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青海电网新能源多尺度消纳规律及归因分析

电网与清洁能源 2024年第4期40卷 143-149页

作者：张帆张真鲜文军王艺霏王西超杨军国网青海省电力公司电力科学研究院青海西宁810008 国网青海省电力公司青海西宁810008

随着并网风、光装机的不断扩大,青海电网将面临日趋严峻的弃电问题。该文探索新能源弃电规律及影响因素,并提出大规模新能源消纳对策,对青海电网安全、高效运行具有重要的实践意义。首先,分析了青海电网近年来的运行状况,明确青海电网... 详细信息

随着并网风、光装机的不断扩大,青海电网将面临日趋严峻的弃电问题。该文探索新能源弃电规律及影响因素,并提出大规模新能源消纳对策,对青海电网安全、高效运行具有重要的实践意义。首先,分析了青海电网近年来的运行状况,明确青海电网多尺度弃电规律及其原因;其次,解析了多个典型日电网实际运行过程,阐明青海电网发生弃电的影响因素,并采用局部加权散点平滑回归(LOWESS)方法,构建了弃电率与新能源出力和水电之间的函数关系;最后,提出了提升青海省新能源消纳水平的措施。

关键词：新能源弃电规律弃电原因分析函数关系拟合新能源消纳措施

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孕早期孕妇抑郁的影响因素

中国民康医学 2024年第2期36卷 1-4,8页

作者：王希超李承瑞吴静于川王进刘佳佳齐建林空军特色医学中心航空心理研究室北京100142 解放军联勤保障部队第九六四医院精神心理科吉林长春130062

目的:分析孕早期孕妇抑郁的影响因素。方法:选取2019年3月至2021年10月于空军特色医学中心临床心理科建档的567名孕早期孕妇进行前瞻性研究,采用抑郁自评量表(SDS)评估孕妇抑郁状况,根据结果将其分为抑郁组和未抑郁组,统计两组基线资料... 详细信息

目的:分析孕早期孕妇抑郁的影响因素。方法:选取2019年3月至2021年10月于空军特色医学中心临床心理科建档的567名孕早期孕妇进行前瞻性研究,采用抑郁自评量表(SDS)评估孕妇抑郁状况,根据结果将其分为抑郁组和未抑郁组,统计两组基线资料,分析孕早期孕妇抑郁的影响因素。结果:567名孕早期孕妇中,59名SDS得分≥53分,孕早期抑郁发生率为10.41%(59/567);两组年龄、体质量指数、居住面积、孕周、职业、配偶年龄、配偶职业、父母同住、妊娠次数、分娩次数、不良孕产史、计划受孕、双方父母对怀孕态度、影响夫妻生活、分娩方式的选择比较,差异均无统计学意义(P>0.05);两组学历、吸烟史、饮酒史、抑郁病史、家庭月收入、居住地、围生儿死亡经历、妊娠期合并症、被家人照顾情况、恐惧怀孕过程、对孩子性别有期待、父母对孩子性别有期待、生活事件量表(LES)评分比较,差异均有统计学意义(P1,P<0.05)。结论:有饮酒史、有抑郁病史、对孩子性别有期待、父母对孩子性别有期待、LES评分≥20分均为孕早期孕妇抑郁的危险因素。

关键词：孕妇孕早期抑郁影响因素

Lateral root elongation in maize is related to auxin synthesis and transportation mediated by N metabolism under a mixed NO_(3)^(–) and NH_(4)^(+) supply

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Journal of Integrative Agriculture 2024年第3期23卷 1048-1060页

作者： Peng wang Lan Yang xichao Sun Wenjun Shi Rui Dong Yuanhua Wu Guohua Mi Key Laboratory of Tobacco Biology and Processing of Ministry of Agriculture and Rural Affairs Tobacco Research InstituteChineseAcademy of Agricultural SciencesQingdao 266101China Department of Plant Nutrition College of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China College of Resources Hunan Agricultural UniversityChangsha 410128China Agro-Environmental Protection Institute Ministry of Agriculture and Rural AffairsTianjin 300191China

A mixed nitrate (NO_(3)^(–)) and ammonium (NH_(4)^(+)) supply can promote root growth in maize (Zea mays),however,the changes in root morphology and the related physiological mechanism under different N forms are still ***,maize seedlings were grown hydroponically with three N supplied in three different forms (NO_(3)^(–)only,75/25 NO_(3)^(–)/NH_(4)^(+)and NH_(4)^(+)only).Compared with sole NO_(3)^(–)or NH_(4)^(+),the mixed N supply increased the total root length of maize but did not affect the number of axial *** main reason was the increased total lateral root length,while the average lateral root (LR) length in each axle was only slightly *** addition,the average LR density of 2nd whorl crown root under mixed N was also *** with sole nitrate,mixed N could improve the N metabolism of roots (such as the N influx rate,nitrate reductase (NR) and glutamine synthase (GS)enzyme activities and total amino content of the roots).Experiments with exogenously added NR and GS inhibitors suggested that the increase in the average LR length under mixed N was related to the process of N assimilation,and whether the NR mediated NO synthesis participates in this process needs further ***,an investigation of the changes in root-shoot ratio and carbon (C) concentration showed that C transportation from shoots to roots may not be the key factor in mediating lateral root elongation,and the changes in the sugar concentration in roots further proved this ***,the synthesis and transportation of auxin in axial roots may play a key role in lateral root elongation,in which the expression of ZmPIN1B and ZmPIN9 may be involved in this *** study preliminarily clarified the changes in root morphology and explored the possible physiological mechanism under a mixed N supply in maize,which may provide some theoretical basis for the cultivation of crop varieties with high N efficiency.

关键词： maize NO_(3)^(–)/NH_(4)^(+)ratio lateral root elongation N assimilation indole-3-acetic acid

Robust multi-sensor image matching based on normalized self-similarity region descriptor

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Chinese Journal of Aeronautics 2024年第1期37卷 271-286页

作者： Xuecong LIU xichao TENG Jing LUO Zhang LI Qifeng YU Yijie BIAN College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China High-Tech Institute Qingzhou 262500China

Multi-modal image matching is crucial in aerospace applications because it can fully exploit the complementary and valuable information contained in the amount and diversity of remote sensing ***,it remains a challenging task due to significant non-linear radiometric,geometric differences,and noise across different *** improve the performance of heterologous image matching,this paper proposes a normalized self-similarity region descriptor to extract consistent structural *** first construct the pointwise self-similarity region descriptor based on the Euclidean distance between adjacent image blocks to reflect the structural properties of multi-modal ***,a linear normalization approach is used to form Modality Independent Region Descriptor(MIRD),which can effectively distinguish structural features such as points,lines,corners,and flat between multi-modal *** further improve the matching accuracy,the included angle cosine similarity metric is adopted to exploit the directional vector information of multi-dimensional feature *** experimental results show that the proposed MIRD has better matching accuracy and robustness for various multi-modal image matching than the state-of-the-art *** can effectively extract consistent geometric structure features and suppress the influence of SAR speckle noise using non-local neighboring image blocks operation,effectively applied to various multi-modal image matching.

关键词： Remote sensing Multi-modal image matching Template matching Feature descriptor Similarity metric Synthetic Aperture Radar(SAR)

Advances in interspecific pregnancy

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Chinese Science Bulletin 2001年第21期46卷 1772-1778页

作者： xichao wang Bojie Dai Enkui Duan Dayuan Chen Chinese Acad Sci Inst Zool State Key Lab Reprod Biol Beijing 100080 Peoples R China

Interspecific pregnancy in which the conceptus and female carrying the pregnancy are of different species is a key step to interspecific cloning. Cloning endangered animals by interspecific pregnancy is such a highlight catching people’s eyes nowadays. In this article, the history of interspecific pregnancy, the methods for establishment of interspecific pregnancy, the corresponding theories, barriers and applied prospects are reviewed.

关键词： interspecific pregnancy cloning reproduction.

Interfamily pregnancy and expression of CD57, CD68 in deciduas between golden hamster and mouse

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Chinese Science Bulletin 2003年第18期48卷 1956-1961页

作者： xichao wang Bojie Dai Dayuan Chen Zelong Liu Weimin Liu Enkui Duan Chinese Acad Sci Inst Zool State Key Lab Reprod Biol Beijing 100080 Peoples R China

Pregnancy between different species is one of the key steps to interspecific somatic cell cloning. Although interspecific clone embryos have been constructed, they could not develop to birth after being transferred to recipi-ents. In order to clarify the mechanism of this phenomenon, interfamily pregnancy between golden hamste (Mesocricetus auratus) and mouse (Mus musculus) was studied. Co-culture results indicated that the adhesion ratios of golden hamster blastocysts on mouse uterine epithelia monolayer 12, 24, 48 and 72 h after co-culture were all significantly lower than those of mouse blastocysts. The outgrowth ratios of golden hamster blastocysts on mouse uterine epithelia monolayer 48, 72 h after co-culture were both significantly lower than those of mouse blastocysts (P < 0.01). Golden hamster抯 blastula could be implanted and develop to D 11 of pregnancy after being transferred to mouse uterus (the 7th day after embryo transfer). Compared to the transfer of mouse embryo to mouse uterus, the successful ratio of interfamily embryo transfer was lower and the bulk of fetus was smaller than that of intraspecific fetus. Compared to intraspecific preg-nancy of mouse, the remote decidual tissue of interfamily pregnancy on D8 is looser. At the same time, expressions of CD57 and CD 68 in remote deciduas were both higher than those in the secondary deciduas in both intraspecific and interfamily pregnancy. However, expressions of the two molecules in interfamily pregnancy were lower than those in intraspecific pregnancy. These results showed that interfam-ily pregnancy could be established between golden hamster and mouse. But the development of fetus in interfamily pregnancy was slower than that in intraspecific pregnancy. The expression difference of CD57 and CD68 indicates the difference of immunoreaction between interfamily and in-traspecific pregnancy, which may be one of the reasons lead-ing to interfamily pregnancy termination.

关键词： interfamily pregnancy golden hamster mouse CD57 CD68.

Rapid Phase Ambiguity Elimination Methods for DOA Estimator via Hybrid Massive MIMO Receive Array

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Chinese Journal of Electronics 2024年第1期33卷 175-184页

作者： xichao ZHAN Zhongwen SUN Feng SHU Yiwen CHEN Xin CHENG Yuanyuan WU Qi ZHANG Yifan LI Peng ZHANG School of Information and Communication Engineering Hainan University School of Electronic and Optical Engineering Nanjing University of Science and Technology

For a sub-connected hybrid multiple-input multiple-output(MIMO) receiver with K subarrays and N antennas, there exists a challenging problem of how to rapidly remove phase ambiguity in only single time-slot. A direction of arrival(DOA) estimator of maximizing received power(Max-RP) is proposed to find the maximum value of K-subarray output powers, where each subarray is in charge of one sector, and the center angle of the sector corresponding to the maximum output is the estimated true DOA. To make an enhancement on precision, Max-RP plus quadratic interpolation(Max-RP-QI) method is designed. In the proposed Max-RP-QI, a quadratic interpolation scheme is adopted to interpolate the three DOA values corresponding to the largest three receive powers of *** achieve the Cramer Rao lower bound, a Root-MUSIC plus Max-RP-QI scheme is developed. Simulation results show that the proposed three methods eliminate the phase ambiguity during one time-slot and also show low computational complexities. The proposed Root-MUSIC plus Max-RP-QI scheme can reach the Cramer Rao lower bound,and the proposed Max-RP and Max-RP-QI are still some performance losses 2–4 d B compared to the Cramer Rao lower bound.

关键词： Phased arrays Interpolation Wireless sensor networks Direction-of-arrival estimation Simulation Receiving antennas Massive MIMO

Glacial debris flow susceptibility mapping based on combined models in the Parlung Tsangpo Basin,China

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Journal of Mountain Science 2024年第4期21卷 1231-1245页

作者： ZHOU Yonghao HU Xiewen XI Chuanjie WEN Hong CAO xichao JIN Tao ZHOU Ruichen ZHANG Yu GONG Xueqiang Faculty of Geosciences and Engineering Southwest Jiaotong UniversityChengdu 611756China School of Architecture and Civil Engineering Xihua UniversityChengdu 610039China

Machine learning(ML)-based prediction models for mapping hazard(e.g.,landslide and debris flow)susceptibility have been widely developed in recent ***,in some specific areas,ML models have limited application because of the uncertainties in identifying negative *** Parlung Tsangpo Basin exemplifies a region prone to recurrent glacial debris flows(GDFs)and is characterized by a prominent landform featuring deep *** the limitations of the ML model,we developed and compared two combined statistical models(FA-WE and FA-IC)based on factor analysis(FA),weight of evidence(WE),and the information content(IC)*** final GDF susceptibility maps were generated by selecting 8 most important static factors and considering the influence of *** results show that the FA-IC model has the best *** areas with a very high susceptibility to GDFs are primarily located in the narrow valley section upstream,on both sides of the valley in the middle and downstream of the Parlung Tsangpo River,and in the narrow valley section of each *** areas encompass 86 gullies and are characterized as"narrow and steep".

关键词： Parlung Tsangpo Basin Glacial debris flow Factor analysis Susceptibility mapping Weight of evidence Information content method.

Strategic Thinking for Sustainable Development of Mining-Based Cities in China

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Chinese Journal of Population,Resources and Environment 2004年第3期2卷 60-63页

作者： Xie Shouxiang, Dai xichao & wang Yafen School of Management, China University of Mining & Technology, Xuzhou 221008, China School of Management China University of Mining and Technology Xuzhou 221008 China

Cities based on mining are distinctive from other cities in China. Their heavy dependence on minerals, a relatively undiversified industrial structure, seriously damaged ecological environment and the rather low degree of openness have all reduced their competitiveness, and severely constrained and hindered their sustainable development. In this paper the authors will study mining-based cities from the perspective of sustainable development, first by having a critical review of their features, and then by researching into strategic options to support their sustainable development.

关键词： mining-based cities growth strategy utilization of resources