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91.
Quantum key distribution transmitter chip based on hybrid-integration of silica and lithium niobates 下载免费PDF全文
A quantum key distribution transmitter chip based on hybrid-integration of silica planar light-wave circuit (PLC) and lithium niobates (LN) modulator PLC is presented. The silica part consists of a tunable directional coupler and 400-ps delay line, and the LN part is made up of a Y-branch, with electro-optic modulators on both arms. The two parts are facet-coupled to form an asymmetric Mach-Zehnder interferometer. We successfully encode and decode four BB84 states at 156.25-MHz repetition rate. Fast phase-encoding of 0 or $\pi $ is achieved, with interference fringe visibilities 78.53% and 82.68% for states $|+\rangle$ and $|-\rangle$, respectively. With the aid of an extra off-chip LN intensity modulator, two time-bin states are prepared and the extinction ratios are 18.65 dB and 15.46 dB for states $|0\rangle$ and $|1\rangle$, respectively. 相似文献
92.
Laura Scrimali 《Applied Mathematics Letters》2012,25(3):385-392
In this paper, we show how one of the Kyoto Protocol mechanisms, the so-called joint implementation in environmental projects, can be transformed into and studied as an infinite-dimensional quasi-variational inequality. Specifically, we examine the situation in which different countries attempt to fulfill Kyoto commitments by investing in emission reduction or emission removal projects in countries where the abatement costs are lower. We derive the equilibrium conditions and prove their characterization in terms of an infinite-dimensional quasi-variational inequality problem. Finally, we discuss the existence of solutions. 相似文献
93.
HAN Lian-Fang CHEN Yue-Ming YUAN Hao 《理论物理通讯》2009,51(4):648-652
We propose a deterministic quantum secure direct two check photon sequences are used to check the securities of the communication protocol by using dense coding. The channels between the message sender and the receiver. The continuous variable operations instead of the usual discrete unitary operations are performed on the travel photons so that the security of the present protocol can be enhanced. Therefore some specific attacks such as denial-of-service attack, intercept-measure-resend attack and invisible photon attack can be prevented in ideal quantum channel. In addition, the scheme is still secure in noise channel. Furthurmore, this protocol has the advantage of high capacity and can be realized in the experiment. 相似文献
94.
异构IP网络中的拓扑自动搜索算法 总被引:3,自引:2,他引:1
针对异构IP网络的拓扑结构建立了网络管理的对象模型,并在此基础上提出了在管理域中实现拓扑逻辑连接和物理连接自动搜索的算法,其中对交换域内物理连接的搜索算法弥补了当前网络管理平台仅提供逻辑连接拓扑图的不足,算法以定理及伪码的形式阐述,并给出了关键的数据结构,试验结果表明,该算法参高效,准确地生成异构IP网络的拓扑图,为智能化的网络故障和性能管理奠定了基础。 相似文献
95.
96.
Intracellular transport of chloride by members of the CLC transporter family involves a coupled exchange between a Cl− anion and a proton (H+), which makes the transport function dependent on ambient pH. Transport activity peaks at pH 4.5 and stalls at neutral pH. However, a structure of the WT protein at acidic pH is not available, making it difficult to assess the global conformational rearrangements that support a pH-dependent gating mechanism. To enable modeling of the CLC-ec1 dimer at acidic pH, we have applied molecular dynamics simulations (MD) featuring a new force field modification scheme—termed an Equilibrium constant pH approach (ECpH). The ECpH method utilizes linear interpolation between the force field parameters of protonated and deprotonated states of titratable residues to achieve a representation of pH-dependence in a narrow range of physiological pH values. Simulations of the CLC-ec1 dimer at neutral and acidic pH comparing ECpH-MD to canonical MD, in which the pH-dependent protonation is represented by a binary scheme, substantiates the better agreement of the conformational changes and the final model with experimental data from NMR, cross-link and AFM studies, and reveals structural elements that support the gate-opening at pH 4.5, including the key glutamates Gluin and Gluex. 相似文献
97.
Madasu Madhu Sai Reddy Doda Prem Kumar Begari Krishna Rao Dasari Gangadhar Thalari Sudhakar Kadari Jhillu Singh Yadav 《Journal of heterocyclic chemistry》2021,58(4):942-946
Enantioselective and a highly concise total synthesis of Ambrisentan are described. The chiral auxiliary controlled enantioselective epoxidation (Azerad protocol), photochemical regioselective epoxide opening, and base mediated ester hydrolysis reactions are the key reactions. 相似文献
98.
Subhash Kak 《Foundations of Physics Letters》2006,19(3):293-296
We present a three-stage quantum cryptographic protocol based on public key cryptography in which each party uses its own
secret key. Unlike the BB84 protocol, where the qubits are transmitted in only one direction and classical information exchanged
thereafter, the communication in the proposed protocol remains quantum in each stage. A related system of key distribution
is also described. 相似文献
99.
We analyze a discrete-time, single-server queueing system in which the length of each service period is limited. The server takes a vacation when the limit expires or the queue empties, whichever occurs first. In the former case, the preempted service is resumed after the vacation without loss or creation of any work. This system models the transmission of message frames from a station on timed-token local-area networks (for example, FDDI and IEEE 802.4 token bus). We study the process of the unfinished work and the joint process of the queue size and the remaining service time. By using the technique of discrete Fourier transforms to determine some unknown functions in the governing equations, we numerically obtain exact mean waiting times.A part of the work of H. Takagi was done while he was with IBM Research, Tokyo Research Laboratory. 相似文献
100.
In this paper, we disclose the synthesis of the dioxabicyclo[3.2.1]octane subunit of the potent antibiotic sorangicin A. The synthesis was achieved in a convergent manner in 8 steps. Regio- and stereoselective intermolecular epoxide opening, ring-closing metathesis and iodo-etherification are key steps. cis-2-Butene diol has been employed as a common staring material. 相似文献