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基于宫颈癌前病变患者的癌症治疗功能评价系统-共性模块量表最小临床重要性差值的影响因素研究 被引量:4
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作者 杨玉丽 井明霞 +2 位作者 胡欣 杨萍 闫小龙 《中国全科医学》 CAS 北大核心 2023年第17期2108-2113,2119,共7页
背景生命质量量表的最小临床重要性差值(MCID)是解释和定义量表评分变化的重要参数,可促进生命质量量表作为治疗及干预效果评价工具在临床上的应用。MCID可能受多种因素的影响,目前关于癌症治疗功能评价系统-共性模块量表(FACT-G)MCID... 背景生命质量量表的最小临床重要性差值(MCID)是解释和定义量表评分变化的重要参数,可促进生命质量量表作为治疗及干预效果评价工具在临床上的应用。MCID可能受多种因素的影响,目前关于癌症治疗功能评价系统-共性模块量表(FACT-G)MCID的研究较少。目的 采用多种方法制订宫颈癌前病变患者FACT-G MCID,并分析患者社会人口学特征对FACT-G MCID的影响,为临床医生判断干预措施的临床有效性提供量化依据。方法 纳入2020年10月至2021年11月于石河子大学第一附属医院接受宫颈癌前病变相关手术治疗的66例宫颈癌前病变患者为研究对象。收集患者社会人口学及疾病相关信息,并采用FACT-G对患者术前及术后1个月生命质量进行评估。利用锚定法和分布法制订MCID。采用多元线性回归分析探讨FACT-G MCID的影响因素。结果 选择总体变化自评问卷(GRCQ)、36条目简明健康测量量表(SF-36量表)第10条目、五水平欧洲五维度健康量表(EQ-5D-5L)的效用值(UI)、视觉模拟尺度(EQ-VAS)四种锚,锚定法制订的FACT-G总分的MCID为7.048~12.932,分布法制订的FACT-G总分的MCID为3.696~10.243,锚定法和分布法制订的MCID不一致。以GRCQ为锚制订的MCID为例,筛选出术后轻微改善患者34例,多元线性回归分析结果表明,单身(β=15.264,P<0.001)、肥胖(β=-4.830,P=0.038)、基线FACT-G总分>89.5分(β=-7.600,P=0.001)是宫颈癌前病变患者FACT-G总分MCID的影响因素。结论 不同计算方法制订的FACT-G MCID不同。对于不同特征的宫颈癌前病变患者,应选择不同的FACT-G MCID来判断临床决策的有效性及治疗后生命质量变化是否具有临床相关性。 展开更多
关键词 宫颈上皮内瘤样病变 子宫疾病 癌症治疗功能评价系统-共性模块 最小临床重要性差值 影响因素分析 线性模型
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COMPARISON BETWEEN TWO ANALYTICAL MODELS OF HELICOPTER GROUND RESONANCE
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作者 刘强 张晓谷 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1995年第1期92-98,共7页
The 2-dimensional equivalent model used in helicopter ground resonance analysis is convenient for its simplicity and clarity. The equivalent body mass, the stiffness and the damping are derived from the modal charaCte... The 2-dimensional equivalent model used in helicopter ground resonance analysis is convenient for its simplicity and clarity. The equivalent body mass, the stiffness and the damping are derived from the modal charaCteristics. In this paper, a 3-dimensional space model is constructed to analyse the ground resonance.There is little difference between the calculated results of the 2-dimensional equivalent model and those of the 3-dimensional space model. Hence, the 2-dimensional model is verified for the practical application. Generally, the linear lead-lag damping of the equivalent rotor blade at the modal frequency is derived from the lead-lag damper characteristics by a procedure of iteration. The transformation of the imaginary part of the complex modulus of the viscoelastic damper into a linear velocity damping is complicated in analysis. A method to use the complex modulus directly in the ground resonance analysis is derived and verified. 展开更多
关键词 HELICOPTER dynamic stability RESONANCE equivalent model rotor/body coupling
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地县一体化整定计算软件中的实用性问题研究
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作者 俞京锋 阮远峰 +1 位作者 孟伟 李雪冬 《智能电网(汉斯)》 2015年第6期271-275,共5页
本文通过调研现有整定计算软件的常用功能和使用经验,针对整定计算软件存在的若干实用性问题,从运行方式、供电方案、整定模式和定值通知单等方面分析了现有整定计算软件存在的不足,提出了利用厂站组合、手动整定、保护装置模板共性量... 本文通过调研现有整定计算软件的常用功能和使用经验,针对整定计算软件存在的若干实用性问题,从运行方式、供电方案、整定模式和定值通知单等方面分析了现有整定计算软件存在的不足,提出了利用厂站组合、手动整定、保护装置模板共性量解决对应的上述问题。本文阐述的方案更贴近用户使用,使整定软件更通用化、实用化,提高地县一体化整定计算模式下电网的安全可靠性。 展开更多
关键词 整定计算 供电方案 厂站组合 手动整定 共性量
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Non-Metric CCD Camera Calibration Algorithm in a Digital Photogrammetry System 被引量:4
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作者 YANG Hua-chao DENG Ka-zhong ZHANG Shu-bi GUO Guang-li ZHOU Ming 《Journal of China University of Mining and Technology》 EI 2006年第2期119-122,共4页
Camera calibration is a critical process in photogrammetry and a necessary step to acquire 3D information from a 2D image. In this paper, a flexible approach for CCD camera calibration using 2D direct linear transform... Camera calibration is a critical process in photogrammetry and a necessary step to acquire 3D information from a 2D image. In this paper, a flexible approach for CCD camera calibration using 2D direct linear transformation (DLT) and bundle adjustment is proposed. The proposed approach assumes that the camera interior orientation elements are known, and addresses a new closed form solution in planar object space based on homogenous coordinate representation and matrix factorization. Homogeneous coordinate representation offers a direct matrix correspondence between the parameters of the 2D DLT and the collinearity equation. The matrix factorization starts by recovering the elements of the rotation matrix and then solving for the camera position with the collinearity equation. Camera calibration with high precision is addressed by bundle adjustment using the initial values of the camera orientation elements. The results show that the calibration precision of principal point and focal length is about 0.2 and 0.3 pixels respectivelv, which can meet the requirements of close-range photogrammetry with high accuracy. 展开更多
关键词 direct linear transformation collinearity equation bundle adjustment camera calibration Hough transformation
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Audio steganalysis based on “negative resonance phenomenon” caused by steganographic tools 被引量:1
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作者 RU Xue-min ZHUANG Yue-ting WU Fei 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第4期577-583,共7页
Researching on the impact different steganographic software tools have audio statistical features, revealed the phe- nomenon that when messages are embedded in a WAV file by using a certain tool, the variation of stat... Researching on the impact different steganographic software tools have audio statistical features, revealed the phe- nomenon that when messages are embedded in a WAV file by using a certain tool, the variation of statistical features in the WAV file which already contains messages embedded by the same tool is abruptly smaller than those in which messages have not been embedded. We call it “negative resonance phenomenon” temporarily. With the phenomenon above and Support Vector Machines (SVMs), we can detect the existence of hidden messages, and also identify the tools used to hide them. As shown by the experi- mental results, the proposed method can be very effectively used to detect hidden messages embedded by Hide4PGP, Stegowav and S-Tools4. 展开更多
关键词 Audio steganalysis Linear prediction Support Vector Machine (SVM)
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Effect of Si content on laser welding performance of Al-Mn-Mg alloy
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作者 赵丕植 刘婧 迟之东 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第7期2208-2213,共6页
The correlation between Si content (0.1%-0.5%, mass fraction) and pulse laser welding performance of AI-Mn-Mg aluminum alloy sheets was studied. The sheets were fabricated in the laboratory, with gauge of 0.45 mm, H... The correlation between Si content (0.1%-0.5%, mass fraction) and pulse laser welding performance of AI-Mn-Mg aluminum alloy sheets was studied. The sheets were fabricated in the laboratory, with gauge of 0.45 mm, H16 temper by pulse laser welding. It was found that no cracking existed in the welding pool as Si content was below 0.34%. However, when the Si content increased to 0.47%, cracking formed in the welding pool. Microstructure observations indicated that residual eutectic phases distributed at the grain boundaries were discontinuous and appeared to be small particles in lower Si content alloys; the residual eutectic phases distributed at the grain boundaries were partially continuous and appeared to be films in higher Si content alloys. These phenomena could explain why Si content adversely affected the laser welding performance. 展开更多
关键词 Al-Mn-Mg alloy laser welding performance Si content CRACK residual eutectic phase
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Teleportation of N-qubit W State without Bell-State Measurement via Selective Resonant Interaction in Cavity QED 被引量:1
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作者 钟文学 耿珺 +1 位作者 程广玲 陈爱喜 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第8期253-256,共4页
We present a scheme in which the N-atom W state is teleported by employing the selective interactionof a cavity field with a driven three-level atom in the A configuration and detecting a single atom in one of the gro... We present a scheme in which the N-atom W state is teleported by employing the selective interactionof a cavity field with a driven three-level atom in the A configuration and detecting a single atom in one of the groundstates.The long-lived W state is teleported from atom A to atom B when the atoms B and A are sent through acavity successively and atom A is then detected.The advantage is that the present one does not involve the Bell-statemeasurement and is robust against the atomic spontaneous emission. 展开更多
关键词 TELEPORTATION W state Bell-state measurement selective resonant interaction
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Reexamining Security of Improved Multiparty Quantum Secret Splitting and Quantum State Sharing
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作者 林崧 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第6期1059-1061,共3页
In a recent letter [H.F. Wang, X. Ji, and S. Zhang, Phys. Lett. A 358 (2006) 11], an improvement of the multiparty quantum secret splitting and quantum state sharing protocol [F.G. Deng, et al., Phys. Lett. A 354 (... In a recent letter [H.F. Wang, X. Ji, and S. Zhang, Phys. Lett. A 358 (2006) 11], an improvement of the multiparty quantum secret splitting and quantum state sharing protocol [F.G. Deng, et al., Phys. Lett. A 354 (2006) 190.] was presented. We study the security of the improved protocol and find that two or more dishonest participants may recover the secret from the dealer. Hence we further modify the improved protocol, which make it stand against this kind of attack. 展开更多
关键词 quantum secret sharing entanglement swapping
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Conformal Invariance and Noether Symmetry, Lie Symmetry of Birkhoffian Systems in Event Space 被引量:4
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作者 张毅 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第1期166-170,共5页
This paper focuses on studying a conformal invariance and a Noether symmetry, a Lie symmetry for a Birkhoffian system in event space. The definitions of the conformal invariance of the system are given. By investigati... This paper focuses on studying a conformal invariance and a Noether symmetry, a Lie symmetry for a Birkhoffian system in event space. The definitions of the conformal invariance of the system are given. By investigation on the relations between the conformal invariance and the Noether symmetry, the conformal invariance and the Lie symmetry, the expressions of conformal factors of the system under these circumstances are obtained. The Noether conserved quantities and the Hojman conserved quantities directly derived from the conformal invariance are given. Two examples are given to illustrate the application of the results. 展开更多
关键词 Birkhoffian system event space conformal invariance Noether symmetry Lie symmetry
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Friction contact mechanisms of layered surface 被引量:1
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作者 Fan Xue Diao Dongfeng 《Engineering Sciences》 EI 2013年第1期15-22,共8页
In this paper,we firstly review the carbon layered surface prepared with electron cyclotron resonance (ECR) plasma sputtering. Secondly,the friction behavior of carbon layered surface under pin-on-disk testing is desc... In this paper,we firstly review the carbon layered surface prepared with electron cyclotron resonance (ECR) plasma sputtering. Secondly,the friction behavior of carbon layered surface under pin-on-disk testing is described. Furthermore,the contact stress evolution processes of layered surface with and without transfer layer during wear are given for understanding the contact mechanisms. Finally,a three-dimension (3D) local yield map of layered surface is introduced,which is useful to predict the possible contact mechanisms. 展开更多
关键词 layered surface FRICTION contact mechanism transfer layer ECR plasma sputtering PIN-ON-DISK
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Measurement and correlation of physical properties of aqueous solutions of tetrabutylammonium hydroxide, piperazine and their aqueous blends
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作者 Rizwan Safdar Abdul Aziz Omar +2 位作者 Lukman B.Ismail Arhama Bari Bhajan Lal 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第11期1811-1818,共8页
The density,viscosity and refractive index of aqueous solutions of tetrabutylammonium hydroxide(TBAOH),piperazine(PZ) and their aqueous blends are determined at several temperatures(303.15 to 333.15 K).All these measu... The density,viscosity and refractive index of aqueous solutions of tetrabutylammonium hydroxide(TBAOH),piperazine(PZ) and their aqueous blends are determined at several temperatures(303.15 to 333.15 K).All these measured physicochemical properties decreases with an increase in temperature.The density data is used to calculate the coefficient of thermal expansion and excess molar volume of all aqueous binary and ternary solutions.The coefficient of thermal expansion increases with increase in temperatures and concentrations.The negativity of excess molar volume for all the aqueous solution decreased with increase in temperature.Each physical property is correlated with temperature by least square method and the corresponding coefficients for each property are presented.The prediction values from correlations for the physical properties are in good agreement with the experimental values. 展开更多
关键词 DENSITY ionic liquidsDensityViscosityRefractive index
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Study of Nonpolaritons in a Kerr Nonlinear Optical Resonator
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作者 WAN Jin-Yin CHENG Ze 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第6期1107-1111,共5页
We find that in a Kerr nonlinear optical resonator, the photon system possesses a new kind of quasiparticle, the nonpolariton. The existence of nonpolaritons should be testified by observing the energy density depende... We find that in a Kerr nonlinear optical resonator, the photon system possesses a new kind of quasiparticle, the nonpolariton. The existence of nonpolaritons should be testified by observing the energy density dependence of the velocity and squeezing of nonpolaritons. As we have investigated, the transition energy density of a Kerr nonlinear optical resonator is larger than that of a normal state. 展开更多
关键词 Kerr nonlinear resonator nonpolariton average energy density
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Corresponding Factors Influencing Crude Oils Assay Using Low-field Nuclear Magnetic Resonance 被引量:4
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作者 Feng Yunxia Chu Xiaoli +1 位作者 Xu Yupeng Tian Songbai 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2014年第2期34-39,共6页
In this study, the main factors influencing the measurements by means of the off-line low-field 1H NMR in the lab were discussed base on a robust calibration model established by the PLS algorithm using 255 crude oil ... In this study, the main factors influencing the measurements by means of the off-line low-field 1H NMR in the lab were discussed base on a robust calibration model established by the PLS algorithm using 255 crude oil samples. The preheating temperature had a great influence on the viscosity of oil samples and the resolution of spectral analysis. The repeatability of spectral measurements was impacted by the metal and wax content of the oil samples. For the case of high wax content oils, the wax species began to crystallize in the course of determination that could affect the repeatability of spectral measurements. These factors have evidenced why the preheating devices and filter unit are necessary when low field NMR system is used in the online analysis process. The investigation is very important for the on-line application of the low field NMR. 展开更多
关键词 low-field NMR influencing factors crude oils assay
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Agility evaluation in public sector
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作者 Dahmardeh Nazar Pourshahabi Vahid 《Chinese Business Review》 2009年第10期19-24,共6页
Agility metrics are difficult to define in general, mainly due to the multidimensionality and vagueness of the concept of agility itself. In this paper, a knowledge-based framework is utilized for the measurement and ... Agility metrics are difficult to define in general, mainly due to the multidimensionality and vagueness of the concept of agility itself. In this paper, a knowledge-based framework is utilized for the measurement and assessment of public sector's agility by A. T. Kearney model. In this research, the authors used Z2 test in SPSS software. So, the authors discovered that the General Office of Standards & Industrial Research of Sistan & Baluchestan Province in Iran is agile. Finally, the authors determine the weakness points of organization by Friedman test. 展开更多
关键词 agility measuring agile government public sector
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Conformal Invariance and a New Type of Conserved Quantities of Mechanical Systems with Variable Mass in Phase Space
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作者 ZHANG Ming-Jiang FANG Jian-Hui LIN Peng LU Kai PANG Ting 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第10期561-564,共4页
Conformal invariance and a new type of conserved quantities of mechanical systems with variable mass in phase space are studied. Firstly, the definition and determining equation of conformal invariance are presented. ... Conformal invariance and a new type of conserved quantities of mechanical systems with variable mass in phase space are studied. Firstly, the definition and determining equation of conformal invariance are presented. The relationship between the conformal invariance and the Lie symmetry is given, and the necessary and sufficient condition that the conformal invarianee would be the Lie symmetry under the infinitesimal transformations is provided. Secondly, a new type of conserved quantities of the conformal invariance are obtained by using the Lie symmetry of the system. Lastly, an example is given to illustrate the application of the results. 展开更多
关键词 conformal invariance conserved quantity variable mass system phhse space
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On conformal vector fields on Randers manifolds 被引量:6
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作者 SHEN ZhongMin XIA QiaoLing 《Science China Mathematics》 SCIE 2012年第9期1869-1882,共14页
In this paper,we study conformal vector fields on a Randers manifold with certain curvature properties.In particular,we completely determine conformal vector fields on a Randers manifold of weakly isotropic flag curva... In this paper,we study conformal vector fields on a Randers manifold with certain curvature properties.In particular,we completely determine conformal vector fields on a Randers manifold of weakly isotropic flag curvature. 展开更多
关键词 Randers metric conformal vector field flag curvature navigation problem
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MRI can reveal metabolic changes in lily bulbs in vivo during dormancy release 被引量:3
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作者 HAN HaoJun YI MingFang 《Science China(Life Sciences)》 SCIE CAS 2012年第11期1002-1006,共5页
The factors influencing dormancy release in lily bulbs strongly affect commercialization success, but the mechanism of dormancy release is still unclear. Magnetic resonance imaging (MRI) can detect changes in morpholo... The factors influencing dormancy release in lily bulbs strongly affect commercialization success, but the mechanism of dormancy release is still unclear. Magnetic resonance imaging (MRI) can detect changes in morphology and water status in a living plant bulb and aid in investigating release factors. To evaluate whether MRI could be used to detect intra-bulb metabolic changes during the dormant period in Oriental Lilies (Lilium 'Sorbonne'), a series of MRI and sugar concentration measurements were performed weekly on bulbs stored for 11 weeks at 4°C. The image quality of intra-bulb structure obtained using T 1-weighted imaging was superior to that obtained using T 2 -weighted imaging and had a higher signal-to-noise ratio (0.97±0.01). Magnetization transfer ratio values for the bud and basal plate declined during the first eight weeks of cold storage (P>0.05), and were well correlated with concentration of soluble sugar in the bud (R 2 =0.95) and basal plate (R 2 =0.93). Thus, MRI can serve as a valuable tool for observation and analysis of dynamic morphological and metabolic changes in vivo during dormancy release. This information is potentially useful as a guide in the improvement of horticultural product quality. 展开更多
关键词 transverse and longitudinal relaxation times magnetization transfer ratio (MTR) soluble sugar magnetic resonanceimaging (MRI) Lilium oriental hybrids dormancy release
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Optimal four-impulse rendezvous between coplanar elliptical orbits 被引量:6
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作者 WANG JianXia BAOYIN HeXi +1 位作者 LI JunFeng SUN FuChun 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2011年第4期792-802,共11页
Rendezvous in circular or near circular orbits has been investigated in great detail, while rendezvous in arbitrary eccentricity elliptical orbits is not sufficiently explored. Among the various optimization methods p... Rendezvous in circular or near circular orbits has been investigated in great detail, while rendezvous in arbitrary eccentricity elliptical orbits is not sufficiently explored. Among the various optimization methods proposed for fuel optimal orbital rendezvous, Lawden's primer vector theory is favored by many researchers with its clear physical concept and simplicity in solu- tion. Prussing has applied the primer vector optimization theory to minimum-fuel, multiple-impulse, time-fixed orbital ren- dezvous in a near circular orbit and achieved great success. Extending Prussing's work, this paper will employ the primer vec- tor theory to study trajectory optimization problems of arbitrary eccentricity elliptical orbit rendezvous. Based on linearized equations of relative motion on elliptical reference orbit (referred to as T-H equations), the primer vector theory is used to deal with time-fixed multiple-impulse optimal rendezvous between two coplanar, coaxial elliptical orbits with arbitrary large ec- centricity. A parameter adjustment method is developed for the prime vector to satisfy the Lawden's necessary condition for the optimal solution. Finally, the optimal multiple-impulse rendezvous solution including the time, direction and magnitudes of the impulse is obtained by solving the two-point boundary value problem. The rendezvous error of the linearized equation is also analyzed. The simulation results confirmed the analyzed results that the rendezvous error is small for the small eccentric- ity case and is large for the higher eccentricity. For better rendezvous accuracy of high eccentricity orbits, a combined method of multiplier penalty function with the simplex search method is used for local optimization. The simplex search method is sensitive to the initial values of optimization variables, but the simulation results show that initial values with the primer vector theory, and the local optimization algorithm can improve the rendezvous accuracy effectively with fast convergence, because the optimal results obtained by the primer vector theory are already very close to the actual optimal solution. 展开更多
关键词 If the initial values are taken randomly it is difficult to converge to the optimal solution. elliptical orbit rendezvous primer vector fuel optimal
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Scalar Resonance at 750 GeV as Composite of Heavy Vector-Like Fermions
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作者 廖玮 郑汉青 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第8期219-223,共5页
We study a model of scalars which includes both the SM Higgs and a scalar singlet as composites of heavy vector-like fermions. The vector-like fermions are bounded by the super-strong four-fermion interactions. The sc... We study a model of scalars which includes both the SM Higgs and a scalar singlet as composites of heavy vector-like fermions. The vector-like fermions are bounded by the super-strong four-fermion interactions. The scalar singlet decays to SM vector bosons through loop of heavy vector-like fermions. We show that the surprisingly large production cross section of di-photon events at 750 GeV resonance and the odd decay properties can all be explained.This model serves as a good model for both SM Higgs and a scalar resonance at 750 GeV. 展开更多
关键词 composite Higgs
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Preparation and optical properties of GaSb nanoparticles embedded in SiO_2 composite films 被引量:1
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作者 刘发民 张立德 +1 位作者 贾俊辉 姜治 《Science China Mathematics》 SCIE 2001年第9期1162-1166,共5页
The composite films of GaSb nanoparticles embedded in SiO2 matrices were fabricated by radio-frequency magnetron co-sputtering. Transmission electron microscope and X-ray diffraction pattern indicate that the GaSb nan... The composite films of GaSb nanoparticles embedded in SiO2 matrices were fabricated by radio-frequency magnetron co-sputtering. Transmission electron microscope and X-ray diffraction pattern indicate that the GaSb nanoparticles were uniformly dispersed in SiO2 matrices. Room temperature transmission spectra exhibit a blue shift of about 2.73 eV. The blue shift increases with decreasing size of GaSb nanoparticles, suggesting the existence of quantum size effects. Room temperature Raman spectra show that there is a larger Raman peak red shift and broadening of the composite films than that of bulk GaSb. This phenomenon is explained by photon confinement effect and tensile stress effect. 展开更多
关键词 GaSb/SiO2 compite films RF magnetron co-sputtering optical properties quantum confinement theory tensile stress effect
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