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Petrophysical Evaluation of Cape Three Points Reservoirs
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作者 Striggner Bedu-Addo Sylvester Kojo Danuor Larry Pax Chegbeleh 《International Journal of Geosciences》 CAS 2024年第2期162-179,共18页
The findings of a study to ascertain and assess the petrophysical characteristics of Cape Three Points reservoirs in the Western basin with a view to describe the reservoir quantitatively using Well Logs, Petrel and T... The findings of a study to ascertain and assess the petrophysical characteristics of Cape Three Points reservoirs in the Western basin with a view to describe the reservoir quantitatively using Well Logs, Petrel and Techlog. The investigated characteristics, which were all deduced from geophysical wire-line logs, include lithology, porosity, permeability, fluid saturation, and net to gross thickness. To characterise the reservoir on the field, a suite of wire-line logs including gamma ray, resistivity, spontaneous potential, and density logs for three wells (WELL_1X, WELL_2X, and WELL_3X) from the Tano Cape Three Point basin were studied. The analyses that were done included lithology delineation, reservoir identification, and petrophysical parameter determination for the identified reservoirs. The tops and bases of the three wells analysed were marked at a depth of 1203.06 - 2015.64 m, 3863.03 - 4253.85 m and 2497.38 - 2560.32 m respectively. There were no hydrocarbons in the reservoirs from the studies. The petrophysical parameters computed for each reservoir provided porosities of 13%, 3% and 11% respectively. The water saturation also determined for these three wells (WELL_1X, WELL_2X and WELL_3X) were 94%, 95% and 89% respectively. These results together with the behaviour of the density and neutron logs suggested that these wells are wildcat wells. 展开更多
关键词 Petrophysical Cape Three points RESERVOIRS
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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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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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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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Traffic prediction enabled dynamic access points switching for energy saving in dense networks
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作者 Yuchao Zhu Shaowei Wang 《Digital Communications and Networks》 SCIE CSCD 2023年第4期1023-1031,共9页
To meet the ever-increasing traffic demand and enhance the coverage of cellular networks,network densification is one of the crucial paradigms of 5G and beyond mobile networks,which can improve system capacity by depl... To meet the ever-increasing traffic demand and enhance the coverage of cellular networks,network densification is one of the crucial paradigms of 5G and beyond mobile networks,which can improve system capacity by deploying a large number of Access Points(APs)in the service area.However,since the energy consumption of APs generally accounts for a substantial part of the communication system,how to deal with the consequent energy issue is a challenging task for a mobile network with densely deployed APs.In this paper,we propose an intelligent AP switching on/off scheme to reduce the system energy consumption with the prerequisite of guaranteeing the quality of service,where the signaling overhead is also taken into consideration to ensure the stability of the network.First,based on historical traffic data,a long short-term memory method is introduced to predict the future traffic distribution,by which we can roughly determine when the AP switching operation should be triggered;second,we present an efficient three-step AP selection strategy to determine which of the APs would be switched on or off;third,an AP switching scheme with a threshold is proposed to adjust the switching frequency so as to improve the stability of the system.Experiment results indicate that our proposed traffic forecasting method performs well in practical scenarios,where the normalized root mean square error is within 10%.Furthermore,the achieved energy-saving is more than 28% on average with a reasonable outage probability and switching frequency for an area served by 40 APs in a commercial mobile network. 展开更多
关键词 Access points switching on/off ENERGY-SAVING Green network Long short-term memory Traffic prediction
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Solving Fractional Differential Equations via Fixed Points of Chatterjea Maps
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作者 Nawab Hussain Saud M.Alsulami Hind Alamri 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第6期2617-2648,共32页
In this paper,we present the existence and uniqueness of fixed points and common fixed points for Reich and Chatterjea pairs of self-maps in complete metric spaces.Furthermore,we study fixed point theorems for Reich a... In this paper,we present the existence and uniqueness of fixed points and common fixed points for Reich and Chatterjea pairs of self-maps in complete metric spaces.Furthermore,we study fixed point theorems for Reich and Chatterjea nonexpansive mappings in a Banach space using the Krasnoselskii-Ishikawa iteration method associated withSλand consider some applications of our results to prove the existence of solutions for nonlinear integral and nonlinear fractional differential equations.We also establish certain interesting examples to illustrate the usability of our results. 展开更多
关键词 Common fixed points Reich and Chatterjea mappings Krasnoselskii-Ishikawa iteration complete metric space Banach space integral equation nonlinear fractional differential equation
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Approach for Predicting the Knowledge Points of Math Questions
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作者 Kui Xiao Kong Huang +1 位作者 Zhifang Huang Hao Chen 《计算机教育》 2023年第12期114-123,共10页
In order to provide high-quality learning services,various online systems should possess the fundamental ability to predict the knowledge points and units to which a given test question belongs.The existing methods ty... In order to provide high-quality learning services,various online systems should possess the fundamental ability to predict the knowledge points and units to which a given test question belongs.The existing methods typically rely on manual labeling or traditional machine learning methods.Manual labeling methods have high time costs and high demands for human resources,while traditional machine learning methods only focus on the shallow features of the topics,ignoring the deep semantic relationship between the topic text and the knowledge point units.These two methods have relatively large limitations in practical applications.This paper proposes a convolutional neural network method combined with multiple features to predict the knowledge point units.We construct a binary classification dataset in the three grades of primary mathematics.Considering the supplementary role of Pinyin to Chinese text and the unique identification characteristics of Unicode encoding for characters,we obtain the Pinyin representation and the Unicode encoding representation of the original Chinese text.Then,we put the three representation methods into the convolutional neural network for training,obtain three kinds of semantic vectors,fuse them,and finally obtain higher-dimensional fusion features.Our experimental results demonstrate that our approach achieves good performance in predicting the knowledge units of test questions. 展开更多
关键词 Knowledge points PREDICTION Fusion features Convolutional neural network
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Key Review Points on Cosmetic Labeling and Relevant Cases
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作者 Li Neng 《China Detergent & Cosmetics》 2023年第1期29-37,共9页
Interpreted the latest cosmetic labeling requirements one by one from the basic principles on labels,content, positions, preceded terms and so on;analyzed the relevant cases, so as to help cosmetic manufacturers and o... Interpreted the latest cosmetic labeling requirements one by one from the basic principles on labels,content, positions, preceded terms and so on;analyzed the relevant cases, so as to help cosmetic manufacturers and operation enterprises to deeply understand the latest requirements on cosmetics labeling after the promulgation of the new regulations. 展开更多
关键词 China cosmetic labeling review points
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Effects of sowing date and ecological points on yield and the temperature and radiation resources of semi-winter wheat 被引量:1
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作者 ZHANG Zhen-zhen CHENG Shuang +7 位作者 FAN Peng ZHOU Nian-bing XING Zhi-peng HU Ya-jie XU Fang-fu GUO Bao-wei WEI Hai-yan ZHANG Hong-cheng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第5期1366-1380,共15页
Exploring the effects of sowing date and ecological points on the yield of semi-winter wheat is of great significance.This study aims to reveal the effects of sowing date and ecological points on the climate resources... Exploring the effects of sowing date and ecological points on the yield of semi-winter wheat is of great significance.This study aims to reveal the effects of sowing date and ecological points on the climate resources associated with wheat yield in the Rice–Wheat Rotation System.With six sowing dates,the experiments were carried out in Donghai and Jianhu counties,Jiangsu Province,China using two semi-winter wheat varieties as the objects of this study.The basic seedlings of the first sowing date (S1) were planted at 300×10^(4)plants ha^(-1),which was increased by 10%for each of the delayed sowing dates (S2–S6).The results showed that the delay of sowing date decreased the number of days,the effective accumulated temperature and the cumulative solar radiation in the whole growth period.The yields of S1 were higher than those of S2 to S6 by 0.22–0.31,0.5–0.78,0.86–0.98,1.14–1.38,and 1.36–1.59 t ha^(–1),respectively.For a given sowing date,the growth days increased as the ecological point was moved north,while both mean daily temperature and effective accumulative temperature decreased,but the cumulative radiation increased.As a result,the yields at Donghai County were 0.01–0.39 t ha–1lower than those of Jianhu County for the six sowing dates.The effective accumulative temperature and cumulative radiation both had significant positive correlations with yield.The average temperature was significantly negatively correlated with the yield.The decrease in grain yield was mainly due to the declines in grains per spike and 1 000-grain weight caused by the increase in the daily temperature and the decrease in the effective accumulative temperature. 展开更多
关键词 wheat YIELD SOWING DATE ECOLOGICAL point
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Slope deformation partitioning and monitoring points optimization based on cluster analysis
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作者 LI Yuan-zheng SHEN Jun-hui +3 位作者 ZHANG Wei-xin ZHANG Kai-qiang PENG Zhang-hai HUANG Meng 《Journal of Mountain Science》 SCIE CSCD 2023年第8期2405-2421,共17页
The scientific and fair positioning of monitoring locations for surface displacement on slopes is a prerequisite for early warning and forecasting.However,there is no specific provision on how to effectively determine... The scientific and fair positioning of monitoring locations for surface displacement on slopes is a prerequisite for early warning and forecasting.However,there is no specific provision on how to effectively determine the number and location of monitoring points according to the actual deformation characteristics of the slope.There are still some defects in the layout of monitoring points.To this end,based on displacement data series and spatial location information of surface displacement monitoring points,by combining displacement series correlation and spatial distance influence factors,a spatial deformation correlation calculation model of slope based on clustering analysis was proposed to calculate the correlation between different monitoring points,based on which the deformation area of the slope was divided.The redundant monitoring points in each partition were eliminated based on the partition's outcome,and the overall optimal arrangement of slope monitoring points was then achieved.This method scientifically addresses the issues of slope deformation zoning and data gathering overlap.It not only eliminates human subjectivity from slope deformation zoning but also increases the efficiency and accuracy of slope monitoring.In order to verify the effectiveness of the method,a sand-mudstone interbedded CounterTilt excavation slope in the Chongqing city of China was used as the research object.Twenty-four monitoring points deployed on this slope were monitored for surface displacement for 13 months.The spatial location of the monitoring points was discussed.The results show that the proposed method of slope deformation zoning and the optimized placement of monitoring points are feasible. 展开更多
关键词 Excavation slope Surface displacement monitoring Spatial deformation analysis Clustering analysis Slope deformation partitioning Monitoring point optimization
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Motion Planning for a Cable-Driven Lower Limb Rehabilitation Robot with Movable Distal Anchor Points
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作者 Jinghang Li Keyi Wang +1 位作者 Yanzhuo Wang Chao Wang 《Journal of Bionic Engineering》 SCIE EI CSCD 2023年第4期1585-1596,共12页
This article introduces a cable-driven lower limb rehabilitation robot with movable distal anchor points(M-CDLR).The traditional cable-driven parallel robots(CDPRs)control the moving platform by changing the length of... This article introduces a cable-driven lower limb rehabilitation robot with movable distal anchor points(M-CDLR).The traditional cable-driven parallel robots(CDPRs)control the moving platform by changing the length of cables,M-CDLR can also adjust the position of the distal anchor point when the moving platform moves.The M-CDLR this article proposed has gait and single-leg training modes,which correspond to the plane and space motion of the moving platform,respectively.After introducing the system structure configuration,the generalized kinematics and dynamics of M-CDLR are established.The fully constrained CDPRs can provide more stable rehabilitation training than the under-constrained one but requires more cables.Therefore,a motion planning method for the movable distal anchor point of M-CDLR is proposed to realize the theoretically fully constrained with fewer cables.Then the expected trajectory of the moving platform is obtained from the motion capture experiment,and the motion planning of M-CDLR under two training modes is simulated.The simulation results verify the effectiveness of the proposed motion planning method.This study serves as a basic theoretical study of the structure optimization and control strategy of M-CDLR. 展开更多
关键词 Bionic robot Cable-driven parallel robot(CDPR) Lower limb rehabilitation robot Movable anchor point Motion planning SIMULATION
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Observation points classifier ensemble for high-dimensional imbalanced classification
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作者 Yulin He Xu Li +3 位作者 Philippe Fournier‐Viger Joshua Zhexue Huang Mianjie Li Salman Salloum 《CAAI Transactions on Intelligence Technology》 SCIE EI 2023年第2期500-517,共18页
In this paper,an Observation Points Classifier Ensemble(OPCE)algorithm is proposed to deal with High-Dimensional Imbalanced Classification(HDIC)problems based on data processed using the Multi-Dimensional Scaling(MDS)... In this paper,an Observation Points Classifier Ensemble(OPCE)algorithm is proposed to deal with High-Dimensional Imbalanced Classification(HDIC)problems based on data processed using the Multi-Dimensional Scaling(MDS)feature extraction technique.First,dimensionality of the original imbalanced data is reduced using MDS so that distances between any two different samples are preserved as well as possible.Second,a novel OPCE algorithm is applied to classify imbalanced samples by placing optimised observation points in a low-dimensional data space.Third,optimization of the observation point mappings is carried out to obtain a reliable assessment of the unknown samples.Exhaustive experiments have been conducted to evaluate the feasibility,rationality,and effectiveness of the proposed OPCE algorithm using seven benchmark HDIC data sets.Experimental results show that(1)the OPCE algorithm can be trained faster on low-dimensional imbalanced data than on high-dimensional data;(2)the OPCE algorithm can correctly identify samples as the number of optimised observation points is increased;and(3)statistical analysis reveals that OPCE yields better HDIC performances on the selected data sets in comparison with eight other HDIC algorithms.This demonstrates that OPCE is a viable algorithm to deal with HDIC problems. 展开更多
关键词 classifier ensemble feature transformation high-dimensional data classification imbalanced learning observation point mechanism
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A Machine Learning-Based Distributed Denial of Service Detection Approach for Early Warning in Internet Exchange Points
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作者 Salem Alhayani Diane R.Murphy 《Computers, Materials & Continua》 SCIE EI 2023年第8期2235-2259,共25页
The Internet service provider(ISP)is the heart of any country’s Internet infrastructure and plays an important role in connecting to theWorld WideWeb.Internet exchange point(IXP)allows the interconnection of two or m... The Internet service provider(ISP)is the heart of any country’s Internet infrastructure and plays an important role in connecting to theWorld WideWeb.Internet exchange point(IXP)allows the interconnection of two or more separate network infrastructures.All Internet traffic entering a country should pass through its IXP.Thus,it is an ideal location for performing malicious traffic analysis.Distributed denial of service(DDoS)attacks are becoming a more serious daily threat.Malicious actors in DDoS attacks control numerous infected machines known as botnets.Botnets are used to send numerous fake requests to overwhelm the resources of victims and make them unavailable for some periods.To date,such attacks present a major devastating security threat on the Internet.This paper proposes an effective and efficient machine learning(ML)-based DDoS detection approach for the early warning and protection of the Saudi Arabia Internet exchange point(SAIXP)platform.The effectiveness and efficiency of the proposed approach are verified by selecting an accurate ML method with a small number of input features.A chi-square method is used for feature selection because it is easier to compute than other methods,and it does not require any assumption about feature distribution values.Several ML methods are assessed using holdout and 10-fold tests on a public large-size dataset.The experiments showed that the performance of the decision tree(DT)classifier achieved a high accuracy result(99.98%)with a small number of features(10 features).The experimental results confirmthe applicability of using DT and chi-square for DDoS detection and early warning in SAIXP. 展开更多
关键词 Internet exchange point Saudi Arabia IXP(SAIXP) distributed denial of service CHI-SQUARE feature selection machine learning
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Natural forest ALS-TLS point cloud data registration without control points
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作者 Jianpeng Zhang Jinliang Wang +3 位作者 Feng Cheng Weifeng Ma Qianwei Liu Guangjie Liu 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第3期809-820,共12页
Airborne laser scanning(ALS)and terrestrial laser scanning(TLS)has attracted attention due to their forest parameter investigation and research applications.ALS is limited to obtaining fi ne structure information belo... Airborne laser scanning(ALS)and terrestrial laser scanning(TLS)has attracted attention due to their forest parameter investigation and research applications.ALS is limited to obtaining fi ne structure information below the forest canopy due to the occlusion of trees in natural forests.In contrast,TLS is unable to gather fi ne structure information about the upper canopy.To address the problem of incomplete acquisition of natural forest point cloud data by ALS and TLS on a single platform,this study proposes data registration without control points.The ALS and TLS original data were cropped according to sample plot size,and the ALS point cloud data was converted into relative coordinates with the center of the cropped data as the origin.The same feature point pairs of the ALS and TLS point cloud data were then selected to register the point cloud data.The initial registered point cloud data was fi nely and optimally registered via the iterative closest point(ICP)algorithm.The results show that the proposed method achieved highprecision registration of ALS and TLS point cloud data from two natural forest plots of Pinus yunnanensis Franch.and Picea asperata Mast.which included diff erent species and environments.An average registration accuracy of 0.06 m and 0.09 m were obtained for P.yunnanensis and P.asperata,respectively. 展开更多
关键词 Airborne laser scanning(ALS) Terrestrial laser scanning(TLS) REGISTRATION Natural forest Iterative closest point(ICP)algorithm
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Second Hankel Determinants and Fekete-Szegö Inequalities for Some Sub-Classes of Bi-Univalent Functions with Respect to Symmetric and Conjugate Points Related to a Shell Shaped Region 被引量:2
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作者 Rayaprolu Bharavi Sharma Kalikota Rajya Laxmi 《Analysis in Theory and Applications》 CSCD 2018年第4期358-373,共16页
In this paper, we have investigated second Hankel determinants and FeketeSzeg? inequalities for some subclasses of Bi-univalent functions with respect to symmetric and Conjugate points which are subordinate to a shell... In this paper, we have investigated second Hankel determinants and FeketeSzeg? inequalities for some subclasses of Bi-univalent functions with respect to symmetric and Conjugate points which are subordinate to a shell shaped region in the open unit disc ?. 展开更多
关键词 Analytic functions univalent functions Bi-univalent functions second Hankel determinants Fekete-Szegö inequalities symmetric points conjugate points
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LOCAL AND GLOBAL EXPOSED POINTS
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作者 M.Beltagy(Mathematics Department,Faculty of Science Tanta University,Egypt.) 《Acta Mathematica Scientia》 SCIE CSCD 1995年第3期335-341,共7页
LOCALANDGLOBALEXPOSEDPOINTSM.Beltagy(MathematicsDepartment,FacultyofScienceTantaUniversity,Egypt.)Abstract:I... LOCALANDGLOBALEXPOSEDPOINTSM.Beltagy(MathematicsDepartment,FacultyofScienceTantaUniversity,Egypt.)Abstract:Inthispaperwederiv... 展开更多
关键词 EXPOSED points STRICT CONVEXITY FOCAL points.
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Comparison of clinical efficacy of neddle knife at acupoints selected from recent regions along meridians and according to anatomical structures in treating early and middle stage knee osteoarthritis
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作者 Tian-Song Ding Xiang-Dong Tian +5 位作者 Ye Huang Ye-Tong Tan Guang-Yu Zhu Chang-Xiao Han Han-Dong Chen Wei Zhang 《Journal of Hainan Medical University》 2021年第22期17-22,共6页
Objective:To stimulate tenderness points around knee joint in two metholds-corresponding acupoints selected from recent regions along meridians and anatomical structures,to compare the clinical efficacy of neddle knif... Objective:To stimulate tenderness points around knee joint in two metholds-corresponding acupoints selected from recent regions along meridians and anatomical structures,to compare the clinical efficacy of neddle knife of to cure early and middle stage knee osteoarthritis.Method:70 patients were randomly(Random Number Tables)divided into test group(acupoints selected from recent regions along meridians,n=35)and control group(anatomical structures,n=35),who were diagnosed as knee osteoarthritis.Observe the VAS(visual analogue scale),Lysholm,WOMAC(the Western Ontario and McMaster Unive rsities Osteoarthritis Index)and ROM(rang of motion)between two groups in first week,first month,third month after treatment.Recording the degree of improvement of knee joint’s pain,dysfunction and symptoms of osteoarthritis and rang of motion.Results:Within groups,the VAS,Lysholm,WOMAC and ROM were obviously different from pre-therapy scores in the third,sixth and twelfth week post-therapy(P<0.05).Between groups no significant difference were observed in the third week post-therapy about VAS,Lysholm,WOMAC scores(P>0.05).However,there were differences in the sixth,twelfth weeks post-therapy(P<0.05);compared with control group,the ROM of test group were difference in the third,sixth,twelfth weeks post-therapy(P<0.05).Conclusion:The clinical efficacy of stimulating corresponding acupoints tenderness points selected from recent regions along meridians to treat early and middle stage knee osteoarthritis was superior to anatomical structures,which can effectively relieve pain,dysfunction,symptoms of osteoarthritis of knee joint and rang of motion. 展开更多
关键词 Knee osteoarthritis Knee arthralgia Needle knife Acupoints selected from recent regions along meridians Anatomical structures Tenderness points
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基于knee points的改进多目标人工蜂群算法 被引量:4
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作者 刘明辉 李炜 《计算机工程与应用》 CSCD 北大核心 2018年第2期40-47,共8页
传统的人工蜂群算法(Artificial Bee Colony algorithm,ABC)及其在多目标上的扩展(Multi Objective Artificial Bee Colony algorithm,MOABC)存在着在高维、多峰函数情况下收敛速度变慢、后期容易陷入局部最优以及寻优精度丢失等问题。... 传统的人工蜂群算法(Artificial Bee Colony algorithm,ABC)及其在多目标上的扩展(Multi Objective Artificial Bee Colony algorithm,MOABC)存在着在高维、多峰函数情况下收敛速度变慢、后期容易陷入局部最优以及寻优精度丢失等问题。基于knee points提高收敛性和分布性的特点,设计了一种快速识别knee point的算法并将其应用到多目标人工蜂群算法中,提出了一种基于knee points的改进多目标人工蜂群算法(Kn MOABC)。算法在迭代过程中考虑pareto支配关系的同时,优先选择knee point作为下一代个体,极大地增强了算法的收敛速度,同时,在knee point识别算法中加入自适应的策略以保持良好的分布性。实验结果表明,Kn MOABC的性能优于三个最新的多目标人工蜂群对比算法。 展开更多
关键词 多目标人工蜂群算法 高维多峰函数 KNEE points 自适应识别策略
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Spatial Pattern and Influencing Factor Analysis of Attended Collection and Delivery Points in Changsha City, China 被引量:3
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作者 XUE Shuyan LI Gang +3 位作者 YANG Lan LIU Ling NIE Qifan Muhammad Sajid MEHMOOD 《Chinese Geographical Science》 SCIE CSCD 2019年第6期1078-1094,共17页
Attended collection and delivery points are vital components of ‘last-mile logistics’.Based on point of interest(POI) data for Cainiao Stations and China Post stations in Changsha City, China, this paper provides a ... Attended collection and delivery points are vital components of ‘last-mile logistics’.Based on point of interest(POI) data for Cainiao Stations and China Post stations in Changsha City, China, this paper provides a detailed exploration of the basic features, spatial distribution, and location influencing factors of attended collection and delivery points.Specifically, analyses of the types, service objects and location distributions of the attended collection and delivery points alongside a discussion of their spatial pattern and influencing factors provides a reference for their general geographic layout and characteristics.The findings of this study indicate that: 1) The main mode of operation of attended collection and delivery points is franchises, with other modes of operation rely on supermarkets and other individual shop types.2) The main service targets of attended collection and delivery points are communities, schools, and businesses, followed by townships, enterprises, scenic spots, and administrative units.3) Approximately 77.44% of the attended collection and delivery points are located near the exits of service areas;others are situated in the centre of the service areas.For the Cainiao Stations, 80% are located within 125 m of the exit;for the China Post stations, 80% are located within 175 m of the exit.4) The spatial distribution of the attended collection and delivery points in Changsha is unbalanced, with ‘more centre and fewer surrounding’.The centre is an ‘inverted triangle’, and the edge is an ‘orphan’, showing a northwest-southeast orientation and symmetrical along the axis.The layout of the attended collection and delivery points forms three core areas, and the number of sites decreases with the distance from the core.5) The number and distribution of the attended collection and delivery points are strongly consistent with the regional economic development level, population, and roadway system traffic convenience.Most attended collection and delivery points are on residential, scientific and educational, and commercial and financial land. 展开更多
关键词 attended COLLECTION and delivery points Cainiao STATIONS China POST STATIONS spatial PATTERN influencing FACTORS Changsha China
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APPROXIMATE SOLUTION FOR THIN PLATES CONSTRAINED AT ARBITRARY POINTS 被引量:3
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作者 陈晓 周贤宾 《Chinese Journal of Aeronautics》 SCIE EI CSCD 1998年第4期69-74,共6页
Thebendingofplatessupportedbyhingesorpilarsundertransverseloadsisverycommoninarchitecture,mechanicalengineer... Thebendingofplatessupportedbyhingesorpilarsundertransverseloadsisverycommoninarchitecture,mechanicalengineering,etc.Especialy... 展开更多
关键词 ORTHOTROPIC thin plate large DEFLECTION ARBITRARY points CONSTRAINT
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