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Constructing Index System for Evaluating Work Level in Rural Endowment Insurance
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作者 ZHAO Zhigang WANG Yalin 《Journal of Northeast Agricultural University(English Edition)》 CAS 2008年第3期90-96,共7页
This paper used fuzzy math principles, analyzed different aspects of the work of the current rural endowment insurance and formed the indices to assess the work level of the rural endowment insurance. After selecting ... This paper used fuzzy math principles, analyzed different aspects of the work of the current rural endowment insurance and formed the indices to assess the work level of the rural endowment insurance. After selecting the indices of the work level scientificly, constructed the index system to evaluate the work level of the rural endowment insurance and the index system was expressed in the form of math equation. In this way, an objective standard used to evaluate the work level of rural endowment insurance was establised. 展开更多
关键词 rural endowment insurance work level index system
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Relationship between glutathione and malonaldehyde levels in erythrocytes and the deformation index of erythrocyte in patients at various periods following acute cerebral infarction 被引量:2
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作者 Dongjun Zhang Guangrun Xu +1 位作者 Zhaofu Chi Bingxia Shi 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第1期64-66,共3页
BACKGROUND: Glutathione, as an in vivo free radical scavenger, plays an important role in the anti-oxidation defense mechanism in patients with acute cerebral infarction. OBJECTIVE: To observe the relationship betwe... BACKGROUND: Glutathione, as an in vivo free radical scavenger, plays an important role in the anti-oxidation defense mechanism in patients with acute cerebral infarction. OBJECTIVE: To observe the relationship between the levels of glutathione (GSH) and malonaldehyde (MDA), the metabolite of lipid peroxidation, in erythrocyte and deformation index of erythrocyte in patients at various periods following acute cerebral infarction. DESIGN: Controlled observation.SETTING: Qilu Hospital of Shandong University and Institute of Cerebrovascular Disease of Qingdao Medical College. PARTICIPANTS: We chose 98 inpatients with acute cerebral infarction from Department of Neurology, Qilu Hospital of Shandong University from January to December 2000 , serving as cerebral infarction group, including 50 male and 48 female, with mean age of (62±7)years. There were 23 cases found on the 1^st day after onset; 25 cases on the 3^rd day after onset; 25 cases on the 7^th day after onset; 25 cases on the 14th days after onset, and they were all confirmed by craniocerebral CT or MRI. Another 30 homeochronous inpatients with neurosis, cervical syndrome, lumbar intervertebral disc herniation and motor neuron disease were chosen as control group, including 20 male and 10 female, with mean age of (52±8)years . There was no significant difference in age and gender distribution between two groups (P 〉 0.05). Patients in the two groups were informed of detected index.METHODS:①Ulnar venous blood was chosen from the patients who were fasted on the 1^st, 3^rd,7^th and 14^th days after onset. Deformation index of erythrocyte was measured with BL88-CKX laser diffraction erythrocyte deformeter and photographing was performed. GSH level in erythrocyte was measured with DTNB assay introduced by Beu-tler. MDA level in erythrocyte was measured with modified thiobarbituric acid colorimetric method.②At each sample collecting , according to the criteria accepted by the Fourth National Conference of Cerebrovascular Disease, intergrant of neurologic impairment 〈 15 points was regarded as mild (n=46), 15 to 30 points as moderate (n=40)and, 〉 30 points as severe (n=12). ③ t test was used to compare data between two groups , and linear correlation analysis was used in relationship analysis among indexes. MAIN OUTCOME MEASURES :① Comparison of erythrocyte GSH and MDA levels and deformation index of erythrocyte at various periods between patients with acute cerebral infarction and controls. ②Correlation of erythrocyte GSH level with erythrocyte MDA level and with deformation index of erythrocyte in patients with cerebral infarction . ③ Relationship between erythrocyte GSH level and severity of disease in patients with acute cerebral infarction. RESULTS: Totally 98 patients with acute cerebral infarction and 30 controls all entered the stage of result analysis. ① Erythrocyte GSH level and deformation index of erythrocyte were lower on the 1^st, 3^rd, 7^th and 14^th days after onset in cerebral infarction group than in control group (P 〈 0.05-0.01), and erythrocyte MDA level was significantly higher in cerebral infarction group than in control group (P 〈 0.05-0.01). The three indexes changed most significantly on day 3 after onset in patients, and began to recover or decrease on day 7 after onset and inclined to be normal on day 14 after onset. ② Erythrocyte GSH level was significantly negatively correlated with erythrocyte MDA level in patients with acute cerebral infarction on the 1^st, 3^rd, 7^th and 14^th days after onset (r=-0.534, -0.713, -0.645, -0.656, respectively, P 〈 0.05-0.01 ) ,and significantly positively correlated with erythrocyte deformation index (t-=0.502, 0.560, 0.455, 0.504, respectively, P 〈 0.05). ③Erythrocyte GSH level was significantly lower in moderate or severe patients with acute cerebral infarction than in mild patients[(0.215±0.088),(0.192±0.102), (0.281±0.090) g/L, P〈 0.05]. CONCLUSION:①Erythrocyte GSH and MDA levels and deformation index of erythrocyte change significantly on the 3^rd day following acute cerebral infarction. Index detection results gradually tended to be normal on from the 7^th day to 14^th days day after onset. ② Change of erythrocyte GSH level can reflect the severity of disease of patients with acute cerebral infarction.③Decrease of erythrocyte GSH level in patients with acute cerebral infarction is one of reasons that result in the decrease of deformation ability of erythrocyte. 展开更多
关键词 Relationship between glutathione and malonaldehyde levels in erythrocytes and the deformation index of erythrocyte in patients at various periods following acute cerebral infarction
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Application of Security Index in Evaluation of Agricultural Insurance Security Level
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作者 Xuan ZUO Qiao ZHANG Ke WANG 《Asian Agricultural Research》 2018年第2期39-41,共3页
At present,there is still no unified standard for evaluation of agricultural insurance security level,especially in the quantitative evaluation. In order to explore a scientific and reasonable evaluation method for ag... At present,there is still no unified standard for evaluation of agricultural insurance security level,especially in the quantitative evaluation. In order to explore a scientific and reasonable evaluation method for agricultural insurance security level,this paper analyzed the current situation of evaluation methods of social insurance,endowment insurance and medical insurance,as well as the application of security index. It is expected to provide a certain reference for evaluation of agricultural insurance security level by the agricultural insurance security index. 展开更多
关键词 Agricultural Insurance Security level EVALUATION Security index
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Mathematical Index for Evaluating Disperse Dyes Levelness of Superfine Polyester Fabric
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作者 王晶 董振礼 王宁 《Journal of China Textile University(English Edition)》 EI CAS 2000年第2期61-64,共4页
The dyeing deference between the superfine and the con-ventional polyester fabric is discussed. The major threefactors affecting the level dyeing property of superfinepolyester-initial adsorption rate, desorption rate... The dyeing deference between the superfine and the con-ventional polyester fabric is discussed. The major threefactors affecting the level dyeing property of superfinepolyester-initial adsorption rate, desorption rate andinterface migration rate of dyestuffs at 70℃ are studied.The levelness improves considerably with decreased ini-tial adsorption rate, increased desorption rate and inter-face migration rate. And then a mathematical indexbased on them is established. The evaluation to dispersedyes resulting from it corresponds with their perfor-mance during industrial process. As new definitions, ini-tial adsorption rate and desorption rate of dyestuffs arefirstly introduced. 展开更多
关键词 superfine POLYESTER fabric level DYEING property disperse dye MATHEMATICAL index for EVALUATING levelNESS .
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HCSIM:一种长期高频Block-Level快照索引技术 被引量:9
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作者 吴广君 云晓春 +2 位作者 方滨兴 王树鹏 余翔湛 《计算机学报》 EI CSCD 北大核心 2009年第10期2080-2090,共11页
高频快照技术应用于备份时,能够为物理错误和人为错误提供数据保护,构建可靠数据存储环境.针对长期、高频block-level快照检索效率低下问题,在对目前常见的block-level快照技术建模、分析基础上,提出结合数据分布特征和检索模式的分层... 高频快照技术应用于备份时,能够为物理错误和人为错误提供数据保护,构建可靠数据存储环境.针对长期、高频block-level快照检索效率低下问题,在对目前常见的block-level快照技术建模、分析基础上,提出结合数据分布特征和检索模式的分层次二维索引结构——HCSIM.实验、分析结果表明:HCSIM索引技术应用于长期、高频快照管理时,比时空索引结构Overlapping B+Tree索引技术显著提高索引的存储效率和检索效率;通过定性的分析,HCSIM是目前存在的block-level快照索引模式中存储效率和检索效率相对平衡的索引技术. 展开更多
关键词 快照 安全存储 索引 灾难恢复 块数据
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Change of Low-level Jet in a Heavy Rainstorm Process of Xiangtan in July 2016 被引量:1
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作者 Dai Jin He Ning +1 位作者 Chen Si Lin Mingli 《Meteorological and Environmental Research》 CAS 2019年第2期10-14,共5页
Based on the previous research on the model of rainstorm weather with low-level jet in Xiangtan,using the classification result of radar echo characteristics,the wind profile data provided by new generation of weather... Based on the previous research on the model of rainstorm weather with low-level jet in Xiangtan,using the classification result of radar echo characteristics,the wind profile data provided by new generation of weather radar in Changsha and hourly rainfall data,a thorough study of the heavy rainfall from 2 to 5 July 2016 in Xiangtan was conducted. It was concluded that heavy precipitation had the characteristics of the WPSH pattern of rainstorm with low-level jet at early stage,and then it converted to cold shear jet pattern in latter stage. When low-level southwest jet began to have momentum download,that is to say,there was more than 12 m/s of southwest jet below 1 km,and it rapidly strengthened and expanded downward,it was conducive to the occurrence of short-term rainstorm. The low-level jet would not immediately cause a strong precipitation when it reached the station,with a certain lag. A positive correlation existed between the increase of low-level jet index and precipitation intensity,and low-level jet index could predict the occurrence of heavy rainfall and rain intensity. 展开更多
关键词 RAINSTORM Low-level JET index WIND PROFILE product Xiangtan
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Dry Matter Partitioning and Harvest Index Differ in Rice Genotypes with Variable Rates of Phosphorus and Zinc Nutrition 被引量:7
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作者 Amanullah Inamullah 《Rice science》 SCIE CSCD 2016年第2期78-87,共10页
Phosphorus (P) and zinc (Zn) deficiencies are the major problems that decrease crop productivity under rice-wheat cropping system. Field experiments were conducted to investigate impacts of P (0, 40, 80 and 120 k... Phosphorus (P) and zinc (Zn) deficiencies are the major problems that decrease crop productivity under rice-wheat cropping system. Field experiments were conducted to investigate impacts of P (0, 40, 80 and 120 kg/hm^2) and Zn levels (0, 5, 10 and 15 kg/hm^2) on dry matter (DM) accumulation and partitioning, and harvest index of three rice genotypes 'fine (Bamati-385) vs. coarse (F-Malakand and Pukhraj)' at various growth stages (tiliering, heading and physiological maturity). The experiments were conducted at farmers' field at Batkhela in Northwestern Pakistan for two years in summer 2011 and 2012. The two year pooled data reveled that there were no differences in percent of DM partitioning into leaves and culms with application of different P and Zn levels, and genotypes at tillering. The highest P level (120 kg/hm^2) partitioned more DM into panicles than leaves and culms at heading and physiological maturity stages. The highest Zn level (15 kg/hm^2) accumulated more DM and partitioned more DM into panicles than leaves and culms at heading and physiological maturity stages. The hybrid rice (Pukhraj) produced and partitioned more DM into panicles than F-Malakand and Bamati-385 at heading and physiological maturity stages. Higher DM accumulation and greater amounts of partitioning into panicles at heading and physiological maturity stages was noticed with increase in P and Zn levels, and the increase was significantly higher in the coarse rice genotypes than fine. We concluded that the growing hybrid rice with application of 120 kg/hm^2 P + 15 kg/hm^2 Zn not only increases total DM accumulation and partitioned greater amounts into the reproductive plant parts (panicles) but also results in higher harvest index. 展开更多
关键词 dry matter partitioning growth stage harvest index phosphorus level RICE zinc level
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Evaluation of regional water resources carrying capacity based on binary index method and reduction index method 被引量:13
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作者 Hong-yuan Fang Sheng-wei Gan Chen-ying Xue 《Water Science and Engineering》 EI CAS CSCD 2019年第4期263-273,共11页
Based on the regional water resources carrying capacity(WRCC)evaluation principles and evaluation index system in the National Technical Outline of Water Resources Carrying Capacity Monitoring and Early Warning(hereaf... Based on the regional water resources carrying capacity(WRCC)evaluation principles and evaluation index system in the National Technical Outline of Water Resources Carrying Capacity Monitoring and Early Warning(hereafter referred to as the Technical Outline),this paper elaborates on the collection and sorting of the basic data of water resources conditions,water resources development and utilization status,social and economic development in basins,analysis and examination of integrity,consistency,normativeness,and rationality of the basic data,and the necessity of WRCC evaluation.This paper also describes the technique of evaluating the WRCC in prefecture-level cities and city-level administrative divisions in the District of the Taihu Lake Basin,which is composed of the Taihu Lake Basin and the Southeastern River Basin.The evaluation process combines the binary index evaluation method and reduction index evaluation method.The former,recommended by the Technical Outline,uses the total water use and the amount of exploited groundwater as evaluation indices,showing stronger operability,while the latter is developed by simplifying and optimizing the comprehensive index system with greater systematicness and completeness.The mutual validation and adjustment of the results of the above-mentioned two evaluation methods indicate that the WRCC of the District of the Taihu Lake Basin is overloaded in general because some prefecture-level cities and city-level administrative divisions in the Taihu Lake Basin and the Southeastern River Basin are in a severely overloaded state.In order to explain this conclusion,this paper analyzes the causes of WRCC overloading from the aspects of basin water environment,water resources development and utilization,water resources regulation and control ability,water resources utilization efficiency,and water resources management. 展开更多
关键词 Water resources carrying capacity(WRCC) EVALUATION Binary index method Reduction index method Prefecture-level cities and city-level administrative divisions
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Evaluating the Impact of Different Tillage Regimes and Nitrogen Levels on Yield and Yield Components of Maize (Zea mays L.) 被引量:1
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作者 Muhammad Naeem Shahid M. Shahid Ibni Zamir +5 位作者 Ihtisham-Ul Haq M. Kamran Khan Mazhar Hussain Usman Afzal M. Asim Ihtisham Ali 《American Journal of Plant Sciences》 2016年第6期789-797,共9页
A field study to evaluate the impact of different tillage regimes and nitrogen levels on yield and yield components of maize (Zea mays L.), was conducted during autumn 2014 at Students Farm, Department of Agronomy, Un... A field study to evaluate the impact of different tillage regimes and nitrogen levels on yield and yield components of maize (Zea mays L.), was conducted during autumn 2014 at Students Farm, Department of Agronomy, University of Agriculture, Faisalabad. The experiment was laid out in RCBD (Randomized Complete Block Design), with split plot arrangement having three replications. The experiment was comprised of three tillage regimes (Minimum, Conventional and Deep) and three nitrogen levels viz: 100, 200 and 300 kg&bull;ha<sup>-1</sup>. Urea was used as a source of nitrogen, sulphate of potash as a source of potassium and triple super phosphate as a source of phosphorous. The amount of phosphorous and potash was constant in all the treatments i.e. 125 kg&bull;ha<sup>-1</sup> and 100 kg&bull;ha<sup>-1</sup> respectively. Results of present study are summarized as yield parameters are significantly affected by different nitrogen levels and tillage regimes. Maximum number of plants at harvest (7.93), number of grain rows per cob (17.70), number of grains per row (34.31), number of grains per cob (678.58), and cob weight (187.50 g) were observed in deep tillage at 200 kg&bull;ha<sup>-1</sup> nitrogen application. 1000-grain weight (275.52 g), biological yield (15.66 t&bull;ha<sup>-1</sup>), grain yield (6.16 t&bull;ha<sup>-1</sup>) and dried stalk yield (9.91 t&bull;ha<sup>-1</sup>) were observed maximum in deep tillage at 200 kg&bull;ha<sup>-1</sup> nitrogen application. Harvest index significantly affected by tillage regimes and maximum harvest index (39.58%) were recorded in deep tillage which was statistically at par with conventional tillage (38.83%). It was concluded that higher grain yield of maize can be obtained by deep tillage with the application of 200 kg&bull;ha<sup>-1</sup> nitrogen application under the prevailing conditions of Faisalabad. 展开更多
关键词 Tillage Regimes Nitrogen levels Deep Tillage Biological Yield Harvest index
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伤害感受水平指数指导瑞芬太尼输注靶浓度对接受乳腺癌根治术患者细胞免疫和缺氧诱导因子-1α的影响
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作者 詹银周 陈俊衡 +3 位作者 陈超 蔡楚源 马学珠 郭春明 《实用医学杂志》 CAS 北大核心 2024年第18期2566-2570,共5页
目的探讨伤害感受水平(NOL)指数应用于乳腺癌根治术对患者的细胞免疫和缺氧诱导因子(HIF)-1α的影响。方法招募2022年12月至2023年12月行乳腺癌根治术的80例患者,随机将患者分为观察组和对照组。观察组控制NOL指数在30~50,依此调整瑞芬... 目的探讨伤害感受水平(NOL)指数应用于乳腺癌根治术对患者的细胞免疫和缺氧诱导因子(HIF)-1α的影响。方法招募2022年12月至2023年12月行乳腺癌根治术的80例患者,随机将患者分为观察组和对照组。观察组控制NOL指数在30~50,依此调整瑞芬太尼靶浓度,对照组起始采用瑞芬太尼4 ng/mL靶控输注,依据血流动力学调整瑞芬太尼靶浓度。记录瑞芬太尼平均靶浓度;记录手术前1 d及手术后1 d患者的静脉血CD4^(+)、CD8^(+)以及NK细胞值,测定血清中HIF-1α水平。结果两组患者的麻醉时间、手术时间、术中MAP、HR、丙泊酚靶浓度和术后VAS评分均差异无统计学意义(P>0.05),观察组术中的瑞芬太尼平均靶浓度低于对照组(P<0.05);在术后1 d,观察组的CD4^(+)、CD4^(+)/CD8^(+)、NK细胞值均高于对照组,HIF-1α水平低于对照组(P<0.05)。相比术前1 d,观察组患者在术后1 d的CD4^(+)、CD4^(+)/CD8^(+)较低,HIF-1α水平较高(P<0.05);相比术前1 d,对照组患者在术后1天的CD4^(+)、CD8^(+)、CD4^(+)/CD8^(+)及NK细胞值较低,HIF-1α水平较高(P<0.05)。结论NOL指数应用于全麻下乳腺癌根治术可以减少术中瑞芬太尼的靶浓度,降低瑞芬太尼对细胞免疫的抑制,保护NK细胞的活性,同时减少HIF-1α升高水平,由此推断对患者肿瘤免疫微环境的影响更小。 展开更多
关键词 伤害感受水平指数 乳腺癌根治术 细胞免疫 瑞芬太尼 缺氧诱导因子-1Α
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基于长时间序列的中东大西洋渔获物平均营养级及资源状况变化分析
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作者 张忠 韩冠荣 +2 位作者 李楠 方舟 陈新军 《海洋渔业》 CSCD 北大核心 2024年第2期151-165,共15页
为了解中东大西洋渔业产区渔获物的资源状况,根据世界粮农组织(FAO)提供的该海域1950—2019年的渔获量数据,结合渔获种类的平均营养级(mean trophic level,MTL)信息,运用统计学方法分析70年间渔获物平均营养级和营养级平衡指数(fishing ... 为了解中东大西洋渔业产区渔获物的资源状况,根据世界粮农组织(FAO)提供的该海域1950—2019年的渔获量数据,结合渔获种类的平均营养级(mean trophic level,MTL)信息,运用统计学方法分析70年间渔获物平均营养级和营养级平衡指数(fishing in balance,FiB)的变动规律,以掌握该海域渔业资源的可持续利用情况。结果显示,MTL大致可分为4个阶段,1950—1956年,MTL指数在3.20左右,无明显变化;1957—1963年,MTL指数迅速上升至3.44;1964—1996年,MTL在波动中趋于下降,历史最高值(3.54)出现在1985年;1997—2019年,MTL稳定在较高水平,其中2018年为该阶段最低点3.35。FiB指数整体呈上升趋势,1950—1956年,FiB指数呈小幅波动增加;1957—1974年,FiB指数显著上升;1975—1996年,FiB指数呈平稳波动状态;1997—2019年,FiB指数整体呈小幅增长趋势。结果表明,中东大西洋海洋生态系统相对稳定,但潜在的渔业资源量越来越少,开发潜力有限。 展开更多
关键词 中东大西洋 渔业资源 平均营养级 FiB指数
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基于多级索引表的金融业务数据库精准查询方法
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作者 何远景 李光龙 《安阳工学院学报》 2024年第2期60-64,共5页
为提升金融业务数据库查询精准度和效率,设计了一种基于多级索引表的金融业务数据库精准查询方法。首先,构建多级索引的逻辑结构,设计多级索引表构建过程;其次,进行金融业务数据特征融合,为金融业务数据查询准备好数据条件;最后,设计金... 为提升金融业务数据库查询精准度和效率,设计了一种基于多级索引表的金融业务数据库精准查询方法。首先,构建多级索引的逻辑结构,设计多级索引表构建过程;其次,进行金融业务数据特征融合,为金融业务数据查询准备好数据条件;最后,设计金融业务数据库精准查询算法,完成基于多级索引表的金融业务数据库精准查询方法设计的全过程。实验结果表明:设计方法的金融业务数据库查询精准度均在90%以上,最高可达到98%,而且查询所需时间最短仅为5.25 s。本设计方法的适用性极强,具有较好的应用前景,以期能够为金融业务数据的精准高效查询提供参考借鉴。 展开更多
关键词 多级索引表 金融业务 数据库 数据查询 精准查询
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我国省域中等职业教育综合发展水平差异比较、均衡水平与协调性分析——基于PLS结构方程模型的实证研究
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作者 李德显 史晓谭 《职业技术教育》 北大核心 2024年第21期58-67,共10页
中等职业教育高质量发展是推动我国建立现代职业教育体系的重要基础。以2021年我国31个省(区、市)教育宏观统计数据为基础,构建由入学机会、发展规模、教育质量、经费投入、办学条件5个一级指标构成的中等职业教育综合发展水平评价指标... 中等职业教育高质量发展是推动我国建立现代职业教育体系的重要基础。以2021年我国31个省(区、市)教育宏观统计数据为基础,构建由入学机会、发展规模、教育质量、经费投入、办学条件5个一级指标构成的中等职业教育综合发展水平评价指标体系,采用PLS结构方程模型的方法对我国中职教育综合发展水平进行测评。研究结论如下:我国中等职业教育综合发展水平存在着贡献率差异与相关性差异的内部结构不均衡性;我国中等职业教育综合发展水平省域间差异较大,综合水平普遍不高,“金字塔”式结构特征明显;除北京、天津和吉林外,我国各省市中等职业教育均具有非均衡发展特征,且我国省域中等职业教育发展内外协调性较差。为提高我国中等职业教育发展水平,可以采取以下策略:因地制宜控制中等职业教育发展规模,加强教育质量内涵建设;非均衡发展省份补齐自身短板,促进中等职业教育优质协调发展;完善中等职业教育投入支撑体制,为中职教育发展提供坚实保障。 展开更多
关键词 中等职业教育 综合发展水平 指标体系 均衡水平 协调程度
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中国新质生产力的发展水平和演进趋势 被引量:2
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作者 高怡冰 任沛阳 陈钰鑫 《科技管理研究》 CSSCI 2024年第14期47-58,共12页
新质生产力的测算是研究新质生产力发展水平的基础,但当前关于新质生产力的评价指标体系和测度方法尚处于探索阶段。鉴于新质生产力是质和量的统一、能力和效率的统一、现实性和可比性的统一,依据生产力理论,结合高质量发展的现实要求,... 新质生产力的测算是研究新质生产力发展水平的基础,但当前关于新质生产力的评价指标体系和测度方法尚处于探索阶段。鉴于新质生产力是质和量的统一、能力和效率的统一、现实性和可比性的统一,依据生产力理论,结合高质量发展的现实要求,以及新质生产力在科技创新、要素提升、生产组织等方面的特征,系统分析新质生产力的本质要求、构成要素、实现途径、培育载体和支撑环境,在此基础上构建包括技术、要素、数字、产业和环境五维度的指标体系,对中国30个省份2022—2022年的新质生产力发展水平进行测度,并分析其发展格局和演进趋势。结果表明:30个省份新质生产力发展水平增长较快,但区域差异、经济带差异、城市差异明显;要素生产力保持较高水平,数字生产力和创新生产力加快发展,绿色生产力和产业生产力成为发展的短板。其中,从区域格局来看,东部高于30个省份的平均水平,中西部和东北地区低于30个省份的平均水平;从经济格局来看,长江经济带最高,其次是泛珠三角,而丝绸之路经济带低于30个省份的平均水平;从城市格局来看,三大城市群从高到低依次为珠三角、长三角、京津冀,并且均高于30个省份的平均水平。 展开更多
关键词 新质生产力 生产力发展水平 指标体系 发展差异 生产力测度
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Molten steel level stability in continuous casting slab mold under electromagnetic stirring 被引量:1
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作者 WEN Hongquan WU Cunyou ZHOU Yueming 《Baosteel Technical Research》 CAS 2019年第1期25-31,共7页
Fluctuation of molten steel level in continuous casting process is a critical issue. The analytic function for the liquid steel surface stability index( F) of the continuous casting slab mold under the action of elect... Fluctuation of molten steel level in continuous casting process is a critical issue. The analytic function for the liquid steel surface stability index( F) of the continuous casting slab mold under the action of electromagnetic stirring was derived. The effects on the F value of the electromagnetic field,casting mold,submerged entry nozzle,and casting speed were observed,and the stability of the process parameters of a practical continuous casting system was evaluated. The main results generated are as follows:①Based on the free flow jet theory,a formula is established for the level stability index of continuous casting slab mold under electromagnetic stirring.②According to the results of calculation,the various parameters in decreasing order of the magnitude of their influence are magnetic flux density,nozzle submersion depth,casting speed,slab width,stirring current frequency,and nozzle side-hole inclination angle.③For practical continuous casting with a slab thickness of 230 mm,the calculated F values are between 3 and 5 for different matches between slab width and casting speed,but the parameter optimization space is much larger for wider slab widths and lower casting speeds. 展开更多
关键词 level STABILITY free flow jet electromagnetic STIRRING F -index continuous casting mold
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中国沿海地区热带气旋危险性分析
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作者 张昆 黄全义 栗健 《地理空间信息》 2024年第2期92-96,共5页
基于1980—2016年的西北太平洋热带气旋尺度资料,采用2种方法分析了热带气旋灾害的危险性。第一种方法根据热带气旋的风圈半径,用GIS生成了每个气旋的影响范围,对于登陆中国沿海的227个热带气旋,用叠加法得到了其影响范围与频次。第二... 基于1980—2016年的西北太平洋热带气旋尺度资料,采用2种方法分析了热带气旋灾害的危险性。第一种方法根据热带气旋的风圈半径,用GIS生成了每个气旋的影响范围,对于登陆中国沿海的227个热带气旋,用叠加法得到了其影响范围与频次。第二种方法侧重热带气旋引发的风暴潮灾害,用潮位模型估算了热带气旋登陆时的潮位数据,提出了H3指标,该指标用潮位、风速和中心气压3个因子计算潮位点的风暴潮危险性,并根据H3指标得到了海岸线的危险性综合指标。分析结果表明,福建、广东两省受热带气旋的影响最为严重。37 a间,福建省有80%的面积(约9.8万km^(2))受热带气旋影响的频次超过20次;广东省则有70%的面积(约12.6万km2)受热带气旋影响的频次超过20次。受风暴潮危害大的海岸线主要位于广东、广西、福建、浙江四省,危险性指标在30以上的有广东的湛江市、茂名市、江门市、阳江市和珠海市;广西的北海市、防城港市和钦州市;福建的福州市以及浙江的台州市和温州市。 展开更多
关键词 热带气旋 风圈半径 风暴潮 潮位 危险性指标
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A Multilevel Secure Relation-Hierarchical Data Model for a Secure DBMS
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作者 朱虹 冯玉才 《Journal of Modern Transportation》 2001年第1期8-16,共9页
A multilevel secure relation hierarchical data model for multilevel secure database is extended from the relation hierarchical data model in single level environment in this paper. Based on the model, an upper lowe... A multilevel secure relation hierarchical data model for multilevel secure database is extended from the relation hierarchical data model in single level environment in this paper. Based on the model, an upper lower layer relationalintegrity is presented after we analyze and eliminate the covert channels caused by the database integrity.Two SQL statements are extended to process polyinstantiation in the multilevel secure environment.The system based on the multilevel secure relation hierarchical data model is capable of integratively storing and manipulating complicated objects ( e.g. , multilevel spatial data) and conventional data ( e.g. , integer, real number and character string) in multilevel secure database. 展开更多
关键词 DATABASES data structure data models secure DBMS covert channels mandatory access control POLYINSTANTIATION hierarchical classification non hierarchical category security level integrity cluster index
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气候风险对发展中国家外债水平的影响
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作者 刘志洋 丁洋 张静 《中央财经大学学报》 CSSCI 北大核心 2024年第8期44-56,共13页
外债水平影响国家金融体系稳定,尤其对于发展中国家,然而有关气候风险如何影响发展中国家外债水平的研究文献相对较少。本文使用德国Germanwatch开发的全球气候风险指数,以2007年至2019年全球主要发展中国家为样本,研究气候风险对发展... 外债水平影响国家金融体系稳定,尤其对于发展中国家,然而有关气候风险如何影响发展中国家外债水平的研究文献相对较少。本文使用德国Germanwatch开发的全球气候风险指数,以2007年至2019年全球主要发展中国家为样本,研究气候风险对发展中国家外债水平的影响和作用机制。实证结论表明,第一,气候风险将导致发展中国家公共外债和公共担保私人外债存量、发展中国家长期外债存量显著增加;第二,分位数回归结果显示,极端的气候风险会使发展中国家外债水平显著增加;第三,基于发展中国家样本的调节效应模型显示,整体宏观制度环境好的发展中国家在应对气候风险时外债水平较低;第四,中介效应模型表明,气候风险会导致发展中国家政府财政支出增加,进而引起本国外债的上升。 展开更多
关键词 气候风险 全球气候风险指数 国家外债水平 宏观经济政策 财政支出
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社会体育服务进学校的治理协同度评价指标体系构建研究
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作者 宋宝婵 胡美艳 《体育科技文献通报》 2024年第5期146-149,121,共5页
社会体育服务进学校是未来学校体育发展的重要方向,协同治理理念能够有效应对社会体育服务进学校过程中的治理难题。为科学评估社会体育服务进学校的协同治理,本文以SFIC模型为依据,采用文献资料法、问卷调查法、数理统计法等研究方法,... 社会体育服务进学校是未来学校体育发展的重要方向,协同治理理念能够有效应对社会体育服务进学校过程中的治理难题。为科学评估社会体育服务进学校的协同治理,本文以SFIC模型为依据,采用文献资料法、问卷调查法、数理统计法等研究方法,构建了包含治理主体参与度、治理主体共识度、治理主体成就度、治理主体共享度、治理主体信任度与关系持续度等5个维度、14个二级指标、49个三级指标的社会体育服务进学校的治理协同度评价指标体系。 展开更多
关键词 社会体育服务 学校 协同治理 协同度 评价指标
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Diagnostic Reference Levels of Adults CT-Scan Imaging in Cameroon: A Pilot Study of Four Commonest CT-Protocols in Five Radiology Departments 被引量:1
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作者 Boniface Moifo Jean Roger Moulion Tapouh +3 位作者 Mathurin Neossi Guena Thierry Ndzana Ndah Richard Ndi Samba Augustin Simo 《Open Journal of Medical Imaging》 2017年第1期1-8,共8页
CT-scan is the most irradiating tool in diagnostic radiology. For 5% - 10% of diagnostic X-ray procedures, it is responsible for 34% of irradiation according to UNSCEAR. Patients radiation protection must therefore be... CT-scan is the most irradiating tool in diagnostic radiology. For 5% - 10% of diagnostic X-ray procedures, it is responsible for 34% of irradiation according to UNSCEAR. Patients radiation protection must therefore be increased during CT-scan procedures. This requires the rigorous application of optimization principle which imposes to have “diagnostic reference levels”. Objective: The aim of this study was to determine the diagnostic reference levels (DRLs) of the four most frequent CT-scans examinations of adults in Cameroon. Material and Method: It was a cross-sectional pilot study carried out from April to September 2015 in five health facilities using CT-scan in Cameroon. The studied variables were: patients age and sex, type of CT-scan examination (cerebral, chest, abdomino-pelvic, lumbar spine), Used of IV contrast (IV﹣/ IV+), acquisition length, time of tube rotation, voltage (kV), mAs, pitch, thickness of slices, CTDIvol and DLP. For each type of examination, at least 30 patients were included per center, consecutively on the randomly predetermined days. The DRL for each type of examination was defined as the 75th percentile of its PDL and CTDIvol. Results: Of the 696 examinations, 41.2% were cerebral, 26.9% abdomino-pelvic, 17.7% lumbar spine and 14.2% chest. The mean age of patients was 52 ± 15 years [20 - 90 years], 58.9% were 50 years and older. The sex-ratio was 1.26 (55.9% males). The CT machines were 4, 8 and 16 multidetectors. The 75th percentile of DLP or DRLs [standard deviation] was: [1150 ± 278 mGy·cm], [770 ± 477 mGy·cm], [720 ± 170 mGy·cm] and [715 ± 187 mGy·cm] respectively for cerebral, lumbar spine, abdominopelvic and chest CT-scans. Taking in consideration the number of detectors, the 75th percentile of the Dose-Length product decreased with the increase number of detectors for cerebral examinations but was the highest with 16 MDCT for the abdominopelvic, lumbar spine and chest CT-scans. For the chest and lumbar spine examinations, there was a significant increase in patient-dose with the increase in the number of detectors. Conclusion: Our DRLs values lie between the norms of some European countries and those of some African countries. There is remarquable variation in dose for the commonest CT-scans examinations in Cameroon, requiring then an optimization process from these determined DRLs and establishment of national DRLs. Special attention to optimization should be paid when using 16 MDCT. 展开更多
关键词 Optimization DIAGNOSTIC REFERENCE levelS DOSE Length Product CT DOSE index Patient DOSE Radiation Protection Best Practices
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