• 한국가스학회지
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• 제17권3호
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• pp.33-38
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• 2013

화학공장은 다량의 화학물질을 사용하기 때문에 사고가 발생하면, 많은 피해가 발생한다. 따라서 사고를 예방하기 위하여 위험성평가를 실시하고 있다. 화학공정은 HAZOP 기법을 이용하여 위험성평가를 실시하고 그 결과를 많이 활용하고 있다. 이 연구에서는 HAZOP 기법과 Bow-Tie 기법을 분석하고, Bow-Tie 위험성평가를 수행하였으며, 그 결과 다른 위험성평가에서 발견할 수 없었던 위험성이 도출되었고, 그 위험성을 제거하기 위한 14개의 개선사항이 도출되었다. Bow-Tie 위험성평가가 현장의 적용성과 위험요인을 도출하고 개선대책을 수립하는데 적합하다는 것을 확인하였다.

• 한국의류산업학회지
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• 제5권1호
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• pp.59-63
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• 2003

This study aims at developing of textile design expressed not only Korean natural image but also modern sensibility using fabrics dyed by tie dyeing with various natural dyes. And it attempts to practicality of high value-added goods revived traditional beauty. With the aqueous extract of various natural dyes, i.e., indigo, amur cock tree, onion's peel, citrus peel, mugwort, gromwell, sappan wood silk fabrics dyed by tie dyeing. Also various color changes were examined by mordants, i.e., aluminium sulfate, cupric acetate mono hydrate, ferrous chloride. With these fabrics, I made works using the techniques of applique, mola, fabric's connection and weaving. I think the developed textile design gave expression to natural image of Korean nation.

• Journal of electromagnetic engineering and science
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• 제4권1호
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• pp.13-16
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• 2004

In this paper, FDTD analysis of the bow-tie antenna is investigated by incorporating static field solution that is suitable to the bow-tie antenna without increasing computational time. Transforming static feld solution to the rotated grid system, we can obtain the transformed static field solution which is able to represent field behavior near the oblique edge line of the bow-tie antenna. The result shows a good agreement with a MoM analysis and is compared conformal modeling technique and regular FDTD method.

• 전기전자학회논문지
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• 제17권4호
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• pp.537-543
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• 2013

본 논문에서는 불연속 주파수 변조 기법을 사용하는 낮은 EMI 분산 스펙트럼 클록 발생기 (SSCG)를 제안한다. 제안된 SSCG는 높은 변조폭을 갖는 삼각 주파수 변조 기법을 사용한다. SSCG의 최대 시간 구간 오차 (MTIE)가 제한 기준을 넘어서면 SSCG의 출력 주파수가 분주기를 거쳐 시간 구간 오차 (TIE)의 값을 감소시킨다. 이러한 불연속 주파수 변조 기법은 주어진 MTIE 제한 기준 내에서 전자기 방사를 효과적으로 감소시킬 수 있다. 이 방법은 일반적인 SSCG보다 전자기 방사를 18.5dB 더 개선하였다.

• 전기학회논문지
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• 제66권9호
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• pp.1334-1340
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• 2017

In this paper, a tie-plate shape is optimized by using the numerical technique to reduce the stray load loss of the tie-plate which is a mechanical structure for assembling and supporting of the transformer core. The eddy current loss of the structure is calculated by an electromagnetic field FEM program and the results are compared with 4 different shapes of tie-plates. Since the thickness of the tie-plate is very thin, and the skin depth is very small, the number of FE elements for 3-D transformer model is too big to solve. So, the surface impedance boundary condition (SIBC) is used to reduce the system matrix size and its computing time. To verify the method a 2.5 MVA 22,900/380V distribution transformer is simulated using one objective function and three design variables with some constraints. The final optimized tie-plate has three slots of 6 mm width and 23 mm gap, and the loss is reduced by 75 %. Consequently, the proposed algorithm seems to be considerably applicable to electric machinery as well as power transformer.

• 대한가정학회지
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• 제32권5호
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• pp.201-216
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• 1994

The materialism prevalent in the modern industrial society and concern for the destruction of nature have led people to long for the returning to nature and excite their nostalgia for old. These phenomena induced in modern fashion naturalism retrospectivism ethnicism and primitivism. In the following we present our findings in regard the roles and relationships of the tie dying with the modern fashion design. in regard the roles and relationships of the tie dying with the modern fashion design. The common basic themes are founded as follows; 1. Naturalism: The tie dying is from very old times and has evolved in many parts of the world producing their own natural designs and color. They bear the characteristic of nature; the pleasantness smoothness and complexity. 2. Individualism and hand made: No two items produced by the tie dying technique are identical even though they are similar by design and their individuality is to some extent determined by chance. The retrospetivism and individualism are themes relating to the modern fashion. 3. Ethnicism and primitivism: The tie dying brings up the 'ethnic and traditional' to us and their designs and colors present the new images of the ethnic and primitive influences to the modern designs. 4. Ecology recyle and grunge look: The tie dying represent the recycle of the used natural resources such as making the old cloths useful again in new forms by tie dying them. The old clothes thus restored show wrinkled untidy and somewhat loosely fit form. This image of 'grunge look' is one of the central theme of the modern fashion.

• 전기전자학회논문지
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• 제22권3호
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• pp.793-799
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• 2018

An improved design of Ultra Wide Band(UWB) Bow-Tie antenna, which can control an enhanced wide stop-band, is presented. The mutually coupled slot-pair improves and controls the rejection band. The UWB antenna is composed of an electromagnetically coupled Bow-Tie patch and a parasitic ground patch, whose working frequency is extended to full UWB range in this work. By adding slot-pairs on the main patch and optimizing, they can give any requested wide rejection bands and sharp skirt characteristics, as is often required for UWB antennas and multi-band antennas. All the parameters are precisely calculated by an adequate optimization method. The Particle Swarm Optimization(PSO) technique is appropriately adopted. The proposed design and method is proved to give and control the sharp-skirt wide stop-band to UWB Bow-Tie antennas.

• Archives of Plastic Surgery
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• 제42권3호
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• pp.341-345
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• 2015

Background A tie-over dressing is the accepted method to secure skin grafts in order to prevent haematoma or seroma formation. We describe the novel application of a barbed suture tie-over for skin graft dressing. The barbs act as anchors in the skin so constant tensioning of the suture is not required. Methods From January 2014 to August 2014 we used the technique in 30 patients with skin defects requiring split-thickness or full-thickness grafts. Patient demographics, clinicopathological details and graft outcome were collected prospectively. Results The majority of cases were carried out for split-thickness skin grafts (n=19) used on the lower limb (n=20). The results of this novel technique were excellent with complete (100%) graft take in all patients. Conclusions Our results demonstrate the clinical application of a barbed device for securing skin grafts with excellent results. We find the technique quick to perform and the barbed device easy to handle, which can be applied without the need for an assistant.

• Journal of electromagnetic engineering and science
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• 제5권1호
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• pp.14-20
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• 2005

In this paper, a technique is presented for broadbanding the bow-tie slot antenna fed by a CPW(coplanar waveguide). The bandwidth performance of existing bow-tie slot designs is greatly enhanced by optimizing the slot shape and properly adjusting the characteristic impedance of the coplanar waveguide feeding the slot. To connect the 50-ohm input coaxial line to the CPW feed line, a linear taper in the CPW is employed. The designed antenna shows a 3.5 $\~$ 10.0 GHz impedance bandwidth, a 3.5 $\~$ 6.0 GHz pattern bandwidth, and a 5.5 $\~$ 7.5 dBi gain over 3.5 $\~$ 6.0 GHz. Above 6.0 GHz, the antenna radiation pattern appreciably deviates from the typical dipolar pattern.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.888-890
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• 2003

The objective of this investigation is to establish a simple yet effective block adjustment procedure for the orthorectification of multi-orbit satellite images. The major works of the proposed scheme are: (1) adjustment of satellite‘s orbit accurately, (2) calculation of the error vectors for each tie point using digital terrain model and ray tracing technique, (3) refining the orbit using the Least Squares Filtering technique and (4) generation of the orthophotos. In the process of least squares filtering, we use the residual vectors on ground control points and tie points to collocate the orbit. In orthorectification, we use the indirect method to generate the orthoimage. Test areas cover northern Taiwan. Test images are from SPOT 5 satellite. Experimental results indicate that proposed method improves the relative accuracy significantly.