• 제목/요약/키워드: Utility power system

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Why A Multimedia Approach to English Education\ulcorner

  • Keem, Sung-uk
    • 대한음성학회:학술대회논문집
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    • 대한음성학회 1997년도 7월 학술대회지
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    • pp.176-178
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    • 1997
  • To make a long story short I made up my mind to experiment with a multimedia approach to my classroom presentations two years ago because my ways of giving instructions bored the pants off me as well as my students. My favorite ways used to be sometimes referred to as classical or traditional ones, heavily dependent on the three elements: teacher's mouth, books, and chalk. Some call it the 'MBC method'. To top it off, I tried audio-visuals such as tape recorders, cassette players, VTR, pictures, and you name it, that could help improve my teaching method. And yet I have been unhappy about the results by a trial and error approach. I was determined to look for a better way that would ensure my satisfaction in the first place. What really turned me on was a multimedia CD ROM title, ELLIS (English Language Learning Instructional Systems) developed by Dr. Frank Otto. This is an integrated system of learning English based on advanced computer technology. Inspired by the utility and potential of such a multimedia system for regular classroom or lab instructions, I designed a simple but practical multimedia language learning laboratory in 1994 for the first time in Korea(perhaps for the first time in the world). It was high time that the conventional type of language laboratory(audio-passive) at Hahnnam be replaced because of wear and tear. Prior to this development, in 1991, I put a first CALL(Computer Assisted Language Learning) laboratory equipped with 35 personal computers(286), where students were encouraged to practise English typing, word processing and study English grammar, English vocabulary, and English composition. The first multimedia language learning laboratory was composed of 1) a multimedia personal computer(486DX2 then, now 586), 2) VGA multipliers that enable simultaneous viewing of the screen at control of the instructor, 3) an amplifIer, 4) loud speakers, 5)student monitors, 6) student tables to seat three students(a monitor for two students is more realistic, though), 7) student chairs, 8) an instructor table, and 9) cables. It was augmented later with an Internet hookup. The beauty of this type of multimedia language learning laboratory is the economy of furnishing and maintaining it. There is no need of darkening the facilities, which is a must when an LCD/beam projector is preferred in the laboratory. It is headset free, which proved to make students exasperated when worn more than- twenty minutes. In the previous semester I taught three different subjects: Freshman English Lab, English Phonetics, and Listening Comprehension Intermediate. I used CD ROM titles like ELLIS, Master Pronunciation, English Tripple Play Plus, English Arcade, Living Books, Q-Steps, English Discoveries, Compton's Encyclopedia. On the other hand, I managed to put all teaching materials into PowerPoint, where letters, photo, graphic, animation, audio, and video files are orderly stored in terms of slides. It takes time for me to prepare my teaching materials via PowerPoint, but it is a wonderful tool for the sake of presentations. And it is worth trying as long as I can entertain my students in such a way. Once everything is put into the computer, I feel relaxed and a bit excited watching my students enjoy my presentations. It appears to be great fun for students because they have never experienced this type of instruction. This is how I freed myself from having to manipulate a cassette tape player, VTR, and write on the board. The student monitors in front of them seem to help them concentrate on what they see, combined with what they hear. All I have to do is to simply click a mouse to give presentations and explanations, when necessary. I use a remote mouse, which prevents me from sitting at the instructor table. Instead, I can walk around in the room and enjoy freer interactions with students. Using this instrument, I can also have my students participate in the presentation. In particular, I invite my students to manipulate the computer using the remote mouse from the student's seat not from the instructor's seat. Every student appears to be fascinated with my multimedia approach to English teaching because of its unique nature as a new teaching tool as we face the 21st century. They all agree that the multimedia way is an interesting and fascinating way of learning to satisfy their needs. Above all, it helps lighten their drudgery in the classroom. They feel other subjects taught by other teachers should be treated in the same fashion. A multimedia approach to education is impossible without the advent of hi-tech computers, of which multi functions are integrated into a unified system, i.e., a personal computer. If you have computer-phobia, make quick friends with it; the sooner, the better. It can be a wonderful assistant to you. It is the Internet that I pay close attention to in conjunction with the multimedia approach to English education. Via e-mail system, I encourage my students to write to me in English. I encourage them to enjoy chatting with people all over the world. I also encourage them to visit the sites where they offer study courses in English conversation, vocabulary, idiomatic expressions, reading, and writing. I help them search any subject they want to via World Wide Web. Some day in the near future it will be the hub of learning for everybody. It will eventually free students from books, teachers, libraries, classrooms, and boredom. I will keep exploring better ways to give satisfying instructions to my students who deserve my entertainment.

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암모니아 액화 시나리오에 따른 그린암모니아 합성 공정의 경제성 및 환경 영향도 평가 (Techno-economic Analysis and Environmental Impact Assessment of a Green Ammonia Synthesis Process Under Various Ammonia Liquefaction Scenarios)

  • 김건영;송인서;구보람;박기호
    • Korean Chemical Engineering Research
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    • 제62권2호
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    • pp.163-172
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    • 2024
  • 본 연구에서는 이산화탄소를 배출하지 않고 수소를 운반할 수 있는 그린 암모니아 공정의 효율적인 설계를 위해 암모니아 액화 시나리오를 다르게 설계하고 이에 대한 경제성 및 환경 영향도 평가를 수행하였다. 순도 99.9 mol%의 148 kmol/hr 액화 암모니아를 생산물로 얻는 것을 목표로 설정하였고 후처리 단계에서 냉각단계 전 기-액분리를 통해 일정량의 액화 암모니아를 분리하고 고압에서 냉각하는 고압 냉각 공정과 기-액분리 과정 없이 바로 감압 후 냉각하여 기-액분리를 시켜 최종생산물을 얻는 저압 냉각 공정의 두 가지 케이스를 설정했다. 이에 대한 타당성 평가를 위해 Aspen Plus를 활용한 시뮬레이션을 수행하였다. 고압 냉각 공정은 많은 기-액분리 공정과 열교환기를 사용하여 초기장치 비용이 부담되지만 상대적으로 총 유틸리티 비용이 91.03 $/hr, duty가 2.81 Gcal/hr 낮아 유지비용이 적게 든다. 저압 냉각 공정은 초기 장치 비용이 낮고 운전이 용이하지만 급격한 압력 강하로 운전이 불안정한 것을 확인 하였다. 환경 영향도 평가 결과 고압 냉각 공정이 저압 냉각 공정보다 전력 사용량을 기준으로 산출한 이산화탄소 환산톤 배출 계수가 0.83 tCO2eq 더 낮아 환경친화적 임을 확인할 수 있었다. 본 연구 결과를 통해 향후 그린 암모니아 합성 공정에서 여러 상황에 적절한 설계안을 도출할 수 있는 데이터베이스를 확보할 수 있다.

서비스제공자와 사용자의 인식차이 분석을 통한 소셜커머스 핵심성공요인에 대한 연구: 한국의 티켓몬스터 중심으로 (A Study on the Critical Success Factors of Social Commerce through the Analysis of the Perception Gap between the Service Providers and the Users: Focused on Ticket Monster in Korea)

  • 김일중;이대철;임규건
    • Asia pacific journal of information systems
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    • 제24권2호
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    • pp.211-232
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    • 2014
  • Recently, there is a growing interest toward social commerce using SNS(Social Networking Service), and the size of its market is also expanding due to popularization of smart phones, tablet PCs and other smart devices. Accordingly, various studies have been attempted but it is shown that most of the previous studies have been conducted from perspectives of the users. The purpose of this study is to derive user-centered CSF(Critical Success Factor) of social commerce from the previous studies and analyze the CSF perception gap between social commerce service providers and users. The CSF perception gap between two groups shows that there is a difference between ideal images the service providers hope for and the actual image the service users have on social commerce companies. This study provides effective improvement directions for social commerce companies by presenting current business problems and its solution plans. For this, This study selected Korea's representative social commerce business Ticket Monster, which is dominant in sales and staff size together with its excellent funding power through M&A by stock exchange with the US social commerce business Living Social with Amazon.com as a shareholder in August, 2011, as a target group of social commerce service provider. we have gathered questionnaires from both service providers and the users from October 22, 2012 until October 31, 2012 to conduct an empirical analysis. We surveyed 160 service providers of Ticket Monster We also surveyed 160 social commerce users who have experienced in using Ticket Monster service. Out of 320 surveys, 20 questionaries which were unfit or undependable were discarded. Consequently the remaining 300(service provider 150, user 150)were used for this empirical study. The statistics were analyzed using SPSS 12.0. Implications of the empirical analysis result of this study are as follows: First of all, There are order differences in the importance of social commerce CSF between two groups. While service providers regard Price Economic as the most important CSF influencing purchasing intention, the users regard 'Trust' as the most important CSF influencing purchasing intention. This means that the service providers have to utilize the unique strong point of social commerce which make the customers be trusted rathe than just focusing on selling product at a discounted price. It means that service Providers need to enhance effective communication skills by using SNS and play a vital role as a trusted adviser who provides curation services and explains the value of products through information filtering. Also, they need to pay attention to preventing consumer damages from deceptive and false advertising. service providers have to create the detailed reward system in case of a consumer damages caused by above problems. It can make strong ties with customers. Second, both service providers and users tend to consider that social commerce CSF influencing purchasing intention are Price Economic, Utility, Trust, and Word of Mouth Effect. Accordingly, it can be learned that users are expecting the benefit from the aspect of prices and economy when using social commerce, and service providers should be able to suggest the individualized discount benefit through diverse methods using social network service. Looking into it from the aspect of usefulness, service providers are required to get users to be cognizant of time-saving, efficiency, and convenience when they are using social commerce. Therefore, it is necessary to increase the usefulness of social commerce through the introduction of a new management strategy, such as intensification of search engine of the Website, facilitation in payment through shopping basket, and package distribution. Trust, as mentioned before, is the most important variable in consumers' mind, so it should definitely be managed for sustainable management. If the trust in social commerce should fall due to consumers' damage case due to false and puffery advertising forgeries, it could have a negative influence on the image of the social commerce industry in general. Instead of advertising with famous celebrities and using a bombastic amount of money on marketing expenses, the social commerce industry should be able to use the word of mouth effect between users by making use of the social network service, the major marketing method of initial social commerce. The word of mouth effect occurring from consumers' spontaneous self-marketer's duty performance can bring not only reduction effect in advertising cost to a service provider but it can also prepare the basis of discounted price suggestion to consumers; in this context, the word of mouth effect should be managed as the CSF of social commerce. Third, Trade safety was not derived as one of the CSF. Recently, with e-commerce like social commerce and Internet shopping increasing in a variety of methods, the importance of trade safety on the Internet also increases, but in this study result, trade safety wasn't evaluated as CSF of social commerce by both groups. This study judges that it's because both service provider groups and user group are perceiving that there is a reliable PG(Payment Gateway) which acts for e-payment of Internet transaction. Accordingly, it is understood that both two groups feel that social commerce can have a corporate identity by website and differentiation in products and services in sales, but don't feel a big difference by business in case of e-payment system. In other words, trade safety should be perceived as natural, basic universal service. Fourth, it's necessary that service providers should intensify the communication with users by making use of social network service which is the major marketing method of social commerce and should be able to use the word of mouth effect between users. The word of mouth effect occurring from consumers' spontaneous self- marketer's duty performance can bring not only reduction effect in advertising cost to a service provider but it can also prepare the basis of discounted price suggestion to consumers. in this context, it is judged that the word of mouth effect should be managed as CSF of social commerce. In this paper, the characteristics of social commerce are limited as five independent variables, however, if an additional study is proceeded with more various independent variables, more in-depth study results will be derived. In addition, this research targets social commerce service providers and the users, however, in the consideration of the fact that social commerce is a two-sided market, drawing CSF through an analysis of perception gap between social commerce service providers and its advertisement clients would be worth to be dealt with in a follow-up study.

위성 자료를 이용한 도시지역 극치강우 모니터링: 2011년 7월 집중호우를 중심으로 (Validation of Extreme Rainfall Estimation in an Urban Area derived from Satellite Data : A Case Study on the Heavy Rainfall Event in July, 2011)

  • 윤선권;박경원;김종필;정일원
    • 한국수자원학회논문집
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    • 제47권4호
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    • pp.371-384
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    • 2014
  • 본 논문에서는 천리안(Communication, Ocean and Meteorological Satellite; COMS)과 TRMM(Tropical Rainfall Measurement Mission)을 통하여 관측한 위성영상자료를 이용한 극치강우(Extreme Rainfall) 추정 알고리즘을 개발하였으며, 2011년 7월 집중호우를 대상으로 그 적용성을 평가하였다. TRMM/PR(TRMM/Precipitation Radar)과 AWS(Automatic Weather System) 자료를 이용하여 고도에 따른 멱급수 회귀방정식으로 Z-R관계식을 추정한 결과 $Z=303R^{0.72}$를 산출하였으며, 지상관측 자료와 비교한 결과 상관계수가 0.57로 분석되었다. 이 값과 TRMM/VIRS(TRMM/Visible Infrared Scanner)와의 관계를 이용하여 극치강우알고리즘을 개발하였으며, 천리안 위성에 적용하여 10분강 우를 추정한 결과 강우강도가 큰 경우에는 과소 추정하는 경향이, 작은 경우에는 과대 추정하는 경향이 있는 것으로 분석되었으나, 전반적인 패턴은 관측과 유사한 경향이 있는 것으로 분석되었다. 또한 이 알고리즘을 같은 센서를 이용하는 천리안 위성에 적용하여 AWS의 상관관계를 분석한 결과, 10분 강우량의 경우 상관계수는 0.517로 평균제곱근 오차는 3.146으로 분석되었고, 공간 상관행렬 오차의 평균은 -0.530~-0.228의 음의 상관을 보이는 것으로 분석되었다. 위성자료를 이용한 극치강우량 추정의 오차 발생 원인은 여러 가지 외부적인 요인으로 판단되며, 지속적인 알고리즘 개선 및 오차보정을 통한 정확도 개선이 필요한 것으로 사료된다. 본 연구의 결과는 추후 다양한 정지궤도위성의 이용을통 한 다중 원격탐사자료의 활용으로 보다 정확한 미계측 유역 수문자료 확충 및 실시간 홍수 예 경보 시스템 구축에 활용이 가능할 것으로 사료된다.

한국형 코즈믹 레이 토양수분 관측 시스템을 위한 국내 적용성 연구 (A Study on Domestic Applicability for the Korean Cosmic-Ray Soil Moisture Observing System)

  • 정재환;조성근;이슬찬;김기영;이용준;이충대;이신재;최민하
    • 대한원격탐사학회지
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    • 제39권2호
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    • pp.233-246
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    • 2023
  • 수문순환의 이해와 효율적 수자원 관리의 측면에서 토양수분의 중요성이 조명되고 있으나, 국내에는 양질의 지점 토양수분 자료의 부재로 그 활용도가 매우 낮은 실정이다. 때문에 인공위성 기반의 토양수분을 적용할 때에도, 기준자료가 되는 지상 관측자료가 없어 객관적인 평가 및 교정이 어려운 실정이다. 코즈믹 레이 중성자 탐지센서(cosmic-ray neutron probe, CRNP)를 활용한 토양수분 관측소는 위성 자료의 검보정을 위한 기준 자료 생산에서 핵심적인 역할을 수행할 수 있다. CRNP는 비침습식으로 설치가 가능하여 토양층 교란과 식생 환경의 피해를 최소화할 수 있고, 공간 대표성을 가진 중간 규모의 관측 범위를 가지고 있다는 장점이 있다. 이러한 특징은 지형이 복잡하고 식생이 우거진 지형이 많은 우리나라에서의 활용이 용이하다는 장점으로 이어진다. 따라서 본 연구는 한국형 코즈믹 레이 토양수분 관측 시스템(Korean cOsmic-ray Soil Moisture Observing System, KOSMOS) 구축의 일환으로, CRNP를 활용한 토양수분 관측소의 국내 적용성을 평가하고자 수행되었다. CRNP 관측소는 전력 및 설치 부지 확보의 용이성과 추후 타 수문기상 인자와의 효율적 활용을 고려하여, 한강홍수통제소의 홍천군 군업리 관측소에 병행 설치되었다. CRNP 토양수분 자료의 평가를 위해 12개소의 지점 토양수분 센서를 추가로 설치하였으며, 시간 안정성 분석을 통해 공간적 대표성을 평가하였다. CRNP에서 생성되는 중성자는 평균 1,087 counts per hour 정도로 설마천 관측소에 비해 낮게 나타나 홍천 관측소의 환경이 더 습윤한 환경임을 알 수 있었다. 관측된 중성자 자료의 중성자 보정과 초기교정을 통해 토양수분을 산정하였으며, 산정된 토양수분 자료는 짧은 교정 기간에도 지점 자료와의 검증에서 r=0.82로 높은 상관성을 보여주었고, root mean square error=0.02 m3/m3의 높은 정확도를 보여주었다. 추후 계절성을 반영할 수 있도록 연간 자료가 축적된 후 재교정을 수행하면 보다 높은 정확도를 보여줄 것으로 판단된다. 이러한 결과는 CRNP 토양수분 자료의 우수성을 검증한 선행연구들과 더불어, KOSMOS 구축 시 양질의 토양수분 자료를 생산할 수 있음을 시사한다.