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On the Solution to the Separated Equation in the 3-Particle Calogero-Moser Problem
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作者 Natalia Inozemtseva Jaroslav Dittrich Vladimir Inozemtsev 《Advances in Pure Mathematics》 2018年第3期266-271,共6页
We propose the exact solution of the equation in separated variable which appears in the process of constructing solutions to the quantum Calogero-Moser three-particle problem with elliptic two-particle potential . Th... We propose the exact solution of the equation in separated variable which appears in the process of constructing solutions to the quantum Calogero-Moser three-particle problem with elliptic two-particle potential . This solution is found for special values of coupling constants . It can be used for solving three-particle Calogero-Moser problem under the appropriate boundary conditions. 展开更多
关键词 Calogero-Moser Model 3-particle problem Separation of VARIABLES
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中药调控PI3K/Akt信号通路干预多囊卵巢综合征大鼠实验研究的现状、问题及对策 被引量:2
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作者 闫朋宣 刘奕清 +4 位作者 咸楠星 彭麟景 李鲲 张京春 赵雨坤 《中国实验方剂学杂志》 北大核心 2025年第1期259-266,共8页
多囊卵巢综合征(PCOS)及其导致的不孕症是妇科和生殖内分泌科常见的疾病之一。磷脂酰肌醇3-激酶/蛋白激酶B(PI3K/Akt)信号通路是干预PCOS发展研究相对较多的信号通路,中药通过此信号通路开展的PCOS大鼠实验也是机制研究的主要方向。笔... 多囊卵巢综合征(PCOS)及其导致的不孕症是妇科和生殖内分泌科常见的疾病之一。磷脂酰肌醇3-激酶/蛋白激酶B(PI3K/Akt)信号通路是干预PCOS发展研究相对较多的信号通路,中药通过此信号通路开展的PCOS大鼠实验也是机制研究的主要方向。笔者通过相应标准梳理并筛选出了近5年在学术期刊公开发表的文章20篇,从基线资料、造模与治疗、分组情况、评价性指标、药效学指标5个方面对入选的研究客观情况、存在问题进行分析,结果发现各个研究项目均存在不同程度的问题,如造模观察指标、模型成功判断标准、治疗周期、方药/有效成分剂量计算方式和具体用量等未明确,易造成结果偏倚或降低实验数据有效度。基于此,形成了PCOS大鼠实验研究操作清单,涉及实验大鼠、模型构建、研究实施、结局指标和分析与报告五大类共21条操作清单,以期为后续PCOS实验有关科研提供参考,助力形成高质量成果。 展开更多
关键词 中医药(TCM) 多囊卵巢综合征(PCOS) 磷脂酰肌醇3-激酶/蛋白激酶B(PI3K/Akt)信号通路 现状及问题 动物模型 肾虚型 蛋白
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Why is the Danger Cylinder Dangerous in the P3P Problem? 被引量:5
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作者 ZHANG Cai-Xia HU Zhan-Yi 《自动化学报》 EI CSCD 北大核心 2006年第4期504-511,共8页
The PnP problem is a widely used technique for pose determination in computer vision community,and finding out geometric conditions of multiple solutions is the ultimate and most desirable goal of the multi-solution a... The PnP problem is a widely used technique for pose determination in computer vision community,and finding out geometric conditions of multiple solutions is the ultimate and most desirable goal of the multi-solution analysis,which is also a key research issue of the problem.In this paper,we prove that given 3 control points,if the camera's optical center lies on the so-called“danger cylinder”and is enough far from the supporting plane of control points,the corresponding P3P problem must have 3 positive solutions.This result can bring some new insights into a better understanding of the multi-solution problem.For example,it is shown in the literature that the solution of the P3P problem is instable if the optical center lies on this danger cylinder,we think such occurrence of triple-solution is the primary source of this instability. 展开更多
关键词 The P3P problem the danger cylinder instability of solution
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随机正则3-(d,k)-SAT问题的可满足性相变
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作者 王晓峰 唐傲 +4 位作者 彭庆媛 颜冬 华盈盈 何飞 王军霞 《华中科技大学学报(自然科学版)》 北大核心 2025年第10期42-48,83,共8页
受随机正则恰当(d,k)-SAT(可满足性)问题的特征启发,提出了随机正则3-(d,k)-SAT问题.首先,引入了随机正则3-(d,k)-SAT问题实例生成模型,用于产生随机正则(d,k)-CNF(合取范式)公式.该模型采用完美匹配机制,每个随机完美匹配都对应一个随... 受随机正则恰当(d,k)-SAT(可满足性)问题的特征启发,提出了随机正则3-(d,k)-SAT问题.首先,引入了随机正则3-(d,k)-SAT问题实例生成模型,用于产生随机正则(d,k)-CNF(合取范式)公式.该模型采用完美匹配机制,每个随机完美匹配都对应一个随机正则3-(d,k)-SAT实例.然后,结合一阶矩方法、二阶矩方法和正则(d,k)-CNF公式的解空间结构,给出了当k>3时,随机正则3-(d,k)-SAT问题的可满足性相变点dk.当d>dk时,随机正则(d,k)-CNF实例公式高概率3-恰当不可满足;当d<dk时,随机正则(d,k)-CNF实例公式高概率3-恰当可满足.最后,分别取变元规模n=10,k=6和n=15,k=10的两组数据集进行实验.实验结果表明:随机正则3-(d,k)-SAT问题存在相变现象,分别发生在d_(6)=1.407 4和d_(10)=1.962 4附近,验证了理论证明所得相变点的正确性. 展开更多
关键词 相变现象 随机正则3-(d k)-SAT问题 矩方法 正则(d k)-CNF公式 生成模型
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Key Problems of Cold Power Spinning of Ti-15-3 Alloy 被引量:1
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作者 Debin SHAN Yan LU and Ping LI School of Materials Science and Engineering, Harbin institute of Thchnology, Harbin 150001, China Yi XU Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110015, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2001年第1期125-126,共2页
The key problems of cold power spinning of Ti-15-3 alloy are studied. Reasonable billet preparation methods are presented to improve crystal structure and avoid crack of billet. Influences of original wall thickness,... The key problems of cold power spinning of Ti-15-3 alloy are studied. Reasonable billet preparation methods are presented to improve crystal structure and avoid crack of billet. Influences of original wall thickness, reduction rate and feed rate on expanding in diameter are analyzed and some methods to prevent expanding in diameter are given. 展开更多
关键词 TI Key problems of Cold Power Spinning of Ti-15-3 Alloy
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An adiabatic quantum optimization for exact cover 3 problem
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作者 张映玉 许丽莉 李俊青 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第3期139-141,共3页
A perturbation method is applied to study the structure of the ground state of the adiabatic quantum optimization for the exact cover 3 problem. It is found that the instantaneous ground state near the end of the evol... A perturbation method is applied to study the structure of the ground state of the adiabatic quantum optimization for the exact cover 3 problem. It is found that the instantaneous ground state near the end of the evolution is mainly composed of the eigenstates of the problem Hamiltonian, which are Hamming close to the solution state. And the instantaneous ground state immediately after the starting is mainly formed of low energy eigenstates of the problem Hamiltonian. These results are then applied to estimate the minimum gap for a special case. 展开更多
关键词 adiabatic quantum optimization exact cover 3 problem perturbation expansion
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Approximation Schemes for the 3-Partitioning Problems
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作者 Jianbo Li Honglin Ding 《Communications and Network》 2013年第1期90-95,共6页
The 3-partitioning problem is to decide whether a given multiset of nonnegative integers can be partitioned into triples that all have the same sum. It is considerably used to prove the strong NP-hardness of many sche... The 3-partitioning problem is to decide whether a given multiset of nonnegative integers can be partitioned into triples that all have the same sum. It is considerably used to prove the strong NP-hardness of many scheduling problems. In this paper, we consider four optimization versions of the 3-partitioning problem, and then present four polynomial time approximation schemes for these problems. 展开更多
关键词 3-partitioning problem APPROXIMATION SCHEME
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Structure Formation and Non Linear Electrodynamics with Attendant Changes in Gravitational Potential and Its Relationship to the 3 Body Problem
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作者 Andrew Walcott Beckwith 《Journal of High Energy Physics, Gravitation and Cosmology》 2018年第4期779-786,共8页
We find that having the scale factor close to zero due to a given magnetic field value, an early universe magnetic field affects how we would interpret Mukhanov’s chapter on “self reproduction of the universe”. We ... We find that having the scale factor close to zero due to a given magnetic field value, an early universe magnetic field affects how we would interpret Mukhanov’s chapter on “self reproduction of the universe”. We extend such arguments, and refer to the possibility of modified gravity. We hope that some of the issues raised by Kobayashi and Seto as to allowed inflation models may be addressed, once further refinement of these preliminary results commences. We close with statements as to the value of α in a gravitational potential proportional to r?α and how this adjustment affects the 3 body problem. 展开更多
关键词 INFLATION Modified GRAVITY 3 BODY problem
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GENERALIZED UPWIND SCHEME WITH FRACTIONAL STEPS FOR 3-D PROBLEM OF CONVECTION DOMINATING GROUNDWATER TRANSPORT
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作者 姚磊华 《Journal of Coal Science & Engineering(China)》 1997年第2期68-72,共5页
A generalized upwind scheme with fractional steps for 3-D mathematical models of convection dominating groundwater quality is suggested. The mass transport equation is split into a convection equation and a dispersive... A generalized upwind scheme with fractional steps for 3-D mathematical models of convection dominating groundwater quality is suggested. The mass transport equation is split into a convection equation and a dispersive equation. The generalized upwind scheme is used to solve the convection equation and the finite element method is used to compute the dispersive equation.These procedures which not only overcome the phenomenon of the negative concentration and numerical dispersion appear frequently with normal FEM or FDM to solve models of convection dominating groundwater transport but also avoid the step for computing each node velocity give a more suitable method to calculate the concentrations of the well points. 展开更多
关键词 3-D problem of groundwater transport convection dominating fractional step generalized upwind scheme
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The Analysis of Convergence for the 3<i>X</i>+ 1 Problem and Crandall Conjecture for the a<i>X</i>+ 1 Problem
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作者 Zuojun Hu 《Advances in Pure Mathematics》 2021年第5期400-407,共8页
The 3X + 1 problem (Collatz conjecture) has been proposed for many years, however no major breakthrough has been made so far. As we know, the Crandall conjecture is a well-known generalization of the 3X + 1 problem. I... The 3X + 1 problem (Collatz conjecture) has been proposed for many years, however no major breakthrough has been made so far. As we know, the Crandall conjecture is a well-known generalization of the 3X + 1 problem. It is worth noting that, both conjectures are infamous for their simplicity in stating but intractability in solving. In this paper, I aim to provide a clear explanation about the reason why these two problems are difficult to handle and have very different characteristics on convergence of the series via creatively applying the probability theory and global expectancy value E(n) of energy contraction index. The corresponding convergence analysis explicitly shows that a = 3 leads to a difficult problem, while a > 3 leads to a divergent series. To the best of my knowledge, this is the first work to point out the difference between these cases. The corresponding results not only propose a new angle to analyze the 3X + 1 problem, but also shed some light on the future research. 展开更多
关键词 3X + 1 problem Crandall Conjecture Energy Method Expectancy Theory
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On the Change Rule of 3x + 1 Problem
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作者 Ke Li 《Journal of Applied Mathematics and Physics》 2022年第3期850-864,共15页
This article introduces a change rule of 3x + 1 problem (Collatz conjecture), it’s named LiKe’s Rule. It’s a map of 3x + 1 problem, and details the path of each step of the change: For any positive integer, change ... This article introduces a change rule of 3x + 1 problem (Collatz conjecture), it’s named LiKe’s Rule. It’s a map of 3x + 1 problem, and details the path of each step of the change: For any positive integer, change by the Collatz conjecture. 1) This positive integer will change to an odd number;2) The odd number must change to a number of LiKe’s second sequence {3<sup>n</sup> – 1| n ∈ Z<sup>+</sup>};3) Then this 3<sup>n</sup> - 1 will change to a smaller 3<sup>n </sup>– 1 and gradually decrease to 8 (that is 3<sup>2</sup> - 1) then back to 1 in the end. If we can determine each step, the Collatz conjecture will be true. This is certainly more valuable than 2<sup>n</sup> (it might even explain 2<sup>n</sup>). And to illustrate the importance of this rule, introduced some important funny corollaries related to it. 展开更多
关键词 3x +1 problem Collatz-problem Collatz Conjecture LiKe’s Rule Number Theory
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Numerical Solution of Some Diffusion Problems in 3-Layered 3D Domain
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作者 Harijs Kalis Ilmars Kangro Aigars Gedroics 《Journal of Mathematics and System Science》 2013年第6期309-318,共10页
In this paper we consider averaging and finite difference methods for solving the 3-D boundary-value problem in a multilayered domain. We consider the metal concentration in the 3 layered peat blocks. Using experiment... In this paper we consider averaging and finite difference methods for solving the 3-D boundary-value problem in a multilayered domain. We consider the metal concentration in the 3 layered peat blocks. Using experimental data the mathematical model for calculating the concentration of metal at different points in peat layers is developed. A specific feature of these problems is that it is necessary to solve the 3-D boundary-value problems for the partial differential equations (PDEs) of the elliptic type of second order with piece-wise diffusion coefficients in the three layer domain. We develop here a finite-difference method for solving a problem of the above type with the periodical boundary condition in x direction. This procedure allows reducing the 3-D problem to a system of 2-D problems by using a circulant matrix. 展开更多
关键词 3D diffusion problem finite difference method averaged method heavy metals Ca Fe peat bog.
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父母教养方式和儿童体育活动与3~4岁儿童睡眠问题的关联研究 被引量:1
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作者 吴燕 叶孙岳 《中国儿童保健杂志》 北大核心 2025年第3期259-264,共6页
目的 探讨父母教养方式、儿童体育活动与3~4岁儿童睡眠问题的关系,为改善幼儿睡眠问题提供依据。方法 采用随机抽样方式,于2022年3—4月在嘉兴市抽取3所普通公立幼儿园的347名3~4岁儿童。以《儿童睡眠习惯问卷》总分(>41分)定义为儿... 目的 探讨父母教养方式、儿童体育活动与3~4岁儿童睡眠问题的关系,为改善幼儿睡眠问题提供依据。方法 采用随机抽样方式,于2022年3—4月在嘉兴市抽取3所普通公立幼儿园的347名3~4岁儿童。以《儿童睡眠习惯问卷》总分(>41分)定义为儿童睡眠问题。采用Logistic回归模型分析父母教养方式与儿童睡眠问题的关系,采用调节效应模型分析儿童体育活动的调节作用。结果 父亲和母亲的支持/参与教养行为与儿童睡眠问题呈负相关(父:OR=0.941,95%CI:0.903~0.980;母:OR=0.938,95%CI:0.901~0.977),而父亲和母亲的敌意/强制教养行为与儿童睡眠问题呈正相关(父:OR=1.034,95%CI:1.002~1.067;母:OR=1.038,95%CI:1.005~1.072)。儿童体育活动对父母敌意/强制或支持/参与教养行为与儿童睡眠问题的关联有显著调节作用(P<0.05)。结论 父母积极的教养行为与3~4岁儿童睡眠问题的减少有关,父母的消极教养行为与儿童睡眠问题的增加有关,而儿童的体育活动在教养方式和儿童睡眠问题之间起调节作用,且儿童每天体育活动达到2h时,就可以缓冲父母教养方式对儿童发生睡眠问题的不良影响。3~4岁儿童的睡眠可能受益于改善父母教养方式和促进儿童体育活动水平的策略。 展开更多
关键词 父母教养方式 睡眠问题 体育活动 3~4岁儿童
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Modeling and Comprehensive Review of Signaling Storms in 3GPP-Based Mobile Broadband Networks:Causes,Solutions,and Countermeasures
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作者 Muhammad Qasim Khan Fazal Malik +1 位作者 Fahad Alturise Noor Rahman 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期123-153,共31页
Control signaling is mandatory for the operation and management of all types of communication networks,including the Third Generation Partnership Project(3GPP)mobile broadband networks.However,they consume important a... Control signaling is mandatory for the operation and management of all types of communication networks,including the Third Generation Partnership Project(3GPP)mobile broadband networks.However,they consume important and scarce network resources such as bandwidth and processing power.There have been several reports of these control signaling turning into signaling storms halting network operations and causing the respective Telecom companies big financial losses.This paper draws its motivation from such real network disaster incidents attributed to signaling storms.In this paper,we present a thorough survey of the causes,of the signaling storm problems in 3GPP-based mobile broadband networks and discuss in detail their possible solutions and countermeasures.We provide relevant analytical models to help quantify the effect of the potential causes and benefits of their corresponding solutions.Another important contribution of this paper is the comparison of the possible causes and solutions/countermeasures,concerning their effect on several important network aspects such as architecture,additional signaling,fidelity,etc.,in the form of a table.This paper presents an update and an extension of our earlier conference publication.To our knowledge,no similar survey study exists on the subject. 展开更多
关键词 Signaling storm problems control signaling load analytical modeling 3GPP networks smart devices diameter signaling mobile broadband data access data traffic mobility management signaling network architecture 5G mobile communication
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遗传算法和3-opt结合求解带有能力约束的VRP 被引量:26
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作者 张涛 王梦光 《东北大学学报(自然科学版)》 EI CAS CSCD 北大核心 1999年第3期254-256,共3页
描述了带有能力约束的车辆路径问题(VRP),在预先不固定车辆数的情况下,把聚类和排序有机地结合起来,并用遗传算法和3opt算法相结合的混合算法对问题进行求解,实验结果表明算法获得的最好解、平均负荷率和计算成本都比较... 描述了带有能力约束的车辆路径问题(VRP),在预先不固定车辆数的情况下,把聚类和排序有机地结合起来,并用遗传算法和3opt算法相结合的混合算法对问题进行求解,实验结果表明算法获得的最好解、平均负荷率和计算成本都比较令人满意· 展开更多
关键词 车辆路径问题 遗传算法 3-opt算法 能力约束 VRP
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镇江市3~7岁儿童行为问题流行病学调查 被引量:8
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作者 常宪鲁 张燕 王华云 《中国妇幼保健》 CAS 北大核心 2011年第28期4412-4414,共3页
目的:探讨镇江市3~7岁儿童行为问题的流行病学特点,为减少儿童行为问题的发生提供干预措施。方法:应用Conners父母症状问卷(Parent Symptom Questionnaire,PSQ)和自编儿童行为影响因素调查表对724名3~7岁城乡儿童进行调查。结果:3~7... 目的:探讨镇江市3~7岁儿童行为问题的流行病学特点,为减少儿童行为问题的发生提供干预措施。方法:应用Conners父母症状问卷(Parent Symptom Questionnaire,PSQ)和自编儿童行为影响因素调查表对724名3~7岁城乡儿童进行调查。结果:3~7岁儿童行为问题检出率为13.1%,男童检出率为17.0%,女童检出率为9.2%,两者相比差异有统计学意义(P<0.01)。男女童在品行问题上差异有统计学意义(P<0.05),在冲动多动及多动指数上差异有统计学意义(P<0.01)。单因素分析发现对3~7岁儿童行为问题有影响的因素有母亲孕期焦虑或抑郁、孕期身体健康状况、父亲文化、产期合并症、儿童既往史以及儿童开始讲话时间。多元逐步回归分析发现孕期焦虑或抑郁、孕期身体健康状况不良、产期合并症是行为问题发生的主要危险因素。结论:儿童行为问题是多因素作用的结果,孕妇保持良好情绪及减少产期合并症对减少儿童行为问题有重要意义。 展开更多
关键词 行为问题 3~7岁儿童 流行病学
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一种求解3-SAT问题的新方法 被引量:6
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作者 贺毅朝 王彦祺 寇应展 《计算机工程与应用》 CSCD 北大核心 2006年第16期70-72,共3页
可满足性问题(SatisfiabilityProblem,SAT)是计算科学的典型问题之一,目前有DP算法、SAT1.3算法和遗传算法等多种求解方法。文章根据Kennedy和Eberhart提出的二进制粒子群优化算法(BinaryParticleSwarmOptimizers),基于局部随机搜索策略... 可满足性问题(SatisfiabilityProblem,SAT)是计算科学的典型问题之一,目前有DP算法、SAT1.3算法和遗传算法等多种求解方法。文章根据Kennedy和Eberhart提出的二进制粒子群优化算法(BinaryParticleSwarmOptimizers),基于局部随机搜索策略,给出了一种求解3-SAT问题的新方法:基于局部随机搜索的改进二进制粒子群优化算法(ModifedBinaryParticleSwarmOptimizersBasedonlocalstochasticsearch,简称MBPSO)。数值实验表明,对于随机产生的3-SAT问题测试实例,该算法是一种高效实用的新方法。 展开更多
关键词 3-SAT问题 合取范式 PSO算法 局部搜索
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兰州市181名2~3岁儿童行为问题调查分析 被引量:4
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作者 杨兰 李佳樾 +7 位作者 南楠 何莉 刘月芬 岳莉 王燕侠 王称 丁丽玮 朱瑛 《中国儿童保健杂志》 CAS 2016年第9期961-964,共4页
目的了解兰州市2~3岁幼儿期儿童行为问题的现状及影响因素,促进儿童心理健康。方法采用Achenbach 2~3岁儿童行为量表(CBCL)中国标准化版本(家长用)和自编相关因素调查表对兰州市181名儿童进行调查。结果兰州市2~3岁儿童行为问题检... 目的了解兰州市2~3岁幼儿期儿童行为问题的现状及影响因素,促进儿童心理健康。方法采用Achenbach 2~3岁儿童行为量表(CBCL)中国标准化版本(家长用)和自编相关因素调查表对兰州市181名儿童进行调查。结果兰州市2~3岁儿童行为问题检出率为15.5%,其中男童检出率14.3%,女童检出率17.1%;男女童在行为问题各因子上的差异无统计学意义(P〉0.05);在社交退缩、抑郁、睡眠问题、躯体诉述、破坏行为、内向性和总行为问题因子上的得分显著高于常模(P〈0.01);在攻击行为、外向性因子上的得分显著低于常模(P〈0.001);父母文化程度是儿童行为问题的一个重要影响因素。结论兰州市2~3岁儿童行为问题较为突出,尤其是社交退缩、内向性问题,有必要加强早期综合发展指导,开展综合性干预。 展开更多
关键词 2~3岁儿童 行为问题 影响因素
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图3-着色问题的O(2^n)链数DNA计算机算法 被引量:2
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作者 李肯立 周旭 许进 《电子学报》 EI CAS CSCD 北大核心 2008年第11期2096-2101,共6页
随着DNA计算的不断发展,如何克服穷举算法带来的指数爆炸问题已成为DNA计算领域的重要研究目标之一.为减少图3-着色问题DNA计算机算法中的DNA链数,本文将Adleman-Lipton模型生物操作与粘贴模型解空间相结合的DNA计算模型进行扩展,通过... 随着DNA计算的不断发展,如何克服穷举算法带来的指数爆炸问题已成为DNA计算领域的重要研究目标之一.为减少图3-着色问题DNA计算机算法中的DNA链数,本文将Adleman-Lipton模型生物操作与粘贴模型解空间相结合的DNA计算模型进行扩展,通过设计顶点着色器、稀疏图/稠密图搜索器,提出一种用于求解图3-着色问题的DNA计算模型与算法.将本算法与同类算法对比分析表明:本算法在保持多项式操作时间的条件下,将求解n个顶点的图3-着色问题所需DNA分子链数从O(3n)减少至O(2n),改进了3-着色问题同类文献的研究结果. 展开更多
关键词 DNA超级计算 3-着色问题 剪枝策略 NP完全问题
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植物种群-3/2幂自疏定律假设的点评 被引量:3
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作者 王仁忠 方林 +2 位作者 卢文祥 姜世成 王平 《东北师大学报(自然科学版)》 CAS CSCD 1998年第4期58-62,共5页
通过对国外大量研究报道的综合分析,详细阐述了-3/2幂自疏定律假设的概念、表达式、发展及存在的问题,旨在澄清对植物种群-3/2幂自疏定律假设的认识,推动我国植物种群密度制约机制研究的发展.
关键词 植物种群 自疏定律假设 种群动态 种群密度
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