• 한국작물학회:학술대회논문집
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• 한국작물학회 2005년도 국제학술회의
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• pp.22-46
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• 2005

Spatial and timely information on crop and filed conditions is one of the most important basics for rational and efficient planning and management in agriculture. Remote sensing, GIS, and modeling are powerful tools for such applications. This paper presents an overview of the state of the art in remote sensing of crop and field conditions with some case studies. It is also shown that a synergistic linkage between process-based models and remote sensing signatures enables us to estimate the multiple crop/ecosystem variables at a dynamic mode. Remotely sensed information can greatly reduce the uncertainty of simulation models by compensating for insufficient availability of data or parameters. This synergistic approach allows the effective use of infrequent and multi-source remote sensing data for estimating important ecosystem variables such as biomass growth and ecosystem $CO_2$ flux. This paper also shows a geo-spatial information system that enables us to integrate, search, extract, process, transform, and calculate any part of the data based on ID#, attributes, and/or by river-basin boundary, administrative boundary, or boundaries of arbitrary shape/size all over Japan. A case study using the system demonstrates that the nitrogen load from fertilizer was closely related to nitrate concentration of groundwater. The combined use of remote sensing, GIS and modeling would have great potential for various agro-ecosystem applications.

• 한국군사과학기술학회지
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• 제24권5호
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• pp.545-557
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• 2021

Engine is the main source of vibration that generates unwanted noise and vibration of vehicle chassis. Especially, in submarine applications, radiation of noise signatures can be detected at some distance away from the submarine using a sonar array. Thus quiet operation is crucial for submarine's survivability. This study addresses reduction of the force transmissibility originating from engines and transmitted to hull through engine mounts. An inertial damper, as an actuator of hybrid mount system, is addressed to reduce even further the level of vibration. Narrow band FxLMS algorithms are broadly used to cancel the vibration of engine mount because of its excellent performance of canceling narrow band noise. However, in real active dampers, the maximum displacement of damper mass is kinematically restricted. When the control input signal from the FxLMS algorithm exceeds this limitation, the damper mass will collide with the mechanical stops and results in many problems. Originated from these, a modified narrow band FxLMS algorithm based on the equalizer technique with the maximum allowable displacement of active damper mass is proposed in this study. Some simulation results showed that the propose algorithm is effective to suppress vibration of engine mount while ensuring given displacement constraint.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권2호
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• pp.1003-1019
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• 2019

Threshold ring signature scheme enables any t entities from N ring members to spontaneously generate a publicly verifiable t-out-of-N signature anonymously. The verifier is convinced that the signature is indeed generated by at least t users from the claimed group, but he cannot tell them apart. Threshold ring signatures are significant for ad-hoc groups such as mobile ad-hoc networks. Based on the lattice-based ring signature proposed by Melchor et al. at AFRICRYPT'13, this work presents a lattice-based threshold ring signature scheme, employing the technique of message block sharing proposed by Choi and Kim. Besides, in order to avoid the system parameter setup problems, we proposed a message processing technique called "pad-then-permute", to pre-process the message before blocking the message, thus making the threshold ring signature scheme more flexible. Our threshold ring signature scheme has several advantages: inherits the quantum immunity from the lattice structure; has considerably short signature and almost no signature size increase with the threshold value; provable to be correct, efficient, indistinguishable source hiding, and unforgeable.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 춘계학술대회
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• pp.110-110
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• 2022

Rice is the world's most important food crop and a major source of nutrition for about two thirds of populations. Northern Vietnam is one of the most important centers of genetic diversity for cultivated rice. In this study, we determined the genetic diversity and population structure of 79 rice landraces collected from northern Vietnam and 19 rice accessions collected from different countries. In total, 98 rice accessions could be differentiated into japonica and indica with moderate genetic diversity and a polymorphism information content of 0.382. We also detected subspecies-specific markers to classify rice (Oryza sativa L.) into indica and japonica. Additionally, we detected five marker-trait associations and rare alleles that can be applied in future breeding programs. Most interestingly, analysis of molecular variance (AMOVA) found genetic differentiation was related to geographical regions with an overall PhiPT (analog of fixation index FST) value of 0.130. More emphasis was given to provide signatures and infer explanations about the role of geographical isolation and environmental heterogeneity in genetic differentiation among regions in landraces from northern Vietnam. Our results suggest that rice landraces in northern Vietnam have a dynamic genetic system that can create different levels of genetic differentiation among regions, but also maintain a balanced genetic diversity between regions.

• Asian Pacific Journal of Cancer Prevention
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• 제14권3호
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• pp.1851-1863
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• 2013

Diurnal variation of particulate polycyclic aromatic hydrocarbons (PAHs) was investigated by collecting PM10 at three different sampling altitudes using high buildings in the city center of Chiang-Mai, Thailand, during the relatively cold period in late February 2008. At site-1 (12 m above ground level), B[a]P concentrations ranged from 30.3-1,673 pg $m^{-3}$ with an average of $506{\pm}477\;pg\;m^{-3}$ contributing on average, $8.09{\pm}8.69%$ to ${\Sigma}PAHs$. Ind and B[b]F concentrations varied from 54.6 to 4,579 pg $m^{-3}$ and from 80.7 to 2,292 pg $m^{-3}$ with the highest average of $1,187{\pm}1,058\;pg\;m^{-3}$ and $963{\pm}656\;pg\;m^{-3}$, contributing on average, $19.0{\pm}19.3%$ and $15.4{\pm}12.0%$ to ${\Sigma}PAHs$, respectively. Morning maxima were predominantly detected in all observatory sites, which can be described by typical diurnal variations of traffic flow in Chiang-Mai City, showing a morning peak between 6 AM. and 9 AM. Despite the fact that most monitoring sites might be subjected to specific-site impacts, it could be seen that PAH profiles in Site-1 and Site-2 were astonishingly homogeneous. The lack of differences suggests that the source signatures of several PAHs become less distinct possibly due to the impacts of traffic and cooking emissions from ground level.

• 암석학회지
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• 제14권4호
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• pp.226-236
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• 2005

이 연구에서는 화강암 스위트와 슈퍼스위트의 개념을 사용하여 우리나라 트라이아스기 화강암을 대상으로 시공간적으로 밀접하게 관련된 화강암체들을 계층적으로 구분하였다. 옥천대(서부 영남육괴)의 트라이아스기 화강암 중에서 백록화강암과 점촌화강암은 하나의 백록 스위트로 지정되며, 청산 화강암은 청산스위트로 지정된다. 이 두 스위트는 근원물질의 유사성과 기재적 및 지구화학적 상이성 등으로부터 하나의 슈퍼스위트, 즉 백록 슈퍼스위트로 묶을 수 있다. 경상분지의 트라이아스기 화강암인 영덕화강암, 영해화강암, 청송화강암은 각각 독립적인 영덕 스위트, 영해 스위트, 청송 스위트로 지정된다. 이 세 스위트는 근원물질의 유사성과 기재적 및 지구화학적 상이성 등으로부터 하나의 슈퍼스위트, 즉 영덕 슈퍼스위트로 묶을 수 있다. 서부 영남육괴의 백록 슈퍼스위트와 경상분지의 영덕 슈퍼스위트는 Nd-Sr 동위원소 특징에서 아주 뚜렷한 차이를 보이는데, 이는 두 슈퍼스위트를 만든 화강암질 마그마의 근원물질이 서로 달랐음을 지시한다. 백록 슈퍼스위트는 그 근원물질이 영남육괴를 이루는 지각물질들 사이의 혼합으로 설명되는 반면, 영덕 슈퍼스위트의 근원물질은 결핍된 맨틀과 영남육괴 지각물질의 혼합으로 설명된다. 동시기 화성활동의 산물인 백록 슈퍼스위트와 영덕 슈퍼스위트에서 화강암질 마그마의 근원물질에 차이를 보이는 것은 마그마 생성의 장소가 지체구조적으로 상이하였음을 지시하는 것이다.

• Asian Journal of Atmospheric Environment
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• 제6권2호
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• pp.83-95
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• 2012

China has been a top producer and exporter of refined lead products in the world since the year 2000. After the phasing-out of leaded gasoline in the late 1990s, non-ferrous metallurgy and coal combustion have been identified as potential major sources of aerosol lead in China. This paper presents the single particle analytical results of ambient aerosol particles collected near a lead smelter using a scanning electron microscopy- energy dispersive x-ray spectroscopy (SEM-EDX). Aerosol particle samples were collected over a 24-hour period, starting from 8 pm on 31 May 2002, using a high volume TSP sampler. For this near source sample, 73 particles among 377 particles analyzed (accounting for 19.4%) were lead-containing particles mixed with other species (S, Cl, K, Ca, and/or C), which probably appeared to be from a nearby lead smelter. Lead-containing particles of less than $2{\mu}m$ size in the near source sample were most frequently encountered with the relative abundances of 42%. SEM-EDX analysis of individual standard particles, such as PbO, PbS, $PbSO_4$, $PbCl_2$, and $PbCO_3$, was also performed to assist in the clear identification of lead-containing aerosol particles. Lead-containing particles were frequently associated with arsenic and zinc, indicating that the smelter had emitted those species during the non-ferrous metallurgical process. The frequently encountered particles following the lead-containing particles were mineral dust particles, such as aluminosilicates (denoted as AlSi), $SiO_2$, and $CaCO_3$. Nitrate- and sulfate-containing particles were encountered frequently in $2-4{\mu}m$ size range, and existed mostly in the forms of $Ca(NO_3,SO_4)/C$, $(Mg,Ca)SO_4/C$, and $AlSi+(NO_3,SO_4)$. Particles containing metals (e.g., Fe, Cu, and As) in this near source sample had relative abundances of approximately 10%. Although the airborne particles collected near the lead smelter contained elevated levels of lead, other types of particles, such as $CaCO_3$-containing, carbonaceous, metal-containing, nitrates, sulfates, and fly-ash particles, showed the unique signatures of samples influenced by emissions from the lead smelter.

• 자원환경지질
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• 제39권5호
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• pp.555-566
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• 2006

주성분원소, 미량원소 및 희토류원소에 대한 지화학적 연구를 통하여 진동화강암의 성인과 마그마 근원물질의 지화학적특징 및 지구조적 환경을 살펴보았다. 진동화강암은 비알칼리암 중에서 칼크-알칼리계열의 화강암류이며, 마그마의 특성이 metaluminous에서 분화가 진행됨에 따라 peraluminous한 쪽으로 진행됨을 알 수 있다. 이들의 주성분 및 미량원소의 변화경향은 체계적인 연속성을 나타내며, 콘드라이트에 표준화한 희토류원소의 패턴은 일반적으로 경희토류원소가 부화되어 나타나며((La/Yb)c=4.2-12.8), Eu의 이상이 거의 나타나지 않는다. 진동화강암체의 Rb-Sr전암연대는 $114.6{\pm}9.1\;Ma$이며 $^{87}Sr/^{86}Sr$의 초생값은 0.70457로 나타났다. 낮은 $^{87}Sr/^{86}Sr$의 초생값은 경상분지 남부의 마산, 김해, 부산지역에 분포하는 백악기 화강암류들($^{87}Sr/^{86}Sr=0.7049-0.707$)과 유사하다. 이는 진동화강암체의 관입시기가 경상분지내에 분포하는 백악기 화강암류 중에서 가장 오래된 백악기 초기였으며 근원물질이 상부맨틀과 관련이 있음을 지시한다. 진동화강암체는 경상분지내의 다른 백악기 화강암류에 비해 상대적으로 높은 $Al_{2}O_{3},\;Na_{2}O$ 및 Sr과 낮은 $K_{2}O$와 Y의 함량을 보인다. 이들의 주성분원소($Al_{2}O_{3},\;K_{2}O,\;Na_{2}O,\;MgO$) 및 미량원소(Sr, Y, Rb) 함량범위는 adakite의 범주에 포함되며 남서부 일본의 큐슈(Kyushu)섬에서 나타나는 화강암체와 유사한 adakitic한 지화학적 특성을 나타낸다. 지구조 판별도 및 AUK vs. ACNK도에 점시해본 결과 I-type의 화강암으로 지구조적 환경은 화산호화 강암(VAG) 영역에 해당된다. 이 결과로 미루어 진동화강암류는 중생대 백악기 이자나기판의 섭입과 관련되어 관입한 대륙주변부 환경에서 생성되었음을 시사한다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권5호
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• pp.2427-2445
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• 2016

In contrast to traditional "store-and-forward" routing mechanisms, network coding offers an elegant solution for achieving maximum network throughput. The core idea is that intermediate network nodes linearly combine received data packets so that the destination nodes can decode original files from some authenticated packets. Although network coding has many advantages, especially in wireless sensor network and peer-to-peer network, the encoding mechanism of intermediate nodes also results in some additional security issues. For a powerful adversary who can control arbitrary number of malicious network nodes and can eavesdrop on the entire network, cryptographic signature schemes provide undeniable authentication mechanisms for network nodes. However, with the development of quantum technologies, some existing network coding signature schemes based on some traditional number-theoretic primitives vulnerable to quantum cryptanalysis. In this paper we first present an efficient network coding signature scheme in the standard model using lattice theory, which can be viewed as the most promising tool for designing post-quantum cryptographic protocols. In the security proof, we propose a new method for generating a random lattice and the corresponding trapdoor, which may be used in other cryptographic protocols. Our scheme has many advantages, such as supporting multi-source networks, low computational complexity and low communication overhead.

• 지구물리와물리탐사
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• 제8권1호
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• pp.97-103
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• 2005

여러 센서들의 배열을 이용한 최근의 해양 자력구배 측정시스템의 개발을 통하여 넓은 오염지역의 조사를 빠르게 수행할 수 있게 되었다. 그러나 물밑의 UXO 는 조류에 의해 이동할 수 있으며 따라서 이런 환경에서의 복원과정은 정적이라기 보다는 동적이 되었다. 이는 곧 성공적인 복원을 위해서는 탐지가 거의 실시간으로 이루어져야 함을 말한다. 그러므로 해양 자력탐사자료로부터 물밑 물체의 신호를 빠르게 탐지할 수 있는 신속한 해석법이 필요하다. 이 논문에서는 물밑 UXO 의 위치 및 특성을 알아내는 신속한 방법을 소개하였다. 먼저 대상체의 정밀 탐지를 위해 자력구배자료의 해석기법(해석적 신호와 Euler 방법)을 이용하며, 반복적 선형 최소자승법을 이용해 대상체의 자기 특성을 얻어낸다. 이 방법은 알고 있는 대상체에 대해 무작위 잡음을 더한 이론적 해양 자력이상에 적용되었으며, 일본의 해양 자력구배탐사 자료를 이용하여 실질적인 유용성을 예시하였다.