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Genes for the high life: New genetic variants point to positive selection for high altitude hypoxia in Tibetans 被引量:2
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作者 Nina G.Jabionski 《Zoological Research》 CAS CSCD 2017年第3期117-117,共1页
People living on the high plateaus of the world have long fascinated biological anthropologists and geneticists because they live in "thin air" and epitomize an extreme of human biological adaptation.
关键词 HIGH for Genes for the high life New genetic variants point to positive selection for high altitude hypoxia in Tibetans in
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Research on Distance Judgement Method from Point to Line to Generate a Line 被引量:1
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作者 LU Di WANG Jian-xin +1 位作者 LIJta-feng TIAN Ye 《International Journal of Plant Engineering and Management》 2011年第3期134-138,共5页
Regarding the problem that the traditional straight-line generating has a low accuracy, we study straightline generating with the distance of point to line. We explore generating a line to approximate the ideal line a... Regarding the problem that the traditional straight-line generating has a low accuracy, we study straightline generating with the distance of point to line. We explore generating a line to approximate the ideal line and the issue is to pick out the pixel point of approximating the ideal line. The paper plays a significant scientific role in elucidating linear optimization norm and it lays a foundation for showing a straight line. The algorithm is valuable for computer graphics. 展开更多
关键词 straight line drawing distance of point to Line pixel point GRAPHICS
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Primary Study of Press the Point to Cure Some Acute Cases
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作者 Lu Jun(clinic 1458 Beijing) 《中国针灸》 CAS CSCD 北大核心 1995年第S2期294-294,共1页
PrimaryStudyofPressthePointtoCureSomeAcuteCases¥LuJun(clinic1458Beijing)Thetherapyofpressthepointispayedgrea... PrimaryStudyofPressthePointtoCureSomeAcuteCases¥LuJun(clinic1458Beijing)Thetherapyofpressthepointispayedgreatattentionbypeopl... 展开更多
关键词 Primary Study of Press the point to Cure Some Acute Cases
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Effects of variable properties on MHD heat and mass transfer flow near a stagnation point towards a stretching sheet in a porous medium with thermal radiation 被引量:4
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作者 A.M.Salem Rania Fathy 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第5期353-363,共11页
The effect of variable viscosity and thermal conductivity on steady magnetohydrodynamic(MHD) heat and mass transfer flow of viscous and incompressible fluid near a stagnation point towards a permeable stretching she... The effect of variable viscosity and thermal conductivity on steady magnetohydrodynamic(MHD) heat and mass transfer flow of viscous and incompressible fluid near a stagnation point towards a permeable stretching sheet embedded in a porous medium are presented,taking into account thermal radiation and internal heat genberation/absorbtion.The stretching velocity and the ambient fluid velocity are assumed to vary linearly with the distance from the stagnation point.The Rosseland approximation is used to describe the radiative heat flux in the energy equation.The governing fundamental equations are first transformed into a system of ordinary differential equations using a scaling group of transformations and are solved numerically by using the fourth-order Rung-Kutta method with the shooting technique.A comparison with previously published work has been carried out and the results are found to be in good agreement.The results are analyzed for the effect of different physical parameters,such as the variable viscosity and thermal conductivity,the ratio of free stream velocity to stretching velocity,the magnetic field,the porosity,the radiation and suction/injection on the flow,and the heat and mass transfer characteristics.The results indicate that the inclusion of variable viscosity and thermal conductivity into the fluids of light and medium molecular weight is able to change the boundary-layer behavior for all values of the velocity ratio parameter λ except for λ = 1.In addition,the imposition of fluid suction increases both the rate of heat and mass transfer,whereas fluid injection shows the opposite effect. 展开更多
关键词 variable viscosity variable thermal conductivity stagnation point
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Is the present cut-point to define type 2 diabetes appropriate in Latin-Americans? 被引量:1
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作者 Patricio López-Jaramillo Carlos Velandia-Carrillo +1 位作者 Diego Gómez-Arbeláez Martin Aldana-Campos 《World Journal of Diabetes》 SCIE CAS 2014年第6期747-755,共9页
The diagnosis of diabetes mellitus type 2(DM2) is based either on increased plasma glucose or Glycated hemoglobin levels. Since these measures are the only means for diagnosis of DM2, they must be well adapted to each... The diagnosis of diabetes mellitus type 2(DM2) is based either on increased plasma glucose or Glycated hemoglobin levels. Since these measures are the only means for diagnosis of DM2, they must be well adapted to each population according to their metabolic characteristics, given that these may vary in each population. The World Health Organization(WHO) determined the cut-points of plasma glucose levels for the diagnosis of DM2 by associating hyperglycemia with the risk of a specific microvascular complication-retinopathy. Cardiovascular diseases are however the principal causes of mortality in patients with DM2 and we reported that in the Colombo-Ecuadorian population impaired fasting glucose and impaired glucose tolerance are both riskmarkers for myocardial infarction. We propose that the current cut-points accepted by the WHO need to be revaluated in populations such as Latin America and that there should be lower cut points for glycaemia in this population, to reduce the prevalence of cardiovascular complications associated with DM2. 展开更多
关键词 Type 2 diabetes Cut-off points Cardiovascular diseases Plasma glucose Coronary disease
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Catgut Implantation at Baliao and Xingfu One Acupuncture Point to Treat Urinary Incontinence in Patients with Incomplete Spinal Cord Injury: Three Cases Report 被引量:1
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作者 Qingqing Li Laiming Yu +6 位作者 Hui Chen Ruzhi Zhang Qiuling Liu Maping Huang Dahui Zhang Shuqing Wu Jing Liu 《Open Journal of Urology》 2019年第8期115-118,共4页
Objective: To explore the effect of catgut implantation at Baliao and Xingfu One Acupuncture point for patients with urinary incontinence secondary to spinal cord injury (SCI). Methods: Three SCI patients received cat... Objective: To explore the effect of catgut implantation at Baliao and Xingfu One Acupuncture point for patients with urinary incontinence secondary to spinal cord injury (SCI). Methods: Three SCI patients received catgut embedding at Baliao and Xingfu One Acupuncture point. The data of intermittent catheterization (IC) volume, intermittent catheterization frequency and the amount of using urine pad (urethral condom) were corrected. Results: Compared to the baseline data, IC volume increased and the leakage volume decreased. Conclusions: Catgut Implantation at Baliao and Xingfu One Acupuncture point is effective for patients with urinary incontinence secondary to incomplete SCI. 展开更多
关键词 BALIAO and Xingfu ONE Acupuncture point CATGUT IMPLANTATION Spinal Cord Injury URINARY INCONTINENCE
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Unsteady Magnetohydrodynamic Boundary Layer Flow near the Stagnation Point towards a Shrinking Surface
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作者 Santosh Chaudhary Pradeep Kumar 《Journal of Applied Mathematics and Physics》 2015年第7期921-930,共10页
The unsteady two-dimensional, laminar flow of a viscous, incompressible, electrically conducting fluid towards a shrinking surface in the presence of a uniform transverse magnetic field is studied. Taking suitable sim... The unsteady two-dimensional, laminar flow of a viscous, incompressible, electrically conducting fluid towards a shrinking surface in the presence of a uniform transverse magnetic field is studied. Taking suitable similarity variables, the governing boundary layer equations are transformed to ordinary differential equations and solved numerically by a perturbation technique for a small magnetic parameter. The effects of various parameters such as unsteadiness parameter, velocity parameter, magnetic parameter, Prandtl number and Eckert number for velocity and temperature distributions along with local Skin friction coefficient and local Nusselt number have been discussed in detail through numerical and graphical representations. 展开更多
关键词 UNSTEADY Flow MAGNEtoHYDRODYNAMIC BOUNDARY Layer STAGNATION point SHRINKING SURFACE
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Catgut Implantation at Baliao and Xingfu One Acupuncture Point to Treat Dysdefecation in Patients with Incomplete Spinal Cord Injury: Three Cases Report
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作者 Qingqing Li Laiming Yu +6 位作者 Hui Chen Ruzhi Zhang Xinghua Yang Qiuling Liu Maping Huang Dahui Zhang Shuqing Wu 《Open Journal of Urology》 2020年第6期211-216,共6页
<strong>Objective:</strong> To probe into the effect of catgut implantation at Baliao and Xingfu One Acupuncture Point on dysdefecation in patients with incomplete spinal cord injury (SCI). <strong>M... <strong>Objective:</strong> To probe into the effect of catgut implantation at Baliao and Xingfu One Acupuncture Point on dysdefecation in patients with incomplete spinal cord injury (SCI). <strong>Methods:</strong> Three SCI patients voluntarily accepted catgut embedding at Baliao and Xingfu One Acupuncture point. Before and after treatment, they were filled out the self-rating scale of defecation, including the data of defecation frequency, total defecation time, defecation effort, fecal texture, fecal characteristics and fecal incontinence, etc. <strong>Results:</strong> Compared with the baseline data, constipation was improved and fecal incontinence was disappeared. <strong>Conclusions:</strong> Catgut implantation at Baliao and Xingfu One Acupuncture Point is effectual for patients with neurogenic dysporia secondary to incomplete SCI. 展开更多
关键词 BALIAO Xingfu One Acupuncture point Catgut Implantation Spinal Cord Injury Dysdefecation
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记忆的闪回与地标再生 伦敦 Centre Point Tower,英国
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作者 李佳琦(文/翻译) 《室内设计与装修》 2021年第S01期98-101,共4页
城市复兴的象征位于伦敦牛津街和托特纳姆法院路交界处的Centre Point Tower(以下简称Centre Point)建造于20世纪60年代,由著名建筑师理查德·塞弗特(Richard Seifert)设计。当时正值伦敦从一个灰色悲观的战后城市转变为明亮自信的... 城市复兴的象征位于伦敦牛津街和托特纳姆法院路交界处的Centre Point Tower(以下简称Centre Point)建造于20世纪60年代,由著名建筑师理查德·塞弗特(Richard Seifert)设计。当时正值伦敦从一个灰色悲观的战后城市转变为明亮自信的时尚之都。而Centre Point的设计和建成,恰恰用一种清晰的建筑语言,有形地描述了这座城市的复兴。 展开更多
关键词 塞弗 城市复兴 著名建筑师 toWER point 时尚之都 伦敦
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Automatic Extraction Method of 3D Feature Guidelines for Complex Cultural Relic Surfaces Based on Point Cloud 被引量:1
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作者 GENG Yuxin ZHONG Ruofei +1 位作者 HUANG Yuqin SUN Haili 《Journal of Geodesy and Geoinformation Science》 CSCD 2024年第1期16-41,共26页
Cultural relics line graphic serves as a crucial form of traditional artifact information documentation,which is a simple and intuitive product with low cost of displaying compared with 3D models.Dimensionality reduct... Cultural relics line graphic serves as a crucial form of traditional artifact information documentation,which is a simple and intuitive product with low cost of displaying compared with 3D models.Dimensionality reduction is undoubtedly necessary for line drawings.However,most existing methods for artifact drawing rely on the principles of orthographic projection that always cannot avoid angle occlusion and data overlapping while the surface of cultural relics is complex.Therefore,conformal mapping was introduced as a dimensionality reduction way to compensate for the limitation of orthographic projection.Based on the given criteria for assessing surface complexity,this paper proposed a three-dimensional feature guideline extraction method for complex cultural relic surfaces.A 2D and 3D combined factor that measured the importance of points on describing surface features,vertex weight,was designed.Then the selection threshold for feature guideline extraction was determined based on the differences between vertex weight and shape index distributions.The feasibility and stability were verified through experiments conducted on real cultural relic surface data.Results demonstrated the ability of the method to address the challenges associated with the automatic generation of line drawings for complex surfaces.The extraction method and the obtained results will be useful for line graphic drawing,displaying and propaganda of cultural relics. 展开更多
关键词 point cloud conformal parameterization vertex weight surface mesh cultural relics feature extraction
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Genetically modified pigs with CD163 point mutation are resistant to HP-PRRSV infection
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作者 Ying Liu Lin Yang +9 位作者 Hong-Yong Xiang Ming Niu Jia-Cheng Deng Xue-Yuan Li Wen-Jie Hao Hong-Sheng Ou-Yang Tong-Yu Liu Xiao-Chun Tang Da-Xin Pang Hong-Ming Yuan 《Zoological Research》 SCIE CSCD 2024年第4期833-844,共12页
Porcine reproductive and respiratory syndrome(PRRS)is a globally prevalent contagious disease caused by the positive-strand RNA PRRS virus(PRRSV),resulting in substantial economic losses in the swine industry.Modifyin... Porcine reproductive and respiratory syndrome(PRRS)is a globally prevalent contagious disease caused by the positive-strand RNA PRRS virus(PRRSV),resulting in substantial economic losses in the swine industry.Modifying the CD163 SRCR5 domain,either through deletion or substitution,can eff1ectively confer resistance to PRRSV infection in pigs.However,large fragment modifications in pigs inevitably raise concerns about potential adverse effects on growth performance.Reducing the impact of genetic modifications on normal physiological functions is a promising direction for developing PRRSV-resistant pigs.In the current study,we identified a specific functional amino acid in CD163 that influences PRRSV proliferation.Viral infection experiments conducted on Marc145 and PK-15CD163 cells illustrated that the mE535G or corresponding pE529G mutations markedly inhibited highly pathogenic PRRSV(HP-PRRSV)proliferation by preventing viral binding and entry.Furthermore,individual viral challenge tests revealed that pigs with the E529G mutation had viral loads two orders of magnitude lower than wild-type(WT)pigs,confirming effective resistance to HP-PRRSV.Examination of the physiological indicators and scavenger function of CD163 verified no significant differences between the WT and E529G pigs.These findings suggest that E529G pigs can be used for breeding PRRSV-resistant pigs,providing novel insights into controlling future PRRSV outbreaks. 展开更多
关键词 PRRSV CD163 point mutation E529G PIGS
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Emergent symmetry in quantum phase transition:From deconfined quantum critical point to gapless quantum spin liquid
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作者 Wen-Yuan Liu Shou-Shu Gong +1 位作者 Wei-Qiang Chen Zheng-Cheng Gu 《Science Bulletin》 SCIE EI CAS CSCD 2024年第2期190-196,共7页
The emergence of exotic quantum phenomena in frustrated magnets is rapidly driving the development of quantum many-body physics,raising fundamental questions on the nature of quantum phase transitions.Here we unveil t... The emergence of exotic quantum phenomena in frustrated magnets is rapidly driving the development of quantum many-body physics,raising fundamental questions on the nature of quantum phase transitions.Here we unveil the behaviour of emergent symmetry involving two extraordinarily representative phenomena,i.e.,the deconfined quantum critical point(DQCP)and the quantum spin liquid(QSL)state.Via large-scale tensor network simulations,we study a spatially anisotropic spin-1/2 square-lattice frustrated antiferromagnetic(AFM)model,namely the J1x-J1y-J2 model,which contains anisotropic nearestneighbor couplings J1x,J1y and the next nearest neighbor coupling J2.For small J1y/J1x,by tuning J2,a direct continuous transition between the AFM and valence bond solid phase is observed.With growing J1y/J1x,a gapless QSL phase gradually emerges between the AFM and VBS phases.We observe an emergent O(4)symmetry along the AFM–VBS transition line,which is consistent with the prediction of DQCP theory.Most surprisingly,we find that such an emergent O(4)symmetry holds for the whole QSL–VBS transition line as well.These findings reveal the intrinsic relationship between the QSL and DQCP from categorical symmetry point of view,and strongly constrain the quantum field theory description of the QSL phase.The phase diagram and critical exponents presented in this paper are of direct relevance to future experiments on frustrated magnets and cold atom systems. 展开更多
关键词 Tensor network Quantum phase transition Emergent symmetry QUANTUM spin liquid Deconfined quantum critical point ANISOTROPIC
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Triple points and phase transitions of D-dimensional dyonic Ad S black holes with quasitopological electromagnetism in Einstein–Gauss–Bonnet gravity
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作者 牟平辉 蒋青权 +1 位作者 何柯腱 李国平 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期272-287,共16页
By considering the negative cosmological constant Λ as a thermodynamic pressure, we study the thermodynamics and phase transitions of the D-dimensional dyonic Ad S black holes(BHs) with quasitopological electromagnet... By considering the negative cosmological constant Λ as a thermodynamic pressure, we study the thermodynamics and phase transitions of the D-dimensional dyonic Ad S black holes(BHs) with quasitopological electromagnetism in Einstein–Gauss–Bonnet(EGB) gravity. The results indicate that the small/large BH phase transition that is similar to the van der Waals(vdW) liquid/gas phase transition always exists for any spacetime dimensions. Interestingly, we then find that this BH system exhibits a more complex phase structure in 6-dimensional case that is missed in other dimensions.Specifically, it shows for D = 6 that we observed the small/intermediate/large BH phase transitions in a specific parameter region with the triple point naturally appeared. Moreover, when the magnetic charge turned off, we still observed the small/intermediate/large BH phase transitions and triple point only in 6-dimensional spacetime, which is consistent with the previous results. However, for the dyonic Ad S BHs with quasitopological electromagnetism in Einstein–Born–Infeld(EBI) gravity, the novel phase structure composed of two separate coexistence curves observed by Li et al. [Phys. Rev. D105 104048(2022)] disappeared in EGB gravity. This implies that this novel phase structure is closely related to gravity theories, and seems to have nothing to do with the effect of quasitopological electromagnetism. In addition, it is also true that the critical exponents calculated near the critical points possess identical values as mean field theory. Finally, we conclude that these findings shall provide some deep insights into the intriguing thermodynamic properties of the dyonic Ad S BHs with quasitopological electromagnetism in EGB gravity. 展开更多
关键词 AdS black hole phase transition triple point
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A Random Fusion of Mix 3D and Polar Mix to Improve Semantic Segmentation Performance in 3D Lidar Point Cloud
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作者 Bo Liu Li Feng Yufeng Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期845-862,共18页
This paper focuses on the effective utilization of data augmentation techniques for 3Dlidar point clouds to enhance the performance of neural network models.These point clouds,which represent spatial information throu... This paper focuses on the effective utilization of data augmentation techniques for 3Dlidar point clouds to enhance the performance of neural network models.These point clouds,which represent spatial information through a collection of 3D coordinates,have found wide-ranging applications.Data augmentation has emerged as a potent solution to the challenges posed by limited labeled data and the need to enhance model generalization capabilities.Much of the existing research is devoted to crafting novel data augmentation methods specifically for 3D lidar point clouds.However,there has been a lack of focus on making the most of the numerous existing augmentation techniques.Addressing this deficiency,this research investigates the possibility of combining two fundamental data augmentation strategies.The paper introduces PolarMix andMix3D,two commonly employed augmentation techniques,and presents a new approach,named RandomFusion.Instead of using a fixed or predetermined combination of augmentation methods,RandomFusion randomly chooses one method from a pool of options for each instance or sample.This innovative data augmentation technique randomly augments each point in the point cloud with either PolarMix or Mix3D.The crux of this strategy is the random choice between PolarMix and Mix3Dfor the augmentation of each point within the point cloud data set.The results of the experiments conducted validate the efficacy of the RandomFusion strategy in enhancing the performance of neural network models for 3D lidar point cloud semantic segmentation tasks.This is achieved without compromising computational efficiency.By examining the potential of merging different augmentation techniques,the research contributes significantly to a more comprehensive understanding of how to utilize existing augmentation methods for 3D lidar point clouds.RandomFusion data augmentation technique offers a simple yet effective method to leverage the diversity of augmentation techniques and boost the robustness of models.The insights gained from this research can pave the way for future work aimed at developing more advanced and efficient data augmentation strategies for 3D lidar point cloud analysis. 展开更多
关键词 3D lidar point cloud data augmentation RandomFusion semantic segmentation
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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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Multi-Objective Optimization Algorithm for Grouping Decision Variables Based on Extreme Point Pareto Frontier
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作者 JunWang Linxi Zhang +4 位作者 Hao Zhang Funan Peng Mohammed A.El-Meligy Mohamed Sharaf Qiang Fu 《Computers, Materials & Continua》 SCIE EI 2024年第4期1281-1299,共19页
The existing algorithms for solving multi-objective optimization problems fall into three main categories:Decomposition-based,dominance-based,and indicator-based.Traditional multi-objective optimization problemsmainly... The existing algorithms for solving multi-objective optimization problems fall into three main categories:Decomposition-based,dominance-based,and indicator-based.Traditional multi-objective optimization problemsmainly focus on objectives,treating decision variables as a total variable to solve the problem without consideringthe critical role of decision variables in objective optimization.As seen,a variety of decision variable groupingalgorithms have been proposed.However,these algorithms are relatively broad for the changes of most decisionvariables in the evolution process and are time-consuming in the process of finding the Pareto frontier.To solvethese problems,a multi-objective optimization algorithm for grouping decision variables based on extreme pointPareto frontier(MOEA-DV/EPF)is proposed.This algorithm adopts a preprocessing rule to solve the Paretooptimal solution set of extreme points generated by simultaneous evolution in various target directions,obtainsthe basic Pareto front surface to determine the convergence effect,and analyzes the convergence and distributioneffects of decision variables.In the later stages of algorithm optimization,different mutation strategies are adoptedaccording to the nature of the decision variables to speed up the rate of evolution to obtain excellent individuals,thusenhancing the performance of the algorithm.Evaluation validation of the test functions shows that this algorithmcan solve the multi-objective optimization problem more efficiently. 展开更多
关键词 Multi-objective evolutionary optimization algorithm decision variables grouping extreme point pareto frontier
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Efficacy comparison of multipoint and single point scanning panretinal laser photocoagulation in non-proliferative diabetic retinopathy treatment
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作者 Yang-Zhou Zhang Hua Gong +2 位作者 Juan Yang Ji-Pu Bu Hui-Ling Yang 《World Journal of Diabetes》 SCIE 2024年第8期1734-1741,共8页
BACKGROUND Non-proliferative diabetic retinopathy(NPDR)poses a significant challenge in diabetes management due to its microvascular changes in the retina.Laser photocoagulation,a conventional therapy,aims to mitigate... BACKGROUND Non-proliferative diabetic retinopathy(NPDR)poses a significant challenge in diabetes management due to its microvascular changes in the retina.Laser photocoagulation,a conventional therapy,aims to mitigate the risk of progressing to proliferative diabetic retinopathy(PDR).AIM To compare the efficacy and safety of multi-spot vs single-spot scanning panretinal laser photocoagulation in NPDR patients.METHODS Forty-nine NPDR patients(86 eyes)treated between September 2020 and July 2022 were included.They were randomly allocated into single-spot(n=23,40 eyes)and multi-spot(n=26,46 eyes)groups.Treatment outcomes,including bestcorrected visual acuity(BCVA),central macular thickness(CMT),and mean threshold sensitivity,were assessed at predetermined intervals over 12 months.Adverse reactions were also recorded.RESULTS Energy levels did not significantly differ between groups(P>0.05),but the multi-spot group exhibited lower energy density(P<0.05).BCVA and CMT improvements were noted in the multi-spot group at one-month posttreatment(P<0.05).Adverse reaction incidence was similar between groups(P>0.05).CONCLUSION While energy intensity and safety were comparable between modalities,multi-spot scanning demonstrated lower energy density and showed superior short-term improvements in BCVA and CMT for NPDR patients,with reduced laser-induced damage. 展开更多
关键词 Panretinal laser photocoagulation Non-proliferative diabetic retinopathy Efficacy comparison Multipoint Single point Treatment assessment
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Probabilistic Global Maximum Power Point Tracking Algorithm for Continuously Varying Partial Shading Conditions on Autonomous PV Systems
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作者 Kha Bao Khanh Cao Vincent Boitier 《Energy and Power Engineering》 2024年第1期21-42,共22页
A photovoltaic (PV) string with multiple modules with bypass diodes frequently deployed on a variety of autonomous PV systems may present multiple power peaks under uneven shading. For optimal solar harvesting, there ... A photovoltaic (PV) string with multiple modules with bypass diodes frequently deployed on a variety of autonomous PV systems may present multiple power peaks under uneven shading. For optimal solar harvesting, there is a need for a control schema to force the PV string to operate at global maximum power point (GMPP). While a lot of tracking methods have been proposed in the literature, they are usually complex and do not fully take advantage of the available characteristics of the PV array. This work highlights how the voltage at operating point and the forward voltage of the bypass diode are considered to design a global maximum power point tracking (GMPPT) algorithm with a very limited global search phase called Fast GMPPT. This algorithm successfully tracks GMPP between 94% and 98% of the time under a theoretical evaluation. It is then compared against Perturb and Observe, Deterministic Particle Swarm Optimization, and Grey Wolf Optimization under a sequence of irradiance steps as well as a power-over-voltage characteristics profile that mimics the electrical characteristics of a PV string under varying partial shading conditions. Overall, the simulation with the sequence of irradiance steps shows that while Fast GMPPT does not have the best convergence time, it has an excellent convergence rate as well as causes the least amount of power loss during the global search phase. Experimental test under varying partial shading conditions shows that while the GMPPT proposal is simple and lightweight, it is very performant under a wide range of dynamically varying partial shading conditions and boasts the best energy efficiency (94.74%) out of the 4 tested algorithms. 展开更多
关键词 PHOtoVOLTAIC PV Global Maximum Power point Tracking GMPPT Fast Varying Partial Shading Conditions Autonomous PV Systems GMPPT Review
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On a Heuristic Point of View about the Generalization of Curie Law to Cosmic Higgs Fields with the Casimir Effect
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作者 Hung-Te Henry Su Po-Han Lee 《Journal of Applied Mathematics and Physics》 2024年第9期3135-3147,共13页
Condensed state physics demonstrates that the Curie temperature is the point at which spontaneous magnetization drops to zero, marking the critical transition where ferromagnetic or ferrimagnetic materials transform i... Condensed state physics demonstrates that the Curie temperature is the point at which spontaneous magnetization drops to zero, marking the critical transition where ferromagnetic or ferrimagnetic materials transform into paramagnetic substances. Below the Curie temperature, a material remains ferromagnetic;above it, the material becomes paramagnetic, with its magnetic field easily influenced by external magnetic fileds. For example, the Curie temperature of iron (Fe) is 1043 K, while that of neodymium magnets ranges from 583 to 673 K. From both physics and mathematics perspectives, examining the temperature properties of materials is essential, as it provides valuable insights into their electromagnetic and thermodynamic behaviors. This paper makes a bold assumption and, for the first time, carefully verifies the existence of a Casimir temperature at 0.00206 K under conditions of one-atomic spacing. 展开更多
关键词 Curie Temperature Curie point Casimir Temperature Critical point Fields Materials One-Atomic Spacing
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Qualitative Properties of Equilibrium Point in a Discrete Predator-Prey Model
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作者 Weijie Lin Minhong Yang +2 位作者 Chenhao Sun Kaiwen Guan Xiaoliang Zhou 《Journal of Applied Mathematics and Physics》 2024年第8期2920-2927,共8页
In this paper, the dynamic properties of a discrete predator-prey model are discussed. The properties of non-hyperbolic fixed points and hyperbolic fixed points of the model are analyzed. First, by using the classic S... In this paper, the dynamic properties of a discrete predator-prey model are discussed. The properties of non-hyperbolic fixed points and hyperbolic fixed points of the model are analyzed. First, by using the classic Shengjin formula, we find the existence conditions for fixed points of the model. Then, by using the qualitative theory of ordinary differential equations and matrix theory we indicate which points are hyperbolic and which are non-hyperbolic and the associated conditions. 展开更多
关键词 Discrete Predator-Prey Model Non-Hyperbolic Fixed point NODE Saddle point
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