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基于UPLC-Zone TOF-MS/MS联合网络药理学探讨脉复生防治NAFLD作用
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作者 胡涛 王冰钰 +5 位作者 苏薇薇 彭维 黎建华 李常青 周毅业 郭洁文 《中山大学学报(自然科学版)(中英文)》 CAS CSCD 北大核心 2024年第5期73-82,共10页
依据脉复生的化学成分,采用网络药理学、分子对接技术、构建NAFLD小鼠模型,探究脉复生防治NAFLD的作用机制。通过UPLC-Zone TOF-MS/MS对脉复生全成分进行检测;借助Swiss生物信息学研究平台获取活性成分和靶点,在OMIM、Disgenet数据库筛... 依据脉复生的化学成分,采用网络药理学、分子对接技术、构建NAFLD小鼠模型,探究脉复生防治NAFLD的作用机制。通过UPLC-Zone TOF-MS/MS对脉复生全成分进行检测;借助Swiss生物信息学研究平台获取活性成分和靶点,在OMIM、Disgenet数据库筛选NAFLD疾病靶点,对交集靶点进行PPI分析;在Metascape网站进行GO与KEGG富集分析,对核心靶点与活性成分展开分子对接;采用HFD诱导C57BL/6J小鼠构建NAFLD模型进行核心靶点验证;指认得到130个化学成分,筛选得到54个活性成分与176个可能作用于NAFLD的潜在靶点;根据Degree值对排名前10的成分与靶点进行分子对接实验,对结合能最优的对接模型TNF与Quercetin、IL-17与Asiatic acid、IL-1β与Quercetin进行可视化分析;筛选炎症因子和脂肪代谢相关基因进行qPCR测序。富集分析表明脉复生治疗NAFLD与脂肪酸转化、脂质代谢正向调节等生物过程相关,涉及AGE-RAGE、HIF-1、IL-17等信号通路;与对照组相比,模型组血清学检测ALT、TG、LDL-C指标上升并且HDL-C指标下降(P<0.05);与模型组相比,脉复生给药组和辛伐他汀组能够降低小鼠体质量、肝脏和脂肪质量占比(P<0.05),降低血清中TNF-α、IL-1β和IL-17的含量和mRNA表达,在高剂量时具有显著性差异(P<0.01);与对照组相比,脉复生给药组能够通过调节脂质代谢相关基因的表达,降低肝脏脂质堆积,缓解肝脏脂肪变性。 展开更多
关键词 UPLC-zone TOF-MS/MS 脉复生 非酒精性脂肪肝 网络药理学 实验验证
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Spherizone工艺多区反应器内聚丙烯结块的问题 被引量:1
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作者 李金扬 《广东化工》 CAS 2024年第2期60-62,共3页
介绍了Spherizone工艺的原理,指出了采用该工艺生产的主要聚丙烯(PP)产品与采用传统工艺生产的主要PP相比的优势和生产控制过程中的技术难点。分析了反应器内物料结块的主要原因是高活性细粉黏结、静电结块和反应器内PP物料循环不充分... 介绍了Spherizone工艺的原理,指出了采用该工艺生产的主要聚丙烯(PP)产品与采用传统工艺生产的主要PP相比的优势和生产控制过程中的技术难点。分析了反应器内物料结块的主要原因是高活性细粉黏结、静电结块和反应器内PP物料循环不充分造成的。重点提出了开工前清理反应器,合理控制反应器下降段柱塞流,优化出料阀振荡程序,控制物料循环速率、Atmer163型抗静电剂以及反应器制造质量等是避免反应器内物料结块的关键。 展开更多
关键词 聚丙烯 多区反应器 结块 催化剂活性 循环
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Twenty-Three Years of Insect Pollinator-Dependent Crop Studies in Agro-Ecological Zones of Cameroon (2011-2020)
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作者 Népidé Ndobadé Carine Egono Ndemé Carole Christèle +1 位作者 Daniel Farda Mazi Sanda 《Agricultural Sciences》 2024年第8期877-908,共32页
Cultivation of pollinator-dependent crops has expanded globally, increasing our reliance on insect pollination. This essential ecosystem service is provided by a wide range of managed and wild pollinators whose abunda... Cultivation of pollinator-dependent crops has expanded globally, increasing our reliance on insect pollination. This essential ecosystem service is provided by a wide range of managed and wild pollinators whose abundance and diversity are thought to be in decline, threatening sustainable food production. In Cameroon, several studies on pollinator-dependent crops carried out in different agro-ecological zones (AEZ) have been published in national and international journals, in order to present the importance and impact of flowering insects on fruit and seed yields of plant species. We proposed to produce a review article highlighting the different flowering insects and their importance for different plants according to AEZ, without however focusing on the quality of the journal (predator or non-predator) and how the different insects were identified (scientific names given in the publications). Thus, from 1997 to 2020, we collected 116 published papers from which only 26 were kept for this review. The results show that Hymenoptera, including the Apidae, followed by Megachilidae, are the most excellent pollinators of plant species in Cameroon, and they are present in different agro-ecological zones. The majority of publications focused on bees, particularly the honeybee Apis mellifera. 展开更多
关键词 Agro-Ecological zones Cameroon Flowering Insects HYMENOPTERA POLLINATORS
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Cameroon Climate Predictions Using the SARIMA-LSTM Machine Learning Model: Adjustment of a Climate Model for the Sudano-Sahelian Zone of Cameroon
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作者 Joseph Armathé Amougou Isidore Séraphin Ngongo +2 位作者 Patrick Forghab Mbomba Romain Armand Soleil Batha Paul Ghislain Poum Bimbar 《Open Journal of Statistics》 2024年第3期394-411,共18页
It is acknowledged today within the scientific community that two types of actions must be considered to limit global warming: mitigation actions by reducing GHG emissions, to contain the rate of global warming, and a... It is acknowledged today within the scientific community that two types of actions must be considered to limit global warming: mitigation actions by reducing GHG emissions, to contain the rate of global warming, and adaptation actions to adapt societies to Climate Change, to limit losses and damages [1] [2]. As far as adaptation actions are concerned, numerical simulation, due to its results, its costs which require less investment than tests carried out on complex mechanical structures, and its implementation facilities, appears to be a major step in the design and prediction of complex mechanical systems. However, despite the quality of the results obtained, biases and inaccuracies related to the structure of the models do exist. Therefore, there is a need to validate the results of this SARIMA-LSTM-digital learning model adjusted by a matching approach, “calculating-test”, in order to assess the quality of the results and the performance of the model. The methodology consists of exploiting two climatic databases (temperature and precipitation), one of which is in-situ and the other spatial, all derived from grid points. Data from the dot grids are processed and stored in specific formats and, through machine learning approaches, complex mathematical equations are worked out and interconnections within the climate system established. Through this mathematical approach, it is possible to predict the future climate of the Sudano-Sahelian zone of Cameroon and to propose adaptation strategies. 展开更多
关键词 Adjustment CALIBRATION CLIMATE Sudano-Sahelian zone Numerical Model
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Disparities in Prevalence and Determinants of Hypertension amongst Bamiléké Adults Residing in Two Different Agroecological Zones of Cameroon
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作者 Maxwell Wandji Nguedjo Nanhah Kamga Jules Vidal +7 位作者 Alice Louise Woguia Pauline Vervaine Hagbe David Goda Dany Joël Ngassa Ngoumen Hippolyte Tene Mouafo Boris Gabin Kingue Azantsa Judith Laure Ngondi Julius Enyong Oben 《Open Journal of Epidemiology》 2024年第3期419-443,共25页
Background: Cardiovascular diseases such as hypertension (HTN) are one of the main causes of death in Cameroon. This study aimed at assessing prevalence disparities and determinants of hypertension amongst Bamilé... Background: Cardiovascular diseases such as hypertension (HTN) are one of the main causes of death in Cameroon. This study aimed at assessing prevalence disparities and determinants of hypertension amongst Bamiléké adults residing in two different agroecological zones of Cameroon. Methods: A cross-sectional and descriptive survey was conducted among Bamiléké population living in the Highlands zone (Western region) and in the Monomodal Rainforest zone (Littoral region) of Cameroon from August 2016 to August 2017. Participants (962) were aged at least 20 years old. Data on sociodemographic, hemodynamic, anthropometric, and biochemical parameters and lifestyle of the participants were collected. Results: Results obtained revealed that 34.2% were hypertensive and those residing in the highland zone were more affected than those living in the monomodal rainforest zone (44.5% vs 22.9%). The different subtypes of HTN (Isolated systolic hypertension (14.1%), isolated diastolic hypertension (7.2%) and Systo-diastolic hypertension (23.3%)) were also more prevalent in the Highlands Zone. The most prevalent stage of HTN was pre-HTN (31.5%). However, people living in the monomodal rainforest zone were more affected by pre-HTN compared to Bamiléké living in the highland zone (33.6% vs. 29.6%). Results also showed that high consumption (≥ 3 times/week) of carbohydrate- and fat-rich foods, ageing, obesity, and marital status were associated with high blood pressure in both agroecological zones. Besides, secondary education (OR = 0.68;95% CI: 0.42 - 0.99) in the Highlands Zone and high (≥3 times/week) vegetable consumption (OR = 0.66;95% CI: 0.44 - 0.98) in the Monomodal Rainforest Zone had a protective effect on elevated blood pressure of population. Conclusion: There is a disparity in the prevalence of hypertension and some of its determinants among Bamiléké adults residing in different agroecological zones. This work highlights the need to advocate for local and ethno-cultural health policies to prevent, diagnose and manage hypertension. 展开更多
关键词 HYPERTENSION DISPARITIES Determinants Bamiléké Ethnic Group Agroecological zone
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基于Spherizone工艺的聚丙烯产品结块问题浅析及对策
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作者 宋晓辉 《化工生产与技术》 CAS 2024年第3期34-37,42,I0004,共6页
针对Spherizone工艺中多区反应器内物料结块问题,通过分析静电结块、物料循环不充分、下降段吹扫不合理、反应器出料控制阀响应时间设定不合理、反应器内局部丙烯液化和单体原料含杂质、催化剂活性突变等6个方面的主要原因,提出了相应... 针对Spherizone工艺中多区反应器内物料结块问题,通过分析静电结块、物料循环不充分、下降段吹扫不合理、反应器出料控制阀响应时间设定不合理、反应器内局部丙烯液化和单体原料含杂质、催化剂活性突变等6个方面的主要原因,提出了相应的改善措施。其中,包括调整Atmer163的流量、增加静电仪和超声波检测装置、优化出料控制阀响应时间、监控提升段压差等措施。通过这些措施的综合应用,可以有效地减少结块问题,提高反应器的稳定性和生产效率。 展开更多
关键词 SPHERIzone工艺 聚丙烯 产品结块 多区反应器
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Ultrasound Ranging with Selective Zone
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作者 Libo Deng 《World Journal of Engineering and Technology》 2024年第2期339-361,共23页
The technology of ultrasonic measurement has been widely applied in many fields in recent years. It has already been researched for almost 40 years and its application in both residential use and military are mature a... The technology of ultrasonic measurement has been widely applied in many fields in recent years. It has already been researched for almost 40 years and its application in both residential use and military are mature and well-developed. One of the advanced uses is for reversing a car and it is based on sending sound waves through a specific medium and observing the returning echoes to measure the distance from the device to the obstacle. In this report, a simple ultrasonic distance measurement system will be introduced including the design of hardware and software, the simulating results and the final product. This system was built to be cheaper, requires less power and delivers better performance. 展开更多
关键词 ULTRASOUND Selective zone
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Semantic Segmentation of the Intertidal Zone of an Estuary—In Search of the Best Solution
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作者 Maria da Conceição Proença Ricardo Nogueira Mendes Ricardo Melo 《Journal of Geoscience and Environment Protection》 2024年第7期1-13,共13页
An aerial photographic coverage acquired on two consecutive days in October 2021 with a ground resolution of 20 cm and a spectral resolution of 4 bands (red, green, blue and near infrared), allowed to distinguish most... An aerial photographic coverage acquired on two consecutive days in October 2021 with a ground resolution of 20 cm and a spectral resolution of 4 bands (red, green, blue and near infrared), allowed to distinguish most of the classes of interest present in the intertidal zone of the Sado estuary. We explored the possibilities of thematic classification in the powerful and complex software ArcGIS Pro;we presented the methodology used in a detailed way that allows others with minimal knowledge of GIS to reproduce the classification process without having to decipher the specifics of the software. The classification implemented used ground truth from four classes related to the macro-occupations of the area. In a first phase we explore the standard algorithms with object-based capabilities, like K-Nearest Neighbor, Random Trees Forest and Support Vector Machine, and in a second phase we proceed to test three deep learning classifiers that provide semantic segmentation: a U-Net configuration, a Pyramid Scene Parsing Network and DeepLabV3. The resulting classifications were quantitatively evaluated with a set of 500 control points in a test area of 37,500 × 12,500 pixels, using confusion matrices and resorting to Cohen’s kappa statistic and the concept of global accuracy, achieving a Kappa in the range [0.72, 0.81] and a global accuracy between 88.9% and 92.9%;the option U-Net had the most interesting results. This work establishes a methodology to provide a baseline for assessing future changes in the distribution of Sado estuarine habitats, which can be replicated in other wetland ecosystems for conservation and management purposes. 展开更多
关键词 ESTUARY Intertidal zone ArcGIS Pro SEGMENTATION Global Changes
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Comparative Study of the Types of Photovoltaic Panels Used in Solar Pumping Systems in Dry Tropical Zones: Case of Adamawa Region in Cameroon
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作者 Boussaibo Andre Waoudowa Kande Veronique +1 位作者 Ndjiya Ngasop Stephane Gautier Kitmo 《Open Journal of Energy Efficiency》 2024年第3期79-87,共9页
In the dry tropical zone where access to water is increasingly difficult for populations, solar pumping units are increasingly installed to provide water to population. In the local market, there are essentially two t... In the dry tropical zone where access to water is increasingly difficult for populations, solar pumping units are increasingly installed to provide water to population. In the local market, there are essentially two types of solar panels, namely monocrystalline and polycrystalline. However, the part of the local market is more dominated by the polycrystalline panel. In this work, comparative studies are carried out in order to characterize the two types of solar panels with regard to local constraints. Tests were carried out over the course of the sun to establish the performance of each type. The panels used have the same electrical characteristics and are connected to loads with same characteristics. Under the set operating conditions, the monocrystalline panel presents more performance than the polycrystalline panel. Although the local market is dominated by the polycrystalline panel, dust deposition tests on the surface of the panels show that the performance of the polycrystalline panel is more affected compared to the performance of the monocrystalline panel. 展开更多
关键词 Solar Pumping Monocrystalline Cell Polycrystalline Cell Dry tropical zone Dustdeposit
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Acceptability of Immunization against COVID-19 by the Populations of the Kasenga State Health Area in the Uvira Health Zone, DR Congo
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作者 Derrick Bushobole Akiba Eric Amuri Madabali +11 位作者 Robert Bushambale Fataki Abel Asende Luhendama Jacques Mutono Matongo Faustin Bukuru Mudage Christian Banyakwa Mitunda Saili Stay Mushobekwa Michel Byaombe Wa Ngene Martin Longolongo Kiza Paulin Mulogoto Rushanika Emmanuel Nirambo Rujanjika Henry Manya Mboni Criss Koba Mjumbe 《Journal of Immune Based Therapies, Vaccines and Antimicrobials》 2024年第3期33-46,共14页
Introduction: COVID-19 was an emerging disease putting all public health systems in countries around the world in a state of emergency. To be able to prevent its spread and morbidity and mortality, several appropriate... Introduction: COVID-19 was an emerging disease putting all public health systems in countries around the world in a state of emergency. To be able to prevent its spread and morbidity and mortality, several appropriate strategies were necessary, such as vaccination. The latter has been the subject of controversy. The objective of the present study is therefore to evaluate the factors associated with the acceptance of this vaccine within the population of the Kasenga State Health Area. A result which will shed light on future strategies to be put in place for possible new vaccines. Methodology: Is a prospective and analytical cross-sectional study conducted over a period of approximately 1 month from January 5 to February 5, 2024. A survey questionnaire in Kobotoolbox was useful for collecting data. STATA software was very important for us in analyzing the data collected. Results: Prevalence of vaccination against COVID-19 among the population of the Kasenga State Health Area is 37.5% (28.4 - 45.6). The study revealed that reluctance is observed among most of the population for different reasons, including, first and foremost, the deliberate aspect of not wanting to take the vaccine (46.6%) and rumors that this antigen is dangerous and harmful (32.9%). 72.5% of respondents believe that the COVID-19 vaccine is a fabrication, unhealthy and that the disease itself never existed. The study proved that there was a statistical relationship between age (p = 0.001) and adherence to vaccination. And the refusal of respondents to recommend the vaccine to loved ones was a factor associated with non-adherence to vaccination (OR = 7.901, 95% IC [3.028 - 20.615], p = 0.000). Conclusion: Vaccination against COVID-19 was not well accepted by the population of the study site. Raising public awareness and involving community leaders and political-administrative authorities, which has not been done well, would play an important role in the good perception of the disease, of the vaccine and therefore in its adherence. 展开更多
关键词 COVID-19 Vaccination Kasenga State Health Area Associated Factors Uvira Health zone City of Uvira
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Spatial Variability of Microclimate Characteristics in Transition Zone of the Forest: A Case Study of Slătioara Secular Forest
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作者 Marius Dan Șandru 《Open Journal of Forestry》 2024年第4期369-396,共28页
Although the importance of forest margins in ecology is recognized, no study has been carried out in the Slătioara Secular Forest Reserve with reference to the variability of abiotic parameters along forest margins. W... Although the importance of forest margins in ecology is recognized, no study has been carried out in the Slătioara Secular Forest Reserve with reference to the variability of abiotic parameters along forest margins. With this study, we investigate to what extent microclimatic variables (air temperature—T_air, air humidity—H_air, soil temperature—T_soil, soil humidity—H_soil wind intensity (WIND) and photosynthetically active radiation intensity (PAR)) are correlated with the distance from the edge to the forest interior and the habitat type (forest interior, inner and outer edge and meadow) in the Slătioara Secular Forest Reserve. In order to measure these microenvironment variables we used the strip transect method, positioned perpendicular to the forest edge. Differences in the microenvironment variables considered in the analysis between the four habitat types were assessed using one-way ANOVA followed by Tukey-test post-hoc. To assess differences along transects, each of the six measurements went through a one-way ANOVA against distance to edge, followed by a Levene’s test for variances and finally a Tukey-test post-hoc. The results indicate that the values of microclimatic variables were significantly different in relation to the gradient of distance from the edge and to the habitat type (interior-exterior forest) and that edge habitats are significantly more susceptible to lower humidity, high winds, lower light and higher air temperatures than forest interior habitats. The ecological study of the edge areas in this reserve provides the basis for future research on forest dynamics and can guide conservation efforts to maintain the diversity and endemism of species in the Slătioara Secular Forest. 展开更多
关键词 Component Forest Microclimate Edge Effects Edge-Interior Relationships Forest Buffer zone Edge Influence Microclimatic Influences
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开发区升格政策能促进企业创新增量提质吗?
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作者 张帅 王筱依 《太原学院学报(社会科学版)》 2025年第1期92-106,共15页
通过构建多时点DID模型实证检验开发区升格政策对企业创新数量和创新质量的影响,结果表明:省级开发区升格通过降低制度性交易成本、提升市场化程度和加速创新要素流入对企业创新产出数量和产出质量产生促进作用,该政策对非民营企业、非... 通过构建多时点DID模型实证检验开发区升格政策对企业创新数量和创新质量的影响,结果表明:省级开发区升格通过降低制度性交易成本、提升市场化程度和加速创新要素流入对企业创新产出数量和产出质量产生促进作用,该政策对非民营企业、非高技术制造行业、高新区和小规模城市的作用效果更强。因此,要充分发挥开发区“以升促建”的创新激励效应,不仅要注重有为政府和有效市场的结合,还要根据城市固有经济特征优化开发区制度环境。 展开更多
关键词 开发区升格 创新数量 创新质量
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Assessing current faulting behaviors and seismic risk of the Anninghe-Zemuhe fault zone from seismicity parameters 被引量:100
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作者 易桂喜 闻学泽 +1 位作者 范军 王思维 《地震学报》 CSCD 北大核心 2004年第3期294-303,共10页
Using the data of regional seismic network, this paper analyzes the current faulting behaviors of different segments of the Anninghe-Zemuhe fault zone, western Sichuan, and identifies the likely risky segments for pot... Using the data of regional seismic network, this paper analyzes the current faulting behaviors of different segments of the Anninghe-Zemuhe fault zone, western Sichuan, and identifies the likely risky segments for potential large earthquakes. The authors map the probable asperities from the abnormally low b-value distribution, develop and employ a method for identifying current faulting behaviors of individual fault segment from the combinations of multiple seismicity parameter values, and make an effort to estimate the average recurrence intervals of character-istic earthquakes by using the parameters of magnitude-frequency relationship of the asperity segment. The result suggests that the studied fault zone contains 5 segments of different current faulting behaviors. Among them, the Mianning-Xichang segment of the Anninghe fault has been locked under high stress, its central part is probably an asperity with a relatively large scale. The Xichang-Puge segment of the Zemuhe fault displays very low seismicity under low stress. Both the locked segment and the low-seismicity segment can be outlined on the across-profile of relocated hypocenter depths. The Mianning-Xichang segment is identified to be the one with potential large earth-quake risk, for which the average recurrence interval between the latest M = 6.7 earthquake in 1952 and the next characteristic event is estimated to be 55 to 67 years, and the magnitude of the potential earthquake between 7.0 and 7.5. Also, it has been preliminarily suggested that for a certain fault segment, its faulting behaviors may change and evolve with time gradually. 展开更多
关键词 地震活动参数 断裂活动 习性 凹凸体潜在地震危险性 安宁河—则木河断裂带
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基于TrustZone的可信移动终端云服务安全接入方案 被引量:28
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作者 杨波 冯登国 +1 位作者 秦宇 张英骏 《软件学报》 EI CSCD 北大核心 2016年第6期1366-1383,共18页
可信云架构为云计算用户提供了安全可信的云服务执行环境,保护了用户私有数据的计算与存储安全.然而在移动云计算高速发展的今天,仍然没有移动终端接入可信云服务的安全解决方案.针对上述问题,提出了一种可信移动终端云服务安全接入方案... 可信云架构为云计算用户提供了安全可信的云服务执行环境,保护了用户私有数据的计算与存储安全.然而在移动云计算高速发展的今天,仍然没有移动终端接入可信云服务的安全解决方案.针对上述问题,提出了一种可信移动终端云服务安全接入方案.方案充分考虑了移动云计算应用背景,利用ARM Trust Zone硬件隔离技术构建可信移动终端,保护云服务客户端及安全敏感操作在移动终端的安全执行.结合物理不可克隆函数技术,给出了移动终端密钥与敏感数据管理机制.在此基础上,借鉴可信计算技术思想设计了云服务安全接入协议.协议兼容可信云架构,提供云服务端与移动客户端间的端到端认证.分析了方案具备的6种安全属性,给出了基于方案的移动云存储应用实例,实现了方案的原型系统.实验结果表明:可信移动终端TCB较小,方案具有良好的可扩展性和安全可控性,整体运行效率较高. 展开更多
关键词 移动云计算 可信计算 可信移动终端 安全接入 Trust zone 物理不可克隆函数(PUF)
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Holocene activities of the Taigu fault zone, Shanxi Province, and their relations with the 1303 Hongdong M=8 earthquake 被引量:21
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作者 谢新生 江娃利 +1 位作者 王焕贞 冯西英 《地震学报》 CSCD 北大核心 2004年第3期281-293,共13页
The Taigu fault zone is one of the major 12 active boundary faults of the Shanxi fault-depression system, located on the eastern boundary of the Jinzhong basin. As the latest investigation indicated, the fault zone ha... The Taigu fault zone is one of the major 12 active boundary faults of the Shanxi fault-depression system, located on the eastern boundary of the Jinzhong basin. As the latest investigation indicated, the fault zone had dislocated gully terrace of the first order, forming fault-scarp in front of the loess mesa. It has been discovered in many places in ground surface and trenches that Holocene deposits were dislocated. The latest activity was the 1303 Hongdong earthquake M=8, the fault appeared as right-lateral strike-slip with normal faulting. During that earthquake, the Taigu fault together with the Mianshan western-side fault on the Lingshi upheaval and the Huoshan pediment fault on the eastern boundary of the Linfen basin was being active, forming a surface rupture belt of 160 km in length. Moreover, the Taigu fault were active in the mid-stage of Holocene and near 7 700 aB.P. From these we learnt that, in Shanxi fault-depression system, the run-through activity of two boundary faults of depression-basins might generate great earthquake with M=8. 展开更多
关键词 太谷断裂 全新世活动 1303年洪洞地震 地表破裂带
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永久基本农田保护片区智能识别系统iZone的建立与应用 被引量:6
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作者 马世发 吴楷钊 +3 位作者 劳春华 钟远军 张婷 黄韬 《农业工程学报》 EI CAS CSCD 北大核心 2017年第2期276-282,共7页
永久基本农田划定是当前国土资源管理一项十分重要而紧迫的任务,其对维护粮食安全和控制城镇无序增长具有重要意义。永久基本农田划定不仅要满足耕地质量较高而且还要集中连片,更需要协调城镇化矛盾。因此,如何从土地利用现状数据库中... 永久基本农田划定是当前国土资源管理一项十分重要而紧迫的任务,其对维护粮食安全和控制城镇无序增长具有重要意义。永久基本农田划定不仅要满足耕地质量较高而且还要集中连片,更需要协调城镇化矛盾。因此,如何从土地利用现状数据库中提取永久基本农田保护图斑实际上是一个复杂的空间数据挖掘过程。研究利用农用地分等成果定义保护片区质量,利用元胞自动机模拟分析土地利用矛盾,利用种子扩充算法进行保护片区搜索,利用神经网络进行耕地保护压力预警。基于C#和Arc Engine10.1将多种空间数据挖掘模型进行集成,构成了面向全域永久基本农田识别的智能系统工具包iZone,并在广东省高要区金利镇进行实例应用。研究表明,iZone能按既定规则从土地利用现状数据库中提取保护图斑,有效避免了人为划定的过多主观性,并且能获得与人工方案相当乃至更好的表现。iZone利用复杂地理计算技术进行永久基本农田智能识别,可提高永久基本农田划定工作的科学性。 展开更多
关键词 土地利用 区划 识别 永久基本农田 农用地利用等别 元胞自动机 种子搜索 人工神经网络
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KarstHyporheicZone及其研究进展 被引量:5
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作者 蒲俊兵 袁道先 《中国岩溶》 CAS CSCD 2013年第1期7-13,共7页
Karst Hyporheic Zone(笔者将之译为"岩溶交互带")是近三年来新出现的一个岩溶术语,我国尚未开展"岩溶交互带"的研究工作,它主要是指岩溶地下水与周边岩溶基质(含沉积物、基岩)水之间物质能量活跃交替的地带。本文... Karst Hyporheic Zone(笔者将之译为"岩溶交互带")是近三年来新出现的一个岩溶术语,我国尚未开展"岩溶交互带"的研究工作,它主要是指岩溶地下水与周边岩溶基质(含沉积物、基岩)水之间物质能量活跃交替的地带。本文从"岩溶交互带"的概念来源、含义、最新的研究进展和监测技术发展等方面进行了总结,并就现存的问题和未来研究提出了看法。 展开更多
关键词 “岩溶交互带” 岩溶术语 科学意义
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基于联合熵隐私保护的自适应动态Mix-zone方案 被引量:4
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作者 冯霞 刘亚伟 《通信学报》 EI CSCD 北大核心 2018年第3期76-85,共10页
针对车联网中Mix-zone方案灵活性低以及隐私保护程度对用户缺乏透明度的问题,提出一种交通自适应的动态Mix-zone创建方法,可以根据道路交通状况为车辆动态创建Mix-zone,随时随地为车辆创建Mix-zone进行假名更换,建立基于身份和位置的隐... 针对车联网中Mix-zone方案灵活性低以及隐私保护程度对用户缺乏透明度的问题,提出一种交通自适应的动态Mix-zone创建方法,可以根据道路交通状况为车辆动态创建Mix-zone,随时随地为车辆创建Mix-zone进行假名更换,建立基于身份和位置的隐私保护;提出对Mix-zone进行隐私分级的联合熵度量模型,可通过归一化的定量计算结果度量Mix-zone达到当前区域车辆隐私需求的程度。使用深圳市某区的出租车辆的轨迹数据验证了联合熵隐私度量模型及基于该模型的Mix-zone创建方案,实验结果表明,该联合熵模型能刻画交通场景中参数与隐私保护程度的正比关系,在联合熵所表示的无序性指标上,所提Mix-zone创建方案相较其他方案,具有更好的隐私保护效果。 展开更多
关键词 车联网 Mix-zone 联合熵 隐私保护
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短周期线性密集台阵揭示宣城地区浅部地壳速度结构及断裂发育特征
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作者 方捷 姚华建 +2 位作者 李杰 李俊伦 周桂理 《地球与行星物理论评(中英文)》 2025年第2期201-214,共14页
宣城市位于东南丘陵与长江中下游平原过渡地带,区内经历多期构造活动,地质构造复杂且断裂十分发育,开展宣城地区浅部速度结构和断裂带探测,不仅有助于深入了解区内地质构造和成矿作用,还可以为区域地震危险性和危害性评价提供重要的参... 宣城市位于东南丘陵与长江中下游平原过渡地带,区内经历多期构造活动,地质构造复杂且断裂十分发育,开展宣城地区浅部速度结构和断裂带探测,不仅有助于深入了解区内地质构造和成矿作用,还可以为区域地震危险性和危害性评价提供重要的参考模型.本文在研究区布设了一条由110套三分量地震仪组成的短周期线性密集台阵,利用采集的一个月的三分量背景噪声数据,采用噪声谱比方法(HVSR)探测研究区场地峰值频率及基岩界面结构;通过垂直分量背景噪声数据重建经验格林函数,采用拓距相移法(ERPS)提取相速度频散曲线并反演线性台阵下方浅部地壳精细横波速度结构.基于HVSR计算的场地峰值频率和基岩界面埋深,刻画了测线下方浅部地表松散沉积层的结构,结果显示研究区内皖南山区基岩埋深较浅,盆地区域基岩埋深较深,地表松散沉积层的厚度最大可至地下80 m,此外还评估了区内地震破坏性和建筑的抗震性,认为研究区内平均振幅放大系数相对较高,局部区域可能会产生明显的地震放大效应,并且皖南山区低矮建筑(1~2层)及宣城—南陵盆地区域的高层建筑(7层及以上)在抗震设防上应当特别注意;依据反演的二维横波速度模型,获得了研究区浅部地壳6 km以深的结构,结果显示宣城—南陵盆地在浅部表现为明显的低速特征,其基底深度可达2 km,并且盆地部分区域呈现相对高速的异常特征,指示在区域多期构造活动中产生的岩浆侵入和逆冲推覆构造作用。此外,区内深部总体表现为高低速异常交替分布的“叠瓦状”构造模式,出现的多处低速异常带推断分别是周王断裂、江南断裂和茅山断裂以及清水河—河湾断裂的构造破碎带,指示了研究区内经历的多期次挤压—拉伸的强烈变形改造.综合上述研究成果,本研究为宣城地区地质构造条件的分析、地震危险性及危害性的评价以及区域找矿勘查等相关工作提供了新的依据. 展开更多
关键词 背景噪声成像 H/V谱比 拓距相移 地壳浅层结构 断裂带探测 地震灾害预防
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Planning and Design of "Garden City" in the North Zone of Qionglai City in China 被引量:1
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作者 李俊 刘琨 《Journal of Landscape Research》 2011年第6期1-4,9,共5页
By taking the north zone of Qionglai City constructing "world modern garden city" for example, the paper analyzed the concept of garden city, location situation and development of Qionglai City. After analys... By taking the north zone of Qionglai City constructing "world modern garden city" for example, the paper analyzed the concept of garden city, location situation and development of Qionglai City. After analysis of tourist location advantage of Qionglai City, the vital significance for overall layout of urban landscape was emphasized. Furthermore, strategies for concept planning of the north zone of Qionglai City had been illustrated from the perspectives of landscape shaping, ecological landscape and green land system structure. It emphasized that the overall landscape should be guided by "city in the field and garden in the city", pay attention to co-existence between ecological group garden and aggregation group, and highlight resources advantage of collection area of ecological landscapes. In terms of landscape shaping, it stressed unity, ecology, regionality and character. In terms of characteristic creation, discussion had been conducted from three aspects which were garden city demonstration line, residential landscape and waterfront shoreline. It emphasized that, during construction of world modern garden city, it should make the main line of city image clear, respect culture; well deal with the relations between city and village, between human and environment, and between function and image; and build livable ecological urban place, so as to protect environment, explore city feature and build city image. 展开更多
关键词 NORTH zone of Qionglai CITY World MODERN GARDEN CITY CITY LANDSCAPE
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