期刊文献+
共找到524篇文章
< 1 2 27 >
每页显示 20 50 100
Resilience and response:Unveiling the impacts of extreme droughts on forests through integrated dendrochronological and remote sensing analyses 被引量:1
1
作者 Han Shi Xi Peng +6 位作者 Yong-Jiao Zhou Ai-Ying Wang Xue-Kai Sun Na Li Quan-Sheng Bao Gude Buri Guang-You Hao 《Forest Ecosystems》 SCIE CSCD 2024年第4期491-501,共11页
Extreme droughts are anticipated to have detrimental impacts on forest ecosystems,especially in water-limited regions,due to the influence of climate change.However,considerable uncertainty remains regarding the patte... Extreme droughts are anticipated to have detrimental impacts on forest ecosystems,especially in water-limited regions,due to the influence of climate change.However,considerable uncertainty remains regarding the patterns in species-specific responses to extreme droughts.Here,we conducted a study integrating dendrochronology and remote sensing methods to investigate the mosaic-distributed maple-oak(native)natural forests and poplar plantations(introduced)in the Horqin Sandy Land,Northeast China.We assessed the impacts of extreme droughts on tree performances by measuring interannual variations in radial growth and vegetation index.The results showed that precipitation and self-calibrated palmer drought severity index(scPDSI)are the major factors influencing tree-ring width index(RWI)and normalized difference vegetation index(NDVI).The severe droughts between 2000 and 2004 resulted in reduced RWI in the three studied tree species as well as led to NDVI reductions in both the maple-oak natural forests and the poplar plantations.The RWI reached the nadir during the2000-2004 severe droughts and remained at low levels two years after the severe drought,creating a legacy effect.In contrast to the lack of significant correlation between RWI and scPDSI,NDVI exhibited a significant positive correlation with scPDSI indicating the greater sensitivity of canopy performance to droughts than radial growth.Furthermore,interspecific differences in RWI and NDVI responses were observed,with the fast-growing poplar species experiencing a more significant RWI decrease and more negative NDVI anomaly during severe droughts than native species,highlighting the species-specific trade-offs between drought resilience and growth rate.This study emphasizes the importance of combining tree-level radial growth with landscape-scale canopy remote sensing to understand forest resilience and response.Our study improves our understanding of forest responses to extreme drought and highlights species differences in climate responses,offering crucial insights for optimizing species selection in sustainable afforestation and forest management in water-limited regions under the influence of climate change. 展开更多
关键词 Introduced tree species Native tree species NDVI Severe drought Tree-ring width
下载PDF
Endophytic Occupation in Nodules of Rhynchosia Plants from Semiarid Regions of Argentina
2
作者 Cinthia T.Lucero María de los Á.Ruíz +3 位作者 Fabiola Pagliero Carolina Castaño Mariela L.Ambrosino Graciela S.Lorda 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第6期1081-1099,共19页
Beneficial microbes can improve soil health by promoting soil structure,nutrient cycling,and disease suppression.In addition,a wide array of rhizospheric microbes are responsible for producing metabolically active comp... Beneficial microbes can improve soil health by promoting soil structure,nutrient cycling,and disease suppression.In addition,a wide array of rhizospheric microbes are responsible for producing metabolically active compounds including various types of plant growth regulators.So,microbial biodiversity studies could contribute to the improvement of agricultural practices in deprived areas,such as the Pampean semiarid region.The vast majority of studies conducted on endophytic microorganisms have focused on intensive crop legume species.In contrast,little attention has been paid to microorganisms of native legumes,whose ecology is not directly affected by human action.In this study,endophytic microorganisms isolated from root nodules of a selected native legume of the genus Rhynchosia were characterized.Viable isolates were studied with a focus on their plant growth-pro-moting rhizobacteria(PGPR)properties.Considering the edaphic characteristics of the Pampean semiarid region,the isolates obtained were evaluated for their ability to grow under three salt stress conditions(50,100,and 200 mM NaCl)and four different pH values(6,7,8,and 9).Based on their PGPR activities,the selected strains were phylogenetically grouped using BOX-PCR.The results showed great variability among the isolates in terms of the characteristics studied.Native legumes manifested a wide endophytic variability and remarkable perfor-mance in PGPR activities.We conclude that they could be used as potential bioinoculants for legume cultivation,an excellent alternative to the use of chemical fertilizers that currently pollute the environment. 展开更多
关键词 Native strains ENDOPHYTES PGPR native legumes stress
下载PDF
Prospects and limitations of soil amendment and irrigation techniques for the water-saving public urban greenery and ephemeral weed management in the sandy soils of the United Arab Emirates
3
作者 Ayesha ALAM Elke GABRIEL-NEUMANN 《Journal of Arid Land》 SCIE CSCD 2024年第9期1288-1302,共15页
Public urban greenery greatly contributes to the residential and tourist value of cities in the Gulf Region,but due to the hyper-arid climatic conditions,the cost of irrigation and plant maintenance is very high.Exist... Public urban greenery greatly contributes to the residential and tourist value of cities in the Gulf Region,but due to the hyper-arid climatic conditions,the cost of irrigation and plant maintenance is very high.Existing strategies to reduce the monetary and ecological costs involve the cultivation of native xerophytic plantations,and/or the use of soil improvers to increase water-and nutrient-holding capacity of the sandy soils.Various soil improvers based on mineral,organic,or synthetic materials have entered the United Arab Emirates(UAE)market in recent years,but there is considerable uncertainty about how they should best be used in combination with ornamental plant stands involving xerophytic native plants.The present study investigated the effect of soil amendment and deep pipe irrigation on perennial ornamental plant stands involving native plants(Tephrosia appolinea(Gel.)Link in combination with Aerva javanica(Burm.f.)Juss.ex Schult.)and native-exotic plants(T.appolinea in combination with Ruelia simplex C.Wright)either or not topsoil and subsoil amendment with bentonite and hydrophobic sand under the irrigation water supply of less than 50%of reference evapotranspiration(ET0).After one year of cultivation,T.appolinea and A.javanica(native vs.native)produced high biomass and exhibited high water use efficiency(WUE)as compared with T.appolinea and R.simplex(native vs.exotic)combination given that no significant differences were found under the soil amendment treatments.All stands thrived under irrigation water supply far below what is usually supplied to exotic ornamental stands in public parks of the Al Ain City,the UAE.However,subsoil amendment in combination with deep pipe irrigation reduced the occurrence of weeds and increased the overall plant rooting depth.Our results suggest that subsoil amendment and irrigation up to 60-80 cm depth can potentially control ephemeral weed infestation,which is a great challenge in various plant production systems of the Gulf Region.The results of the present study suggest that the impact of soil amendment on the WUE of exotic plants is marginal and might not be economically justified.Replacing exotic with native ornamental plant species seems to have a far greater water-saving potential than the amendment of the soil,while weeds can be suppressed in the absence of topsoil moisture. 展开更多
关键词 native and exotic plant communities competitive strength soil improvers urban plantation subsoil amendment weed management
下载PDF
Geochemistry, mineral paragenesis and geothermal conditions of oreforming fluids from the Ain El Bey Cu–Fe deposit: potential occurrence of native gold and precious metal traces (North African orogenic belt, Northern Tunisia)
4
作者 Rania Ben Aissa Wiem Ben Aissa +2 位作者 Said Tlig Lassaad Ben Aissa Abdessalem Ben Haj Amara 《Acta Geochimica》 EI CAS CSCD 2024年第2期366-384,共19页
The Ain El Bey abandoned mine, in North-West Tunisia, fits into the geodynamic context of the European and African plate boundary. Ore deposit corresponds to veins and breccia of multiphase Cu–Fe-rich mineralization ... The Ain El Bey abandoned mine, in North-West Tunisia, fits into the geodynamic context of the European and African plate boundary. Ore deposit corresponds to veins and breccia of multiphase Cu–Fe-rich mineralization related to various hydrothermal fluid circulations. Petromineralogical studies indicate a rich mineral paragenesis with a minimum of seven mineralization phases and, at least, six pyrite generations. As is also the case for galena and native silver, native gold is observed for the first time as inclusion in quartz which opens up, thus, new perspectives for prospecting and evaluating the potential for noble metals associated with the mineralization. Scanning Electron Microscope--Energy Dispersive Spectroscopy and Transmission electron microscopy analyses show, in addition, a large incorporation of trace elements, including Ag and Au, in mineral structures such as fahlores(tetrahedrite-tennantite) and chalcopyrite ones. The mineral/mineral associations, used as geothermometers, gave estimated temperatures for the mineralizing fluids varying from 254 to 330 ℃ for phase Ⅲ, from 254 to 350 ℃ for phase Ⅳ, and from 200 to 300 ℃ for phases Ⅴ and Ⅵ. The seventh and last identified mineralization phase, marked by a deposit of native gold, reflects a drop in the mineralizing fluid’s temperature(< 200 ℃) compatible with boiling conditions. Such results open up perspectives for the development of precious metal research and the revaluation of the Cu–Fe ore deposit at the Ain El Bey abandoned mine, as well as at the surrounding areas fitting in the geodynamic framework of the Africa-Europe plate boundary. 展开更多
关键词 Ore-formingfluids Mineral geochemistry Mineral geothermometers Native silver-gold Ain El Bey Ore deposit North Tunisia
下载PDF
Native and prosthetic septic arthritis in a university hospital in Saudi Arabia:A retrospective study
5
作者 Reham Kaki 《World Journal of Orthopedics》 2024年第8期722-733,共12页
BACKGROUND Septic arthritis,whether native or prosthetic,poses a significant challenge in clinical practice due to its potentially devastating consequences.Despite its clinical importance,there remains a dearth of com... BACKGROUND Septic arthritis,whether native or prosthetic,poses a significant challenge in clinical practice due to its potentially devastating consequences.Despite its clinical importance,there remains a dearth of comprehensive studies and standardized diagnostic criteria,particularly in the Kingdom of Saudi Arabia.AIM To investigate the epidemiology,microbiological profiles,and clinical characteristics of native and prosthetic septic joints in the Saudi Arabian population.METHODS Medical records of patients diagnosed with septic arthritis between January 1,2015,and December 31,2022,were retrospectively reviewed.Data regarding patient demographics,clinical presentation,microbiological cultures,treatment modalities,and outcomes were analyzed.RESULTS In a retrospective review of 52 cases of septic arthritis,a balanced gender distribution was observed(1:1 ratio),with the knee being the most commonly affected joint(80.8%).Methicillin-resistant Staphylococcus aureus predominated in native joints(24.2%),while Brucella spp.was more prevalent in prosthetic joints(21.1%).Joint preservation was achieved in most cases(84.6%),with no significant difference in clinical features between native and prosthetic joints.However,certain comorbidities were more common in native joint cases,including renal impairment(P=0.002),hemodialysis(P=0.004),heart disease(P=0.013),and chronic liver disease(P=0.048).At the same time,osteoarthritis was more prevalent in prosthetic joint cases(P=0.013).Vancomycin was the most frequently used antibiotic(26.9%),and most patients received antibiotics before joint aspiration(57.7%).Surgical intervention,predominantly arthrotomy,was required in most cases(32.7%).Notably,a significant association was found between joint type and mortality(odds ratio=0.587,P=0.048),as well as the Charlson comorbidity index and mortality(P=0.001).CONCLUSION This study highlighted distinctive microbiological profiles and etiological factors in septic arthritis cases in the Saudi Arabian population. 展开更多
关键词 Septic arthritis Native joint Prosthetic joint EPIDEMIOLOGY Diagnostic criteria Saudi Arabia
下载PDF
Successful treatment of acute liver failure due to Wilson’s disease: Serendipity or fortuity?
6
作者 Valeria Delle Cave Fabiola Di Dato +2 位作者 Pier Luigi Calvo Maria Immacolata Spagnuolo Raffaele Iorio 《World Journal of Hepatology》 2024年第8期1111-1119,共9页
BACKGROUND Acute liver failure(ALF)may be the first and most dramatic presentation of Wilson’s disease(WD).ALF due to WD(WD-ALF)is difficult to distinguish from other causes of liver disease and is a clear indication... BACKGROUND Acute liver failure(ALF)may be the first and most dramatic presentation of Wilson’s disease(WD).ALF due to WD(WD-ALF)is difficult to distinguish from other causes of liver disease and is a clear indication for liver transplantation.There is no firm recommendation on specific and supportive medical treatment for this condition.AIM To critically evaluate the diagnostic and therapeutic management of WD-ALF patients in order to improve their survival with native liver.METHODS A retrospective analysis of patients with WD-ALF was conducted in two pediatric liver units from 2018 to 2023.RESULTS During the study period,16 children(9 males)received a diagnosis of WD and 2 of them presented with ALF.The first was successfully treated with an unconventional combination of low doses of D-penicillamine and zinc plus steroids,and survived without liver transplant.The second,exclusively treated with supportive therapy,needed a hepatotransplant to overcome ALF.CONCLUSION Successful treatment of 1 WD-ALF patient with low-dose D-penicillamine and zinc plus steroids may provide new perspectives for management of this condition,which is currently only treated with liver transplantation. 展开更多
关键词 Fulminant liver failure Copper CHELATOR Zinc STEROIDS Liver transplantation Autoimmune hepatitis Prognostic score 24 hour-urinary copper excretion Native liver
下载PDF
Intelligence Driven Wireless Networks in B5G and 6G Era:A Survey
7
作者 GAO Yin CHEN Jiajun LI Dapeng 《ZTE Communications》 2024年第3期99-105,共7页
As the wireless communication network undergoes continuous expansion,the challenges associated with network management and optimization are becoming increasingly complex.To address these challenges,the emerging artifi... As the wireless communication network undergoes continuous expansion,the challenges associated with network management and optimization are becoming increasingly complex.To address these challenges,the emerging artificial intelligence(AI)and machine learning(ML)technologies have been introduced as a powerful solution.They empower wireless networks to operate autonomously,predictively,ondemand,and with smart functionality,offering a promising resolution to intricate optimization problems.This paper aims to delve into the prevalent applications of AI/ML technologies in the optimization of wireless networks.The paper not only provides insights into the current landscape but also outlines our vision for the future and considerations regarding the development of an intelligent 6G network. 展开更多
关键词 intelligent network native AI load prediction trajectory prediction
下载PDF
Extracorporeal organ support for critically ill patients:Overcoming the past,achieving the maximum at present,and redefining the future
8
作者 Panagiotis Papamichalis Katerina G Oikonomou +4 位作者 Maria Xanthoudaki Asimina Valsamaki Apostolia-Lemonia Skoura Sophia K Papathanasiou Achilleas Chovas 《World Journal of Critical Care Medicine》 2024年第2期19-28,共10页
Extracorporeal organ support(ECOS)has made remarkable progress over the last few years.Renal replacement therapy,introduced a few decades ago,was the first available application of ECOS.The subsequent evolution of ECO... Extracorporeal organ support(ECOS)has made remarkable progress over the last few years.Renal replacement therapy,introduced a few decades ago,was the first available application of ECOS.The subsequent evolution of ECOS enabled the enhanced support to many other organs,including the heart[veno-arterial extracorporeal membrane oxygenation(ECMO),slow continuous ultrafiltration],the lungs(veno-venous ECMO,extracorporeal carbon dioxide removal),and the liver(blood purification techniques for the detoxification of liver toxins).Moreover,additional indications of these methods,including the suppression of excessive inflammatory response occurring in severe disorders such as sepsis,coronavirus disease 2019,pancreatitis,and trauma(blood purification techniques for the removal of exotoxins,endotoxins,or cytokines),have arisen.Multiple organ support therapy is crucial since a vast majority of critically ill patients present not with a single but with multiple organ failure(MOF),whereas,traditional therapeutic approaches(mechanical ventilation for acute respiratory failure,antibiotics for sepsis,and inotropes for cardiac dysfunction)have reached the maximum efficacy and cannot be improved further.However,several issues remain to be clarified,such as the complexity and cost of ECOS systems,standardization of indications,therapeutic protocols and initiation time,choice of the patients who will benefit most from these interventions,while evidence from randomized controlled trials supporting their use is still limited.Nevertheless,these methods are currently a part of routine clinical practice in intensive care units.This editorial presents the past,present,and future considerations,as well as perspectives regarding these therapies.Our better understanding of these methods,the pathophysiology of MOF,the crosstalk between native organs resulting in MOF,and the crosstalk between native organs and artificial organ support systems when applied sequentially or simultaneously,will lead to the multiplication of their effects and the minimization of complications arising from their use. 展开更多
关键词 Kidney-liver replacement therapy Heart-lung support Blood purification Native–artificial organ crosstalk Multiple organ support therapy Extracorporeal organ support
下载PDF
The Role and Value of Sociolinguistics in English Language Teaching
9
作者 Fenhua Guo 《Journal of Contemporary Educational Research》 2024年第8期193-201,共9页
This paper aims to explore how the study of sociolinguistics can benefit teachers,particularly in the context of teaching English as a Foreign Language(EFL)in China.The article will first examine how sociolinguistic k... This paper aims to explore how the study of sociolinguistics can benefit teachers,particularly in the context of teaching English as a Foreign Language(EFL)in China.The article will first examine how sociolinguistic knowledge can reshape teachers’perceptions of“English,”focusing on aspects such as English varieties,World Englishes,and Chinese English.Following that,the article discusses the necessity of rethinking current practices in English language teaching,including the nativeness paradigm and the concept of communicative competence based on a reconceptualized view of“English.”Additionally,the discussion will focus on how teachers,informed by sociolinguistic awareness of non-native teachers’identities and teacher agency,can address and resolve existing challenges in EFL teaching.Finally,the article will conclude by summarizing the key issues discussed and highlighting the significance of studying sociolinguistics for language practitioners in China. 展开更多
关键词 World Englishes Chinese English English language teaching Nativeness Non-native English-speaking teachers
下载PDF
React Native的跨平台移动应用开发实践
10
作者 王硕 祁欣颖 《信息与电脑》 2024年第7期119-121,共3页
随着智能手机的普及,移动应用成了连接用户与服务的重要渠道。然而,面对iOS和Android等多个平台,开发者不得不重复开发同一应用以适配不同系统,这不仅消耗了大量的资源,也延长了产品的上市时间。React Native作为一种跨平台移动应用开... 随着智能手机的普及,移动应用成了连接用户与服务的重要渠道。然而,面对iOS和Android等多个平台,开发者不得不重复开发同一应用以适配不同系统,这不仅消耗了大量的资源,也延长了产品的上市时间。React Native作为一种跨平台移动应用开发框架,允许开发者使用Java Script编写应用,一次编码便可在多个平台上运行。本文通过实践案例分析了使用React Native进行跨平台移动应用开发的效率和成本效益,探讨了其在解决平台异质性问题上的有效性,并对比了React Native与其他跨平台框架的优势。结果表明,基于React Native的跨平台开发不仅能够显著提高开发效率,降低开发成本,而且还能提供与原生应用接近的用户体验,为移动应用开发提供了一种高效的解决方案。 展开更多
关键词 React Native 跨平台开发 移动应用 开发效率 成本效益
下载PDF
基于React Native的用户交互设计
11
作者 秦鹏 《电脑编程技巧与维护》 2024年第9期11-13,16,共4页
研究旨在探讨如何在基于React Native的跨平台应用开发中进行有效的人机交互设计。随着移动应用市场的持续扩大,跨平台开发框架(例如,React Native)提供了一种高效的方式来构建应用,但其成功与否往往取决于用户体验的质量。研究重点讨... 研究旨在探讨如何在基于React Native的跨平台应用开发中进行有效的人机交互设计。随着移动应用市场的持续扩大,跨平台开发框架(例如,React Native)提供了一种高效的方式来构建应用,但其成功与否往往取决于用户体验的质量。研究重点讨论了利用React Native的特性和工具来设计具有优秀人机交互的跨平台应用,通过实际案例和技术细节进行了深入探讨。 展开更多
关键词 React Native框架 跨平台应用开发 人机交互设计 实践方法
下载PDF
Effects of Calcium and Magnesium on Phosphorus Availability in Ferralsols and Rice Production in Forest Zones of Côte d’Ivoire
12
作者 Guy Fernand Yao Brahima Kone +5 位作者 Kouadio Amani Franck Michaël Lemonou Bahan Jean Lopez Essehi Brou Kouame François Lompo Albert Yao-Kouame 《Journal of Agricultural Chemistry and Environment》 2024年第1期33-53,共21页
Phosphorus bioavailability has long been a recurring problem in tropical acid soils. A pot experiment was carried out during three (3) successive rice production cycles at Adiopodoumé to evaluate the response of ... Phosphorus bioavailability has long been a recurring problem in tropical acid soils. A pot experiment was carried out during three (3) successive rice production cycles at Adiopodoumé to evaluate the response of the NERICA 5 rice accession to various doses of calcium, magnesium and phosphorous. The experiment was conducted using a randomized split-plot design. The interactive effects of calcium carbonate (0, 25, 50 and 75 kg·Ca·ha<sup>-1</sup>) and magnesium sulfate (0, 25, 50 and 75 kg·Mg·ha<sup>-1</sup>) and Togo natural phosphate (0, 25, 50 and 75 kg·P·ha<sup>-1</sup>) were determined at each production cycle. The results showed that single-dose natural phosphate supplementation for three cropping cycles resulted in an average enrichment of around 2 mg·P·kg<sup>-1</sup> after each trial following its continuous dissolution, with an increase in DSP (33.31% to 70.52%). The study revealed one strategy for managing and enhancing native P with cations and another for exogenous P: there would be a synergy of Ca/Mg on native P, whereas an antagonism would characterize the two parameters in phosphate fertilization. 展开更多
关键词 Soil Acidity Native and Exogenous Phosphorus Free Iron Ca/Mg Balances Rice Growing Côte d’Ivoire
下载PDF
纯XML数据库研究综述 被引量:34
13
作者 冯建华 钱乾 +3 位作者 廖雨果 李国良 塔娜 周立柱 《计算机应用研究》 CSCD 北大核心 2006年第6期1-7,共7页
虽然XML是一种专门为Internet所设计的标记语言,但是它已经成为Internet上数据表示和数据交换的标准。如何对XML文档进行有效管理与快速查询是当前学术界的研究热点,即所谓的XML数据库。主要对当前XML数据库的研究现状与发展趋势进行全... 虽然XML是一种专门为Internet所设计的标记语言,但是它已经成为Internet上数据表示和数据交换的标准。如何对XML文档进行有效管理与快速查询是当前学术界的研究热点,即所谓的XML数据库。主要对当前XML数据库的研究现状与发展趋势进行全面的论述与分析,并对其中尚未解决的挑战性问题进行了客观的评价与分析。 展开更多
关键词 扩展标记语言 XML数据库 NATIVE XML数据库 存储策略 查询优化 X-代数
下载PDF
Genetic Diversity in Wild Grapes Native to China Based on Randomly Amplified Polymorphic DNA (RAPD) Analysis 被引量:29
14
作者 罗素兰 贺普超 +1 位作者 郑学勤 周鹏 《Acta Botanica Sinica》 CSCD 2001年第2期158-163,共6页
The use of the RAPD technique was investigated on a set of 73 genotypes of 18 wild grape species native to China, and one interspecific hybrid, seven Vitis vinifera L. cultivars, one rootstock cultivar and one str... The use of the RAPD technique was investigated on a set of 73 genotypes of 18 wild grape species native to China, and one interspecific hybrid, seven Vitis vinifera L. cultivars, one rootstock cultivar and one strain of V. riparia L. Genetic diversity among these grapes was investigated based on RAPD analysis. The screening of 280 decamer oligonucleotides allowed the selection of 20 primers used for the analysis. A total of 191 RAPD markers were produced from the 20 selected primers. Relationships among the 83 clones or accessions based on their genetic distances were clustered using unweighted pair_group method arithmetic average (UPGMA) analysis in a dendrogram. Twenty_two clusters which fortunately adapted to 22 grape species level were clearly resolved on the dendrogram. The 18 wild grape species native to China were grouped into ten subclusters. The largest distance was found between V. riparia L., V. vinifera L., interspecific hybrid ( V. vinifera L.× V. larbrusca L.) and the wild grapes native to China. Among the wild grapes native to China, the largest distance was found between V. hancockii Hance and the other wild species. V. qinlingensis P.C.He was the second. Large genetic variation occurred among the different flower_type clones in one species. 展开更多
关键词 the wild grapes native to China VITIS genetic distance RAPD
下载PDF
Native XML数据库技术综述 被引量:13
15
作者 逯鹏 吕良双 高庆一 《计算机科学》 CSCD 北大核心 2004年第4期84-88,共5页
XML成为数据统一描述和表示的标准。如何管理已经出现的大量的XML数据成为重要的问题。NativeXML数据库(NXD)是解决XML数据管理的重要手段。分析和综述了NXD研究现状,以及几个主要研究方向:数据模型、查询语言、存储技术等。分析了NXD... XML成为数据统一描述和表示的标准。如何管理已经出现的大量的XML数据成为重要的问题。NativeXML数据库(NXD)是解决XML数据管理的重要手段。分析和综述了NXD研究现状,以及几个主要研究方向:数据模型、查询语言、存储技术等。分析了NXD的基本特性和具有代表性的NXD系统,最后指出了目前研究存在的不足以及该学科的发展趋势。 展开更多
关键词 NATIVE XML 数据库 数据管理 数据模型 数据处理 数据库管理系统
下载PDF
syngo NATIVE无对比剂MR血管成像技术 被引量:13
16
作者 王超洪 孙志国 +1 位作者 张琼 安靖 《磁共振成像》 CAS 2010年第3期214-217,共4页
syngo NATIVE是西门子磁共振事业部独家推出的无对比剂MR血管成像软件包,经过严格的内部和外部测试,以及全球数十名临床专家的反复应用,获得大量的建议和好评,目前已经成为一种成熟和完善的技术。syngo NATIVE包括两种不同的技术:syngo ... syngo NATIVE是西门子磁共振事业部独家推出的无对比剂MR血管成像软件包,经过严格的内部和外部测试,以及全球数十名临床专家的反复应用,获得大量的建议和好评,目前已经成为一种成熟和完善的技术。syngo NATIVE包括两种不同的技术:syngo NATIVE True FISP和syngo NATIVE SPACE,分别用于腹部动脉(特别是肾动脉)和外周动脉的成像。本文分别对这两种技术的原理以及临床检查的要点进行了介绍。 展开更多
关键词 磁共振成像 血管造影术 syngo NATIVE
下载PDF
JNI技术实现跨平台开发的研究 被引量:40
17
作者 任俊伟 林东岱 《计算机应用研究》 CSCD 北大核心 2005年第7期180-184,共5页
在实践开发网格计算服务的过程中遇到了跨平台与服务运行效率的问题,在解决问题的过程中对Java的JNI技术进行了较深入的研究。对开发过程中使用JNI技术的重点和难点所作研究后的一个归纳和总结,并结合具体的开发实例由浅入深地介绍了有... 在实践开发网格计算服务的过程中遇到了跨平台与服务运行效率的问题,在解决问题的过程中对Java的JNI技术进行了较深入的研究。对开发过程中使用JNI技术的重点和难点所作研究后的一个归纳和总结,并结合具体的开发实例由浅入深地介绍了有效使用JNI技术实现跨平台开发同时兼顾效率的有效方法。 展开更多
关键词 JNI(Java NATIVE Interface) 本地方法调用 跨平台 共享库 信息传递
下载PDF
XML数据库的研究与应用 被引量:16
18
作者 周爱武 李孙长 +1 位作者 程博 夏松 《计算机技术与发展》 2009年第9期218-221,224,共5页
XML是一种专门为Internet所设计的标记语言,随着XML的大量应用,它已经成为Internet上数据表示和数据交换的标准,如何有效地管理大量的XML数据显得非常重要。使用数据库技术对XML进行管理,这已经成为一种必然的发展趋势。XML与数据库相... XML是一种专门为Internet所设计的标记语言,随着XML的大量应用,它已经成为Internet上数据表示和数据交换的标准,如何有效地管理大量的XML数据显得非常重要。使用数据库技术对XML进行管理,这已经成为一种必然的发展趋势。XML与数据库相结合已经成为一个新的研究领域,也是XML和数据库发展的趋势。文中探讨和分析了XML数据库的相关知识,介绍了Native XML数据库及一个NXD系统eXist,最后表明XML数据库将成为一个新的研究领域。 展开更多
关键词 XML 数据库 NATIVE XML数据库 eXist
下载PDF
贝叶斯树算法在异常入侵检测中的应用 被引量:4
19
作者 李永忠 赵博 +1 位作者 杨鸽 徐静 《江苏科技大学学报(自然科学版)》 CAS 北大核心 2008年第1期52-56,共5页
研究了Windows平台下异常检测方法,提出了一种利用Windows Native API调用序列和基于贝叶斯树算法的主机服务进程规则与对应概率分布生成算法。根据长为N-1的Windows Native API调用序列预测第N个调用的概率分布,对生成的概率序列用U检... 研究了Windows平台下异常检测方法,提出了一种利用Windows Native API调用序列和基于贝叶斯树算法的主机服务进程规则与对应概率分布生成算法。根据长为N-1的Windows Native API调用序列预测第N个调用的概率分布,对生成的概率序列用U检验方法作为异常检测算法。以贝叶斯树作为弱分类算法,利用AdaBoost-M1方法构造多个基于贝叶斯树的概率分布序列,并按一定方式把它们组合成一个加强的概率分布序列进行入侵检测。实验结果表明这种方法能明显提高模型预测能力。 展开更多
关键词 入侵检测 Windows NATIVE API 贝叶斯树 AdaBoost—M1
下载PDF
移动APP开发模式研究 被引量:14
20
作者 李莉 张超然 +1 位作者 刘丹 李纪成 《长春理工大学学报(自然科学版)》 2016年第5期110-114,126,共6页
对智能手机的Native APP,Web APP和Hybrid APP三种开发模式进行了深入研究。分析了各种模式的优缺点。描述了属于Hybrid APP开发模式的Phone Gap开发框架及三种开发模式的环境配置,在Android模拟器上进行了三种模式实验验证,达到了预期... 对智能手机的Native APP,Web APP和Hybrid APP三种开发模式进行了深入研究。分析了各种模式的优缺点。描述了属于Hybrid APP开发模式的Phone Gap开发框架及三种开发模式的环境配置,在Android模拟器上进行了三种模式实验验证,达到了预期的结果。分析了HTML5对开发模式的影响。最后,根据每种手机APP开发模式的特性,对其适用的开发情境进行了总结。 展开更多
关键词 NATIVE APP WEB APP HYBRID APP
下载PDF
上一页 1 2 27 下一页 到第
使用帮助 返回顶部