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健全现代预算制度的理论分析与实践思考 被引量:1
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作者 马蔡琛 唐卓越 《财政科学》 2025年第1期72-79,共8页
党的二十届三中全会提出健全预算制度的要求,明确了现代预算制度改革的方向。健全预算制度不仅依赖于制度设计的完善,更需在实践中不断探索创新。建议从资金管理、主体维度增强预算制度的完整性,深化零基预算改革、强化事前功能评估、... 党的二十届三中全会提出健全预算制度的要求,明确了现代预算制度改革的方向。健全预算制度不仅依赖于制度设计的完善,更需在实践中不断探索创新。建议从资金管理、主体维度增强预算制度的完整性,深化零基预算改革、强化事前功能评估、完善跨部门预算绩效考察制度、推动年度预算与中期财政规划衔接以提高预算制度的有效性,建立分类规范的预算信息公开制度和权责发生制政府综合财务报告制度以保证预算制度的透明度,从而在实践中不断健全统筹有力、科学高效、规范透明的现代预算制度。 展开更多
关键词 现代预算制度 财税体制改革 零基预算 中期财政规划
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基于实时预算模型的全过程绩效管理改革
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作者 马蔡琛 白铂 《中央财经大学学报》 北大核心 2025年第7期5-18,共14页
为探究预算过程与环境对预算决策的影响,实时预算模型将预算过程解构为五个决策束,即收入束、过程束、支出束、平衡束和执行束。模型所体现的资源竞争性、环境开放性和过程半独立性特征,对于各级政府预算管理均具有适用价值。实践表明,... 为探究预算过程与环境对预算决策的影响,实时预算模型将预算过程解构为五个决策束,即收入束、过程束、支出束、平衡束和执行束。模型所体现的资源竞争性、环境开放性和过程半独立性特征,对于各级政府预算管理均具有适用价值。实践表明,实时预算模型对传统预算绩效管理提出了更高要求,具体表现为:需要构建更客观的事前绩效评估框架、动态化的实时绩效监控体系以及更有效的评价结果应用机制。面向健全预算制度的时代要求,需要基于各决策束的核心功能,从中期视角下的绩效目标与指标设置、以逻辑模型为基础的事前绩效评估框架、以关键绩效指标为抓手的动态监控机制、跨期视角下的绩效评价结果应用等方面加以谋划,进而实现全过程预算绩效管理闭环。 展开更多
关键词 实时预算模型 预算绩效管理 健全预算制度 财政资源统筹 中期财政框架
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考虑多工况特性的电-氢耦合系统规划方法 被引量:2
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作者 覃惠玲 卢纯颢 +3 位作者 罗阳洋 程敏 温紫豪 任洲洋 《电工电能新技术》 北大核心 2025年第1期69-81,共13页
氢能系统包含多元化的氢能设备且运行特性各异,会对配电网运行和规划产生交互影响。为此,本文提出了一种考虑多工况特性的电-氢耦合系统规划方法。从物理原理出发,研究电解槽、甲烷化设备的多工况转换耗时耗能特性和氢燃料电池的变效率... 氢能系统包含多元化的氢能设备且运行特性各异,会对配电网运行和规划产生交互影响。为此,本文提出了一种考虑多工况特性的电-氢耦合系统规划方法。从物理原理出发,研究电解槽、甲烷化设备的多工况转换耗时耗能特性和氢燃料电池的变效率特性。考虑电解槽和甲烷化设备冷备用、热备用、正常工作三种工况,氢燃料电池的低、高运行功率两种工况,系统性地建立考虑多工况运行特性的氢能设备运行模型。为了验证所提方法的有效性,对基于IEEE 33节点的电网和10节点的气网组成的区域综合能源测试系统进行仿真测试。仿真结果表明,若忽略氢能设备多工况运行特性,会高估氢能设备灵活性,导致其规划容量与实际情况产生较大偏差。 展开更多
关键词 电-氢耦合系统 中长期规划 甲烷化 电解槽 氢燃料电池 多工况
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铁路网规划的发展历程与应用实践 被引量:3
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作者 高明明 《铁道运输与经济》 北大核心 2025年第4期62-67,共6页
铁路网规划体系在我国交通基础设施规划领域占据着关键地位。铁路网规划体系构建上,其多元的分类方式适应了不同层面与对象的规划需求,无论是基于时间维度的中长期与五年规划,还是聚焦于特定研究对象的各类铁路规划,均为铁路规划建设的... 铁路网规划体系在我国交通基础设施规划领域占据着关键地位。铁路网规划体系构建上,其多元的分类方式适应了不同层面与对象的规划需求,无论是基于时间维度的中长期与五年规划,还是聚焦于特定研究对象的各类铁路规划,均为铁路规划建设的有序推进奠定了重要基础。通过研究铁路网规划体系构成,分析路网规划的主要内容、规划方法及规划作用,根据铁路网规划发展情况,回顾中长期铁路网规划的发展过程及对铁路发展起到的作用。在总结铁路网规划发展的前提下,对新形势下铁路网规划发展的趋势进行探讨,提出打造多层次、一体化的轨道网络,并以长三角“四网融合”为例加以阐述,为铁路网规划研究提供参考。 展开更多
关键词 规划体系 中长期铁路网规划 “四网融合” 发展趋势 应用实践
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基于数字孪生与灰色预测算法的电力系统中长期负荷预测研究 被引量:1
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作者 薛涛 张丁月 +3 位作者 程爱勇 傅谦晶 刘广华 王鹏飞 《国外电子测量技术》 2025年第2期128-134,共7页
电力系统负荷具有时变性和不确定性,且历史负荷数据的稀疏性也会导致预测模型因训练不足而产生较大偏差。为此,提出基于数字孪生与灰色预测算法的电力系统中长期负荷预测方法。首先,根据电力系统的负荷类型,通过数字孪生模型,将电力系... 电力系统负荷具有时变性和不确定性,且历史负荷数据的稀疏性也会导致预测模型因训练不足而产生较大偏差。为此,提出基于数字孪生与灰色预测算法的电力系统中长期负荷预测方法。首先,根据电力系统的负荷类型,通过数字孪生模型,将电力系统的物理实体与虚拟模型相结合,实时获取多维数据,弥补历史负荷数据的不足。利用快速傅里叶方法提取负荷的时域和频域瞬态分量,并建立负荷衍生特征。结合数字孪生体中负荷与影响因素间的关系,利用最大信息系数对其进行耦合特性分析,提取强相关性负荷数据。依据强关联性负荷数据的测量协方差矩阵,利用高斯隶属函数提取负荷的尺度特征;然后,利用局部加权方法对负荷数据的多维时域特征进行时间序列分解,得到周期分量、趋势分量以及残差分量;最后,引入灰色系统理论构建负荷预测模型,实现对电力系统中长期负荷的预测。灰色系统理论适用于小样本数据,能够在中长期负荷数据稀疏的情况下有效处理负荷数据中的不确定性和随机性,提高预测精度。实验结果表明,应用该方法得到的预测结果与实际结果的相关指数高于0.8,负荷波动捕捉率保持始终低于1%,预测结果保留率保持在93.3%~95.6%之间,说明该方法具有较高的预测精度。 展开更多
关键词 数字孪生 灰色预测 电力系统 中长期负荷 预测模型
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基于岗位价值的岗位分红企业薪酬管理创新实践——以Z公司为例
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作者 谭翔 王宇成 《市场周刊》 2025年第27期175-178,共4页
现代企业之间的竞争聚焦在人才,薪酬作为吸引人才的重要手段,薪酬管理创新是企业发展的关键因素。为解决“不愿转”“不敢转”等普遍存在的痛点以及长期牵引目标机制不足的风险,Z公司在国家相关政策的指引下,运用岗位价值评估模型开展... 现代企业之间的竞争聚焦在人才,薪酬作为吸引人才的重要手段,薪酬管理创新是企业发展的关键因素。为解决“不愿转”“不敢转”等普遍存在的痛点以及长期牵引目标机制不足的风险,Z公司在国家相关政策的指引下,运用岗位价值评估模型开展岗位分红机制,以六要素价值创造筛选模型选取激励对象,按照“两级考核”及价值贡献系数进行兑现,“因企制宜”开展薪酬管理创新,最大限度激发员工活力。 展开更多
关键词 岗位分红 薪酬管理 中长期激励
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Studies on hybridization effects of different geographic populations of Chlamys farreri Ⅱ.The medium-term growth and development of Chlamys farreri populations from China and Russia and their reciprocal crosses 被引量:12
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作者 LiuXiaolin ChangYaqing +3 位作者 XiangJianhai LiFuhua LiuXianjie BrovkinaElenaPavlovna 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2003年第2期255-264,共10页
Based on the research of juvenile (2, 3, 4 months) growth and survival of three populations of two different geographic areas in Chlamys farreri from Russian and China and their F1 hybrids derived from Chinese cultura... Based on the research of juvenile (2, 3, 4 months) growth and survival of three populations of two different geographic areas in Chlamys farreri from Russian and China and their F1 hybrids derived from Chinese cultural population (CC) (?) × Russian population (RW) (?) , Chinese wild population (CW) (?) × Russian population (RW) (?), Russian population (RW) (?) × Chinese wild population (CW) (?) , the study of the medium-term (6, 8, 10, 12 months) growth and development of Chlamys farreri was carried out. The four determined results indicated that there existed different extent heterosis (3% -52%) for the growth in three types of F1 hybrids, and the offspring derived from CC(?) ×R(?) had a stronger heterosis among the crosses at the medium-term; the uptrend among traits are wet weight >shell width>shell length> shell height, Chinese cultural population could be recognized as excellent parent, and seasonal variations influence very much on the daily increment and growth rate of each trait of Chlamys farreri and it is only able to survive and could barely grow in winter (6-8 months), but grows fast in temperate season (10-12 months). 展开更多
关键词 Chlamys farreri POPULATION HYBRIDIZATION medium-term growth and development HETEROSIS
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Medium-term surgical outcomes and health-related quality of life after laparoscopic vs open colorectal cancer resection: SF-36 health survey questionnaire 被引量:10
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作者 Chao-Ming Hung Kuo-Chuan Hung +11 位作者 Hon-Yi Shi Shih-Bin Su Hui-Ming Lee Meng-Che Hsieh Cheng-Hao Tseng Shung-Eing Lin Chih-Cheng Chen Chao-Ming Tseng Ying-Nan Tsai Chi-Zen Chen Jung-Fa Tsai Chong-Chi Chiu 《World Journal of Gastrointestinal Endoscopy》 2023年第3期163-176,共14页
BACKGROUND Previous studies that compared the postoperative health-related quality of life(HRQoL)outcomes after receiving laparoscopic resection(LR)or open resection(OR)in patients with colorectal cancer(CRC)have diff... BACKGROUND Previous studies that compared the postoperative health-related quality of life(HRQoL)outcomes after receiving laparoscopic resection(LR)or open resection(OR)in patients with colorectal cancer(CRC)have different conclusions.AIM To explore the medium-term effect of postoperative HRQoL in such patients.METHODS This study randomized 567 patients undergoing non-metastatic CRC surgery managed by one surgeon to the LR or OR groups.HRQoL was assessed during the preoperative period and 3,6,and 12 mo postoperative using a modified version of the 36-Item Short Form(SF-36)Health Survey questionnaire,emphasizing eight specific items.RESULTS This cohort randomly assigned 541 patients to receive LR(n=296)or OR(n=245)surgical procedures.More episodes of postoperative urinary tract infection(P<0.001),wound infection(P<0.001),and pneumonia(P=0.048)were encountered in the OR group.The results demonstrated that the LR group subjectively gained mildly better general health(P=0.045),moderately better physical activity(P=0.006),and significantly better social function recovery(P=0.0001)3 mo postoperatively.Only the aspect of social function recovery was claimed at 6 mo,with a significant advantage in the LR group(P=0.001).No clinical difference was found in HRQoL during the 12 mo.CONCLUSION Our results demonstrated that LR resulted in better outcomes,including intra-operative blood loss,surgery-related complications,course of recovery,and especially some health domains of HRQoL at least within 6 mo postoperatively.Patients should undergo LR if there is no contraindication. 展开更多
关键词 Health-related quality of life medium-term result LAPAROSCOPIC Open surgery Non-metastatic colorectal cancer
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中长期市场下多能互补系统经济性研究
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作者 陈业帅 卞国良 《电器与能效管理技术》 2025年第7期59-70,80,共13页
在“双碳”目标驱动下,可再生能源规模化发展面临间歇性与波动性带来的消纳挑战。为提升系统灵活性,促进可再生能源消纳,基于国家“源网荷储一体化与多能互补”政策导向,研究多能互补系统在电力市场中互补模式的经济性与稳定性优势。通... 在“双碳”目标驱动下,可再生能源规模化发展面临间歇性与波动性带来的消纳挑战。为提升系统灵活性,促进可再生能源消纳,基于国家“源网荷储一体化与多能互补”政策导向,研究多能互补系统在电力市场中互补模式的经济性与稳定性优势。通过综合考虑电力市场细则与多能互补特性,构建了中长期市场出清模型,并基于非线性规划理论和粒子群优化算法,模拟求解发电企业报价策略与大用户购电决策。通过市场出清结果分析与政策适应性研究,验证了多能互补系统在经济效益、市场韧性、成本结构等方面的优势,为市场化消纳可再生能源提供了理论支持。 展开更多
关键词 中长期市场 多能互补系统 可再生能源消纳 电力系统灵活性
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“十四五”水电发展现状和中长期展望
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作者 韩冬 崔正辉 +1 位作者 周力 萧子钧 《水利水电快报》 2025年第10期46-53,共8页
中国水力资源丰富,经过多年发展,水电勘测设计、工程建设、装备制造等全产业链达到世界领先水平。“十四五”时期是中国水电由高速发展向高质量发展的关键阶段,在“双碳”战略引领下,水电功能定位发生转变,水电建设规模持续跃升发展,水... 中国水力资源丰富,经过多年发展,水电勘测设计、工程建设、装备制造等全产业链达到世界领先水平。“十四五”时期是中国水电由高速发展向高质量发展的关键阶段,在“双碳”战略引领下,水电功能定位发生转变,水电建设规模持续跃升发展,水电发展模式实现创新拓展。通过系统梳理分析水电发展情况,重点对“十四五”以来水电规划目标、重大任务等情况进行回顾,结合当前新型能源体系、新型电力系统建设的新形势新要求,分析水电面临的机遇挑战,并对未来水电发展思路、功能定位等进行展望。结果表明:“十四五”以来,中国水电新增投产整体符合进度要求、新增核准装机规模已完成规划目标;“十五五”及中长期,水电发展思路为“增量发展与存量提升”并重,功能定位为“电量供应与容量支撑”并重,预计到2050年中国常规水电装机规模有望达5亿kW以上。研究成果可为中国水电行业可持续发展提供重要的数据支撑与策略参考。 展开更多
关键词 常规水电 新型电力系统 发展现状 中长期发展展望
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ANALYSES OF ERRORS IN MEDIUM-TERM NUMERICAL FORECAST PRODUCTS FOR THE SUBTROPICAL HIGH 1998 被引量:1
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作者 王兴荣 姚叶青 +3 位作者 尚瑜 陈晓平 程小泉 率爱梅 《Journal of Tropical Meteorology》 SCIE 2003年第1期105-112,共8页
By statistic and dynamic analyses, we have come to the following conclusions: (1) The ECMWF medium-term numerical forecast can forecast medium-term activity of subtropical high, and the accuracy rate of forecast canno... By statistic and dynamic analyses, we have come to the following conclusions: (1) The ECMWF medium-term numerical forecast can forecast medium-term activity of subtropical high, and the accuracy rate of forecast cannot have large improvement by translational corrections. (2) The important cause for the ECMWF medium-term numerical forecast to have errors in 1998 is that the astronomical tide is not included in the model. (3) Two indexes are found from which it can be judged that ECMWF medium-term numerical forecast will have errors if the astronomical tide is ignored in the model : ① When the 54.7?line under the moon of the nodical month astronomical singularities coincides with the trough-line of the subtropical jet flow from 50癊 to 150癊 on the 500 hPa level at 2000 L.T. of the same day, and is approximately vertical (α>60? with the isotherm, then the day 0 2 days after the appearance of the nodical month astronomical singularities is defined as the initial day. Then in three successive days after the initial day, ECMWF medium-term numerical forecast of the northern latitude of the 588 line at 120 癊 will have continuous errors as large as two latitudes (7/9). Otherwise, it won’t have continuous errors (13/13). ② Otherwise, if the 54.7 ?line is in the range of a low pressure between two high pressures, then there is a dispersive error on the day of the nodical month astronomical singularities (5/7). There is not any error (6/6) otherwise. 展开更多
关键词 ECMWF medium-term numerical forecast subtropical high error analysis astronomical tide analysis of dynamics
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基于MGM(1,n,λ)与多任务学习的中长期逐时负荷预测
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作者 王育飞 顾嘉睿 郝德扬 《上海电力大学学报》 2025年第3期208-215,共8页
为解决中长期多元负荷预测时间分辨率过低、精度有限等问题,对多元负荷的长期变化趋势和短期动态特征分别进行建模分析,提出了基于多变量灰色模型(MGM)与多任务学习的中长期逐时负荷预测方法。首先,利用Copula理论对多元负荷进行相关性... 为解决中长期多元负荷预测时间分辨率过低、精度有限等问题,对多元负荷的长期变化趋势和短期动态特征分别进行建模分析,提出了基于多变量灰色模型(MGM)与多任务学习的中长期逐时负荷预测方法。首先,利用Copula理论对多元负荷进行相关性分析,并建立了基于MGM(1,n,λ)的长期趋势预测模型;然后,为充分挖掘和利用负荷间耦合特征,将原始的多元负荷数据重构成三维融合特征,作为特征共享层输入特征;最后,建立了基于残差网络的多任务逐时负荷预测模型,并输出多元负荷预测值。算例分析结果表明,所提方法具有较高的预测精度和计算效率。 展开更多
关键词 多变量灰色模型 多任务学习 中长期负荷预测 综合能源系统 残差网络
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The Relationship Between Abnormal Meiyu and Medium-Term Scale Wave Perturbation Energy Propagation Along the East Asian Subtropical Westerly Jet 被引量:1
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作者 JIN Rong-hua YANG Ning +2 位作者 SUN Xiao-qing LIU Si-jia YIN Shan 《Journal of Tropical Meteorology》 SCIE 2020年第2期125-136,共12页
The East Asian subtropical westerly jet(EASWJ)is one of the most important factors modulating the Meiyu rainfall in the Yangtze-Huaihe River Basin,China.This article analyzed periods of the medium-term EASWJ variation... The East Asian subtropical westerly jet(EASWJ)is one of the most important factors modulating the Meiyu rainfall in the Yangtze-Huaihe River Basin,China.This article analyzed periods of the medium-term EASWJ variation,wave packet distribution and energy propagation of Rossby waves along the EASWJ during Meiyu season,and investigated their possible influence on abnormal Meiyu rain.The results showed that during the medium-term scale atmospheric dynamic process,the evolution of the EASWJ in Meiyu season was mainly characterized by the changes of3-8 d synoptic-scale and 10-15 d low-frequency Rossby waves.The strong perturbation wave packet and energy propagation of the 3-8 d synoptic-scale and 10-15 d low-frequency Rossby waves are mostly concentrated in the East Asian region of 90°-150°E,where the two wave trains of perturbation wave packets and wave-activity flux divergence coexist in zonal and meridional directions,and converge on the EASWJ.Besides,the wave trains of perturbation wave packet and wave-activity flux divergence in wet Meiyu years are more systematically westward than those in dry Meiyu years,and they are shown in the inverse phases between each other.In wet(dry)Meiyu year,the perturbation wave packet high-value area of the 10-15 d low-frequency variability is located between the Aral Sea and the Lake Balkhash(in the northeastern part of China),while over eastern China the wave-activity flux is convergent and strong(divergent and weak),and the high-level jets are strong and southward(weak and northward).Because of the coupling of high and low level atmosphere and high-level strong(weak)divergence on the south side of the jet over the Yangtze-Huaihe River Basin,the low-level southwest wind and vertically ascending motion are strengthened(weakened),which is(is not)conducive to precipitation increase in the Yangtze-Huaihe River Basin.These findings would help to better understand the impact mechanisms of the EASWJ activities on abnormal Meiyu from the perspective of medium-term scale Rossby wave energy propagation. 展开更多
关键词 East Asian subtropical westerly jet(EASWJ) medium-term scale Rossby wave wave packet distribution energy propagation abnormal Meiyu
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Medium-Term Electric Load Forecasting Using Multivariable Linear and Non-Linear Regression 被引量:2
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作者 Nazih Abu-Shikhah Fawwaz Elkarmi Osama M. Aloquili 《Smart Grid and Renewable Energy》 2011年第2期126-135,共10页
Medium-term forecasting is an important category of electric load forecasting that covers a time span of up to one year ahead. It suits outage and maintenance planning, as well as load switching operation. We propose ... Medium-term forecasting is an important category of electric load forecasting that covers a time span of up to one year ahead. It suits outage and maintenance planning, as well as load switching operation. We propose a new methodol-ogy that uses hourly daily loads to predict the next year hourly loads, and hence predict the peak loads expected to be reached in the next coming year. The technique is based on implementing multivariable regression on previous year's hourly loads. Three regression models are investigated in this research: the linear, the polynomial, and the exponential power. The proposed models are applied to real loads of the Jordanian power system. Results obtained using the pro-posed methods showed that their performance is close and they outperform results obtained using the widely used ex-ponential regression technique. Moreover, peak load prediction has about 90% accuracy using the proposed method-ology. The methods are generic and simple and can be implemented to hourly loads of any power system. No extra in-formation other than the hourly loads is required. 展开更多
关键词 medium-term LOAD Forecasting Electrical PEAK LOAD MULTIVARIABLE Regression And TIME SERIES
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Medium-term and Long-term Momentum and Contrarian Effects on China during 1994-2004 被引量:1
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作者 DU Xing-qiang NIE Zhi-ping 《Journal of Modern Accounting and Auditing》 2007年第2期63-69,共7页
We examine momentum and contrarian effects in China's stock market during 1994-2004 and find that no medium momentum effects exist. Meanwhile, contrarian strategy works effectively over the horizon of 18-36 months. 1... We examine momentum and contrarian effects in China's stock market during 1994-2004 and find that no medium momentum effects exist. Meanwhile, contrarian strategy works effectively over the horizon of 18-36 months. 1-month gap for avoiding bid-ask bounce and lead-lag effect make no considerable change to our empirical results. Transaction costs seem to have no significant impact on contrarian strategies' profit. 展开更多
关键词 medium-term momentum long-term momentum contrafian effects transaction costs
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Medium-term forecast of daily passenger volume of high speed railway based on DLP-WNNMedium-term forecast of dailypassenger volume of high speedrailway based on DLP-WNN 被引量:1
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作者 Tangjian Wei Xingqi Yang +1 位作者 Guangming Xu Feng Shi 《Railway Sciences》 2023年第1期121-139,共19页
Purpose – This paper aims to propose a medium-term forecast model for the daily passenger volume of HighSpeed Railway (HSR) systems to predict the daily the Origin-Destination (OD) daily volume formultiple consecutiv... Purpose – This paper aims to propose a medium-term forecast model for the daily passenger volume of HighSpeed Railway (HSR) systems to predict the daily the Origin-Destination (OD) daily volume formultiple consecutivedays (e.g. 120 days).Design/methodology/approach – By analyzing the characteristics of the historical data on daily passengervolume of HSR systems, the date and holiday labels were designed with determined value ranges.In accordance to the autoregressive characteristics of the daily passenger volume of HSR, the Double LayerParallel Wavelet Neural Network (DLP-WNN) model suitable for the medium-term (about 120 d) forecast of thedaily passenger volume of HSR was established. The DLP-WNN model obtains the daily forecast result byweighed summation of the daily output values of the two subnets. Subnet 1 reflects the overall trend of dailypassenger volumes in the recent period, and subnet 2 the daily fluctuation of the daily passenger volume toensure the accuracy of medium-term forecast.Findings – According to the example application, in which the DLP-WNN modelwas used for the medium-termforecast of the daily passenger volumes for 120 days for typical O-D pairs at 4 different distances, the averageabsolute percentage error is 7%-12%, obviously lower than the results measured by the Back Propagation (BP)neural network, the ELM (extreme learning machine), the ELMAN neural network, the GRNN (generalizedregression neural network) and the VMD-GA-BP. The DLP-WNN model was verified to be suitable for themedium-term forecast of the daily passenger volume of HSR.Originality/value – This study proposed a Double Layer Parallel structure forecast model for medium-termdaily passenger volume (about 120 days) of HSR systems by using the date and holiday labels and WaveletNeural Network. The predict results are important input data for supporting the line planning, scheduling andother decisions in operation and management in HSR systems. 展开更多
关键词 High speed railway Passenger flow forecast Daily passenger volume medium-term forecast Wavelet neural network
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Refrigeration Calculation and System Design for Medium-term Genebank of Crop Germplasm Resources in Shandong Province
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作者 李湛 张晓冬 +4 位作者 李润芳 王栋 刘世华 李娜娜 丁汉凤 《Agricultural Science & Technology》 CAS 2016年第8期1929-1932,共4页
Crop germplasm resources are the material basis for the breeding of new varieties, and strategic resources for food production, ecological security and agricultural sustainable development. Constructing a scientific, ... Crop germplasm resources are the material basis for the breeding of new varieties, and strategic resources for food production, ecological security and agricultural sustainable development. Constructing a scientific, environmental-friendly and energy-saving medium-term genebank is essential for preserving crop germplasm resources. However, the construction of medium-term genebank involves a wide range of subjects but lacks unified standard, which might result in many difficulties in the process of construction and application. According to the key parameters of refrigeration system for medium-term genebank, the cooling load was calculated and key system schemes were determined in this paper. Based on the calculation results and designed schemes, the equipment selection was discussed and the standards for construction of bank and monitoring system were proposed with the aim to provide references for germplasm genebank design and equipment selection. 展开更多
关键词 CROP Germplasm resource medium-term genebank Cooling load Equipment selection Shandong Province
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Seismicity Quantification and Its Application to Medium-term Earthquake Prediction
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作者 Wang Wei , Liu Zheng , Song Xianyue and Wang ZhengzhengSeismological Bureau of Shanghai Municipality, Shanghai 200062, China Seismological Bureau of Jiangsu Province, Nanjing 210014, China 《Earthquake Research in China》 2000年第1期30-41,共12页
Bed on the analysis of each parameter describing seismicity,we think A(b)-value can betterquantitatively describe the feature of the enhancement and quietness of seismicity in this paper. Thedata of moderate or small ... Bed on the analysis of each parameter describing seismicity,we think A(b)-value can betterquantitatively describe the feature of the enhancement and quietness of seismicity in this paper. Thedata of moderate or small earthquakes during 1972~1996 in North China are used in space scanningof A(b)-value. The result shows that 2~3 years before most strong earthquakes there wereObviously anomaly zones of A(b)-value with very good prediction effect. Some problems about themedium-term prediction by using A(b)-value are also discussed. 展开更多
关键词 ENHANCEMENT and QUIETNESS of SEISMICITY A (b)-value medium-term EARTHQUAKE prediction
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Determination of Regions With Medium-Term Risk of Strong Earthquakes: Pre-warning Active Faults
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作者 Ge Shumo and Wei RuopingSeismological Bureau of Xinjiang Uygur Autonomous Region,Urumqi 830011,China 《Earthquake Research in China》 1996年第1期104-109,共6页
To predict the area with frequent seismicity and the future risky region of strong earthquakes on the time scale of one or several years is a very important and urgent problem that needs to be solved.On the basis of a... To predict the area with frequent seismicity and the future risky region of strong earthquakes on the time scale of one or several years is a very important and urgent problem that needs to be solved.On the basis of active fault research,pre-warning active faults that have been active recently will be discussed; then the medium-term risky region of strong earthquakes will be delimited around the pre-warning active faults.This method proves to be effective. 展开更多
关键词 SEISMIC RISK REGION medium-term prediction ACTIVE FAULT
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Medium-term Air Quality Benchmarking for Ecosystem Monitoring and Sustainability Planning: Case Study Dallas County (U.S.A.) 2015 to 2020
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作者 David A.Wood 《Research in Ecology》 2021年第4期35-53,共19页
Medium-term air quality assessment,benchmarking it to recent past data can usefully complement short-term air quality index data for monitoring purposes.By using daily and monthly averaged data,medium-term air quality... Medium-term air quality assessment,benchmarking it to recent past data can usefully complement short-term air quality index data for monitoring purposes.By using daily and monthly averaged data,medium-term air quality benchmarking provides a distinctive perspective with which to monitor air quality for sustainability planning and ecosystem perspectives.By normalizing the data for individual air pollutants to a standard scale they can be more easily integrated to generate a daily combined local area benchmark(CLAB).The objectives of the study are to demonstrate that medium-term air quality benchmarking can be tailored to reflect local conditions by selecting the most relevant pollutants to incorporate in the CLAB indicator.Such a benchmark can provide an overall air quality assessment for areas of interest.A case study is presented for Dallas County(U.S.A.)applying the proposed method by benchmarking 2020 data for air pollutants to their trends established for 2015 to 2019.Six air pollutants considered are:ozone,carbon monoxide,nitrogen dioxide,sulfur dioxide,benzene and particulate matter less than 2.5 micrometres.These pollutants are assessed individually and in terms of CLAB,and their 2020 variations for Dallas County compared to daily trends established for years 2015 to 2019.Reductions in benzene and carbon monoxide during much of 2020 are clearly discernible compared to preceding years.The CLAB indicator shows clear seasonal trends for air quality for 2015 to 2019 with high pollution in winter and spring compared to other seasons that is strongly influenced by climatic variations with some anthropogenic inputs.Conducting CLAB analysis on an ongoing basis,using a relevant near-past time interval for benchmarking that covers several years,can reveal useful monthly,seasonal and annual trends in overall air quality.This type of medium-term,benchmarked air quality data analysis is well suited for ecosystem monitoring. 展开更多
关键词 Local air pollution assessment medium-term air quality Local area benchmarking Critical pollutants Seasonal variations in air quality Sustainability planning
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