• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.785-788
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• 2006

This paper investigates the temperature history of slab mock-up specimens with various surface curing sheets, in order to determine a favorable surface curing method in hot weather condition. Test showed that insulating double bubble sheets+aluminum foil simultaneously on the upper section of a specimen prevented an increase of sudden temperature and a decrease of vaporization when placed during the hot weather condition. It also secured the high strength in early age. Therefore it is found that using the double bubble sheets+aluminum foil on concrete surface declined the plastic and drying shrinkage and inclined the early strength, thus improving the concrete quality.

• Journal of the Korean Society of Clothing and Textiles
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• v.15 no.2 s.38
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• pp.151-162
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• 1991

The purpose of this study was to examine the point at issue unfitness and unclassification in figures for clothing construction. Comparing measurements of 3 sold figures and physical body by Suck·Go method and 19 items were selected. These items were acquired by factor analysis and cluster analysis an measurements of 200 women in twenties. The results were as follows; 1. Comparison between measurement of figures and physical body; There was not so much difference among figures, but significant difference between figures and physical body. 2. Comparison between measurement of surface area of figures and physical body; There was similar to each figure, but significant difference between figures and physical body. Mostly, figures were bigger than physical body in front parts but smaller in back parts. 3. There were 8 items selected by factor analysis; That is bust girth, waist girth, hip girth, neck base girth, posterior waist length, bust point length, chest breadth and armscye girth. 4. There were 7 clusters selected by cluster analysis.

• Journal of Institute of Control, Robotics and Systems
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• v.3 no.2
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• pp.204-213
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• 1997

In this paper, an application of fuzzy-neuron reasoning to the control of an activated sludge plant is presented. The activated sludge process is widely used in modern wastewater treatment plants. The operation control of the activated sludge process, however, is difficult due to the following reasons : 1)The complexity of the wastewater components, 2)the change of the wastewater influent, and 3)the adjustment errors in the control process. Because of these reasons, it is difficult to obtain mathematical model that really reflect the relationship between the variables and parameters in the process of wastewater treatment correctively and effectively. In this paper, the activated sludge process(A.S.P.) is modeled by a new fuzzy-neuron network representing nonlinear characteristics. These fuzzy-neurons have fuzzy rules with complementary membership function. Based on the constructed model, graphic simulator on X-window system as a graphic integrated environment is implemented. The efficacy of the proposed control scheme was evaluated and demonstrated by means of the field test.

• Korean Journal of Food Science and Technology
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• v.20 no.1
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• pp.59-62
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• 1988

The correlations of rice properties and the texture characteristics of hot($70^{\circ}C$) and cold($20^{\circ}C$) cooked rice were investigated with Japonica and J/Indica rice each of 6 varieties. No significant differences in textural properties between Japonica and J/Indica cooked rices were observed. The hardness of cold cooked rice was positively correlated with setback(r=0.613) of rice flour but not correlated with amylose content and the other chemical properties of starch or rice flour.

• Restorative Dentistry and Endodontics
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• v.16 no.2
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• pp.118-125
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• 1991

Eighty - eight recently extracted teeth were used to evaluate the leakage characteristics of the following retrofilling materials; amalgam, zinc oxide eugenol cement, glass - ionomer cement, and cermet glass - ionomer cement. Root canals were prepared with step - back method and obturated with gutta percha and zinc oxide eugenol sealer. Root apex were resected 2 mm from apex and class I cavities were prepared with 2 mm or 4 mm depth. The cavities were filled with above materials. After application of varnish on all surface except resected surface, the roots were placed in 1 % methylene blue solution for 6 days. After longitudinal polishing to expose cental parts of filled materials, penetrated depths of dye were measured. The results were as follws. 1. As retrofilling material, glass ionomer cement filling groups showed less leakage than the other groups except zinc oxide eugenol cement filling group(p<0.01). 2. Amalgam filling groups had greater leakage than zinc oxide eugenol cement filling group(p<0.01). 3. 4 mm depth of retrofilled cavity had no effect on leakage characteristics compared with 2 mm depth cavity(p>0.05). 4. Glass ionomer cement and cermet glass ionomer cement filling groups showed less apical leakage than amalgam filling groups. But there was no statistical significance(p>0.05). 5. There was no difference in apical leakage between glass ionomer cement filling groups and cermet glass ionomer cement filling groups(p>0.05).

• The Korean Journal of Pain
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• v.12 no.2
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• pp.263-267
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• 1999

We have observed retroperitoneal hematoma after trigger point injections of quadratus lumborum in a patient with chronic low back pain. Severe flank pain and dyspnea was observed three hours after injection of local anesthetic and steroid to the trigger point of quadratus lumborum muscle. There was fuge hematoma in abdominal CT image around the right kidney, which displaced and compressed the kidney anteriorly. Following infusion of contrast media, extravasation through renal vein and IVC was notified. Patient had a past history of having been treated with platelet aggregation inhibitor and lower dose aspirin treatment after cerebral ischemia for a year, but coagulative function was within normal range. Patient was admitted 12 days for bed rest, pain control and transfusion. We need to take greater care with a frequent aspiration and exact direction of needle, during trigger point injection of quadratus lumborum, particu right side, to avoid vascular injury.

• Korean Journal of Human Ecology
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• v.12 no.1
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• pp.53-61
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• 2003

The purpose of this study was to compare the flat pattern with the draping pattern for the jacket. The results of this study were as follows: 1) According to the sensory evaluation for the movement, P2 flat pattern was more comfortable than the draping pattern at 88-94(N)-160 (77size). 2) The sensory evaluation was applied to evaluate the draping pattern was superior to the flat pattern for the collar at 82-90(N)-160(55size), 85-92(N)-160(66size) and 88-94(N)-160(77size). 3) The draping pattern was superior to the flat pattern in the sensory evaluation for the front and back. 4) Lee Hyung-Suck's flat pattern (P1) was better in appearance than the P2 and the draping pattern (P3) for the side sensory evaluation at 82-90(N)-160(55size) and 85-92(N)-160(66size).

• Proceedings of the Acoustical Society of Korea Conference
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• spring
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• pp.224-227
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• 1999

A high power deep-water sonar transducer of FFR (Free Flooded Ring) type has been designed using a coupled FE-BEM. The present sonar transducer is composed of rectangular piezoelectric ceramics and pie-shaped steels (or the advantage of simple fabrication. The dynamics of the sonar transducer is modelled in three dimensions and is analyzed with external electrical excitation conditions. Different results are available such as steady-state frequency response for TX and RX displacement modes, directivity patterns, back-scattering patterns, bandwidths, transmitting voltage responses and receiving sensitivity responses. The TV response shows a very high acoustic pressure of 150 dB/lV (ref $1{\mu}Pa$ at 1m) at 1900 Hz. This ultra high power response of the sonar transducer indicates a new possibility of the sonar transducer development.

• Proceedings of the Acoustical Society of Korea Conference
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• spring
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• pp.218-223
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• 1999

A piezoelectric flextentional deep-water sonar transducer has been simulated using a coupled FE-BEM. The dynamics of the sonar transducer is modelled in three dimensions and is analyzed with extern리 electrical excitation conditions as well as external acoustic pressure loading conditions. Different results are available such as steady-state frequency response for RX and TX, displacement modes, directivity patterns, back-scattering patterns, resonant frequencies, bandwidths, quality factors, transmitting voltage (TV) responses, input receiving sensitivity (RS) responses. White the present barrel-stave typed sonar transducer of the piezoelectric material is being simulated, the external surface of the transducer is modified in order to allow the same water pressure to be applied to the inner and the outer surfaces of the transducer. With this modification for deep-water application, the resonance frequency of the modified flextentional sonar transducer becomes much lower than that of the unmodified flextentional sonar transducer. The results of the present sonar transducer modelling are also compared with those of a commercial package such as ATILA.

• Journal of Welding and Joining
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• v.26 no.6
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• pp.67-73
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• 2008

Three-dimensional transient simulation of laser-GMA hybrid welding involving multiple physical phenomena is conducted neglecting the interaction effect of laser and arc heat sources. To reproduce the bubble and pore formations in welding process, a new bubble model is suggested and added to the established laser and arc welding models comprehending VOF, Gaussian laser and arc heat source, recoil pressure, arc pressure, electromagnetic force, surface tension, multiple reflection and Fresnel reflection models. Based on the models mentioned above, simulations of laser-GMA hybrid butt welding are carried out and besides the molten pool flow, top and back bead formations could be observed. In addition, the laser induced keyhole formation and bubble generation duo to keyhole collapse are investigated. The bubbles are ejected from the molten pool through its top and bottom regions. However, some of those are entrapped by solid-liquid interface and remained as pores. Those bubbles and pores are intensively generated when the absorption of laser power is largely reduced and consequently the full penetration changes to the partial penetration.