• Journal of Institute of Control, Robotics and Systems
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• v.4 no.4
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• pp.420-426
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• 1998

It is the purpose of this paper to make a preliminary study on the use of repetitive control to improve velocity accuracy by eliminating repetitive disturbances caused by machining inaccuracies of the axis of rotation location. If the control system can be intelligent enough to compensate for such machining errors, then one may be able to improve the accuracy of the velocity control, or alternatively, one may maintain the same accuracy and relax the machining tolerances required. This could decrease cost significantly. Experiments are performed testing repetitive control methods on a constant speed rolling operation testbed. The experimental results show very substantial decreases in the tracking error of the system. Spectral data of the output motion are given to demonstrate the attenuation of the disturbance frequencies and harmonics, related to the bandwidth being used. It is seen that the simplest form of repetitive control which is very easily implemented, can produce striking improvement in control system performance in such belt drive rolling operations, and the learning can be accomplished in a short time.

• Asian-Australasian Journal of Animal Sciences
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• v.9 no.2
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• pp.195-197
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• 1996

Peking duck embryos incubated for 82 hrs after oviposition, stage 18 to 20(Hamberger and Hamilton, 1951) were transferred into the recipient eggshells and further incubated at $38.0^{\circ}C$ RH(relative humidity) 60 to 70%, with rotation at an angle of $30^{\circ}$ and the frequency of 4 times an hour. The survival rate was 100, 98, 82, 82, 70, 46, 21 and 16%, after the incubation period of 4, 8, 12, 16, 20, 24, 28 and 29 days, respectively. The present result clearly shows that the ex ova culture is possible for the Peking duck just as in the cases of the chicken or the quail. This culture technique could be useful for experimental manipulation of the embryos.

• Journal of Korean Academy of Nursing
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• v.16 no.3
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• pp.31-37
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• 1986

The purpose of this study is to develop a ratio scale measuring organizational charateristics in nursing. 599 staff nurses working at 10 educational hospitals in Seoul were participated during the period from July 1 to July 31, 1985. Subjects were instructed to rate at one to five points likert type scale according to the level of positive characteristics affecting the nursing organizational effectiveness. As a result of factor analysis given to 50 items with varimax rotation and rearrangement on the asis of factor loading 0.3, there are 4 factors consisted of 33 items presented: factor 1 : leadership of head nurses and interaction(11 items) factor 2 : leadership of supervisors and top managers(11 items) factor 3 : interaction with supervisors(5 items) factor 4 : organizational climate(6 items) Reliability of the factors were tested by Cronbach's Alpha, and the result was α=0.67∼0.84 Further studies are needed to identify the relationship between this tool and the effectiveness of various organization in nursing.

• Journal of Astronomy and Space Sciences
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• v.30 no.1
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• pp.33-41
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• 2013

Various features of the existing perturbations in the Earth's spin rotation are investigated for the recent and most reliable data by spectral analysis, filtering, and comparison with idealized model. First, theory of Earth's spin rotational perturbation is briefly re-derived in the Earth-fixed coordinate frame. By spectral windowings, different periodic components of the length of day perturbation are separated, and their characters and excitations are discussed. Different periodic components of polar motion are acquired similarly and described with further discussion of their excitations. Causes of the long time trends of both the length of day and polar motion are discussed. Three possible causes are considered for the newly discovered 490-day period component in the polar motion.

• Proceedings of the KIEE Conference
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• 1990.07a
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• pp.100-105
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• 1990

Associated with the protection and control functions in the substations, a new network scheme based on the IEEE 802.4 is proposed in this paper. This network is designed for supporting 3 data classes: 1st, it includes the highly time-critical data for the fault detection function. 2nd, routine data with a period is to served for monitoring the power status. Finally, it contains the control data which is used for reporting an event about protection or tuning some values related with power status. The way to allocate target_token_rotation timer is provided to guarantee the protection and control activities in the suggested network for the substation.

• Proceedings of the KIEE Conference
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• 2001.04a
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• pp.44-46
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• 2001

This paper describes the use of the PHOENICS CFD package for the simulation of the high-current period of the arcing process in a hybrid rotating arc/auto expansion by interrupter. The operating principle of this device depends on rapid arc rotation due to the magnetic field created by the fault current through a coil which is mounted on contacts and also relies on the principle of thermal expansion created by arc energy in extinguishing chamber and finally causes pressure rise in expansion volume. This paper is divided into three main sections. The first gives a brief overview of the interrupter. The second section gives a full description of the methods used in the calculation. The final section presents some sample results for the hybrid interrupter.

• Structural Engineering and Mechanics
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• v.30 no.4
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• pp.427-444
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• 2008

A mathematical model for the nonlinear dynamics of a rotating beam with flexible root attached to a rotating hub with elastic foundation is developed. The model is developed based on the large planar and flexural deformation theory and the potential energy method to account for axial shortening due to bending deformation. In addition the exact nonlinear curvature is used in the system potential energy. The Lagrangian dynamics and the assumed mode method is used to derive the nonlinear coupled equations of motion hub rotation, beam tip deflection and hub horizontal and vertical displacements. The derived nonlinear model is simulated numerically and the results are presented and discussed for the effect of root flexibility, hub stiffness, torque type, torque period and excitation frequency and amplitude on the dynamic behavior of the rotating beam-hub and on its stability.

• Proceedings of the KIEE Conference
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• 2003.11a
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• pp.297-299
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• 2003

This paper proposes a totally new method in the chaos characteristics analysis of power systems, the introduction of topological invariants. Using a return histogram the bifurcation graph was drawn, the periodic orbits and topological invariants the local crossing number, relative rotation rates, and linking number during the process of period-doubting bifurcation and chaos were extracted. This study also examined the effect on the topological invariants when the sensitive parameters were varied. In addition, the topological invariants of a three-dimensional embedding of the strange attractor was extracted and the result was compared with those obtained from differential equations. This could be a new way for a state detection and fault diagnosis in a dynamical system.

• Journal of Yeungnam Medical Science
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• v.37 no.2
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• pp.84-89
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• 2020

Spinal pain is a common patient complaint in clinical practice. Conservative treatment methods include oral medication, physical therapy, injections, and spinal orthoses. The clinical application of orthoses is debated because of potential complications associated with long-term use, such as muscle weakness and joint contracture. We reviewed the orthoses most frequently used to manage spinal pain. We review the use of soft cervical and Philadelphia collars, lumbosacral corsets, and thoracolumbosacral orthosis to manage spinal pain. Spinal orthoses can help reduce pain by protecting the muscles and joints of the injured spinal region, preventing or correcting malformations, and limiting trunk flexion, extension, lateral flexion, and rotation. The short-term use of spinal orthoses is known to improve pain and disability during the treatment period without significant adverse effects. Spinal orthoses are expected to alleviate pain and improve patients' lifestyle.

• Journal of applied mathematics & informatics
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• v.39 no.5_6
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• pp.859-882
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• 2021

In the proposed paper, a new algorithm based on Nonlinear Feedback Shift Register (NLFSR) and modified RC4A (Rivest Cipher 4A) cipher is introduced. NLFSR is used for image pixel scrambling while modified RC4A algorithm is used for pixel substitution. NLFSR used in this algorithm is of order 27 with maximum period 2^27-1 which was found using Field Programmable Gate Arrays (FPGA), a searching method. Modified RC4A algorithm is the modification of RC4A and is modified by introducing non-linear rotation operator in the Key Scheduling Algorithm (KSA) of RC4A cipher. Analysis of occlusion attack (up to 62.5% pixels), noise (salt and pepper, Poisson) attack and key sensitivity are performed to assess the concreteness of the proposed method. Also, some statistical and security analyses are evaluated on various images of different size to empirically assess the robustness of the proposed scheme.