• Steel and Composite Structures
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• v.35 no.4
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• pp.555-566
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• 2020

This paper aims to present an analytical methodology to investigate influences of nanoscale and surface energy on buckling stability behavior of perforated nanobeam structural element, for the first time. The surface energy effect is exploited to consider the free energy on the surface of nanobeam by using Gurtin-Murdoch surface elasticity theory. Thin and thick beams are considered by using both classical beam of Euler and first order shear deformation of Timoshenko theories, respectively. Equivalent geometrical constant of regularly squared perforated beam are presented in simplified form. Problem formulation of nanostructure beam including surface energies is derived in detail. Explicit analytical solution for nanoscale beams are developed for both beam theories to evaluate the surface stress effects and size-dependent nanoscale on the critical buckling loads. The closed form solution is confirmed and proven by comparing the obtained results with previous works. Parametric studies are achieved to demonstrate impacts of beam filling ratio, the number of hole rows, surface material characteristics, beam slenderness ratio, boundary conditions as well as loading conditions on the non-classical buckling of perforated nanobeams in incidence of surface effects. It is found that, the surface residual stress has more significant effect on the critical buckling loads with the corresponding effect of the surface elasticity. The proposed model can be used as benchmarks in designing, analysis and manufacturing of perforated nanobeams.

• 한국지구물리탐사학회:학술대회논문집
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• 2007.06a
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• pp.130-134
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• 2007

Classical full waveform inversion for velocity estimation defines the objective function as the $l^2$ -norm of differences between the modeled and the observed wavefields. Although widely used, the results of this method have been less than satisfactory. A moderate improvement of this method is to define the objective function as the $l^2$ -norm of differences between the logarithms of the modeled and observed wavefields. In this paper we propose new objective functions of waveform inversion. They produce better results in sub-salt imaging than those of the classical and the logarithmic objective functions. One objective function defines the residual as the difference between $L^{th}$ power of the modeled wavefields and that of the observed wavefields. Another defines the residual as the difference between the integral of the $L^{th}$ power of the modeled wavefields and that of the observed wavefields. We apply these new objective functions to the synthetic SEG/EAGE salt model, and show that our new waveform inversion algorithms provide more accurate results than those of the classical and logarithmic waveform inversion methods.

• The Journal of Korean Medical History
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• v.33 no.2
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• pp.89-104
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• 2020

The purpose of this research is to build a database structure that can be useful for evidence-based medical practices by constructing the knowledge related to oriental medicine in the classical literature knowledge in a form that can utilize new forms of information technology. As a method, "database" is used as a keyword to search published studies in the field of oriental medicine, research is conducted on classic literature knowledge, and studies describing the contents of the data structure are found and analyzed. In conclusion, the original text DB for the preservation of the original texts and the presentation of the supporting texts should include 'Contents Text', 'Tree Structure', 'Herbal Structure', 'Medicine Manufacture', and 'Disease Structure' tables. In order to search, calculate, and automatically extract expressions written in the original text of the old literature, the tool DB should include 'Unit List', 'Capacity Notation List', 'CUI', 'LUI', and 'SUI' tables. In addition, In order to manage integrated knowledge such as herbal, medicine, acupuncture, disease, and literature, and to implement a search function such as comparison of similarity of control composition, the knowledge DB must contain 'dose-controlled medicine name', 'dose-controlled medicine composition', 'relational knowledge', 'knowledge structure', and 'computational knowledge' tables.

• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.237-240
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• 2015

Classical novae (CNe) are interacting binary systems whose outbursts are powered by a thermonuclear runaway in accreted material onto the surface of a white dwarf (WD). The secondary star in such systems fills its Roche lobe and material is transferred onto the WD primary star via an accretion disk. Recurrent novae (RNe) show many similarities to CNe, but have had more than one recorded outburst. RNe play an important role as one of the suspected progenitor systems of Type Ia supernovae, which are used as primary distance indicators in cosmology. Thus, it is important to investigate the nature of their central binary systems to determine the relation between the parameters of the central system and the outburst type, and finally ascertain the population of novae that might be available to give rise to the progenitors of Type Ia SNe. A low outburst amplitude is adopted as a criterion that may help distinguish RNe from CNe and was therefore used to select targets for observations from ground-based observatories including the Liverpool Telescope and the Southern African Large Telescope as well as the full-sky space-based archive of the Solar Mass Ejection Imager (SMEI). We found that at least four objects currently classified as CNe are possibly RNe candidates based on their quiescent spectra. We also searched the SMEI archive for additional outbursts of bright CNe that might otherwise have been missed but did not find a conclusive example.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.8 no.12
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• pp.65-77
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• 1985

The mainpoints of General Theory is 1) the mainspring of economic activity is effective demand which can expand or control in relation to supply as a result of spontaneous decision by customer or government. 2) change in effective demand Produce change in output and employment in the same direction 3) which given productivity of labour the Vice level depend on the money supply affect the in downward direction 4) change in the money supply affect the economy through the rates of interest 5) the only automatic mechanism through which the economy can adjust itself to a deficiency of effective demand is the long process which unemployment reduces wage rates and consequently the demand for money and interest rates, above summarized contents are General Theory frame-work. The neo-classical macro general equilibrium theory, which has been reconstructed subsequent to Keyneses critism is treated the neo-classical macro-general equilibrium theory which inherits the classical theories of labour market and the aggregate production function, on demand side, it introduce the Keyneses macro-general equilibrium theory, which function through flexible movement of prices, wage and interest. Nowadays, Keynes General Theory is being developed into new dimension i, e. the macro-disequilibrium theory, and adequacy, and appropriateness of the theory and its significant contributions to modern economics are being reinterpreted and substantiated.

• Korean Journal of Acupuncture
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• v.25 no.4
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• pp.49-58
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• 2008

Objectives and Methods : The present study was to investigate the change of acupuncture point location of gallbladder meridian in head by way of reviewing classical literatures. Result and Conclusions : 1. The locations of acupuncture points closed-by anatomical marks such as GB1, GB2, GB3, GB11, GB12, GB19, GB20 are clear and accurate. 2. The expression of acupuncture points' locations of GB4, GB5, GB6, GB8 and GB10 are obscure in classical literature, but their locations became clear and objective in recent literatures. 3. The locations of GB9 and GB13 are open to dispute but WHO standard acupuncture point seems to be resonable. 4. In classical literature, the length from the midpoint of the anterior hairline to the midpoint of the posterior hairline is 12 B-cun, and the length from the midpoint of the anterior hairline to the GB19 is 5 cun, 5.5 cun or 6.5 cun. We presume that the length from GB15 to GB19 might have been measured by F-cun.

• Journal of the Korean Institute of Landscape Architecture
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• v.34 no.1 s.114
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• pp.59-68
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• 2006

This paper examines the conceptual shift of wilderness and its legacy to the contradictory view of nature in landscape architecture tradition. In hunting and gathering societies, there was no dichotomy between the cultivated environment and wilderness. 'Wilderness' is a word whose first usage marks the transition from a hunting-gathering economy to an agricultural society. We can identify two archetypal responses to wilderness: classical and romantic. In the classical perspective, wilderness is something to be feared-an area of waste and desolation. The conquest of wilderness and the creation of usable places is a mark of civilization. For the romantics, in contrast, untouched wilderness has the greatest significance; it has a purity that human contact tends to sully and degrade. Wilderness for the romantics is a place to revere, a place of deep spiritual significance, and an object of aesthetic experience. In the Western world, the classical position predominated until the last two hundred years when the romantic concept began to gain more ground. The shift was made possible by the change in the way nature is understood. Modernity and modern science objectified nature. The transition of the concept of wilderness exemplifies the objectification and pictorialization of nature. Wilderness in the modern era is not different from the pastoral landscape which can be controlled by landscape architects.

• The Journal of Internal Korean Medicine
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• v.22 no.3
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• pp.443-452
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• 2001

A migraine is a recurrent, throbbing headache generally felt on one side of the head. Migraines usually begin in early childhood, adolescence, or young adult life. Its accurate pathogenesis is still unknown but migraines are caused by a rapid widening and narrowing of blood vessel walls in the brain and head. The classic migraine and the common migraine are the two main types. The onset of classical migraine may be signalled by visual disturbances in what is called the 'aura' stage. Visual aura is most common among the auras of classical migraine. Common migraine (or migraine without aura) and classical migraine may be accompanied by various combinations of symptoms such as nausea, vomiting, and sensitivity to light and sound. Recently we have exprienced 2 cases of migraine patients and whose conditions were improved through trigger point needling and Oriental medical treatment.

• Journal of the Korean Society for Nondestructive Testing
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• v.30 no.3
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• pp.181-193
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• 2010

The paper presents an alternative way to classical stereocorrelation. First, 2D image processing of random patterns is described. Sub-pixel displacements are determined using phase analysis. Then distortion evaluation is presented. The distortion is identified without any assumption on the lens model because of the use of a grid technique approach. Last, shape measurement and shape variation is caught by fringe projection. Analysis is based on two pin-hole assumptions for the video-projector and the camera. Then, fringe projection is coupled to in-plane displacement to give rise to 3D measurement set-up. Metrological characterization shows a resolution comparable to classical (stereo) correlation technique ($1/100^{th}$ pixel). Spatial resolution seems to be an advantage of the method, because of the use of temporal phase stepping (shape measurement, 1 pixel) and windowed Fourier transform (in plane displacements measurement, 9 pixels). Two examples are given. First one is the study of skin properties; second one is a study on leather fabric. In both cases, results are convincing, and have been exploited to give mechanical interpretation.

• Journal of the Korean Society of Industry Convergence
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• v.9 no.2
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• pp.123-131
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• 2006

The subject of this study is to find out the characteristics of spacial expression in 'Le Carceri' of Giovannibattista Piranesi. Piranesi was the classicist from using classical motif. But for using itself he was not absolute canon of classical but playing tool. Because his etchings of perspective were presented the modernity not fixed the frame. The etchings of Le Carceri were characterized the dark, deep, heavy and devastating. In conclusion, the characteristics of spacial composition in his etchings were presented the simultaneity of time both classic and contemporary time. And it could represented the nonexistent of structurality for visual rationality. Architectural & de-architectural elements of his drawing were become in fragments. So the fragmented elements, his etchings have shawn the off-center to cast off the classical concept. And also the body of human was become the thing of object in his drawing. That is, it was inverted the subject and the object and the function of prison depicted in canvas is disappeared. This is the point of evocation in Piranesi' idea.