• 한국수자원학회논문집
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• 제54권8호
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• pp.617-628
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• 2021

가뭄은 심각한 사회적 경제적 손실을 초래하는 주요 자연재해이다. 지역 가뭄 예측은 가뭄 대비에 중요한 정보를 제공할 수 있다. 본 연구에서는 한반도 동남부 부산-울산-경남 지역에서 1981년부터 2020년까지 10개 관측소의 과거 가뭄지수 및 기상 관측자료를 사용하여 가뭄을 예측하는 새로운 기계학습모델을 제안한다. 베이지안 최적화기법을 이용하여 하이퍼 파라미터가 튜닝된 Random Forest, XGBoost, Light GBM 모델을 구축하여 1개월 뒤의 6개월 시간 척도의 증발 수요 가뭄지수를 예측하였다. 단일 지점별 모델과 지역 모델을 각각 구성하여 모델 성능을 비교하였다. 또한 지역 모델을 기반으로 개별 지점의 자료에 대해 미세조정된 모델을 구성하여 모델 성능을 높일 가능성을 살펴보았다.

• 한국안전학회지
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• 제28권2호
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• pp.78-83
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• 2013

The traffic culture index is used as a major index in evaluating the traffic safety services of local governments and also serve as important data for the planning and implementation of traffic safety services. However, as the traffic culture index gradually became a standard for comparison among local governments, in part, certain cases arose which questioned the grounds for selecting variables for the index and the validity of the index in terms of its influential relationship between evaluation items. This study analyzed the index's influential relationship by utilizing a PLS structural equation model based on the evaluation results of the 2011 traffic culture index. A variable-linking model was created which recognized the relativity taking into account of the indirect effects between latent variables and this model was proven to be a model suitable in explaining the traffic culture index with a 97.8% explanation power. It was found that traffic safety(0.530), driving behavior(0.527), pedestrian behavior(0.187) and vulnerable road users(0.147), in such order, had an effect on the traffic culture index. It was also found that human casualties due to traffic accidents under "traffic safety" and traffic light compliance rate under "driving behavior" had an important effect. The study showed that motor vehicle share in illegal parking in school zones did not have a valid explanation power regarding "vulnerable road users".

• Journal of Contemporary Eastern Asia
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• 제19권1호
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• pp.59-83
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• 2020

This paper examines the actions and the factors driving those actions to reduce energy consumption and enhance energy efficiency taken by United States cities. While not much empirical evidence is available on why governments pursue practical sustainability actions, we attempt to shed more light on this important topic by empirically identifying factors that contribute to concrete actions toward sustainability policies. We adopt political market theory as a basic theoretical framework with policy-making applied to city energy consumption. Using the 2010 ICMA (local government sustainability policies and program) data, this study expands the focus of analyses to evaluate the effect of the form of government on energy consumption and energy efficiency by using multiple regression analysis. The findings show that at the city level, the mayor-council form of government are negatively associated with governments' efforts to reduce energy consumption. However, cities with at-large elections and municipal ownership are more likely to adopt sustainability actions. We also find that a large-scale economy has significant effects on the effort to reduce city energy consumption and improve energy efficiency. This shows that environmental policies are directly connected to locally relevant affairs, including housing, energy use, green transportation, and water. Thus, local level administrators could take an executive role to protect the environment, encourage the development of alternative energy, and reduce the use of fossil fuel and coal energy. These efforts can lead to important environmental ramifications and relevant actions by municipal governments.

• 천문학회지
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• 제37권5호
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• pp.427-431
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• 2004

We use simulations of large-scale structure formation to study the build-up of magnetic fields (MFs) in the intergalactic medium. Our basic assumption is that cosmological MFs grow in a magnetohy-drodynamical (MHD) amplification process driven by structure formation out of a magnetic seed field present at high redshift. This approach is motivated by previous simulations of the MFs in galaxy clusters which, under the same hypothesis that we adopt here, succeeded in reproducing Faraday rotation measurements (RMs) in clusters of galaxies. Our ACDM initial conditions for the dark matter density fluctuations have been statistically constrained by the observed large-scale density field within a sphere of 110 Mpc around the Milky Way, based on the IRAS 1.2-Jy all-sky redshift survey. As a result, the positions and masses of prominent galaxy clusters in our simulation coincide closely with their real counterparts in the Local Universe. We find excellent agreement between RMs of our simulated galaxy clusters and observational data. The improved numerical resolution of our simulations compared to previous work also allows us to study the MF in large-scale filaments, sheets and voids. By tracing the propagation of ultra high energy (UHE) protons in the simulated MF we construct full-sky maps of expected deflection angles of protons with arrival energies $E = 10^{20}\;eV$ and $4 {\times} 10^{19}\;eV$, respectively. Accounting only for the structures within 110 Mpc, we find that strong deflections are only produced if UHE protons cross galaxy clusters. The total area on the sky covered by these structures is however very small. Over still larger distances, multiple crossings of sheets and filaments may give rise to noticeable deflections over a significant fraction of the sky; the exact amount and angular distribution depends on the model adopted for the magnetic seed field. Based on our results we argue that over a large fraction of the sky the deflections are likely to remain smaller than the present experimental angular sensitivity. Therefore, we conclude that forthcoming air shower experiments should be able to locate sources of UHE protons and shed more light on the nature of cosmological MFs.

• 한국약용작물학회지
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• 제7권3호
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• pp.213-217
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• 1999

뿌리에 의한 영양번식으로 증식하는 지황은 바이러스에 심하게 삼염되어있어 종자를 이용한 우량종근을 생산할 목적으로 종자특성과 발아에 미치는 요인과 알진산으로 인공피막한 처리를 검토한 결과는 다음과 같다. 지황종자의 특성으로 협당종자수는 서천재래 61개에 비하여 지황1호가 207개로 많았고 1,000립중도 서천재래 70mg에 비하여 지황1호가 130mg으로 무거웠다. 지황종자는 당년채종('98)한 종자보다 전년도 채종 후 상온 저장한 종자에서 높은 발아율을 보여 미세립 종자지만 휴면현상이 있었고 온도 차이에 따른 발아는 차이를 보여 $15^{\circ}C$에서는 9일까지 발아하지 않았으나, $30^{\circ}C$에서는 2일후 28.5%, 6일후 41.6%로 높았다. 종자파종의 생력화를 목적으로 지황종자를 알진산 피막처리 하였을 때 파종후 20일에 발아율이 83.2% 정도였다. 알진산 처리농도는 2%의 저농도에서 발아율이 높았고 인공피막내 함유 종자수는 3개이상까지 많을수록 양호하였으며 저온처리는 초기발아가 지연되었다.

• 한국도서관정보학회지
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• 제48권3호
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• pp.207-232
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• 2017

최근 지역대표도서관을 중심으로 해당 지역 도서관자료를 체계적으로 이관받아 장기적으로 보존하기 위한 노력이 지역별로 진행되고 있다. 이 연구는 지역대표도서관 공동보존서고 운영계획 수립단계에서 첫걸음은 지역 내 단위도서관의 자료보존현황을 파악하고 현장 사서의 의견을 수렴하여 공동보존서고 계획과정에 반영하는 일이라는 관점에서 출발하였다. 이에 이 연구는 부산지역 공공도서관의 자료보존현황을 바탕으로 부산도서관 공동보존서고 운영방안을 논의하고자 하였다. 구체적으로는 1) 부산지역 공공도서관의 자료보존 현황과 부산도서관 공동보존서고 운영에 대한 사서들의 의견을 조사하고, 2) 부산도서관 공동보존서고 운영방안을 자료이관방안과 공간운영방안 등으로 나누어 제안하는 것을 목적으로 한다.

• 정보처리학회논문지C
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• 제11C권2호
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• pp.219-228
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• 2004

무선LAN(wireless Local Area Network)이란 옥내 또는 옥외 환경에서 무선으로 네트워크 환경을 구축하는 것을 말하며, 기술적인 측면에서는 허브(Hub)에서 PC(Personal Computer), 노트북PC, PDA 등 클라이언트까지 유선 대신 전파나 빛을 이용하여 네트워크를 구축하는 방식을 말한다. 현재, IEEE 802.11 WG(Working Group) 중에는 AP(Access Point)간의 표준화된 프로토콜을 개발하는 TGf(Task Group F)가 있다. 이 그룹에서는 서로 다른 제조업체에서 생산한 AP 간의 상호연동을 보장하기 위한 IAPP(Inter Access Point Protocol)를 제안하였는데, 이는 동일 서브네트워크 내의 서로 다른 AP간에 이동성을 보장하기 위한 프로토콜로, STA(Station)들이 이동할 때 재인증 과정을 거치지 않고 AP간의 Security Context 정보나 Layer 2 forwarding 정보를 공유함으로서 STA간의 seamless 연결성을 제공한다. 본 논문에서는 위의 AP간 메시지 전달 시 발생할 수 있는 보안성이 요구되는 iapp-move 요청, 응답 메시지를 이미 사용되고 있는 인증된 경로를 통해 전달함으로써 WEP키 등의 보안성이 요구되는 정보의 유출을 막고, 무선구간의 보안성을 제공하기 위해 공개키를 이용한 방안을 제시하고자 한다.

• Asian Journal of Atmospheric Environment
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• 제3권1호
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• pp.52-58
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• 2009

Airborne particulates were collected in three different size fractions (>7 ${\mu}m$; 2.1-7 ${\mu}m$; < 2.1 ${\mu}m$) by using Andersen low-volume air samplers at three sites in Tieling city, Liaoning Province, a typical local city in northeast China, in every season during the period from July 2003 to May 2004. Nine polycyclic aromatic hydrocarbons (PAHs) and seven nitropolycyclic aromatic hydrocarbons (NPAHs) in the airborne particulates were determined by HPLC with fluorescence and chemiluminescence detection, respectively. The mean total concentrations of the nine PAHs and seven NPAHs were highest at The mixed residential and light industrial site, and lowest at the residential site near the suburbs. At all sites, more than 70% of the total PAHs and more than 60% of the total NPAHs were found in the finest particulate (< 2.1 ${\mu}m$) fraction. Both cluster analysis and several diagnostic ratios showed that the major contributors of PAHs and NPAHs in airborne particulates were coal combustion systems such as domestic stoves and coal boilers in all seasons in Tieling city.

• 한국수산과학회지
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• 제8권3호
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• pp.166-170
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• 1975

시판되고 있는 6종의 어단 통조림을 수집하며 조직화학적 방법으로 분석한 결과를 요약하면 다음과 같다. 1. 단백질 함량은 일반적으로 낮았으며 $2.7\~8.9\%$의 함량을 보였고, 지방은 시료에 따라서 매우 변화가 심한 $1.4\~17.6\%$이었다. 3. 탄수화물은 약 $58.1\~75.2\%$로서 가장 높은 함량을 보였다. 3. 공포는 $14.4\~21.1\%$ 로서 많은 편이었다. 4. $37^{\circ}C$에서 4일간 배양한 시료 어단에서는 주로 전분, 단백질 및 공포주위에서 미생물이 집락을 형성하고 있는 것이 관찰되었다. 3. 이상을 종합할 때 수산연제품의 일종인 통조림 어단의 품질은 조직화학적 및 형태학적 방법으로 충분히 평가할 수 있는 것으로 판단된다. 끝으로 본실험을 위하여 지도하여 주신 전북대학교 예방의학교실 이 재구 박사 및 실험을 도와 주신 동교실 김 수명씨에게 사의를 표하는 바이다.

• Ocean and Polar Research
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• 제37권3호
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• pp.211-223
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• 2015

Korean society has been recently promoting the restoration of coastal wetlands. These efforts might become the basis of a policy framework that compensates for the limitations of a regulation-oriented policy such as the designation of Marine Protected Areas (MPAs). The shift in government policy could contribute to strengthening the socioeconomic infrastructure of coastal development through the accumulation of ecological capital. Although our scientific efforts and social demands in regard to the ecological restoration of the coastal wetlands have increased during the past years, the bases for restoration in Korea requires that scientific, technological, financial, social and legal aspects be enhanced. The present study re-examined the concept and attitudes behind coastal wetland restoration in the light of changing circumstances in Korea. Herein, we first defined coastal wetland restoration as "An act of recovering the functions of the ecosystem of coastal wetlands to a state that resembles conditions prior to being damaged." Next, this study discussed the limitations and future directions of such restoration efforts based on the descriptive analyses of recent restoration practices from social, economic, and technological aspects. Finally, we suggest future policy directions regarding coastal wetland restoration on the basis of a PFST (Policy, Financial, Social, and Technological) analysis; 1) re-arranging legal mechanisms, 2) setting multi-dimensional restoration goals, 3) establishing a multi-discipline- and convergence based R&D system, 4) linking spatial management and local development to the restoration, 5) building restoration governance at the local level, 6) implementing an ecosystem service payment system, and 7) applying test-bed projects in accordance with proper directions.