• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.16 no.10 s.115
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• pp.1024-1035
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• 2006

A three-dimensional (3-D) method of analysis is presented for determining the free vibration frequencies and mode shapes of thick, complete (circumferentially closed), circular rings with an elliptical or circular cross-section. Displacement components $u_r,\;u_\theta\;and\;u_z$ in the radial, circumferential, and axial directions, respectively, are taken to be periodic in ${\theta}$ and in time, and algebraic polynomials in the r and z directions. Potential (strain) and kinetic energies of the circular rings are formulated, and upper bound values of the frequencies are obtained by minimizing the frequencies. As the degree of the polynomials is increased, frequencies converge to the exact values. Convergence to four-digit exactitude is demonstrated for the first five frequencies of the rings. Novel numerical results are presented for the circular rings having an elliptical cross-section based upon 3-D theory. Comparisons are also made between the frequencies from the present 3-D Ritz method and ones obtained from thin and thick ring theories, experiments, and another 3-D method.

• Journal of Advanced Marine Engineering and Technology
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• v.23 no.5
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• pp.702-710
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• 1999

U-shaped bellows are usually used to piping system pressure sensor and controller for refriger-ator. Bellows subjected to internal pressure are designed for the purpose of absorbing deformation. Internal pressure on the convolution sidewall and end collar will be applied to an axial load tend-ing to push the collar away from the convolutions. To find out deformation behavior of bellow sub-jected to internal pressure the axisymmetric shell theory using the finite element method is adopted in this paper. U-shaped bellows can be idealized by series of conical frustum-shaped ele-ments because it is axisymmetric shell structure. The displacements of nodal points due to small increment of force are calculated by the finite element method and the calculated nodal displace-ments are added to r-z cylindrical coordinates of nodal points. The new stiffness matrix of the sys-tem using the new coordinates of nodal points is adopted to calculate the another increments of nodal displacement that is the step by step method is used in this paper. The force required to deflect bellows axially is a function of the dimensions of the bellows and the materials from which they are made. Spring constant is analyzed according to the changing geometric factors of U-shaped bellows. The FEM results were agreed with experiment. Using developed FORTRAN PROGRAM the internal pressure vs. deflection characteristics of a particu-lar bellows can be predicted by input of a few factors.

• Bulletin of the Society of Naval Architects of Korea
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• v.13 no.1
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• pp.11-16
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• 1976

The effect of the bow shape on the ship motion response in longitudinal regular waves of water of finite depth is investigated by employing the strip theory. The two-dimensional hydrodynamic forces(added mass and damping) were calculated by close-fit method for water of finite depth. The models for investigation are U and V bow ship forms of block coefficient 0.8 with constant after body which were used by Yourkov [2] and recently by Kim [3] for their deep water investigations. The following results are obtained by the present numerical experiments. (1) It is confirmed that the damping coefficient of the V-bow ship is greater than that of U-bow ship and in consquence the amplitude of heave and pitch of V-bow ship is smaller than that of U-bow ship among longitudinal regular head waves in water of finite depth (2) The merit of the V-bow ship on the motion damping is more significant in heave than in pitch, and is decreasing with the shallowness of water depth. (3) The change of bow form gives little effect on the wave exciting force and moment compared with the motion responce.

• Sleep Medicine and Psychophysiology
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• v.8 no.1
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• pp.67-71
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• 2001

Independent Component Analysis (ICA) is a blind source separation method using unsupervised learning and mutual information theory created in the late eighties and developed in the nineties. It has already succeeded in separating eye movement artifacts from human scalp EEG recording. Several characteristic sleep waves such as sleep spindle, K-complex, and positive occipital sharp transient of sleep (POSTS) can be recorded during sleep EEG recording. They are used as stage determining factors of sleep staging and might be reflections of unknown neural sources during sleep. We applied the ICA method to sleep EEG for sleep waves separation. Eighteen channel scalp longitudinal bipolar montage was used for the EEG recording. With the sampling rate of 256Hz, digital EEG data were converted into 18 by n matrix which was used as a original data matrix X. Independent source matrix U (18 by n) was obtained by independent component analysis method ($U=W{\timex}X$, where W is an 18 by 18 matrix obtained by ICA procedures). ICA was applied to the original EEG containing sleep spindle, K-complex, and POSTS. Among the 18 independent components, those containing characteristic shape of sleep waves could be identified. Each independent component was reconstructed into original montage by the product of inverse matrix of W (inv(W)) and U. The reconstructed EEG might be a separation of sleep waves without other components of original EEG matrix X. This result (might) demonstrates that characteristic sleep waves may be separated from original EEG of unknown mixed neural origins by the Independent Component Analysis (ICA) method.

• Journal of Sasang Constitutional Medicine
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• v.14 no.3
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• pp.146-152
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• 2002

Purpose Because Taeyangin constitutions are very rare, There are few references about Taeyangin diseases. I suppose to gather basic materials on the case of a diagnosis and treatment on Taeyangin constitution patient. So I want to accomplish the theory of Taeyangin diseases. Methods I studied I patients with sequelae of CVA who were diagnosed by Taeyangin at department of Sasang constitutional Medicine in Kangnam Kyung Hee Oriental Hospital, and then I investigated the Ordinary symptoms as the diagnosis and treatment on a Taeyangin constitution Conclusion & Results To diagnose Taeyangin constitution, It is important to find out one's ordinary symptomes(especially appearance, personality, taste of food, existence of $y{\breve{u}}lk{\breve{u}}k{\cdot}haey{\breve{u}}k$, condition of urine and feces)

• Knowledge Management Research
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• v.11 no.4
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• pp.41-66
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• 2010

This research examines the effect of the relatedness and the gap between Resources and mechanisms on effectiveness of inter-organizational knowledge transfer. According to the literature, there has been a competing theory between two claims; one is that inter-organizational knowledge transfer will be more effective due to the reduction of the transaction cost as the relatedness increases. And the other is that the mutual complementarity of different organizational characteristics will increase synergy. In total, the relatedness and the gap of the Resource and mechanism makes the inverted U-shaped relationship with the inter-organizational knowledge transfer. As the result of empirical analysis about 109 Korean-based Joint Ventures entered country, it shows that the relatedness of parent company's production Resources, learning mechanisms, and coordination mechanisms made the inverted U-shaped relations with the inter-organizational knowledge transfer and the gap of production Resources and adjustment mechanism formed the same relationship. However, the U-shaped relationship has been established in the relatedness of market Resources, but the gap of market Resources and the learning mechanism was not statistically significant. Through this study, I can draw a best conclusion that the inter-organizational knowledge transfer will be more effective when the relatedness and the gap of management resources and mechanisms is in optimal level. However, when it comes to market Resources, it can be inferred that the result could be the opposite because the partner country's market environment would be different.

• Computers and Concrete
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• v.7 no.2
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• pp.159-167
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• 2010

This paper demonstrates numerical techniques for complex large-scale modeling with microplane constitutive theories for reinforced high strength concrete, which for these applications, is defined to be around the 7000 psi (48 MPa) strength as frequently found in protective structural design. Applications involve highly impulsive loads, such as an explosive detonation or impact-penetration event. These capabilities were implemented into the authors' finite element code, ParaAble and the PRONTO 3D code from Sandia National Laboratories. All materials are explicitly modeled with eight-noded hexahedral elements. The concrete is modeled with a microplane constitutive theory, the reinforcing steel is modeled with the Johnson-Cook model, and the high explosive material is modeled with a JWL equation of state and a programmed burn model. Damage evolution, which can be used for erosion of elements and/or for post-analysis examination of damage, is extracted from the microplane predictions and computed by a modified Holmquist-Johnson-Cook approach that relates damage to levels of inelastic strain increment and pressure. Computation is performed with MPI on parallel processors. Several practical analyses demonstrate that large-scale analyses of this type can be reasonably run on large parallel computing systems.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.2
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• pp.32.1-32.1
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• 2018

The galactic warp is almost ubiquitous among disk galaxies and suspected to be an imprint of recent interactions with other galaxies. The detailed evolutionary course, however, is still uncertain due to the lack of observational evidence. To address this issue, we construct a new extensive catalog of 412 conspicuously warped disks at z = 0.01 ~ 0.05, based on SDSS DR7. We classify the warp morphology through a visual inspection from the Zooniverse Project and our new automated scheme for the warp measurement. We find an interesting color difference between S-and U-shaped warps. The U-type warp galaxies exhibits considerable color offset towards blue compared to both the S-type warps and the control sample of un-warped galaxies. The effect is even more pronounced for galaxies (a) with the greater warp amplitude and (b) with lower luminosity. This is the first piece of observational evidence that the S- and U-shaped warps are on different evolutionary phases in terms of not only dynamics but stellar populations as well. We discuss the implications in the context of the warp evolution theory.

• Journal of Korean Medical classics
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• v.5
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• pp.151-199
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• 1992

A study on Bang-Yak-Hap-Py$\breve{u}$n, one of the most widely-known Korean medicine books, has been conducted and the findings are as follows:the political and social background at the end of Yi-dynasty amidst the inflow of western civilization and the aggression of foreign forces can be seen as a historical period of trial, when civilization and independence had to be preserved at the same time, during the period, the social trend was to pursue a rapid practical solution rather than a profound theory. Responding to this trend, simple and easy medical science became to prevailand the representative medicine book of this kind was Bang-Yak-Hap-Py$\breve{u}$n. 1. Bang-Yak-Hap-Py$\breve{u}$n was written comprising the characteristics of simple and easy medical science with a view to popularizing-collection of logics, easy readability, medical science in time, etc. 2. Bang Yak-Hap-Py$\breve{u}$n, rich and grand in content, came out of Dong-$\breve{U}$i-Bo-Gam at the right moment as a pragmatic guide book of Korea medical practice symbolizing Korean spirit. 3. Do-yun Whang whose pen name was Hye-Am was born in Changwon, Kyungnam-do as the 18th descendant of Changwon Whang family. He engaged in medical practice in Seoul and wrote and edited Boo-Bang-Py$\breve{u}$n-Ram. $\breve{U}$i-Jong-Son-Ik, $\breve{U}$i-J$\breve{u}$ng-Son-Ik-Bu-Yeo, $\breve{U}$i-Bang-Whan-Tu, ect. and made his son, Pil-Su follow him and let him edit Bang-Yak-Hap-Py$\breve{u}$n, which put $\breve{U}$i-Bang-Whal-Tu and Son-Ik-Bon-Cho together. 4. The construct of Bang-Yak-Hap-Py$\breve{u}$n can be subdivied into three parts: herbs of 34 classes and 514 kinds were arranged on the upper part and $\breve{U}$i-Bang-Whal-Tu was arranged on the middle end lower part. Such arrangement can be very effective in clinics. 5. Bang-Yak-Hap-Py$\breve{u}$n as a curative book of Korean medical science has been a necessary another ego for many Korean medical practioners. It also played a great role of enhancing Korean oriental medical science to be widely used by Koreans. On the other hand, it produced a side effect of emergence of employed medical practioner who lacked in scholastic aptitude. 6. Tens or newly edited Bang-Yak-Hap-Py$\breve{u}$n have been issued. Among them, Jung-Jeong, Bang-Yak-Hap-py$\breve{u}$n, J$\breve{u}$ng-Mak-Bang-Yak-Hap-Py$\breve{u}$n. By$\breve{u}$n-J$\breve{u}$ng-Bang-Yak-Hap-Py$\breve{u}$n, and By$\breve{u}$n-J$\breve{u}$ng-Bang-Yak-Jung-Jeon have been widely known. Lately, Bang-Yak-Hap-Py$\breve{u}$n which includes more symptoms and remedies or is translated into Korean came out in several kinds. 7. The number of korea classical medicinal books quoted in Bang-Yak-Hap-Py$\breve{u}$n is 68, among which Dong-$\breve{U}$i-Bo-Gam Occupies the top in the list enlisting 69 medicinal treatment. This Shows that Dong-$\breve{U}$i-Bo-Gam gave birth to Bang-Yak-Hap-Py$\breve{u}$n.

• The Journal of the Korea Contents Association
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• v.14 no.4
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• pp.513-521
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• 2014

The purpose of this research is to develope and implement a convergent educational contents based on theoretical background of integrated education using agent based modeling in the ubiquitous learning environment. The structure of this contents consists of three modules that were designed by trans-disciplinary concept and situated learning theory. These three modules are: convergent problem presenting module, resource of knowledge module and learning of agent based modeling and IT tools module. After the satisfaction survey of the implemented content, out of 5 total value, the average value was 3.86 for effectiveness, 4.13 for convenience and 3.86 for design. The result of the survey shows that the users are generally satisfied. By using this u-learning contents, learners can experience and learn how to solve the convergent problem by utilizing IT tools without any limitation of device, time and space. At the same time, the proposal of structural design of contents can be a good guideline to the researchers to develop the convergent educational contents in the future.