• 분석과학
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• 제13권1호
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• pp.12-21
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• 2000

PIGE(양성자유발 감마선발생) 분석법을 이용하여 Li~K에 이르는 경원소의 분석을 시도하였다. 각 원소별로 표준시료를 제작하여 사용하는 방법으로 지질 및 생체, 환경, 소재 등 다양한 시료를 시험분석하였다. 양성자 에너지 2.4 MeV와 3.4 MeV에 대하여 측정하였으며 일반적으로 다중원소 검출시 3.4 MeV가 유리한 것으로 나타났다. 분석결과는 표준치와 최대 15%내로 일치하였다. 검출한계는 Li, B, F, Na의 경우 100 ppm 이내, 기타 원소들은 수백 ppm ~ 수%로 계산되었다.

• Applied Biological Chemistry
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• 제22권4호
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• pp.217-220
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• 1979

요소(尿素)를 첨가(添加)한 토양(土壞)과 첨가(添加)하지 않은 토양(土壞)에 함질소(含窒素) 제초제(除草劑) asulam, dimetametryne, linuron을 처리(處理)하여 $25^{\circ}{\pm}1^{\circ}C$에서 항온배양(恒溫培養)하면서 효소(酵素) urease activity의 변화(變化)를 경시적(經時的)으로 검사(檢討)하였던 바 다음과 같은 결과(結果)를 얻었다. 요소(尿素)를 첨가(添加)하지 않은 토양(土壤)에서 dimetametryne 및 linuron 약제(藥劑) 처리(處理)에서는 urease의 활성(活性)이 상당히 높았으며, 배양기간(培養期間)이 경과(經過)하면서 약제처리(藥劑處理) 농도(濃度)가 높음에 따라 효소활성(酵素活性)이 다소(多少) 높게 지속(持續)되어 갔다. 반면(反面) 요소(尿素)를 첨가(添加)한 토양(土壤)에서는 asulam과 dimetametryne 약제(藥劑)에 의(依)해서는 효소활성(酵素活性)이 상당히 억제되었으나 linuron 약제(藥劑)는 이와 다르게 요소단독처리구(尿素單獨處理區)보다 다소(多少) 높은 효소활성(酵素活性)을 보였다.

• 한국토양비료학회지
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• 제18권4호
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• pp.352-358
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• 1985

1~0.5mm모래로 충전(充塡)한 sand column을 통해서 Zeolite가 수직(垂直) 유실(流失)과 수리전도도의 변화(變化)에 미치는 양이온의 영향(影響)을 조사(調査)한 결과(結果)는 다음과 같다. 1. Zeolite의 유실량(流失量)의 정도(程度)는 Na->K->$NH_4-$ Zeolite 순이었고 Mg-과 Ca-Zeolite는 유실(流失)되지 않았다. 2. Zeolite의 수직유실(垂直流失)은 주로 입자(粒子)들의 분산(分散)에 기인(基因)하였으며 투과용액(透過溶液)이 0.01N 농도(濃度)의 염용액(鹽溶液)에서 증류수(蒸溜水)로 바뀔때 분산(分散)이 가장 잘 일어났다. 3. 수리전도도(水理傳導度)의 변화(變化)가 심한 column 일수록 Zeolite 유실량(流失量)이 많았다.

• Human Ecology Research
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• 제62권2호
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• pp.249-259
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• 2024

The purpose of this study was to identify the longitudinal mediating effects of peer attachment on the relationship between psychological school environment and children's sense of community. Data on 1,088 children were obtained from the 10^th, 11^th, and 13^th Panel Study on Korean Children in the 3rd 4th, and 6th grades. The data were analyzed using descriptive statistics, Cronbach's α, Pearson's correlation, a latent growth model, and a multivariate latent growth model. All analyses were conducted in SPSS 25.0 and AMOS 23.0. The principal results were as follows. First, children's peer attachment gradually decreased over time. Moreover, individual differences existed in the initial values and rates of change. Second, the psychological school environment in the 3rd grade positively influenced children's initial peer attachment, which then exerted a positive impact on children's sense of community in the 6th grade. Second, the psychological school environment in the 3rd grade negatively influenced children's rates of change, which also exerted a positive impact on children's sense of community in the 6th grade. Finally, the initial value and rates of change of peer attachment were significant mediating effects of the relationship between the psychological school environment in the 3rd grade and children's sense of community in the 6th grade. The findings highlight the necessity of creating a psychological school environment that develops peer attachment and a sense of community among children.

• 아동학회지
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• 제26권5호
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• pp.205-216
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• 2005

This study investigated aspects of caregiver's input relating to the early development of nouns and verbs. Subjects were 34 Korean-Chinese children in Yanji, China. At 1 year of age each child's spontaneous speech during interaction with his/her caregiver was videotaped for about 30 minutes. The children's spontaneous utterances were transcribed and coded on the lexical level(nouns and verbs) and the pragmatic level. Children's speech was recorded, transcribed and coded again at 2 years of age. Results showed that children used more verbs when they were older; there were no differences between the two ages in mother's pragmatic utterances but when they were two-years-old children used more actionoriented utterances and object-described utterances. Mother's input was related to children's pragmatic utterances.

• 정보관리학회지
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• 제2권2호
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• pp.71-114
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• 1985

의학도서관에 있어 예산면이나 관리면에 가장 중점을 이루는 것이 학술잡지이다. 더욱이 대부분 외국학술지에 의존하고 있는 우리의 실정으로는 더욱 예산의 압박을 초래하고 있다. 그러므로 외국학술잡지의 협동수서를 위한 기초 조사로 중요 의학도서관들의 학술잡지 이용 실태를 조사하여 핵심 잡지군의 시간적, 기관적 차이를 알아보았고 각 의학도서관의 공통적 핵심잡지군등을 조사, 연구하였다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.1762-1765
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• 1997

Some ill-conditioned processes are very sensitive to small element-wise uncertainties arising in classical element-by-element model identifications. For such processes, accurate identification of simgular values and right singular vectors are more important than theose of the elements themselves. Singular values and right singular vectors can be found by iteraive identification methods which implement the input and output transformations iteratively. Methods based on SVD decomposition, QR decomposition and LU decomposition are proposed and compared with the Kuong and Mac Gregor's method. Convergence proofs are given. These SVD and QR mehtods use normal matrices for the transformations which cannot be calculated analytically in general and so they are hoard to apply to dynamic processes, whereas the LU method used simple analyitc transformations and can be directly applied to dynamic processes.

• 품질경영학회지
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• 제18권2호
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• pp.127-133
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• 1990

In this article, several problems inherent in histogram estimate of unknown probability density function are discussed. Those include so called sharp comers and bin edge effect. A resolution for these problems occurred with histogram is discussed. The resulting estimate is called kernel density estimate which is most widely used by data analysts. One of the most recent and reliable data-based choices of scale factor (bandwidth) of the estimate, which has been known to be most crucial, is also discussed.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVI)
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• pp.309-310
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• 2005

Bioconverted linolenic acid (bLNA) obtained from linolenic acid by Pseudomonas aeruginosa PR3, showed anti-fungal activity against plant pathogens such as B. cinerea, F. oxysporum, F. solani, P. capsici and C. capsici. The oil sample also showed anti-fungal activity with MIC values, ranging from >250 to >1,000 ${\mu}g/ml$. Varied concentrations of bLNA had a great potential effect on spore germination of different fungi.

• International Journal of Ocean System Engineering
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• 제2권4호
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• pp.223-232
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• 2012

For the accurate estimation of the position and orientation of a UUV (unmanned underwater vehicle), a low-cost AHRS (attitude heading reference system) was developed using a low-cost IMU (inertial measurement unit) sensor which provides information on the 3D acceleration, 3D turning rate and 3D earth-magnetic field data in the object coordinate system. The main hardware system is composed of an IMU sensor (ADIS16405) and TMS320F28335, which is coded with an extended kalman filter algorithm with a 50-Hz sampling frequency. Through an experimental gimbal device, good estimation performance for the pitch, roll, and yaw angles of the developed AHRS was verified by comparing to those of a commercial AHRS called the MTi system. The experimental results are here presented and analyzed.