• 전기의세계
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• v.14 no.1
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• pp.5-12
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• 1965

In the designs of the sensitive electronic devices such as phase sensitive detector, X-ray diffractometer, and neutron diffractometers, we must take into account the geometrical factors in a coil systems and extraneous stray fields. Input wave forms in such a sensitive electronic devices are often altered by the influence of these factors. Since the magnitude of the stray fields is generally very small, this affection may be removed by applying a good shielding but it is not ease to remove the affection from a geometrical factor. This affection must be however calculated by the theoretical methods and analytical solution in the equation of these factors. The fundamental purpose of this paper lie in the theoretical calculations and practical measurements of the geometrical factor in the coil systems, finite solenoid, and four point prove. In the heoretical calculations, the geometrical factors in the coil systems were calculated by applying the elliptic functions and in the contact points were calculated by applying the elliptic functions and in the contact points were calculated by applying the eigen functions and the infinite series. The measurements were carried out by using the sensitive electronic device made from author's design, as shown in the Fig. 9. The result of this work has verified the essential correctness of theoretical investigations and measuring techniques of geometrical factors on the design of sensitive electronic devices. It also has several advantages such that: (1) all the data obtained may give effective data to designer to work on the field of sensitive electronic devices or microelectronic devices, (2) it has evidently explained the characteristics of electrical investigations and physical definition, and has removed the conventional error of geometrical factors in the coil systems and contact points.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.18 no.3
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• pp.291-302
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• 2005

Due to the importance of the parameter in structural response, the uncertain elastic modulus was located at the center of stochastic analysis, where the response variability caused by the uncertain system parameters is pursued. However when we analyze the so-called stochastic systems, as many parameters as possible must be included in the analysis if we want to obtain the response variability that can reach a true one, even in an approximate sense. In this paper, a formulation to determine the statistical behavior of in-plane structures due to multiple uncertain material parameters, i.e., elastic modulus and Poisson's ratio, is suggested. To this end, the polynomial expansion on the coefficients of constitutive matrix is employed. In constructing the modified auto-and cross-correlation functions, use is made of the general equation for n-th moment. For the computational purpose, the infinite series of stochastic sub-stiffness matrices is truncated preserving required accuracy. To demons4rate the validity of the proposed formulation, an exemplary example is analyzed and the results are compared with those obtained by means of classical Monte Carlo simulation, which is based on the local averaging scheme.

• Journal of the Korean earth science society
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• v.34 no.5
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• pp.393-401
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• 2013

Spherical harmonics power spectrum of the geopotential field of Gaussian-bell type on the sphere was investigated using integral formula that is associated with Legendre polynomials. The geopotential field of Gaussian-bell type is defined as a function of sine of angular distance from the bell's center in order to guarantee the continuity on the global domain. Since the integral-formula associated with the Legendre polynomials was represented with infinite series of polynomial, an estimation method was developed to make the procedure computationally efficient while preserving the accuracy. The spherical harmonics power spectrum was shown to vary significantly depending on the scale parameter of the Gaussian bell. Due to the accurate procedure of the new method, the power (degree variance) spanning over orders that were far higher than machine roundoff was well explored. When the scale parameter (or width) of the Gaussian bell is large, the spectrum drops sharply with the total wavenumber. On the other hand, in case of small scale parameter the spectrum tends to be flat, showing very slow decaying with the total wavenumber. The accuracy of the new method was compared with theoretical values for various scale parameters. The new method was found advantageous over discrete numerical methods, such as Gaussian quadrature and Fourier method, in that it can produce the power spectrum with accuracy and computational efficiency for all range of total wavenumber. The results of present study help to determine the allowable maximum scale parameter of the geopotential field when a Gaussian-bell type is adopted as a localized function.

• (The)Study of the Eastern Classic
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• no.33
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• pp.7-29
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• 2008

Jang, Hyeon-Guang is one of the representative natural philosophers of Joseon Korea. This article aims to investigate the meaning of the factors of Xiangshuxue(象數學) contained in his cosmology. Xiangshuxue applies Image(Xiang), Numeral(Shu) and In-Yang to present the distinctions, inter-relations and time-series orders of things. Jang's cosmology, combined with Xiangshuxue, insisted that Li(Principle) is infinite in time and space, the cosmos is finite on the other side. This assures that the moral principle is absolute and eternal. Jang emphasized the book I-ching as the criterion and the model in understanding the nature. This restrained the objectivizm of Shaoyong and made his concept 'natural law' difficult to change itself as the experience and the knowledge expand. None the less, his cosmology is appraised in that it strengthened natural philosophical basis of neo-confucianism and preceded the cosmological investigations since mid-Joseon dynasty.

• Computers and Concrete
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• v.32 no.1
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• pp.99-117
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• 2023

The crack under the influence of the higher intensities of the stresses grows and the structure gets collapsed with the time when the crack length reaches to critical value. Therefore, the fracture behavior of a structure in terms of stress intensity factors (SIF) becomes important to determine the remaining fracture strength and capacity of material and structure for avoiding catastrophic failure, increasing safety and further improvement in the design. The robustness of the method has been demonstrated by comparing the numerical results with analytical and experimental results of some problems. XFEM is used to model cracks and holes in structures and predict their strength and reliability under service conditions. Further, XFEM is extended with a stochastic method for predicting the sensitivity in terms of output COVs and fracture strength in terms of mean values of stress intensity factors (SIFs) of a structure with discontinuities (cracks and holes) under tensile loading condition with input individual and combined randomness in different system parameters. In stochastic technique, the second order perturbation technique (SOPT) has been used for the predicting the fracture behavior of the structures. The stochastic/perturbation technique is also known as Taylor series expansion method and it provides the reliable results if the input randomness is less than twenty percentage. From the present numerical analysis it is observed that, the crack tip near to the hole is under the influence of the stress concentration and the variational effect of the input random parameters on the crack tip in terms of the SIFs are lesser so the COVs are the less sensitive. The COVs of mixed mode SIFs are the most sensitive for the crack angles (α=45° to 90°) for all the values of c₁ and d₁. The plate with the shorter distance between hole and crack is the most sensitive with all the crack angles but the crack tip which is much nearer to the hole has the highest sensitivity.

• Journal of Radiation Protection and Research
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• v.9 no.1
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• pp.33-42
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• 1984

A great variety of nuclear gamma rays emitted from fission and activation products of spent nuclear fuel contains much information that can be elicited without affecting the integrity of the fuel elements. But the extraction of such information from the complex spectrum is difficult and requires computer codes. In the present work, a versatile code 'CAERI' was developed which locates peaks and calculates their areas for X-rays as well as gamma rays using elegant features of some widely used programs for gamma-ray peak fitting. 'CAERI' coded in FORTRAN used infinite series approximation more accurate than other workers various, simple, piecewise series approximations for evaluations of the Voigt function which represents the X-ray peak with non-negligible natural line width. 'CAERI' can handle even a complex multiplet consisting of peaks from X-rays and gamma rays in arbitrary mixture, which one often encounters in the isotopic analysis of heavy elements such as U and Pu. The results of the fitting performed on the test spectra of $^{177m}\;Lu\;{\gamma}-ray\;and\;^{235}U\;K_{\alpha}$X-ray show good agreement with those by previous workers.

• Sim-seong Yeon-gu
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• v.38 no.2
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• pp.239-268
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• 2023

Humanity has faced destruction(chaos) due to catastrophes (Covid-19, war, earthquake) and awaits a new restoration. For civilizations and individuals, creation or creativity is essential to psychic development. Creativity is the driving force that renews an individual when a new stance and attitude of consciousness or a new adaptation to reality is desperately needed in the depth of the human mind. This article is the result of an exploration of the nature and characteristics of creativity presented by a series of four dreams. First, the definition and form of creativity were explored in the context of religion, mythology, and history of Eastern and Western. While Western mythology refers to creation or creativity originating from God, ancient China viewed creativity as expressed through the interaction of yin and yang, the movement of Tao. In East and West, the form of creation is divided into creation from nothing, creation from matter, and creation through dissolution from the matrix, which psychologically suggests that creativity or creation originates from the unconscious, the seedbed of infinite potential and creative power. Next, with insights from the second dream, the characteristics of creativity were discussed. Creativity occurs through transcendent function and 'going beyond the frame of reference,' that is, 'transgressivity.' Third, the nature of creativity was explored as the creativity of the unconscious aims for regeneration and drives the renewal of Self archetypal images within the collective and individuals. Ultimately, the creativity of the unconscious is the goal of the whole psyche and aims for individuation to become the whole. Realizing the creativity of the unconscious is the fate of humans as the second creator.

• The Journal of the Korea Contents Association
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• v.11 no.1
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• pp.134-144
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• 2011

Crossmedia Storytelling is receiving attention as a new style of description in the age of limitless competition and infinite fusion among media. Crossmedia Storytelling specifies a form of storytelling carried out through mixed usage of plural media, such as televisions, movies, and web services. It is different from OSMU strategy in that plays one source of contents according to the characteristics of various media while Crossmedia Storytelling demands users' active participation. Moreover, it is also slightly different from Transmedia Storytelling in the point that narratives of each media are not complete themselves and only through effectively combining plural media can the whole story fully enjoyed. This research aims to analyze how users move among media in terms of Crossmedia contents by examining cases of Swedish interactive drama series , from Australia, and from the United States. To do so, first, the paper looks into the principles of Crossmedia communication and examines that it is based on online word-of-mouth communication, such as viral marketing. As a result, the following was found in the cases of Crossmedia Storytelling: negative stories that arouse users' emotional reactions & users' participation are effective, and the set-up of Sneezer, which causes the knowledge gap, is very important. It was also found that users' participation was actively taking place through online WOM communication in Crossmedia Storytelling.

• The Journal of the Acoustical Society of Korea
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• v.39 no.4
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• pp.270-278
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• 2020

In this paper, sound transmission of Micro-Perforated Plates (MPPs) installed in an impedance tube with a circular cross-section is described using an analytic method. Vibration of the plates is expressed in terms of an infinite series of modal functions, where modal function in the radial direction is given by the Bessel function. Under the plane wave assumption, a low frequency approximation is derived, and a formula for the sound transmission coefficient of multi-layered MPPs is presented using the transfer matrix method. The Sound Transmission Losses (STLs) of single and double MPPs are computed using the proposed method and compared with those done by the Finite Element Method (FEM), which shows an excellent agreement. As the perforation increases, the STL is degraded, since the STL becomes dominated by the perforation ratio rather than by vibration of the plate. The STL shows dips at natural frequencies as well as at the mass-spring-mass resonance frequency. The proposed model for the STL prediction in this study can be applied to an arbitrary number of MPPs, where each MPP may or may not have a perforation.

• Journal of the Korea Institute of Military Science and Technology
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• v.20 no.6
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• pp.752-757
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• 2017

Analysis has been performed for the penetration of a long-rod into MMC/Ceramic layered armour system with several shot test and a series of simulations. Two types of MMC plate have been fabricated by a liquid pressing method; A356/45%vol.%SiCp with a uniform distribution of SiC particle and Al7075/45%vol.B4Cp with B4C particle. The mechanical properties were measured with the high-speed split Hopkins bar test, hardness test and compression test. The popular Simplified Johnson-Cook model was adopted to represent the material characteristics for FEM simulations. The performance of the MMC applied armour system has been made by comparing with the semi-infinite mild steel target using the depth of penetration(DOP). The results show that placing ceramic front layer provides a certain gain in protection, and that placing another ductile front layer provides a further gain. The application of MMC is found to be attractive.