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Analysis of the inflection points of height-diameter models
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作者 Tzeng Yih Lam Mark J.Ducey 《Forest Ecosystems》 SCIE CSCD 2024年第4期414-422,共9页
The inflection point is an important feature of sigmoidal height-diameter(H-D)models.It is often cited as one of the properties favoring sigmoidal model forms.However,there are very few studies analyzing the inflectio... The inflection point is an important feature of sigmoidal height-diameter(H-D)models.It is often cited as one of the properties favoring sigmoidal model forms.However,there are very few studies analyzing the inflection points of H-D models.The goals of this study were to theoretically and empirically examine the behaviors of inflection points of six common H-D models with a regional dataset.The six models were the Wykoff(WYK),Schumacher(SCH),Curtis(CUR),HossfeldⅣ(HOS),von Bertalanffy-Richards(VBR),and Gompertz(GPZ)models.The models were first fitted in their base forms with tree species as random effects and were then expanded to include functional traits and spatial distribution.The distributions of the estimated inflection points were similar between the two-parameter models WYK,SCH,and CUR,but were different between the threeparameter models HOS,VBR,and GPZ.GPZ produced some of the largest inflection points.HOS and VBR produced concave H-D curves without inflection points for 12.7%and 39.7%of the tree species.Evergreen species or decreasing shade tolerance resulted in larger inflection points.The trends in the estimated inflection points of HOS and VBR were entirely opposite across the landscape.Furthermore,HOS could produce concave H-D curves for portions of the landscape.Based on the studied behaviors,the choice between two-parameter models may not matter.We recommend comparing seve ral three-parameter model forms for consistency in estimated inflection points before deciding on one.Believing sigmoidal models to have inflection points does not necessarily mean that they will produce fitted curves with one.Our study highlights the need to integrate analysis of inflection points into modeling H-D relationships. 展开更多
关键词 CONCAVITY Forest inventory and analysis Generalized height-diameter models Growth functions Height-diameter functions Mixed-effects modeling points of inflection Species-specific models
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Quantitative determination of the critical points of Mott metal–insulator transition in strongly correlated systems
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作者 牛月坤 倪煜 +4 位作者 王建利 陈雷鸣 邢晔 宋筠 冯世平 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期647-652,共6页
Mottness is at the heart of the essential physics in a strongly correlated system as many novel quantum phenomena occur in the metallic phase near the Mott metal–insulator transition. We investigate the Mott transiti... Mottness is at the heart of the essential physics in a strongly correlated system as many novel quantum phenomena occur in the metallic phase near the Mott metal–insulator transition. We investigate the Mott transition in a Hubbard model by using the dynamical mean-field theory and introduce the local quantum state fidelity to depict the Mott metal–insulator transition. The local quantum state fidelity provides a convenient approach to determining the critical point of the Mott transition. Additionally, it presents a consistent description of the two distinct forms of the Mott transition points. 展开更多
关键词 critical point metal–insulator transition local quantum state fidelity strongly correlated system quasiparticle coherent weight
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Analysis of the Significance of Key Points of Patient Interventional Psychological Care and Pain Care
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作者 Xiaoping Dai Chu Luo Jiawei Dai 《Journal of Clinical and Nursing Research》 2024年第3期66-71,共6页
Interventional therapy has become increasingly popular in clinical practice due to advancements in medical technology.However,patients often experience psychological and physiological pressure due to its invasive natu... Interventional therapy has become increasingly popular in clinical practice due to advancements in medical technology.However,patients often experience psychological and physiological pressure due to its invasive nature.The management of patient discomfort and tension is crucial to ensure effective treatment.Psychological and pain management are essential components of interventional therapy,as they significantly impact patient recovery and prognosis.This article discussed the importance of interventional psychological and pain care for patients,starting with the development and spread of interventional therapy.The significance of providing high-quality nursing services to patients and improving their quality of life was also discussed. 展开更多
关键词 Interventional treatment Psychological nursing Pain care Key points Significance analysis
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K-1 Yongquan&Talahridaya points:A key to change the course of cardiopulmonary resuscitation(CPR)rescues
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作者 AdriánÁngel Inchauspe Gabriela Roxana Saidman 《Journal of Acute Disease》 2024年第6期208-215,I0001-I0004,共12页
Thirty-seven years have passed since the first K-1 resuscitation maneuver implementation next to both basic and advanced CPR failure and Prof.Inchauspe has consistently continued such unique research recovering impend... Thirty-seven years have passed since the first K-1 resuscitation maneuver implementation next to both basic and advanced CPR failure and Prof.Inchauspe has consistently continued such unique research recovering impending death situation victims in the most varied scenarios.After a dozen publications on the issue-mostly in World Journal of Critical Care Medicine and Hainan University Medical Editorial in China,the number of rescues increased to more than 195 cases.Having been contacted by experts in Ayurvedic medicine from India,the authors made a comparative analysis between said K-1 Yongquan and the Talahridaya points,and realized that not only are they located at the very same place for stimulation,but they are also integrated in the Reconciliation Vessel,a new Marvelous meridian discovered by Prof.Inchauspe within the Ancient Chinese classics.The following paper will show a statistical analysis made by Prof.Inchauspe and Dr.Saidman about the possible future impact that would result from the inclusion of the aforementioned maneuver in life support protocols. 展开更多
关键词 K-1 Yongquan Talahridaya Marma points Resuscitation complementary maneuver Impending death situations
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CLINICAL STUDY ON THE TREATMENT OF POST-STROKE DEPRESSION WITH ELECTROACUPUNCTURE OF “NIWAN BAZHEN” POINTS 被引量:6
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作者 蒋振亚 高李 +1 位作者 李常度 李金存 《World Journal of Acupuncture-Moxibustion》 2007年第1期11-16,共6页
Objective To observe the therapeutic effect of electroacupuncture (EA) of "Niwan Bazhen" points in the treatment of post-stroke depression. Methods A total of 66 post-stroke depression patients were randomized int... Objective To observe the therapeutic effect of electroacupuncture (EA) of "Niwan Bazhen" points in the treatment of post-stroke depression. Methods A total of 66 post-stroke depression patients were randomized into treatment group (EA+oral administration of Prozac-20, n =31 ) and control group (o- ral administration of Prozac-20, 20 mg/d, 28 days altogether, n =30). For patients of treatment group, EA (2/100 Hz, a tolerable stimulation strength) was applied to "Niwan Bazhen" points [Baihui (百会 GV20), etc. ] for 30 min, once daily, (except weekends) continuously for one month. Halmiton Rating Scale (HAMD) for Depression and Chinese Scale for Stroke (CSS) were used to evaluate the therapeutic effect. Results After the treatment, of the 30 and 31 cases in control and treatment groups, 4 and 6 were cured, 10 and 14 experienced marked improvement.in their symptoms, 6 and 7 had an improvement, 6 and 4 failed, with the cure+ markedly effective rates being 46.7% and 64.5% respectively. The therapeutic effect of treatment group was significantly superior to that of control group ( P〈0.05). The decreased values of both HAMD and C,,SS of treatment group were remarkably lower than those of control group (P〈0.01,0.05) . Conclusion EA of "Niwan Bazhen" points is an effective remedy for post-stroke depression. 展开更多
关键词 Post-stroke depression EA Niwon Bo.zhen points
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The Order of Approximation by Complex Rational Type Interpolating Operators at Fejer's Points 被引量:1
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作者 王子玉 朱长青 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第3期66-70,共5页
In this paper, supose Γ be a boundary of a Jordan domain D and Γ satisfied Альпер condition, the order that rational type interpolating operators at Fejer's points of f(z)∈C(Γ) converge to f(z) in the se... In this paper, supose Γ be a boundary of a Jordan domain D and Γ satisfied Альпер condition, the order that rational type interpolating operators at Fejer's points of f(z)∈C(Γ) converge to f(z) in the sense of uniformly convergence is obtained. 展开更多
关键词 rational type interpolation Fejer's points order of approximation Jordan domain
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The Order of Approximation by(0,1,…,q) Hermite-Fejer Interpolation Polynomials at Nearly Fejer's Points
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作者 沈燮昌 王鸿飞 朱长青 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第1期81-88,共8页
Suppose that the outer mapping function of domain D has its second continuous derivatives. In this paper, the order proximation by (0,1,…,q) Hermite-Fejer interpolating polynomials at nearly Fejer's points of fun... Suppose that the outer mapping function of domain D has its second continuous derivatives. In this paper, the order proximation by (0,1,…,q) Hermite-Fejer interpolating polynomials at nearly Fejer's points of function of class A(D) are presented. Moreover in general the order of approximation is sharp. 展开更多
关键词 Hermite-Fejer interpolating Fejer's point
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Material point method simulation of hydro-mechanical behaviour in twophase porous geomaterials: A state-of-the-art review 被引量:2
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作者 Xiangcou Zheng Shuying Wang +1 位作者 Feng Yang Junsheng Yang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2341-2350,共10页
The material point method(MPM)has been gaining increasing popularity as an appropriate approach to the solution of coupled hydro-mechanical problems involving large deformation.In this paper,we survey the current stat... The material point method(MPM)has been gaining increasing popularity as an appropriate approach to the solution of coupled hydro-mechanical problems involving large deformation.In this paper,we survey the current state-of-the-art in the MPM simulation of hydro-mechanical behaviour in two-phase porous geomaterials.The review covers the recent advances and developments in the MPM and their extensions to capture the coupled hydro-mechanical problems involving large deformations.The focus of this review is aiming at providing a clear picture of what has or has not been developed or implemented for simulating two-phase coupled large deformation problems,which will provide some direct reference for both practitioners and researchers. 展开更多
关键词 Coupled problems Hydro-mechanical behaviour Large deformation Material Point Method(MPM)
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On the Innovation,Design,Construction,and Experiments of OMEGA-Based SSPS Prototype:The Sun-Chasing Project 被引量:2
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作者 Baoyan Duan Yiqun Zhang +5 位作者 Guangda Chen Ze Zhao Jianwei Mi Xun Li Lin Yang Xi Li 《Engineering》 SCIE EI CAS CSCD 2024年第5期90-101,共12页
This study systematically introduces the development of the world’s first full-link and full-system ground demonstration and verification system for the OMEGA space solar power satellite(SSPS).First,the OMEGA 2.0 inn... This study systematically introduces the development of the world’s first full-link and full-system ground demonstration and verification system for the OMEGA space solar power satellite(SSPS).First,the OMEGA 2.0 innovation design was proposed.Second,field-coupling theoretical models of sunlight concentration,photoelectric conversion,and transmitting antennas were established,and a systematic optimization design method was proposed.Third,a beam waveform optimization methodology considering both a high beam collection efficiency and a circular stepped beam shape was proposed.Fourth,a control strategy was developed to control the condenser pointing toward the sun while maintaining the transmitting antenna toward the rectenna.Fifth,a high-efficiency heat radiator design method based on bionics and topology optimization was proposed.Sixth,a method for improving the rectenna array’s reception,rectification,and direct current(DC)power synthesis efficiencies is presented.Seventh,high-precision measurement technology for high-accuracy beam-pointing control was developed.Eighth,a smart mechanical structure was designed and developed.Finally,the developed SSPS ground demonstration and verification system has the capacity for sun tracking,a high concentration ratio,photoelectric conversion,microwave conversion and emission,microwave reception,and rectification,and thus satisfactory results were obtained. 展开更多
关键词 OMEGA-SSPS Full-link and full-system Beam collection efficiency Circular stepped beam shape Smart structure Field coupling theoretical model `Beam pointing control
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Research on the influence of flexible wheelset rotation effect on wheel rail contact force 被引量:1
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作者 Lixia Sun Yuanwu Cai +2 位作者 Di Cheng Xiaoyi Hu Chunyang Zhou 《Railway Sciences》 2024年第3期367-387,共21页
Purpose-Under the high-speed operating conditions,the effects of wheelset elastic deformation on the wheel rail dynamic forces will become more notable compared to the low-speed condition.In order to meet different an... Purpose-Under the high-speed operating conditions,the effects of wheelset elastic deformation on the wheel rail dynamic forces will become more notable compared to the low-speed condition.In order to meet different analysis requirements and selecting appropriate models to analyzing the wheel rail interaction,it is crucial to understand the influence of wheelset flexibility on the wheel-rail dynamics under different speeds and track excitations condition.Design/methodology/approach-The wheel rail contact points solving method and vehicle dynamics equations considering wheelset flexibility in the trajectory body coordinate system were investigated in this paper.As for the wheel-rail contact forces,which is a particular force element in vehicle multibody system,a method for calculating the Jacobian matrix of the wheel-rail contact force is proposed to better couple the wheel-rail contact force calculation with the vehicle dynamics response calculation.Based on the flexible wheelset modeling approach in this paper,two vehicle dynamic models considering the wheelset as both elastic and rigid bodies are established,two kinds of track excitations,namely normal measured track irregularities and short-wave irregularities are used,wheel-rail geometric contact characteristic and wheel-rail contact forces in both time and frequency domains are compared with the two models in order to study the influence of flexible wheelset rotation effect on wheel rail contact force.Findings-Under normal track irregularity excitations,the amplitudes of vertical,longitudinal and lateral forces computed by the flexible wheelset model are smaller than those of the rigid wheelset model,and the virtual penetration and equivalent contact patch are also slightly smaller.For the flexible wheelset model,the wheel rail longitudinal and lateral creepages will also decrease.The higher the vehicle speed,the larger the differences in wheel-rail forces computed by the flexible and rigid wheelset model.Under track short-wave irregularity excitations,the vertical force amplitude computed by the flexible wheelset is also smaller than that of the rigid wheelset.However,unlike the excitation case of measured track irregularity,under short-wave excitations,for the speed within the range of 200 to 350 km/h,the difference in the amplitude of the vertical force between the flexible and rigid wheelset models gradually decreases as the speed increase.This is partly due to the contribution of wheelset's elastic vibration under short-wave excitations.For low-frequency wheel-rail force analysis problems at speeds of 350 km/h and above,as well as high-frequency wheel-rail interaction analysis problems under various speed conditions,the flexible wheelset model will give results agrees better with the reality.Originality/value-This study provides reference for the modeling method of the flexible wheelset and the coupling method of wheel-rail contact force to the vehicle multibody dynamics system.Furthermore,by comparative research,the influence of wheelset flexibility and rotation on wheel-rail dynamic behavior are obtained,which is useful to the application scope of rigid and flexible wheelset models. 展开更多
关键词 Flexible wheelset Contact points calculation Rotational effects Elastic modes Wheel-rail force Papertype Researchpaper
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Blood-letting punctures at twelve Jing-Well points of the hand can treat cerebral ischemia in a similar manner to mannitol 被引量:17
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作者 Xuan Lu Zelin Chen +4 位作者 Yi Guo Liang Gao Liyuan Jiang Zhongzheng Li Jianqiao Fang 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第6期532-539,共8页
A rat model of middle cerebral artery permanent occlusion was established using the modified Longa method. Successfully established model animals were treated by blood-letting puncture at twelve Jing-Well points of th... A rat model of middle cerebral artery permanent occlusion was established using the modified Longa method. Successfully established model animals were treated by blood-letting puncture at twelve Jing-Well points of the hand, and/or by injecting mannitol into the caudal vein twice daily. Brain tissue was collected at 24, 48 and 72 hours after modeling, and blood was collected through the retinal vein before Evans blue was injected, approximately 1 hour prior to harvesting of brain tissue. Results showed that Evans blue leakage into brain tissue and serum nitric oxide synthase activity were significantly increased in model rats. Treatment with blood-letting punctures at twelve Jing-Well points of the hand and/or injection of mannitol into the caudal vein reduced the amount of Evans blue leakage into the brain tissue and serum nitric oxide synthase activity to varying degrees. There was no significant difference between single treatment and combined treatment. Experimental findings indicate that blood-letting punctures at twelve Jing-Well points of the hand can decrease blood-brain barrier permeability and serum nitric oxide synthase activity in rats following middle cerebral artery occlusion, and its effect is similar to that of mannitol injection alone and Jing-Well points plus mannitol injection. 展开更多
关键词 neural regeneration brain injury Jing-Well points of hand acupoint blood-letting MANNITOL middlecerebral artery occlusion cerebral ischemia cerebral infarction blood-brain barrier nitric oxidesynthase cerebral edema neuroprotection grants-supported paper neuroregeneration
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Does Biochar Addition Influence the Change Points of Soil Phosphorus Leaching? 被引量:11
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作者 ZHAO Xiao-rong LI Dan +1 位作者 KONG Juan LIN Qi-mei 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第3期499-506,共8页
Phosphorus change point indicating the threshold related to P leaching, largely depends on soil properties. Increasing data have shown that biochar addition can improve soil retention capacity of ions. However, we hav... Phosphorus change point indicating the threshold related to P leaching, largely depends on soil properties. Increasing data have shown that biochar addition can improve soil retention capacity of ions. However, we have known little about weather biochar amendment influence the change point of P leaching. In this study, two soils added with 0, 5, 10, 20, and 50 g biochar kg-1 were incubated at 25℃ for 14 d following adjusting the soil moisture to 50% water-holding capacity (WHC). The soils with different available P values were then obtained by adding a series of KH2PO4 solution (ranging from 0 to 600 mg P kg-1 soil), and subjecting to three cycles of drying and rewetting. The results showed that biochar addition significantly lifted the P change points in the tested soils, together with changes in soil pH, organic C, Olen-P and CaC12-P but little on exchangeable Ca and Mg, oxalate-extractable Fe and Al. The Olsen-P at the change points ranged from 48.65 to 185.07 mg kg-1 in the alluvial soil and 71.25 to 98.65 mg kg^-1 in the red soil, corresponding to CaCl2-P of 0.31-6.49 and 0.18-0.45 mg L~, respectively. The change points of the alluvial soil were readily changed by adding biochar compared with that of the red soil. The enhancement of change points was likely to be explained as the improvement of phosphate retention ability in the biochar-added soils. 展开更多
关键词 BIOCHAR SOIL PHOSPHORUS change point
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ON THE EXISTENCE OF ZERO POINTS OF A CONTINUOUS FUNCTION 被引量:7
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作者 J.M. SorianoDepartamento de Andlisis Matematico, Facultad de Matemdticas, Universidad de Sevilla, Aptdo. 1160, Sevilla 41080, Spain 《Acta Mathematica Scientia》 SCIE CSCD 2002年第2期171-177,共7页
A sufficient condition is given to assert that a continuous mapping between Rm and Rn has a zero. The constructive proof of the result is based upon continuation methods and supplies the existence of a path leading to... A sufficient condition is given to assert that a continuous mapping between Rm and Rn has a zero. The constructive proof of the result is based upon continuation methods and supplies the existence of a path leading to the zero point. 展开更多
关键词 Zero point continuation methods Banach fixed point theorem HOMOTOPY topological direct sum ISOMORPHISM k-contractive mapping
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Charging Pile Siting Recommendations via the Fusion of Points of Interest and Vehicle Trajectories 被引量:5
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作者 Yuan Kong Jianping Wu +1 位作者 Ming Xu Kezhen Hu 《China Communications》 SCIE CSCD 2017年第11期29-38,共10页
By mining of the requirements of lots of electric vehicle users for charging piles, this paper proposes the charging pile siting algorithm via the fusion of Points of Interest and vehicle trajectories. The proposed al... By mining of the requirements of lots of electric vehicle users for charging piles, this paper proposes the charging pile siting algorithm via the fusion of Points of Interest and vehicle trajectories. The proposed algorithm computes appropriate charging pile locations by: 1) mining user Points of Interest from social network; 2) mining parking sites of vehicle form GPS trajectories and 3) fusing the Points of Interest and parking sites together then clustering the fusions with our improved DBSCAN algorithm, whose clustering results indicates the final appropriate charging pile locations. Experimental results show that our proposed methods are more efficient than existing methods. 展开更多
关键词 charging pile siting recommendation points of Interest vehicle trajectories
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AN EXISTENCE THEOREM OF POSITIVE SOLUTIONS FOR ELASTIC BEAM EQUATION WITH BOTH FIXED END-POINTS 被引量:12
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作者 Jiang Xiufen Yao Qingliuof Math., Northwest Normal Univ., Lanzhou 730070. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2001年第3期237-240,共4页
By using the degree theory on cone an existence theorem of positive solution for a class of fourth-order two-point BVP's is obtained. This class of BVP's usually describes the deformation of the elastic beam w... By using the degree theory on cone an existence theorem of positive solution for a class of fourth-order two-point BVP's is obtained. This class of BVP's usually describes the deformation of the elastic beam with both fixed end-points. 展开更多
关键词 Elastic beam equation positive solution EXISTENCE fixed point theorem on cone.
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THREE KINDS OF DENTABILITIES IN BANACH SPACES AND THEIR APPLICATIONS
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作者 张子厚 周晶 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期445-454,共10页
In this paper,we study some dentabilities in Banach spaces which are closely related to the famous Radon-Nikodym property.We introduce the concepts of the weak^(*)-weak denting point and the weak^(*)-weak^(*)denting p... In this paper,we study some dentabilities in Banach spaces which are closely related to the famous Radon-Nikodym property.We introduce the concepts of the weak^(*)-weak denting point and the weak^(*)-weak^(*)denting point of a set.These are the generalizations of the weak^(*)denting point of a set in a dual Banach space.By use of the weak^(*)-weak denting point,we characterize the very smooth space,the point of weak^(*)-weak continuity,and the extreme point of a unit ball in a dual Banach space.Meanwhile,we also characterize an approximatively weak compact Chebyshev set in dual Banach spaces.Moreover,we define the nearly weak dentability in Banach spaces,which is a generalization of near dentability.We prove the necessary and sufficient conditions of the reflexivity by nearly weak dentability.We also obtain that nearly weak dentability is equivalent to both the approximatively weak compactness of Banach spaces and the w-strong proximinality of every closed convex subset of Banach spaces. 展开更多
关键词 weak^(*)-weak denting point nearly weak dentability very smooth space point of weak^(*)-weak continuity extreme point approximatively weak compactness w-strong proximinality REFLEXIVITY
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THERAPEUTIC EFFECT OF NEEDLE WARMING THROUGH MOXIBUSTION AT TWELVE SHU POINTS ON RHEUMATOID ARTHRITIS 被引量:3
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作者 李常度 蒋振亚 李应昆 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 1999年第1期22-26,共5页
Rheumatoid arthritis is a chronic andgeneral immunologic disease,mainlyinvolving the joints.Clinically,it is manifestedby morning ankylosis,arthroncus,jointdeformity and dysfunction.It falls into thecategory of arthra... Rheumatoid arthritis is a chronic andgeneral immunologic disease,mainlyinvolving the joints.Clinically,it is manifestedby morning ankylosis,arthroncus,jointdeformity and dysfunction.It falls into thecategory of arthralgia syndrome in traditionalChinese medicine(TCM).The authors havetreated 55 cases of rheumatoid arthritis byneedle warming through moxibustion 展开更多
关键词 Acupuncture therapy MOXIBUSTION Acupuncture points Adult Arthritis Rheumatoid Female Humans Male Middle Aged
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Prediction of collapse process and tipping points for mutualistic and competitive networks with k-core method
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作者 段东立 毕菲菲 +3 位作者 李思凡 吴成星 吕长春 蔡志强 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期173-180,共8页
Ecosystems generally have the self-adapting ability to resist various external pressures or disturbances,which is always called resilience.However,once the external disturbances exceed the tipping points of the system... Ecosystems generally have the self-adapting ability to resist various external pressures or disturbances,which is always called resilience.However,once the external disturbances exceed the tipping points of the system resilience,the consequences would be catastrophic,and eventually lead the ecosystem to complete collapse.We capture the collapse process of ecosystems represented by plant-pollinator networks with the k-core nested structural method,and find that a sufficiently weak interaction strength or a sufficiently large competition weight can cause the structure of the ecosystem to collapse from its smallest k-core towards its largest k-core.Then we give the tipping points of structure and dynamic collapse of the entire system from the one-dimensional dynamic function of the ecosystem.Our work provides an intuitive and precise description of the dynamic process of ecosystem collapse under multiple interactions,and provides theoretical insights into further avoiding the occurrence of ecosystem collapse. 展开更多
关键词 complex networks tipping points dimension reduction k-core
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Coexistence of Dirac and Weyl points in non-centrosymmetric semimetal NbIrTe_(4)
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作者 刘清馨 付阳 +4 位作者 丁鹏飞 马欢 郭朋杰 雷和畅 王善才 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期146-151,共6页
Using angle-resolved photoemission spectroscopy and density functional theory calculations methods,we investigate the electronic structures and topological properties of ternary tellurides NbIrTe_(4),a candidate for t... Using angle-resolved photoemission spectroscopy and density functional theory calculations methods,we investigate the electronic structures and topological properties of ternary tellurides NbIrTe_(4),a candidate for type-II Weyl semimetal.We demonstrate the presence of several Fermi arcs connecting their corresponding Weyl points on both termination surfaces of the topological material.Our analysis reveals the existence of Dirac points,in addition to Weyl points,giving both theoretical and experimental evidences of the coexistence of Dirac and Weyl points in a single material.These findings not only confirm NbIrTe_(4) as a unique topological semimetal but also open avenues for exploring novel electronic devices based on its coexisting Dirac and Weyl fermions. 展开更多
关键词 Fermi arc Weyl point Dirac point angle-resolved photoemission spectroscopy
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Finding of Gray Points on the Surface of the Sn-Fe Alloy Layer and Its Effects on the Corrosion Resistance of the Alloy Layer 被引量:4
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作者 王长钰 JiuguiHUANG +2 位作者 DeriZHOU DeyuLI KurachiMitsuo 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2003年第2期174-176,共3页
After removing tin coating of tinplates offered by some steel works, we discovered massive, highly disperse gray points outspreading along rolling direction on the surface of the alloy layer. Morphology of the alloy l... After removing tin coating of tinplates offered by some steel works, we discovered massive, highly disperse gray points outspreading along rolling direction on the surface of the alloy layer. Morphology of the alloy layer was observed by scanning electron microscope (SEM), and many cavities of the alloy layer were found out in the gray point. After analyzing the composition of the alloy layer, we found that content of Fe in the gray points was more than that in the normal alloy layer. Moreover, corrosion resistance of the alloy layer declines with increase of amount of gray points. In addition, the hot-humidity testing was carried out for some plates whose surface has many gray points. After 14 days, there were many rust points occurring in the edge of gray points and in the small gray points. The morphology of rust points was observed by atomic force microscope (AFM). The reason why rust points generated in the edge of gray points and in the small gray points was discussed. 展开更多
关键词 Sn-Fe alloy Gray point SEM AFM Corrosion resistance
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