• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.05a
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• pp.721-724
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• 2000

This paper presents a prediction of tool deflection and resulting machining error fur sculptured surface productions in the ball-end milling process. Due to the different materials and the dimensions of the tool holder and cutter, a cantilever hem model with three uniform sections is proposed fur the tool deflection model. The ability of this model has been verified by a machining experiment. In this study, cutting force and machining error are investigated. This paper provides the prediction of machining error for sculptured surface to improve machining quality for industrial application.

• Korean Journal of Heritage: History & Science
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• v.34
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• pp.80-101
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• 2001

This article is concentrated on the organization for labor exchange in producing hemp cloth at Geumso-ri, Imha-myoun, Andong city. The organization is called "Sam-dool-ge", and it is different from the organization for labor exchange in producing rice because it is managed by women mostly. ln harvesting hemp, same amount of labor and expenses are invested. Especially, labor is supplied in equal condition. In spinning hemp cloth, the work is shared on the basis of same tech level. In threading the warp and fastening hemp cloth. the work conducted collaborately under the best engineer's direction. "Sam-dool-ge", a gil-sam labor exchange, also presents cultural creativity which produces and inherits the folkloric tradition, and also has the quality as a rite of passage. Nowadays, producing hem cloth is for pursuiting of profits than for making clothes as it used to be. This tradition will be lasted at least for a while because some young generations are beginning to participate in and old generation is teaching them good.

• Nuclear Engineering and Technology
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• v.54 no.3
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• pp.834-841
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• 2022

System thermal-hydraulic (STH) code is adopted for nuclear safety analysis. The critical flow model (CFM) is significant for the accuracy of STH simulation. To overcome the defects of current CFMs (low precision or long calculation time), a CFM based on a genetic neural network (GNN) has been developed in this work. To build a powerful model, besides the critical mass flux, the critical pressure and critical quality were also considered in this model, which was seldom considered before. Comparing with the traditional homogeneous equilibrium model (HEM) and the Moody model, the GNN model can predict the critical mass flux with a higher accuracy (approximately 80% of results are within the ±20% error limit); comparing with the Leung model and the Shannak model for critical pressure prediction, the GNN model achieved the best results (more than 80% prediction results within the ±20% error limit). For the critical quality, similar precision is achieved. The GNN-based CFM in this work is meaningful for the STH code CFM development.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.9 no.6
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• pp.630-636
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• 2016

In this paper, a novel triple-mode cavity structure, designed for compactness and operating at 850 MHz, is analyzed. A cylindrical dielectric resonator is loaded into a metallic cylindrical cavity. Previous study has been focused on the analysis of the cylindrical dielectric resonator, but in this paper, the effect of the cylindrical metallic cavity has been analyzed. Enclosing the dielectric resonator inside the metallic cavity increases the resonant frequency of the dielectric resonator; however, this increases the quality factor and introduces the possibility of installing coupling screws. The principle of generation of triple-mode was investigated by parametric analysis. The generated triple-mode is TE011 mode and two orthogonally generated HEM121 modes. By adjusting the radius of the dielectric resonator, the height of the dielectric resonator, or the radius of the cylindrical metallic cavity, three modes could be coincided. However, the height of the metallic cavity keeps three modes separated. The mode characteristics of the proposed cavity are analyzed using a full-wave electromagnetic (EM) simulation. The proposed triple-mode cavity could be developed to triple-mode filter using a coupling screw, and the commercial application for the miniaturized filter below 1 GHz could be expected.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07b
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• pp.1010-1014
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• 2004

High quality GaN layer and $In_xGa_{1-x}N$ alloy were obtained on (0001)sapphire substrate using ammonia$(NH_3)$ and dimethylhydrazine$(DMH_y)$ as a nitrogen source by gas source molecular hem epitaxy(GSMBE) respectively. As a result, RHEED is used to investigate the relaxation processes which take place during the growth of GaN and $In_xGa_{1-x}N$. The full Width at half maximum of the x-ray diffraction(FWHM) rocking curve measured from Plane of GaN has exhibitted as narrow as 8 arcmin. Photoluminescence measurement of GaN and $In_xGa_{1-x}N$ were investigated at room temperature, where the intensity of the band edge emission is much stronger than that of deep level emission. In content of $In_xGa_{1-x}N$ epitaxial layer according to growth condition was investigated.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.2
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• pp.149-157
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• 2004

Implicit finite element analysis of the flat surface-straight edge hemming process is performed by using a commercial code ABAQUS/Standard. Methods of finite element modeling for springback simulation and contact pair definition are discussed. An optimal mesh system is chosen through the error analysis that is based on the smoothing of discontinuity in the state variables. This study has focused on the investigation of the influence of process parameters in flanging, pre-hemming and main hemming on final hem quality, which can be defined by turn-down, warp and roll-in. The parameters adopted in this parametric study are flange length, flange angle, flanging die corner radius, face angle and insertion angle of pre-hemming punch, and over-stroke of pre-hemming and main hemming punches.

• Geophysics and Geophysical Exploration
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• v.14 no.1
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• pp.1-6
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• 2011

As a check on calibration and drift in each discrete sub-system of a commercial frequency-domain airborne electromagnetic system, we aim to use causality constraints alone to predict in-phase from wide-band quadrature data. There are several possible applications of the prediction of in-phase response from quadrature data including: (1) quality control on base level drift, calibration and phase checks; (2) prediction and validation of noise levels in in-phase from quadrature measurements and vice versa and in future; and (3) interpolation and extrapolation of sparsely sampled data enforcing causality and better frequency-domain-time-domain transformations. In practice, using tests on both synthetic and measured Resolve helicopter-borne electromagnetic frequency domain data, in-phase data points could be predicted using a scaled Hilbert transform with a standard deviation between 40 and 80 ppm. However, relative differences between base levels between flight could be resolved to better than 1 ppm, which allows an independent quality control check on the accuracy of drift corrections.

• Food Science and Preservation
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• v.12 no.6
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• pp.565-571
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• 2005

This study was to develope health promoting and better quality of Kochujang. Three kinds of medicinal plants, Angelica acutiloba (AA), Akebia quinate decaisne (AQ), Caragana chamlagu (CC) were extracted with water. Hanbang Kochujang was prepared by adding water extracts of medicinal hem to the ingredients of Kochujang. Quality characteristics of Hanbang Kochujang were evaluated by its water content, color and sensory evaluation during storage at $5^{\circ}C$: and $20^{\circ}C$ for 90 days. Moisture contents of Hanbang Kochujang before storage were $33\~38\%$ and increased to $48\~51\%$ at the end of storage. Color values(L, a and b) of Hanbang Kochujang were decreased as the progress of storage period at $5^{\circ}C$ and $20^{\circ}C$. Redness (a) values of Hannbang Kochujang with Akebia quinate decaisne (KAQ) and Caragana chamlagu (KCC) were lower than that of control Kochujang (KC) during storage at $20^{\circ}C$(p<0.05). Yellowness(b) values of Hannbang Kochujang with Caragana chamlagu (KCC) was lower than that of control Kochujang (KC) during storage at $5^{\circ}C$(p<0.05). From sensory evaluation, preference was higher in Hanbang Kochujang (KAA, KAQ and KCC) stored at $20^{\circ}C$ than that stored at $5^{\circ}C$ during 60 and 90 days of storage. Sensory evaluation scores of color, sweet taste and overall preference were the highest in Hanbang Kochujang added Caragana chamlagu (KCC) during storage at $5^{\circ}C$ and $20^{\circ}C$ for 90 days (p<0.05).

• The Korean Journal of Ecology
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• v.26 no.6
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• pp.297-305
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• 2003

Fish fauna of mountain streams in the Jirisan National Park area of S. Korea (total area: 440.45 $\textrm{km}^2$, height: 1,915 m) was investigated at 33 sites from May 1997 to September 1999. A total of 4,670 individuals of fishes were collected and classified into 30 species and 12 families. Zacco temmincki (relative abundance (RA), 63.9%) was found to be the most abundant inhabitant. Subdominant species were Pungtungia hem (RA 6.2%), Zacco platypus (RA 6.1 %) and Coreoleusiscus splendidus (RA 4.8%). Among the total species, 13 species were identified as the Korean endemic species (7 families, 17.2% of 802 individuals). Dominant Korean endemic species was C. splendidus (relative abundance endemics (RAE), 27.8%). Superiors were Coreoperca heizi (RAE 21.8%) and Liobagrus mediadiposalis (RAE 19.8%). One exotic species (Oncorhynchus mykiss, a site and 5 ind.) and translated species (Hypmesus niponensis, two sites and 174 ind.) were collected in this survey. The proportion of Korean endemic species in the park (43.3%) was higher than the average of Korean Peninsular (25.9%). From this study, we conclude that the Jirisan National Park area in Korea would be very important for fish diversity and conservation, especially for the Korean endemic and endangered species.

• Journal of the Korea Fashion and Costume Design Association
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• v.2 no.2
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• pp.113-136
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• 2000

Problems and improvemental measures for the historical inquiry of TV drama costumes and for the reproduction of them were investigated. For this study, the MBC historical drama 'The way of the Great King' started on march 24 in 1998 and ended on september 26 in 1998 was selected as the subject. The reasons why the drama was selected are as follows. First, the historical background was the time of King Young ＆ drama introduced various kinds of costumes Joungjo, which is the starting era of traditional costumes peculiar to Korea. Second, the based on the historical inquiry of that time. There is a limitation in the process of historical inquiry about the costumes of that time because we don't have enough research data such as relics, remains, references, literary works, pictures, etc. Although, in some cases, exact historical inquiry about the costumes were made, they could not be reproduced in the original forms due to several reasons: the absence of the materials of that time, structural changes including length and size for convenience of action, alterations of the manufacturing method for the reuse, addition of the gorgeous and various olors for the enhancement of image quality, variations in colors according to the actor's character, modulations of the structures and colors by the producer's intention, and the restraints in time and money for manufacturing. In view of these situations, it seems to be difficult for us to settle the problems occurring between the historical inquiry about the traditional costumes and the reproduction of them in drama. However, the costumes presented in historical drama have the meanings to provide informations of that time with TV audience. Therefore I think that it is necessary to narrow the gap between the historical inquiry of TV drama costumes and for the reproduction of hem, First, It should be restrained that each broadcasting stations show the costumes under the similar situations of the same age in different ways. Second, We need to unify the inquiry systems concerning historical drama costumes, In addition to this, it is also necessary for broadcasting stations to establish internet sites of traditional costumes for communication.