746 research outputs found

    Shor-Preskill Type Security-Proofs for Concatenated Bennett-Brassard 1984 Quantum Key Distribution Protocol

    Full text link
    We discuss long code problems in the Bennett-Brassard 1984 (BB84) quantum key distribution protocol and describe how they can be overcome by concatenation of the protocol. Observing that concatenated modified Lo-Chau protocol finally reduces to the concatenated BB84 protocol, we give the unconditional security of the concatenated BB84 protocol.Comment: 4 pages, RevTe

    Design procedure and performance estimation of tidal current power system

    Get PDF
    The demand to secure an alternative resource has been increased recently rather than fossil or nuclear\ud powers. One of the affordable ocean energy is the tidal energy since it is considered as a reliable and predictable power\ud source. The turbine is one of the essential components which can convert the tidal current into the rotational force. The\ud design optimization of turbine can contribute significantly to the performance of system. There are several key aspects\ud in the design of turbine. Also the estimation of the device performance is to be carried out by the proven technologies.\ud This paper introduces the design procedure of the tidal current turbine considering number of blades, shape, sectional\ud profile, diameter, etc. Also the performance evaluations of the system with single and multi-arrangements are discussed

    Correlated Errors in Quantum Error Corrections

    Full text link
    We show that errors are not generated correlatedly provided that quantum bits do not directly interact with (or couple to) each other. Generally, this no-qubits-interaction condition is assumed except for the case where two-qubit gate operation is being performed. In particular, the no-qubits-interaction condition is satisfied in the collective decoherence models. Thus, errors are not correlated in the collective decoherence. Consequently, we can say that current quantum error correcting codes which correct single-qubit-errors will work in most cases including the collective decoherence.Comment: no correction, 3 pages, RevTe

    A Performance Evaluation of Introducing Balanced Scorecard to High-tech Related Industries in Taiwan

    Get PDF
    Balanced Scorecard (BSC) has become the most desirable performance evaluation tool for industries in Taiwan; however, difficulty or bad performance of system introduction has occurred due to an incomplete understanding of the implementation approaches and correct objectives of the BSC system, causing the risk of cost loss. Two domestic high-tech companies in the high-tech related industry were served as the object of study in this research. The contents of four perspectives of the BSC were converted to twenty key performance evaluation indicators in terms of modern business administration as the variables in the research. Based on the DMAIC model, the importance and satisfaction of BSC implementation factors in high-tech related industry are defined first. The performance indices of satisfaction and importance of implementing BSC are standardized by fuzzy methods for evaluation and a performance matrix with the target line and upper and lower performance control lines are established. Management can analyze the performance level and compare the performance indices and matrixes of two companies after introducing BSC according to the coordinates of satisfaction and importance of implementation factors in the matrixes. These two-dimension matrices will then be converted to one-dimension coordinates for cross performance matrices of four quadrants. Next, performance improvement strategies will be devised in accordance with the aspects of the theory of constraints. After carrying out improvement strategies, the cross performance matrix will be constructed to verify the effect and ascertain the factors of bad performance. In this way, improvement strategies can be re-devised and the most appropriate distribution of resources will be made to sustain the optimum state of ability and cost during the process of introducing the BSC system. Requirements for a short period of time and low cost to evaluate the performance of BSC introduction can be met via this simple and convenient evaluation model presented in this research. Resources will be invested to enhance satisfaction for the implementation factors of high importance and low satisfaction. Likewise, resources will be adjusted to reduce the cost of system introduction for the implementation factors of low importance and high satisfaction. As a result, the time efficiency of introducing the BSC system will be promoted effectively

    Controlled order rearrangement encryption for quantum key distribution

    Full text link
    A novel technique is devised to perform orthogonal state quantum key distribution. In this scheme, entangled parts of a quantum information carrier are sent from Alice to Bob through two quantum channels. However before the transmission, the orders of the quantum information carrier in one channel is reordered so that Eve can not steal useful information. At the receiver's end, the order of the quantum information carrier is restored. The order rearrangement operation in both parties is controlled by a prior shared control key which is used repeatedly in a quantum key distribution session.Comment: 5 pages and 2 figure

    A Two-Step Quantum Direct Communication Protocol Using Einstein-Podolsky-Rosen Pair Block

    Full text link
    A protocol for quantum secure direct communication using blocks of EPR pairs is proposed. A set of ordered NN EPR pairs is used as a data block for sending secret message directly. The ordered NN EPR set is divided into two particle sequences, a checking sequence and a message-coding sequence. After transmitting the checking sequence, the two parties of communication check eavesdropping by measuring a fraction of particles randomly chosen, with random choice of two sets of measuring bases. After insuring the security of the quantum channel, the sender, Alice encodes the secret message directly on the message-coding sequence and send them to Bob. By combining the checking and message-coding sequences together, Bob is able to read out the encoded messages directly. The scheme is secure because an eavesdropper cannot get both sequences simultaneously. We also discuss issues in a noisy channel.Comment: 8 pages and 2 figures. To appear in Phys Rev

    Quantum Gambling Using Three Nonorthogonal States

    Full text link
    We provide a quantum gambling protocol using three (symmetric) nonorthogonal states. The bias of the proposed protocol is less than that of previous ones, making it more practical. We show that the proposed scheme is secure against non-entanglement attacks. The security of the proposed scheme against entanglement attacks is shown heuristically.Comment: no essential correction, 4 pages, RevTe

    Branchial FXYD protein expression in response to salinity change and its interaction with Na+/K+-ATPase of the euryhaline teleost Tetraodon nigroviridis

    Get PDF
    Na+/K+-ATPase (NKA) is a ubiquitous membrane-bound protein crucial for teleost osmoregulation. The enzyme is composed of two essential subunits, a catalytic alpha subunit and a glycosylated beta subunit which is responsible for membrane targeting of the enzyme. In mammals, seven FXYD members have been found. FXYD proteins have been identified as the regulatory protein of NKA in mammals and elasmobranchs, it is thus interesting to examine the expression and functions of FXYD protein in the euryhaline teleosts with salinity-dependent changes of gill NKA activity. The present study investigated the expression and distribution of the FXYD protein in gills of seawater (SW)- or freshwater (FW)-acclimated euryhaline pufferfish (Tetraodon nigroviridis). The full-length pufferfish FXYD gene (pFXYD) was confirmed by RT-PCR. pFXYD was found to be expressed in many organs including gills of both SW and FW pufferfish. pFXYD mRNA abundance in gills, determined by real-time PCR, was significantly higher in FW fish than in SW fish. An antiserum raised against a partial amino acid sequence of pFXYD was used for the immunoblots of gill homogenates and a major band at 13 kDa was detected. The relative amounts of pFXYD protein and mRNA in gills of SW and FW pufferfish were identical, but opposite to the expression levels of NKA. Immunofluorescent staining of frozen sections demonstrated that pFXYD was colocalized to NKA-immunoreactive cells in the gill filaments. In addition, interaction between pFXYD and NKA was demonstrated by co-immunoprecipitation. Taken together, salinity-dependent expression of pFXYD protein and NKA, as well as the evidence for their colocalization and interaction in pufferfish gills suggested that pFXYD regulates NKA activity in gills of euryhaline teleosts upon salinity challenge

    Quantum Gambling Using Two Nonorthogonal States

    Get PDF
    We give a (remote) quantum gambling scheme that makes use of the fact that quantum nonorthogonal states cannot be distinguished with certainty. In the proposed scheme, two participants Alice and Bob can be regarded as playing a game of making guesses on identities of quantum states that are in one of two given nonorthogonal states: if Bob makes a correct (an incorrect) guess on the identity of a quantum state that Alice has sent, he wins (loses). It is shown that the proposed scheme is secure against the nonentanglement attack. It can also be shown heuristically that the scheme is secure in the case of the entanglement attack.Comment: no essential correction, 4 pages, RevTe

    Immunolocalization of chloride transporters to gill epithelia of euryhaline teleosts with opposite salinity-induced Na+/K+-ATPase responses

    Get PDF
    Opposite patterns of branchial Na+/K+-ATPase (NKA) responses were found in euryhaline milkfish (Chanos chanos) and pufferfish (Tetraodon nigroviridis) upon salinity challenge. Because the electrochemical gradient established by NKA is thought to be the driving force for transcellular Cl- transport in fish gills, the aim of this study was to explore whether the differential patterns of NKA responses found in milkfish and pufferfish would lead to distinct distribution of Cl- transporters in their gill epithelial cells indicating different Cl- transport mechanisms. In this study, immunolocalization of various Cl- transport proteins, including Na+/K+/2Cl(-) cotransporter (NKCC), cystic fibrosis transmembrane conductance regulator (CFTR), anion exchanger 1 (AE1), and chloride channel 3 (ClC-3), were double stained with NKA, the basolateral marker of branchial mitochondrion-rich cells (MRCs), to reveal the localization of these transporter proteins in gill MRC of FW- or SW-acclimated milkfish and pufferfish. Confocal microscopic observations showed that the localization of these transport proteins in the gill MRCs of the two studied species were similar. However, the number of gill NKA-immunoreactive (IR) cells in milkfish and pufferfish exhibited to vary with environmental salinities. An increase in the number of NKA-IR cells should lead to the elevation of NKA activity in FW milkfish and SW pufferfish. Taken together, the opposite branchial NKA responses observed in milkfish and pufferfish upon salinity challenge could be attributed to alterations in the number of NKA-IR cells. Furthermore, the localization of these Cl- transporters in gill MRCs of the two studied species was identical. It depicted the two studied euryhaline species possess the similar Cl- transport mechanisms in gills
    • …
    corecore