309 research outputs found

    Modified Sagnac experiment for measuring travel-time difference between counter-propagating light beams in a uniformly moving fiber

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    A fiber optic conveyor has been developed for investigating the travel-time difference between two counter-propagating light beams in uniformly moving fiber. Our finding is that there is a travel-time difference Δt = 2vΔl/c2 in a fiber segment of length Δl moving with the source and detector at a speed v, whether the segment is moving uniformly or circularly

    Modified Sagnac experiment for measuring travel-time difference between counter-propagating light beams in a uniformly moving fiber

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    A fiber optic conveyor has been developed for investigating the travel-time difference between two counter-propagating light beams in uniformly moving fiber. Our finding is that there is a travel-time difference Deltat=2vDeltal/c^2 in a fiber segment of length Deltal moving with the source and detector at a speed v, whether the segment is moving uniformly or circularly.Comment: 4 pages, including 4 figure

    Method for Ultrasound Vibrometry Using Orthogonal Basis Functions

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    A method for measuring a mechanical property of a subject includes using an ultrasound transducer to apply ultrasonic vibration pulses to a location in a subject in order to induce shear waves at multiple prescribed orthogonal frequencies in the subject. The ultrasound transducer is directed by an excitation signal that is composed of multiple orthogonal basis functions, each having a given frequency component corresponding to the prescribed orthogonal frequencies. The power level of each orthogonal basis function is independently adjustable. The excitation signal can be sparsely sampled, or portions of the excitation signal can be removed in order to improve tissue vibration and to provide for the interleaving ultrasonic vibration and detection pulses. Ultrasonic detection pulses are applied to at least one motion detection point, from which echo signals are received. From the received echo signals, a motion signal is determined, from which mechanical properties of the subject are calculated. Patent No.: US 8,602,994 Date of Patent: Dec 20, 2013 Filed: Mar 9, 2010 Int. Cl.: A61B 8/00 (2006.01); G01H 1/00 (2006.01) U.S. Cl.: 600/438; 73/579 CPC Cl.: G01S 7/52022 (2013.01); A61B 8/485 (2013.01); G01S 15/8952 (2013.01); G01S 7/52036 (2013.01) Field of Search: ;600/437,443 ;702/19,22 ;382/260 ;345/441,501,552 ;73/574,579,587,60

    Generalized Sagnac Effect

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    Experiments were conducted to study light propagation in a light waveguide loop consisting of linearly and circularly moving segments. We found that any segment of the loop contributes to the total phase difference between two counterpropagating light beams in the loop. The contribution is proportional to a product of the moving velocity v and the projection of the segment length Deltal on the moving direction, Deltaphi=4pivDeltal/clambda. It is independent of the type of motion and the refractive index of waveguides. The finding includes the Sagnac effect of rotation as a special case and suggests a new fiber optic sensor for measuring linear motion with nanoscale sensitivity.Comment: 3 pages (including 3 figures

    The Effects of the Correlation of Electric Materials on Forecasting and Stock Control

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    Forecasting and stock control play an important role in the electric companies because outstanding forecasting and stock control increase service level obviously and decrease stock cost effectively. However, the majority of the electric materials are intermittent demand, resulting in poor forecasting and stock control performance. Therefore, exploring the reasons that affect forecasting performance and stock control is necessary. This paper explores the effects of the correlation of intermittent electric materials on forecasting and stock control. First, we divide the correlation into three categories: autocorrelation in demand sizes, autocorrelation in intervals and cross-correlation between demand size and interval. Forecasting by SBA approach and using periodic dynamic inventory strategy (T, S) to control stock, exploring the effects of these three correlations on forecast accuracy, stock cost and service level. The data shows that correlations of electric materials affect their forecasting and stock control, which will help company find more accurate forecast approach and lower the cost of stock in the future

    Traditional Chinese Medicine Zheng in the Era of Evidence-Based Medicine: A Literature Analysis

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    Zheng, which is also called a syndrome or pattern, is the basic unit and a key concept of traditional Chinese medicine (TCM) theory. Zheng can be considered a further stratification of patients when it is integrated with biomedical diagnoses in clinical practice to achieve higher efficacies. In an era of evidence-based medicine, confronted with the vast and increasing volume of TCM data, there is an urgent need to explore these resources effectively using techniques of knowledge discovery in databases. The application of effective data mining in the analysis of multiple extensively integrated databases can supply new information about TCM Zheng research. In this paper, we screened the published literature on TCM Zheng-related studies in the SinoMed and PubMed databases with a novel data mining approach to obtain an overview of the Zheng research landscape in the hope of contributing to a better understanding of TCM Zheng in the era of evidence-based medicine. In our results, contrast was found in Zheng in different studies, and several determinants of Zheng were identified. The data described in this paper can be used to assess Zheng research studies based on the title and certain characteristics of the abstract. These findings will benefit modern TCM Zheng-related studies and guide future Zheng study efforts
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