1,503 research outputs found

    AN INVESTIGATION ON THE ERROR OF CALIBRATING EXTERIOR POINTS WITH INTERIOR POINTS

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    This study was to investigate the accuracy of calibrating exterior points with interior points using a frame with the same structure as Peak frame. Two cameras were used. Some points of the frame were used as control points to calibrate others using the DLT method. When we calibrated exterior points with interior points, the minimal and maximal errors were 0.171 cm and 1.797 cm respectively in the horizontal direction (X), 0.213 cm and 4.856 cm in the horizontal direction (Y), 0.103 cm and 1.608 cm in the vertical direction (Z). When we calibrated the interior points with exterior points, almost all errors were less than 1cm. It was concluded that to get the most accurate 3D reconstruction of human movement, it is necessary to make sure that the space formed by control points contains the objects to be calibrated

    Multi-step quantum secure direct communication using multi-particle Green-Horne-Zeilinger state

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    A multi-step quantum secure direct communication protocol using blocks of multi-particle maximally entangled state is proposed. In this protocol, the particles in a Green-Horne-Zeilinger state are sent from Alice to Bob in batches in several steps. It has the advantage of high efficiency and high source capacity.Comment: 4 pages and 1 figure. Revised version of Optics Communications 253 (2005(1

    ANALYSIS OF VALGUS CHARACT,ERISTICS OF OSSEOUS STRUCTURE OF THE FEET WITH THREE-DIMENSIONAL RECONSTRUCTION TECHNIQUES

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    Using the advanced MR images scan technique combined with three-dimensional reconstruction software, the study went deep into the research of feet's osseous tissue structure. After an investigation of 37 sUbjects' 10 indexes including valgus index and rear foot angle, the study showed distinct differences between normal foot and flatfoot. The correlation modulus of the X-ray images of flatfoot with valgus index is 0.75, and the correlation modulus with rear foot angle is 0.29. The phenomenon that most people with flatfeet had anklebone moving outside illuminated ,that flatfoot resulted from monstrosity of the navicular, cuneiform and metatarsus. However, rear foot angle only embodyed the relative position between calcaneus and shankbone. It couldn't explain the structure differences between flatfoot and normal foot

    Quantum dense coding in multiparticle entangled states via local measurements

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    In this paper, we study quantum dense coding between two arbitrarily fixed particles in a (N+2)-particle maximally-entangled states through introducing an auxiliary qubit and carrying out local measurements. It is shown that the transmitted classical information amount through such an entangled quantum channel usually is less than two classical bits. However, the information amount may reach two classical bits of information, and the classical information capacity is independent of the number of the entangled particles in the initial entangled state under certain conditions. The results offer deeper insights to quantum dense coding via quantum channels of multi-particle entangled states.Comment: 3 pages, no figur

    Quantum secure communication scheme with W state

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    Recently, Cao et al. proposed a new quantum secure direct communication scheme using W state. In their scheme, the error rate introduced by an eavesdropper who takes intercept-resend attack, is only 8.3%. Actually, their scheme is just a quantum key distribution scheme because the communication parties first create a shared key and then encrypt the secret message using one-time pad. We then present a quantum secure communication scheme using three-qubit W state. In our scheme, the error rate is raised to 25% and it is not necessary for the present scheme to use alternative measurement or Bell basis measurement. We also show our scheme is unconditionally secure.Comment: Comments are welcom

    A Mixture Model for Random Responding Behavior in Forced-Choice Noncognitive Assessment:Implication and Application in Organizational Research

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    For various reasons, respondents to forced-choice assessments (typically used for noncognitive psychological constructs) may respond randomly to individual items due to indecision or globally due to disengagement. Thus, random responding is a complex source of measurement bias and threatens the reliability of forced-choice assessments, which are essential in high-stakes organizational testing scenarios, such as hiring decisions. The traditional measurement models rely heavily on nonrandom, construct-relevant responses to yield accurate parameter estimates. When survey data contain many random responses, fitting traditional models may deliver biased results, which could attenuate measurement reliability. This study presents a new forced-choice measure-based mixture item response theory model (called M-TCIR) for simultaneously modeling normal and random responses (distinguishing completely and incompletely random). The feasibility of the M-TCIR was investigated via two Monte Carlo simulation studies. In addition, one empirical dataset was analyzed to illustrate the applicability of the M-TCIR in practice. The results revealed that most model parameters were adequately recovered, and the M-TCIR was a viable alternative to model both aberrant and normal responses with high efficiency.</p
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