• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 I
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• pp.7-10
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• 2003

본 논문에서는 중국의 광산에서 수행되고 있는 통신인 지하이동통신을 요약하여 설명하고, 이에 대한 문제점을 논의한다. 또한, 지하에서 스프레드 스펙트럼(spread spectrum) 통신이 장애에 강하고, CDMA가 사용하기에 용이하고 적합하다는 것을 제안한다. 그리고 중국 광산에서 사용되는 스프레드 스펙트럼 통신의 앞으로 전망을 설명하고 실행가능하고 실용적 인 프로그램을 제안한다.

• 한국의류산업학회지
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• 제9권4호
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• pp.391-400
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• 2007

This purpose of this study is to announce the research for the formative characteristics and the constructive characteristics for the 23 pair of pants excavated from the tomb of Yeosan Song's family at Mokdal Dong in Daejeon. Men and women wore the open-type over the close-type pants. Song Hyo-sang and Chungjoo Park wore the 1 or 2 pairs of the open-type pants over the 3 pairs of close-type pants. Song Hee-jong and his wife Sonhung An wore a pair of the open-style pants over the 1 or 2 pairs of pants. It was due to the shortage of goods by the war that Song Heejong had less shrouds than Song Hyosang. The pants were almost made of the cotton and the silk. The open-type pants worn inside was made of the cotton but outside was made of the silk. That time the cotton was used for the unlined underwears for the health and the protection against the cold and the hot. The silk was used for the outwear. In the construction type, 12 pairs of pants were unlined, 6 pairs of pants were quilted, 4 pairs of pants were padded, and 1 pair of pants was lined. All unlined were the close-type and the quilted and padded pants were the open-type, which were worn inside. Lined type was just one. In the wearing order of shrouds, type, textile, and constructive type, Song Hyosang and Chungjo Park were similar, Song Heejong and Sonhung An were similar.

• 한국언어정보학회:학술대회논문집
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• 한국언어정보학회 2002년도 Language, Information, and Computation Proceedings of The 16th Pacific Asia Conference
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• pp.69-78
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• 2002

This paper discusses issues in building a 54-thousand-word Korean Treebank using a phrase structure annotation, along with developing annotation guidelines based on the morpho-syntactic phenomena represented in the corpus. Various methods that were employed for quality control and the evaluation on the Treebank are also presented.

• Applied Microscopy
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• 제43권2호
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• pp.81-87
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• 2013

The influence of carbide formation on mechanical properties has been investigated in carburized steels. Through controlled diffusion and precipitation processes, the morphologies of carbides could be changed and then fine, networked, and spherical shapes at carburized layers were obtained. These morphological changes affected tensile and bending fatigue properties of the steel. The fine and the spherical carbides acted as resistance sites against crack propagation, which improved the mechanical properties. However, the networked carbides deteriorated the properties because the cracks propagated along the boundaries of them. These results indicate that the morphological control of carbides is one of important keys to improve the mechanical properties.

• Journal of Veterinary Science
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• 제24권2호
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• pp.30.1-30.6
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• 2023

A 4-year-old Chihuahua dog was referred for bilateral corneal ulcers. Slightly raised white fluorescein-positive plaque-like corneal lesions in both eyes appeared as intense hyperreflective areas with posterior shadowing on optical coherence tomography (OCT). Based on corneal cytology and culture, Candida albicans-induced fungal keratitis was diagnosed. Despite treatment, on OCT, endothelial plaques, increased stromal infiltration thickness, vertical shapes of the ulcer edge, and necrotic stromal space were judged to be aggravation of the disease, and surgery was performed. Conjunctival grafting surgery with topical 1% voriconazole effectively resolved fungal keratitis. OCT can provide detailed and objective information related to the disease prognosis.

• 대한전자공학회논문지TC
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• 제41권11호
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• pp.33-38
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• 2004

본 논문에서는 시간분산 통신로에 주파수선택성 페이딩과 다중경로 페이딩을 극복하기 위해서, 격자부호 변조와 OFDM을 결합한, 격자부호 직교주파수분할 다중통신방식(TC-OFDM) 시스템의 성능을 분석한다. 시간분산 통신로를 대상으로 부호율 2/3인 격자부호 8DPSK- OFDM의 BER 성능을 모의실험하고 분석한다. OFDM의 여러 반송파 수에 대한 격자부호의 설계를 논의한다. 실험결과, BER 10/sup -3/에서 TC-OFDM 시스템은 부호화를 하지 않은 OFDM 시스템에 비해서 6 dB 부호이득을 얻을 수 있음을 알았다.

• 대한전자공학회논문지TC
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• 제41권11호
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• pp.25-32
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• 2004

본 논문에서는 전력선통신에서 발생하는 잡음에 대해서 DSSS을 적용할 수 있는 가능성을 분석했다. 이 잡음은 4가지가 있는데, 이들 잡음을 분석하기 위해서 특성에 따라서 실제로 전력선에서 발생하는 잡음원을 만들었다. 이들 잡음모델을 대상으로 DSSS을 적용한 BPSK의 BER 성능을 DSSS을 적용하지 않는 BPSK의 경우와 비교해서 모의실험하고 분석했다. 그 결과, DSSS을 적용한 BPSK의 경우가 DSSS을 적용하지 않는 BPSK의 경우에 비해서 8 dB 개선되었음을 알 수 있었다.

• 한국도로학회논문집
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• 제19권3호
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• pp.65-70
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• 2017

PURPOSES : Pavement Management System contains the data that describe the condition of the road. Under limited budget, the data can be utilized for efficient plans. The objective of this research is to develop a mixed integer program model that maximizes remaining durable years (or Lane-Kilometer-Years) in road maintenance planning. METHODS : An optimization model based on a mixed integer program is developed. The model selects a cluster of sectors that are adjacent to each other according to the road condition. The model also considers constraints required by the Seoul Metropolitan Facilities Management Corporation. They select two lanes at most not to block the traffic and limit the number of sectors for one-time construction to finish the work in given time. We incorporate variable cost constraints. As the model selects more sectors, the unit cost of the construction becomes smaller. The optimal choice of the number of sectors is implemented using piecewise linear constraints. RESULTS : Data (SPI) collected from Pavement Management System managed by Seoul Metropolitan City are fed into the model. Based on the data and the model, the optimal maintenance plans are established. Some of the optimal plans cannot be generated directly in existing heuristic approach or by human intuition. CONCLUSIONS:The mathematical model using actual data generates the optimal maintenance plans.

• 한국압력기기공학회 논문집
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• 제4권2호
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• pp.50-56
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• 2008

The tubes in heat exchanger are typically made of copper alloy, stainless steel, carbon steel, titanium alloy material. Type-439 ferritic stainless steel is ferromagnetic material, and furnish higher heat transfer rates than austenitic stainless steels and higher resistance to corrosion-induced flaws. Ferritic stainless steel can be found in low-pressure(LP) feedwater heaters and moisture separator reheaters(MSRs) in turbine system. LP feedwater heaters generally utilize thin wall Type-439 stainless steel tubing, whereas MSRs typically employ a heavier wall tubing with integral fins. Service-induced damage can occur on the O.D(outside diameter) surface of Type-439 ferritic stainless steel tubing which is employed for MSRs tubing, and the most typical damage mechanism is vibration-induced tube-to-TSP(tube support plate) wear and fatigue cracking. The wear has been reported that occurs mainly on the OD surface. Accordingly, in this study, we have evaluated the flaw sizing capability of magnetic saturation eddy current technique using magnetic saturation probe and flawed specimen.

• 한국문헌정보학회지
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• 제51권2호
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• pp.237-253
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• 2017

상호대차 서비스 운영의 효율화를 위해서 시스템적 접근과 같은 다양한 방법이 모색되고 있다. 본 연구는 그 가운데 상호대차 대출 요청의 이용자 대기시간을 줄일 수 있는 운영관리 방법에 대해서 제시하였다. 지역 내 상호대차 대출의 이용자 대기 시간은 2~3일로 안내되고 있는데 이와 같은 대기가 발생하는 가장 큰 이유는 도서 배송 차량의 이동경로 및 도서 배송량 결정에 비효율성이 있기 때문이다. 이를 해결하기 위해 혼합정수계획모형이라는 수리적 모형을 통해 도서 배송량을 최대화할 수 있는 차량 경로이동 방법을 제시하였다. 그리고 실제 도서관의 상호대차 요구량 자료를 이용하여 하루 가용한 시간 별, 최적의 도서 이동 및 차량 경로 해법을 제안하였다.