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BOREL'S DIRECTIONS AND SHARED VALUES 被引量:1
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作者 张庆彩 《Acta Mathematica Scientia》 SCIE CSCD 2013年第2期471-483,共13页
In this article, we study the problems of Borel's directions of meromorphic func- tions concerning shared values and prove that if two meromorphie functions of infinite order share three distinct values, their Borel... In this article, we study the problems of Borel's directions of meromorphic func- tions concerning shared values and prove that if two meromorphie functions of infinite order share three distinct values, their Borel's directions are same. 展开更多
关键词 Meromorphic function borel's direction shared value angular domain
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Transcranial Direct Current Stimulation: Effects on Motor and Non-Motor Symptoms of Parkinson’s Disease
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作者 Fayda Protásio Carlos Alberto Bezerra Tomaz +3 位作者 Joaquim Brasil-Neto Pedro Brandão Nasser Allam Maria Clotilde Henriques Tavares 《Journal of Behavioral and Brain Science》 2024年第5期135-160,共26页
Introduction: In the last thirty years, brain neuromodulation techniques have been used as an alternative to pharmacological treatment of neurological disorders. Parkinson’s disease (PD) is a neurodegenerative disord... Introduction: In the last thirty years, brain neuromodulation techniques have been used as an alternative to pharmacological treatment of neurological disorders. Parkinson’s disease (PD) is a neurodegenerative disorder leading to bradykinesia, rest tremor, postural changes, and non-motor symptoms such as depression, anxiety, sleep disorders, pain, and cognitive decline that compromises executive functions (EFs), responsible for the orderly execution of behaviors and tasks of daily life and intentional and directed actions. To this date, a few studies with transcranial direct current stimulation (tDCS) have shown beneficial effects in PD patients concerning specific motor and non-motor symptoms, targeting the motor cortex and/or prefrontal regions. Objective: The main objective of this study was to evaluate the effects of left prefrontal tDCS across a broad spectrum of motor and non-motor symptoms of PD using established validated scales. Method: Single-blind randomized clinical trial with 18 volunteers with PD, aged between 45 and 80 years (66.1 ± 9.65), who met inclusion and exclusion criteria. Participants were submitted to assessments of motor and non-motor functions employing psychometric scales and tests to evaluate EFs and were randomly divided into two groups: control (sham stimulation) and experimental (active stimulation). All participants were involved in three separate tDCS sessions. The anode was positioned over the left dorsolateral prefrontal cortex and the cathode over the right supraorbital region, with a direct current intensity of 2 mA, lasting 20 minutes. At the end of the three sessions, all participants were reassessed. Results: Significant effects of tDCS on non-motor functions were observed for cognition (verbal fluency of actions, clock copy test, appointment by visual confrontation, and verbal memory with immediate free recall) and subjective assessment of sleep quality (overall restlessness and discomfort in the arms and legs at night, leg and arm cramps at night and distressing dreams). There was also an improvement in the rate of errors and successes for congruent and incongruent stimuli of the Stroop Test. The beneficial effects on motor function were decreased rigidity, improved gait, and greater agility in the finger-tapping test. Conclusion: Three tDCS sessions showed positive results for participants with PD, producing significant improvements in various motor and non-motor functions, including sleep quality, cognition, and EFs. Additionally, the present results indicate that tDCS neuromodulation of the left dorsolateral prefrontal cortex region is feasible, safe, and provides significant objective benefits for PD patients. 展开更多
关键词 Parkinson’s Disease NEUROMODULATION Transcranial direct Current stimulation—tDCs Movement Disorders MOOD sLEEP COGNITION
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Combinations of Right Half-Plane Mappings and Vertical Strip Mappings Convex in the Vertical Direction
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作者 Yulin Cai Zirun She +1 位作者 Fanji Zeng Lu Huang 《Open Journal of Statistics》 2023年第6期941-954,共14页
In this paper, we explore the linear combinations of right half-plane mappings and vertical strip mappings. We demonstrate that the combinations of these harmonic mappings are convex in the vertical direction provided... In this paper, we explore the linear combinations of right half-plane mappings and vertical strip mappings. We demonstrate that the combinations of these harmonic mappings are convex in the vertical direction provided they are locally univalent and sense-preserving. Furthermore, we extend this analysis to a more general case by setting specific conditions. Additionally, we take some common parameters such as  as the dilatation of these harmonic mappings, and prove the sufficient conditions that their combinations are locally univalent and convex in the vertical direction. Several examples are constructed by the Mathematica software to demonstrate our main results. 展开更多
关键词 Harmonic Mapping Linear Combination Cohn’s Rules directional Convexi-ty
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ON THE BOREL DIRECTION OF K-QUASIMEROMORPHIC MAPPINGS 被引量:3
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作者 杨燕 刘名生 《Acta Mathematica Scientia》 SCIE CSCD 2004年第1期75-82,共8页
For the K-quasimeromorphic mappings, a precise fundamental inequality for the angular domain is established. Prom this, the Borel direction of the K-quasimeromorphic mappings of zero order is derived.
关键词 Quasimeromorphic mapping covering surface borel direction
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THE BOREL DIRECTIONS OF ALGEBROIDAL FUNCTION AND ITS COEFFICIENT FUNCTIONS 被引量:2
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作者 张少华 张晓梅 孙道椿 《Acta Mathematica Scientia》 SCIE CSCD 2014年第2期241-251,共11页
In this article, the relationship between the Borel direction of algebroidal function and its coefficient functions is studied for the first time. To begin with, several theorems of algebroidal functions in unit disk ... In this article, the relationship between the Borel direction of algebroidal function and its coefficient functions is studied for the first time. To begin with, several theorems of algebroidal functions in unit disk are proved. By these theorems, some interesting conclusions are obtained. 展开更多
关键词 Algebroidal function coefficient function borel direction.
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Cell reprogramming therapy for Parkinson’s disease 被引量:5
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作者 Wenjing Dong Shuyi Liu +1 位作者 Shangang Li Zhengbo Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第11期2444-2455,共12页
Parkinson’s disease is typically characterized by the progressive loss of dopaminergic neurons in the substantia nigra pars compacta.Many studies have been performed based on the supplementation of lost dopaminergic ... Parkinson’s disease is typically characterized by the progressive loss of dopaminergic neurons in the substantia nigra pars compacta.Many studies have been performed based on the supplementation of lost dopaminergic neurons to treat Parkinson’s disease.The initial strategy for cell replacement therapy used human fetal ventral midbrain and human embryonic stem cells to treat Parkinson’s disease,which could substantially alleviate the symptoms of Parkinson’s disease in clinical practice.However,ethical issues and tumor formation were limitations of its clinical application.Induced pluripotent stem cells can be acquired without sacrificing human embryos,which eliminates the huge ethical barriers of human stem cell therapy.Another widely considered neuronal regeneration strategy is to directly reprogram fibroblasts and astrocytes into neurons,without the need for intermediate proliferation states,thus avoiding issues of immune rejection and tumor formation.Both induced pluripotent stem cells and direct reprogramming of lineage cells have shown promising results in the treatment of Parkinson’s disease.However,there are also ethical concerns and the risk of tumor formation that need to be addressed.This review highlights the current application status of cell reprogramming in the treatment of Parkinson’s disease,focusing on the use of induced pluripotent stem cells in cell replacement therapy,including preclinical animal models and progress in clinical research.The review also discusses the advancements in direct reprogramming of lineage cells in the treatment of Parkinson’s disease,as well as the controversy surrounding in vivo reprogramming.These findings suggest that cell reprogramming may hold great promise as a potential strategy for treating Parkinson’s disease. 展开更多
关键词 animal models AsTROCYTEs AUTOLOGOUs cell reprogramming cell therapy direct lineage reprogramming dopaminergic neurons induced pluripotent stem cells non-human primates Parkinson’s disease
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ON THE EXISTENCE OF SINGULAR DIRECTIONS OF HOLOMORPHIC MAPS FROM THE UNIT DISK INTO P^n(C) 被引量:3
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作者 涂振汉 张莎莎 《Acta Mathematica Scientia》 SCIE CSCD 2010年第5期1631-1639,共9页
This article proves the existence of Julia directions of value distribution of holomorphic mapping f from the unit disk into the n-dimensional complex projective spacePn(C) under the assumption limsupT(r,f)/log 1/... This article proves the existence of Julia directions of value distribution of holomorphic mapping f from the unit disk into the n-dimensional complex projective spacePn(C) under the assumption limsupT(r,f)/log 1/1-r = +∞ for hypersurfaces in general position. A heuristic principle concerning the existence of Julia directions of holomorphic mappings from the unit disk into Pn(C) is given also. 展开更多
关键词 complex projective spaces holomorphic mapping Julia direction Picard's theorem value distribution theory
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Recording the direct surgeon’s view with an operating microscopic view improves microscopic ophthalmic surgery training
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作者 Masayuki Akimoto Kosei Tomita +1 位作者 Miyo Yoshida Yuki Hama 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第9期1555-1558,共4页
AIM:To establish a recording system with a direct view of the surgeon to supplement video recording under an operating microscope,which lacks information on the movement and position of the surgeon’s hands,and to fac... AIM:To establish a recording system with a direct view of the surgeon to supplement video recording under an operating microscope,which lacks information on the movement and position of the surgeon’s hands,and to facilitate the reproduction of a skilled surgeon’s technique by a surgeon in training.METHODS:A small camera was attached to the operating microscope with a custom adapter.Microscopic surgeon’s view and direct surgeon’s view through this new camera were recorded in the surgical recording system.Both movies were synchronized and analyzed how do surgeons handle the instruments.RESULTS:A small camera attached to the operating microscope allowed the surgeon’s hands motion to be recorded without interfering with the surgeon’s movements.Different surgeons used different methods to manipulate the ultrasound handpiece and the irrigation/aspiration device.Even in the simple paracentesis procedure,different surgeons used different methods.Surgeons-in-training were able to identify and improve their weaknesses by watching synchronized movies of their hand motions and microscopic view.CONCLUSION:Simultaneous recording the surgical field out of the operating microscopic view by a small camera set on the microscope is comprehensive and improves surgeons-in-training understanding and learning surgeries. 展开更多
关键词 operating microscopic view direct surgeon’s view video recording microscopic surgery training
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Global Inverse Optimal Tracking Control of Underactuated Omni-directional Intelligent Navigators (ODINs) 被引量:2
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作者 Khac Duc Do 《Journal of Marine Science and Application》 CSCD 2015年第1期1-13,共13页
This paper presents a design of optimal controllers with respect to a meaningful cost function to force an underactuated omni-directional intelligent navigator (ODIN) under unknown constant environmental loads to tr... This paper presents a design of optimal controllers with respect to a meaningful cost function to force an underactuated omni-directional intelligent navigator (ODIN) under unknown constant environmental loads to track a reference trajectory in two-dimensional space. Motivated by the vehicle's steering practice, the yaw angle regarded as a virtual control plus the surge thrust force are used to force the position of the vehicle to globally track its reference trajectory. The control design is based on several recent results developed for inverse optimal control and stability analysis of nonlinear systems, a new design of bounded disturbance observers, and backstepping and Lyapunov's direct methods. Both state- and output-feedback control designs are addressed. Simulations are included to illustrate the effectiveness of the proposed results. 展开更多
关键词 inverse optimality optimal controller global tracking underactuated omni-directional intelligent navigator (ODIN) Lyapunov's direct method backstepping method
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基于激光吸收光谱的CO/CO_(2)/H_(2)S浓度同步在线测量研究
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作者 张学军 陈勤根 +3 位作者 杨展 邓琴 贺拴玲 彭志敏 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2024年第5期1412-1416,共5页
CO、CO_(2)、H_(2)S是燃煤锅炉炉内气氛重要组成部分,其浓度不仅能够反映燃烧工况,还可作为水冷壁高温腐蚀程度判断依据,因此实现CO、CO_(2)、H_(2)S浓度的准确测量意义重大。首先采用波长调制-直接吸收(WM-DAS)方法结合约40 m长光程Her... CO、CO_(2)、H_(2)S是燃煤锅炉炉内气氛重要组成部分,其浓度不仅能够反映燃烧工况,还可作为水冷壁高温腐蚀程度判断依据,因此实现CO、CO_(2)、H_(2)S浓度的准确测量意义重大。首先采用波长调制-直接吸收(WM-DAS)方法结合约40 m长光程Herriott池,在室温低压下,开展不同CO/CO_(2)浓度配比下三种气体吸收率同步测量实验,结果表明三种气体的吸收率测量值与理论计算值相近,相对误差在6.82%以内,测量结果可靠性较高;然后对不同浓度CO/CO_(2)(0~2000μL·L^(-1))、H_(2)S(0~20μL·L^(-1))进行动态测量,结果表明,测量系统对三种组分浓度变化的响应具有较好的线性度。 展开更多
关键词 波长调制-直接吸收光谱 CO浓度 CO_(2)浓度 H_(2)s浓度 同步测量
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ON A NEW SINGULAR DIRECTION OF QUASIMEROMORPHIC MAPPINGS
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作者 吴昭君 孙道椿 《Acta Mathematica Scientia》 SCIE CSCD 2009年第5期1453-1460,共8页
By applying Ahlfors' theory of covering surface, we establish a fundamental inequality for quasimeromorphic mapping in an angular domain. As an application, we prove the existence of a new singular direction for quas... By applying Ahlfors' theory of covering surface, we establish a fundamental inequality for quasimeromorphic mapping in an angular domain. As an application, we prove the existence of a new singular direction for quasimeromorphic mapping f, namely, a precise S direction, for which the spherical characteristic function S(r, f) is used as a comparison function. 展开更多
关键词 quasimeromorphic function s direction spherical characteristic function covering surface
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EXPERIMENTAL RESEARCH ON DIRECTIONAL SOLIDIFICATION OF Al-4.5wt%Cu ALLOY BY ACRT METHOD
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作者 JIE Wanqi(State Key Laboratory of Solidification Processing,Northwestern Polytechnical University,Xi’an 710072,China) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1996年第1期17-22,共6页
Accelerated crucible rotation technique(ACRT) has been used for the directional solidification of Al-4.5wt% Cu binary alloy.By rotating the crucible at varying rate and direction,forced liquid flows are aroused These ... Accelerated crucible rotation technique(ACRT) has been used for the directional solidification of Al-4.5wt% Cu binary alloy.By rotating the crucible at varying rate and direction,forced liquid flows are aroused These flows include Ekman flow,Couette flow and Spiral Shear flow.Especially,Ekman flow acts directly at the L/S interface,changes diffusion and heat exchange conditions and has strong influences on the morphology of L/S interface.Experimental results show that,compared with normal Bridgman specimens,the solidification region is much narrower and the cell spacing is much smaller in ACRT specimens.These influences become much stronger when the accelerating rate is increased. 展开更多
关键词 accelerated crucible rotation technique(ACRT) Al-4.5wt%Cu directional solidification morphology of L/s interface cell spacing
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Rays’ Change of Directions between Inertial Frames and Stellar Aberration
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作者 Caesar P. Viazminsky Piere K. Vizminiska 《Applied Mathematics》 2015年第9期1553-1562,共10页
The path of a light’s signal is one and the same in the universal space regardless of the inertial frame by which it is identified. However, only one frame can be taken stationary and identified with the universal sp... The path of a light’s signal is one and the same in the universal space regardless of the inertial frame by which it is identified. However, only one frame can be taken stationary and identified with the universal space while all other frames are moving. The direction of the path of a light’s pulse in a moving frame is determined in terms of its direction in the stationary one;the result is utilized to explain stellar aberration and show that the tilted direction in the moving frame depends only on its velocity. The aberration increment vector is introduced and employed to determine the apparent position of a star at each point of the earth orbit. Aberration in an earth satellite relative to the geocentric frame is presented. The direction’s change of a light beam between graded inertial frames promotes explaining aberration in an earth’s satellite in parallel to stellar aberration on earth. 展开更多
关键词 directions CHANGE of Light RAYs sTELLAR ABERRATION ABERRATION in a satellite ABERRATION INCREMENT Graded Inertial Frames
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DIRECTION OF DEVELOPMENT FORNATION'S PETROCHEMICAL PRODUCTS AND TECHNOLOGY
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《China Oil & Gas》 CAS 2001年第1期36-38,共3页
关键词 DOWN direction OF DEVELOPMENT FORNATION’s PETROCHEMICAL PRODUCTs AND TECHNOLOGY THAN OVER
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Thruster direction controlling of assembled spacecraft based on gimbal suspension
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作者 Hongliang Xu Hai Huang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第2期442-448,共7页
The attitude control system design and its control effect are affected considerably by the mass-property parameters of the spacecraft. In the mission of on-orbit servicing, as fuel is expended, or the payloads are add... The attitude control system design and its control effect are affected considerably by the mass-property parameters of the spacecraft. In the mission of on-orbit servicing, as fuel is expended, or the payloads are added or removed, the center of mass will be changed in certain axe; consequently, some thrusters' directions are deviated from the center of mass(CM) in certain plane. The CM of assembled spacecraft estimation and thruster direction control are studied. Firstly, the attitude dynamics of the assembled spacecraft is established based on the Newton-Euler method. Secondly, the estimation can be identified by the least recursive squares algorithm. Then, a scheme to control the thrusters' directions is proposed. By using the gimbal installed at the end of the boom, the angle of the thruster is controlled by driving the gimbal; therefore, thrusters can be directed to the CM again. Finally, numerical simulations are used to verify this scheme. Results of the numerical simulations clearly show that this control scheme is rational and feasible. 展开更多
关键词 on-orbit servicing thruster's direction control assembled spacecraft center of mass(CM) identification
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Technical Panorama and Development Direction of China's Petroleum Industry
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《China Oil & Gas》 CAS 2000年第2期21-23,共3页
关键词 Technical Panorama and Development direction of China’s Petroleum Industry
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Effects of Ca(Y)-Si modifier on interface morphology and solute segregation during directional solidification of an austenite medium Mn steel
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作者 Gaofei Liang Zhenming Xu Jianguo Li 《Journal of University of Science and Technology Beijing》 CSCD 2005年第4期335-339,共5页
The austenite medium Mn steel modified with controlled additions of Ca, Y, Si were directionally solidified using the vertical Bridgman method to study the effects of Ca(Y)-Si modifier on the solid-liquid (S-L) in... The austenite medium Mn steel modified with controlled additions of Ca, Y, Si were directionally solidified using the vertical Bridgman method to study the effects of Ca(Y)-Si modifier on the solid-liquid (S-L) interface morphology and solute segregation. The interface morphology and the C and Mn segregation of the steel directionally solidified at 6.9 μtrn/s were investigated with an image analysis and a scanning electron microscope equipped with energy dispersive X-ray analysis. The 0.5wt% Ca-Si modified steel is solidified with a planar S-L interface. The interface of the 1.0wt% Ca-Si modified steel is similar to that of the 0.5wt% Ca-Si modified steel, but with larger nodes. The 1.5wt% Ca-Si modified steel displays a cellular growth parttern. The S-L interface morphology of the 0.5wt% Ca-Si+1.0wt% Y-Si modified Mn steel appears as dendritic interface, and primary austenite dendrites reveal developed lateral branching at the quenched liquid. In the meantime, the independent austenite colonies are formed ahead of the S-L interface. A mechanism involving constitutional supercooling explains the S-L interface evolution. It depends mainly on the difference in the contents of Ca, Y, and Si ahead of the S-L interface. The segregation of C and Mn ahead of the S-L interface enhanced by the modifiers is observed. 展开更多
关键词 austenite Mn steel modification solid-liquid s-L) interface morphology solute segregation directional solidification
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New Direction for China’s Diplomacy
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《ChinAfrica》 2012年第4期10-11,共2页
China is now experiencing growing pains as its economic strength and international influence are on the rise. In the meantime, the international community has higher expectations of China.
关键词 New direction for China’s Diplomacy
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基于DirectShow的网络视频点播系统的设计与实现 被引量:3
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作者 雷文礼 任新成 +1 位作者 张栋 高瑛 《现代电子技术》 北大核心 2015年第7期31-33,38,共4页
随着计算机技术和Internet日新月异的的发展,宽带VOD视频点播技术因其良好的人机交互性和流媒体传输技术倍受教育、娱乐等行业的青睐。设计了一种基于Direct Show技术的视频点播系统,该系统采用VC编程语言实现,基于C/S架构搭建通信网络... 随着计算机技术和Internet日新月异的的发展,宽带VOD视频点播技术因其良好的人机交互性和流媒体传输技术倍受教育、娱乐等行业的青睐。设计了一种基于Direct Show技术的视频点播系统,该系统采用VC编程语言实现,基于C/S架构搭建通信网络,通过套接字实现多台客户机与服务器间的通信。测试结果表明,系统能够正常运行,视频播放流畅,可以满足网络视频点播的需求。 展开更多
关键词 视频点播 direct sHOW C/s架构 套接字
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Revised quantum direct communication scheme with mutual authentication 被引量:2
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作者 刘文杰 陈汉武 +1 位作者 许娟 刘志昊 《Journal of Southeast University(English Edition)》 EI CAS 2010年第4期532-536,共5页
Based on mutual authentication and dense coding,a novel revised efficient quantum direct communication scheme is proposed.It is composed of two phases:the quantum state distribution process and the direct communicati... Based on mutual authentication and dense coding,a novel revised efficient quantum direct communication scheme is proposed.It is composed of two phases:the quantum state distribution process and the direct communication process.The purpose of the former is to authenticate Trent and users to each other,and let the two legitimate users(Alice and Bob)safely share the Bell states.While the latter aims to make direct communication to transmit a secret message between Alice and Bob.In order to prevent from Eve's eavesdropping as well as to authenticate each other simultaneously,a decoy photon checking technique is applied.Compared with other analogous protocols,the quantum state distribution process is more simple and feasible and the proposed scheme is more efficient;i.e.,the total efficiency is almost 100%.Security analysis shows that the proposed scheme is secure against the eavesdropping attacks,the impersonation attacks,and some special Trent's attacks,including the attacks by using different initial states. 展开更多
关键词 quantum direct communication mutual authentica-tion decoy-photon checking impersonation attack special Trent's attack
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