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平行机的实时到达on-line算法下界的改进 被引量:1
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作者 陈仕平 姚恩瑜 《高校应用数学学报(A辑)》 CSCD 北大核心 1999年第3期315-318,共4页
本文考虑了平行机实时到达的在线问题.模型中,工件是陆续到达的,工件的个数、到达时间是事先未知的,而且只有当工件到达,才知其加工时间,目标是使所有工件都加工完的时间达到最小.Chen与Vestjens(1996年)证明... 本文考虑了平行机实时到达的在线问题.模型中,工件是陆续到达的,工件的个数、到达时间是事先未知的,而且只有当工件到达,才知其加工时间,目标是使所有工件都加工完的时间达到最小.Chen与Vestjens(1996年)证明了该在线问题不存在性能比小于1.3473的on-line算法.本文将此界改进为(5-5)/2. 展开更多
关键词 排序 on-line算法 平行机 组合最优化 实时到达
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On-line置换液与生理盐水在血液透析滤过回血中的应用效果比较 被引量:5
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作者 祝喜鹰 刘金凤 肖静 《护理研究(上旬版)》 2014年第7期2370-2372,共3页
[目的]探讨On-line置换液与生理盐水在血液透析滤过(HDF)病人回血中的应用效果,以期为临床护理工作提供理论依据。[方法]选取30例规律HDF病人为研究对象,采用自身对照方法,每例病人每周依次采用On-line置换液和生理盐水回血,比较回血过... [目的]探讨On-line置换液与生理盐水在血液透析滤过(HDF)病人回血中的应用效果,以期为临床护理工作提供理论依据。[方法]选取30例规律HDF病人为研究对象,采用自身对照方法,每例病人每周依次采用On-line置换液和生理盐水回血,比较回血过程中残余血量、静脉壶液体温度、护士的工作量及经济效益。[结果]采用On-line置换液回血法残余血量及回血后静脉壶温度分别为(1.89±0.91)mL,(33.36±0.15)℃,而采用生理盐水法为(2.88±0.23)mL、(27.13±0.14)℃,差异均有统计学意义(P<0.01);而透析器凝血状况比较差异无统计学意义(P=0.08);采用On-line置换液回血时护士工作量减少,回血液体成本降低。[结论]应用接近生理温度的On-line置换液回血能稀释血液、降低血液黏稠度,减少血路管残余血量,增加病人舒适感,提高工作效率。 展开更多
关键词 联机血液透析滤过 液体回血 on-line置换液 生理盐水 残余血量 工作量
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Self-adaptive PID controller of microwave drying rotary device tuning on-line by genetic algorithms 被引量:6
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作者 杨彪 梁贵安 +5 位作者 彭金辉 郭胜惠 李玮 张世敏 李英伟 白松 《Journal of Central South University》 SCIE EI CAS 2013年第10期2685-2692,共8页
The control design, based on self-adaptive PID with genetic algorithms(GA) tuning on-line was investigated, for the temperature control of industrial microwave drying rotary device with the multi-layer(IMDRDWM) and wi... The control design, based on self-adaptive PID with genetic algorithms(GA) tuning on-line was investigated, for the temperature control of industrial microwave drying rotary device with the multi-layer(IMDRDWM) and with multivariable nonlinear interaction of microwave and materials. The conventional PID control strategy incorporated with optimization GA was put forward to maintain the optimum drying temperature in order to keep the moisture content below 1%, whose adaptation ability included the cost function of optimization GA according to the output change. Simulations on five different industrial process models and practical temperature process control system for selenium-enriched slag drying intensively by using IMDRDWM were carried out systematically, indicating the reliability and effectiveness of control design. The parameters of proposed control design are all on-line implemented without iterative predictive calculations, and the closed-loop system stability is guaranteed, which makes the developed scheme simpler in its synthesis and application, providing the practical guidelines for the control implementation and the parameter design. 展开更多
关键词 industrial microwave DRYING ROTARY device SELF-ADAPTIVE PID controller genetic algorithm on-line tuning SELENIUM-ENRICHED SLAG
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Reagent optimization for on-line simultaneous polarographic determination of trace amounts of Cu^(2+), Cd^(2+) and Co^(2+) in the presence of anextremely large excess of Zn^(2+) 被引量:4
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作者 WANG Guo-wei YANG Chun-hua +2 位作者 ZHU Hong-qiu LI Yong-gang GUI Wei-hua 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第9期2199-2204,共6页
Reagents are optimized for the simultaneous determination of trace amounts of Cu^(2+), Cd^(2+) and Co^(2+) in zinc sulfate solution, which contains an extremely large excess of Zn^(2+). First, the reagents and their d... Reagents are optimized for the simultaneous determination of trace amounts of Cu^(2+), Cd^(2+) and Co^(2+) in zinc sulfate solution, which contains an extremely large excess of Zn^(2+). First, the reagents and their doses for the experiment are selected according to the characteristics of the zinc sulfate solution. Then, the reagent doses are optimized by analyzing the influence of reagent dose on the polarographic parameters(i.e. half-wave potential E_(1/2) and limiting diffusion current I_p). Finally, the optimization results are verified by simultaneously determining trace amounts of Cu^(2+), Cd^(2+) and Co^(2+) in the presence of an extremely large excess of Zn^(2+). The determination results indicate that the optimized reagents exhibit wide linearity, low detection limits, high accuracy and good precision for the simultaneous determination of trace amounts of Cu^(2+), Cd^(2+) and Co^(2+) in the presence of an extremely large excess of Zn^(2+). 展开更多
关键词 on-line simultaneous determination trace polymetallic ions reagent optimization high concentration ratio
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使用沃特世的On-line SPE/LC/MS/MS技术分析饮用水源地水中的痕量优先污染物 被引量:1
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作者 Claude R Mallet 《环境化学》 CAS CSCD 北大核心 2010年第5期990-991,共2页
关键词 优先污染物 饮用水源地 on-line 技术分析 痕量 个人护理产品 欧洲科学家 兽药产品
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On-line forecasting model for zinc output based on self-tuning support vector regression and its application
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作者 胡志坤 桂卫华 彭小奇 《Journal of Central South University of Technology》 2004年第4期461-464,共4页
An on-line forecasting model based on self-tuning support vectors regression for zinc output was put forward to maximize zinc output by adjusting operational parameters in the process of imperial smelting furnace. In ... An on-line forecasting model based on self-tuning support vectors regression for zinc output was put forward to maximize zinc output by adjusting operational parameters in the process of imperial smelting furnace. In this model, the mathematical model of support vector regression was converted into the same format as support vector machine for classification. Then a simplified sequential minimal optimization for classification was applied to train the regression coefficient vector α- α* and threshold b. Sequentially penalty parameter C was tuned dynamically through forecasting result during the training process. Finally, an on-line forecasting algorithm for zinc output was proposed. The simulation result shows that in spite of a relatively small industrial data set, the effective error is less than 10% with a remarkable performance of real time. The model was applied to the optimization operation and fault diagnosis system for imperial smelting furnace. 展开更多
关键词 imperial smelting furnace support vectors regression sequential minimal optimization zinc output on-line forecasting
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Improved grey prediction model based on exponential grey action quantity 被引量:17
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作者 YIN Kedong GENG Yan LI Xuemei 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第3期560-570,共11页
With the passage of time, it has become important to investigate new methods for updating data to better fit the trends of the grey prediction model. The traditional GM(1,1) usually sets the grey action quantity as ... With the passage of time, it has become important to investigate new methods for updating data to better fit the trends of the grey prediction model. The traditional GM(1,1) usually sets the grey action quantity as a constant. Therefore, it cannot effectively fit the dynamic characteristics of the sequence, which results in the grey model having a low precision. The linear grey action quantity model cannot represent the index change law. This paper presents a grey action quantity model, the exponential optimization grey model(EOGM(1,1)), based on the exponential type of grey action quantity; it is constructed based on the exponential characteristics of the grey prediction model. The model can fully reflect the exponential characteristics of the simulation series with time. The exponential sequence has a higher fitting accuracy. The optimized result is verified using a numerical example for the fluctuating sequence and a case study for the index of the tertiary industry's GDP. The results show that the model improves the precision of the grey forecasting model and reduces the prediction error. 展开更多
关键词 exponential of grey action quantity optimal algorithm grey forecasting mathematical modeling
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Optimal EOQ Model for Deteriorating Items Considering the Incremental Quantity Discounts and Shortages 被引量:1
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作者 Zhou Yongwu Dept. of Math., Hefei University of Technology, 230009, P. R. China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1998年第1期16-23,共8页
In this present paper, a deterministic lot size model is developed for deteriorating items with incremental quantity discounts. It is assumed that shortages are permitted to occur and fully backlogged. A simple solut... In this present paper, a deterministic lot size model is developed for deteriorating items with incremental quantity discounts. It is assumed that shortages are permitted to occur and fully backlogged. A simple solution procedure is shown for determining the optimal order lot size and the optimal order cycle. A numerical example is used to illustrate how the solution procedure works. 展开更多
关键词 DETERIORATION Incremental quantity discount Shortages.
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Two-echelon inventory model with service level constraint and controllable lead time sensitive to order quantity 被引量:3
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作者 李果 关旭 +1 位作者 刘梦麒 单汩源 《Journal of Central South University》 SCIE EI CAS 2013年第11期3324-3333,共10页
The decision-making and optimization of two-echelon inventory coordination were analyzed with service level constraint and controllable lead time sensitive to order quantity.First,the basic model of this problem was e... The decision-making and optimization of two-echelon inventory coordination were analyzed with service level constraint and controllable lead time sensitive to order quantity.First,the basic model of this problem was established and based on relevant analysis,the original model could be transformed by minimax method.Then,the optimal order quantity and production quantity influenced by service level constraint were analyzed and the boundary of optimal order quantity and production quantity was given.According to this boundary,the effective method and tactics were put forward to solve the transformed model.In case analysis,the optimal expected total cost of two-echelon inventory can be obtained and it was analyzed how service level constraint and safety factor influence the optimal expected total cost of two-echelon inventory.The results show that the optimal expected total cost of two-echelon inventory is constrained by the higher constraint between service level constraint and safety factor. 展开更多
关键词 service level constraint safety factor controllable lead time sensitivity to order quantity two-echelon
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Simulation of water quantity exchange between groundwater and the Platte River water, central Nebraska 被引量:7
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作者 束龙仓 CHEN Xun-hong 《Journal of Central South University of Technology》 2002年第3期212-215,共4页
The authors demonstrate the importance of the simulation of the water quantity exchange between river water and groundwater to a better understanding of the hydrologic relations between a river and nearby aquifer wher... The authors demonstrate the importance of the simulation of the water quantity exchange between river water and groundwater to a better understanding of the hydrologic relations between a river and nearby aquifer where groundwater is pumped extensively but only seasonally. And MODFLOW is used to design the stream aquifer model in which the pumpage of more than 1000 wells was simulated. The river gaining and river losing processes were analyzed. Simulation results suggest that continuation of over extraction of groundwater will gradually increase the depletion volume in the river year after year and more depletion will occur in later years. The exchange manner between groundwater and the Platte River differs from place to place. The Platte River loses water to the adjacent aquifer in the west part of the study area, and gains water from the adjacent aquifer in the east part of the study area. 展开更多
关键词 water quantity EXCHANGE river-aquifer system the Platte River Visual MODFLOW
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An adjusted energy-saving quantity calculation method for building energy-efficient retrofit
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作者 王清勤 孟冲 《Journal of Central South University》 SCIE EI CAS 2009年第S1期265-269,共5页
Aiming at a comprehensive assessment of energy-saving retrofitting effect on existing buildings,a calculation method is developed to adjust energy-saving quantity in standard condition for comparison under the same co... Aiming at a comprehensive assessment of energy-saving retrofitting effect on existing buildings,a calculation method is developed to adjust energy-saving quantity in standard condition for comparison under the same conditions. A mathematical model,method theory and calculation steps are given. Error analysis results show that this method can be applied accurately to practical engineering projects. In a case study of energy-saving quantity assessment before and after retrofitting on a certain hospital in Shanghai,with energy simulation software TRNSYS,detailed application of this method is introduced and analyzed. The method is applied to the case of energy-saving quantity assessment to a hospital in Shanghai before and after retrofitting with the energy simulation software TRNSYS. 展开更多
关键词 ENERGY-SAVING RETROFIT adjusted ENERGY-SAVING quantity LINEAR INTERPOLATION ERROR ANALYSIS
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Study on Influencing Factors and Planning Model of Mining Quantity about Mineral Resources in Open Pit
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作者 KE Lihua CHEN Jie 《矿物学报》 CAS CSCD 北大核心 2013年第S1期41-41,共1页
According to the particularity of the open pit, the main influencing factors of mining quantity about mineral resources have been summarized systematically in life cycle and the structured hierarchical relation of its... According to the particularity of the open pit, the main influencing factors of mining quantity about mineral resources have been summarized systematically in life cycle and the structured hierarchical relation of its influencing factors has been constructed. In the light of the production process of open pit, the functional relationships between investment, mining cost and mining quantity have been defined based on the process of mining and loading so that the relation of the life cycle cost and mining quantity can be set up. And what’s more, in order to obtain the maximum economic profit of mining enterprises in life cycle, the planning model of mining quantity has been established based on the life cycle cost. The rational distribution of mining quantity will have been found on the condition of obtaining optimal solution about the planning model so as to determine scientifically the production scale of mining enterprises from the point of view of the sustainable development. 展开更多
关键词 OPEN PIT MINING quantity LIFE-CYCLE COST PLANNING model
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Critical point quantities and integrability conditions for a class of quintic systems
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作者 刘一戎 肖萍 《Journal of Central South University of Technology》 2004年第1期109-112,共4页
For a class of quintic systems, the first 16 critical point quantities are obtained by computer algebraic system Mathematica, and the necessary and sufficient conditions that there exists an exact integral in a neighb... For a class of quintic systems, the first 16 critical point quantities are obtained by computer algebraic system Mathematica, and the necessary and sufficient conditions that there exists an exact integral in a neighborhood of the origin are also given. The technique employed is essentially different from usual ones. The recursive formula for computation of critical point quantities is linear and then avoids complex integral operations. Some results show an interesting contrast with the related results on quadratic systems. 展开更多
关键词 quintic system critical point quantity integrability condition node quantity
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西部生态脆弱矿区采动水资源与生态环境效应 被引量:9
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作者 姚强岭 于利强 +2 位作者 陈胜焱 李英虎 李学华 《煤炭学报》 北大核心 2025年第2期748-767,共20页
西部生态脆弱矿区是我国重要的煤炭生产基地,当前煤炭开采规模与强度已远超其环境承载能力,极有可能造成生态环境的不可逆破坏。后煤炭开采阶段地表生态修复将是该区域面临的最突出的环境问题,而水资源在此过程中起基础配置作用,“水−... 西部生态脆弱矿区是我国重要的煤炭生产基地,当前煤炭开采规模与强度已远超其环境承载能力,极有可能造成生态环境的不可逆破坏。后煤炭开采阶段地表生态修复将是该区域面临的最突出的环境问题,而水资源在此过程中起基础配置作用,“水−环”矛盾突出。煤矿采动水资源是指因采矿活动而转移、汇集并有效储存的水资源,为人造含水层,从区域水循环的角度来看其对地表生态修复具有举足轻重的作用。在总结已有研究成果的基础上,提出了采动水资源总量及采动空间存储量的计算方法,阐述了其与覆岩结构、水文地质、煤层开采及储水空间稳定性等影响因素之间的关系,建立了包含3个方面15种参数的采动水资源潜力评价体系;分析了区域水循环模式及采动影响下的生态损伤过程,探讨了维持生态平衡所需采动水资源总量的计算方法,定义了区域最佳、合理及最低生态需水量的概念,提出了地表生态环境修复效果评价指标,构建了基于煤炭开采全周期的矿井规划设计思路及技术体系;以西部生态脆弱矿区某矿为例,阐述了区域水循环下的水量平衡/超平衡状态,评估和预测了地表生态修复效果。研究表明:即使在枯水年,当前采动水资源总量亦能为地表生态环境提供可靠、足够的水资源,生态修复等级为Ⅱ级。平年和丰年则可以在Ⅰ级水平下修复1.53~2.26倍采空区面积的地表生态环境,同时可以维持更大区域的生态系统功能完整性,比例系数在丰年最高达9.03。采动水资源总量随煤炭开采面积增大而逐级增加,在满足区域生态用水需求的前提下,将其作为战略储备资源长期储存并适时用于国防、民生、工业等方面是下一步重点研究的方向。水是区域生态环境要素改变过程中最关键的影响因素,采动水资源的保护与利用对煤炭安全高效开采与生态环境修复均具有重要的战略价值。 展开更多
关键词 区域水循环 采动水资源 生态修复 水量预测
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女性生育选择受同群育儿分工的影响吗?——基于同群参考预期约束的分析 被引量:1
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作者 郭凤鸣 文孝斌 常慧 《人口学刊》 北大核心 2025年第2期17-29,共13页
近年来我国出生人口持续下降引起了社会各界的广泛关注,大量研究聚焦女性生育选择的影响因素。随着社会的发展,生育观念也在不断变化,群体内部形成的育儿分工模式为未生育女性带来参考预期,进而影响其未来的生育选择。因此,分析同群育... 近年来我国出生人口持续下降引起了社会各界的广泛关注,大量研究聚焦女性生育选择的影响因素。随着社会的发展,生育观念也在不断变化,群体内部形成的育儿分工模式为未生育女性带来参考预期,进而影响其未来的生育选择。因此,分析同群育儿分工对女性生育选择的影响可以进一步把握影响女性生育选择的因素,并提出更具针对性的政策建议。本文建立女性生育数量的经典线性回归模型和生育选择的二元选择模型,并通过对2018年中国流动人口动态监测调查(CMDS)和2015年中国健康与营养调查(CHNS)数据进行匹配,消除同一来源数据带来的解释变量内生性问题,实证分析同群育儿分工对女性生育的影响。研究结果表明:女性承担更多照顾孩子责任的同群育儿分工模式使女性生育数量减少、二胎生育概率下降,对于不同受教育程度的女性而言,同群育儿分工对其生育选择的影响存在明显差异。相比于受教育程度较低的女性,同群育儿分工对受教育程度较高女性生育选择的负向影响更小。基于零截断计数数据模型和有序Probit模型的检验验证了主要回归结果的稳健性。异质性分析结果表明:对于不同生育观念和养育观念的女性群体而言,同群育儿分工对其生育选择的影响存在明显差异。倾向于女性承担更多的同群育儿分工对主观上认为女性就应该有孩子的女性生育的影响更小,对主观上更要求男女平等的女性生育的负向影响更大。基于调节效应模型的稳健性检验验证了异质性分析结果的稳健性。因此,通过调整群体内部育儿分工规范以提升生育率的措施是可行的。政府部门可以通过加强社会引导和相关政策支持提升男性的育儿责任,降低女性预期育儿负担,提升女性生育意愿,同时对于持保守态度的女性,应提升其改变传统分工约束的信心,从认知的角度改变育儿分工规范,提升生育率。育儿分工的调整不仅可以降低抚养孩子为女性带来的负向影响,进而促进生育,而且有助于低教育程度女性家庭和社会地位的提升,并进一步提升其生育选择的自愿性,促进人口的健康发展。 展开更多
关键词 育儿分工 生育选择 生育数量 同群参考
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基于信息量模型的黑山峡地区滑坡易发性风险评价 被引量:3
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作者 王炳亮 裴超 +2 位作者 李宝泉 石慧群 林兴 《人民黄河》 北大核心 2025年第1期134-140,共7页
滑坡是黄河黑山峡地区的主要地质灾害之一,在黑山峡水利枢纽建设前期工作中开展黑山峡地区滑坡易发性评价显得尤为必要。基于黑山峡地区地质条件、气候、人类活动等调查资料,选取高程、坡度、曲率、地层岩性、与断层的距离、与水系的距... 滑坡是黄河黑山峡地区的主要地质灾害之一,在黑山峡水利枢纽建设前期工作中开展黑山峡地区滑坡易发性评价显得尤为必要。基于黑山峡地区地质条件、气候、人类活动等调查资料,选取高程、坡度、曲率、地层岩性、与断层的距离、与水系的距离、NDVI(归一化差分植被指数)、与道路的距离、降水量9个因子作为滑坡易发性评价指标,采用信息量模型进行滑坡易发性评价,通过对各因子的分级权重进行计算,得到滑坡易发性信息量值;通过对滑坡易发性信息量进行叠加与分区,绘制黑山峡地区滑坡易发性分区图,确定危险区域。结果表明:黑山峡地区滑坡灾害极高易发区位于东北部中卫市沙坡头区、南部靖远县以及主要河流与道路沿线,这些地区地层岩性较软弱,大多为砂、黄土等,在河流冲积与人类活动的影响下极易发生地表斜坡失稳。 展开更多
关键词 滑坡 易发性 风险评价 信息量模型 黑山峡地区
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数字政府建设有助于促进劳动就业吗?——来自中国上市公司的证据 被引量:5
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作者 陈东 刘威 《南方经济》 北大核心 2025年第2期26-46,共21页
在当前“稳就业”的重大现实需求下,数字政府建设有望成为实现稳定就业目标的新思路。文章在使用投入产出表测算数字政府建设水平的基础上,采用2007—2020年中国上市公司数据,深入考察了数字政府建设对企业劳动就业的影响及其作用机制,... 在当前“稳就业”的重大现实需求下,数字政府建设有望成为实现稳定就业目标的新思路。文章在使用投入产出表测算数字政府建设水平的基础上,采用2007—2020年中国上市公司数据,深入考察了数字政府建设对企业劳动就业的影响及其作用机制,并进一步讨论数字政府建设对劳动资源配置效率的影响。研究结果表明,数字政府建设能够显著增加企业的劳动就业数量,该结论在经过一系列稳健性检验后依然成立,且这一影响在私有企业、缺乏政治关联的企业、成长期企业和劳动密集型企业中更加明显;数字政府建设不仅能通过削减非生产性支出、缓解融资约束和降低经济不确定性扩大企业的生产投资和劳动需求,还能通过拓展业务范围发挥岗位创造效应,共同增加企业就业数量;数字政府建设还有助于缓解企业的雇佣不足,提高企业内的劳动资源配置效率,并通过增强市场竞争优化企业间的劳动要素分配。文章评估数字政府建设的就业效应,对强化政府数字化建设、实现“稳就业”政策目标具有重要的现实意义。 展开更多
关键词 数字政府 市场环境 就业数量 劳动资源配置效率
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现代汉语名量词表量功能考察 被引量:1
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作者 蒋静忠 穆林芳 《汉语学习》 北大核心 2025年第2期25-34,共10页
国内外已有学者提出现代汉语名量词存在分类词和其他量词的对立。本文通过考察现代汉语中的“数量名”结构,发现其在表量功能上呈现出从计数到计量的连续统。根据这个连续统,可以把现代汉语名量词分为计数量词和计量量词两大类。其中,... 国内外已有学者提出现代汉语名量词存在分类词和其他量词的对立。本文通过考察现代汉语中的“数量名”结构,发现其在表量功能上呈现出从计数到计量的连续统。根据这个连续统,可以把现代汉语名量词分为计数量词和计量量词两大类。其中,分类词既包含计数量词,也包含计量量词。考察发现,现代汉语计量量词还存在计量功能典型程度的差异,据此可以分为典型计量量词、较典型计量量词、非典型计量量词三类。三类计量量词在计量维度上存在一定的倾向性,典型计量量词倾向于计量一维,较典型计量量词和非典型计量量词倾向于计量三维。 展开更多
关键词 名量词 表量功能 计量维度 倾向性
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基于栅格信息量法的区域地面沉降风险评价——以河北省沧州市为例 被引量:1
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作者 刘波 李诗浓 +3 位作者 李伟 王文鹏 鲁程鹏 束龙仓 《吉林大学学报(地球科学版)》 北大核心 2025年第3期919-929,共11页
地面沉降风险诱发因素复杂、空间分布差异较大,为科学开展地面沉降风险评估工作,本研究提出栅格信息量法的地面沉降风险评价方法。首先通过计算各栅格化评价指标与地表形变量之间的信息量值,定量表征两者之间的关联程度;然后构建包含危... 地面沉降风险诱发因素复杂、空间分布差异较大,为科学开展地面沉降风险评估工作,本研究提出栅格信息量法的地面沉降风险评价方法。首先通过计算各栅格化评价指标与地表形变量之间的信息量值,定量表征两者之间的关联程度;然后构建包含危险性、脆弱性和暴露度3个方面共11项指标的评价体系;再采用主客观综合赋权方法确定权重并计算风险值,通过受试者工作特征曲线进行的可靠性检验后进行风险评价;最后将上述方法应用于2022年河北省沧州市地面沉降风险评价。结果表明:相较于脆弱性评价指标,危险性和暴露度评价指标的栅格信息量值偏高。危险性评价指标中,年平均地面沉降速率为高风险指标,当年平均地面沉降速率为-127~-17 mm/a时,信息量值为1.538,对地面沉降风险的危险性最大;暴露度评价指标中,人口密度为高风险指标,当人口密度>5430人/km^(2)时,信息量值为1.923,对地面沉降风险的暴露度最高。沧州市1 km空间分辨率下地面沉降风险等级为高、较高、中、较低、低五个等级的区域面积占比分别为9.90%、24.91%、31.12%、23.05%、11.02%;高风险区主要集中在沧州市主城区、肃宁县、黄骅市等区域,中风险地区主要分布于沧州市西部区域。栅格信息量法对沧州市地面沉降风险评价的可靠性较好,准确度达到0.714。 展开更多
关键词 风险评价 栅格信息量法 地面沉降 主客观组合赋权 河北省沧州市
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专精特新战略能否促进企业创新的“增量提质”? 被引量:3
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作者 王海花 王莹 李树杰 《系统管理学报》 北大核心 2025年第2期494-508,共15页
基于2013~2021年中国沪深A股上市的专精特新“小巨人”企业数据,探究专精特新战略及其各维度对企业创新数量和创新质量的作用效果,分析企业数字化转型程度在上述关系中的调节作用。研究结果表明:专精特新战略、专业化战略和新颖化战略... 基于2013~2021年中国沪深A股上市的专精特新“小巨人”企业数据,探究专精特新战略及其各维度对企业创新数量和创新质量的作用效果,分析企业数字化转型程度在上述关系中的调节作用。研究结果表明:专精特新战略、专业化战略和新颖化战略对企业创新数量和质量均存在正向影响,精细化战略则不利于企业创新质量的提升;企业数字化转型程度在专精特新战略与企业创新数量及质量关系中起正向调节作用,其不仅正向调节专业化战略与企业创新质量的关系,还显著增强了新颖化战略对企业创新数量及质量的促进作用。研究结论为中小企业进行“专精特新”转型升级和创新高质量发展提供有价值的参考。 展开更多
关键词 专精特新战略 创新数量 创新质量 数字化转型
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