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Screening Test of Small Seedless Watermelon Varieties in Beijing Area
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作者 Shengqi MU Xuesong YOU +3 位作者 Ying ZHANG Yanli CHEN Chao MA Jin XU 《Agricultural Biotechnology》 CAS 2023年第2期17-19,共3页
[Objectives]This study was conducted to select small seedless watermelon varieties with excellent quality and high yield suitable for planting in Beijing.[Methods]Under the conditions of facility cultivation in Beijin... [Objectives]This study was conducted to select small seedless watermelon varieties with excellent quality and high yield suitable for planting in Beijing.[Methods]Under the conditions of facility cultivation in Beijing,a screening test was conducted on seven small seedless watermelon varieties for growth process,field traits,yield traits,fruit quality,and disease resistance.[Results]Varieties Mitong,Motong and Tianbao Xiaowuzi had a short growth period and relatively stable growth,and bore fruit easily,and their female flowers were closely spaced.Their yields exceeded 60000 kg/hm~2,ranking in the top three among all varieties.The fruit had a thin skin,a bright red flesh color,and a high mass fraction of soluble solids in the center.The flesh was tight or crispy,and tasted good.They also showed good disease resistance.Overall,they showed excellent comprehensive agronomic traits,and are thus suitable for facility cultivation in Beijing and its surrounding areas.[Conclusions]This study provides a theoretical basis for the upgrading of varieties and the increase in production and farmers'income in the suburbs of Beijing. 展开更多
关键词 small seedless watermelon Variety screening Beijing area High yield high quality
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Impact of the Small Town Construction on Original Inhabitants in the Three Gorges Reservoir Area——A Case Study in Lishu Village, Changling Town, Chongqing Municipality, China
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作者 Liu Shao-quan, Chen Guo-jie, Chen Zhi-jianInstitute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, Sichuan, China 《Wuhan University Journal of Natural Sciences》 CAS 2003年第03B期897-904,共8页
Based on the five-year long dynamic tracking and investigation of the peasant households of the Lishu village, the influences by small town construction on the economy and employment of the original peasant households... Based on the five-year long dynamic tracking and investigation of the peasant households of the Lishu village, the influences by small town construction on the economy and employment of the original peasant households are discussed. On the one hand, small town construction plays a positive role in adjustment of the industrial structure of the original peasant households and in the transfer of their employment towards non-agricultural industries. On the other hand the economic growth of the original peasant households is not so well sustainable, and is so fluctuating. Moreover, the unbalance of income distribution of the said households has been furthered, and small town construction has made the existing labor surplus of the original peasant households more serious, particularly the women labor surplus. 展开更多
关键词 the Three Gorges reservoir area small town construction original inhabitant economic income EMPLOYMENT
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Utilization and Management of Small Fishery Population Resources in Coastal and Offshore Areas of China
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作者 Jiahua LE Xiangguo ZHANG Yingqi ZHOU 《Asian Agricultural Research》 2016年第1期30-32,共3页
There are numerous types of living resources in coastal and offshore areas of China. In recent years,both the population type and quantity structure have significant changes,and the stock of small fishery population r... There are numerous types of living resources in coastal and offshore areas of China. In recent years,both the population type and quantity structure have significant changes,and the stock of small fishery population resources is increasing. This population is precious protein resource. It is urgent to study how to take prompt and effective fishing and take full advantage of processing,utilization and management. Traditional utilization methods are limited by many factors. The utilization efficiency is extremely low. The feed conversion rate of some mariculture fishes with fresh small trash fishes as feeds is even as low as 0. 2. Innovative production and management organization model with aquatic enterprises as leaders greatly increases the utilization efficiency of small fish resources with the aid of marine processing mother ship. In order to further accelerate developing and utilizing small fishery population resources in coastal and offshore areas,China should launch survey and utilization researches of small fishery population resources in coastal and offshore areas,formulate practical and feasible laws,regulations and policies,actively encourage and support autonomous innovative management mode of enterprises,and promote effective utilization and management of coastal and offshore fishery resources. 展开更多
关键词 FISHERY POPULATION RESOURCES COASTAL and OFFSHORE areas small FISHERY POPULATION RESOURCES Utilization and management
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Research on Age-friendly Open Spaces Design in Residential Areas of Small Towns
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作者 LI Xiaoyun YI Rong 《Journal of Landscape Research》 2014年第5期8-10,共3页
Taking the accelerating aging and newly promoted urbanization as backdrops, this paper, on one side, analyzed the demands for parks, squares, fi tness facilities, chairs, etc. of elders in small towns from perspective... Taking the accelerating aging and newly promoted urbanization as backdrops, this paper, on one side, analyzed the demands for parks, squares, fi tness facilities, chairs, etc. of elders in small towns from perspectives of unique physical, psychological and social features of elders. On the other side, it also tackled the inadequacies of open spaces in small towns. Moreover, it proposed strategies such as creating social activity spaces, cultivating therapeutic green landscapes, constructing diversely secure fi tness spaces and building age integrated environments, etc. for designing age-friendly open spaces in small towns. 展开更多
关键词 Age-friendly Open Space Residential area small Town
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Mathematical Model of Small Water-plane Area Twin-hull and Application in Marine Simulator 被引量:2
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作者 XiufengZhang Zhenwang Lyu +1 位作者 Yong Yin Yicheng Jin 《Journal of Marine Science and Application》 2013年第3期286-292,共7页
小水飞机区域成双壳(一行) 由于它的好经得起海上风浪的能力引起了许多研究人员的注意。在这份报纸,分离的 MMG 想法被用来执行一行运动建模和模拟;分别地,一行的力量和时刻被划分成赤裸的壳,推进器,在液体水动力学的 rudder,等... 小水飞机区域成双壳(一行) 由于它的好经得起海上风浪的能力引起了许多研究人员的注意。在这份报纸,分离的 MMG 想法被用来执行一行运动建模和模拟;分别地,一行的力量和时刻被划分成赤裸的壳,推进器,在液体水动力学的 rudder,等等。在还原剂插入了相互的干扰在壳之中强迫的系数,和 rudder 的推进器和推进器弄醒系数,为一行的计算,都被考虑。集成的第四顺序的 Runge-Kutta 方法被解决微分方程使用,以便得到一行运动状态。作为一个例子,在全速和海鸥手艺的完整的右舷 rudder 的转弯的测试被显示出。模拟结果显示出一行常规模式和运动的趋势。它验证转弯的运动的数学模型的正确性。一行数学模型被用于海洋的模拟器以便训练飞行员或 seamen,或为海洋工程的安全评价投射。最后,模仿系统(FMNSS ) 的完整的使命航行决心是航行模拟的域里的一件成功的虚拟现实技术应用程序样品。 展开更多
关键词 航海模拟器 数学模型 模型应用 水平面 船体 面积 SWATH 小水线面船
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A Comparison of Hierarchical Bayesian Models for Small Area Estimation of Counts
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作者 Matilde Trevisani Nicola Torelli 《Open Journal of Statistics》 2017年第3期521-550,共30页
Small area estimation (SAE) tackles the problem of providing reliable estimates for small areas, i.e., subsets of the population for which sample information is not sufficient to warrant the use of a direct estimator.... Small area estimation (SAE) tackles the problem of providing reliable estimates for small areas, i.e., subsets of the population for which sample information is not sufficient to warrant the use of a direct estimator. Hierarchical Bayesian approach to SAE problems offers several advantages over traditional SAE models including the ability of appropriately accounting for the type of surveyed variable. In this paper, a number of model specifications for estimating small area counts are discussed and their relative merits are illustrated. We conducted a simulation study by reproducing in a simplified form the Italian Labour Force Survey and taking the Local Labor Markets as target areas. Simulated data were generated by assuming population characteristics of interest as well as survey sampling design as known. In one set of experiments, numbers of employment/unemployment from census data were utilized, in others population characteristics were varied. Results show persistent model failures for some standard Fay-Herriot specifications and for generalized linear Poisson models with (log-)normal sampling stage, whilst either unmatched or nonnormal sampling stage models get the best performance in terms of bias, accuracy and reliability. Though, the study also found that any model noticeably improves on its performance by letting sampling variances be stochastically determined rather than assumed as known as is the general practice. Moreover, we address the issue of model determination to point out limits and possible deceptions of commonly used criteria for model selection and checking in SAE context. 展开更多
关键词 small area Estimation HIERARCHICAL BAYESIAN MODELS Non-Normal Sampling STAGE Unmatched MODELS
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A Simulation Study of Hierarchical Bayesian Fusion Spatial Small Area Model for Binary Outcome under Spatial Misalignment
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作者 Kindie Fentahun Muchie Anthony Kibira Wanjoya Samuel Musili Mwalili 《Open Journal of Statistics》 2021年第6期993-1009,共17页
<p> <span><span style="font-family:""><span style="font-family:Verdana;">Simulation (stochastic) methods are based on obtaining random samples </span><spa... <p> <span><span style="font-family:""><span style="font-family:Verdana;">Simulation (stochastic) methods are based on obtaining random samples </span><span style="color:#4F4F4F;font-family:Simsun;white-space:normal;background-color:#FFFFFF;"><span style="font-family:Verdana;">&theta;</span><sup><span style="font-family:Verdana;">5</span></sup></span><span style="font-family:Verdana;"></span><span style="font-family:Verdana;"> </span><span><span style="font-family:Verdana;"> </span><span><span style="font-family:Verdana;">from the desired distribution </span><em><span style="font-family:Verdana;">p</span></em><span style="font-family:Verdana;">(</span><span style="color:#4F4F4F;font-family:Verdana;white-space:normal;background-color:#FFFFFF;">&theta;</span><span style="font-family:Verdana;"></span><span style="font-family:Verdana;">)</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">and estimating the expectation of any </span></span><span><span style="font-family:Verdana;">function </span><em><span style="font-family:Verdana;">h</span></em><span style="font-family:Verdana;">(</span><span style="color:#4F4F4F;font-family:Verdana;white-space:normal;background-color:#FFFFFF;">&theta;</span><span style="font-family:Verdana;"></span><span style="font-family:Verdana;">)</span><span style="font-family:Verdana;">. Simulation methods can be used for high-dimensional dis</span></span><span style="font-family:Verdana;">tributions, and there are general algorithms which work for a wide variety of models. Markov chain Monte Carlo (MCMC) methods have been important </span><span style="font-family:Verdana;">in making Bayesian inference practical for generic hierarchical models in</span><span style="font-family:Verdana;"> small area estimation. Small area estimation is a method for producing reliable estimates for small areas. Model based Bayesian small area estimation methods are becoming popular for their ability to combine information from several sources as well as taking account of spatial prediction of spatial data. In this study, detailed simulation algorithm is given and the performance of a non-trivial extension of hierarchical Bayesian model for binary data under spatial misalignment is assessed. Both areal level and unit level latent processes were considered in modeling. The process models generated from the predictors were used to construct the basis so as to alleviate the problem of collinearity </span><span style="font-family:Verdana;">between the true predictor variables and the spatial random process. The</span><span style="font-family:Verdana;"> performance of the proposed model was assessed using MCMC simulation studies. The performance was evaluated with respect to root mean square error </span><span style="font-family:Verdana;">(RMSE), Mean absolute error (MAE) and coverage probability of corres</span><span style="font-family:Verdana;">ponding 95% CI of the estimate. The estimates from the proposed model perform better than the direct estimate.</span></span></span></span> </p> <p> <span></span> </p> 展开更多
关键词 Simulation small area Estimation Hierarchical Bayesian Spatial Misalign-ment Fusion Process
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Constructing Statistical Intervals for Small Area Estimates Based on Generalized Linear Mixed Model in Health Surveys
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作者 Yan Wang Xingyou Zhang +2 位作者 Hua Lu Janet B. Croft Kurt J. Greenlund 《Open Journal of Statistics》 2022年第1期70-81,共12页
Generalized Linear Mixed Model (GLMM) has been widely used in small area estimation for health indicators. Bayesian estimation is usually used to construct statistical intervals, however, its computational intensity i... Generalized Linear Mixed Model (GLMM) has been widely used in small area estimation for health indicators. Bayesian estimation is usually used to construct statistical intervals, however, its computational intensity is a big challenge for large complex surveys. Frequentist approaches, such as bootstrapping, and Monte Carlo (MC) simulation, are also applied but not evaluated in terms of the interval magnitude, width, and the computational time consumed. The 2013 Florida Behavioral Risk Factor Surveillance System data was used as a case study. County-level estimated prevalence of three health-related outcomes was obtained through a GLMM;and their 95% confidence intervals (CIs) were generated from bootstrapping and MC simulation. The intervals were compared to 95% credential intervals through a hierarchial Bayesian model. The results showed that 95% CIs for county-level estimates of each outcome by using MC simulation were similar to the 95% credible intervals generated by Bayesian estimation and were the most computationally efficient. It could be a viable option for constructing statistical intervals for small area estimation in public health practice. 展开更多
关键词 Bayesian Estimation Behavioral Risk Factor Surveillance System BOOTSTRAPPING Monte Carlo Simulation small area Estimation
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Determination of Carboplatin Dose by Area Under the Curve in Combination Chemotherapy for Senile Non-small Cell Lung Cancer 被引量:1
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作者 殷铁军 刘菁菁 +1 位作者 胡长耀 刘梦涛 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2007年第6期710-712,共3页
To preliminarily determine the appropriate dosage of carboplatin (CBP) at AUC of 5 mg-M1^-1·min^-1 in the combination chemotherapy for Chinese senile patients with non-small cell lung cancer (NSCLC). Thirty-f... To preliminarily determine the appropriate dosage of carboplatin (CBP) at AUC of 5 mg-M1^-1·min^-1 in the combination chemotherapy for Chinese senile patients with non-small cell lung cancer (NSCLC). Thirty-five Chinese senile patients with NSCLC in advanced stage (Ⅲ/Ⅳ) were given 96 cycles of combination chemotherapy. Chemotherapy schedules included Taxol+CBP, Gemzar+CBP and NVB+CBE The dose of CBP was at 5 mg.mL^-1·min^-1 of area under the concentration-time curve (AUC). Side effects and quality of life were observed before and after the chemotherapy. Myelosuppression was severe and commonly observed. Grade 3/4 of granulocytopenia was found in 47.9% (46/96) of the patients and grade 3/4 of thrombocytopenia was noted in 28.1% (27/96) of the subjects. However, other side effects were slight. The mean score of quality of life (QOL), according to the criteria of QOL for Chinese cancer patients had reduced 6.8. At 5 mg.mL^-1·min^-1 by AUC, the hematological toxicity of CBP was severe and it had some negative effects on the QOL. The administration of CBP at 5 mg.mL^-1·min^-1 by AUC may be too high for Chinese senile patients with non-small cell lung cancer. 展开更多
关键词 senile patients non-small cell lung cancer carboplatin area under the concentration-time curve quality of life
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Resistance and Seakeeping Numerical Performance Analyses of a Semi-Small Waterplane Area Twin Hull at Medium to High Speeds 被引量:1
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作者 Giuliano Vernengo Dario Bruzzone 《Journal of Marine Science and Application》 CSCD 2016年第1期1-7,共7页
新半小的 waterplane 区域双胞胎壳(一行) 的水动力学分析对象小、中等的尺寸旅客渡船那样的各种各样的应用合适被介绍。这可以是源于合并二古典形状的一种吸引人的转线路配置:常规一行和快长筏。最后的壳设计与最大的横梁展出像楔的... 新半小的 waterplane 区域双胞胎壳(一行) 的水动力学分析对象小、中等的尺寸旅客渡船那样的各种各样的应用合适被介绍。这可以是源于合并二古典形状的一种吸引人的转线路配置:常规一行和快长筏。最后的壳设计与最大的横梁展出像楔的吃水线形状在严厉;壳与一个很狭窄的入口角度结束,有典型地代表一行容器的一个突出的球状的弓,并且展示完整对严厉安排 waterjet 推进器。我们与如此的建筑群执行对壳的水动力学表演的一个初步的评价的分析目的在常规头波浪在平静的水和经得起海上风浪的能力里以壳的抵抗塑造两个并且把表演与常规一行的作比较。分析用 preliminarily 在一个常规一行容器上被验证的一个边界元素方法被执行。 展开更多
关键词 小水线面双体船 水动力性能 船体阻力 耐波性 数值分析 高转速 SWATH船 船体设计
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Are the data on quality of life and patient reported outcomes from clinical trials of metastatic non-small-cell lung cancer important?
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作者 Vera Hirsh 《World Journal of Clinical Oncology》 CAS 2013年第4期82-84,共3页
Majority of the patients with advanced non-small-cell lung cancer(NSCLC)experience two or more disease related symptoms,which may have a negative impact on their health-related quality of life(HR QOL).These patients p... Majority of the patients with advanced non-small-cell lung cancer(NSCLC)experience two or more disease related symptoms,which may have a negative impact on their health-related quality of life(HR QOL).These patients prefer a therapy that would improve disease related symptoms,as opposed or treatment that slightly prolongs their survival without improving symptoms.The improvements of the symptoms augment the significance of improved response rates or progression free survivals.The choice of the questionnaires to evaluate patients-reported outcomes(PROs)and HRQOL benefits and methods of collecting the data and their interpretations are very important and are discussed in this manuscript.PROs and HR QOL outcomes are important in patients with advanced NSCLC only when the data are collected and analyzed correctly.Then they can be viewed as components of the total value of a treatment,providing a comprehensive picture of the benefits and risks of anticancer therapies.Enabling the patients to feel during the last months of their lives more comfortable and not be dependent on their loved ones is a very important task in the treatment of advanced NSCLC. 展开更多
关键词 Quality of life Clinical trials NON-small cell LUNG cancer Patient reported OUTCOMES
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Lateral bearing characteristics of subsea wellhead assembly in the hydrate trial production engineering
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作者 Jing Zeng Wen-wei Xie +8 位作者 Bei-bei Kou Jing-an Lu Xing-chen Li De-jun Cai Hao-xian Shi Ke-wei Zhang Hua-qing Liu Jin Li Bo Li 《China Geology》 CAS CSCD 2023年第3期455-465,共11页
Conductor and suction anchor are the key equipment providing bearing capacity in the field of deep-water drilling or offshore engineering,which have the advantages of high operation efficiency and short construction p... Conductor and suction anchor are the key equipment providing bearing capacity in the field of deep-water drilling or offshore engineering,which have the advantages of high operation efficiency and short construction period.In order to drill a horizontal well in the shallow hydrate reservoir in the deep water,the suction anchor wellhead assembly is employed to undertake the main vertical bearing capacity in the second round of hydrate trial production project,so as to reduce the conductor running depth and heighten the kick-off point position.However,the deformation law of the deep-water suction anchor wellhead assembly under the moving load of the riser is not clear,and it is necessary to understand the lateral bearing characteristics to guide the design of its structural scheme.Based on 3D solid finite element method,the solid finite element model of the suction anchor wellhead assembly is established.In the model,the seabed soil is divided into seven layers,the contact between the wellhead assembly and the soil is simulated,and the vertical load and bending moment are applied to the wellhead node to simulate the riser movement when working in the deep water.The lateral bearing stability of conventional wellhead assembly and suction anchor wellhead assembly under the influence of wellhead load is discussed.The analysis results show that the bending moment is the main factor affecting the lateral deformation of the wellhead string;the anti-bending performance from increasing the outer conductor diameter is better than that from increasing the conductor wall thickness;for the subsea wellhead,the suction anchor obviously improves the lateral bearing capacity and reduces the lateral deformation.The conduct of the suction anchor wellhead assembly still needs to be lowered to a certain depth that below the maximum disturbed depth to ensure the lateral bearing stability,Thus,a method for the minimum conductor running depth for the suction anchor wellhead assembly is developed.The field implementations show that compared with the first round of hydrate trial production project,the conductor running depth is increased by 9.42 m,and there is no risk of wellhead overturning during the trial production.The method for determining the minimum conductor running depth in this paper is feasible and will still play an important role in the subsequent hydrate exploration and development. 展开更多
关键词 Natural gas hydrate Deep-water Subsea wellhead Suction anchor Wellhead stability 3D solid finite element method Hydrate trial exploration engineering Natural gas hydrate trial production Shenhu area The South China Sea
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基于HS-Small模型临江深基坑降水变形特性分析 被引量:1
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作者 黄建华 李瑞 《水电能源科学》 北大核心 2023年第11期116-120,203,共6页
临江深基坑工程地下水随江水位变化呈现长期水位低、汛期水位高的动态特征,坑内降水导致周围地层渗流场趋于复杂,易引发围护结构破坏、坑底管涌和基坑失稳等工程事故。为此,采用基于HS-Small本构模型对深基坑工程的开挖-降水过程进行模... 临江深基坑工程地下水随江水位变化呈现长期水位低、汛期水位高的动态特征,坑内降水导致周围地层渗流场趋于复杂,易引发围护结构破坏、坑底管涌和基坑失稳等工程事故。为此,采用基于HS-Small本构模型对深基坑工程的开挖-降水过程进行模拟,分析了降水影响因素(降水深度、方式、速率和止水帷幕)对周围环境变形的敏感性及其相互之间的关系,并将分析结果与实测结果进行对比验证。结果表明,随临江深基坑土方开挖和降水进行,基坑坡顶、坑外土体和周边建筑物沉降变形逐渐增大,其中降水对基坑变形影响更明显;分次降水能有效降低周围建筑物和地表的沉降变形;降水深度建议控制在底板以下0.5~2.0 m;降水速率对周围环境沉降总量影响相对较小,但对沉降速率影响较大,当降水速率达到最优值时对基坑稳定性控制有益;止水帷幕嵌入深度超过30 m后对控制周围建筑沉降效果不明显。研究结果可为类似临江深基坑降水工程设计施工提供借鉴和参考。 展开更多
关键词 临江工程 HS-small本构模型 开挖降水 沉降机理 软土地区
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Estimating Poverty in Greece in Small Geographical Areas
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作者 Stefanos G. Giakoumatos Malapani Eleni 《Journal of Statistical Science and Application》 2017年第1期16-29,共14页
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2012—2022年北京市石景山区肺结核流行特征分析
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作者 张亚敬 任丽君 +3 位作者 王明良 姜影 周琳 唐桂琴 《结核与肺部疾病杂志》 2024年第2期158-163,共6页
目的:分析2012—2022年北京市石景山区肺结核流行特征,为以后更好开展结核病防治工作提供科学依据。方法:通过“中国疾病预防控制信息系统”的子系统“结核病信息管理系统”,收集2012—2022年北京市石景山区肺结核患者相关资料,包括性... 目的:分析2012—2022年北京市石景山区肺结核流行特征,为以后更好开展结核病防治工作提供科学依据。方法:通过“中国疾病预防控制信息系统”的子系统“结核病信息管理系统”,收集2012—2022年北京市石景山区肺结核患者相关资料,包括性别、年龄、职业、病原学情况、现住址等,采用描述性流行病学方法进行统计分析。结果:2012—2022年石景山区共报告肺结核患者1954例,年均报告发病率为28.60/10万。肺结核报告发病率由2012年的35.70/10万(231例)下降到2022年的21.85/10万(123例),总体呈下降趋势(χ^(2)_(趋势)=40.035,P<0.001)。报告肺结核患者中,男性1288例,女性666例,性别比为1.93∶1,男性报告发病率(37.44/10万,1288/3 440 000)高于女性(19.63/10万,666/3 392 000),差异有统计学意义(χ^(2)=189.416,P<0.001)。0~14岁、15~64岁、≥65岁3个年龄组肺结核报告发病率分别为2.76/10万(19/688 973)、25.69/10万(1372/5 341 527)和69.21/10万(563/813 409),≥65岁年龄组报告发病率明显高于0~14岁和15~64岁年龄组,差异有统计学意义(χ^(2)=647.183,P<0.001)。职业分布前5位的是离退休人员(33.88%,662/1954)、家务及待业(21.19%,414/1954)、干部职员(9.88%,193/1954)、工人(8.55%,167/1954)、学生及教师(6.14%,120/1954)。第2季度报告肺结核患者例数最多(26.36%,515/1954),其次是第4季度(25.03%,489/1954),第1季度(23.80%,465/1954)最少。结论:2012—2022年北京市石景山区肺结核报告发病率总体呈下降趋势,≥65岁老年人是石景山区肺结核防控的重点人群,应采取有效措施,尽早发现老年患者,及时采取治疗措施。 展开更多
关键词 结核 流行病学研究 综合预防 小地区分析
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小区域尺度视角下的丽江市玉河健康特征研究
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作者 周彦辰 芮茂刚 +2 位作者 许斌 申其明 周筱妍 《三峡大学学报(自然科学版)》 CAS 北大核心 2024年第3期23-28,共6页
随着社会发展,工业化、城镇化进程不断加快,河湖生态问题日益突出且呈现更复杂的发展态势,进行河湖健康评价,开展河湖健康问题诊断,针对性地提出河湖生态系统精准治理、生态修复与保护等对策显的尤为迫切.结合丽江市典型河流玉河,以水... 随着社会发展,工业化、城镇化进程不断加快,河湖生态问题日益突出且呈现更复杂的发展态势,进行河湖健康评价,开展河湖健康问题诊断,针对性地提出河湖生态系统精准治理、生态修复与保护等对策显的尤为迫切.结合丽江市典型河流玉河,以水域岸线状况、水量水质状况、生物状况、社会服务功能等4个准则层为重要抓手,构建11个指标层的河流健康评价体系,将玉河划分为农村段、城镇段、复合段3个小区域尺度进行综合评价,探讨了小区域尺度河流健康评价差异性特征,研究表明:玉河全河段、各分段均处于亚健康状态,玉河农村段、复合段、各城镇段岸线部分指标层、准则层间健康状况差异性显著,主要存在水资源禀赋差,生态流量小,底栖动物少,局部岸线状况较差的问题. 展开更多
关键词 河流健康评价 准则层 指标层 小区域尺度
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龙门山双复杂区表层结构调查方法研究
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作者 刘远志 刘胜 +4 位作者 黄秀举 梁勇 陈兵 王聪 张志锋 《物探化探计算技术》 CAS 2024年第3期306-314,共9页
龙门山山前带地表地质条件复杂,浅表层速度及厚度差异大,给激发、接收和静校正等工作带来较大困难。表层调查工作直接影响到地下介质成像效果。为使该地区进行的地震勘探攻关能够获取准确的静校正量数据,给井深设计提供依据,研究适合该... 龙门山山前带地表地质条件复杂,浅表层速度及厚度差异大,给激发、接收和静校正等工作带来较大困难。表层调查工作直接影响到地下介质成像效果。为使该地区进行的地震勘探攻关能够获取准确的静校正量数据,给井深设计提供依据,研究适合该区域的表层调查方法,结合地质剖面、浅震、小层析、地面微测井、钻井取心、高密度电法、三分量共振表层调查方法的工作原理,分别应用不同方法做比对,分析了不同调查方法的应用效果。通过不同表层调查的比对,分析了不同方法的适用范围,为该区选择合适的表层调查方法及方法参数选取提供依据,同时为其他地表复杂区域进行表层调查提供参考。 展开更多
关键词 双复杂区 表层结构 地质调查 浅震 小层析 微测井 钻井取心 高密度电法 三分量共振
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组合光透视下小面积室内封闭空间分割方法
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作者 赵会宾 张立 《激光杂志》 CAS 北大核心 2024年第5期231-235,共5页
为提高室内空间的优化规划设计能力,提出基于点云数据语义分割的组合光透视下小面积室内封闭空间分割方法。构建小面积室内封闭空间的环境三维信息感知模型,采用室内空间点云提取室内封闭空间图像的坐标信息,结合语义组合特征分割方法... 为提高室内空间的优化规划设计能力,提出基于点云数据语义分割的组合光透视下小面积室内封闭空间分割方法。构建小面积室内封闭空间的环境三维信息感知模型,采用室内空间点云提取室内封闭空间图像的坐标信息,结合语义组合特征分割方法将融合空间信息映射到高分辨空间异质单元结构中,引入几何约束的子空间投影特征信息,结合组合光透视的高分辨率分割图模型参数融合方法,提取小面积室内封闭的端元,采用点云数据语义分割方法实现空间分割。结果表明,采用该方法有效实现对复杂室内场景的三维重建,空间分割的均方根误差较低为0.808%,峰值信噪比较高42.156 dB,空间分割速度较快,平均为12.83 ms。 展开更多
关键词 组合光透视 小面积 室内封闭空间 分割 语义组合特征分割
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心律失常与起搏领域临床研究2023年度进展
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作者 吴寸草 李学斌 《中国介入心脏病学杂志》 CSCD 2024年第1期20-23,共4页
回顾2023年心律失常领域重要临床试验,涉及心房颤动(房颤)、起搏等方面。CIRDADOSE研究及EARLY-AF研究均肯定冷冻球囊消融治疗房颤疗效,减慢房颤进展。MANIFEST-PF研究回顾房颤脉冲场消融的成功率及安全性,在ADVENT研究中再次证实其安... 回顾2023年心律失常领域重要临床试验,涉及心房颤动(房颤)、起搏等方面。CIRDADOSE研究及EARLY-AF研究均肯定冷冻球囊消融治疗房颤疗效,减慢房颤进展。MANIFEST-PF研究回顾房颤脉冲场消融的成功率及安全性,在ADVENT研究中再次证实其安全性和有效性不劣于传统热消融。在左束支区域起搏(LBBAP)研究中,与双心室起搏(BVP)相比,LBBAP降低持续性室性心动过速(VT)/心室颤动(VF)和新发房颤发生率。对于起搏比例高且射血分数降低的起搏器或植入式心律转复除颤器(ICD)患者,BUDAPEST CRT升级研究肯定了其升级到心脏再同步除颤器(CRT-D)的明确获益。DANPACEⅡ研究显示窦房结功能障碍患者的心房起搏最小化并不能降低房颤的发生率。IDE研究显示Aveir DR双腔无导线起搏器术后3个月安全性良好,可提供可靠的心房起搏和房室同步。iSUSI研究是对皮下植入式心律转复除颤器的注册研究,发现心力衰竭和非心力衰竭患者不恰当和恰当电击率相似。 展开更多
关键词 临床试验 心房颤动 冷冻球囊消融 脉冲场消融 左束支区域起搏 CRT升级 无导线起搏器 植入式除颤器
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四川盆地中部地区震旦系大型碳酸盐岩气藏开发技术新进展
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作者 闫海军 杨长城 +11 位作者 郭建林 刘曦翔 曹正林 杨东凡 王忠楠 邓惠 张钰祥 杨山 季丽丹 王丽珍 夏钦禹 郑国强 《天然气工业》 EI CAS CSCD 北大核心 2024年第5期68-79,共12页
四川盆地中部地区(以下简称川中地区)震旦系灯影组气藏为大型古老深层岩溶风化壳型碳酸盐岩气藏,气藏整体表现为低孔隙度低渗透率,储集空间小尺度缝洞发育,储层非均质性强特征,气藏开发面临储层表征难、井位部署和效益开发难度大等系列... 四川盆地中部地区(以下简称川中地区)震旦系灯影组气藏为大型古老深层岩溶风化壳型碳酸盐岩气藏,气藏整体表现为低孔隙度低渗透率,储集空间小尺度缝洞发育,储层非均质性强特征,气藏开发面临储层表征难、井位部署和效益开发难度大等系列挑战。为此,以川中地区安岳气田灯影组气藏为对象,通过地质工程一体技术化攻关,深化了对储层发育特征和成因机理的认识,提出了气藏开发新模式,创建形成了气藏高效开发的关键技术。研究结果表明:①灯影组储层主要为岩溶成因储层,具有“叠合岩溶差异控储”的发育特征;②岩溶储层非均质性强,“溶蚀相成因控储”可精细刻画储层的非均质性;③灯影组气藏宜采用“单井指标叠加论证气藏规模”的开发新模式;④创新形成了“双界面”岩溶古地貌恢复及定量刻画方法,并指导平面选区,其中Ⅰ+Ⅱ类井比例由评价期的40%提高到方案建设期的100%;⑤创建了小尺度缝洞识别、刻画及表征技术,并指导钻井轨迹设计,测试百万立方米气井比例由开发评价期的41.6%提高到建产期的60%;⑥配套完善了分段酸压工艺技术,高效动用了优质储层,并解放了低品位储层,储层渗透率由改造前的0.62 mD提高到酸压改造后的6.77 mD。结论认为,“十四五”期间,在上述开发技术的支持下,安岳气田由台缘带灯四段高效开发转向长期稳产和台内地区多层系效益开发,蓬莱含气区由单井高产转向区块高产和气藏规模建产,将强力支撑中国石油西南油气田公司“十四五”末天然气上产500×10^(8)m^(3)。 展开更多
关键词 川中地区 安岳气田 蓬莱含气区 震旦系 小尺度缝洞 叠合岩溶 溶蚀相 双界面法
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