• 전자공학회논문지CI
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• 제45권6호
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• pp.77-86
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• 2008

기존의 클러스터 라우팅 방식은 클러스터 헤드를 선출하여 클러스터 내의 멤버 노드들로부터 정보를 수집하고 압축하여 기지국에 전송함으로써 에너지 효율을 높일 수 있는 대표적인 방식이다. 그러나 클러스터 형성 단계 중 매 라운드마다 셋업 단계에서 선출된 클러스터 헤드와 클러스터 내의 멤버 노드들 간의 빈번한 정보 교환으로 인해 발생하는 불필요한 에너지 소모는 클러스터 라우팅 방식이 해결해야 하는 과제이다. 본 논문에서는 셋업 단계에서의 선출된 클러스터 헤드와 기존의 클러스터 헤드 사이에 변경되지 않는 중첩된 영역에 속한 멤버 노드들을 계산함으로써, 중첩된 멤버 노드들의 셋업 단계에서의 불필요한 송수신 횟수를 줄여 정보 교환을 최소화하였다. 또한 최적의 클러스터 구성을 위해 상위 클러스터 헤드의 방향성을 고려하였다. 따라서 셋업 단계에서의 소모되는 에너지를 절약하여 안정 단계에서 효율적으로 사용함으로써, 에너지의 효율적인 사용과 전체적인 네트워크의 생존시간을 증가시키고자 하며, 전체 네트워크내의 멤버들에게 클러스터 헤드가 될 수 있는 균등한 기회를 주고자 하는 클러스터 헤드 선출 기법을 제안한다.

• 천문학논총
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• 제30권2호
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• pp.559-563
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• 2015

Monitor of All-sky X-ray Image (MAXI) is a Japanese X-ray all-sky surveyer mounted on the International Space Station (ISS). It has been scanning the whole sky since 2009 during every 92-minute ISS rotation. X-ray transients are quickly found by the real-time nova-search program. As a result, MAXI has issued 133 Astronomer's Telegrams and 44 Gamma-ray burst Coordinated Networks so far. MAXI has discovered six new black holes (BH) in 4.5 years. Long-term behaviors of the MAXI BHs can be classified into two types by their outbursts; a fast-rise exponential-decay type and a fast-rise flat-top one. The slit camera is suitable for accumulating data over a long time. MAXI issued a 37-month catalog containing 500 sources above a ~0.6 mCrab detection limit at 4-10 keV in the region ${\mid}{b}{\mid}$ > $10^{\circ}$. The SSC instrument utilizing an X-ray CCD has detected diffuse soft X-rays extending over a large solid angle, such as the Cygnus super bubble. MAXI/SSC has also detcted a Ne emission line from the rapid soft X-ray nova MAXI J0158-744. The overall shapes of outbursts in Be X-ray binaries (BeXRB) are precisely observed with MAXI/GSC. BeXRB have two kinds of outbursts, a normal outburst and a giant one. The peak dates of the subsequent giant outbursts of A0535+26 repeated with a different period than the orbital one. The Be stellar disk is considered to either have a precession motion or a distorted shape. The long-term behaviors of low-mass X-ray binaries (LMXB) containing weakly magnetized neutron stars are investigated. Transient LMXBs (Aql X-1 and 4U 1608-52) repeated outbursts every 200-1000 days, which is understood by the limit-cycle of hydrogen ionization states in the outer accretion disk. A third state (very dim state) in Aql X-1 and 4U 1608-52 was interpreted as the propeller effect in the unified picture of LMXB. Cir X-1 is a peculiar source in the sense that its long-term behavior is not like typical LMXBs. The luminosity sometimes decreases suddenly at periastron. It might be explained by the stripping of the outer accretion disk by a clumpy stellar wind. MAXI observed 64 large flares from 22 active stars (RS CVns, dMe stars, Argol types, young stellar objects) over 4 years. The total energies are $10^{34}-10^{36}$ erg $s^{-1}$. Since MAXI can measure the spectrum (temperature and emission measure), we can estimate the size of the plasma and the magnetic fields. The size sometimes exceeds the size of the star. The magnetic field is in the range of 10-100 gauss, which is a typical value for solar flares.

• 대한원격탐사학회지
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• 제38권2호
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• pp.167-177
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• 2022

위성 영상 촬영 후 지상국에 전송된 영상을 이용하여 최종 위성 영상을 획득하기 위해 많은 영상 전/후 처리 과정이 수반된다. 전/후처리 과정 중 레벨 1R 영상에서 레벨 1G 영상으로 변환 시 기하 보정은 필수적으로 요구된다. 기하 보정 알고리즘에서는 보간 기법을 필연적으로 사용하게 되며, 보간 기법의 정확도에 따라서 레벨 1G 영상의 품질이 결정된다. 또한, 레벨 프로세서에서 수행되는 보간 알고리즘의 고속화 역시 매우 중요하다. 본 논문에서는 레벨 1R에서 레벨 1G로 변환 시 기하 보정에 필요한 경량화된 심층 컨볼루션 신경망 기반 보간 기법에 대해 제안하였다. 제안한 기법은 위성 영상의 해상도를 2배 향상하며, 빠른 처리 속도를 위해 경량화된 심층 컨볼루션 신경망으로 딥러닝 네트워크를 구성하였다. 또한, panchromatic (PAN) 밴드 정보를 활용하여 multispectral (MS) 밴드의 영상 품질 개선이 가능한 피처 맵 융합 방법을 제안하였다. 제안된 보간 기술을 통해 획득한 영상은 기존의 딥러닝 기반 보간 기법에 비해 정량적인 peak signal-to-noise ratio (PSNR) 지표에서 PAN 영상은 약 0.4 dB, MS 영상은 약 4.9 dB 개선된 결과를 보여주었으며, PAN 영상 크기 기준 36,500×36,500 입력 영상의 해상도를 2배 향상된 영상 획득 시 기존 딥러닝 기반 보간 기법 대비 처리 속도가 약 1.6배 향상됨을 확인하였다.

• 한국토양비료학회지
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• 제11권1호
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• pp.9-16
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• 1978

사과나무용 복합비료(複合肥料)의 합리적(合理的) 조성비(組成比)를 찾고자 사소첨가(硼素添加) 복비(複肥) 시제품(試製品)($N-P_2O_5-K_2O-B_2O_5-MgO$: 10-10-0.2-1.0)을 요소(尿素), 중과석(重過石), 염화가리(鹽和加里) 일반복비(一般複肥)(22-22-11)와 붕사(硼砂)를 사용(使用) 왜성(矮性)후지 일년생묘목(一年生苗木)과 수퍼타입스서크림슨 삼년생(三年生)을 비교적(比較的) 척박(瘠薄)한 삼개토양(三個土壤)에 주당총엽중(株當總葉重), 또는 주당신초장등(株當新稍長等) 생육량조사(生育量調査)로 실시(實施)하여 다음과 같은 결과(結果)를 얻었다. 1. 후지에서는 붕소첨가(硼素添加) 복비(複肥)>일반복비(一船複肥)>삼요소단비(三要素單肥)>삼요소단비(三要素單肥)+붕소(硼素)>붕소첨가복비(硼素添加複肥)+붕소증시(硼素增施)(17배(培))>무인산(無燐酸)의 순(順)으로 효과가 적어졌다. 2. 스타크림슨 삼년생(三年生)은 붕소복비(硼素複肥)+붕소(硼素) 및 인산증시(燐酸增施)>붕소복비(硼素複肥)>일반복비(一般複肥)>단비(單肥)>붕소복비(硼素複肥)+(붕소증시)硼素增施>단비(單肥)+붕소(硼素)>무인산(無燐酸)의 순(順)이었으며 척박(瘠薄)한 토양(土壤)에 퇴비(堆肥)를 사용(使用)치 않으면 붕소증시(硼素增施)에서 극히 불량(不良)하고 단비붕소(單肥硼素)가 가장 좋고 붕소첨가(硼素添加) 복비(複肥)가 다음이었다. 3. 붕소(硼素)만 증시(增施)되면 생육(生育)이 불량(不良)하였으나 인산(燐酸)과 동시(同時)에 증시(增施)되는 경우 효과가 나타나고 토양중(土壤中)에 붕소(硼素)가 삼요소(三要素)와 동일(同一)한 위치(位置)에 분포(分布)할 때 효과가 좋은 것으로 추정(推定)되었다. 4. 사과나무에 대(對)한 시비반응(施肥反應)은 엽폭(葉幅)에는 없으며 엽장(葉長)에서 인정(認定)되고 엽당중량(葉當重量)에서 잘 반영되는 것으로 보아 시비효과지표로 표고신장량(標高伸長量), 간주장(幹周長) 간비대량(幹肥大量)보다도 주당신초장(株當新稍長) 및 주당총엽중(株當總葉重)이 좋을것으로 보였다. 5. 사과용 붕소첨가(硼素添加) 복비(複肥)의 조성(組成)은 10-10-10-0.2보다 10-20-10-0.6($N-P_2O_5-K_2O-B_2O_5$)이 척박지(瘠薄地) 및 중간비옥도지용(中間肥沃度地用)으로 좋을 것으로 보였다. 6. 엽분석결과(葉分析結果) 붕소첨복비중(硼素添加複肥中) Mg가 Fe와 함께 엽중증가(葉重增加)에 기여(寄與)한 것으로 보여 Mg 효과가 인정(認定)되었다.

• 산경연구논집
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• 제1권1호
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• pp.5-12
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• 2010

The retail business of drugstore was introduced to Korea for the first time 10 years ago. Since Olive Young introduced a retail store in the name of drugstore in 1999 for the first time in Korea, new distribution channel combining drugstore, cosmetic products and dairy products, etc has been made. At initial stage, the new distribution channel grew up slowly because of low specialty and economic stagnation. However, the three big distribution channels, that is to say, Olive Young (CJ), Watsons (GS) and W Store (Kolon Well Care), etc, were established to produce new distribution system following large-scaled discount stores as well as convenience stores. The purpose of the study is to investigate ways making Korean style drugstore be new retail business in addition to traditional markets, department stores, E-Mart and other general super markets and to examine problems preventing the drugstore from being promoted and to find out solutions. The speciality retailers that is called a category killer attacking department stores as well as marts is expanding market quickly. New consumption trend that gives priority to wellbeing is being expanded in accordance with high level of standards of living life: The drugstore is thought to be new alternative of distribution because it keeps special products. Young ladies who are main customers of drugstores respond to the trend sensitively to have more buying power that is thought to be promising. And, consumers' desire has become concrete and special. This is because consumers want not only convenient shopping but also special shopping system that is current trend. These days, so called Multi-shop and Total shop and other special shops have been recently opened. Special multi-shop has been concentrated on fashion product and miscellaneous goods so far: Health total wellbeing shop shall be popular in accordance with wellbeing trends. Drugstores can play an important role. Drugstores were opened for the first time ten years ago. In particular, Olive Young succeeded in going into the black after making efforts for a long time by many persons. Drugstores could succeed in the business owing to many persons in the past as well as customers who liked drugstores. However, drugstores once lost ways and recorded poor business results. The three drugstores, that is to say, Olive Young, Watsons making efforts to go into the black and W-Store pursuing traditional drugstore shall compete each other and make effort to satisfy customers' desire. In that way, the three drugstores can be assured of present business as well as future business. The consumers' demand trend has become special at sub-division so that drugstores that can satisfy the demand can succeed in the business. Large businesses may be more interested in the 4th generation retail business to produce good income and to have bright future. Drugstore business and market are likely to expand and develop owing to large business' participation in drugstore business. Drugstores expanded shop at Seoul and Gyeonggi-do until middle of 2000. Drugstore business at station sphere in Seoul and Gyeonggi-do that have high ratio of temporary population has low customer loyalty to have limitation on continuous growth. Since 2009, drugstores have opened new shops at local towns: From the year of 2010, drugstores need to establish multiple shop strategy by accelerating business speed and to allow customers to drop in the shop anywhere in the nation and to enter consumers' life deeply, so that they can strengthen business base definitely. Drugstores need to have price competitiveness to have multiple shop opening strategy and to satisfy consumers and to supply high quality services that is future subject to solve. And, Olive Young and Watsons that are Korean style drugstore need to keep system in order and to strengthen substance as Korean style drugstore and to expand marketing, so that they can get business outcome within 5 years that was done 10 years before and they become the 4th generation retail business. The study had difficulties at collecting material from the three drugstore because of poor cooperation. And, the author had great difficulty at collecting statistical material that was made in disorder. Further effort is needed considering such problems.