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企业竞争力研究的层次结构与研究原则 被引量:2
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作者 张玉利 金明律 《科学管理研究》 CSSCI 北大核心 1996年第1期20-24,共5页
企业竞争力研究的层次结构与研究原则张玉利,金明律南开大学国际企业管理系企业是商品生产和交换的具体承担者,是经济活动(包括国内和国际经济活动)的主体。增强企业的竞争能力,不论对提高企业的经济效益还是增强所在行业。地区、... 企业竞争力研究的层次结构与研究原则张玉利,金明律南开大学国际企业管理系企业是商品生产和交换的具体承担者,是经济活动(包括国内和国际经济活动)的主体。增强企业的竞争能力,不论对提高企业的经济效益还是增强所在行业。地区、乃至国家的竞争力都是十分重要的。企... 展开更多
关键词 企业竞争力 竞争力研究 层次结构 国际竞争力 市场占有率 评价指标 影响因素 竞争能力 发展·趋势 研究工作
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Research Progress on Plant Source Herbicide Adjuvants 被引量:7
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作者 孟桂元 周静 金晨钟 《Agricultural Science & Technology》 CAS 2016年第11期2619-2621,2626,共4页
As the important components of pesticide adjuvants, vegetable oil and its derivative adjuvants will be the focus of future development of herbicide adjuvants due to their superiority in good affinity with plants, stro... As the important components of pesticide adjuvants, vegetable oil and its derivative adjuvants will be the focus of future development of herbicide adjuvants due to their superiority in good affinity with plants, strong biological degradability, few risk of damage, environrnental safety and ability to improve the weed control efficient. The research progress and application status of the plant source herbicide adjuvants were summarized, as well as the weeding enhancement mechanism and the effects on the environment and non-target organisms, and the existing problems and development trends were reviewed. 展开更多
关键词 HERBICIDE Plant source Enhancement mechanism DeveLopment trend
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An Overview of Research on Microbial Herbicide 被引量:5
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作者 刘艺妩 刘开林 柏连阳 《Agricultural Science & Technology》 CAS 2013年第10期1468-1470,1485,共4页
The development of microbial herbicide for weed control has been serious- ly regarded all over the world and has made rapid progress in recent years. This paper presents a comprehensive review on domestic and abroad r... The development of microbial herbicide for weed control has been serious- ly regarded all over the world and has made rapid progress in recent years. This paper presents a comprehensive review on domestic and abroad research progress of microbial herbicide and mainly introduces the microbial herbicide products and mi- crobial sources with commercialization potential, and then proposes an outlook for their development tendency and application prospect. 展开更多
关键词 Microbial herbicide WEED Research and development OVERVIEW
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Analysis on Status quo and Future Development of Fruit and Vegetable Protreatment 被引量:1
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作者 杨旭海 张茜 +1 位作者 李红娟 张新建 《Agricultural Science & Technology》 CAS 2015年第12期2809-2811,2815,共4页
Pretreatment on vegetable and fruit is a key chain of drying process. The research analyzed mechanisms and applications of different pretreatments such as blanching, freezing, liquid glucose pretreatment, NaCI dipping... Pretreatment on vegetable and fruit is a key chain of drying process. The research analyzed mechanisms and applications of different pretreatments such as blanching, freezing, liquid glucose pretreatment, NaCI dipping, and high-voltage elec- tric field, and proposed the development prospect. 展开更多
关键词 Fruit and vegetable PRETREATMENT DRYING MECHANISM Application De- velopment trend
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国内低氧训练研究现状的可视化分析 被引量:1
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作者 李志刚 林文弢 《体育科研》 2018年第1期56-65,共10页
为了深入分析国内低氧训练研究的现状,运用CiteSpaceⅢ和CNKI的可视化功能对近20年来发表在国内体育核心期刊上有关低氧训练的文献进行计量学统计和可视化分析。结果表明,总体研究趋势以2008年为顶点呈正态分布,国内形成了凸显的科研力... 为了深入分析国内低氧训练研究的现状,运用CiteSpaceⅢ和CNKI的可视化功能对近20年来发表在国内体育核心期刊上有关低氧训练的文献进行计量学统计和可视化分析。结果表明,总体研究趋势以2008年为顶点呈正态分布,国内形成了凸显的科研力量。研究的热点主题包括低氧训练方式的多样化,低氧训练的监控,提高运动员的有氧和无氧能力,对机体的免疫力、认知功能的影响,在控重减肥中的应用,低氧训练干预下的氧化应激和细胞凋亡情况,低氧训练习服与基因多态性的关系,低氧训练对机体作用的分子机理的探讨等方面。新的低氧训练方式的应用、低氧训练的健康促进功能、低氧训练的分子机理的探讨和学科交叉成为今后的研究趋势。 展开更多
关键词 低氧训练 知识图谱 可视化 训练方式 研究热点 发展趋势
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Analysis of Drought Changes and Drought Mitigation in Xiji County of Ningxia
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作者 孙俊 张学艺 +2 位作者 李剑萍 齐旭峰 魏广泱 《Agricultural Science & Technology》 CAS 2011年第11期1682-1686,共5页
[Objective] The aim was to study the characteristics of the changes of extreme weather climate incidents such as severe drought in northwest and rainstorm in Xiji County of Ningxia. [Method] Precipitation anomaly perc... [Objective] The aim was to study the characteristics of the changes of extreme weather climate incidents such as severe drought in northwest and rainstorm in Xiji County of Ningxia. [Method] Precipitation anomaly percentage was applied to divide drought level and for statistics analysis. Seasonal index, linear tendency, and 5-years gliding average were used to reflect the trend of drought changes. The circulation wave of temporal sequence used polynomial expression to simulate the interannual variation scale. The positive part of the polynomial expression used bar chart to simulate interannual variation scale. [Result] The index of drought season from November to June was large. The general trend of annual drought was increasing. The drought of interannual scale was most serious around 1977, about 15 and 20 years. The drought in recent years went up. The general situation of drought, interannual scale and changes of interannual scales from March to May and from September to October were discussed. Based on the weather at 500 hPa, the first rain in Xiji and the drought-turning-into-rain situation were classified. [Conclusion]These may provide reference value to the prevention and mitigation of drought. 展开更多
关键词 Drought in Xiji of Ningxia Development tendency Different scales Drought mitigation situation
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Situation and Development Tendency of Indoor Positioning 被引量:82
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作者 邓中亮 余彦培 +2 位作者 袁协 万能 杨磊 《China Communications》 SCIE CSCD 2013年第3期42-55,共14页
This paper introduces the significance of indoor positioning and analyzes the related problems. The latest research on indoor positioning is introduced. Further, the positioning accuracy and the cost of typical local ... This paper introduces the significance of indoor positioning and analyzes the related problems. The latest research on indoor positioning is introduced. Further, the positioning accuracy and the cost of typical local and wide area indoor positioning systems are compared. The results of the comparison show that Time & Code Division-Orthogonal Frequency Division Multiplexing (TC-OFDM) is a system that can achieve real-time meter-accuracy of indoor positioning in a wide area. Finally, in this paper, we indicate that the seamless high-accuracy indoor positioning in a wide area is the development trend of indoor positioning. The seamless Location Based Services (LBS) architecture based on a heterogeneous network, key technologies in indoor positioning for decimeter-accuracy and seamless outdoor and indoor Geographic Information System (GIS) are elaborated as the most important research fields of future indoor positioning. 展开更多
关键词 indoor positioning LBS REVIEW wide area local area TC-OFDM
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Development Trends in Additive Manufacturing and 3D Printing 被引量:57
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作者 Bingheng Lu Dichen Li Xiaoyong Tian 《Engineering》 SCIE EI 2015年第1期85-89,共5页
Additive manufacturing and 3D printing tech-nology have been developing rapidly in the last 30 years, and indicate great potential for future development. The promising future of this technology makes its impact on tr... Additive manufacturing and 3D printing tech-nology have been developing rapidly in the last 30 years, and indicate great potential for future development. The promising future of this technology makes its impact on traditional industry unpredictable. 3D printing will propel the revolution of fabrication modes forward, and bring in a new era for customized fabrication by realizing the five "any"s: use of almost any material to fabricate any part, in any quantity and any location, for any industrial field. Innovations in material, design, and fabrication processes will be inspired by the merging of 3D-printing technology and processes with traditional manufacturing processes. Finally, 3D printing will become as valuable for manufacturing industries as equivalent and subtractive manufacturing processes. 展开更多
关键词 additive manufacturing 3D printing fabricationmodes customized fabrication innovative design
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Research and development trends of hydrometallurgy:An overview based on Hydrometallurgy literature from 1975 to 2019 被引量:13
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作者 Li-pan JIA Jiang-jiang HUANG +5 位作者 Ze-long MA Xu-heng LIU Xing-yu CHEN Jiang-tao LI Li-hua HE Zhong-wei ZHAO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第11期3147-3160,共14页
Modern hydrometallurgy has been developing for more than 100 years and the related articles keep piling up.Based on a bibliometric analysis of the articles in Hydrometallurgy,the most authoritative journal in the fiel... Modern hydrometallurgy has been developing for more than 100 years and the related articles keep piling up.Based on a bibliometric analysis of the articles in Hydrometallurgy,the most authoritative journal in the field of hydrometallurgy,we try to catch the research and development trends from a global perspective.Firstly,keywords burstness shows that rare earth,recycling,lithium,ionic liquid,and thorium are the hotspots in recent years,and the economic and technological reasons behind them were discussed in depth.Secondly,the proportion of biohydrometallurgy grows fast from 5%to 13%and the related articles are almost all about bioleaching.There are some new directions such as direct preparation of materials in hydrometallurgical processes and ion-imprinted techniques.Thirdly,the advanced instrument analysis methods such as XAFS(X-ray absorption fine structure),gene sequencing,and micro-CT promote the deep understanding of hydrometallurgy mechanism.Finally,the cooperation network and contribution of the main institutes were mapped. 展开更多
关键词 development trends LEACHING solvent extraction BIOHYDROMETALLURGY electro-hydrometallurgy CiteSpace
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Development path of Chinese low-carbon cities based on index evaluation 被引量:10
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作者 YANG Xiu WANG Xue-Chun ZHOU Ze-Yu 《Advances in Climate Change Research》 SCIE CSCD 2018年第2期144-153,共10页
This work takes the 36 cities from China's low-carbon pilot project as the research object and uses the carbon emission per capita and GDP per capita to categorize the 36 cities into four types to reveal their low-ca... This work takes the 36 cities from China's low-carbon pilot project as the research object and uses the carbon emission per capita and GDP per capita to categorize the 36 cities into four types to reveal their low-carbon development status; these four types are leading cities, developing cities, latecomer cities, and exploring cities. On the basis of an index system that quantitatively describes low-carbon development, this research analyzes the characteristics, development trends, and low-carbon development pathways of the four types of cities. According to the present situation and objectives of national emissions and considering the differences in development stages, challenges, and opportunities for each type of the city, this research presents recommendations for the low-carbon roadmap and the medium- and long-term (by 2030) emission trend routes of different types of regions in China. 展开更多
关键词 CITY Low-carbon development Index evaluation Development path
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Trends of Urban Air Pollution in Zhengzhou City in 1996-2008 被引量:6
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作者 DU Xile LU Changhe +1 位作者 WANG Hairong MA Jianhua 《Chinese Geographical Science》 SCIE CSCD 2012年第4期402-413,共12页
Urban air pollution is a commonly concerned environmental problem in the world. Identification of air quality trend using long-term monitoring data is helpful to understand the effectiveness of pollution control strat... Urban air pollution is a commonly concerned environmental problem in the world. Identification of air quality trend using long-term monitoring data is helpful to understand the effectiveness of pollution control strategies. This study, using data from six monitoring stations in Zhengzhou City, analyzed the changing trend in concentrations of SO2, NOJNO2 and TSP/PM10 in 1996-2008, based on non-parametric Mann-Kendall test and Sen's slope estimator, and evaluated the comprehensive air pollution level using Multi-Pollutant Index (MPI). It was found that the concen- tration of each pollutant exceeded obviously the World Health Organization (WHO) guideline value, but the changing trend varied: SO2 and NO2 were significantly increased mainly due to an increase in coal consumption and vehicle number, while NOx, TSP and PM10 decreased. The air pollution was serious, and differed markedly among the three functional regions: it is the most severe in the Industrial and Residential Area (IRA), followed by the Transportation Hub and Business District (THBD), and then the High-tech, Cultural and Educational Area (HCEA). Different from NO2 concentration that had a similar change trend/rate among the function regions, the change rate of PM10 concentra- tion differed spatially, decreased much more obviously in THBD than other two regions. For the whole city, the com- prehensive air pollution level declined gradually, illustrating that the air quality in Zhengzhou was improved in the last decade. 展开更多
关键词 urban air pollution Mann-Kendall test Sen's method Multi-Pollutant Index (MPI) Zhengzhou
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Century-long variability and trends in daily precipitation characteristics at three Finnish stations 被引量:5
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作者 Masoud IRANNEZHAD Hannu MARTTILA +1 位作者 Deliang CHEN Bj?rn KL?VE 《Advances in Climate Change Research》 SCIE CSCD 2016年第1期54-69,共16页
Long-term variations and trends in a wide range of statistics for daily precipitation characteristics in terms of intensity, frequency and duration in Finland were analysed using precipitation records during 1908e2008... Long-term variations and trends in a wide range of statistics for daily precipitation characteristics in terms of intensity, frequency and duration in Finland were analysed using precipitation records during 1908e2008 from 3 meteorological stations in the south(Kaisaniemi),centre(Kajaani) and north(Sodankyl€a). Although precipitation days in northern part were more frequent than in central and southern parts, daily precipitation intensity in the south was generally higher than those in the centre and north of the country. Annual sum of very light precipitation(0 mm < daily precipitation long-term 50 th percentile of daily precipitation more than 0 mm) significantly( p < 0.05) decreased over time,with the highest rate in northern Finland. These decreasing trends might be the result of significant increases in frequency of days with very light precipitation at all the stations, with the highest and lowest rates in northern and southern Finland, respectively. Ratio of annual total precipitation to number of precipitation days also declined in Finland over 1908e2008, with a decreasing north to south gradient. However, annual duration indices of daily precipitation revealed no statistically significant trends at any station. Daily precipitation characteristics showed significant relationships with various well-known atmospheric circulation patterns(ACPs). In particular, the East Atlantic/West Russia(EA/WR)pattern in summer was the most influential ACP negatively associated with different daily precipitation intensity, frequency and duration indices at all three stations studied. 展开更多
关键词 Daily precipitation characteristics Trend analysis Intensity Frequency Duration EXTREMES Atmospheric circulation patterns FINLAND
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China’s Service Sector towards 2035:Outlook,Strategic Position and Policy Advice 被引量:17
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作者 Xia Jiechang Xu Ziyan 《China Economist》 2021年第1期58-75,共18页
China is setting out on a new journey of building a modern socialist country in all respects after achieving moderate prosperity.Modern services are an important part of China’s economy,underpinning China’s developm... China is setting out on a new journey of building a modern socialist country in all respects after achieving moderate prosperity.Modern services are an important part of China’s economy,underpinning China’s development towards a great modern socialist country.Globalization,industrial development,urbanization,innovation and income growth will drive China’s service sector development.By 2035,the service sector will account for 60.98%and 59.12%of total value-added and employment,respectively,and labor productivity in the service sector will rise from 145,500 yuan/person in 2019 to 282,300 yuan/person.The Fifth Plenum of the 19th CPC Central Committee called for“basically achieving the vision of socialist modernization by 2035.”According to the CPC Central Committee’s overall arrangements for the 2035 vision,we must identify a clear strategic position and tasks for the development of modern services as a key element of the modern industrial system,enhance service sector competitiveness,and achieve service sector modernization.To achieve this strategic goal,we must promote digitalized,intelligent,platform-based,standardized,and quality-oriented service sector development.We must give play to the decisive role of the market and the macro-regulatory role of the government in spurring service innovation,industry integration and clustering,and service sector reform and openness. 展开更多
关键词 service sector trends service sector modernization competitive service-based economy implementation strategy
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Incidence and mortality of female breast cancer in the AsiaPacific region 被引量:35
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作者 Danny R.Youlden Susanna M.Cramb +1 位作者 Cheng Har Yip Peter D.Baade 《Cancer Biology & Medicine》 SCIE CAS CSCD 2014年第2期101-115,共15页
Objective: To provide an overview of the incidence and mortality of female breast cancer for countries in the Asia-Pacific region.Methods: Statistical information about breast cancer was obtained from publicly availab... Objective: To provide an overview of the incidence and mortality of female breast cancer for countries in the Asia-Pacific region.Methods: Statistical information about breast cancer was obtained from publicly available cancer registry and mortality databases(such as GLOBOCAN), and supplemented with data requested from individual cancer registries. Rates were directly age-standardised to the Segi World Standard population and trends were analysed using joinpoint models.Results: Breast cancer was the most common type of cancer among females in the region, accounting for 18% of all cases in 2012, and was the fourth most common cause of cancer-related deaths(9%). Although incidence rates remain much higher in New Zealand and Australia, rapid rises in recent years were observed in several Asian countries. Large increases in breast cancer mortality rates also occurred in many areas, particularly Malaysia and Thailand, in contrast to stabilising trends in Hong Kong and Singapore, while decreases have been recorded in Australia and New Zealand. Mortality trends tended to be more favourable for women aged under 50 compared to those who were 50 years or older. Conclusion: It is anticipated that incidence rates of breast cancer in developing countries throughout the Asia-Pacific region will continue to increase. Early detection and access to optimal treatment are the keys to reducing breast cancerrelated mortality, but cultural and economic obstacles persist. Consequently, the challenge is to customise breast cancer control initiatives to the particular needs of each country to ensure the best possible outcomes. 展开更多
关键词 Asia-Pacific region female breast cancer epidemiology incidence mortality
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STUDY OF SETTING UP THE FOREST RESOURCES MANAGEMENT INFORMATION SYSTEM BASED ON WEBGIS 被引量:7
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作者 WU Su-li, LOU Quan-sheng, QUAN Zhi-jie, LI Xiao-jun (Northwest Sci-tech University of Agriculture and Forestry, Xi’an 712100, P. R. China) 《Chinese Geographical Science》 SCIE CSCD 2003年第1期56-61,共6页
Based on an analysis of the characteristics of the Forest Resources Management Information System of each development phase, and consideration of the technical trend in Geographic Information System (GIS) in the Inter... Based on an analysis of the characteristics of the Forest Resources Management Information System of each development phase, and consideration of the technical trend in Geographic Information System (GIS) in the Internet Age, this paper explores the importance and the feasibility of setting up Forest Resources Management Information System based on the WEBGIS. At the same time, based on the experience of our study, the paper explores the function, structure and method of developing the Forest Resources Management Information System based on WEBGIS. With the technology of WEBGIS, the Forest Resources Management Information System with data from Huoditang Farm was set up, which makes a great impact on forest resources management. So setting up the Forest Resources Management Information System based on WEBGIS is a trend of forest resources management. In the course of setting up this system, we must pay attention to following questions: 1) unify data standard and information encoding; 2) change mind. 展开更多
关键词 WEBGIS forest resources management information system
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Trends in the eradication rates of Helicobacter pylori infection for eleven years 被引量:3
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作者 Jai Hoon Yoon Gwang Ho Baik +10 位作者 Kyoung Min Sohn Dae Yong Kim Yeon Soo Kim Ki Tae Suk Jin Bong Kim Dong Joon Kim Jin Bae Kim Woon Geon Shin Hak Yang Kim Il Hyun Baik Hyun Joo Jang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第45期6628-6634,共7页
AIM:To evaluate the trends in the eradication rate of Helicobacter pylori(H.pylori) over the past 11 years in a single center.METHODS:This retrospective study covered the period from January 2000 to December 2010.We e... AIM:To evaluate the trends in the eradication rate of Helicobacter pylori(H.pylori) over the past 11 years in a single center.METHODS:This retrospective study covered the period from January 2000 to December 2010.We evaluated 5746 patients diagnosed with gastric ulcers(GU),duodenal ulcers(DU),GU + DU,or nonpeptic ulcers associated with an H.pylori infection.We treated them annually with the 2 wk standard first-line triple regimen,proton pump inhibitor(PPI) + amoxicilin + clarithromycin(PAC;PPI,clarithromycin 500 mg,and amoxicillin 1 g,all twice a day).The follow-up test was performed at least 4 wk after the completion of the 2 wk standard H.pylori eradication using the PAC regimen.We also assessed the eradication rates of 1 wk second-line therapy with a quadruple standard regimen(PPI b.i.d.,tripotassium dicitrate bismuthate 300 mg q.i.d.,metronidazole 500 mg t.i.d.,and tetracycline 500 mg q.i.d.) after the failure of the first-line therapy.Statistical analysis was performed with 95%CI for the differences in the annual eradication rates.RESULTS:A total of 5746 patients [2333 males(58.8%),1636 females(41.2%);mean age of males vs females 51.31 ± 13.1 years vs 52.76 ± 13.6 years,P < 0.05,total mean age 51.9 ± 13.3 years(mean ± SD)] were investigated.Among these patients,1674 patients were excluded:35 patients refused treatment;18 patients ceased H.pylori eradication due to side effects;1211 patients had inappropriate indications for H.pylori eradication,having undergone stomach cancer operation or chemotherapy;and 410 patients did not undergo the follow-up.We also excluded 103 patients who wanted to stop eradication treatment after only 1 wk due to poor compliance or the side effects mentioned above.Finally,we evaluated the annual eradication success rates in a total of 3969 patients who received 2 wk first-line PAC therapy.The endoscopic and clinical findings in patients who received the 2 wk PAC were as follows:gastric ulcer in 855(21.5%);duodenal ulcer in 878(22.1%);gastric and duodenal ulcer in 124(3.1%),erosive,atrophic gastritis and functional dyspepsia in 2055(51.8%);and other findings(e.g.,MALToma,patients who wanted to receive the therapy even though they had no abnormal endoscopic finding) in 57(0.5%).The overall eradication rate of the 2 wk standard firstline triple regimen was 86.5%.The annual eradication rates from 2000 to 2010 were 86.7%,85.4%,86.5%,83.3%,89.9%,90.5%,88.4%,84.5%,89.1%,85.8%,and 88.3%,sequentially(P = 0.06).No definite evidence of a significant change in the eradication rate was seen during the past eleven years.The eradication rates of second-line therapy were 88.9%,82.4%,85%,83.9%,77.3%,85.7%,84.4%,87.3%,83.3%,88.9%,and 84%(P = 0.77).The overall eradication rate of 1 wk quadruple second-line therapy was 84.7%.There was no significant difference in the eradication rate according to the H.pylori associated diseases.CONCLUSION:This study showed that there was no trend change in the H.pylori eradication rate over the most recent 11 years in our institution. 展开更多
关键词 Helicobacter pylori ERADICATION Protonpump inhibitor Therapy CLARITHROMYCIN
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A User Participation Behavior Prediction Model of Social Hotspots Based on Influence and Markov Random Field 被引量:2
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作者 Yunpeng Xiao Jiawei Lai Yanbing Liu 《China Communications》 SCIE CSCD 2017年第5期145-159,共15页
Hotspot topic trends can be captured by analyzing user attributes and historical behavior in social network. In this paper, we propose a user participation behavior prediction model for social hotspots, based on user ... Hotspot topic trends can be captured by analyzing user attributes and historical behavior in social network. In this paper, we propose a user participation behavior prediction model for social hotspots, based on user behavior and relationship data, to predict user participation behavior and topic development trends. Firstly, for the complex factors of user behavior, three dynamic influence factor functions are defined, including individual, peer and community influence. These functions take timeliness into account using a time discretization method. Secondly, to determine laws of individual behavior and group behavior within a social topic, a hotspot user participation behavior prediction model is proposed and associated with the basic concepts of randora field and Markov property in information diffusion. The experimental results show that the model can not only dynamically predict the individual behavior, but also grasp the development trends of topics. 展开更多
关键词 social network hotspot topic behavior prediction Markov random field influence factor
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Analysis of stochastic characteristics of the Benue River flow process 被引量:1
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作者 Martins Y. OTACHE Mohammad BAKIR 李致家 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2008年第2期142-151,共10页
Stochastic characteristics of the Benue River streamflow process are examined under conditions of data austerity. The streamflow process is investigated for trend, non-stationarity and seasonality for a time period of... Stochastic characteristics of the Benue River streamflow process are examined under conditions of data austerity. The streamflow process is investigated for trend, non-stationarity and seasonality for a time period of 26 years. Results of trend analyses with Mann-Kendall test show that there is no trend in the annual mean discharges. Monthly flow series examined with seasonal Kendall test indicate the presence of positive change in the trend for some months, especially the months of August, January, and February. For the stationarity test, daily and monthly flow series appear to be stationary whereas at 1%, 5%, and 10% significant levels, the stationarity alternative hypothesis is rejected for the annual flow series. Though monthly flow appears to be stationary going by this test, because of high seasonality, it could be said to exhibit periodic stationarity based on the seasonality analysis. The following conclusions are drawn: (1) There is seasonality in both the mean and variance with unimodal distribution. (2) Days with high mean also have high variance. (3) Skewness coefficients for the months within the dry season period are greater than those of the wet season period, and seasonal autocorrelations for streamflow during dry season are generally larger than those of the wet season. Precisely, they are significantly different for most of the months. (4) The autocorrelation functions estimated "over time" are greater in the absolute value for data that have not been deseasonalised but were initially normalised by logarithmic transformation only, while autocorrelation functions for i = 1, 2 365 estimated "over realisations" have their coefficients significantly different from other coefficients. 展开更多
关键词 TREND stationarity SEASONALITY over time over realisation STOCHASTIC SKEWNESS
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STUDY ON DEVELOPMENT STRATEGY OF SHIPPING CENTERS AND TRANSPORTATION NETWORKS IN THE YELLOW SEA RIM 被引量:2
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作者 JIN Feng-jun (Institute of Geographic Sciences and Natural Resources Research, Chinese Acad emy of Sciences, Beijing 100101, P.R. China) 《Chinese Geographical Science》 SCIE CSCD 2003年第2期97-103,共7页
It is very important to establish cooperative mechanism to guarantee allmembers to develop their e-conomies in the Yellow Sea Rim. In this paper, the development strategiesof shipping centers and transportation networ... It is very important to establish cooperative mechanism to guarantee allmembers to develop their e-conomies in the Yellow Sea Rim. In this paper, the development strategiesof shipping centers and transportation network are discussed based on economic globalizationtendency. The results argue that a united transportation network should be built in order to promotethe economic competition of Northeast Asia in the world. As a key component of the economiccooperation, a hierarchical shipping centers network should be established with Hong Kong, Shanghai,Pusan, Kobe, and Tokyo as cores. The authorities of China, Japan, R. 0. Korea and D. P. R. Koreashould make more efforts to build a set of cooperation institutions based on raising thetransportation efficiency. 展开更多
关键词 the yellow sea rim shipping center transportation network hub-and-spoke system
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Quantum Dots for Cancer Research:Current Status,Remaining Issues,and Future Perspectives 被引量:4
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作者 Min Fang Chun-wei Peng +1 位作者 Dai-Wen Pang Yan Li 《Clinical oncology and cancer researeh》 CAS CSCD 2012年第3期151-163,共13页
Cancer is a major threat to public health in the 21st century because it is one of the leading causes of death worldwide.The mechanisms of carcinogenesis,cancer invasion,and metastasis remain unclear.Thus,the developm... Cancer is a major threat to public health in the 21st century because it is one of the leading causes of death worldwide.The mechanisms of carcinogenesis,cancer invasion,and metastasis remain unclear.Thus,the development of a novel approach for cancer detection is urgent,and real-time monitoring is crucial in revealing its underlying biological mechanisms.With the optical and chemical advantages of quantum dots(QDs),QD-based nanotechnology is helpful in constructing a biomedical imaging platform for cancer behavior study.This review mainly focuses on the application of QD-based nanotechnology in cancer cell imaging and tumor microenvironment studies both in vivo and in vitro,as well as the remaining issues and future perspectives. 展开更多
关键词 quantum dots molecular imaging multimodality probes
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