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Relationship between Inter Canine Width and Inter Alar Width, Inter Commissural Width, and Inter Canthal Distance: A Pilot Study
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作者 Grevisse Bindele Ndombolo Augustin Mantshumba Milolo +5 位作者 Fidele Nyimi Bushabu Em Kalala Kazadi Pierrot Kumpanya Ntumba Jean Marie Kayembe Bukama Elias Lubadi Tshilumba Jean Paul Sekele Isouradi 《Open Journal of Stomatology》 2024年第6期279-290,共12页
The aim of this study was to determine the relationship between inter canine width (ICW) and inter alar width (IAW), inter commissural width (ICoW), and inter canthal distance (ICaD) in Bantu population. Materials and... The aim of this study was to determine the relationship between inter canine width (ICW) and inter alar width (IAW), inter commissural width (ICoW), and inter canthal distance (ICaD) in Bantu population. Materials and Methods: It was a pilot study included all participants who were aged at least 18 years, without a history of orthodontics treatment from Prosthodontics Department, Faculty of Dental Medicine, University of Kinshasa. The Ethics committee of the National Center of Research for Dental Sciences in DR Congo approved the study protocol (CNRSB 1504.218). The participants medical records were obtained from the interview and dental examination. Nature of the study was explained with participant information sheet, and an informed consent of all participants was obtained. The inclusion criteria were no missing maxillary and mandibular teeth, no diastema, and no anterior restorations, 18 years old before enrollment in the study. The exclusion criteria were inability to meet the above requirements, pregnancy, and refusal to participate in the study. The inter-canine width (ICW), inter alar width (IAW), inter canthal distance (ICaD) and inter-commissural width (ICoW) of each participant were measured with a digital Vernier caliper (Mitutoyo, UK Ltd.,) (0.01 mm) three times and the average value was recorded. The inter canthal distance (ICaD) was measured without applying pressure by bringing the recording parts of the caliper just in contact with the medial angle. The inter alar width (IAW) was marked with a fine marked pencil on the widest outer surface of the alae of the nose on either side or width. Those two points were measured without applying pressure by bringing the recording parts of the caliper just in contact with the outer surface. The participant was told to stop breathing shortly to avoid any change in shape of the nose. The inter-commissural width (ICoW) was determined by measuring the maxillary lip vermilion from commissure to commissure without the application of pressure on the tissue in the relaxed state. The inter-canine width (ICW) was measured indirectly using a dental floss. A dental floss was marked on one end prior to placement in the mouth. Using that point as reference, the dental floss was circumference along the curvature of the anterior dentition such that it passed along the contact point of all the teeth. The distal end of the canine teeth on both sides was then marked on the floss while it was stretched in the patients mouth. Floss was marked on both sides with the marker pencil. The distance between the two proximal contact points was measured and recorded. Data, analysis and validation were performed by the SPSS software (version 22.0, IBM SPSS Statistics, Chicago, IL, USA). Unpaired t-test was used, of Kolmogorov-Smirnov test. Analysis of variance (ANOVA) test was used to test for comparability between socio-demographic characteristics dental measurements. Pearsons correlation coefficients test was calculated to determine the relationship between facial and dental parameters. Significance was set at P 0.01. Results: Of 314 participants enrolled, 202 were included. The age ranged from 18 to 68 years, with a mean age of 40.62 12.99 years. Although the Pearsons correlation coefficients were negative. Ninety-three participants (46%) were men and one hundred and nine (54%) were women. The overall mean age was 40.62 12.99 years. Facial and dental measurements were greater in women than men with significant differences for ICW (p = 0.04). However, no significant difference was seen between men and women for IAW, ICaD and ICoW (p = 0.44, p = 0.23, p = 0.31 respectively). The correlation including Pearsons correlation coefficient and P-values for all participants is not demonstrated. Conclusion: Within the limitations of this study, the results suggest that IAW, ICaD and ICoW cannot be used as a preliminary method for determining the width of the maxillary for anterior teeth for edentulous patients. 展开更多
关键词 RELATIONSHIP inter-Canine Width inter Alar Width inter Canthal Distance inter Commissural Width
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Inter-Row Spacing of PV Power Plant
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作者 Laiqat Ali Khan 《Energy and Power Engineering》 2024年第3期121-129,共9页
When designing a solar power plant, it is much more important to avoid the shadow on the PV Panels. As the shadow falls on the PV Panels;it significantly reduces the generation of required power as planned and designe... When designing a solar power plant, it is much more important to avoid the shadow on the PV Panels. As the shadow falls on the PV Panels;it significantly reduces the generation of required power as planned and designed. This research paper and case study will help a lot to avoid shadow, especially when selecting inter-row spacing between the strings of solar power plants. 展开更多
关键词 inter Row Spacing Shadow Effect on PV Plant Hot Spot Heating
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Inter-Fraction Analysis of One Week Hypo-Fractionation of Deep Inspiration Breath Hold (DIBH) Technique for Left Sided Breast Cancer Radiation Treatment
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作者 Ntombela N. Lethukuthula Mathuthu Manny Nyathi Mpumelelo 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2024年第3期41-52,共12页
The aim of this study was to investigate the inter-fraction variations, patient comfort and knowledge at Charlotte Maxeke Johannesburg Academic Hospital (CMJAH). The differences in set-up that occurred between treatme... The aim of this study was to investigate the inter-fraction variations, patient comfort and knowledge at Charlotte Maxeke Johannesburg Academic Hospital (CMJAH). The differences in set-up that occurred between treatment sessions for the left sided breast patients were observed and recorded. Measurements of routine set-up variation for 24 patients were performed by matching the cone beam computed tomography (CBCT) and the planning computed tomography (CT). Scans of all five fractions per patient were used to quantify the setup variations with standard deviation (SD) in all the three directions (anterior posterior, left right, and superior inferior). The patients DIBH comfort and knowledge was also evaluated. The average translational errors for the anterior posterior (AP, z), left-right (LR, x), and Superior-inferior (SI, y) directions were 0.40 cm, 0.40 cm, and 0.40 cm, respectively. The translation variation of the three directions showed statistical significance (P < 0.05). On comfort and knowledge investigation, among all participants, 80% moderately agreed that the therapist’s instructions for operating the deep inspiration breath hold (DIBH) technique were easy to understand, and 63.33% indicated that their comfort with the DIBH technique was neutral or average. The inter-fraction variations in patients with left-sided breast cancer were qualitatively analyzed. Significant shifts between CBCT and planning CT images were observed. The daily treatment verification could assist accurate dose delivery. 展开更多
关键词 Breast Cancer Deep Inspiration Breath Hold Hypo-Fractionation inter-Fraction
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基于Inter.iamb-Tabu算法的区域滑坡敏感性评价 被引量:1
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作者 尹超 李仲波 +2 位作者 张凯 王绍平 郭兵 《山地学报》 CSCD 北大核心 2023年第4期608-620,共13页
确定滑坡敏感性概率的空间分布,可为滑坡防治政策制定和土地利用规划提供科学依据。由于成灾环境的空间差异和滑坡机理的复杂性,基于不同逻辑架构(物理模型、理论模型等)的滑坡敏感性评价针对特定孕灾环境,无法提前确定最优数学评价模型... 确定滑坡敏感性概率的空间分布,可为滑坡防治政策制定和土地利用规划提供科学依据。由于成灾环境的空间差异和滑坡机理的复杂性,基于不同逻辑架构(物理模型、理论模型等)的滑坡敏感性评价针对特定孕灾环境,无法提前确定最优数学评价模型,而基于深度学习法的、融合多种模型的混合算法能较好地解决这个问题。本文以山东省淄博市博山区为研究区域,基于单因素Logistic回归法筛选了滑坡致灾因子,通过频率比法对致灾因子进行了分级;对4种基于贝叶斯网络的改进算法(MMHC、MMPC-Tabu、Fast.iamb-Tabu、Inter.iamb-Tabu)进行验证,引入错误指数确定了建模效果最佳的算法;计算了博山区774570个栅格的滑坡敏感性概率,绘制了博山区滑坡敏感性分布图;基于GIS的空间叠加和栅格计算器功能,对比了各模型的滑坡敏感性评价结果。研究结果表明:(1)基于Inter.iamb-Tabu开展博山区滑坡敏感性建模时效果最佳。该模型包含10个节点(9个致灾因子节点和1个结局节点)、14条有向边。研究区域可划分为极高敏感区、高敏感区、中敏感区、低敏感区和极低敏感区,分别占总面积的7.30%(49.80km^(2))、16.50%(112.56km^(2))、26.10%(178.05km^(2))、33.20%(226.49km^(2))和16.90%(115.29km^(2)),分别有67处、22处、7处、2处和1处滑坡位于上述敏感区。(2)MMHC、MMPC-Tabu和Fast.iamb-Tabu模型在训练时易舍弃样本中部分因子的特征信息,以达到模型整体精度最优的目的。研究成果可为山东省淄博市博山区滑坡防治提供理论依据,采用的研究方法同样适用于类似地区。 展开更多
关键词 滑坡敏感性评价 致灾因子 贝叶斯网络 inter.iamb-Tabu算法
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Long-term and short-term stability characteristics of receiver inter system bias for BDS3/BDS2
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作者 Jingxuan Guo Weiping Jiang +2 位作者 Yan Chen Xincheng Ma Hua Chen 《Geodesy and Geodynamics》 CSCD 2023年第2期143-149,共7页
The study of inter-system bias(ISB)is important for multi-system fusion and the performance of different signal compatibility.In this paper,the stability of ISB at the BDS3/BDS2 receiver end is calculated and analyzed... The study of inter-system bias(ISB)is important for multi-system fusion and the performance of different signal compatibility.In this paper,the stability of ISB at the BDS3/BDS2 receiver end is calculated and analyzed for different time spans(DOY 060~090 in 2021)from a total of 31 MGEX and iGMAS stations.We adopted two estimation strategies,random walk and constant approach,using the precision products of orbit and clock bias provided by WUM,the influence of which on ISB was also analyzed.Our results showed that the ISB value varied little within a day,and the mean of daily ISB standard deviation was only 0.037 m when the observation condition was good.The signal reception was continuous,indicating a high ISB stability for one day.If extending the time series to one month,however,the ISB standard deviation calculated by constant approach,in which a constant ISB is estimated on a daily basis was about 0.1 m,and the results of adjacent days were not continuous,with no apparent pattern.Concerning the random walk approach,the obtained ISB time series also had a jump,and the conclusion was the same as that of the constant strategy.Besides,receiver types showed a strong regularity in ISB numerical situation,and the distribution of ISB values corresponding to the same receiver type was relatively close.Therefore,we conclude that the ISB parameters remain stable in the short term(one day)and less stable in the long-term period.It is recommended that the ISB term should be set as a constant estimate every day in BDS3/BDS2 solutions,regardless of receiver type consistency. 展开更多
关键词 BDS3 BDS2 inter system bias Stability analysis Receiver type
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美国丽人 INTERATIONAL AUTO SHOW——2004纽约车展
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《中国商界》 2004年第6期28-29,31-32,共4页
2005 Jaguar xJ LWB 新的XJ比以前的XJ轻了约200公斤,而比最接近的对手,也轻了有100公斤。这个重量上的优势也同样的在LWB型号上得到了体现,它亦是同级中最轻的。如同最新一代的标准轴距XJ,新XJLWB也共享了先进的铝质结构的所有优势,包... 2005 Jaguar xJ LWB 新的XJ比以前的XJ轻了约200公斤,而比最接近的对手,也轻了有100公斤。这个重量上的优势也同样的在LWB型号上得到了体现,它亦是同级中最轻的。如同最新一代的标准轴距XJ,新XJLWB也共享了先进的铝质结构的所有优势,包括轻重量以及突出的车身强度增强。 展开更多
关键词 美国丽人 全轮驱动 前轮驱动 interationAL AUTO SHOW AMG 车展 纽约 美国
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Tricube Weighted Linear Regression and Interquartile for Cloud Infrastructural Resource Optimization
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作者 Neema George B.K.Anoop Vinodh P.Vijayan 《Computer Systems Science & Engineering》 SCIE EI 2023年第6期2281-2297,共17页
Cloud infrastructural resource optimization is the process of precisely selecting the allocating the correct resources either to a workload or application.When workload execution,accuracy,and cost are accurately stabi... Cloud infrastructural resource optimization is the process of precisely selecting the allocating the correct resources either to a workload or application.When workload execution,accuracy,and cost are accurately stabilized in opposition to the best possible framework in real-time,efficiency is attained.In addition,every workload or application required for the framework is characteristic and these essentials change over time.But,the existing method was failed to ensure the high Quality of Service(QoS).In order to address this issue,a Tricube Weighted Linear Regression-based Inter Quartile(TWLR-IQ)for Cloud Infrastructural Resource Optimization is introduced.A Tricube Weighted Linear Regression is presented in the proposed method to estimate the resources(i.e.,CPU,RAM,and network bandwidth utilization)based on the usage history in each cloud server.Then,Inter Quartile Range is applied to efficiently predict the overload hosts for ensuring a smooth migration.Experimental results show that our proposed method is better than the approach in Cloudsim under various performance metrics.The results clearly showed that the proposed method can reduce the energy consumption and provide a high level of commitment with ensuring the minimum number of Virtual Machine(VM)Migrations as compared to the state-of-the-art methods. 展开更多
关键词 Cloud infrastructure tricube weighted linear regression inter quartile CPU RAM network bandwidth utilization
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莱卡公司再度亮相Intertextile,用“新”诠释创新实力
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《纺织导报》 CAS 2023年第5期12-12,共1页
8月30日,中国国际纺织面料及辅料(秋冬)博览会(Intertextile)正式落下帷幕。作为暌违两年的再度回归,The LYCRA Company(以下简称“莱卡公司”)携众多新品强势亮相,重磅推出LYCRA■ ADAPTIV fiber(莱卡■智合智纤)系列新产品。为了满足... 8月30日,中国国际纺织面料及辅料(秋冬)博览会(Intertextile)正式落下帷幕。作为暌违两年的再度回归,The LYCRA Company(以下简称“莱卡公司”)携众多新品强势亮相,重磅推出LYCRA■ ADAPTIV fiber(莱卡■智合智纤)系列新产品。为了满足市场对耐用服装的需求,提供更具尺码包容性、更高舒适度和更强功能的服装。 展开更多
关键词 创新实力 高舒适度 纺织面料 博览会 inter 包容性
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对有关电能计量若干问题的思考 被引量:2
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作者 赵伟 赵成 +3 位作者 李世松 仝霞 刘坚 李雪城 《电测与仪表》 北大核心 2024年第1期1-7,共7页
文中基于论证和较全面分析,就不同场景下电能计量所关注的截然不同的问题、更好利用大数据去构建电能表检验新方法、动态电能计量研究面临新挑战、关注超谐波电能计量、不宜将电能计量装置与电能表简单划等号,以及测量准确度不同于测量... 文中基于论证和较全面分析,就不同场景下电能计量所关注的截然不同的问题、更好利用大数据去构建电能表检验新方法、动态电能计量研究面临新挑战、关注超谐波电能计量、不宜将电能计量装置与电能表简单划等号,以及测量准确度不同于测量精度等六个问题,阐述了作者的观点和认识,旨在对开展相关研究,以及更清楚理解相关测量方法及概念等起到促进作用。 展开更多
关键词 智能电能表 电能计量 间谐波 超高次谐波 虚拟标准
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热处理对选区激光熔化Al-Mn-Mg-Sc-Zr合金力学性能和腐蚀行为的影响 被引量:1
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作者 邓英 曹俊昌 +4 位作者 赖毅 郭一帆 梁美婵 潘清林 徐国富 《中国有色金属学报》 EI CAS CSCD 北大核心 2024年第4期1240-1251,共12页
以Al-4.77Mn-1.37Mg-0.67Sc-0.25Zr(质量分数,%)合金粉末为原料,在激光功率330 W和扫描速率700 mm/s下进行选区激光熔化(Selective laser melting,SLM)形成SLM Al-Mn-Mg-Sc-Zr合金,结合慢应变速率拉伸实验、电化学测试、析氢浸泡实验及... 以Al-4.77Mn-1.37Mg-0.67Sc-0.25Zr(质量分数,%)合金粉末为原料,在激光功率330 W和扫描速率700 mm/s下进行选区激光熔化(Selective laser melting,SLM)形成SLM Al-Mn-Mg-Sc-Zr合金,结合慢应变速率拉伸实验、电化学测试、析氢浸泡实验及显微组织表征手段,分析了(350℃,8 h)热处理对SLM Al-Mn-Mg-Sc-Zr合金力学性能和腐蚀行为的影响。结果表明:SLM Al-Mn-Mg-Sc-Zr合金力学性能优异,抗拉强度、屈服强度和伸长率分别为423 MPa、376 MPa和25.1%。热处理后,SLM Al-Mn-Mg-Sc-Zr合金晶内析出大量针棒状纳米Al_(6)Mn相,抗拉强度和屈服强度分别提升至509 MPa和478 MPa。此外,SLM Al-Mn-Mg-Sc-Zr合金具有良好的耐蚀性能,热处理可以促进SLM Al-Mn-Mg-Sc-Zr合金的钝化,在-0.5 V极化电位时出现钝化台阶,降低SLM Al-Mn-Mg-Sc-Zr合金的电流密度,增加SLM Al-Mn-Mg-Sc-Zr合金的阳极极化率,使SLM Al-Mn-Mg-Sc-Zr合金的平均析氢速率从0.242 mL/(cm^(2)·h)降至0.216 mL/(cm^(2)·h),应力腐蚀敏感因子从3.379%降至0.405%。与此同时,热处理也促进了晶内微米富Si相以及晶界富Mn相和Mg相的析出,增加了SLM Al-Mn-Mg-Sc-Zr合金点蚀形核位置,增大了SLM Al-Mn-Mg-Sc-Zr合金的晶界电化学成分非均匀性,降低了SLM Al-Mn-Mg-Sc-Zr合金的点蚀和晶间腐蚀抗力。 展开更多
关键词 选区激光熔化 热处理 应力腐蚀 晶间腐蚀 电化学 显微组织
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Research progress on inter-monthly winter temperature variation in East Asia and climate prediction
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作者 Ke Fan Hongqing Yang Haixia Dai 《Atmospheric and Oceanic Science Letters》 CSCD 2023年第5期8-16,共9页
近年来,东亚冬季气温的月际间变化十分显著,冬季不同月份或不同阶段之间极端冷暖事件的转折或交替频发.由于月际间变化常常被季节平均掩盖,东亚冬季气候预测面临众多的挑战.因此,亟需研究东亚冬季气温月际间变化的特征和机理,明确其可... 近年来,东亚冬季气温的月际间变化十分显著,冬季不同月份或不同阶段之间极端冷暖事件的转折或交替频发.由于月际间变化常常被季节平均掩盖,东亚冬季气候预测面临众多的挑战.因此,亟需研究东亚冬季气温月际间变化的特征和机理,明确其可预测性和预测来源,进而研制考虑月际变化的东亚冬季气温的有效预测方法和预测模型.本文回顾了过去5年对东亚冬季气温月际间变化的主要特征,物理过程,机制,可预测性和预测的研究进展,同时考虑了多个与气温相联系统的变化,包括冬季风,西伯利亚高压,平流层极涡.本文也进一步讨论了未来的研究前景. 展开更多
关键词 月际间转折变化 冬季气温 东亚 冬季风 可预测性
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籼粳亚种间育性位点分型及籼粳杂交稻育性位点模式研究
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作者 陈明亮 曾细华 +6 位作者 沈雨民 罗世友 胡兰香 熊文涛 熊焕金 吴小燕 肖叶青 《中国水稻科学》 CAS CSCD 北大核心 2024年第4期386-396,共11页
【目的】了解我国籼稻、粳稻材料及籼粳杂交稻组合中亚种间育性位点的分布,建立实现亚种间育性亲和所需遗传位点模式,探索新的籼粳杂交稻组合模式,为亚种间亲和材料改良和籼粳育性亲和分子设计育种打下基础。【方法】通过筛选得到育性... 【目的】了解我国籼稻、粳稻材料及籼粳杂交稻组合中亚种间育性位点的分布,建立实现亚种间育性亲和所需遗传位点模式,探索新的籼粳杂交稻组合模式,为亚种间亲和材料改良和籼粳育性亲和分子设计育种打下基础。【方法】通过筛选得到育性位点的籼粳分型标记对我国水稻材料进行育性位点的籼粳分型检测,挑选部分籼稻、粳稻亲本进行杂交并统计分析F1代花粉育性和结实率。【结果】籼稻和粳稻之间在所有育性位点均存在少量相互渗入。由于籼稻育性位点渗入,粳稻可以分为Ⅰ型(所有位点均为粳型)和Ⅱ型(Sc^(i)、Sd^(i)和Se^(i),上标i代表来自籼稻)。S5不亲和时籼粳杂交稻结实率约为50%,亲和时结实率约为80%。Sa、Sb、Sc或Sd单个位点杂合对于花粉育性影响较小,但Se/pf12/RHS12单个位点杂合时显著降低花粉育性。籼粳杂交稻材料检测结果表明其育性位点的基本模式是S5和部分花粉育性位点纯合/亲和。带有S5^(n)的籼稻两系不育系深08S与粳稻Ⅱ型材料的杂交F_(1)代的花粉育性和结实率正常。【结论】S5是控制雌配子育性的核心位点。影响雄配子育性的位点具有累加效应,其中Se可能是不可缺少的重要位点。S5+Se与Sa、Sb、Sc、Sd任意两个纯合位点可能是实现籼粳亚种间育性亲和的基本遗传位点模式。以广亲和两系籼稻不育系为母本,常规粳稻为父本的“籼不粳恢”籼粳杂交模式是一个可行的亚种间组合模式。 展开更多
关键词 亚种间育性位点 分型 籼粳杂交稻 育性位点模式
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部际信用治理合作备忘录:性质、效力与优化 被引量:1
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作者 李海平 孙媛 《北京航空航天大学学报(社会科学版)》 2024年第3期30-38,共9页
合作备忘录是部际信用合作治理的重要方式。不同于行政规范性文件,合作备忘录既是公法协定中的部际协定,也是一种契约治理形态。合作备忘录遵循契约相对性一般原理,具有相对效力,但这种效力相对性也是相对的。由于科层制特有的权力结构... 合作备忘录是部际信用合作治理的重要方式。不同于行政规范性文件,合作备忘录既是公法协定中的部际协定,也是一种契约治理形态。合作备忘录遵循契约相对性一般原理,具有相对效力,但这种效力相对性也是相对的。由于科层制特有的权力结构与行政服从义务、不完善的信用立法、对个人利益的保护等,合作备忘录的效力溢出至地方公权力主体和相对人。合作备忘录具有补充信用立法、强化行政协助、促进参与式治理等优势,也存在冲击法律体系、违反法律保留原则、规避监督、缺乏合作保障等不足,因而需从合法性、规范性、民主性等方面加以优化。 展开更多
关键词 合作备忘录 部际 契约 相对效力 信用
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北京“新三代家庭”育儿模式下的儿童友好型城市规划策略 被引量:1
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作者 甘霖 邱红 加雨灵 《规划师》 北大核心 2024年第1期10-16,共7页
回溯儿童友好城市的理念起源,借鉴家庭社会学对于当代抚育结构的经典研究见解,认识到建设儿童友好城市不能仅关注儿童个体,而必须以家庭为完整单元,映射到由全龄人群组成的社会生态系统深部。通过面向北京育儿家庭进行大样本问卷调查,... 回溯儿童友好城市的理念起源,借鉴家庭社会学对于当代抚育结构的经典研究见解,认识到建设儿童友好城市不能仅关注儿童个体,而必须以家庭为完整单元,映射到由全龄人群组成的社会生态系统深部。通过面向北京育儿家庭进行大样本问卷调查,提炼当前北京育儿家庭成员之间亲职分配的主流模式,认识到由代际协作育儿纽带联结的“新三代家庭”已经构成了当前北京最典型的家庭育儿模式。这一认知有助于定位超大城市儿童友好政策输出的侧重领域,避免儿童友好城市创建走向千城一面。通过深入挖掘这一典型模式下“双职工中青年”“银发育儿族”“多孩家庭子女”等人群需求,提出6点促进儿童与家人共享城市服务的策略。 展开更多
关键词 儿童友好城市 家庭友好城市 新三代家庭 隔代抚育
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南水北调西线工程水源区可调水量“十问” 被引量:2
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作者 胡鹏 王浩 +13 位作者 赵勇 宁远 蒋云钟 刘欢 曾庆慧 杨泽凡 周毓彦 董宁澎 闫龙 阿膺兰 张丰博 唐家璇 王玉莲 王建华 《中国工程科学》 CSCD 北大核心 2024年第2期210-223,共14页
南水北调西线工程是我国“四横三纵”国家水网主骨架尚待建设的最后一环,而水源区可调水量是西线工程规划论证面临的焦点和难点问题。本文从水资源本底条件与演变趋势,生态环境与经济社会发展需水,调蓄水库与输水工程规模,调水对水源区... 南水北调西线工程是我国“四横三纵”国家水网主骨架尚待建设的最后一环,而水源区可调水量是西线工程规划论证面临的焦点和难点问题。本文从水资源本底条件与演变趋势,生态环境与经济社会发展需水,调蓄水库与输水工程规模,调水对水源区及其下游水资源开发利用、水生态环境、水力发电、航运等方面影响的角度,提出了与水源区可调水量相关的10个问题;以长江上游分布式水文模型为基础,建立了南水北调西线工程水源区可调水量模拟分析模型,力图系统、定量地回答所提问题。本文的主要研究结论有:在仅考虑满足水源区河道内外生态环境和经济社会需水的前提下,“上线+下线”组合方案多年平均可调水量为1.59×10^(10)m^(3),“完全下线”方案在建设岗托水库进行联调时,多年平均可调水量将达到1.74×10^(10)m^(3);在综合考虑调水对水源区水平衡、水力发电和航运影响及其可接受程度后,南水北调西线水源区可调水量为1.22×10^(10)~1.26×10^(10)m^(3)。长远来看,应谋划西南片区水网与国家水网主骨架、“大动脉”的连接与融合,在减小南水北调西线工程调水影响的同时,提高南水北调西线工程的整体供水能力以及对气候变化等外部条件的适应性。 展开更多
关键词 南水北调西线工程 水源区 可调水量 生态需水 跨流域调水
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以政府间事权划分为统领谋划推进新一轮财税体制改革 被引量:2
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作者 周波 王健 艾思源 《东北财经大学学报》 2024年第3期53-67,共15页
党的十八大以来,中国财税体制改革取得了巨大进展,但距离建立现代财税体制要求仍有差距。未从根本上理顺中央与地方政府事权、事责关系,以及由此产生的政府间事权和支出责任不相适应、政府间事权和财力不相匹配问题,是影响中国财税体制... 党的十八大以来,中国财税体制改革取得了巨大进展,但距离建立现代财税体制要求仍有差距。未从根本上理顺中央与地方政府事权、事责关系,以及由此产生的政府间事权和支出责任不相适应、政府间事权和财力不相匹配问题,是影响中国财税体制改革纵深推进的核心因素。谋划新一轮财税体制改革,亟须以推进政府间事权划分为统领,在明晰划分和配置政府间事权、事责、支出责任的基础上,建立现代财政制度,为加快中国式现代化进程提供财政支撑。 展开更多
关键词 政府间事权划分 财税体制改革 财政体制
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The Inter-Annual Variability of Rainfall Onset and Its Implication on Crop Planting in Selected East Africa Countries
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作者 Isack Baliyendeza Yonah Philemon Henry King’uza +3 位作者 Ladislaus Benedict Chang’a Mecklina Merchades Babyegeye Henry Fatael Mahoo Agnes Lawrence Kijazi 《American Journal of Climate Change》 2023年第2期268-291,共24页
The inter-annual variability of rainfall onset and crop replanting in East Africa (EA) was assessed using daily estimated rainfall data from climate hazard group infrared precipitation (CHIRPS Ver2.0) and monthly Sea ... The inter-annual variability of rainfall onset and crop replanting in East Africa (EA) was assessed using daily estimated rainfall data from climate hazard group infrared precipitation (CHIRPS Ver2.0) and monthly Sea Surface Temperature (SST) indices [Indian Ocean Dipole (IOD) and El-Ni?o Southern Oscillation (ENSO) at NINO3.4 region] from the National Center for Environmental Prediction (NCEP) and the National Center for Atmospheric Research (NCAR). The data covered a period of 40 years from1981 to 2020. The methods of cumulative of daily mean rainfall, percentage of onset date departure (PODD), Mann-Kendall (MK) trend test, student t-test, and correlation were applied in the analysis. The results showed that early onset with dry spell (WDS) consideration frequently occurs in Uganda between the first and second dekads of September, while late rainfall onset WDS occurs in the first and second dekads of December over central and Northern Kenya as well as in the Northeastern highlands, parts of the northern coast and unimodal regions in Tanzania. Rainfall onset with no dry spell (WnDS) portrayed an average of 10 days before the occurrence of true onset WDS, with maximum onset departure days (ODD) above 30 days across the Rift Valley area in Kenya and the Northeastern highlands in Tanzania. The high chance of minimum ODD is seen over entire Uganda and the area around Lake Victoria. However, few regions, such as Nakuru (Kenya) Gulu and Kibale (Uganda), and Gitega (Burundi), revealed a slight positive linear trend while others showed negative trend. Significant positive patterns for correlation between onset WDS and SST indices (IOD and NINO 3.4) were discovered in Northern and Northeastern Kenya, as well as areas along the Indian Ocean (over Tanzania’s Northern Coast). Inter-annual relationship between onset dates WDS and IOD (NINO3.4) indices exhibits a high correlation coefficient r = 0.23 (r = 0.48) in Uganda and r = 0.44 (r = 0.36) in Kenya. On the other hand, a negative correlation was revealed over Burundi and Tanzania (over a unimodal region). A high percentage of PODD was observed, ranging from 40% to 70% over the Rift Valley in Kenya and at the Northeastern highlands in Tanzania. However, a strong PODD above 70% was observed over Tanga and the Northern Pwani Region in Tanzania. These findings will help farmers to understand the appropriate time for crop planting, as well as help other socio-economic activities that strongly depend on rainfall. 展开更多
关键词 inter-Annual Variability Rainfall Onset Crop Planting East Africa
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一起人炭疽事件引发的畜间流行病学调查
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作者 盛敏 阮武营 +2 位作者 马英英 颜新宇 赵胜杰 《中国动物检疫》 CAS 2024年第7期14-16,21,共4页
2023年7月26日,河南省某县卫健委通报马某等3人被确诊为皮肤炭疽,3人系亲属关系,从事牛羊养殖、屠宰、加工和销售工作。为调查疫病传染源、传播途径,降低畜间疫情发生和公共卫生风险,重点对病例关联的某养殖专业合作社马某肉牛养殖场、... 2023年7月26日,河南省某县卫健委通报马某等3人被确诊为皮肤炭疽,3人系亲属关系,从事牛羊养殖、屠宰、加工和销售工作。为调查疫病传染源、传播途径,降低畜间疫情发生和公共卫生风险,重点对病例关联的某养殖专业合作社马某肉牛养殖场、马某牛羊屠宰点和老马本地牛羊肉店开展了紧急流行病学调查。调查发现:病原随省外引进肉牛传入的可能性较小,马某等人通过宰杀带菌肉牛感染,并通过人员或生产资料将病原传入牛场的可能性较大,当前及近一段时间内当地发生人间和畜间炭疽的风险较低,但病原对当地牛羊养殖和公共卫生的潜在风险不容忽视。建议当地加大动物防疫相关政策宣传力度,普及炭疽等人兽共患病防控知识,切实做好炭疽等人兽共患病防控工作,防范疫情再次发生。 展开更多
关键词 炭疽 流行病学调查 畜间
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全球价值链嵌入、国内市场一体化与省际收入差距 被引量:2
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作者 蒋瑛 成东申 《中国地质大学学报(社会科学版)》 北大核心 2024年第1期128-142,共15页
从双重分工视角出发,将全球价值链嵌入与国内市场一体化纳入同一分析框架,采用省份两两配对面板数据,考察了全球价值链嵌入对省际收入差距的影响以及国内市场一体化的调节作用。研究发现:全球价值链嵌入扩大了省际收入差距,但是当国内... 从双重分工视角出发,将全球价值链嵌入与国内市场一体化纳入同一分析框架,采用省份两两配对面板数据,考察了全球价值链嵌入对省际收入差距的影响以及国内市场一体化的调节作用。研究发现:全球价值链嵌入扩大了省际收入差距,但是当国内市场一体化达到一定程度后,可以抑制全球价值链嵌入对省际收入差距扩大的负面影响。生产率差距是全球价值链嵌入作用于省际收入差距的重要渠道,而国内市场一体化则通过促进产业转移,缓解了全球价值链嵌入对省际收入差距扩大的负面影响。全球价值链嵌入扩大了中国东部省份与中西部省份之间的收入差距,而国内市场一体化可以倒U型调节由全球价值链嵌入所导致的中国东部省份与中西部省份之间的收入差距。构建国内价值链可以正向调节由全球价值链嵌入所导致的省际收入差距。本文基于双重分工视角为新时代中国统筹两个市场和两种资源,实现区域协调发展提供了重要启示。 展开更多
关键词 全球价值链 国内市场一体化 省际收入差距 国内价值链
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企业数字化转型促进了资本跨区域流动吗——基于异地并购视角的研究
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作者 刘锴 纳超洪 樊骁 《中南财经政法大学学报》 北大核心 2024年第4期3-16,共14页
加快资本跨区域流动对构建以国内大循环为主体、国内国际双循环相互促进的新发展格局具有重要的战略意义。本文以2008—2022年中国A股上市公司为样本,借助异地并购这一重要的资本跨区域流动形式,考察新发展格局下企业数字化转型对资本... 加快资本跨区域流动对构建以国内大循环为主体、国内国际双循环相互促进的新发展格局具有重要的战略意义。本文以2008—2022年中国A股上市公司为样本,借助异地并购这一重要的资本跨区域流动形式,考察新发展格局下企业数字化转型对资本跨区域流动的影响。研究发现:企业数字化转型通过降低并购交易成本和提高集团管控能力,有效地促进了异地并购决策,尤其对跨省并购决策的促进作用更显著。异质性分析结果表明,当并购企业所在地区市场化程度更高、税负水平更低、数字金融发展水平更高以及目标企业所在地区营商环境更好时,企业数字化转型对异地并购决策的促进作用更强;同时,这一促进作用在民营企业、非高新技术企业以及高管具有金融背景或海外背景的企业中更显著。本研究丰富了数字经济时代资本跨区域流动驱动因素的研究,从异地并购视角提供了企业数字化转型促进资本跨区域流动的微观证据。 展开更多
关键词 数字化转型 资本跨区域流动 异地并购 交易成本 集团管控能力
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