• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.906-911
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• 2008

Because the perimeter of buildings is strongly influenced by solar and the outdoor air temperature, the area has different environmental properties compared to the interior of a building, as in summer heat gain, and in winter heat loss. In particular, if the external wall is glass, the characteristics of the glass material make it pervious to outside conditions, thereby making big changes to the thermal environment. By combining shading device and the efficient exhaust system, an energy saving can be achieved compared to no air barrier systems. The simplified air barrier system is developed with the idea that energy could be conserved by carefully and effectively blowing out the air caught between the glass surface and the roller blind. The way it is configured is therefore by making the roller blind's air-path, and by placing the air output ducts in the most optimum positions. This simplified air barrier system will give improvement in the thermal environment of the parameter area that is strongly affected by solar and the outdoor condition.

• Journal of Plant Biology
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• v.35 no.1
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• pp.53-60
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• 1992

This study has been carried out to investigate the ultrastructural changes in the associated with the disintegration of the storage materials in endosperm cell of ginseng (Panax ginseng C.A. Meyer) seed during after-ripening with light and electron microscope. The protein body of endosperm cells near the umbiliform layer showed various degenerative patterns, and so electron density of proteinaceous matrix was gradualJy decreased during afterripening. These results indicate that the decomposition of endosperm was already initiated during after-ripening. As the degeneration of endosperm was more progressed after the dehiscence of seed, non-decomposed part of protein body appeared amorphously with high electron density. Decomposed protein bodies were vacuolized with the loss of their matrix and gradually expanded by fusion. Also, spherosomes were gradually dissolved with the lowered electron density during the degeneration of endosperm. The vesicles of dictyosomes near the cell wall are observed in endosperm contacting with umbiliform layer and are fused with plasma membrane. Umbiliform layer which was the complex of the decomposed remnants of lysis and materials has strong stainability for toluidine blue and basic fuchsin.

• Fire Science and Engineering
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• v.21 no.4
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• pp.44-51
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• 2007

Most of the Korea temples of cultural property are wooden buildings and easy combusted. They are often located in mountain area far away from the city. It is very difficult to approach the fight area. The putting out is very difficult in the initial fire time. And for protecting the cultural property in the long-term continuous fire source there are some restrictions in water source and suppression system. In this paper the initial putting out fire due to the forest fire and the protection of cultural property in the long-term continuous fire source were researched. The improved project about fire control facilities of the Korea cultural property was proposed. In the proposed project the facilities using Water mist which can reduce more loss than existing facilities using water are applied. In view of the topographic position the method of eliminating the energy of combustibles and wall for cutting off the heat in the fire control facilities are also mentioned.

• The Journal of the Korea institute of electronic communication sciences
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• v.12 no.6
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• pp.989-996
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• 2017

The proposed directional pencil beam antenna consists of a waveguide feeder with bended elliptical conductor plate feed and a parabolic curved reflector. Two rectangular apertures located at the broad wall near the end of the feed waveguide inserted from behind the reflector are located at the focus of the reflector and emit electromagnetic energy with bended elliptical conductor plate. This plate is designed to reflect electromagnetic energy primarily and to face the main reflector. The two rectangular apertures located at the waveguide end have inwardly protruding tabs for impedance matching of the antenna system, the shape of the tabs is a truncated oval. The proposed parabolic reflector antenna has a diameter of 400 mm and a focal length of 134.23 mm. The antenna gain is 33.68 dBi at the center frequency of 16.5 GHz, the beam width is $3.3^{\circ}$ and the reflection loss is -15 dB. Using the HFSS-IE, simulation results are performed to validate the proposed antennas.

• Journal of Periodontal and Implant Science
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• v.40 no.2
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• pp.76-85
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• 2010

Purpose: This study aimed to evaluate the effectiveness of the modified sinus floor elevation technique described hereafter as a "hybrid technique," in 11 patients with severely resorbed posterior maxillae. Methods: Eleven patients who received 22 implants in the maxillary premolar and molar areas by the hybrid technique were enrolled in this study. A slot-shaped osteotomy for access was prepared on the lateral wall along the lower border of the sinus floor. The Schneiderian membrane was fully reflected through the lateral slot. Following drilling with the membrane protected by a periosteal elevator, the bone was grafted. All implants were placed simultaneously with sinus augmentation. The cumulative success rate was calculated and clinical parameters were recorded. Radiographic measurements were performed. Results: All implants were well maintained at last follow up (cumulative success rate=100%). The mean residual bone height, augmented bone height, crown-to-implant ratio, and marginal bone loss were $4.1{\pm}1.64mm$, $8.76{\pm}1.77mm$, $1.21{\pm}0.34mm$, and $0.34{\pm}0.72mm$, respectively. Conclusions: Simultaneous implant placement with sinus augmentation by hybrid technique showed successful clinical results over a 2-year observation period and may be a reliable modality for reconstruction of a severely resorbed posterior maxilla.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.14 no.1_2
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• pp.105-116
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• 1992

Latissimus dorsi myocutaneous flap is useful for the breast reconstruction, chest wall coverage, free flap transfer, and head and neck area reconstruction, especially in large defect. We have had some experience of 5-pedicled and 1-free latissimus dorsi myocutaneous flap in head and neck area and found many advantages and some problems. The conclusions were as follows : 1. Potentially large flap size enabled us agressive tumor resection and reconstruction. 2. Speedy and easy flap elevation and long vascular pedicles reduced operation time and flap failure. 3. Due to fewer complication and functional loss of doner site, pedicled latissimus dorsi flap was a good choice for large head and neck reconstruction. 4. Because of flap bulkness, thin and small defect was not appropriate for reconstruction.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.3
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• pp.551-560
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• 2011

Recently, There has been increasing concern about WLAN-based indoor positioning system. Most of the existing WLAN-based positioning systems use a fingerprinting method as a main approach. In the fingerprinting approach, the accuracy of the location of a mobile objects is proportional to the number of reference points. However, depending on the increasing number of reference points in the training phase, it requires more time and effort to create fingerprint database. To solve these problems, we propose the new indoor positioning algorithm that calculate the distance between a mobile objects and an AP using the information of surrounding environment WLAN based APs and applied the particle filter to the proposed algorithm in order to improve the accuracy of the estimated location in this paper. To implement this algorithm, at first environmental information database such as wall, iron door, glass door, partition etc. existing in the periphery of the AP should be established. The positioning use attenuation model and path loss model. Our experimental results with proposed algorithm are verified that the positioning accuracy was low but solved the problems with fingerprinting, compared with other positioning algorithms.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.5
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• pp.389-395
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• 2005

The etching technology of the high aspect ratio contact(HARC) is necessary at the critical contact processes of semiconductor devices. Etching the $SiO_{2}$ contact hole with the sub-micron design rule in manufacturing VLSI devices, the unexpected phenomenon of 'profile tilting' or 'bottom distortion' is often observed. This makes a short circuit between neighboring contact holes, which causes to drop seriously the device yield. As the aspect ratio of contact holes increases, the high C/F ratio gases, $C_{4}F_{6}$, $C_{4}F_{8}$ and $C_{5}F_{8}$, become widely used in order to minimize the mask layer loss during the etching process. These gases provide abundant fluorocarbon polymer as well as high selectivity to the mask layer, and the polymer with high sticking yield accumulates at the top-wall of the contact hole. During the etch process, many electrons are accumulated around the asymmetric hole mouth to distort the electric field, and this distorts the ion trajectory arriving at the hole bottom. These ions with the distorted trajectory induce the deformation of the hole bottom, which is called 'profile tilting' or 'bottom distortion'. To prevent this phenomenon, three methods are suggested here. 1) Using lower C/F ratio gases, $CF_{4}$ or $C_{3}F_{8}$, the amount of the Polymer at the hole mouth is reduced to minimize the asymmetry of the hole top. 2) The number of the neighboring holes with equal distance is maximized to get the more symmetry of the oxygen distribution around the hole. 3) The dual frequency plasma source is used to release the excessive charge build-up at the hole mouth. From the suggested methods, we have obtained the nearly circular hole bottom, which Implies that the ion trajectory Incident on the hole bottom is symmetry.

• Proceedings of KOSOMES biannual meeting
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• 2007.05a
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• pp.109-113
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• 2007

Yacht have an high powered main engine relatively light hull, so the noise generated from the engine have a bad influence upon the crew and passenger. Recently, cruise yacht is made an attempt by domestic production skill, however the insulation skill of the noise made by the main engine is not satisfy the real purchasing power of the buyer. Like this, yacht cabin's noise level is becoming the barometer to decide the purchase. the method to insufficient. However, if we use the skill of the monitoring equipment and the genetic algorithm system, the circumference of the main engine can be enclosed by an high quality absorbtion wall and the noise levels of the cabins are improved. In this study, the sound absorbtion barrier is experimentally researched by change the volume and the length of the neck for the Helmholtz resonator as the resonator can absorb the noise effectively.

• Journal of the Society of Naval Architects of Korea
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• v.28 no.2
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• pp.293-306
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• 1991

During the last few years recommendations or regulations concerning permissible noise levels on shirts have been issued by the authorities in most countries. For these reasons the need for useful and accurate noise prediction computer programs has been emphasized. A noise prediction program can make it possible to find the most economical solution to achieve a certain noise requirement. This paper attempts to develop a noise prediction computer program using statistical energy analysis(SEA). In this paper, the SEA is used to predict the sound transmission loss for airborne noise and the vibration amplitude of the panel consisting of ship spaces such as floor, wall, and ceiling for structureborne noise. And in order to verify the prediction, a small passenger vessel, G/T120 tons, is selected. It has been shown that the prediction is capable of giving results in good practical agreement with measurements and therefore it is useful for predicting the nolle levels in ships and establishing the countermeasures at early design stage.