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Iterative convergence theorems for maximal monotone operators and relatively nonexpansive mappings 被引量:5
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作者 WEI Li SU Yong-fu ZHOU Hai-yun 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第3期319-325,共7页
In this paper, some iterative schemes for approximating the common element of the set of zero points of maximal monotone operators and the set of fixed points of relatively nonexpansive mappings in a real uniformly sm... In this paper, some iterative schemes for approximating the common element of the set of zero points of maximal monotone operators and the set of fixed points of relatively nonexpansive mappings in a real uniformly smooth and uniformly convex Banach space are proposed. Some strong convergence theorems are obtained, to extend the previous work. 展开更多
关键词 maximal monotone operator relatively nonexpansive mapping strong convergence zero point fixed point
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Quantitative identification of relatively highlevel radioactive sandstone in the Upper Triassic Yanchang Formation of the Ordos Basin, China 被引量:2
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作者 Li Ya-Jun Zhang Xiao-Li Yan Yuan-Zi 《Applied Geophysics》 SCIE CSCD 2019年第3期314-320,395,396,共9页
Most relatively high-level radioactive sandstone(HRSS)reservoir has considerable oil(or gas)resource potential.HRSS is often wrongly identified due to its similar logging response characteristics as mudstone,which lea... Most relatively high-level radioactive sandstone(HRSS)reservoir has considerable oil(or gas)resource potential.HRSS is often wrongly identified due to its similar logging response characteristics as mudstone,which leads to the omission of effective reservoirs.In this paper,a quantitative identification method for HRSS is proposed after the analyzing of the response characteristics and relationship between spontaneous potential log and natural gamma-ray log in conventional sandstone and mudstone strata.Take the Upper Triassic Yanchang Formation in Ordos Basin as an example:the responses of spontaneous potential log and the responses of natural gamma-ray log are synchronized and positively correlated in conventional sandstone and mudstone strata,but they are not synchronized in HRSS.Quantitative identification of HRSS was realized based on this synchronization feature,and a"virtual compensation"of natural gamma-ray log was performed.At the same time,logging evaluation method about HRSS has been discussed.The final results shows that this identification method work effectively,and can reduce the misjudgment and omission of effective reservoirs. 展开更多
关键词 relatively high-level radioactive sandstone quantitative identification virtual compensation of radioactivity Ordos Basin Upper Triassic Yanchang Formation
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Comparison of Interruption in Relatively Formal and Informal Talk Show Programs
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作者 王晨宇 《海外英语》 2013年第13期251-252,共2页
Interruption,as a linguistic phenomenon,can be see everywhere.And talk show programs are common setting for interruptions.So in this thesis three questions are addressed as followed:What function does the interruption... Interruption,as a linguistic phenomenon,can be see everywhere.And talk show programs are common setting for interruptions.So in this thesis three questions are addressed as followed:What function does the interruption have in these two kinds of talk shows(relatively formal and informal) respectively;what are the similarities of relatively formal and informal talk show programs;what are the differences between relatively formal and informal talk shows. 展开更多
关键词 INTERRUPTION relatively FORMAL TALK SHOW PROGRAMS
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Strong convergence theorem for relatively nonexpansive mapping and inverse-strongly-monotone mapping in a Banach space
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作者 刘英 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第7期925-932,共8页
In this paper, we introduce an iterative sequence for finding a common element of the set of fixed points of a relatively nonexpansive mapping and the set of solutions of the variational inequality for an inverse-stro... In this paper, we introduce an iterative sequence for finding a common element of the set of fixed points of a relatively nonexpansive mapping and the set of solutions of the variational inequality for an inverse-strongly-monotone mapping in a Banach space. Then, we show that the sequence converges strongly to a common element of the two sets. Our results improve and extend the corresponding results reported by many others. 展开更多
关键词 relatively nonexpansive mapping generalized projection inverse-strongly-monotone variational inequality p-uniformly convex
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CONVERGENCE ANALYSIS FOR SYSTEM OF EQUILIBRIUM PROBLEMS AND LEFT BREGMAN STRONGLY RELATIVELY NONEXPANSIVE MAPPING
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作者 Yekini SHEHU 《Acta Mathematica Scientia》 SCIE CSCD 2014年第4期1081-1097,共17页
In this paper, we prove strong convergence theorems for approximation of a fixed point of a left Bregman strongly relatively nonexpansive mapping which is also a solution to a finite system of equilibrium problems in ... In this paper, we prove strong convergence theorems for approximation of a fixed point of a left Bregman strongly relatively nonexpansive mapping which is also a solution to a finite system of equilibrium problems in the framework of reflexive real Banach spaces. We also discuss the approximation of a common fixed point of a family of left Bregman strongly nonexpansive mappings which is also solution to a finite system of equilibrium problems in reflexive real Banach spaces. Our results complement many known recent results in the literature. 展开更多
关键词 left Bregman strongly relatively nonexpansive mapping left Bregman projection equilibrium problem Banach spaces
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New iterative schemes for strongly relatively nonexpansive mappings and maximal monotone operators
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作者 WEI Li SU Yong-fu ZHOU Hai-yun 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2010年第2期199-208,共10页
In this paper, some new iterative schemes for approximating the common element of the set of fixed points of strongly relatively nonexpansive mappings and the set of zero points of maximal monotone operators in a real... In this paper, some new iterative schemes for approximating the common element of the set of fixed points of strongly relatively nonexpansive mappings and the set of zero points of maximal monotone operators in a real uniformly smooth and uniformly convex Banach space are proposed. Some weak convergence theorems are obtained, which extend and complement some previous work. 展开更多
关键词 Strongly relatively nonexpansive mapping maximal monotone operator zero point fixed point weak convergence.
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Integral Sequences of Infinite Length Whose Terms Are Relatively Prime
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作者 Kazuyuki Hatada 《Advances in Pure Mathematics》 2013年第1期24-28,共5页
It is given in Weil and Rosenlicht ([1], p. 15) that (resp. 2) for all non-negative integers m and n with m≠n if c is any even (resp. odd) integer. In the present paper we generalize this. Our purpose is to give othe... It is given in Weil and Rosenlicht ([1], p. 15) that (resp. 2) for all non-negative integers m and n with m≠n if c is any even (resp. odd) integer. In the present paper we generalize this. Our purpose is to give other integral sequences such that G.C.D.(ym,yn)=1 for all positive integers m and n with m≠n. Roughly speaking we show the following 1) and 2). 1) There are infinitely many polynomial sequences such that G.C.D.(fm(a),fn(a))=1 for all positive integers m and n with with m≠n and infinitely many rational?integers a. 2) There are polynomial sequences such that G.C.D.(gm(a,b),gn(a,b))=1 for all positive integers m and n with m≠n and arbitrary (rational or odd) integers a and b with G.C.D.(a,b)=1. Main results of the present paper are Theorems 1 and 2, and Corollaries 3, 4 and 5. 展开更多
关键词 relatively PRIME INTEGRAL SEQUENCES of INFINITE LENGTH Sets of INFINITELY Many PRIME Numbers
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Structure of Relatively Accelerating Universe
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作者 Aloysius Sebastian 《International Journal of Astronomy and Astrophysics》 2014年第1期165-177,共13页
This article is about the structure of expanding universe. Here I am trying to create a structural model of universe according to my thoughts. Studies showthat universe is accelerating its rate of expansion. Here I am... This article is about the structure of expanding universe. Here I am trying to create a structural model of universe according to my thoughts. Studies showthat universe is accelerating its rate of expansion. Here I am trying to get some conclusions according to my thoughts. In my opinion, our universe is under a gravitational frame with all the matters in it. In this gravitational frame of universe we can consider our universe as a closed system and the empty space outside the frame as an open system. There are two possibilities we can find. One is relative motion of the objects inside the frame. By this way we can feel the universe is accelerating its expansion, but it is not. Another one is the vacuum energy absorption and negative pressure inside the frame. According to this thought, we can say that universe is accelerating and it can continue its motion at present conditions on it, even the force created by the big bang is decreasing. The other point is that, once the absorbed vacuum can create a negative pressure inside the frame, there is no need for the concept of dark energy in our universe [1]. According to this model, negative pressure inside the frame will be created by the absorbed vacuum from the space. So the existence of dark energy can be questioned. In this model, dark energy doesn't play any role in the expansion or rate of acceleration on the expansion of universe. So the dark energy doesn’t exist in this model. During the absorption of vacuum to the frame, it will increase the volume of the frame. It will create free spaces inside the frame to accommodate the vacuum inside the frame. The rest of the absorbed vacuum will move to the center of the frame by the action against gravity and the force created by the big bang. It will increase the density of the absorbed vacuum in the center and can create the negative pressure on the frame to pull it outside to the empty space. It will cause the acceleration on expansion of universe. These things are explained deeply in this article. And here it also explains the destiny of universe according to the frame and expansion of universe. 展开更多
关键词 STRUCTURE of UNIVERSE relatively Accelerating UNIVERSE DOES DARK Energy Exist GRAVITATIONAL FRAME of UNIVERSE
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Research on Model of Guiding Rural Residents' Relatively Centralized Residence——A Case Study of Chongqing City 被引量:1
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作者 SONG Fu-zhong ZHAO Hong-bin 《Asian Agricultural Research》 2011年第1期112-117,129,共7页
On the basis of expounding the status quo of rural residents' residence, the thesis notes that influenced by the weak foundation of rural economy, the characteristic of mountain landscape, smallholder consciousnes... On the basis of expounding the status quo of rural residents' residence, the thesis notes that influenced by the weak foundation of rural economy, the characteristic of mountain landscape, smallholder consciousness, shortage of capital and other factors, the rural residents in Chongqing City mainly live scattered. In addition to opportunities of the expansion and drive of city, rural market development, rural resources development, rural industrial development, and rural ecological migration, the model of urban development promotion, the model of market development drive, the model of land development drive, the model of rural industry construction and the model of resettlement and reconstruction are advocated in order to guide the rural residents to adopt relative centralized residence. The suggestions concerning guiding rural residents' relative centralized residence are put forward as follows: firstly, act according to circumstances and conduct scientific planning and design; secondly, propagate extensively and activate famers' willingness; thirdly, first experiment and exert the exemplary guide; fourthly, perfect policy and guarantee farmers' benefit; fifthly, strengthen leadership and decrease the risk of centralized residence; sixthly, boost gradually and realize moderate centralized residence. 展开更多
关键词 GUIDE Rural residents Relative centralized residence Chongqing City
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Mirror Frameworks for Relatively Lipschitz and Monotone-Like Variational Inequalities
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作者 Hui Zhang Yu-Hong Dai 《Journal of the Operations Research Society of China》 2025年第1期83-113,共31页
Nonconvex–nonconcave saddle-point optimization in machine learning has triggered lots of research for studying non-monotone variational inequalities(VIs).In this work,we introduce two mirror frameworks,called mirror ... Nonconvex–nonconcave saddle-point optimization in machine learning has triggered lots of research for studying non-monotone variational inequalities(VIs).In this work,we introduce two mirror frameworks,called mirror extragradient method and mirror extrapolation method,for approximating solutions to relatively Lipschitz and monotone-like VIs.The former covers the well-known Nemirovski’s mirror prox method and Nesterov’s dual extrapolation method,and the recently proposed Bregman extragradient method;all of them can be reformulated into a scheme that is very similar to the original form of extragradient method.The latter includes the operator extrapolation method and the Bregman extrapolation method as its special cases.The proposed mirror frameworks allow us to present a unified and improved convergence analysis for all these existing methods under relative Lipschitzness and monotone-like conditions that may be the currently weakest assumptions guaranteeing(sub)linear convergence. 展开更多
关键词 Extragradient Extrapolation Bregman distance SADDLE-POINT Mirror descent Relative Lipschitzness MONOTONE Variational inequality
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Research on the Impact of Rural E-commerce on Multi-dimensional Relative Poverty of Farmers
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作者 Wang Yanqi Chu Chu 《Journal of Northeast Agricultural University(English Edition)》 2025年第1期59-75,共17页
As China enters a new stage of agricultural modernization,understanding how rural e-commerce can address the multidimensional relative poverty of farmers is of significant research importance.This research utilized da... As China enters a new stage of agricultural modernization,understanding how rural e-commerce can address the multidimensional relative poverty of farmers is of significant research importance.This research utilized data from China Household Finance Survey(CHFS)and China Statistical Yearbook to construct a multi-dimensional relative poverty index system and an evaluation index system for rural e-commerce development.A fixed-effect model was employed to test the direct impact,and an intermediary-effect model was used to analyze the mechanism.The study found that rural e-commerce effectively alleviated multidimensional relative poverty among farmers,with varying effects across different dimensions.Notably,improving digital payment levels and non-agricultural employment were effective means by which rural e-commerce mitigated this poverty.However,the impact of rural e-commerce showed regional heterogeneity.Based on these findings,this research offered a series of countermeasures and suggestions. 展开更多
关键词 rural e-commerce relatively poor farmers digital payment non-agricultural employment
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Hypidone hydrochloride(YL-0919)ameliorates functional deficits after traumatic brain injury in mice by activating the sigma-1 receptor for antioxidation 被引量:2
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作者 Yafan Bai Hui Ma +5 位作者 Yue Zhang Jinfeng Li Xiaojuan Hou Yixin Yang Guyan Wang Yunfeng Li 《Neural Regeneration Research》 SCIE CAS 2025年第8期2325-2336,共12页
Traumatic brain injury involves complex pathophysiological mechanisms,among which oxidative stress significantly contributes to the occurrence of secondary injury.In this study,we evaluated hypidone hydrochloride(YL-0... Traumatic brain injury involves complex pathophysiological mechanisms,among which oxidative stress significantly contributes to the occurrence of secondary injury.In this study,we evaluated hypidone hydrochloride(YL-0919),a self-developed antidepressant with selective sigma-1 receptor agonist properties,and its associated mechanisms and targets in traumatic brain injury.Behavioral experiments to assess functional deficits were followed by assessment of neuronal damage through histological analyses and examination of blood-brain barrier permeability and brain edema.Next,we investigated the antioxidative effects of YL-0919 by assessing the levels of traditional markers of oxidative stress in vivo in mice and in vitro in HT22 cells.Finally,the targeted action of YL-0919 was verified by employing a sigma-1 receptor antagonist(BD-1047).Our findings demonstrated that YL-0919 markedly improved deficits in motor function and spatial cognition on day 3 post traumatic brain injury,while also decreasing neuronal mortality and reversing blood-brain barrier disruption and brain edema.Furthermore,YL-0919 effectively combated oxidative stress both in vivo and in vitro.The protective effects of YL-0919 were partially inhibited by BD-1047.These results indicated that YL-0919 relieved impairments in motor and spatial cognition by restraining oxidative stress,a neuroprotective effect that was partially reversed by the sigma-1 receptor antagonist BD-1047.YL-0919 may have potential as a new treatment for traumatic brain injury. 展开更多
关键词 antidepressant drug blood-brain barrier cognitive function hypidone hydrochloride(YL-0919) neurological function nuclear factor-erythroid 2 related factor 2 oxidative stress sigma-1 receptor superoxide dismutase traumatic brain injury
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Autophagy-targeting modulation to promote peripheral nerve regeneration 被引量:1
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作者 Yan Chen Hongxia Deng Nannan Zhang 《Neural Regeneration Research》 SCIE CAS 2025年第7期1864-1882,共19页
Nerve regeneration following traumatic peripheral nerve injuries and neuropathies is a complex process modulated by diverse factors and intricate molecular mechanisms.Past studies have focused on factors that stimulat... Nerve regeneration following traumatic peripheral nerve injuries and neuropathies is a complex process modulated by diverse factors and intricate molecular mechanisms.Past studies have focused on factors that stimulate axonal outgrowth and myelin regeneration.However,recent studies have highlighted the pivotal role of autophagy in peripheral nerve regeneration,particularly in the context of traumatic injuries.Consequently,autophagy-targeting modulation has emerged as a promising therapeutic approach to enhancing peripheral nerve regeneration.Our current understanding suggests that activating autophagy facilitates the rapid clearance of damaged axons and myelin sheaths,thereby enhancing neuronal survival and mitigating injury-induced oxidative stress and inflammation.These actions collectively contribute to creating a favorable microenvironment for structural and functional nerve regeneration.A range of autophagyinducing drugs and interventions have demonstrated beneficial effects in alleviating peripheral neuropathy and promoting nerve regeneration in preclinical models of traumatic peripheral nerve injuries.This review delves into the regulation of autophagy in cell types involved in peripheral nerve regeneration,summarizing the potential drugs and interventions that can be harnessed to promote this process.We hope that our review will offer novel insights and perspectives on the exploitation of autophagy pathways in the treatment of peripheral nerve injuries and neuropathies. 展开更多
关键词 AUTOPHAGY autophagy related genes Charcot–Marie–Tooth diseases diabetic peripheral neuropathy METFORMIN MYELINATION peripheral nerve injury Schwann cells sciatic nerve Wallerian degeneration
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Coupling and Spatial Disparities of Regional Economy and Ecosystem in High-Quality Town Development 被引量:2
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作者 Xinyi Ren Xiaowen Tan +2 位作者 Dan Luo Rongxin Lu Chien-Chi Chu 《Research in Ecology》 2025年第1期15-29,共15页
This study investigates the coordination between regional economic growth and ecological sustainability within the context of high-quality town economy development.To address the challenges of balancing economic expan... This study investigates the coordination between regional economic growth and ecological sustainability within the context of high-quality town economy development.To address the challenges of balancing economic expansion with environmental protection,a comprehensive evaluation index system is constructed,encompassing two key dimensions:regional economy and ecological environment.Using panel data from 2013 to 2022,the coupling coordination degree model is employed to quantify the interactions and synergy between these dimensions.Additionally,spatial econometric methods are applied to calculate both global and local Moran’s Index,revealing spatial clustering patterns,regional disparities,and heterogeneity.The relative development model further identifies critical factors influencing regional coordination,with a focus on the lagging development of basic infrastructure and public services.The findings demonstrate a positive temporal trend toward improved regional coordination and reduced development gaps,with a spatial pattern characterized by higher coupling degrees in eastern and central regions compared to western areas.Based on these results,this study proposes actionable strategies to enhance coordinated development,emphasizing ecological conservation,the establishment of green production and consumption systems,ecological restoration,and strengthened municipal collaboration.This revised abstract emphasizes the study’s purpose,methods,and key findings more clearly while maintaining a professional and concise tone.Finally,based on the above analysis results,the corresponding coordinated development suggestions of regional economy and ecological environment are given from the aspects of ecological environment protection measures,green production and consumption system construction,ecological environment restoration and municipal coordination. 展开更多
关键词 Regional Economies Ecological Environment Coupling Coordination Degree Spatiotemporal Distribution Characteristics Relative Development Model
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Factors Influencing the Efficacy of Chinese Medicinals 被引量:1
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作者 Qichao Liang Yun Jiang +1 位作者 Liguo Liang Hualong Liang 《Chinese Medicine and Natural Products》 2025年第2期73-85,共13页
This paper thoroughly explores the multifaceted factors influencing the efficacy of Chinese medicinals and categorizes them into three main groups:medicinal related factors,patient related factors,and practitioner rel... This paper thoroughly explores the multifaceted factors influencing the efficacy of Chinese medicinals and categorizes them into three main groups:medicinal related factors,patient related factors,and practitioner related factors.Regarding medicinal related factors,the place of origin,growing environment,harvesting time,storage conditions,quality control,dosage form selection,compatibility of medicinals,precise dosing,decoction methods,and administration routes all significantly impact efficacy.The place of origin determines the authenticity of medicinals,the growing environment affects their composition,harvesting time influences potency,improper storage leads to deterioration,quality control forms the foundation of efficacy,dosage forms and compatibility of medicinals affect absorption,dosing and decoction methods require precision,and administration routes should be tailored to individuals.Patient related factors include psychological state,individual differences,background,and disease condition.Psychological state affects treatment compliance,individual differences determine medicine responses,background influences patients’understanding of Chinese medicinals,and disease condition directly reflects efficacy.Practitioner related factors encompass theoretical knowledge,clinical experience,inherited practices,psychological state,and professional ethics.Theoretical knowledge guides medication use,clinical experience enhances efficacy,inherited practices influence prescribing styles,psychological state affects doctor–patient communication,and professional ethics ensure medical quality.These interrelated factors collectively influence the efficacy of Chinese medicinals,emphasizing the need for comprehensive consideration in clinical applications to achieve optimal therapeutic outcomes. 展开更多
关键词 Chinese medicinals efficacy of Chinese medicinals influencing factors medicinal related factors patient related factors practitioner related factors authentic medicinal materials
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Seasonal population trend and relative occurrence of pests and their natural enemies among cotton species and cultivars in India 被引量:1
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作者 NAGRARE V.S. NAIKWADI Bhausaheb +4 位作者 FAND Babasaheb B. NAIK V.Chinna Babu TENGURI Prabhulinga GOKTE‑NARKHEDKAR Nandini WAGHMARE V.N. 《Journal of Cotton Research》 2025年第2期178-192,共15页
Background Cotton crop is infested by numerous arthropod pests from sowing to harvesting,causing substantial direct and indirect yield losses.Knowledge of seasonal population trends and the relative occurrence of pest... Background Cotton crop is infested by numerous arthropod pests from sowing to harvesting,causing substantial direct and indirect yield losses.Knowledge of seasonal population trends and the relative occurrence of pests and their natural enemies is required to minimize the pest population and yield losses.In the current study,analysis of the seasonal population trend of pests and natural enemies and their relative occurrence on cultivars of three cotton species in Central India has been carried out.Results A higher number and diversity of sucking pests were observed during the vegetative cotton growth stage(60 days after sowing),declining as the crop matured.With the exception of cotton jassid(Amrasca biguttula biguttula Ishida),which caused significant crop damage mainly from August to September;populations of other sucking insects seldom reached economic threshold levels(ETL)throughout the studied period.The bollworm complex populations were minimal,except for the pink bollworm(Pectinophora gossypiella Saunders),which re-emerged as a menace to cotton crops during the cotton cropping season 2017–2018 due to resistance development against Bt-cotton.A reasonably good number of predatory arthropods,including coccinellids,lacewings,and spiders,were found actively preying on the arthropod pest complex of the cotton crop during the early vegetative growth stage.Linear regression indicates a significant relationship between green boll infestations and pink bollworm moths in pheromone traps.Multiple linear regression analyse showed mean weekly weather at one-or two-week lag periods had a significant impact on sucking pest population(cotton aphid,cotton jassid,cotton whitefly,and onion thrips)fluctuation.Gossypium hirsutum cultivars RCH 2 and DCH 32,and G.barbadense cultivar Suvin were found susceptible to cotton jassid and onion thrips.Phule Dhanvantary,an G.arboreum cotton cultivar,demonstrated the highest tolerance among all evaluated cultivars against all sucking pests.Conclusion These findings have important implications for pest management in cotton crops.Susceptible cultivars warrant more attention for plant protection measures,making them more input-intensive.The choice of appropriate cultivars can help minimize input costs,thereby increasing net returns for cotton farmers. 展开更多
关键词 COTTON PESTS Population trend Relative occurrence CULTIVARS Natural enemies
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Distribution,species richness,and relative importance of different plant life forms across drylands in China 被引量:1
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作者 Shuran Yao Weigang Hu +16 位作者 Mingfei Ji Abraham Allan Degen Qiajun Du Muhammad Adnan Akram Yuan Sun Ying Sun Yan Deng Longwei Dong Haiyang Gong Qingqing Hou Shubin Xie Xiaoting Wang Jinzhi Ran Bernhard Schmid Qinfeng Guo Karl J.Niklas Jianming Deng 《Plant Diversity》 2025年第2期273-281,共9页
Studies on plant diversity are usually based on the total number of species in a community.However,few studies have examined species richness(SR)of different plant life forms in a community along largescale environmen... Studies on plant diversity are usually based on the total number of species in a community.However,few studies have examined species richness(SR)of different plant life forms in a community along largescale environmental gradients.Particularly,the relative importance(RIV)of different plant life forms in a community and how they vary with environmental variables are still unclear.To fill these gaps,we determined plant diversity of ephemeral plants,annual herbs,perennial herbs,and woody plants from 187 sites across drylands in China.The SR patterns of herbaceous plants,especially perennial herbs,and their RIV in plant communities increased with increasing precipitation and soil nutrient content;however,the RIV of annual herbs was not altered along these gradients.The SR and RIV of ephemeral plants were affected mainly by precipitation seasonality.The SR of woody plants had a unimodal relationship with air temperature and exhibited the highest RIV and SR percentage in plant communities under the harshest environments.An obvious shift emerged in plant community composition,SR and their critical impact factors at 238.5 mm of mean annual precipitation(MAP).In mesic regions(>238.5 mm),herbs were the dominant species,and the SR displayed a relatively slow decreasing rate with increasing aridity,which was mediated mainly by MAP and soil nutrients.In arid regions(<238.5 mm),woody plants were the dominant species,and the SR displayed a relatively fast decreasing rate with increasing aridity,which was mediated mainly by climate variables,especially precipitation.Our findings highlight the importance of comparative life form studies in community structure and biodiversity,as their responses to gradients differed substantially on a large scale. 展开更多
关键词 DRYLANDS Environmental gradients Plant life forms Relative importance Species richness THRESHOLD
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Effective implementation of controlled blasting methodology during excavation of hard rock in the close proximity of earthen dam and tunnel 被引量:1
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作者 Prakash K.Palei Vijay K.Ghodake +5 位作者 S.Santhosh Kumar R.S.Gurjar Chaman Singh M.Meena Rizwan Ali R.S.Kankara 《Defence Technology(防务技术)》 2025年第6期306-316,共11页
The present technical paper outlines the details of the controlled blasting techniques used to optimize blasting pattern for excavation of hard rock near the Bhira Earthen Dam in Maharashtra,India.In this connection,a... The present technical paper outlines the details of the controlled blasting techniques used to optimize blasting pattern for excavation of hard rock near the Bhira Earthen Dam in Maharashtra,India.In this connection,a series of experimental blasts were conducted by adjusting various blast design parameters at project site.The safe charge weight per delay was kept between 0.125 and 0.375 kg.The outcomes of these experimental blasts were analyzed to recommend optimized blasting patterns and methods for the overall excavation process during actual blasting operations.Blast design parameters,including the maximum quantity of explosive per delay,hole depth,burden and spacing between holes were optimized by using a site-specific attenuation equation,taking into account the proximity of the dam and tunnel from the blasting area.Peak particle velocity(PPV)level of 10 mm/s and 50 mm/s respectively were adopted as the safe vibration level for ensuring safety of the Bhira Earthen Dam and the nearby tunnel from the adverse effects of blast vibrations by analyzing the dominant frequency of ground vibrations observed and also by reviewing various international standards.Frequency of the ground vibrations observed on the dam and tunnel from majority of the blasts was found to be more than 10 Hz and 50 Hz respectively.During the entire period of blasting,the blast vibrations were recorded to be far lower than the safe vibration level set for these structures.Maximum Vibration level of about 0.8 mm/s and 35 mm/s were observed on dam and tunnel respectively which are far lower than the safe vibration level adopted for these structures.Hence,the entire excavation work was completed successfully and safely,without endangering the safety of dam or tunnel. 展开更多
关键词 Controlled blasting Civil structure Ground vibration Attenuation relation
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Machine learning-based grayscale analyses for lithofacies identification of the Shahejie formation,Bohai Bay Basin,China 被引量:1
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作者 Yu-Fan Wang Shang Xu +4 位作者 Fang Hao Hui-Min Liu Qin-Hong Hu Ke-Lai Xi Dong Yang 《Petroleum Science》 2025年第1期42-54,共13页
It is of great significance to accurately and rapidly identify shale lithofacies in relation to the evaluation and prediction of sweet spots for shale oil and gas reservoirs.To address the problem of low resolution in... It is of great significance to accurately and rapidly identify shale lithofacies in relation to the evaluation and prediction of sweet spots for shale oil and gas reservoirs.To address the problem of low resolution in logging curves,this study establishes a grayscale-phase model based on high-resolution grayscale curves using clustering analysis algorithms for shale lithofacies identification,working with the Shahejie For-mation,Bohai Bay Basin,China.The grayscale phase is defined as the sum of absolute grayscale and relative amplitude as well as their features.The absolute grayscale is the absolute magnitude of the gray values and is utilized for evaluating the material composition(mineral composition+total organic carbon)of shale,while the relative amplitude is the difference between adjacent gray values and is used to identify the shale structure type.The research results show that the grayscale phase model can identify shale lithofacies well,and the accuracy and applicability of this model were verified by the fitting relationship between absolute grayscale and shale mineral composition,as well as corresponding re-lationships between relative amplitudes and laminae development in shales.Four lithofacies are iden-tified in the target layer of the study area:massive mixed shale,laminated mixed shale,massive calcareous shale and laminated calcareous shale.This method can not only effectively characterize the material composition of shale,but also numerically characterize the development degree of shale laminae,and solve the problem that difficult to identify millimeter-scale laminae based on logging curves,which can provide technical support for shale lithofacies identification,sweet spot evaluation and prediction of complex continental lacustrine basins. 展开更多
关键词 SHALE Machine learning Absolute grayscale Relative amplitude Grayscale phase model Lithofacies identification
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A model for predicting marine shale gas sweet spots based on relative sea-level changes and its application 被引量:1
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作者 Hongyan Wang Zhensheng Shi +2 位作者 Xi Yang Qun Zhao Changmin Guo 《Energy Geoscience》 2025年第2期142-154,共13页
Gas-bearing shales have become a major source of future natural gas production worldwide.It has become increasingly urgent to develop a reliable prediction model and corresponding workflow for identifying shale gas sw... Gas-bearing shales have become a major source of future natural gas production worldwide.It has become increasingly urgent to develop a reliable prediction model and corresponding workflow for identifying shale gas sweet spots.The formation of gas-bearing shales is closely linked to relative sealevel changes,providing an important approach to predicting sweet spots in the Wufeng-Longmaxi shale in the southern Sichuan Basin,China.Three types of marine shale gas sweet spots are identified in the shale based on their formation stages combined with relative sea-level changes:early,middle,and late transgression types.This study develops a prediction model and workflow for identifying shale gas sweet spots by analyzing relative sea-level changes and facies sequences.Predicting shale gas sweet spots in an explored block using this model and workflow can provide a valuable guide for well design and hydraulic fracturing,significantly enhancing the efficiency of shale gas exploration and development.Notably,the new prediction model and workflow can be utilized for the rapid evaluation of the potential for shale gas development in new shale gas blocks or those with low exploratory maturity. 展开更多
关键词 Shale gas Sweet spot Relative sea-level change Wufeng-longmaxi shale Southern sichuan basin
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