• Title/Summary/Keyword: 생 지표도

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Improvement of Short Range Performance of Meteor Burst Path with Buried Antenna (지하 매설형 안테나를 이용한 근거리 유성 버스트 통신의 특성개선)

  • 김병철;김기채;이무영
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.9 no.6
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    • pp.788-801
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    • 1998
  • Meteor Burst Communication can provide effective and economical means of communication where long distance VHF NLOS data transmission is needed ; often ranges more than 1000 km. It has been, however, so far considered unsuitable for short distance application because of phenomenal decrease in burst durations, which leads to decreation of total duty rate of the system. This paper extensively analyzes characteristics of shot distance MB(Meteor Burst) path and shows the low duty rate may be improved by increasing burst rate through adapting antennal beam width to cover entire hot-spot region in the space and, by compensating effective burst length throughcutting down man-made noises introduced by antennal. Based on the analysis, we are developed a small-opening-cavity antennal, especially designed for short distance MB path. In operation, the antenna is to be buried under ground surface so as to improve directivity and reduces noise introduction. The antennal exhibits power gain of 3 dB with 90 degree beam width and thus enables to illuminate entire hot-spot regions with the elevation angle of 8-90 degree which is the case of transmission less than 100 km. Directivity horizontal to earth surface is suppressed to minimum which enables to cut man-made noises from near-by sources down to more than 3 dB from the level reported with conventional 4 element Yagi. A series of experiments performed on 100km MB paths have conformed that, with the antenna installed at receiving site, the burst rate and duration time have been noticed to increase by 10 and 20 percent respectively from the values obtained by conventional 4-element Yagi antennal under same testing condition.

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DEVELOPMENT, GROWTH, AND RELATIONSHIP BETWEEN TEMPERATURE AND METAMORPHOSIS RATE OF THE EARLIER LARVAE ON MACROBRACHIUM ROSENBERGI (DE MAAN) (Macrobrachium rosenbergi (De Maan)의 초기유생의 성장 및 수온과 변태와의 관계)

  • KWON Chin Soo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.7 no.2
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    • pp.52-62
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    • 1974
  • The fresh water prawn, Macrobrachium rosenbergi (De Maan) is a very common species in Info-pacific region inhabiting both fresh and brackish waters in low land areas, and especially abundant in the lower reaches of most rivers which are influenced by seawater, It is one of the largest and commercial species of genus Macrobrachium. As a place of the researches to clear the possibilities of transplantation and propagation of this species in the Far East region the larval development, growth, optimum temperature and metamorphose rate up to first post larvae in aquaruim are cleared under the conditions of salinity $6.58-7.05\%_{\circ}$ Cl, pH 8.0-8.2, the rate of flow 0.3 liter per minute and illumination 3000 lux. Temperature ranged from 27.5 to $28.7^{\circ}C$ during the period of earlier larval development. For the study oil the relationship between temperature and metamorphose rate from zoea to first post larvae, the temperatures in experimental tank were $22.2^{\circ}C\pm1$, $26.1^{\circ}C\pm0.85$, $28.1^{\circ}C\pm0.34$, $30.4^{\circ}C\pm0.66$, $33.7^{\circ}C\pm0.66$, $33.7^{\circ}C\pm0.38$ and $36.8^{\circ}C\pm0.26$. During the work, food used for the larvae was Artemia salina nauplius in the filter-circulation aquariums. This species metamorphosed to the first post-larvae through eleven zoea stages, and the characters of each larval stage are described and optimum temperature for metamorphosis rate and survivals to the first post larvae is $28.1^{\circ}C\pm0.34$.

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Measuring the Professional Development Needs for Technical and Vocational Education and Training Staff in Nepal: A Look at Teachers' Perceptions (네팔 직업기술교육훈련 교사들의 교육훈련 프로그램 요구조사)

  • Lim, Jin Ho;Kim, Dongwook
    • Journal of Practical Engineering Education
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    • v.12 no.1
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    • pp.163-176
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    • 2020
  • Promoting job growth and quality has been central to developing countries to reduce poverty for decades. In this regard, Nepal is not unique in its need to develop effective TVET programme as it is considered showing positive association with workforce development and productivity. While the copious academic literature has highlighted upon staff training programme in general education, it encounters lack of adequate attention in the field of TVET education. The purpose of the study is to identity and prioritise the professional development needs for the teachers of TVET sector in Nepal. A sample(N=317) of Nepalese teachers from seven provinces were asked to answer the scale. The Borich needs assessment model was employed to assess the perceived level of importance and present preferred training modules among 29 teaching subjects. Moreover, a quadrant analysis using 2×2 matrix was used as a diagnostic tool to denote overriding training topics. The result shows that following competence skills constructs were perceived to be in high need of enhancement as well as in existence of discrepancies: 'occupational characteristics of TVET trainer', 'training needs analysis and curriculum development', 'curriculum development based on national competence standard(NCS)', and 'Institution management evaluation'.

The analysis of teaching perspective on good teaching for high school and higher education: pre-service teachers and teachers majored in early childhood education (고등학교와 대학교의 좋은 수업에 대한 관점 분석 -예비유아교사 및 현직교사를 대상으로-)

  • Koh, Eun-hyeon;Park, Hye-Rim
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.12
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    • pp.182-188
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    • 2017
  • This study analyzes several factors of good instruction that have been studied by precedent studies as well as the dominated perspective of teaching that validates the value of good instruction. For this purpose, the authors explore an understanding of the perspective that lessons ought to pursue. The authors examine the difference in the dominated perspective of good instruction of pre-service teacher and teachers through the study methodology of chi-square, one-way analyses of variance, and post-hoc test. The research subjects were enrolled students and graduates of the Department of Early Childhood Education at colleges in Seoul and the Capital area. The TPI that had been objectively indexed with comprehensive understandings and viewpoints of good instruction was also applied. The study result shows that high schools' dominated perspective is "nursing" and colleges' is "apprenticing", regardless of the kind of school. The article discusses the perspective of good instruction by comparing the results of domestic and foreign studies and this study. Some ideas were suggested for further research.

Development and Validation of College Students' Core Competency Assessment: Based on the Case of S University (대학생 핵심역량 진단도구 개발 및 타당화 연구 -S대학 사례를 중심으로-)

  • Kang, Min-Soo;So, Mi-Hyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.4
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    • pp.236-247
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    • 2020
  • This study was conducted with the aim of developing inspection tools to select and measure human resource figures and appropriate core competency of the educational goals pursued by S universities. Therefore, key competency factors were defined consistent with concept of talented figures and educational objectives of S universities, inspection tools were developed to measure core competences, and directions are presented for future education policies and curriculum compilation and securing data for rational operation. Based on key competency indicators, questions were developed in a self-reporting form that measures the consent level of the respondents by comprising seven areas of competence, 16 small areas (sub-capacity), and 46 questions. The main Test conducted an analysis of the questionnaires based on the survey results of 2,486 people to ensure the validity of the inspection by conducting a positive factor analysis and reliability analysis. The core competency diagnostic tool of S university is meaningful in this study which verifies the effectiveness of the curriculum and programs conducted at S university and as the first step for the rational operation of the core competency certification system to improve the competency appropriate for students.

The Evaluation of Application to MODIS LAI (Leaf Area Index) Product (MODIS LAI (엽면적지수) Product의 활용성 평가)

  • Ha, Rim;Shin, Hyung-Jin;Park, Geun-Ae;Hong, Woo-Yong;Kim, Seong-Jun
    • Journal of the Korean Association of Geographic Information Studies
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    • v.11 no.2
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    • pp.61-72
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    • 2008
  • Leaf area index (LAI) is a key biophysical variable influencing land surface processes such as photosynthesis, transpiration and energy balance, and is a required input to estimate evapotranspiration in various ecological and hydrological models. The development of more correct and useful LAIs estimation techniques is required by these importance, but LAIs had been assumed in most LAI research through simple relations with the normalized difference vegetation index (NDVI) because the field measurement is difficult on wide area. This paper is to evaluate the MODIS LAI Product's practical use by comparing with LAIs that is derived from NOAA AVHRR NDVIs and the 2 years (2003-2004) measured LAIs of Korea Forest Research Institute in Gyeongancheon watershed (561.12 $Km^2$). As a result, the MODIS LAIs of deciduous forests showed higher values about 14 % and 15~30 % than the measured LAIs and NOAA LAIs. In the year of 2003, the MODIS LAIs in coniferous forests were 5 % higher than the measured LAIs, and showed about 7 % differences comparing with the NOAA LAIs except April. These differences come from the insufficient field data measured in partial points of the target area, and the extracted reference data from MODIS LAIs include the limits of spatial resolution and the error of incorrect land cover classification. Thus, using the MODIS data by the proper correction with the measured data can be useful as an input data for ecological and hydrological models which offers the vegetation information and simulates the water balance of a given watershed.

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The Flora and Vegetation of the Dongjin River (동진강의 식물상과 식생)

  • Lee, Kyeong-Bo;Kim, Chang-Hwan;Lee, Deog-Bae;Kim, Jong-Gu;Park, Chan-Won
    • Korean Journal of Environmental Agriculture
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    • v.23 no.1
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    • pp.34-40
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    • 2004
  • This study was conducted to get some vegetation information and to find out a way to conseue the ecosystem in the Dongjin River. The riparian vegetation was investigated by Zurich-Montpellier school's method from June 2001 to March 2002. The number of riparian plants were 73 families, 188 genera, 238 species, 33 varieties or 272 Taxa in Dongjin River. The characteristics of life farm spectra were 97 therophytes (35.7%), 78 hydrophytes (28.7%), 41 hemicryptophytes (15.1%) 22 geophytes (8.1%), and 12 chamaephytes (4.4%). The riparian vegetation was identified 8 plant communities (Potamogeton brechtoldii, Hydrilla verticillata, Ceratophyllum demersum, Potamogeton malaianus, Phragmites japonica, Persicaria thunbergii, Cardamine scutata, Persicaria hydropiper) in upstream, 4 plant communities (Zizania latifoliar, Phragmites communis, Persicaria thunbergii, Humulus japonicus) in midstream and 8 plant communities (Hydrocharis dubia, Ceratophyllum demersum, Trapa japonica, Zizania latifolia, Paspalum distichum, Phragmites communis, Pericaria thunbergii, Amphicarpaea edgeworthii) in downstream of the Dongjin River.

Autotrophic Perchlorate-Removal Using Zero-Valent Iron and Activated Sludge: Batch Test (영가철과 활성슬러지를 이용한 독립영양방식의 퍼클로레이트 제거: 회분배양연구)

  • Ahn, Yeong-Hee;Ha, Myoung-Gyu
    • Journal of Life Science
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    • v.21 no.3
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    • pp.444-450
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    • 2011
  • Perchlorate ($ClO_4^-$) is a contaminant found in surface water and soil/ground water. Autotrophic perchlorate-reducing bacteria (PRB) use hydrogen gas ($H_2$) as an electron donor to remove perchlorate. Since iron corrosion can produce $H_2$, feasibility of autotrophic perchlorate-removal using zero-valent iron (ZVI) was examined in this study using activated sludge that is easily available from a wastewater treatment plant. Batch test showed that activated sludge microorganisms could successfully degrade perchlorate in the presence of ZVI. The perchlorate biodegradation was confirmed by molar yield of $Cl^-$ as perchlorate was degraded. Scanning electron microscope revealed that rod-shaped microorganisms on the surface of iron particles used for the autotrophic perchlorate-removal, suggesting that iron particles could serve as supporting media for the formation of biofilm as well. DGGE analyses revealed that microbial profile of the inoculum (activated sludge) was different from that of biofilm sample obtained from the ZVI-added enrichment culture used for $ClO_4^-$-degradation. A major band of the biofilm sample was most closely related to the class Clostridia.

A Study on the Customized Services of University Libraries According to MBTI Personality Types of College Students (대학생의 MBTI 성격유형에 따른 대학도서관 맞춤형 서비스에 관한 연구)

  • Kwak, Woojung;Noh, Younghee;Ahn, Inja;Zhang, Jingjing
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.30 no.4
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    • pp.91-114
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    • 2019
  • This study intends to classify the users by the MBTI personality type and investigate and analyze information resources and services of library preferred by personality type. Towards this end, we have surveyed the K University students on their personality types and preferred resources and services, and also attempted to explore the possibility of providing customized information services of university libraries according to the MBTI personality type based on the results. As a result of the study, it turned out that there was a significant difference in the preference of digital contents type in the analysis of the data type preference and the quadrant type through the analysis of attitude index type from validating the difference between data / information source and service preference according to the MBTI type. The analysis of 16 types of personality also demonstrated a significant difference in the perception of digital contents. Accordingly, In order to provide services for data and digital contents suitable for personality types in university libraries, it should be preceded by collecting MBTI personality type data for users in the library. After that, when a user requests a reference information service from a library, or requests a book or information, it is necessary to provide a form-specific service or provide a content-specific service.

Difference of Facial Skin Temperature Responses between Fear and Joy (공포와 기쁨 정서 간 안면온도 반응의 차이)

  • Eum, Yeong-Ji;Eom, Jin-Sup;Sohn, Jin-Hun
    • Science of Emotion and Sensibility
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    • v.15 no.1
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    • pp.1-8
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    • 2012
  • There have been many emotion researches to investigate physiological responses on specific emotions with physiological parameters such as heart rate, blood volume flow, and skin conductance. Very few researches, however, exists by detecting them with facial skin temperature. The purpose of present study was to observe the differences of facial skin temperature by using thermal camera, when participants stimulated by monitor scenes which could evoke fear or joy. There were totally 98 of participants; undergraduate students who were in their adult age and middle, high school students who were in their adolescence. We measured their facial temperature, before and after presenting emotional stimulus to see changes between both times. Temperature values were extracted in these regions; forehead, inner corners of the eyes, bridge of the nose, end of the nose, and cheeks. Temperature values in bridge and end of the nose were significantly decreased in fear emotion stimulated. There was also significant temperature increase in the area of forehead and the inner corners of the eyes, while the temperature value in end of the nose decreased. It showed decrease in both stimulated fear and joy. These results might be described as follows: When arousal level going up, sympathetic nervous activity increases, and in turn it makes blood flow in peripheral vessels under the nose decrease. Facial temperature changes by fear or joy in this study were the same as the previous studies which measured temperature of finger tip, when participants experiencing emotions. Our results may help to develop emotion-measuring techniques and establish computer system bases which are to detect human emotions.

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