4,634 research outputs found

    On the Feasibility of Linear Interference Alignment for MIMO Interference Broadcast Channels with Constant Coefficients

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    In this paper, we analyze the feasibility of linear interference alignment (IA) for multi-input-multi-output (MIMO) interference broadcast channel (MIMO-IBC) with constant coefficients. We pose and prove the necessary conditions of linear IA feasibility for general MIMO-IBC. Except for the proper condition, we find another necessary condition to ensure a kind of irreducible interference to be eliminated. We then prove the necessary and sufficient conditions for a special class of MIMO-IBC, where the numbers of antennas are divisible by the number of data streams per user. Since finding an invertible Jacobian matrix is crucial for the sufficiency proof, we first analyze the impact of sparse structure and repeated structure of the Jacobian matrix. Considering that for the MIMO-IBC the sub-matrices of the Jacobian matrix corresponding to the transmit and receive matrices have different repeated structure, we find an invertible Jacobian matrix by constructing the two sub-matrices separately. We show that for the MIMO-IBC where each user has one desired data stream, a proper system is feasible. For symmetric MIMO-IBC, we provide proper but infeasible region of antenna configurations by analyzing the difference between the necessary conditions and the sufficient conditions of linear IA feasibility.Comment: 14 pages, 3 figures, accepted by IEEE Trans. on Signal Processin

    On the Degrees of Freedom of Asymmetric MIMO Interference Broadcast Channels

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    In this paper, we study the degrees of freedom (DoF) of the asymmetric multi-input-multi-output interference broadcast channel (MIMO-IBC). By introducing a notion of connection pattern chain, we generalize the genie chain proposed in [11] to derive and prove the necessary condition of IA feasibility for asymmetric MIMO-IBC, which is denoted as irreducible condition. It is necessary for both linear interference alignment (IA) and asymptotic IA feasibility in MIMO-IBC with arbitrary configurations. In a special class of asymmetric two-cell MIMOIBC, the irreducible condition is proved to be the sufficient and necessary condition for asymptotic IA feasibility, while the combination of proper condition and irreducible condition is proved to the sufficient and necessary condition for linear IA feasibility. From these conditions, we derive the information theoretic maximal DoF per user and the maximal DoF per user achieved by linear IA, and these DoFs are also the DoF per user upper-bounds of asymmetric G-cell MIMO-IBC with asymptotic IA and linear IA, respectively.Comment: 6 pages, 3 figures, submitted to ICC 201

    Quantum Private Comparison: A Review

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    As an important branch of quantum secure multiparty computation, quantum private comparison (QPC) has attracted more and more attention recently. In this paper, according to the quantum implementation mechanism that these protocols used, we divide these protocols into three categories: The quantum cryptography QPC, the superdense coding QPC, and the entanglement swapping QPC. And then, a more in-depth analysis on the research progress, design idea, and substantive characteristics of corresponding QPC categories is carried out, respectively. Finally, the applications of QPC and quantum secure multi-party computation issues are discussed and, in addition, three possible research mainstream directions are pointed out

    Conspicuous Consumption in Committed Relationships: A Signal of Relationship Dissatisfaction by Heterosexual Men

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    Through conspicuous consumption, humans consume luxury goods or services to show off wealth and status. Conspicuous consumption has been considered as an honest signal that could convey the quality of the signaler to potential receivers, which is positively associated with sexual selection and men’s mate attraction goals. Previous research on the function of men’s conspicuous consumption within evolutionary psychology is mainly built upon the assumption that heterosexual men who buy luxuries are single. Little research to date has considered how being in a committed romantic relationship influences men's conspicuous consumption and how it will be interpreted by their female partner. The current dissertation is the first study to date to investigate the relationship between conspicuous consumption and men’s dissatisfaction with a committed romantic relationship. In a Pilot Study and three online experimental studies, the present dissertation examined (1) the perceived motivation of married men’s conspicuous displays from a third-person perspective, including observers of both genders (Chapter II Pilot Study, Chapter III Study 1); (2) if being dissatisfied with a current relationship would increase committed men’s conspicuous purchases for themselves (Chapter IV Study 2); (3) women’s interpretation of their male partners’ increased conspicuous consumption (Chapter V Study 3). Results demonstrated that (1) from a third-person’s perspective, married men with increased (vs. other patterns of) conspicuous consumption for themselves were viewed as having higher mating intentions; (2) from married men’s perspective, with priming of the negative memory, the more frequently they thought of leaving and/or the lower baseline trait satisfaction they had with their current relationship, married men purchased more conspicuous items for themselves; the higher baseline trait satisfaction they had with their current relationship, married men purchased more conspicuous items for their partner; (3) from committed women’s perspective, increased conspicuousness of the consumption increased their suspicion of their partner’s potential infidelity in the past, present, and future, as well as their assessments of their partner’s potential dissatisfaction with the current relationship. The current dissertation provided a detailed framework for illustrating the motivation for and consequences of men’s conspicuous consumption in the context of a committed romantic relationship.PHDPsychologyUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/163281/1/tingtliu_1.pd
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