• 천문학회지
• /
• 제41권6호
• /
• pp.173-180
• /
• 2008

Using the MHD coronal seismology technique, we estimated the magnetic field for three spicules observed in 2008 June. For this study, we used the high resolution Ca II H line ($3968.5\;{\AA}$) images observed by the Hinode SOT and considered a vertical thin flux tube as a spicule model. To our knowledge, this is the first attempt to estimate the spicule magnetic field using the Hinode observation. From the observed oscillation properties, we determined the periods, amplitudes, minimum wavelengths, and wave speeds. We interpreted the observed oscillations as MHD kink waves propagating through a vertical thin flux tube embedded in a uniform field environment. Then we estimated spicule magnetic field assuming spicule densities. Major results from this study are as follows : (1) we observed three oscillating spicules having durations of 5-7 minutes, oscillating periods of 2-3 minutes, and transverse displacements of 700-1000 km. (2) The estimated magnetic field in spicules is about 10-18 G for lower density limit and about 43-76 G for upper density limit. (3) In this analysis, we can estimate the minimum wavelength of the oscillations, such as 60000 km, 56000 km, and 45000 km. This may be due to the much longer wavelength comparing with the height of spicules. (4) In the first event occurred on 2008 June 03, the oscillation existed during limited time (about 250 s). This means that the oscillation may be triggered by an impulsive mechanism (like low atmospheric reconnection), not continuous. Being compared with the ground-based observations of spicule oscillations, our observation indicates quite different one, i.e., more than one order longer in wavelength, a factor of 3-4 larger in wave speed, and 2-3 times longer in period.

• 과학교육연구지
• /
• 제33권2호
• /
• pp.304-316
• /
• 2009

교사 양성 과정에서 현장교육 프로그램은 예비교사들에게 교육활동을 경험하도록 함으로 올바른 교육관을 형성하고 신념의 변화를 가져오게 하는 중요한 기회를 제공해 준다. 이에 본 연구는 참관수업과 교육실습의 현장교육 프로그램이 예비과학교사들의 인식론적 교육관의 변화에 어떠한 영향을 미치는지 살펴보았다. 이를 위해 예비과학교사들을 대상으로 참관수업과 교육실습 기간에 따라 3차례 설문조사와 면담을 실시하였으며 모든 설문조사에 참여한 28명의 응답에 대해 결과를 분석하였다. 연구결과 예비과학교사들은 참관수업 전 전통적인 교육관인 객관주의 인식론적 교육관이 형성되어 있었으나, 참관수업과정에서 관찰한 현장교사의 영향으로 객관주의 인식론적 교육관이 다소 강해 진 것으로 나타났다. 그러나 교육실습과정에서 직접 수업에 참여해 봄으로써 현대적인 교육관인 구성주의 인식론적 교육관으로 유의미하게 변한 것으로 나타났다. 이에 현장교육 프로그램이 예비과학교사들의 교육관 변화에 긍정적 또는 부정적인 영향을 미칠 수 있음을 확인할 수 있었다. 따라서 예비과학교사들이 현장교육 프로그램을 통해 구성주의 인식론적 교육관을 획득하거나 강화시킬 수 있는 기회를 제공하기 위해 교사 양성기관과 학교 현장과의 유기적이고 지속적인 협력 체제를 마련해야 할 것이다.

• 대기
• /
• 제28권3호
• /
• pp.263-272
• /
• 2018

The high-resolution ocean surface wind vector produced by scatterometer was assimilated within the Local Ensemble Transform Kalman Filter (LETKF) in Korea Institute of Atmospheric Prediction Systems (KIAPS). The Advanced Scatterometer (ASCAT) on Metop-A/B wind data was processed in the KIAPS Package for Observation Processing (KPOP), and a module capable of processing surface wind observation was implemented in the LETKF system. The LETKF data assimilation cycle for evaluating the performance improvement due to ASCAT observation was carried out for approximately 20 days from June through July 2017 when Typhoon Nepartak was present. As a result, we have found that the performance of ASCAT wind vector has a clear and beneficial effect on the data assimilation cycle. It has reduced analysis errors of wind, temperature, and humidity, as well as analysis errors of lower troposphere wind. Furthermore, by the assimilation of the ASCAT wind observation, the initial condition of the model described the typhoon structure more accurately and improved the typhoon track prediction skill. Therefore, we can expect the analysis field of LETKF will be improved if the Scatterometer wind observation is added.

• 한국농공학회지
• /
• 제39권4호
• /
• pp.64-74
• /
• 1997

The purpose of this study is to analyze hydraulic characteristics of surface irrigation in a paddy field of direct seeding culture. Field experiment was performed in the paddy field of ridge direct dry seeding. Simulation by a numerical model was also accomplished with the data obtained from the field experiment. The model was developed by one dimensional zero-inertia equation and finite difference method. From the result of the field observation, the furrows of the experimental field were found to have various geometric characteristics. Advance distance and time were measured both in the field and by the model simulation for various furrow lengths and irrigation discharges. Roughness coefficients of each furrow were also estimated by the model.

• 대한약침학회지
• /
• 제14권3호
• /
• pp.19-45
• /
• 2011

Objectives: This study was performed to analyse the effects of Sweet Bee Venom(Sweet BV-pure melittin, the major component of honey bee venom) on the central nervous system in rats. Methods: All experiments were conducted at Biotoxtech Company, a non-clinical studies authorized institution, under the regulations of Good Laboratory Practice (GLP). Male rats of 5 weeks old were chosen for this study and after confirming condition of rats was stable, Sweet BV was administered in thigh muscle of rats. And checked the effects of Sweet BV on the central nervous system using the functional observational battery (FOB), which is a neuro-toxicity screening assay composed of 30 descriptive, scalar, binary, and continuous endpoints. And home cage observations, home cage removal and handling, open field activity, sensorimotor reflex test/physiological measurements were conducted. Results: 1. In the home cage observation, there was not observed any abnormal signs in rats. 2. In the observation of open field activity, the reduction of number of unit areas crossed and rearing count was observed caused by Sweet BV treatment. 3. In the observation of handling reactivity, there was not observed any abnormal signs in rats. 4. In the observation of sensorimotor reflex tests/physiological measurements, there was not observed any neurotoxic signs in rats. 5. In the measurement of rectal temperature, treatment of Sweet BV did not showed great influences in the body temperature of rats. Conclusions: Above findings suggest that Sweet BV is relatively safe treatment in the central nervous system. But in the using of over dose, Sweet BV may the cause of local pain and disturbance of movement. Further studies on the subject should be conducted to yield more concrete evidences.

• International Journal of Advanced Culture Technology
• /
• 제10권4호
• /
• pp.126-136
• /
• 2022

The purpose of this study is to investigate the application experience and observation of young children's teachers' digital devices. The participants of this study were 6 young children teachers using digital devices. Individual interviews were conducted as a data collection method. It was conducted 2-3 times per research participant. Data collection was conducted from November to December 2020. The Data analysis was focused on the young children's teachers' digital device application experience and observation use. 'Easy and simple use', 'using existing familiar apps', 'providing healing to teachers', and 'improving the utilization of spare time' were derived as early childhood teachers' experience of applying digital devices. 'Easy use of observation records', 'Use together in various ways', 'Use for parent counseling', 'Use appropriate for observation of revised Nuri Curriculum' through early childhood teacher's experience of observing digital devices ' was derived. As a conclusion of this study, first, it is easy for young children's teachers to apply digital devices to the field. Second, if young children's teachers use digital devices, they can make a wide range of observations, enabling high-quality early childhood education practices.

• 한국정보통신학회논문지
• /
• 제8권3호
• /
• pp.645-653
• /
• 2004

수중 어류의 행동이나 현상을 예측하여 시각화하기 위해서는 어류의 탐지와 어류반응행동의 파악이 우선 이루어져야 한다. 수중이라는 다변적인 환경요인이 현장 계측을 매우 어렵게 하거나 어류의 행동이 비선형적으로 복잡하고 혼돈스러우므로 기존의 단순한 그래픽처리는 실제 수중현상간의 차이를 극복하지 못해왔던 실정이다. 이에 본 논문에서는 매우 복잡 다양한 어류행동반응의 패턴에 대하여 기존의 연구에서 제안된 혼돈이론을 응용한 어류반응행동 모델을 이용하여 시각화 도구를 제안함으로써 수중의 어류이동현상을 예측하거나 평가, 또는 보다 더 정확히 분석하는 자료를 얻을 수 있게 구현하였다. 아울러, 어탐 디스플레이를 동시에 적용하여 사용자에게 반응에 따르는 어류의 탐지상황도 제공하였다. 제안된 시각화 도구를 평가하기 위하여 현장 계측된 어류의 이동 정보와 비교한 결과, 제안된 시각화 도구는 사실성 높은 어류 행동과 시각적인 이해도를 높일 수 있음을 확인 할 수 있었다.

• 대기
• /
• 제33권3호
• /
• pp.319-330
• /
• 2023

As the need for PM type observation increases, Surface Particulate Matter Network (SPARTAN), PM samplers analyzes aerosol samples for PM mass concentration and chemical composition, were recently installed at two sites: Yonsei University at Seoul and Ulsan Institute of Science and Technology (UNIST) at Ulsan. These SPARTAN filter samplers and nephelometers provide the PM_2.5 mass concentration and chemical speciation data with aerosol type information. We introduced the overall information and installation of SPARTAN at the field site in this study. After installation and observation, both Seoul and Ulsan sites showed a similar time series pattern with the daily PM_2.5 mass concentration of SPARTAN and the data of Airkorea. In particular, in the case of high concentrations of fine particles, daily average value of PM_2.5 was relatively well-matched. During the Yonsei University observation period, high concentrations were displayed in the order of sulfate, black carbon (BC), ammonium, and calcium ions on most measurement days. The case in which the concentration of nitrate ions showed significant value was confirmed as the period during which the fine dust alert was issued. From the data analysis, SPARTAN data can be analyzed in conjunction with the existing urban monitoring network, and it is expected to have a synergetic effect in the research field. Additionally, the possibility of being analyzed with optical data such as AERONET is presented. In addition, the method of installing and operating SPARTAN has been described in detail, which is expected to help set the stage for the observation system in the future.

• 한국초등과학교육학회지:초등과학교육
• /
• 제21권2호
• /
• pp.241-252
• /
• 2002

Field learning have not well performed in elementary school for various reasons, in spite of the benefits of field study. Absence of suitable geological field courses for elementary science education is one of several reasons The purpose of this study is to develop learning materials for the field geology in Hampyeong region and apply them to the geological related units for elementary science education. The 5 observation sites for the field geology learning in study area include various rocks and geological structure such as granite, gneiss, conglomerate, sandstone, mudstone, plant fossil, fold, fault and weathering phenomenon changing rocks to soil. This study area is suitable place for the field geology learning of elementary science education in Kwangju and Chonnam province because of convenience access, fresh outcrops and distribution of various geological learning materials as rocks and structure.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2006년도 춘계 학술발표회 논문집
• /
• pp.916-924
• /
• 2006

This research concentrates on presenting a more reasonable and engineering tunnel interpretation method with the numerical value observation data using the Hoek-Brown Model that uses mining observation data gained during construction, and the experience material constant of m and s for Seoul Underground tunnel field, which was evaluated as RMR III and RMR IV for its bedrock ratings, and by modifying and complementing the properties of ground materials with the direct method, one method in back analysis, and by using the field measurement value.