• The Korean Journal of Applied Statistics
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• v.10 no.1
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• pp.15-27
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• 1997

Randomized block design (RBD) with three replication is very frequently adopted in agricultural experiments of the Rural Development Administration of Korea. Even though it works well in field trials of traditional crops, it may not accomodate trial site conditions and/or experimental environment. In this research report, we deal with two such cases. The first case is for a crop experiment in green houses. In house conditions, RBD may not be appropriate since it cannot reflect two directions of the yield gradient. So, a Latin square design is suggested as an alternative. The second case is for local field experiments of the newly-inbred rice. RBD with three replications is used without doubt for decades, even though the site layout is not appropriately shaped for the design. In this case, we suggest the RBD in two blocks with multiple replicates for control varieties as an alternative. To improve the quality of statistical experimental designs in over one-thousand agricultural trials performed annually in the Rural Development Administration, we need to re-train agricultural researchers on the design and analysis of experiments and call for concerns of Korean statisticians.

• The Journal of the Acoustical Society of Korea
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• v.12 no.3
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• pp.43-48
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• 1993

This study was carried out to verificate the possibility of using the laboratory setting psycho-acoustic experiment compared with the field and to delineate the appropriate indices in evaluating the Noisiness of road traffic noise by means of psycho-acoustic method. Reviewing the typical patterns of traffic noises depending upon the shapes ad conditions of the road, the road traffic noises in several representative points in the major residential areas in Kwangju city were recorded and reproduced with the noise levels modified in various steps. With these 20 sound sources, psycho-acoustic experiments in the laboratory were performed on 11 volunteer subjects. And then, psycho-acoustic experiments in the real field were performed on 10 volunteer subjects to compare the results of the laboratory experiment, the results are summerized as follows : 1. The psycho-acoustic experiments in the laboratory elicited the data well matching with those obtained in the field, resulting in even higher corelation levels. This indicates that the field assessement of responses to the noise can be replaced by the evaluatioin in the laboratory settings which render many variables easily controlled and that the responses of the residents to the noise can be easily predicted in the laboratory by applying this method. 2. Also among the complex indices, such as Noise Pollution Level or Annoyance Index high correlations were detected. On the other hand, low corelations were noted among Traffic Noise Index. 3. Highly significant correlations were found among the direct indices such as Leq, L\sub 10\, On the other hand, low correlations were detected among L\sub 50\.

• Journal of the Korean Data and Information Science Society
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• v.14 no.2
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• pp.201-208
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• 2003

Since no information about the optimum plot sizes on field experiments on the major food crops in Korea is available, present status of plot sizes being used by the research institutes was examined for rice, barley & wheet, soybean, potatoes, red pepper, garlic and onion. The optimum plot sizes in field experiments on these crops were estimated on the basis of soil fertility indices (Smith's regression coefficients) that Chang (1983) reported.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11a
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• pp.365.2-365
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• 2002

The flow field around a symmetrical airfoil in a uniform flow under the generation of noise was studied by experiments and numerical simulation. The experiments are conducted by visualizing the surface flow over the airfoil with a shear-sensitive liquid-crystal coating and by measuring the instantaneous velocity field around the trailing edge of the airfoil. The numerical simulation was carried out by LES. (omitted)

• Progress in Superconductivity and Cryogenics
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• v.13 no.1
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• pp.46-50
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• 2011

The electrical insulation design of high voltage superconducting fault current limiters (SFCLs) should be confirmed to be applied for the stabilization of the power grid. This paper describes numerical analysis and AC dielectric experiments for developing high voltage SFCLs. The electric field distributions between applied high voltage part and ground were calculated by finite element method (FEM) simulation tool and AC criterion of liquid nitrogen at 200 kPa was calculated from correlation between the field utilization factor and FEM simulation results. This paper deals with ceonceptual insulation design of a 154 kV class single-phase no-inductively wound solenoid type SFCL which was focused on gap distance between the cryostat and superconducting coils. Furthermore, the shield ring effect was confirmed to reduce maximum electric field at applied high voltage part.

• Journal of Magnetics
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• v.22 no.2
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• pp.326-332
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• 2017

The effects of exposure to an extremely low-frequency magnetic field (25 Hz 20G) on animal cells have been studied. In some reports, stimulation was performed for fixed frequency and variations in magnitude; however, animal-cell experiments have established that both parameters play an important role. The present work undertook the modeling, simulation, and development of a uniform-magnetic-field generation system with variable frequency and stimulation intensity (0-60 Hz, 1-25G) for experimentation with cell cultures in situ. The results showed a coefficient of variation less than 1 % of the magnetic-field dispersion at the working volume, which is consistent with the corresponding simulation results demonstrating a uniform magnetic field. On the other hand, long-term tests during the characterization process indicated that increments of only $0.4^{\circ}C$ in the working volume temperature will not be an interfering factor when experiments are carried out in in situ cell cultures.

• Proceedings of the CALSEC Conference
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• 2003.09a
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• pp.167-171
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• 2003

목차 ◎연구의 배경 ㆍ전통적인 교육과 온라인 교육 ◎효과적 온라인 교육：능동적 체험 학습 ◎가상현장교육(Virtual Field Education) ㆍ가상현장교육 환경 및 구성 ㆍ지식의 전달 및 학습 과정 ◎가상현장실험(Virtual Field Experiments) ◎정보통신 교육과 연구의 융합(중략)

• Journal of the Korean Society of Environmental Restoration Technology
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• v.2 no.1
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• pp.72-82
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• 1999

The objective of this study was to covering of vine the traffic noise barrier and analyse of their growth characteristics. For the purpose of the experiments, chosen were 28 plants. In January 1996 to December 1998, the nursery seedbeds on the Chonju Arboretum in Korea Highway Corporation were seeding and cutting with those species, and a few species were carried out Honam Highway field experiments. The results are summarized as follows ; The germination ratio of seedbed experiments were Wisteria floribunda(88%), Lonicera japonica(86%), Parthenocissus tricuspidata, Paederia scandens(85%), Celastrus orbiculatus(76%), Clematis terniflora var. denticulata(52%), Clematis mandshurica(44%) respectively. The rooting ratio of cutting experiments were Trachelospermum asiaticum var. intermedium(88%), Parthenocissus quinquefolia(87%), Trachelospermum asiaticum var. asiatica(85%), Kadsura japonica(82%), Hedera rhombea(81%), Euonymus fortunei var. radicans(83%), Trachelospermum jasminoides var. pubescens(80%), Lonicera japonica cv. Aureo-reticulata(80%), Trachelospermum asiaticum var. majus(78%), Euonymus radicans cv. Aureo-marginata(66%), in descending order. As a conclusion, this study shows that the traffic noise barrier was effected by Paederia scandens, Lonicera japonica, Parthenocissus quinquefolia, Wisteria floribunda, Parthenocissus tricuspidata in the field experiments and the others were necessary to maintainable management.

• Journal of The Korean Association For Science Education
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• v.9 no.2
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• pp.29-45
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• 1989

The purpose of this paper is to study the operational skills of apparatuses in observation and experiments a point of view of the teaching-learning guidance of the middle school science. In order to understand the actual condition of the field learner, the achivment levels of learner have been investigated on the operational skills of apparatuses, observation and experiments through 1120 students of 16 middle schools. The results showed that there were large differences at each item and especially, in animate natural part(physics and chemistry), the handling ability was very low to average 33 percentage. By the result of analyzing the actual condition of the experiment and field science from the question of 114 science teachers who work in 40 middle schools in P distriet. it has been recognized that though the lessons through the experiments stimulate the motivation of learning, it couldn't be mamaged efficently because of all the educational conditions. And it was revealed that the major part of Experiment was performed not by student who is subjective in the course of learning but by teacher through experiments.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.12 no.1
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• pp.84-91
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• 2001

In in vitro cell experiments for the biological assessment of electromagnetic (EM) field, exposure system (ES) must be analyzed in terms of current density (J) and induced electric field intensity (E). Although in uniform B field, E and J in the sample medium are not distributed uniformly because of conductivity in sample dish. Thus, the precise estimation for E and J induced by uniform ELF within sample media is very important keys for successful in in vitro experiments. In this paper, we designed in vitro ELF ES with electromagnetic analysis using MATLAB simulator. Then we calculated from the measured B field to verify induced E & J distribution for random locations of cells within media in two cases of samples existence or not. ES with B field ranging from 0 to 20G consists of Helmholz coil and current generator based on the microprocessor. Also, we developed ELFES for each B field generation as uniform and non-uniform modes.