查结果异常35例,与B超结果符合率87.5%;对照组22例宫腔镜检查结果正常21例,符合率95.45%。观察组中确诊内膜异常者35例,妊娠率48.57%(17/35),对照组确诊为内膜正常者21例,妊娠率71.43%(15/21),P0.05,两组比较差异有显著意义,行宫腔镜检查和诊治术后复查内膜恢复正常者观察组占4096(14/35)。其妊娠率为64.29%(9/14),继续异常组妊娠率38.10%(8/21),两者间无统计学差异。观察组和对照组足月分娩率相比,P>0.05,两组间无差异。内膜厚度<6mm的6例患者中2例妊娠,均有早期先兆流产症状,经保胎治疗,1例足月分娩,1例孕早期流产。结论:超声监测联合宫腔镜有助于诊断子宫内膜病变。子宫内膜厚度≥8mm<16mm、三线征明显且回声均匀对妊娠有利;内膜厚度<6mm仍有妊娠机会,但要及时保胎治疗。

关键词：阴道超声宫腔镜子宫内膜

Modelling ballistic impact on military helmets:The relevance of projectile plasticity

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Defence Technology（防务技术） 2021年第5期17卷 1699-1711页

作者： A.caçoilo R.Mourao F.Teixeira-Dias A.Azevedo F.Coghe R.A.F.Valente School of Engineering The University of EdinburghEdinburghEH93FGUK Dept.Weapon Systems and Ballistics Royal Military AcademyBrusselsBelgium Centre for Mechanical Technology and Automation Department of Mechanical EngineeringUniversity of AveiroPortugal

The need to develop armour systems to protect against attacks from various sources is increasingly a matter of personal,social and national *** develop innovative armour systems it is necessary to monitor developments being made on the type,technology and performance of the threats(weapons,projectiles,explosives,etc.) Specifically,the use of high protection level helmets on the battlefield is *** development of evaluation methods that can predict injuries and trauma is therefore of major ***,the risk of injuries or trauma that can arise from induced accelerations is an additional *** develop new materials and layouts for helmets it is necessary to study the effects caused by ballistic impacts in the human head on various *** use of numerical simulation is a fundamental tool in this *** work here presented focuses on the use of numerical simulation(finite elements analysis) to predict the consequences of bullet impacts on military helmets on human *** main objectives are to assess the level and probability of head trauma using the Head Injury Criterion,caused by the impact of a 9 mm NATO projectile on a PASGT helmet and to quantify the relevance of projectile plasticity on the whole modelling *** accelerations derived from the impact phenomenon and the deformations caused on the helmet are evaluated using fully three-dimensional models of the helmet,head,neck and *** studies are done at impact angles ranging from 0 to 75°.Results are presented and discussed in terms of HIC and probability of acceleration induced trauma *** comparison analyses are done using a rigid and a deformable projectile and it is observed that plastic deformation of the projectile is a significant energy dissipation mechanism in the whole impact process.

关键词： Ballistic impact Helmet impact Plasticity Finite element analysis Injury Trauma HIC

Hydrodynamic and fluid-inclusion studies of base metal mineralization and hydrocarbon systems in the Paleozoic Anticosti and Maritimes basins, eastern canada

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Hydrodynamic and fluid-inclusion studies of base metal miner...

全国包裹体及地质流体学术研讨会

作者： Guoxiang Chi Department of Geology, University of Regina, Regina, SK canada S4S 0A2 E-mail: guoxiang.chi@uregina. ca

＜正＞ The Anticosti Basin, located in the northern part of Gulf of St. Lawrence and centered at Anticosti Island, eastern canada, is an Early Paleozoic marine basin formed in the eastern margin of the Laurentia continent. It constitutes part of the St. Lawrence Platform. The Maritimes Basin, covering much of the southern part of Gulf of St. Lawrence and surrounding onshore areas, is a Late Paleozoic continental successor basin. It is the uppermost tectonic constituent of the Appalachian Orogen. The Anticosti Basin consists of cambrian to Lower Ordovician passive margin sediments and Middle Ordovician to Lower Silurian foreland basin sediments, intervened by the Taconian Orogeny in Middle Ordovician. The Maritimes Basin is filled with Upper Devonian to

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无损电量比重变化对线损率的影响分析

黑龙江电力 2018年第1期40卷 52-54,75页

作者：曹融国网黑龙江省电力有限公司电力科学研究院哈尔滨150030

为了消除无损电量对线损率真实情况的掩盖,剔除无损电量对线损率波动的影响,对无损电量进行了定义,提出了一种无损电量占比对线损率影响的计算方法,用实例计算分析了黑龙江省各个电压等级以及各个地区无损电量占比对线损率的影响。分析... 详细信息

为了消除无损电量对线损率真实情况的掩盖,剔除无损电量对线损率波动的影响,对无损电量进行了定义,提出了一种无损电量占比对线损率影响的计算方法,用实例计算分析了黑龙江省各个电压等级以及各个地区无损电量占比对线损率的影响。分析结果表明:利用提出的方法计算分析黑龙江电网各电压等级与地区的线损率,能够准确计算出受无损电量占比影响后的电网线损率变化值。

关键词：电力系统无损电量线损率占比

On the Equivalence of Multiplicative Structures in Floer Homology and Quantum Homology

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Acta Mathematica Sinica,English Series 1999年第1期15卷 53-80页

作者： Gang LiuDepartment of Mathematics,UCLA,Los Angeles,ca 90095 USAGang TianDepartment of Mathematics,MIT,cambridge,MA 02139,USA Department of Mathematics UCLA Los Angeles USA Department of Mathematics MIT Cambridge USA

In this paper,we will prove that Floer homology equipped with either the intrinsic or exterior product is isomorphic to quantum homology as a *** will also prove that GW-invariants in Floer homology and quantum homolo... 详细信息

关键词： Floer homology Quantum homology GW-invariants J-holomorphic curves Moduli space

HPLC-MS/MS法检测自来水中34种新污染物及健康风险评估

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中国法医学杂志 2024年第1期39卷 31-38页

作者：曹艺璇苑仔薇穆哓茜吕琛山崔海燕王涛尉志文陈中兵邹红艳贠克明胡萌山西医科大学法医学院山西晋中030600 山西法医学重点实验室山西晋中030600 法庭毒物分析公安部重点实验室山西晋中030600 天津师范大学水资源与环境重点实验室天津300387

目的建立了同时检测自来水中34种新污染物(Emerging Contaminants,ECs)的液相色谱-三重四极杆串联质谱(HPLC-MS/MS)方法,并对43个自来水样品进行检测,根据检测结果进行人体健康风险评估。方法样品经固相萃取富集提取后,40℃氮吹至近干,... 详细信息

目的建立了同时检测自来水中34种新污染物(Emerging Contaminants,ECs)的液相色谱-三重四极杆串联质谱(HPLC-MS/MS)方法,并对43个自来水样品进行检测,根据检测结果进行人体健康风险评估。方法样品经固相萃取富集提取后,40℃氮吹至近干,用甲醇-水溶液(95∶5,V/V)复溶至0.5 mL后测定;质谱采用AJS ESI电离源,MRM采集模式。使用标准品建立了34种ECs的母离子、子离子及保留时间的信息库。结果34种ECs在线性范围内平均线性相关系数(r)为0.9959。检出限为0.01~0.60 ng/L,回收率为60.7%~119.8%,批内精密度为0.05%~9.89%,日间精密度为0.20%~14.40%。应用该方法在43个自来水样品中共检出15种物质,其中咖啡因检出率最高(84%),浓度范围为ND~74.42 ng/L;检出浓度最高的ECs是1,2,3-苯并三唑,浓度范围为ND~361.15 ng/L,检出率为44%。人类通过饮用自来水可能存在暴露风险。对其中检出的12种ECs进行了人体健康风险评估,发现统计的ECs风险熵值均0.01。结论该方法操作简单、灵敏度高、选择性强,能满足自来水中痕量ECs的检测需求,且利用该方法对43个自来水样品进行分析,检出的ECs对人体健康均不存在风险。

关键词：法庭环境科学自来水新污染物固相萃取液相色谱-三重四极杆串联质谱健康风险