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Weak and Strong Convergence of Self Adaptive Inertial Subgradient Extragradient Algorithms for Solving Variational Inequality Problems
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作者 Yao Li Hongwei Liu Jiamin Lv 《Journal of Harbin Institute of Technology(New Series)》 CAS 2024年第2期38-49,共12页
Many solutions of variational inequalities have been proposed,among which the subgradient extragradient method has obvious advantages.Two different algorithms are given for solving variational inequality problem in th... Many solutions of variational inequalities have been proposed,among which the subgradient extragradient method has obvious advantages.Two different algorithms are given for solving variational inequality problem in this paper.The problem we study is defined in a real Hilbert space and has L-Lipschitz and pseudomonotone condition.Two new algorithms adopt inertial technology and non-monotonic step size rule,and their convergence can still be proved when the value of L is not given in advance.Finally,some numerical results are designed to demonstrate the computational efficiency of our two new algorithms. 展开更多
关键词 variational inequality inertial method non-monotonic step size rule Lipschitz continuity pseudomonotone mapping
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Research of Water Quality Analysis,Treatment and Reuse Technology for Rainwater on the North University Campus 被引量:1
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作者 Chen Shufang Shi Jingwei +1 位作者 Shao Yanjun Tu Chao 《Meteorological and Environmental Research》 CAS 2018年第1期62-65,共4页
The pollution situation of different underlying surface and the change rule of each water quality index were researched,on the basis of rainwater quality monitoring by different approaches in a university campus. The ... The pollution situation of different underlying surface and the change rule of each water quality index were researched,on the basis of rainwater quality monitoring by different approaches in a university campus. The results showed that due to some factors,such as the underlying surface material pollution,road materials,road surface pollution condition and surrounding atmospheric environment quality,the pollution of different underlying surface rainwater would be different. Main pollutants of rainwater runoff in the city campus area were such as COD,SS,NH;-N,TP,etc. Ultimately,along with the increase of accumulated rainfall,the pollutants tended to gradually decrease. The road rain pollution was more serious than roof runoff pollution and the early rain pollution was serious,but the late rain water quality was much better. According to the rainwater conditions,subsequent rainwater recycling technology and processing technology were determined as a way to alleviate the problem of water shortage and water pollution. 展开更多
关键词 NORTH Rainwater on campus Water quality analysis Variation rule Reuse technology
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Variation and Sexual Dimorphism of Body Size in the Plateau Brown Frog along an Altitudinal Gradient
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作者 Xueyun FENG Wei CHEN +1 位作者 Junhua HU Jianping JIANG 《Asian Herpetological Research》 SCIE CSCD 2015年第4期291-297,共7页
Variation in body size and sexual size dimorphism(SSD) can have important consequences for animal ecology, behavior, population dynamics and the evolution of life-history traits. Organisms are expected to be larger ... Variation in body size and sexual size dimorphism(SSD) can have important consequences for animal ecology, behavior, population dynamics and the evolution of life-history traits. Organisms are expected to be larger in colder climate(i.e., Bergmann's rule) and SSD varies with body size(i.e., Rensch's rule). However, the underlying mechanisms are still elusive. The plateau brown frog(Rana kukunoris), a medium-sized anuran species with femalebiased SSD, is endemic to the Qinghai-Tibetan Plateau(QTP). From 1797 m(Maoxiang'ping) to 3453 m(Heihe'qiao) in the eastern margin of the QTP, we surveyed 10 populations of R. kukunoris and collected phalanges and snout vent length(SVL) data for 258 adult individuals(199 males versus 59 females). Based on these data, we explored how body size and SSD varying along the altitudinal gradient and examined the corresponding effects of temperature. We found body size to be larger at higher altitude for males but not for females, with likely effects from the temperature on the variation in male body size. Sex differences in growth rates may be the main cause of the variation in SSD. Our results suggested that only males follow the Bergmann's rule and variation in SSD of R. kukunoris do not support the Rensch's rule and its inverse. Therefore, the variations of body size can be different between sexes and the applicability of both Bergmann's rule and Rensch's rule should depend on species and environment where they live. 展开更多
关键词 Altitudinal gradient Bergmann's rule body size variation Qinghai-Tibetan Plateau Rana kukunoris Rensch's rule sexual size dimorphism
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The Variation Rule and Anomaly Features of the Available Precipitation in the Growth Period of Crops in the Middle and Southern Part of Ningxia
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作者 ZHANG Zhi FENG Rui-ping +2 位作者 CHEN Yu-hua LIANG Xu SUN Yin-chuan 《Meteorological and Environmental Research》 2012年第8期49-52,共4页
[ Objective] The aim was to study the available precipitation and its abnormal characteristics during the growth period of crops in the mid- dle and southern part of Ningxia. [ Methed] Through Takahashi's evaporation... [ Objective] The aim was to study the available precipitation and its abnormal characteristics during the growth period of crops in the mid- dle and southern part of Ningxia. [ Methed] Through Takahashi's evaporation equation, linear trend analysis, Mann -Kendall, Lepage, wavelet analysis, the characteristics of available precipitation and its abnormal characteristics during its growth period in Ningxia were analyzed based on monthly precipitation (March- September), temperature, and NCAR/NCEP reanalysis data in 9 observation stations from 1961 to 2010. E Result l In recent 50 years, the available precipitation during the growth period of crops in central drought area and south hilly area varied a lot, more in the south and less in the north. The available precipitation in these two areas was reducing and varied a lot in different ages. The available precipitation was less in the middle drought region after 1970s and in the southern hilly region after 1990s and the available precipitation in middle drought area changed significantly. The available precipitation in the two areas appeared in July, August, and September, above 76% of general growth period, while that in March, April and May was 14% lower than that in growth period. No abrupt changes in central drought area and south hilly area. There were the periods of 5 -7 a and 2 -3 a oscillations in the middle drought region, 2 -3 a and 10 -12 a oscillations in the southern hilly region. There were negative anomaly field at 500hPa height in high-precipitation years between the Baikal and the China's northwestern, and there were positive anomaly field in low-precipitation years. [ Cenclusion] The study provided reference for the reasonable utilization of available water resources in cen- tral and south Ningxia. 展开更多
关键词 Middle and southern Ningxia Growth period of crops Available precipitation Variation rule Anomaly features China
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Harmony between man and nature:the base for the harmonious society
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作者 Lin Qing Chen Hongzhao Wang Qing Lin Yi 《Ecological Economy》 2007年第3期226-233,共8页
The harmony between man and nature is the base for the harmonious society. It is determined by the eco-ruleand eco-economic rule. Human being should not violate the eco-rule. However, human being can make eco-systemsu... The harmony between man and nature is the base for the harmonious society. It is determined by the eco-ruleand eco-economic rule. Human being should not violate the eco-rule. However, human being can make eco-systemsupply suit economic growth and its speed through systematical innovation and restriction of human economic activityand choice. Through technological innovation, efficiency satisfaction of unit resource can be increased; structure andfunction of eco-system can be perfected; supply capability of eco-system can be improved. To build the harmonioussociety, human should consider the reasonable distribution of limited resources from two sides. The first one is that theutilization of two functions of resource supply and pollution purification to nature should not exceed its special supplycapability formed under its special structure and function states, i.e. harmony between man and nature. The second sideis human being should think over the reasonable and effective distribution of limited resources in economic society, i.e.harmony between human beings and society. The reasonable economic activity of human being is the key to the harmo-nious development of man and nature. 展开更多
关键词 Man and nature Harmonious society Eco-economic rule
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Rule of Law and Harmony
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作者 DAIYUZHONG is member of Prosecutor Committee of Supreme People’s Procuratorate of P.R.China Director,Research Center for Criminal Jurisprudence of Renmin University of China. 《The Journal of Human Rights》 2007年第6期20-23,共4页
Ⅰ. Constructing a harmonious society is a major task of strategic importance put forward by the Chinese Party and government 1. A harmonious society is an inspiring goal the mankind has always pursued. Since ancient ... Ⅰ. Constructing a harmonious society is a major task of strategic importance put forward by the Chinese Party and government 1. A harmonious society is an inspiring goal the mankind has always pursued. Since ancient times, people have been pursuing social equality, stability and harmony. Some politicians, thinkers and scholars have made harmonious society as an ideal and a goal. Chinese great thinker and educator Confucius said: "Harmony is something to be cherished". Other Chinese philosophers such as Mo Zi and Meng Zi all advanced similar ideas. 展开更多
关键词 Rule of Law and harmony
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An Overview and Perspectives On Bidirectional Intelligence: Lmser Duality, Double IA Harmony,and Causal Computation 被引量:3
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作者 Lei Xu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第4期865-893,共29页
Advances on bidirectional intelligence are overviewed along three threads,with extensions and new perspectives.The first thread is about bidirectional learning architecture,exploring five dualities that enable Lmser s... Advances on bidirectional intelligence are overviewed along three threads,with extensions and new perspectives.The first thread is about bidirectional learning architecture,exploring five dualities that enable Lmser six cognitive functions and provide new perspectives on which a lot of extensions and particularlly flexible Lmser are proposed.Interestingly,either or two of these dualities actually takes an important role in recent models such as U-net,ResNet,and Dense Net.The second thread is about bidirectional learning principles unified by best yIng-yAng(IA)harmony in BYY system.After getting insights on deep bidirectional learning from a bird-viewing on existing typical learning principles from one or both of the inward and outward directions,maximum likelihood,variational principle,and several other learning principles are summarised as exemplars of the BYY learning,with new perspectives on advanced topics.The third thread further proceeds to deep bidirectional intelligence,driven by long term dynamics(LTD)for parameter learning and short term dynamics(STD)for image thinking and rational thinking in harmony.Image thinking deals with information flow of continuously valued arrays and especially image sequence,as if thinking was displayed in the real world,exemplified by the flow from inward encoding/cognition to outward reconstruction/transformation performed in Lmser learning and BYY learning.In contrast,rational thinking handles symbolic strings or discretely valued vectors,performing uncertainty reasoning and problem solving.In particular,a general thesis is proposed for bidirectional intelligence,featured by BYY intelligence potential theory(BYY-IPT)and nine essential dualities in architecture,fundamentals,and implementation,respectively.Then,problems of combinatorial solving and uncertainty reasoning are investigated from this BYY IPT perspective.First,variants and extensions are suggested for AlphaGoZero like searching tasks,such as traveling salesman problem(TSP)and attributed graph matching(AGM)that are turned into Go like problems with help of a feature enrichment technique.Second,reasoning activities are summarized under guidance of BYY IPT from the aspects of constraint satisfaction,uncertainty propagation,and path or tree searching.Particularly,causal potential theory is proposed for discovering causal direction,with two roads developed for its implementation. 展开更多
关键词 Autoencoder LMSER DUALITY outward attention associative recall concept formation imagining pattern transformation STD vs LTD RPCL skip connection feedback variational least redundancy Bayesian Ying Yang IA system best harmony best matching image THINKING rational THINKING INTELLIGENCE potential theory Alpha-TSP Alpha-AGM graph matching ME Player BYY Follower constraint satisfaction CAUSAL potential theory
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Chebyshev spectral variational integrator and applications 被引量:2
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作者 Zhonggui YI Baozeng YUE Mingle DENG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2020年第5期753-768,共16页
The Chebyshev spectral variational integrator(CSVI) is presented in this paper. Spectral methods have aroused great interest in approximating numerically a smooth problem for their attractive geometric convergence rat... The Chebyshev spectral variational integrator(CSVI) is presented in this paper. Spectral methods have aroused great interest in approximating numerically a smooth problem for their attractive geometric convergence rates. The geometric numerical methods are praised for their excellent long-time geometric structure-preserving properties.According to the generalized Galerkin framework, we combine two methods together to construct a variational integrator, which captures the merits of both methods. Since the interpolating points of the variational integrator are chosen as the Chebyshev points,the integration of Lagrangian can be approximated by the Clenshaw-Curtis quadrature rule, and the barycentric Lagrange interpolation is presented to substitute for the classic Lagrange interpolation in the approximation of configuration variables and the corresponding derivatives. The numerical float errors of the first-order spectral differentiation matrix can be alleviated by using a trigonometric identity especially when the number of Chebyshev points is large. Furthermore, the spectral variational integrator(SVI) constructed by the Gauss-Legendre quadrature rule and the multi-interval spectral method are carried out to compare with the CSVI, and the interesting kink phenomena for the Clenshaw-Curtis quadrature rule are discovered. The numerical results reveal that the CSVI has an advantage on the computing time over the whole progress and a higher accuracy than the SVI before the kink position. The effectiveness of the proposed method is demonstrated and verified perfectly through the numerical simulations for several classical mechanics examples and the orbital propagation for the planet systems and the Solar system. 展开更多
关键词 geometric numerical method spectral method variational integrator Clenshaw-Curtis quadrature rule barycentric Lagrange interpolation orbital propagation
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Recognizing Expression Variant and Occluded Face Images Based on Nested HMM and Fuzzy Rule Based Approach 被引量:1
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作者 Parvathi Ramalingam Shanthi Dhanushkodi 《Circuits and Systems》 2016年第6期983-994,共12页
The face recognition with expression and occlusion variation becomes the greatest challenge in biometric applications to recognize people. The proposed work concentrates on recognizing occlusion and seven kinds of exp... The face recognition with expression and occlusion variation becomes the greatest challenge in biometric applications to recognize people. The proposed work concentrates on recognizing occlusion and seven kinds of expression variations such as neutral, surprise, happy, sad, fear, disgust and angry. During enrollment process, principle component analysis (PCA) detects facial regions on the input image. The detected facial region is converted into fuzzy domain data to make decision during recognition process. The Haar wavelet transform extracts features from the detected facial regions. The Nested Hidden markov model is employed to train these features and each feature of face image is considered as states in a Markov chain to perform learning among the features. The maximum likelihood for the input image was estimated by using Baum Welch algorithm and these features were kept on database. During recognition process, the expression and occlusion varied face image is taken as the test image and maximum likelihood for test image is found by following same procedure done in enrollment process. The matching score between maximum likelihood of input image and test image is computed and it is utilized by fuzzy rule based method to decide whether the test image belongs to authorized or unauthorized. The proposed work was tested among several expression varied and occluded face images of JAFFE and AR datasets respectively. 展开更多
关键词 Face Recognition Fuzzy Rule Based Method Expression and Occlusion Variation Baum Welch Algorithm Nested Hidden Markov Model
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求解燃气轮机制造车间调度的混合和声搜索算法
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作者 李明辉 石宇强 +1 位作者 石小秋 李佳 《工业工程》 2024年第3期106-113,共8页
燃气轮机生产属于典型的离散型制造,其多品种小批量的生产特点给车间作业调度带来挑战,导致企业生产效率低下,不能满足产品交货期。因和声搜索算法结构简单易操作,常用于解决此类作业车间调度问题。然而传统和声搜索算法收敛速度较慢,... 燃气轮机生产属于典型的离散型制造,其多品种小批量的生产特点给车间作业调度带来挑战,导致企业生产效率低下,不能满足产品交货期。因和声搜索算法结构简单易操作,常用于解决此类作业车间调度问题。然而传统和声搜索算法收敛速度较慢,易陷入局部最优。本文构建以最小化最大完工时间为目标的燃气轮机制造车间调度数学模型,提出一种离散型改进多种群混合和声搜索算法进行求解。结合和声搜索算法与变邻域搜索算法的优点,采用基于工序的编码方式进行编码,在种群更新部分引入模拟退火的Metropolis接受准则,提高种群多样性;提出自适应的记忆库保留概率和音调调节率来调节参数,以提高算法的全局寻优能力;加入变邻域搜索以提高算法的收敛速度。通过性能测试及实例验证表明,相较于已有算法,所提算法具有更好的性能。 展开更多
关键词 燃气轮机制造车间调度 和声搜索算法(HS) 变邻域搜索(VNS) METROPOLIS准则
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基于“主客浑受”学说探析胰腺癌之发生发展及转移
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作者 廖冬颖 刘家宇 +6 位作者 王超然 张豪健 徐竞一 王晓群 孙彬栩 孔凡铭 贾英杰 《天津中医药》 CAS 2024年第7期845-848,共4页
胰腺癌素被冠有“癌王”之称,其起病隐匿,发病率及病死率在国内外均具有上升趋势。癌浊之毒损及胰腑,总以湿热、血瘀二者胶结,相因为患,脾气亏虚,气机壅遏,阴阳气不相顺接为要。“主客浑受”学说由清代温病学家薛生白提出,主要描述为湿... 胰腺癌素被冠有“癌王”之称,其起病隐匿,发病率及病死率在国内外均具有上升趋势。癌浊之毒损及胰腑,总以湿热、血瘀二者胶结,相因为患,脾气亏虚,气机壅遏,阴阳气不相顺接为要。“主客浑受”学说由清代温病学家薛生白提出,主要描述为湿热交作,瘀热互结,脉络受损,阴血耗伤之象,以通络祛瘀,清热化湿为治疗总则,辅以行气散结,益气扶正,培补营血。笔者通过临床观察及复习文献资料发现,“主客浑受”所阐释的病理状态与胰腺癌的发展、转移具有高度相似之处,文章试通过“主客浑受”学说浅析胰腺癌发展转移规律及治则治法。 展开更多
关键词 胰腺癌 主客浑受 治法治则
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青海省察尔汗盐湖区卤水中十二烷基吗啉的分布特征及变化规律
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作者 王金思 程怀德 +5 位作者 马海州 路淼 马亮 韩文华 马学海 吕翰羿 《环境污染与防治》 CAS CSCD 北大核心 2024年第6期890-895,共6页
青海省察尔汗盐湖区钾肥生产目前主要使用的反浮选药剂是十二烷基吗啉(DMP),但目前对于察尔汗盐湖区卤水中DMP的浓度及分布特征尚不清楚。采集了察尔汗盐湖区33个采样点的卤水样(其中部分为淡水样),采用甲基橙分光光度法对水样中DMP浓... 青海省察尔汗盐湖区钾肥生产目前主要使用的反浮选药剂是十二烷基吗啉(DMP),但目前对于察尔汗盐湖区卤水中DMP的浓度及分布特征尚不清楚。采集了察尔汗盐湖区33个采样点的卤水样(其中部分为淡水样),采用甲基橙分光光度法对水样中DMP浓度进行定量检测,分析湖区DMP浓度及分布特征。研究结果表明:(1)察尔汗盐湖区DMP浓度的空间分布呈现整体较低、部分地区出现高值的特征。(2)在湖区所采的不同类型水样中,DMP浓度呈现生产线卤水>盐田卤水>盐湖卤水>淡水≈采卤渠卤水的分布特征,质量浓度介于0.06~18.90 mg/L,平均值为2.16 mg/L。(3)卤水中DMP浓度受pH、电导率、Na^(+)、K^(+)、Mg^(2+)变化影响。 展开更多
关键词 察尔汗盐湖 浮选药剂 十二烷基吗啉 分布特征 变化规律
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全过程人民民主对西方民主的超越:“人民的统治”再阐释
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作者 戴激涛 《中共天津市委党校学报》 北大核心 2024年第3期26-37,共12页
针对西方民主面临的理论困境和实践难题,中国共产党人团结带领中国人民创造性地提出全过程人民民主重大理论,从理论逻辑、运行机理和实践进路明晰了作为民主本质的“人民的统治”核心要义,为如何实现民主有效运转设计了系统完备的制度... 针对西方民主面临的理论困境和实践难题,中国共产党人团结带领中国人民创造性地提出全过程人民民主重大理论,从理论逻辑、运行机理和实践进路明晰了作为民主本质的“人民的统治”核心要义,为如何实现民主有效运转设计了系统完备的制度体系。全过程人民民主坚持运用辩证唯物主义和历史唯物主义理解“人民”概念,始终把实现好、维护好、发展好最广大人民根本利益作为发展全过程人民民主的出发点和落脚点,是以人民为中心的和合型民主。全过程人民民主通过设计以确保人民当家作主的制度体系,始终坚持有事好商量、有事多商量,建立起高效协同的“全过程协商”机制确保人民始终“在场”,是以广泛协商为基本原则的参与型民主。全过程人民民主在实践主体层面始终坚持人民主体地位,确保最广泛的人民参与;在实践成效层面要求对国家权力进行全程制约和监督,以实现人民广泛权利和自由全面发展,是以“全过程”为鲜明特色的发展型民主。 展开更多
关键词 全过程人民民主 人民的统治 和合型民主 协商参与 发展型民主
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STRONGLY CONVERGENT INERTIAL FORWARD-BACKWARD-FORWARD ALGORITHM WITHOUT ON-LINE RULE FOR VARIATIONAL INEQUALITIES
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作者 姚永红 Abubakar ADAMU Yekini SHEHU 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期551-566,共16页
This paper studies a strongly convergent inertial forward-backward-forward algorithm for the variational inequality problem in Hilbert spaces.In our convergence analysis,we do not assume the on-line rule of the inerti... This paper studies a strongly convergent inertial forward-backward-forward algorithm for the variational inequality problem in Hilbert spaces.In our convergence analysis,we do not assume the on-line rule of the inertial parameters and the iterates,which have been assumed by several authors whenever a strongly convergent algorithm with an inertial extrapolation step is proposed for a variational inequality problem.Consequently,our proof arguments are different from what is obtainable in the relevant literature.Finally,we give numerical tests to confirm the theoretical analysis and show that our proposed algorithm is superior to related ones in the literature. 展开更多
关键词 forward-backward-forward algorithm inertial extrapolation variational inequality on-line rule
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乳腺癌复发恐惧变化规律及预测因子研究进展
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作者 冯颖 魏洪悦 王维宁 《全科护理》 2024年第1期112-115,共4页
综述乳腺癌复发恐惧的纵向变化规律和有关预测因子研究进展,指出低、中水平复发恐惧随时间逐渐下降,但具有个人差异性,高水平复发恐惧有相对独特的变化轨迹。年轻、低经济收入、情绪不乐观、低社会支持、更多的身体症状、家族史等是高... 综述乳腺癌复发恐惧的纵向变化规律和有关预测因子研究进展,指出低、中水平复发恐惧随时间逐渐下降,但具有个人差异性,高水平复发恐惧有相对独特的变化轨迹。年轻、低经济收入、情绪不乐观、低社会支持、更多的身体症状、家族史等是高水平复发恐惧的预测因子。目前国内仍缺少与乳腺癌复发恐惧的纵向及干预研究,未来可以加大在此方面的研究力度,争取对高危人群做到早识别、早干预。 展开更多
关键词 乳腺癌 癌症复发恐惧 变化规律 预测因子 综述
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知天与顺天:古代农谚中的生态哲学思想
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作者 王奋 刘铭 孙金荣 《农业考古》 北大核心 2024年第3期179-185,共7页
构建生态文明,需要借鉴中华农耕文明中的生态智慧。古代农谚是传统农业生产实践的直观反映,亦是中华农耕文明的重要载体,其中蕴涵着天人合一的生态哲学思想。它是古人知天畏命与顺天而为思想的有机融合,表现了古人在知晓、尊重客观生态... 构建生态文明,需要借鉴中华农耕文明中的生态智慧。古代农谚是传统农业生产实践的直观反映,亦是中华农耕文明的重要载体,其中蕴涵着天人合一的生态哲学思想。它是古人知天畏命与顺天而为思想的有机融合,表现了古人在知晓、尊重客观生态规律的基础上,充分发挥人的主观能动性,合理利用自然资源发展农业生产的生态智慧。研究中国古代农谚中天人合一的生态哲学思想,有助于重新审视人与自然生态的互动关系,对缓解当下的生态危机以及建设生态文明,具有一定的借鉴意义。 展开更多
关键词 古代农谚 天人合一 生态哲学 知天 顺天
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基于变异系数测度模型的农业经济与生态环境协调发展研究——以云南省为例
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作者 张远慧 《江西农业学报》 CAS 2024年第2期129-134,共6页
为对农业经济与生态环境协调发展水平进行有效测度,根据可持续发展理论,并遵循相关科学原则,提出农业经济与生态环境相协调的综合评价指标体系,在此基础上引入了变异系数测度方法,构建了农业经济与生态环境协调发展评价模型,并以云南省... 为对农业经济与生态环境协调发展水平进行有效测度,根据可持续发展理论,并遵循相关科学原则,提出农业经济与生态环境相协调的综合评价指标体系,在此基础上引入了变异系数测度方法,构建了农业经济与生态环境协调发展评价模型,并以云南省为例,对其农业经济与生态环境协调发展水平展开分析。结果显示:从整体来看,云南省农业经济和生态环境的发展综合协调指数呈递增趋势,从2012年的0.2699逐步增长到2022年的0.7371;在耦合协调度方面,云南省农业经济与生态环境的耦合协调度处于0.39~0.59之间,呈现波动上升的趋势,表现为由较弱失调向较弱协调转变,说明两系统的协调发展水平不断提高。 展开更多
关键词 变异系数 农业经济 生态环境 协调发展 评价指标
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中国新疆博斯腾湖现代碳库效应研究
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作者 杜丁丁 张成君 李志文 《湖泊科学》 EI CAS CSCD 北大核心 2024年第4期1279-1288,共10页
碳库效应存在影响了14 C测年的准确性,制约了沉积物在湖泊研究中的应用。本文研究位于典型西风环流带的新疆博斯腾湖现代碳库效应,结合同位素地球化学、水化学等方法,探讨了博斯腾湖碳库效应的影响机制。研究结果表明,博斯腾湖最大现代... 碳库效应存在影响了14 C测年的准确性,制约了沉积物在湖泊研究中的应用。本文研究位于典型西风环流带的新疆博斯腾湖现代碳库效应,结合同位素地球化学、水化学等方法,探讨了博斯腾湖碳库效应的影响机制。研究结果表明,博斯腾湖最大现代碳库年龄为3535年,最小为现代碳,集中在670~945年。而过去碳库效应集中在1033~2200年。深水区表现为碳库年龄较小且稳定;在入湖口碳库效应最大,富水生植物浅水区碳库效应最小。与过去碳库年龄相比较,现代碳库效应整体表现更为年轻。研究发现,博斯腾湖口受流域外源“死”碳影响,深水区受湖水与大气CO_(2)交换率差异影响,富水生植物浅水区可能受水生植物光合作用影响。此外,核爆效应也对博斯腾湖现代碳库效应产生了影响,可能导致最高约1000年的年代误差。利用深水区放射性碳比活度(pMC)平均值与大气碳比活度差值(~18%),得出深水区沉积物存在约846年现代碳库效应,再经核爆效应校正后得出博斯腾湖存在最高约1800年碳库效应。 展开更多
关键词 博斯腾湖 现代碳库效应 变化规律 影响因素
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人与自然和谐共生的法治回应与立法体现
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作者 李小强 《河南财经政法大学学报》 CSSCI 2024年第4期14-25,共12页
人与自然和谐共生的理论阐释需要以内涵解读为前提,以生成逻辑为基础。在全面依法治国的背景中,人与自然和谐共生的实现有赖于法治路径的选择。人与自然和谐共生的法治路径选择基于人与自然和谐共生的法治需求而形成,在传统法律部门中... 人与自然和谐共生的理论阐释需要以内涵解读为前提,以生成逻辑为基础。在全面依法治国的背景中,人与自然和谐共生的实现有赖于法治路径的选择。人与自然和谐共生的法治路径选择基于人与自然和谐共生的法治需求而形成,在传统法律部门中难以落实,在环境法律中的回应缺乏系统性、体系性和整全性。在人与自然和谐共生的法治回应的多重模式中,法律成典模式全面系统回应了人与自然和谐共生的理念。在环境法典的编纂中,应在理念、内容、实现路径等方面对人与自然和谐共生予以全面体现。 展开更多
关键词 人与自然和谐共生 法治回应 环境法典
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煤矿井下地磁定位的日变研究
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作者 黄康 孔维霄 +2 位作者 李卫强 史伊蕾 张丁尹 《地理空间信息》 2024年第11期83-86,共4页
近年来定位技术发展十分迅速,其中井下定位技术成为研究热点。在井下突发人员逃生、救援定位与导航等应急情况时,地磁定位可在无网络、无电时利用单兵PDA中内置的地磁基准图进行精准定位。首先分析了井下地磁定位的机理,并构建了井下地... 近年来定位技术发展十分迅速,其中井下定位技术成为研究热点。在井下突发人员逃生、救援定位与导航等应急情况时,地磁定位可在无网络、无电时利用单兵PDA中内置的地磁基准图进行精准定位。首先分析了井下地磁定位的机理,并构建了井下地磁定位框架;再针对井下地磁的扰动现象进行日变测量,并分析了其变化规律。多项实验结果表明,在无干扰条件下,井下地磁变化较小且呈周期性变化。 展开更多
关键词 井下地磁 日变规律 地磁定位 日变改正值 井下避险
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