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基于减排的水污染物新增量计划指标分配思路和方法
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作者 卢瑛莹 周洋毅 +1 位作者 黄文飞 黄苇 《环境污染与防治》 CAS CSCD 北大核心 2014年第1期89-91,共3页
基于中国刚性减排的污染物总量控制制度,在分析总量控制体系基本逻辑关系的基础上,提出以减量定增量的水污染物新增量计划指标分配思路,在强力削减污染物存量的同时,对区域新增建设项目的污染物新增量进行量化和约束性控制,保障减排目... 基于中国刚性减排的污染物总量控制制度,在分析总量控制体系基本逻辑关系的基础上,提出以减量定增量的水污染物新增量计划指标分配思路,在强力削减污染物存量的同时,对区域新增建设项目的污染物新增量进行量化和约束性控制,保障减排目标的实现。 展开更多
关键词 总量控制 减量定增量 新增量计划指标
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锦州市2015年二氧化硫新增量预测
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作者 鞠菲 《中国环境管理干部学院学报》 CAS 2014年第6期55-58,共4页
根据《"十二五"主要污染物总量控制规划编制技术指南》提供的公式,预测社会经济发展主要参数,包括GDP、能源消费总量、煤炭消费量等指标。二氧化硫新增量预测以宏观测算方法为主,并按行业测算方法予以校核。宏观测算分为火电... 根据《"十二五"主要污染物总量控制规划编制技术指南》提供的公式,预测社会经济发展主要参数,包括GDP、能源消费总量、煤炭消费量等指标。二氧化硫新增量预测以宏观测算方法为主,并按行业测算方法予以校核。宏观测算分为火电行业和非电力行业,结果为1.419万t;分行业预测分为石化、建材(水泥)、有色、冶金和其他行业,结果为1.774万t,两者预测偏差为25%,采用分行业预测结果作为2015年二氧化硫新增量预测。 展开更多
关键词 二氧化硫新增量 宏观测算 排污系数法 年均增长率
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多属性变化的增量关联规则更新研究 被引量:2
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作者 曹增明 于书举 贾豪杰 《计算机工程与应用》 CSCD 北大核心 2010年第30期138-141,共4页
在支持度和事务库发生变化时,如何有效地更新关联规则的问题是目前数据挖掘研究的热点。但当事务库中的属性发生变化时,如何高效地更新关联规则的问题一直都没有引起研究人员的重视。ACA+和ACA-算法对单属性增减后的关联规则进行了研究... 在支持度和事务库发生变化时,如何有效地更新关联规则的问题是目前数据挖掘研究的热点。但当事务库中的属性发生变化时,如何高效地更新关联规则的问题一直都没有引起研究人员的重视。ACA+和ACA-算法对单属性增减后的关联规则进行了研究,在此基础上,提出了解决多属性增减的增量关联规则更新算法MACA+和MACA-。通过建立事务-属性矩阵有效地解决了该问题。 展开更多
关键词 多属性 数据挖掘 关联规则 基于多属性变化 增量式关联规则更
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基于两种新型灰色模型的中国人口预测 被引量:25
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作者 门可佩 官琳琳 尹逊震 《经济地理》 CSSCI 北大核心 2007年第6期942-945,共4页
人口系统是一个典型的灰色系统。根据1949—2005年中国人口发展的最新统计资料,提出并建立离散灰色增量模型和新初值灰色增量模型,对未来中国人口发展趋势进行预测研究。结果表明,到2006年底中国人口约达13.1471亿,到2010年将不超过13.... 人口系统是一个典型的灰色系统。根据1949—2005年中国人口发展的最新统计资料,提出并建立离散灰色增量模型和新初值灰色增量模型,对未来中国人口发展趋势进行预测研究。结果表明,到2006年底中国人口约达13.1471亿,到2010年将不超过13.408亿,2020年不超过13.911亿,2030年约为14.26亿,2040年约为14.50亿,到2050年约为14.66亿。 展开更多
关键词 中国人口发展 离散灰色增量模型 初值灰色增量模型 人口预测
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对“全面二孩”政策下我国学前教育发展战略的建议 被引量:64
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作者 庞丽娟 王红蕾 吕武 《北京师范大学学报(社会科学版)》 CSSCI 北大核心 2016年第6期12-21,共10页
自《教育规划纲要》实施以来,我国学前教育事业取得了显著发展,资源迅速扩大,"入园难"初步缓解。然而,由于底子薄、欠账多,学前教育仍然是我国教育体系中的最薄弱环节。随着我国"全面二孩"政策实施,给本仍短板的学... 自《教育规划纲要》实施以来,我国学前教育事业取得了显著发展,资源迅速扩大,"入园难"初步缓解。然而,由于底子薄、欠账多,学前教育仍然是我国教育体系中的最薄弱环节。随着我国"全面二孩"政策实施,给本仍短板的学前教育带来了满足已有需求和新增人口教育需求的双重挑战和叠加压力。为积极适应与支持国家人口新战略,需以改革的精神做好新形势下我国学前教育事业发展目标规划的调整,并创新思维、主动谋划,加快破除体制机制障碍,建立并完善适应新形势的学前教育管理体制、财政投入体制、办园体制、教师队伍建设政策等,抓紧出台《学前教育法》,在有效化解学前教育历史欠账的同时,积极应对新压力,满足新需求。 展开更多
关键词 “全面二孩”政策 教育新增量 人口与教育 教育发展战略 学前教育发展
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中国人口发展预测研究 被引量:12
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作者 门可佩 官琳琳 尹逊震 《统计与决策》 CSSCI 北大核心 2007年第22期6-9,共4页
本文根据1949-2006年中国人口发展的实际,首次提出离散灰色增量模型和新初值灰色增量模型,并据此对未来中国人口进行预测研究。结果表明,到2007年底中国人口约达13.2133亿,到2010年将不超过13.405亿,2020年不超过13.913亿,2030年约为14... 本文根据1949-2006年中国人口发展的实际,首次提出离散灰色增量模型和新初值灰色增量模型,并据此对未来中国人口进行预测研究。结果表明,到2007年底中国人口约达13.2133亿,到2010年将不超过13.405亿,2020年不超过13.913亿,2030年约为14.27亿,2040年约为14.52亿,到2050年约为14.69亿。 展开更多
关键词 中国人口发展 离散灰色增量模型 初值灰色增量模型 人口预测
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济南市“十二五”期间污染减排形势及对策
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作者 杜逢慧 刘晓 孙明虎 《中国环境管理干部学院学报》 CAS 2016年第1期90-93,共4页
分析了"十二五"期间济南市污染物总量减排工作面临的污染物存量大、新增量迅速增长、工作制约因素多等不利形势。数据表明,到2014年,济南市已提前一年完成"十二五"主要污染物削减目标。同时也指出济南市污染减排存... 分析了"十二五"期间济南市污染物总量减排工作面临的污染物存量大、新增量迅速增长、工作制约因素多等不利形势。数据表明,到2014年,济南市已提前一年完成"十二五"主要污染物削减目标。同时也指出济南市污染减排存在着工作不均衡,尤其是农业源减排进展缓慢的问题。因此,从建立工作协调机制、强化保障措施、消化新增量、产业升级改造等方面提出了深入减排工作的对策。 展开更多
关键词 污染减排 存量 新增量 农业源 对策
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A Spatio-temporal Data Model for Road Network in Data Center Based on Incremental Updating in Vehicle Navigation System 被引量:1
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作者 WU Huisheng LIU Zhaoli +1 位作者 ZHANG Shuwen ZUO Xiuling 《Chinese Geographical Science》 SCIE CSCD 2011年第3期346-353,共8页
The technique of incremental updating,which can better guarantee the real-time situation of navigational map,is the developing orientation of navigational road network updating.The data center of vehicle navigation sy... The technique of incremental updating,which can better guarantee the real-time situation of navigational map,is the developing orientation of navigational road network updating.The data center of vehicle navigation system is in charge of storing incremental data,and the spatio-temporal data model for storing incremental data does affect the efficiency of the response of the data center to the requirements of incremental data from the vehicle terminal.According to the analysis on the shortcomings of several typical spatio-temporal data models used in the data center and based on the base map with overlay model,the reverse map with overlay model (RMOM) was put forward for the data center to make rapid response to incremental data request.RMOM supports the data center to store not only the current complete road network data,but also the overlays of incremental data from the time when each road network changed to the current moment.Moreover,the storage mechanism and index structure of the incremental data were designed,and the implementation algorithm of RMOM was developed.Taking navigational road network in Guangzhou City as an example,the simulation test was conducted to validate the efficiency of RMOM.Results show that the navigation database in the data center can response to the requirements of incremental data by only one query with RMOM,and costs less time.Compared with the base map with overlay model,the data center does not need to temporarily overlay incremental data with RMOM,so time-consuming of response is significantly reduced.RMOM greatly improves the efficiency of response and provides strong support for the real-time situation of navigational road network. 展开更多
关键词 spatio-temporal data model reverse map with overlay model road network incremental updating vehicle navigation system data center vehicle terminal
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Event-based incremental updating of spatio-temporal database 被引量:10
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作者 周晓光 陈军 +2 位作者 蒋捷 朱建军 李志林 《Journal of Central South University of Technology》 2004年第2期192-198,共7页
Based on the relationship among the geographic events, spatial changes and the database operations, a new automatic (semi-automatic) incremental updating approach of spatio-temporal database (STDB) named as (event-bas... Based on the relationship among the geographic events, spatial changes and the database operations, a new automatic (semi-automatic) incremental updating approach of spatio-temporal database (STDB) named as (event-based) incremental updating (E-BIU) is proposed in this paper. At first, the relationship among the events, spatial changes and the database operations is analyzed, then a total architecture of E-BIU implementation is designed, which includes an event queue, three managers and two sets of rules, each component is presented in detail. The process of the E-BIU of master STDB is described successively. An example of building’s incremental updating is given to illustrate this approach at the end. The result shows that E-BIU is an efficient automatic updating approach for master STDB. 展开更多
关键词 incremental updating geographic event spatial change database operation MANAGER
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Improved Pattern Tree for Incremental Frequent-Pattern Mining 被引量:1
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作者 周明 王太勇 《Transactions of Tianjin University》 EI CAS 2010年第2期129-134,共6页
By analyzing the existing prefix-tree data structure, an improved pattern tree was introduced for processing new transactions. It firstly stored transactions in a lexicographic order tree and then restructured the tre... By analyzing the existing prefix-tree data structure, an improved pattern tree was introduced for processing new transactions. It firstly stored transactions in a lexicographic order tree and then restructured the tree by sorting each path in a frequency-descending order. While updating the improved pattern tree, there was no need to rescan the entire new database or reconstruct a new tree for incremental updating. A test was performed on synthetic dataset T1014D100K with 100 000 transactions and 870 items. Experimental results show that the smaller the minimum sup- port threshold, the faster the improved pattern tree achieves over CanTree for all datasets. As the minimum support threshold increased from 2% to 3.5%, the runtime decreased from 452.71 s to 186.26 s. Meanwhile, the runtime re- quired by CanTree decreased from 1 367.03 s to 432.19 s. When the database was updated, the execution time of im- proved pattern tree consisted of construction of original improved pattern trees and reconstruction of initial tree. The experiment results showed that the runtime was saved by about 15% compared with that of CanTree. As the number of transactions increased, the runtime of improved pattern tree was about 25% shorter than that of FP-tree. The improved pattern tree also required less memory than CanTree. 展开更多
关键词 data mining association rules improved pattern tree incremental mining
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Research for a Clean and Large Throughput Differential Pumping System 被引量:1
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作者 蒙峻 杨晓天 +1 位作者 张素平 储继国 《Chinese Physics C》 SCIE CAS CSCD 北大核心 2008年第z1期59-61,共3页
The research is to design a differential pumping system not only to achieve the pressure transition with a large throughput,but also to achieve a clean system without back-oil.In the paper,the pressure in differential... The research is to design a differential pumping system not only to achieve the pressure transition with a large throughput,but also to achieve a clean system without back-oil.In the paper,the pressure in differential stages is calculated;the differential pumping system design and equipment choice are introduced;the tests of Molecular/Booster Pump(MBP),a new kind of molecular-drag pump with large throughout and clean vacuum are described and the system experimental result and analysis are presented. 展开更多
关键词 clean and large throughput differential pumping system new kind of Molecular/Booster Pump back-oil residual gas analysis
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Effects of pre-pregnancy body mass index and gestational weight gain on neonatal birth weight 被引量:2
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作者 Meng-kai DU Li-ya GE +4 位作者 Meng-lin ZHOU Jun YING Fan QU Min-yue DONG Dan-qing CHEN 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2017年第3期263-271,共9页
To evaluate the effects of maternal pre-pregnancy body mass index (pre-BMI) and gestational weight gain (GWG) on neonatal birth weight (NBW) in the population of Chinese healthy pregnant women, attempting to gui... To evaluate the effects of maternal pre-pregnancy body mass index (pre-BMI) and gestational weight gain (GWG) on neonatal birth weight (NBW) in the population of Chinese healthy pregnant women, attempting to guide weight control in pregnancy. A retrospective cohort study of 3772 Chinese women was conducted. The population was stratified by maternal pre-BMI categories as underweight (〈18.5 kg/m2), normal weight (18.5-23.9 kg/m2), overweight (24.0-27.9 kg/m2), and obesity (〉28.0 kg/m2). The NBW differences were tested among the four groups, and then deeper associations among maternal pre-BMI, GWG, and NBW were investigated by multivariate analysis. NBW increased significantly with the increase of maternal pre-BMI level (P〈0.05), except overweight to obesity (P〉0.05). The multivariate analysis showed that both pre-BMI and GWG were positively correlated with NBW (P〈0.05). Compared with normal pre-BMI, underweight predicted an increased odds ratio of small-for-gestational-age (SGA) and decreased odds ratio for macrosomia and large-for-gestational-age (LGA), and the results were opposite for overweight. With the increase of GWG, the risk of SGA decreased and the risks of macrosomia and LGA increased. In addition, in different pre-BMI categories, the effects of weight gain in the first trimester on NBW were different (P〈0.05). NBW is positively affected by both maternal pre-BMI and GWG, extreme pre-BMI and GWG are both associated with increased risks of abnormal birth weight, and maternal pre-BMI may modify the effect of weight gain in each trimester on NBW. A valid GWG guideline for Chinese women is an urgent requirement, whereas existing recommendations seem to be not very suitable for the Chinese. 展开更多
关键词 Pre-pregnancy body mass index Gestational weight gain Neonatal birth weight Appropriate weight gain pattern
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