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Treatment of Skeletal CL II Patient with Maximum Lower Incisor Protrusion and Minimum Overjet with Rahhal Functional Appliance
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作者 Ahmad Abdallah Rahhal 《Open Journal of Stomatology》 2018年第12期319-325,共7页
Treatment of skeletal Cl II includes functional orthopedic treatment, head-gears, extraction of the upper premolars and orthognathic surgery. To treat any patient with functional appliances (bite jumping) an adequate ... Treatment of skeletal Cl II includes functional orthopedic treatment, head-gears, extraction of the upper premolars and orthognathic surgery. To treat any patient with functional appliances (bite jumping) an adequate overjet is necessary. In this case an 11 years old female patient has skeletal CLII due to mandibular deficiency with ANB angle 8 degrees, overbite: 3 mm, overjet: 1 mm, extremely convex profile and underdeveloped chin due to the hyper muscle contraction of the lower lip to obtain oral seal. To obtain an adequate overjet lower first premolars were extracted and maximum retraction using mini screws (for maximum anchorage) was applied. Afterwards Rahhal functional appliance was used by the patient 16 hours a day for 6 months and 10 hours a day for another 6 months for retention. After that fixed orthodontic treatment was completed. Lateral cephalometrics were taken, traced and analyzed. In the result Skeletal CLI was obtained (ANB 4 degree), straight facial profile, normal over bite overjet and particular chin development were noticed. As a conclusion, in skeletal CLII malocclusions, lower incisor protrusion will cause a contraindication for functional treatment. Extraction of the lower premolars and retraction of the lower incisors followed by functional orthopedic treatment is an efficient method to treat these cases instead of waiting for orthognathic surgery, also reducing the muscle pressure on the chin will change the development characteristics of it. 展开更多
关键词 Rahhal functional appliance Lower INCISOR PROTRUSION minimum Overjet maximum aNCHORaGE CHIN Development
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On the Distribution of the Minimum or Maximum of a Random Number of i.i.d. Lifetime Random Variables
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作者 Francisco Louzada Estela MPBereta Maria APFranco 《Applied Mathematics》 2012年第4期350-353,共4页
Statisticians are usually concerned with the proposition of new distributions. In this paper we point out that a unified and concise derivation procedure of the distribution of the minimum or maximum of a random numbe... Statisticians are usually concerned with the proposition of new distributions. In this paper we point out that a unified and concise derivation procedure of the distribution of the minimum or maximum of a random number N of indepen-dent and identically distributed continuous random variables Yi,{i = 1,2,…,N} is obtained if one compounds the probability generating function of N with the survival or the distribution func-tion of Yi. Expressions are then derived in closed form for the density, hazard and quantile func-tions of the minimum or maximum. The methodology is illustrated with examples of the distributions proposed by Adamidis and Loukas (1998), Kus (2007), Tahmasbi and Rezaei (2008), Barreto-Souza and Cribari-Neto (2009), Cancho, Louzada, and Barriga (2011) and Louzada, Roman and Cancho (2011). 展开更多
关键词 Compounding Distributions Distribution of the maximum Distribution of the minimum Probability Generating function
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基于fminimax优化函数的圆度误差评定
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作者 赵则祥 赵新宇 《工具技术》 北大核心 2024年第5期129-136,共8页
依据圆度误差标注代号和附加符号的含义,基于最小外接法、最大内切法和最小区域法分别建立了参考圆的圆心坐标优化目标函数和圆度误差评定模型,采用MATLAB软件编写了参考圆的圆心坐标优化目标函数子程序和圆度误差评定子程序,给出了圆... 依据圆度误差标注代号和附加符号的含义,基于最小外接法、最大内切法和最小区域法分别建立了参考圆的圆心坐标优化目标函数和圆度误差评定模型,采用MATLAB软件编写了参考圆的圆心坐标优化目标函数子程序和圆度误差评定子程序,给出了圆度误差评定中fminimax优化函数调用方法。用Talyrond 585LT圆柱度测量仪对三个试样的圆周轮廓进行了提取,基于最小二乘法、最小外接法、最大内切法和最小区域法对提取的圆周轮廓分别进行了圆度误差评定。研究了优化搜索范围对圆度误差评定结果的影响,并将fminimax优化函数圆度误差评定的优化符合度与其他优化方法圆度误差评定的优化符合度进行了比较。fminimax优化函数的应用结果表明,评定结果精度高于或等于其他优化方法评定结果的精度,可满足圆度误差评定的需要。 展开更多
关键词 圆度误差 最小外接法 最大内切法 最小区域法 fminimax优化函数
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Extreme value distributions of mixing two sequences with different MDA's 被引量:2
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作者 蒋岳祥 《Journal of Zhejiang University Science》 CSCD 2004年第5期509-517,共9页
Suppose {Xi, i≥1} and {Yi, i≥1} are two independent sequences with distribution functions FX(x) and FY(x), respectively. Zi is the combination of Xi and Yi with a probability pn for each i with 1≤i≤n. The extreme ... Suppose {Xi, i≥1} and {Yi, i≥1} are two independent sequences with distribution functions FX(x) and FY(x), respectively. Zi is the combination of Xi and Yi with a probability pn for each i with 1≤i≤n. The extreme value distribution ,n GZ(x) of this particular triangular array of the i.i.d. random variables Z1, , Z2, ,…, Zn n n ,nis discussed. We found a new form of the extreme value distribution ΛA(ρx)Λ(x)(0<ρ <1), which is not max-stable. It occurs if FX(x) and FY(x) belong to the same MDA(Λ). GZ(x) does not exist as mixture forms of the different types of extreme value distributions. 展开更多
关键词 Extreme value distribution maximum domain of attraction(MDa) Mixed distribution functions
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Likelihood and Quadratic Distance Methods for the Generalized Asymmetric Laplace Distribution for Financial Data 被引量:1
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作者 Andrew Luong 《Open Journal of Statistics》 2017年第2期347-368,共22页
Maximum likelihood (ML) estimation for the generalized asymmetric Laplace (GAL) distribution also known as Variance gamma using simplex direct search algorithms is investigated. In this paper, we use numerical direct ... Maximum likelihood (ML) estimation for the generalized asymmetric Laplace (GAL) distribution also known as Variance gamma using simplex direct search algorithms is investigated. In this paper, we use numerical direct search techniques for maximizing the log-likelihood to obtain ML estimators instead of using the traditional EM algorithm. The density function of the GAL is only continuous but not differentiable with respect to the parameters and the appearance of the Bessel function in the density make it difficult to obtain the asymptotic covariance matrix for the entire GAL family. Using M-estimation theory, the properties of the ML estimators are investigated in this paper. The ML estimators are shown to be consistent for the GAL family and their asymptotic normality can only be guaranteed for the asymmetric Laplace (AL) family. The asymptotic covariance matrix is obtained for the AL family and it completes the results obtained previously in the literature. For the general GAL model, alternative methods of inferences based on quadratic distances (QD) are proposed. The QD methods appear to be overall more efficient than likelihood methods infinite samples using sample sizes n ≤5000 and the range of parameters often encountered for financial data. The proposed methods only require that the moment generating function of the parametric model exists and has a closed form expression and can be used for other models. 展开更多
关键词 M-ESTIMaTORS CUMULaNT Generating function CHI-SQUaRE Tests Generalized Hyperbolic Distribution SIMPLEX Pattern Search Variance Gamma minimum Distance VaLUE at RISK Entropic VaLUE at RISK European Call Option
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Extreme value distributions of mixing two sequences with the same MDA
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作者 蒋岳祥 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2004年第3期86-93,共8页
Suppose {Xi, i 1} and {Yi, i 1} are two independent sequences with distribution functions ()XFx and ()YFx, respectively. Zi,n is the combination of Xi and Yi with a probability np for each i with 1 in. The extreme val... Suppose {Xi, i 1} and {Yi, i 1} are two independent sequences with distribution functions ()XFx and ()YFx, respectively. Zi,n is the combination of Xi and Yi with a probability np for each i with 1 in. The extreme value distribution GZ(x) of this particular triangular array of the i.i.d. random variables Z1,n, Z2,n, ,L Zn,n is discussed. We found a new form of the extreme value distributions i) 12()()AxxaaFF and ii) 12()()AxxaaYY (a1<a2), which are not max-stable. It occurs if FX and FY belong to the same MDA(? or MDA(?. 展开更多
关键词 EXTREME value DISTRIBUTION maximum domain of aTTRaCTION (MDa) Mixed DISTRIBUTION functions
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Non-Vanishing Space Time Block Code for Three Time Slots and Two Transmit Antennas
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作者 Ali Azarbar 《Journal of Computer and Communications》 2015年第6期74-86,共13页
Recently, space time block codes (STBCs) are proposed for multi-input and multi-output (MIMO) antenna systems. Designing an STBC with both low decoding complexity and non-vanishing property for the Long Term Evolution... Recently, space time block codes (STBCs) are proposed for multi-input and multi-output (MIMO) antenna systems. Designing an STBC with both low decoding complexity and non-vanishing property for the Long Term Evolution Advanced (LTE-A) remains an open issue. In this paper, first our previously proposed STBC’s non-vanishing property will be completely described. The proposed STBC scheme has some interesting properties: 1) the scheme can achieve full rate and full diversity;2) its maximum likelihood (ML) decoding requires a joint detection of three real symbols;3) the minimum determinant values (MDVs) do not vanish by increasing signal constellation sizes;4) compatible with the single antenna transmission mode. The sentence has been dropped. Second, in order to improve BER performance, we propose a variant of proposed STBC. This scheme further decreases the detection complexity with a rate reduction of 33%;moreover, non-vanishing MDVs property is preserved. The simulation results show the second proposed STBC has better BER performance compared with other schemes. 展开更多
关键词 Space Time Block Codes maximum LIKELIHOOD DECODING Non-Vanishing minimum DETERMINaNT Value
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A class of not max-stable extreme value distributions
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作者 蒋岳祥 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第4期315-321,共7页
The sequences {Zi , 1≤i≤n}, n≥1 have multi-nomial distribution among i.i.d. random variables {X1, , i≥1}, {X2, , ,n i i i≥1}, …, {Xm , i≥1}. The extreme value distribution GZ(x) of this particular triangular ar... The sequences {Zi , 1≤i≤n}, n≥1 have multi-nomial distribution among i.i.d. random variables {X1, , i≥1}, {X2, , ,n i i i≥1}, …, {Xm , i≥1}. The extreme value distribution GZ(x) of this particular triangular array of i.i.d. random variables Z1, , Z2, , …, ,i n n r ?1 Zn is discussed in this paper. We found a new type of not max-stable extreme value distributions, i) GZ (x) = ,n ∏Φα Ai(x)×Φαr (x); i i=1 r ?1 r?1 ii) GZ (x) = ∏Ψα Ai(x)×Ψαr (x); iii) GZ (x) = ∏Λ Ai(λix)×Λ(x), r≥2, 0<α1≤α2≤…≤αr and λi∈(0,1] for i, 1≤i≤r?1 which occur if i i=1 i=1 Fj, …, Fm belong to the same MDA. 展开更多
关键词 Extreme value distribution maximum domain of attraction (MDa) Mixed distribution functions
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Bits, Mass and Acceleration Issues in BSC
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作者 Giuseppe Fazio Mauro Giaconi Angela D'Arienzo Davide Quatrini 《Journal of Physical Science and Application》 2014年第8期531-535,共5页
The goal of the present paper is to expand already published works in the frame of"Banded speed cosmology" (BSC). In particular this paper gives validated values for physical quantities not so far investigated in ... The goal of the present paper is to expand already published works in the frame of"Banded speed cosmology" (BSC). In particular this paper gives validated values for physical quantities not so far investigated in previous publications, i.e., the number of individual physical entity in the universe, as well as the maximum value for acceleration. Validates values mean identical quantities from a numerical point of view obtained with different theoretical procedures, additionally compared with data based on NASA observations with Planck probe. 展开更多
关键词 Banded speed cosmology minimum and maximum value for the mass number of mass unities maximum value for acceleration Bekenstein.
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积分限函数∫_(x)^(x+a)|sin t|dt的最值及图形的拐点
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作者 张辉 方晓峰 郑丽娜 《河南财政金融学院学报(自然科学版)》 2024年第1期42-49,共8页
研究了一类特殊的积分限函数f(x)=∫_(x)^(x+a)|sin t|dt。首先分析得到函数f(x)是一个周期为π的周期可导函数,再利用微积分基本公式和积分限函数求导公式两种方法,分别研究函数f(x)的最值问题,然后利用拐点的判定方法得到曲线f(x)的... 研究了一类特殊的积分限函数f(x)=∫_(x)^(x+a)|sin t|dt。首先分析得到函数f(x)是一个周期为π的周期可导函数,再利用微积分基本公式和积分限函数求导公式两种方法,分别研究函数f(x)的最值问题,然后利用拐点的判定方法得到曲线f(x)的拐点坐标,最后对此积分限函数进行推广,并利用MATLAB软件画图验证,旨在更深入地理解和掌握积分限函数的性态。 展开更多
关键词 积分限函数 最值 拐点 微积分基本公式
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n人合作对策的shapley值与最大熵法 被引量:9
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作者 倪中新 《上海师范大学学报(自然科学版)》 1998年第2期8-13,共6页
从概率论的角度给出了shanley值的证明,又以信息论中最大熔原理作依据给出了n人合作对策的另一种解决方法,这种方法的适用范围比shapley值要广,体现了实体活动中信息的重要性,易于理解.
关键词 合作对策的特征函数 SHaPLEY值 最大熵原理
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基于Copula方法的极值洪水频率与风险分析 被引量:1
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作者 欧阳资生 王同辉 《统计与信息论坛》 CSSCI 2012年第1期71-76,共6页
洪灾风险分析中的一项重要内容是关于洪水发生概率(频率)的估计。以湖南省四大水系中的四个站点50多年的年最高水位数据为基础,结合常用于灾害分析中的分布模型估计出每个站点的洪水频率分布,再利用Copula函数模型得到两两水系间水位协... 洪灾风险分析中的一项重要内容是关于洪水发生概率(频率)的估计。以湖南省四大水系中的四个站点50多年的年最高水位数据为基础,结合常用于灾害分析中的分布模型估计出每个站点的洪水频率分布,再利用Copula函数模型得到两两水系间水位协同变化的联合分布函数,进而估计每两条河流同时发生洪水灾害的概率。 展开更多
关键词 洪水频率分析 年最大水位Copula函数 极值分布
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基于改进蚁群算法的智能车路径规划研究
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作者 吴蕾 邴志刚 刘佳 《自动化与仪表》 2025年第1期72-76,共5页
该文针对智能车路径规划问题,提出一种改进蚁群算法的路径规划方法。传统蚁群算法虽有良好适应性,但也存在效率低下和易陷入局部最优等问题。为此,该文引入势场启发式函数和信息素奖惩策略,优化启发函数和信息素更新机制,提高算法全局... 该文针对智能车路径规划问题,提出一种改进蚁群算法的路径规划方法。传统蚁群算法虽有良好适应性,但也存在效率低下和易陷入局部最优等问题。为此,该文引入势场启发式函数和信息素奖惩策略,优化启发函数和信息素更新机制,提高算法全局搜索能力和收敛速度。通过最大最小蚂蚁系统保持信息素多样性,有效避免局部最优,并采用路径二次优化策略简化路径,减少长度。实验结果表明,改进算法在复杂环境下有更快的收敛速度和更高的路径质量,为智能车路径规划提供了一种有效的优化策略。 展开更多
关键词 蚁群算法 势场启发式函数 信息素奖惩策略 最大最小蚂蚁系统 路径规划
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基于Eviews与GS Copula的金融市场相依性研究
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作者 霍俊爽 张若东 +1 位作者 邰志艳 董小刚 《吉林大学学报(信息科学版)》 CAS 2015年第6期690-693,共4页
为解决金融市场间波动的相依性问题,对不同金融市场间高频数据极小值的相依性进行研究。在分析GS Copula函数的模型方法和模型特点基础上,研究了估计GS Copula函数中参数的方法及正尾部相依性和负尾部相依性的模型,并基于Eviews软件和GS... 为解决金融市场间波动的相依性问题,对不同金融市场间高频数据极小值的相依性进行研究。在分析GS Copula函数的模型方法和模型特点基础上,研究了估计GS Copula函数中参数的方法及正尾部相依性和负尾部相依性的模型,并基于Eviews软件和GS Copula函数等理论对上证000001指数和股指期货IF1112指数5 min极小值的收益率序列数据的相依性进行了分析,得出其收益率序列数据有很强的上尾部相依性。为在金融决策中降低风险提供了理论依据。 展开更多
关键词 EVIEWS软件 GS Copula函数 极小值 相依性
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Banach空间中一阶终值问题解的存在性 被引量:1
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作者 肖艳萍 张申贵 《甘肃联合大学学报(自然科学版)》 2006年第3期17-19,共3页
在紧型条件下,运用Sadovskii不动点定理,讨论了Banach空间中一阶常微分方程终值问题最大解与最小解的存在性.
关键词 BaNaCH空间 终值问题 最大解与最小解 非紧性测度
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Banach 空间二阶非线性混合型脉冲积分微分方程的边值问题
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作者 吴兆荣 苗巧云 邵先喜 《青岛大学学报(工程技术版)》 CAS 1997年第3期71-74,共4页
研究了Banach空间二阶非线性混合型脉冲积分微分方程的边值问题,证明了解与最大解和最小解的存在性。
关键词 非线性混合型 脉冲 积分微分方程 边值
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关于函数y=mx+n((ax^2)+bx+c)^(1/2)值域和最值的注记
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作者 孙千高 王学功 《青海师专学报》 1996年第3期78-80,共3页
讨论并解决形如函数的值域和最值问题。
关键词 值域 增函数 函数 最大值 最小值
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基于Copula模型的最大和最小值期权定价 被引量:1
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作者 曹朵 卢俊香 张转转 《河南科学》 2019年第9期1519-1526,共8页
为了克服传统Black-Scholes定价模型中标的资产收益率需要服从正态分布以及在多维资产期权定价中对复杂微分方程的求解和冗长公式等难题,利用非参数核密度方法和Copula函数对最大和最小值期权进行定价.应用非参数核密度方法确定标的资... 为了克服传统Black-Scholes定价模型中标的资产收益率需要服从正态分布以及在多维资产期权定价中对复杂微分方程的求解和冗长公式等难题,利用非参数核密度方法和Copula函数对最大和最小值期权进行定价.应用非参数核密度方法确定标的资产的边缘密度函数和分布函数,选择了对数据拟合效果最好的Gumbel函数连接边际分布并构造联合分布函数.通过Matlab对基于Copula函数的两资产最大和最小值期权的非参数定价模型进行积分运算.最后得出两资产的最大和最小值期权价格. 展开更多
关键词 最大值期权 最小值期权 COPULa函数 非参数方法 定价
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Funar猜想的证明
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作者 王开贤 《青岛大学学报(自然科学版)》 CAS 2006年第4期8-12,共5页
针对Funar猜想:“设任意三角形位于闭单位正方形内,则该三角形的内切圆半径,r≤(5-1)/4”,研究了与其等价的某二元函数的最小值问题;利用对此二元函数驻点及其取值、边界取值讨论,证明了等价问题成立,进而此Funar猜想得证。
关键词 Funar猜想 三角形的内切圆半径 二元函数 最大(最小)值问题 驻点
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关于用Lagrange乘数法求函数最值的充分条件 被引量:1
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作者 沈晨 宋冬梅 刘珊 《河南科学》 2012年第1期24-26,共3页
对于多元函数在约束条件下的最值问题,给出了有关充分条件及其对具体问题的应用.
关键词 多元函数 最值 LaGRaNGE乘数法 半正定阵
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