• Mycobiology
• /
• v.35 no.2
• /
• pp.45-46
• /
• 2007

Lecanora muralis was found on the rock along coastal line during the field trip in Jeju island in 2006. Thallus crustose, placodioid, closely adnate, forming orbicular patches; upper surface grayish green, glossy; central lobes areolate, marginal parts plane, edges thin pruinose; lower surface ecorticate; apothecia sessile, lecanorine type, exciple dense and intact when young, and disc plane, but when mature, exciple laciniate, disc protrudent, yellowish brown to orange, $0.5{\sim}1.5$ mm in diameter; ascospores ellipsoid, simple, colorless, $12.5{\sim}15.0{\times}5.0{\sim}7.5\;{\mu}m$. Usnic acid and zeorin contained in thallus. This is the first record of this species in South Korea.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.25 no.5
• /
• pp.67-72
• /
• 2011

In this study we investigate the background of UPS output transformer(${\Delta}-Y$) operation on neutral ungrounded system, and perform field experiment of neutral floating-phenomenon for the inter-locked securing of electric facilities and improvement of neutral floating-phenomenon. Experiment results show that a floating-phenomenon occurs when four-pole input-breaker trip and the neutral to earth voltage occurring concurrently is identified as phantom voltage. And the measures for the transient overvoltage that can occur in floating-state also are investigated. As a result, the risk elements of neutral ungrounded method as well as neutral floating-phenomenon are removed by installation of separate solidly-grounded transformer and switching four-pole input-breaker to three-pole input breaker.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2009.05a
• /
• pp.263-266
• /
• 2009

IEC 61850 based substation automation system is operating with Generic Object Oriented Substation Event message when an IED need to send an important signal to other IEDs or receive the signals from another IED such as trip and interlock. So interoperability of substation automation system may be assured throughout the verification of IED GOOSE. This paper shows a testing contents for GOOSE subscription and publish of IEC 61850 based IED and describes how to analysis the result of GOOSE testing. Now domestic IED completed by GOOSE test of this study are working in KEPCO test field.

• Proceedings of the KIEE Conference
• /
• 2007.07a
• /
• pp.1605-1606
• /
• 2007

An electrical generator in power plant is driven and maintained its speed at rated by steam turbine. By the way, after synchronization in parallel with the power system, as the steam flow into turbine can not be reduced fast even though the electrical load is lost, the turbine gets into dangerous situation due to the increase of its speed. At this time, the duty of the turbine governor is to limit the speed to its overspeed trip set point by stopping the steam flow as soon as possible, the test of which is called load rejection test. It is introduced in this paper for a field simulation test of generator load rejection to be implemented on the turbine governor in a 680MW nuclear power plant before its startup.

• Journal of The Korean Association For Science Education
• /
• v.27 no.8
• /
• pp.755-764
• /
• 2007

This study examines secondary school science teachers' use of science museums in their teaching and their perception/evaluation/utilization of the educational programs in Korean science museums. We found that teachers do not use science museums in close connection with their formal education; therefore, the students' experiences usually are minimal or are personal experiences. The main reason for this infrequent use of science museums is not because of their insignificant educational effects, but because of the lack of external and administrative support systems. Science teachers want the museums to have structured/organized programs such as science camps or experiments and a lending program which would provide experimental equipment and exhibits relevant to the school science curriculum. 90% of teachers who answered the survey wanted to participate in developing and managing the educational programs of science museums. The educational programs would be used more effectively in relation to formal science learning if the science teachers, who are science education professionals, participated in managing and planning the educational programs of science museums.

• Communications of Mathematical Education
• /
• v.34 no.4
• /
• pp.465-484
• /
• 2020

The purpose of this study was to prove the effect of Mathematics field experience trip program on students' attitude in learning Mathematics. For this we developed Jejumok-Gwanna Math-Tour program in 2019 for students which would make them to walk and experience mathematics in the field. In that program, we suggested several Mathematics examples about natural objects and artifacts in Jejumok-Gwanna. After that, we let A middle school students within Jeju to experience this program in order to see the effect of this program. We asked participants to write pre- and past- questionnaire, have an interview, and write review. After analyzing those, this study concluded that the effect of Jejumok-Gwanna Math-Tour on student's attitude in learning mathematics was statically significant. The result of this study suggested that Mathematics Field Experience Study Program could be useful to improve student's attitude in learning mathematics.

• Journal of Korean Elementary Science Education
• /
• v.36 no.3
• /
• pp.219-226
• /
• 2017

In this study, the reliability and validity of the retrospective pre-post test were analyzed in order to solve the problem of traditional pre-post test including response shift bias. Samples of the study were 162 elementary school students who are studying at the S university gifted education center in Seoul. Before completion of the field trip, we conducted pre test of science-related attitudes. After completion of the field trip, respondents were asked to compare their responses of pre and post science-related attitudes to quantitatively analyze the commonalities and differences of the two tests. To find out more characteristics, qualitative data such as daily records and interview were also gathered and analyzed. The major results of the study are as follows. First, for the paired t-test, there was no statistically significant difference between separate pre-test scores and retrospective pre-test. There was a very high correlation between the separate pre-test scores and the retrospective pre-test. Second, there were significant differences in all seven sub-factors of science-related attitudes between the retrospective pre-test and the post-test. Third, the separate pre-test scores showed a slightly higher tendency than the retrospective pre-test scores. This suggests that the response shift bias appears when it is performed the separate pre-test in affective domain. As a result of the interview, it was found that the evaluation standards of separate pre-test did not match with those of post-test. Forth, internal consistency reliability of the retrospective pre-test was higher than that of the separate pre-test. However, there were significant differences in six factors of science-related attitudes excluding the 'social implications of science' between the separate pre-test and the post-test. Based on these results, the retrospective pre-post test design provides simplicity and convenience to both respondents and investigators, as it is done with one test. The retrospective pre-post test design can be regarded as a valid design for the self-report measurement of affective domain on a single experimental group.

• The Journal of Engineering Geology
• /
• v.26 no.3
• /
• pp.339-352
• /
• 2016

The best way of investigating the physical and mechanical properties of subsurface materials is the combined interpretation of data from borehole geophysical surveys and geotechnical experiments with rock samples. In this study two surface seismic surveys with refraction and surface-wave method are alternatively conducted for downhole seismic surveys in test site for geological field trip in Jeungpyung, Chungbuk. P- and S-wave velocity structures are delineated by refraction and MASW (multichannel analysis of shear waves) methods, respectively. Possion's ratio section, reconstructed from P- and S-wave velocities, is correlated to the outcrop geological features consisting of reddish sedimentary rock, gray volcanic rock, and joints/fractures. In addition, rock samples representative for reddish sedimentary and gray volcanic features are geotechnically analyzed to provide physical, mechanical properties, and elastic modulus. Dynamic elastic moduli estimated from geophysical data is found to be higher than the one from geotechnical data. Reddish sedimentary rock characterized with low porosity and moisture content corresponds to the zone of low electrical resistivities and their small variations in the resistivity sections between the rainy and dry days. This trend suggests that the weathered gray volcanic rock and the nearby fractures with higher low porosity and moisture content are interpreted to be good carrier especially in rainy season.

• Korean Journal of Childcare and Education
• /
• v.3 no.2
• /
• pp.48-67
• /
• 2007

In the case of students hoping to be a nursery school and kindergarten teacher in future, the educational experience which can not learning in the class work was help to increase their understand for the instruction methods in nursery school sport and them to have a instruction mind as a nurser school teacher by direct and concrete. In the aspects, the observation program on an actual spot is a important plan to be a extend of course work and one of alternation programs in child education. This study was emphasized that the observation program is necessary and useful procedure for students who will be prepared a practical training course for 4 weeks and that help to understand the change of their recognition before the observation and after. Also the analytical work was prepared to use usefully for a teacher aspirants to acquire an effective educational method on the actual teaching class. The result shows that the observation program for practical training on an actual sport would give the practical major knowledge to students in course work of a child education school. The educational program which was consisted with the observation and the training course work on the actual sport would be necessary prepared in a regular curriculum for the most of teacher aspirants This systematically analysis explains that the educational program like an observation on actual sport offer to the student as one of course works and it will be sufficiently prepared for promotion of their understand and experience about the child education.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.40 no.6
• /
• pp.98-111
• /
• 2012

This study found the possibility of using cemeteries within the locality as field trip destination. A comparison between Korea and the United States of America's active progress has derived the difference and the implications. Therefore, this article found that the cemetery has sufficient resources based on experience-learning place within the community. Therefore, when the active educational program was developed; it gained more abundant resources for education, as well as provided more different educational opportunities for the students than now. As the result of comparison, the reason why the educational program is actively progressing in the American cemeteries is that a beautiful and fresh environment has been built up such as a park or garden in a cemetery and has been preserved as a healthy forest ecosystem. Furthermore, it is because they actively used the cemetery within a community as the subject. If our cemetery can be renovated and the funeral culture can be changed to break down the image of an avoidable unpleasant facility, it would play a role as a field for learning experience.