• Structural Engineering and Mechanics
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• v.58 no.5
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• pp.783-797
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• 2016

Exact solutions for stresses, strains, and displacements of a perforated rectangular plate by an arbitrarily located circular hole subjected to both linearly varying in-plane normal stresses on the two opposite edges and in-plane shear stresses are investigated using the Airy stress function. The hoop stress occurring at the edge of the non-central circular hole are computed and plotted. Stress concentration factors (the maximum non-dimensional hoop stresses) depending on the location and size of the non-central circular hole and the loading condition are tabularized.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.32 no.5
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• pp.374-381
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• 2008

The correlation coefficient method, which was proposed by our research group, is applied to digital particle holography to locate the focal plane of particles. It uses the fact that the correlation coefficient is maximum at the focal plane. The factors influencing this method are discussed with a numerical simulation of holograms. For real holograms, the Wiener filter was proposed to process both recorded holograms and reconstructed images. The application results using the dot array target showed that the Wiener filter is a very effective tool for processing holography-related images. The effects of the dot size and the object distance on the errors in the determination of the focal plane by the correlation coefficient method were investigated by using the calibration target.

• Journal of the Microelectronics and Packaging Society
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• v.6 no.3
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• pp.65-71
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• 1999

The effects of mask materials and etching solutions on the dimensional accuracy of V-groove were studied for the alignment between optoelectronic devices and optical fibers in optical packaging. PECVD nitride, LPCVD nitride, or thermal oxide($SiO_2$) was used as a mask material. The anisotropic etching solution was KOH(40wt%) or the mixture of KOH and IPA. LPCVB nitride has the best etching selectivity and thermal oxide was etched most rapidly in KOH(40wt%) at $85^{\circ}C$ among the mask materials studied here. The V-groove size enlarged than the designed value. This phenomenon was due to the undercutting benearth the mask layer from the etching toward Si (111) plane. The etch rate of (111) plane wart 0.034 - 0.037 $\mu\textrm{m}$/min in KOH(40wt%). This rate was almost same regardless of mask materials. When IPA added to KOH(40wt%), the etch rate of (100) plane and (111) plane decreased, but etching ratio of (100) to (111) plane increased. Consequently, the undercutting phenomenon due to etching toward (111) plane decreased and the size of V-groove could be controlled more accurately.

• Journal of the Korean housing association
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• v.21 no.6
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• pp.43-52
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• 2010

It has applied the design method of face to face dimension, an MC (Modular Coordination) design method, at design steps of an apartment house for standardization of architecture. But It has been still using center line size. A construction limit isn't specific on these center line size, and dead space occurs with excessive gaps as size matching isn't performed well between structural sieve and parts. And above all, measurement before construction isn't to expect standardization, and to increase custom-made furniture. We investigate manufacture of a preferential domestic system kitchen and construction state, and we derive from a problem in viewpoints of standardization for this. And we utilized a reference plane, and we present construction document and design plan in order to solve these problems. And we analyze an effect got by application of the assembly basis aspect that we presented, and we can raise efficiency of standardization of housing and construction industry, and we light ultimately up.

• Korean Journal of Optics and Photonics
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• v.5 no.1
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• pp.60-66
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• 1994

First, the beam waist size of TE$M_{00}$ Nd:YAG laser mode with Positive Branch Unstable Resonator was calculated. and then, the output power, fundamental mode and multimode beam quality factor of PBUR were measured and compared with thouse of reference resonator with plane pallalel mirrors. In characterizing the beam quality, the $M^2$ concept was used. The focusability of laser beam in unstable resonators was discussed with this $M^2$.

• Korean Journal of Materials Research
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• v.22 no.8
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• pp.397-402
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• 2012

Morphological control on hydroxyapatite crystals has attractive prospects in research to clarify the effects of crystal planes on biological performance. Hydrothermal processing is known as a typical type of processing for fabricating well-grown crystals with unique morphology. The purpose of the present study is to examine the feasibility of well-crystallized crystals with oriented structures through hydrothermal treatment of calcite. A single crystal of calcite was applied to hydrothermal treatment in a phosphate solution at $160^{\circ}C$. Rod-shaped hydroxyapatite crystals with micrometer-size were formed on the {100} face of calcite after treatment, while nanometer-sized hydroxyapatite crystals were formed on the (111). The hydroxyapatite crystals formed on each plane were not morphologically changed with increasing treatment periods. An oriented structure of rod-shaped hydroxyapatite was constructed after hydrothermal treatment of {100} planes on the calcite single, while such orientation was not observed on the (111) plane after the treatment. The layer of hydroxyapatite formed on the {100} plane was thicker than that of the (111) plane. The {100} plane of calcite shows a higher reactivity than that of the (111) plane, which results in rapid crystal growth of hydroxyapatite. The difference in the morphology of the formed hydroxyapatite was governed by the reactivity of each crystal plane exposed to the surrounding solution.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2001.05a
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• pp.40-45
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• 2001

Recently, the use of numerical simulation has been increased rapidly because of the development of high performance computer systems. The present study is aimed to investigate flow characteristics of a two-dimensional sharp plane. Unsteady calculation by FDM(Finite Difference Method) based upon SOLA scheme which was performed at $Re=2{\times}10^4$in viscous incompressible flow within a finite domain on the irregular grid formation. Total numbers of irregular grids are $8{\times}10^4$. The minimum grid size is 1/100 of the plane length L which is the representative length. The inclined angles of every objects are $15^{\circ}, \;30^{\circ}\;and\; 45^{\circ}.$ And, the edge angle of the plane is $30^{\circ}.$ This study discussed the flow characteristics in term of the turbulent intensity, vorticity and frequency analysis. Developed flows show that the periodic Karman vortices occur at the back of the plane.

• Transactions of Materials Processing
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• v.11 no.8
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• pp.682-690
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• 2002

The formation of adiabatic shearband in tungsten heavy alloys(WHA) was studied in this investigation. Five prismatic specimens were loaded by high velocity impacts and treated as plane strain problems. To find out the effect of particle's volume ratio, specimens containing 81%, 93% and 97% volume percents of tungsten particles were used. Also the effects of particle's geometry and size on the formation of shearband were studied for 81% volume percent alloys by small size particle model, large size particle model and undulated particle models, and the results were discussed.be used to diagnose the causes of necking and fracture in industrial practice and to investigate whether these defects were caused by material property variation, changes in lubrication, or incorrect press settings. In non-axisymmetric deep drawing, three modes of forming regimes are found: draw, stretch, plane strain. The stretch mode for non-axisymmetric deep drawing could be defined when the major and minor strains are positive. The draw mode could be defined when the major strain is positive and minor strain is negative, and plane strain mode could be defined when the major strain is positive and minor strain is zero. Through experiments the draw mode was shown on the wall and flange are one of a drawn cup, while the plane strain and the stretch mode were on the punch head and the punch corner area respectively, We observed that the punch load of elliptical deep drawing was decreased according to increase of die corner radius and the thickness deformation of minor side was more large than major side.

• Korean Institute of Interior Design Journal
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• v.18 no.3
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• pp.11-19
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• 2009

This research grasped the change of bathroom type, the present status for the residents' bathrooms, the level of satisfaction and preference for the residents' bathrooms, along with the plane of large-size apartment. This research aims to contribute to making the bathroom space to be able to satisfy the residents' desires. A total of 115 samples, acquired via internet survey, were analyzed with the statistical computer program SPSS PC+ 15.0 with the bathroom plane analysis. The results of this research are as follows. 1) As the results of the most representative plane, were divided into total 4 bathroom types, public bathrooms were $3.9-5.29m^2$ couple bathrooms were over than $3.17-8.3m^2$ in the average bathroom area, and there were two in less than $199m^2$ and even three in more than $199m^2$ in the number of bathrooms. 2) Three bathrooms were preferred by the residents who have three bathrooms now and by the younger generation though two bathrooms were preferred by most residents in the bathroom number. Most of the public bathrooms and couple bathrooms were considered to be proper in the bathroom area. 3) The preferred types were different according to each brand in the preference of the bathroom form. This means that to present a new plane figure including various bathroom forms is recommended in planning the bathroom space hereafter, that the bathroom spaces are changing. 4) In the bathroom environment, to present the technical solution through the study for the natural lighting and the sound arresting is required. This research hopes that the results of this research will be able to be used as the basic data to provide the bathroom space equipped with a pleasant environment condition to the residents.

• Journal of the Institute of Electronics and Information Engineers
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• v.49 no.12
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• pp.95-110
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• 2012

The effect of a finite substrate size on the radiation characteristics of a two-element linear E-plane array antenna using microstrip patch antennas is investigated. The average active element pattern characteristics of two-element E-plane array antennas printed on different dielectric constant substrates with various substrate sizes and element spacings are analyzed. Using the average active element pattern, the radiation pattern characteristics of the array antenna versus scan angle is analyzed. The simulation results show that the diffracted fields of surface waves from substrate edges have a significant effect on the radiation characteristics of a 2-element E-plane array antenna. The distance between the center of patch antenna and the substrate edges on the E-plane for the enhancement of radiation characteristics of the array antenna is about $0.35{\lambda}_0$.