• Nuclear Engineering and Technology
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• v.20 no.3
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• pp.145-154
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• 1988

This paper is a study on an accurate and computationally efficient method for reconstructing pointwise power distributions from coarse-mesh nodal calculations. The modern nodal codes can calculate global reactor power shapes and criticality very efficiently and accurately. But inherent in the nodal procedures, there is inevitable loss of information on local heterogeneous quantities. In this study, an improved form function method which reflects the exponential transition of the thermal flux near the assembly surface is developed for the reconstruction of the heterogeneous fluxes. Use of the new form function method in several pressurized water reactor (PWR) benchmark problems reduces the maximum errors in the reconstructed thermal flux to those in the reconstructed fast flux. Even for assemblies adjacent to the steel baffle in realistic PWR cores, use of this method also results in improved pointwise power reconstruction.

• Archives of design research
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• v.14
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• pp.245-254
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• 1996

Form and function are not only the most important factors that tell the very essence of design morphology but also the fundamental factors that determine the existence of things. Th -erefore, approaching to the problems of them and the following practical morphological creation are the final goal of solving all the problems of design. Comparing with such importance and significance of the morphology, however there has been no conscious study nor logical achievement but only partial consideration about them. From this viewpoint, the substantial meanings, the intrinsic attributes and the typical patterns of them are inquired systematically and the whole through this study. Also their relations are identified with some appropriate views. As a result of this study, new knowledge base will be cons -tructed, and it will contribute to developing new morphological thinking and method which are especially strengthened these days.

• The Journal of Korean Academy of Prosthodontics
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• v.29 no.1
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• pp.215-232
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• 1991

In this study, oral sensory function in the osseointegrated root form implant-supported prostheses wearers was estimated by measuring occlusal tactile perception threshold of thickness and sensibility threshold against lateral static loading, and comparing with normal dentition subjects and complete denture wearers group. Osseointegrated root form implants seemed to be restored in the sensation to some extent, and so, dental implants restored edentulous patients in a wide meaning. Conclusions were summarized as following. 1. Occlusal tactile perception threshold of thickness was highest in complete denture wearers group, following by implant-supported prostheses wearers group, normal dentition subjects group. 2. In the implant-supported prostheses wearers group, occlusal tactile perception threshold of opposing artificial teeth case was higher than of opposing natural or opposing implantsupported teeth case. 3. Sensibility threshold against lateral loading of complete denture wearers and implantsupported prostheses wearers group was higher than that of normal dentition subject group. 4. In the implant-supported prostheses group, sensibility threshold against lateral loading was not significantly different between upper and lower jaws. 5. In occlusal tactile perception threshold of thickness and sensibility threshold against lateral loading test, there was no regularity among values of each tooth, and no significant difference between anterior and posterior teeth as well.

• Journal of the Korean Institute of Rural Architecture
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• v.10 no.4
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• pp.33-40
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• 2008

This paper aims to clarify the spatial form and functional transition of Korean traditional shop house in Maehwa marketplace, Uljin. The general form of Korean traditional shop house of Maehwa marketplace was the timbered house of the tin roof built in the 1960s. As the scale of a building being comparatively small-scale, building area is $60m^2$ and the yard was mainly made behind the building. When the spatial form of Korean traditional shop house is considered, the composition of 4 by 2 is most. And in the front of a building, the shop is located, and when the back of a building prepares a residence, integration of a sales function and a habitation function is seen. The shop of Korean traditional shop house is converted into living space by change of the function, and the position is the middle of a front of building. This is considered as what inherited the Korean lifestyle. And the last, Although it is not different from the appearance of the shop house of other areas, since there are few grades of the change in comparison, the extension situation of Korean traditional shop house is recognized as an example important for future research.

• Communications of the Korean Mathematical Society
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• v.36 no.3
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• pp.423-445
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• 2021

In this paper, a new form of poly-Genocchi polynomials is defined by means of polylogarithm, namely, the Apostol-type poly-Genocchi polynomials of higher order with parameters a, b and c. Several properties of these polynomials are established including some recurrence relations and explicit formulas, which are used to express these higher order Apostol-type poly-Genocchi polynomials in terms of Stirling numbers of the second kind, Apostol-type Bernoulli and Frobenius polynomials of higher order. Moreover, certain differential identity is obtained that leads this new form of poly-Genocchi polynomials to be classified as Appell polynomials and, consequently, draw more properties using some theorems on Appell polynomials. Furthermore, a symmetrized generalization of this new form of poly-Genocchi polynomials that possesses a double generating function is introduced. Finally, the type 2 Apostolpoly-Genocchi polynomials with parameters a, b and c are defined using the concept of polyexponential function and several identities are derived, two of which show the connections of these polynomials with Stirling numbers of the first kind and the type 2 Apostol-type poly-Bernoulli polynomials.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.4
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• pp.467-474
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• 2018

The purpose of this study is related to automatic hull-form design for ships operating at two speeds. Research was conducted using a series 60 ($C_B=0.6$) ship as a target, which has the most basic ship hull-form. Hull-form development was pursued from the viewpoint of improving resistance performance. In particular, automatic hull-form design for a ship was performed to improve wave resistance, which is closely related to hull-forms. For this purpose, we developed automatic hull-form design software for ships by combining an optimization technique, resistance prediction technique and hull-form modification technique, appling the software developed to a target ship. A sequential quadratic programming method was used for optimization, and a potential-based panel method was used to predict resistance performance. A Gaussian-type modification function was developed and applied to change the ship hull-form. The software developed was used to design a target ship operating at two different speeds, and the performance of the resulting optimized hull was compared with the results of the original hull. In order to verify the validity of the program developed, experimental results obtained in model tests were compared with calculated values by numerical analysis.

• Design Convergence Study
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• v.16 no.6
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• pp.59-74
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• 2017

Louis Sullivan insisted, "Form follows function." Functionality is one of the most fundamental elements for users to use product or space, and "function" in space and architecture has the meaning of the most important factor in determining its form. In this way, from the viewpoint of "Functionalism," the research selected Toyo Ito to see how important elements pursued by Functionalism are related to his forms of creation. Small residential space projects of Toyo Ito from the early 1970s to the present are selected, so that the structure, material and space type of space and architecture can easily grasped and analyzed. Space and architectural structures and surfaces were classified into the characteristics of materials and classified according to the strength of openness of space. As a result, the space and architecture that pursue the function use a method that can maximize the efficiency of the function while excluding the whole decoration in order to highlight the function. The characteristics found in Toyo Ito's small-scale residential space can be defined as the formalization and simplification of the form, the openness of space, and the versatility of each element.

• 한국전산유체공학회:학술대회논문집
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• 2009.11a
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• pp.49-55
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• 2009

This paper evaluates performances of a recently developed divergence-free finite element method based on Hermite interpolated stream functions. Velocity bases are derived from Hermite interpolated stream functions to form divergence-free basis functions. These velocity basis functions constitute a solenoidal function space, and the simple gradient of the Hermite functions constitute an irrotational function space. The incompressible Navier-Stokes equation is orthogonally decomposed into a solenoidal and an irrotational parts, and the decoupled Navier-Stokes equations are projected onto their corresponding spaces to form proper variational formulations. To access accuracy and convergence of the present algorithm, three test problems are selected. They are lid-driven cavity flow, flow over a backward-facing step and buoyancy-driven flow within a square enclosure. Hermite interpolation functions from cubic to quintic are chosen to run the test problems. Numerical results are shown. In all cases it has shown that the present method has performed well in accuracies and convergences. Moreover, the present method does not require an upwinding or a stabilized term.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1987.04a
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• pp.191-195
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• 1987

When a 160QAM receiver in the band of spread spectrum system is interfered with a pseudo-random frequency-hopp-ing signal the interference signal has the form of the pulse amplitude probability density function. Each interfrering pulse amplitude probability density function Each interfering pulse amplitude is dependent upon theprobability density function of hopping frequency and the selectivity characteristic of 16QAM system in this paper the error rate equation of a system performance has been derived in the above condition which are interfrerence form and impulsive noise environmensts. The results of system analysis show us that the system performance is de-graded by impulsive noise and interference power, which improved as the frequency hopping bandsidth increases whit respect to receiver bandwidth

• International Journal of Precision Engineering and Manufacturing
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• v.3 no.4
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• pp.87-93
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• 2002

In this study, basic concepts of magnet were introduced, and dynamic characteristics of magnet coupling were explored. Based on these characteristics, it was proposed how to analyze transverse and torsional vibrations of a spindle system with magnet coupling. Proposed theoretical approaches were applied to a precision power transmission system machined for this study, and the transverse and torsional vibrations were simulated. The force on magnet coupling was shown as a form of nonlinear function of the gap and the eccentricity. Also, the form of torque transmitted by magnet coupling was considered as a sinusoidal function. Main spindle connected to a coupling of a follower part was assumed to be a rigid body. Nonlinear partial differential equation was derived to be as a function of angular displacement. By using the equation, torsional vibration analysis of a spindle system with magnet coupling was performed. Free and forced vibration analyses of a spindle system with magnetic coupling were explored by using FEM.