Students’ Perspectives on Pre-recorded Video Lectures Versus Video-Conferencing Lectures in the Untact Era

Kim,Hea-Suk,Cha,Yoonjung,Kim,Na-Young 이화여자대학교 교과교육연구소 2021 교과교육학연구 Vol.25 No.2

The purpose of this study is to examine students’ perspectives on two online learning formats: pre-recorded video lectures versus video-conferencing. There were 90 participants who took College English courses in a university in Seoul. Participants took TOEIC tests before taking the classes and were divided into two different proficiency level groups: a high-level group and a low-level group. All participants studied English via both pre-recorded video lectures and video-conferencing (Zoom) for the whole semester. Questionnaires were carried out to explore students’ perspectives on both online formats in accordance with their proficiency levels. The findings of the closed-ended questionnaires revealed that significant differences were not found between the low- and high-level groups regardless of the online learning formats. Regarding students’ perspectives about these online English formats, a statistical difference was not found between the two groups. It is worth noting that students did not show any significantly different perspectives concerning online courses regardless of their proficiency levels. As for the open-ended questionnaires, both groups noted various benefits and drawbacks of the current online learning platforms. Also, they provided constructive suggestions for these online learning formats. The results of this study have pedagogical implications for carrying out successful online courses.

효모 세포벽 분해효소 생산균의 탐색 및 효소생산 최적조건의 조사

차성관,최혜숙,김왕준,윤석후,김영배 한국미생물생명공학회 ( 구 한국산업미생물학회 ) 1996 한국미생물·생명공학회지 Vol.24 No.2

담자효모 세포벽을 분해하는 효소 생산균의 탐색을 위하여 50여 토양시료와 방선균 1000여개의 미생물을 가지고 3차에 걸친 탐색작업을 실시한 결과 1차적으로 autolysed washed yeast 배지 위에서 투명한 생성크기로 493개 균주를 선발하였으며, 이 균주들을 2차적으로 생효모 한천배지 위에서의 투명한 생성 크기로 117개 균주를 선발 하였다. 선발된 균주들을 가지고 용해활성도의 측정방법을 이용하여 최종적으로 St-1702 균주가 선발되었고, St-1702 균주는 동정 실험결과 잠정적으로 Streptomyces eurythermus 또는 그 유연균으로 동정되어졌다. St-1702 균주를 이용하여 효소생산 최적조건을 조사한 결과 최적배지 및 배양조건은 다음과 같았다 : freeze dried yeast 2% glucose 1%, K_2HPO_4 1%, MgSO_4·7H_2O, 1% peptone 0.5% (NH_4)_2CO_3 0.2% 초기 pH 값 7.0의 배지 및 30℃에서 3일간 배양. 최적배지에서 선발균주를 배양한 배양액을 이용하여 담자효모들의 원형질체 형성 실험을 한 결과 시중에서 구입된 효모 세포벽 분해 효소들보다 더 높은 원형질체 형성률을 보여 주었다. Thousand actinomycetes and 50 soil samples were used for the isolation of microorganisms producing yeast cell wall lytic enzymes. Among 493 strains producing large clear zones on autolysed washed yeast (AWY), 117 strains were selected on living yeast cell agar plates. With the method of lytic activity, one strain (St-1702) was selected, which was temporarily identified as Streptomyces eurythermus. The optimal condition for enzyme production of this strain was partially determined as follows: incubation of the strain for 3 days at 30℃ in the medium containing 2% freeze dried yeast cell, 1% glucose, 1% K_2HPO_4, 0.01% MgSO_4·^7H_2O, 0.5% peptone, and 0.2% (NH_4)_2CO_3 with pH 7.0. The protoplast formation of yeast by using the enzyme produced by this strain was compared with commercial enzymes.

남자 고등학교 세팍타크로 경기의 공격기술에 관한 분석 연구

김영호,고문석,제임스전,이영익,차정훈,현종건,김범수,임종만,이석인 한국스포츠리서치 2004 한국 스포츠 리서치 Vol.15 No.6

This research aims at analysis of attack technique in sepaktakraw games. For this purpose, 3 high school coaches observed and recorded each game Five times in videos of high school male players' thirty games in 2003. The conclusion from the analysis of the recorded data are as follows. 1. Scissors spike was the most popular (favorite) attack technique. Rolling spike, tapping spike and heading spike was popular in order. 2. Heading spike showed the highest success rate (73.5%) in attack technique. And tapping spike (69.5%), scissors spike (57.8%) and rolling spike (67.11) showed a lower success rate in order. In failure rate, heading spike (5.5%), tapping spike (36.5%), scissors spike (32.2%) and rolling spike (32.9%) had a higher percentage in order. 3. When receive was stable, the success rate in attach technique was 47.1%, the failure rate was 20.1%. On the other hand, when receive was unstable, the success rate in attach technique was 16.5%, the failure rate was 14.3%.

직장 네티즌들의 인터넷 여행사 이용실태에 관한 연구

차석빈,김종문,우경식 한국문화관광학회 2000 문화관광연구 Vol.2 No.1

The development of internet environment in the society caused the travel industry to proceed into the internet business competitively. However, a little research has been conducted on the netizens' behavior in the internet travel businesses. This study attempted to address the behavioral aspects related to the internet use for salaried men visiting internet travel agencies(ITA). Research findings are as follows: 1)Netizens seemed not to invest much time in searching travel-related sites. Major purposes of their visiting ITA were acquiring travel information, hotel/condominium reservation, package product reservation, etc. 2) They thought the provision of travel information, protection of private information, and internet connecting speed important in purchasing travel product through internet. 3) They revealed high intention to visit ITA, but low to purchase goods. However, netizens who had experience of purchasing goods show higher intention to visit or purchase than those who did not visit ITA even one time.

활성화된 석탄회분 칼럼을 이용한 염료의 흡착특성

김선숙,이승열,김차영,이철희 嶺南大學校 環境問題硏究所 1995 環境硏究 Vol.14 No.2

유연탄의 연소시에 발생되는 산업폐기물인 coal ash를 산처리하여 activated coal ash로 개량하여 흡착제로 사용하고 반응성 염료인 Sumifix Red와 산성염료인 Red EB-L을 시료수로 사용하여 흡착실험을 한 결과 pH에 따른 흡착제거율은 시료수 모두 pH 3~9범위에서는 거의 변동이 없었으나, pH 11에서는 급격하게 감소하였고, 반응시간에 따른 흡착제거율은 activated coal ash를 10g 주입했을 경우 0.5시간 경과후에 Sumifix Red는 54.8%, Red EB-L은 88.7%로 나타났으며, 5시간 경과 후엔 변화가 거의 없었고, 온도에 따른 흡착제거율은 Red EB-L에 있어서는 거의 변동이 없었고, Sumifix Red에서는 15℃에서 가장 높았고 온도가 증가함에 따라 제거율은 감소하는 경향을 나타내었다. 또한, Freundlich 흡착등온식을 이용하여 흡착이 평형에 도달했을 때의 평형농도와 흡착량과의 관계에서 1/n과 k값은 반응성 염료인 Sumifix Red가 각각 0.604, 0.016이었고, 산성 연료인 Red EB-L은 0.921, 0.058로 나타났다. 칼럼을 이용한 activated coal ash의 흡착제거율을 살펴본 결과는 회분식에서와 마찬가지로 Red EB-L이 Sumifix Red보다 높았고, Bohart와 Adams의 식을 이용하여 흡착칼럼을 설계 해 본 결과 흡착용량은 Red EB-L이 74.96kg/m³,17.22kg/m³ 이었으며, activated coal ash이 이론적 충진깊이는 Red EB-L과 Sumifix Red 모두 0.1m 정도로 나타났다. This study was conducted to investigate the characteristics of absorption in continuous waste water treatment system containing activated coal ash. Activated coal ash was produced from bituminous coal and treated by direct acid leaching(DAL) in order to get better activity as porosity absorbent. On this experiment performed by batch and continuous methods, acid and reactive type dyes were selected to find out the feasibility of activated coal ash as absorbent. The absorption removal rate of activated coal ash were nearly constant at the pH range of 3 to 9 on Red EB-L and Sumifix Red. But reduced rapidly at pH 11. The adsorption removal rate of absorbent was not changed at the temperature range of 15℃ ~ 45℃ on acid dye Red EB-L. But in case of reactive dye Sumifix Red, absorption removal rate was reduced at 15℃. When the absorption equilibrium was calculated based on the Freundlich isotherm equation, constant k was 0.016, 0.058 and 1/n was 0.604, 0.921 for Sumifix Red, Red EB-L, respectivey. Removal rate of acid dye Red EB-L was higher than that of reactive dye Sumifix Red by activated coal ash at the continuous column system. Batch system illustrated same tendency. The absorption capacities of absorption column, designed by Bohart and Adams equation, were 74.96 kg.m³17.22 kg/m³ for Red EB-L, Sumifix Red, respectively, and theoretical packing depth of activated coal ash was 0.1 m for all.

KOH를 함침시킨 활성탄 흡착제의 H₂S 흡착특성

차선영,이석기,김한수,박영성 大田大學校 環境問題硏究所 1999 환경문제연구소 논문집 Vol.4 No.-

H2S adsorption characteristics of the impregnated activated carbon adsorbent were investigated. KOH reagent was used for impregnating the activated carbon. For analyses of the impregnated activated carbon adsorbent, various methods such as TGA test and acid-base titration, as well as measurements of BET surface and pH were adopted. As operating variables, adsorption temperature (25~45℃) and H₂S concentration(4.96~18.23mg/ℓ) were applied. The experimental results showed that the H₂S adsorption equilibrium capacity of KOH impregnated activated carbon adsorbent increased with increasing temperature and H₂S concentration.

Exploring the Use of a Machine Translator on EFL Learners’ Reading Comprehension

Kim,Hea-Suk,Cha Yoonjung 영상영어교육학회 2020 영상영어교육 (STEM journal) Vol.21 No.1

The study aims to examine whether a machine translator can be effective in promoting learners’ performance in reading comprehension. The main reason for using a machine translator, in this case Papago, was to increase students’ engagement in order to better comprehend the content of selected reading materials. Twenty-seven students were assigned to a wordlist group while thirty-four were assigned to a Papago group. The wordlist group was provided with a wordlist before reading the main texts while the Papago group used Papago. Both groups took a reading comprehension test before and after the experiment. The test comprised 20 reading comprehension and vocabulary questions. A significant difference in reading performance was found between the wordlist group and the Papago group. Furthermore, the results of the survey revealed that the participants’ perspectives in both groups showed significant differences in all items. Open-ended responses demonstrated the benefits and drawbacks of utilizing the wordlists and Papago. Consequently, the findings of this study indicate that students preferred the wordlists to Papago for understanding the reading texts. That is, using machine translators may not be useful in L2 reading. In this light, several pedagogical implications for designing and using machine translators are proposed.

XSL-FO 문서에 대한 PostScript 변환기 설계

유동석,김차종 한밭대학교 정보통신전문대학원 2004 정보통신전문대학원 논문집 Vol.2 No.1

현재의 전자문서처리 환경은 WYSiWYG방식이다. 이를 위해 문서를 논리적인 구조와 물리적인 구조로 구조화하였고 이러한 구조를 마크업언어로 표현하고 있다. 특히 인터넷상의 전자문서 작성 및 교환을 위한 마크 업언어로 XML이 발표되어 전자문서의 표현과 같은 전통적인 사용에서부터 검색을 위한 데이터베이스화에 이르기까지 전자문서의 활용 영역이 다양해지고 있다. 그러나 출력 품질 면에서 워드프로세서나 전자출판에 의한 전 자문서와 XML. 문서의 출력 품질은 매우 큰 차이가 있다. 이는 비록 XML문서가 스타일 정보를 포함하고 있긴 하지만 화면 출력과 인쇄 매체로의 출력 모두 고품질의 출력을 위한 적용이 부족했기 때문이다. 이러한 문제 해결 을 위해 W3C에서는 고품질의 XML출력 문서를 얻을 수 있도록 XSL-FO(XSL-Formatting Object)를 개발 하였다. 한편 고품질의 전자출판물을 얻기 위해 페이지 기술 언어(PDL)가 필요하고, 이의 업계표준인 PostScript가 이미 널리 사용되고 있다. 따라서 본 논문에서는 XML-FO를 Postscript에 적용함으로써 고품질의 XML 출력문서를 얻기 위한 변환기를 설계하였다. At present, the electronic document is being processed in WYSWYG mode. For this, a document is structured by the logical structure and the physical structure, and is presented by the markup language. After XML is announced, and application scope of the electronic document is extended from interchanging to searching. However, in point of output quality, a XML document image on a browser has lower quality than a general document image on desktop publishing. The reason is which output function of a browser has not capability for high quality printing. The W3C developed XSL-FO(XSL-formatting Object) for stylesheet formatting and PDL(Page Sescription Language) as like PostScript is already developed and used widely. In this paper, we designed the PostScript-Converter to get a high quality document image by converting XSL-FO into PostScript format.

다채널 광정렬 장치에서의 다자유도 회전 스테이지 동작 특성에 관한 연구

정상화,차경래,김현욱,최석봉,김광호,박준호 한국공작기계학회 2005 한국공작기계학회 춘계학술대회논문집 Vol.2005 No.-

In recent years, as the demands of VBNS(Very high speed Backbone Network Service) and VDSL(Very high-data rate Digital Subscriber Line) increase, the development of kernel parts of optical communication such as PLC(Planar Light Circuit), Coupler, WDM elements increase. The alignment and the attachment technology are very important to fabricate the optical elements for communication. In this paper, the mechanism of rotational stage are studied. with the three different method and the results of them are applied to the design of the system. The performance test of resolution and travel is performed.

초정밀 광소자 정렬 스테이지의 구동 특성에 관한 연구

정상화,차경래,김현욱,최석봉,김광호,박준호 한국공작기계학회 2005 한국공작기계학회 춘계학술대회논문집 Vol.2005 No.-

As the optical communication is introduced to the backbone network at first and becomes a general communication method of network, the demand of kernel parts of optical communication such as PLC(Planar Light Circuit), Coupler, and WDM(Wavelength Division Multiplexing) element increases. The alignment and the attachment technology are very important in the fabrication of optical elements. In this paper, the driving mechanism of ultra precision stage is studied with the aim of optimal design of stage. The travel and the resolution of stage are investigated. The hysteresis of the stage is generated because of PZT actuator. The hysteresis and the inverse hysteresis are modeled in X, Y, and Z-axis motion. The input data of desired displacement to the stage according to input voltage is obtained from the inverse hysteresis equation. In the result of experiments with the input data, the errors due to hysteresis are well compensated.