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multipoint videoconferencing with scalable video coding

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第5期7卷 696-705页

作者： ELEFThERIADIS Alexandros CIVANLAR m.Reha ShAPIRO Ofer Layered media Inc.NJ 07662 USA

We describe a system for multipoint videoconferencing that offers extremely low end-to-end delay, low cost and complexity, and high scalability, alongside standard features associated with high-end solutions such as rate matching and per- sonal video layout. The system accommodates heterogeneous receivers and networks based on the Internet Protocol and relies on scalable video coding to provide a coded representation of a source video signal at multiple temporal and spatial resolutions as well as quality levels. These are represented by distinct bitstream components which are created at each end-user encoder. Depending on the specific conferencing environment, some or all of these components are transmitted to a Scalable Video Conferencing Server (SVCS). The SVCS redirects these components to one or more recipients depending on, e.g., the available network con- ditions and user preferences. The scalable aspect of the video coding technique allows the system to adapt to different network conditions, and also accommodates different end-user requirements (e.g., a user may elect to view another user at a high or low spatial resolution). Performance results concerning flexibility, video quality and delay of the system are presented using the Joint Scalable Video model (JSVm) of the forthcoming SVC (h.264 Annex G) standard, demonstrating that scalable coding outper- forms existing state-of-the-art systems and offers the right platform for building next-generation multipoint videoconferencing systems.

关键词： multipoint videoconferencing, Scalable video coding, multipoint control

Collaborative Supply Chain management: A Critical Redesigning Factor

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厦门大学学报（自然科学版） 2002年第S1期41卷 257-258页

作者： Z m Udin Department of mechanical and medical Engineering

In improving the competitiveness of business organi sa tion in the 21st century, minimising cost and increasing productivity are no lon ger factors that could promise the success. The changes in customer trends whic h focusing more on product or service customising, high quality and short delive ry times are additional crucial factors that organisation should be aware of. T hese factors have direct relations on how the management could utilise the capab ility of its supply chain management (SCm). The importance of SCm in organisati on specifically to manufacturer is to play a vital role in managing the flow of material and information along the chain from suppliers to customers. In a trad itional way, SCm is mainly manage by the production department in organisation b ut with the advancement in information technology, resulted the changes in worki ng environment. One of the ways that could be implemented in decision making p rocess in order to improve the effectiveness and efficiency of the decision is t hrough collaborative environment. Due to this situation, there is a need to rede sign the existing SCm in order to optimise its capability and functionality in t he way to ensure the organisation competitiveness is sustainable. A minor or ma jor alignment to SCm business processes should be done in order to streamline th e flow of information, which could also affect the flow of materials. Factors s uch as SCm operational, structural and even its managerial are among the issues that are critical in redesigning its business process. Each of these factors has its own attributes such as lead-times, complexity, frequency and organisationa l setting that could lead in improving organisational competitiveness. In additi on, by identifying these factors, it would help the management to plan and desig n the collaborative SCm that would effectively correspond to the changes in busi ness and customer trends. The intention of the paper is to promote a list of fa ctors and attr

关键词： SCm A Critical Redesigning Factor Collaborative Supply Chain management

mid-Infrared Lasers With Low Threshold and Photodetectors

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光学学报 2003年第S1期23卷 323-324页

作者： A. Z. Li h. Li Y. G. Zhang X. Zhang Y. L. Zheng G. Y. Xu m. Qi C. Gmachl m. L. Peabody A. Y. Cho State Key Laboratory of Functional materials foe Informatics Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences 865 Changning Rd. Shanghai 200050 China Bell Laboratories Lucent Technologies 600 Mountain Avenue Murray HillNJ 07974 USA

We report the growth, fabrication, and operation of 2.0μm InGaAsSb/AlGaAsSb laser diodes and 8.5μm GaInAs/AlInAs quantum cascade lasers with low threshold current and the latest improvements in the performance of In... 详细信息

关键词： threshold current laser diodes the growth

Optimal finite-dimensional spectral densities for the identification of continuous-time mImO systems

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Control Theory and Technology 2019年第3期17卷 276-296页

作者： I.m.mIThUN Shravan mOhAN Bharath BhIKKAJI Department of Electrical Engineering Indian Institute of Technology Madras Chennai 600036 India

This paper presents a method for designing in puts to identify linear con tinuous-time multiple-input multiple-output (mImO) systems. The goal here is to design a T-optimal band-limited spectrum satisfying certain input/output power constraints. The input power spectral density matrix is parametrized as the productφu(jω)= 1/2h(jω)h^h(jω),where h(jω) is a matrix polynomial. This parametrization transforms the T-optimal cost function and the constraints into a quadratically constrained quadratic program (QCQP). The QCQP turns out to be a non-convex semidefinite program with a rank one constraint. A convex relaxation of the problem is first solved. A rank one solution is constructed from the solution to the relaxed problem. This relaxation admits no gap between its solution and the original non-convex QCQP problem. The constructed rank one solution leads to a spectrum that is optimal. The proposed input design methodology is experimentally validated on a cantilever beam bonded with piezoelectric plates for sensing and actuation. Subspace identification algorithm is used to estimate the system from the input-output data.

关键词： System identification optimal input design fisher information matrix quadratically constrained quadratic program

Surface-type nonvolatile electric memory elements based on organic-on-organic CuPc-h_2Pc heterojunction

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Chinese Physics B 2015年第11期24卷 328-332页

作者： Khasan S.Karimov Zubair Ahmad Farid Touati m.mahroof-Tahir m.muqeet Rehman S.Zameer Abbas Ghulam Ishaq Khan Institute of Engineering Science and Technology Center for Innovative Development of Science and New Technologies Department of Electrical Engineering College of Engineering Qatar University Department of Ch.m.stry and Earth Sciences Qatar University

A novel surface-type nonvolatile electric memory elements based on organic semiconductors CuPc and h2Pc are fabricated by vacuum deposition of the CuPc and h2Pc films on preliminary deposited metallic （Ag and Cu） electrodes. The gap between Ag and Cu electrodes is 3040μm. For the current-voltage （I-V） characteristics the memory effect, switching effect, and negative differential resistance regions are observed. The switching mechanism is attributed to the electric-field-induced charge transfer. As a result the device switches from a low to a high-conductivity state and then back to a low conductivity state if the opposite polarity voltage is applied. The ratio of resistance at the high resistance state to that at the low resistance state is equal to 120-150. Under the switching condition, the electric current increases -- 80-100 times. A comparison between the forward and reverse I-V characteristics shows the presence of rectifying behavior.

关键词： heterojunction nonvolatile memory organic-on-organic CuPc h2Pc

Nonuniform Dependence on the Initial Data for Solutions of Conservation Laws

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Communications on Applied math.m.tics and Computation 2024年第1期6卷 489-500页

作者： John m.holmes Barbara Lee Keyfitz Department of math.m.tics The Ohio State UniversityColumbusOH43210USA

In this paper,we study systems of conservation laws in one space *** prove that for classical solutions in Sobolev spaces h^(s),with s>3/2,the data-to-solution map is not uniformly *** results apply to all nonlinear s... 详细信息

关键词： Conservation laws Data-to-solution map Nonuniform dependence

The supernova remnant CTB 37B and its associated magnetar CXOU J171405.7-381031:evidence for a magnetar-driven remnant

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Research in Astronomy and Astrophysics 2011年第6期11卷 625-630页

作者： J.E.horvath.m.P.Allen Instituto de Astronomia Geofísica e Ciências Atmosféricas-Universidade de So PauloRua do Mato122605508-900 Cidade Universitria So Paulo SPBrazil CEFET So Paulo Rua Pedro Vicente 62501109-010Caninde'So Paulo SPBrazil

We discuss the association between the candidate magnetar CXOU J171405.7-381031 and the supernova remnant CTB *** recent detection of the period derivative of the object allowed an estimation of a young characteristic age of only ～ *** value is too small to be compatible even with the minimum radius of the remnant being ≥ 10 pc,the value corresponding to the lower limit of the estimated distance of 10.2 ± 3.5 kpc,unless the true distance happens to be even smaller than the lower *** argue that a consistent scenario for the remnant＇s origin,in which the latter is powered by the energy injected by a young magnetar,is indeed more accurate to explain the young age,and demonstrates its non-standard（***-driven） nature.

关键词： stars:supernova — stars:neutron

1988年亚美尼亚地震震源复杂性:慢速余滑事件的证据

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世界地震译丛 1996年第5期27卷 39-51页

作者： m.Kikuchi h.Kanamori K.Satake 许康生甘肃省高台地震台

我们利用多重事件的反褐积方法分析了1988年12月7日的亚美尼亚斯皮塔克地震的远震P波和S波,以探讨震源过程。长周期远震体波表现出复杂的波形,比通常看到的同等大小的地震显得更复杂。识别出了两组次级事件,其中一组是最初20s期间的走... 详细信息

我们利用多重事件的反褐积方法分析了1988年12月7日的亚美尼亚斯皮塔克地震的远震P波和S波,以探讨震源过程。长周期远震体波表现出复杂的波形,比通常看到的同等大小的地震显得更复杂。识别出了两组次级事件,其中一组是最初20s期间的走滑事件,另一组是初始破裂之后约30s开始的倾滑事件。所有子事件的张量之和实质上是标量矩为1.47×10^(19)Nm的走滑事件(走向302°、倾角59°、滑动角143°),倾滑事件(走向89°、倾角60°、滑动角88°)的地震矩是5.6×10^(18)Nm,近乎总量的40％,而且与其他具有走滑机制的次事件相比,矩释放速度慢,我们称这种事件为慢速余滑事件。这种慢速余滑事件的机制和由阿拉伯板块与俄罗斯板块之间的大陆碰撞在高加索地区引起的南北压缩为主的现代形变是一致的。结果表明,在一个出现走滑运动和地壳缩短的地方,如南加州大的走滑事件可能伴随着大的逆冲事件,反之亦然。要确定同震形交的图象,在时间、空间和机制上分辨多重事件是十分必要的。

关键词：地震震源余震滑移事件

NUmERICAL SOLUTION OF ThE SCATTERING PROBLEm FOR ACOUSTIC WAVES BY A TWO-SIDED CRACK IN 2-DImENSIONAL SPACE

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Journal of Computational math.m.tics 2011年第2期29卷 141-166页

作者： Jijun Liu P.A. Krutitskii m. Sini Department of math.m.tics Southeast University Nanjing 210096 China Keldysh Institute of Applied math.m.tics Moscow 125047 Russia Johann Radon Institute for Computational and Applied math.m.tics Austrian Academy of Sciences Linz A~40-40 Austria

The wave scattering problem by a crack F in R2 with impedance type boundary is considered. This problem models the diffraction of waves by thin two-sided cylindrical screens. A numerical method for solving the problem is developed. The solution of the problem is represented in the form of the combined angular potential and single-layer potential. The linear integral equations satisfied by the density functions are derived for general parameterized arcs. The weakly singular integrals and the Cauchy singular integral arising in these equations are computed using a highly accurate sch.m. with a truncation error analysis. The advantage of the sch.m. proposed in this paper is, in one hand, the fact that we do not need the analyticity property of the crack and we allow different complex valued surface impedances in both sides of the crack. In the other hand, we avoid the hyper-singular integrals. Numerical implementations showing the validity of the sch.m. are presented.

关键词： Wave scattering Impedance boundary Integral equations Singularity analysis,Numerics.