• Title/Summary/Keyword: 기술관리

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Process Design of Carbon Dioxide Storage in the Marine Geological Structure: I. Comparative Analysis of Thermodynamic Equations of State using Numerical Calculation (이산화탄소 해양지중저장 처리를 위한 공정 설계: I. 수치계산을 통한 열역학 상태방정식의 비교 분석)

  • Huh, Cheol;Kang, Seong-Gil
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.11 no.4
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    • pp.181-190
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    • 2008
  • To response climate change and Kyoto protocol and to reduce greenhouse gas emissions, marine geological storage of $CO_2$ is regarded as one of the most promising option. Marine geological storage of $CO_2$ is to capture $CO_2$ from major point sources(eg. power plant), to transport to the storage sites and to store $CO_2$ into the marine geological structure such as deep sea saline aquifer. To design a reliable $CO_2$ marine geological storage system, it is necessary to perform numerical process simulation using thermodynamic equation of state. The purpose of this paper is to compare and analyse the relevant equations of state including ideal, BWRS, PR, PRBM and SRK equation of state. To evaluate the predictive accuracy of the equation of the state, we compared numerical calculation results with reference experimental data. Ideal and SRK equation of state did not predict the density behavior above $29.85^{\circ}C$, 60 bar. Especially, they showed maximum 100% error in supercritical state. BWRS equation of state did not predict the density behavior between $60{\sim}80\;bar$ and near critical temperature. On the other hand, PR and PRBM equation of state showed good predictive capability in supercritical state. Since the thermodynamic conditions of $CO_2$ reservoir sites correspond to supercritical state(above $31.1^{\circ}C$ and 73.9 bar), we conclude that it is recommended to use PR and PRBM equation of state in designing of $CO_2$ marine geological storage process.

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Forage Yields of Corn-Oats Cropping System and Soil Properties as Affected by Liquid Cattle Manure (옥수수-연맥조합의 사초수량과 토양특성에 미치는 소 액상분뇨)

  • Shin, D.E.;Kim, D.A.;Park, G.J.;Kim, J.D.;Park, H.S.;Kim, S.G.
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.19 no.4
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    • pp.325-332
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    • 1999
  • A manure management plan is important for all dairy operations. This experiment was conducted to determine the effect of different nitrogen(N) application rates of liquid cattle manure on the forage quality, N recovery, and total forage yields of corn-oats cropping system and soil properties at the National Livestock Research Institute, RDA, Suweon in 1997. Eight treatments consisting of no fertilizer, chemical fertilizer $320kg\;N\;ha^{-1}$ as urea, the continuous applications of 320, 640 and $960kg\;N\;ha^{-1}$ as liquid cattle manure(LCM), the residual effects of 200, 400 and $600kg\;N\;ha^{-1}$ as liquid cattle manure were arranged in a randomized complete block design with three replications. Mean plant height of fall sown oats was 70 and 61cm at the continuous application and the residual effect plots, respectively. Mean dry matter percent of fall sown oats at the residual effect plots was higher by 0.9% than that of oats at the continuous application plots, but there were no differences among all treatments. Mean crude protein(CP), acid detergent fiber(ADF), and neutral detergent fiber (NDF) contents of fall sown oats at the continuous application plots were higher by 1.0, 1.6, and 3.1%, respectively, than those of the residual effect plots. Also, there were significant differences among treatments (P<0.05). Total forage dry matter yields of corn and oats cropping system were ranged from 11,365 to $25,668kg\;ha^{-1}$ among the treatments. The yield was orderly ranked as LCM $960kg\;N\;ha^{-1}$ > LCM $600kg\;N\;ha^{-1}$ > LCM $640kg\;N\;ha^{-1}$ > LCM $400kg\;N\;ha^{-1}$ (P<0.05). Compared with the control, manurial value(MV) was 158 and 139% for the plot of the LCM $960kg\;N\;ha^{-1}$ and that of the LCM $600kg\;N\;ha^{-1}$, respectively. N recovery percent of fall sown oats was the highest at the plot of the LCM $200kg\;N\;ha^{-1}$ by 50%, and then was higher in order of the LCM $400kg\;N\;ha^{-1}$, LCM $600kg\;N\;ha^{-1}$, and LCM $320kg\;N\;ha^{-1}$. Contents of exchangeable cation in the soil of the residual effect plots was higher than that of the continuous application plots. These results suggest that the LCM $600kg\;N\;ha^{-1}$ may be the most effective in total forage dry matter yields, manurial value, N recovery, and utilizing liquid manure N under the corn and oats double cropping system.

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Distribution and Pollution Assessment of Trace Metals in Core Sediments from the Artificial Lake Shihwa, Korea (시화호 코어 퇴적물 내 미량금속 분포 특성 및 오염 평가)

  • Ra, Kongtae;Kim, Eun-Soo;Kim, Joung-Keun;Kim, Kyung-Tae;Lee, Jung-Moo;Kim, Eu-Yeol
    • Ocean and Polar Research
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    • v.35 no.2
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    • pp.69-83
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    • 2013
  • Metal concentrations in creek water, sewer outlets and core sediments were analyzed to identify the potential origin of metal pollution and to evaluate the extent of metal pollution and potential toxicity of Lake Shihwa. Mean concentrations for dissolved metals in creek water and sewer outlets were 1.6~136 times higher than those in the surface seawater of Lake Shihwa. Metal concentrations in creek water from an industrial region were also higher than those from municipal and agricultural regions, indicating that the potential source of metal pollution in the study area might be mainly due to industrial activities. The vertical profiles of metals in core sediments showed an increasing trend toward the upper sediments. Extremely higher concentrations of metals were observed in the vicinity of Banweol industrial complex. The results of a geo-accumulation index indicated that Cu, Zn and Cd were highly polluted. By comparing the sediment quality guidelines such as TEL and PEL, six metals such as Cr, Ni, Cu, Zn, Cd and Pb levels in core sediments nearby industrial complex exceeded the PEL value. Mean PEL quotient (mPELQ) was used to integrate the estimate of potential toxicity for measured metals in the present study. Mean PELQs in core sediments from Lake Shihwa ranged from 0.2~2.3, indicating that benthic organisms nearby the industrial complex may have been adversely affected.

Estimation of Genetic Parameters for Economic Traits in Yorkshire (요크셔종에 대한 경제형질의 유전모수 추정)

  • Song, K.L.;Kim, B.W.;Kim, S.D.;Choi, C.S.;Kim, M.J.;Lee, J.G.
    • Journal of Animal Science and Technology
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    • v.44 no.5
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    • pp.499-506
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    • 2002
  • This study was conducted to estimate the heritabilities and genetic and phenotypic correlations among average daily gain, age at 90kg and backfat thickness in Yorkshire pigs. The data were obtained from 2,111 heads of Yorkshire tested at National Livestock Research Institute from May, 1994 to April, 2000. Genetic parameters were estimated with a multiple trait animal model by using DF-REML (Deri- vative-Free REstricted Maximum Likelihood). The results obtained are summarized as follows ; The means of traits studied were 0.871${\pm}$0.124 kg for average daily gain, 145.397${\pm}$11.718 days for age at 90kg and 1.476${\pm}$0.241 cm for backfat thickness. The estimated heritabilities were 0.55 for average daily gain, 0.56 for age at 90kg and 0.55 for backfat thickness. The genetic correlation of average daily gain with age at 90kg and backfat thickness were -0.82, 0.10, respectively. The genetic correlation of age at 90kg with backfat thickness was -0.25. The phenotypic correlations of average daily gain(ADG) with age at 90kg and backfat thickness and age at 90kg with backfat thickness were -0.77, 0.02 and -0.05 respectively. Though phenotypic correlation of ADG and age at 90kg was low, breeding project should be carefully considered by high genetic correlation. High heritabilities on all economic traits were obtained. Therefore, it is considered that suitable selection and management is needed successful improvement.

Analyzing the Effect of Online media on Overseas Travels: A Case study of Asian 5 countries (해외 출국에 영향을 미치는 온라인 미디어 효과 분석: 아시아 5개국을 중심으로)

  • Lee, Hea In;Moon, Hyun Sil;Kim, Jae Kyeong
    • Journal of Intelligence and Information Systems
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    • v.24 no.1
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    • pp.53-74
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    • 2018
  • Since South Korea has an economic structure that has a characteristic which market-dependent on overseas, the tourism industry is considered as a very important industry for the national economy, such as improving the country's balance of payments or providing income and employment increases. Accordingly, the necessity of more accurate forecasting on the demand in the tourism industry has been raised to promote its industry. In the related research, economic variables such as exchange rate and income have been used as variables influencing tourism demand. As information technology has been widely used, some researchers have also analyzed the effect of media on tourism demand. It has shown that the media has a considerable influence on traveler's decision making, such as choosing an outbound destination. Furthermore, with the recent availability of online information searches to obtain the latest information and two-way communication in social media, it is possible to obtain up-to-date information on travel more quickly than before. The information in online media such as blogs can naturally create the Word-of-Mouth effect by sharing useful information, which is called eWOM. Like all other service industries, the tourism industry is characterized by difficulty in evaluating its values before it is experienced directly. And furthermore, most of the travelers tend to search for more information in advance from various sources to reduce the perceived risk to the destination, so they can also be influenced by online media such as online news. In this study, we suggested that the number of online media posting, which causes the effects of Word-of-Mouth, may have an effect on the number of outbound travelers. We divided online media into public media and private media according to their characteristics and selected online news as public media and blog as private media, one of the most popular social media in tourist information. Based on the previous studies about the eWOM effects on online news and blog, we analyzed a relationship between the volume of eWOM and the outbound tourism demand through the panel model. To this end, we collected data on the number of national outbound travelers from 2007 to 2015 provided by the Korea Tourism Organization. According to statistics, the highest number of outbound tourism demand in Korea are China, Japan, Thailand, Hong Kong and the Philippines, which are selected as a dependent variable in this study. In order to measure the volume of eWOM, we collected online news and blog postings for the same period as the number of outbound travelers in Naver, which is the largest portal site in South Korea. In this study, a panel model was established to analyze the effect of online media on the demand of Korean outbound travelers and to identify that there was a significant difference in the influence of online media by each time and countries. The results of this study can be summarized as follows. First, the impact of the online news and blog eWOM on the number of outbound travelers was significant. We found that the number of online news and blog posting have an influence on the number of outbound travelers, especially the experimental result suggests that both the month that includes the departure date and the three months before the departure were found to have an effect. It is shown that online news and blog are online media that have a significant influence on outbound tourism demand. Next, we found that the increased volume of eWOM in online news has a negative effect on departure, while the increase in a blog has a positive effect. The result with the country-specific models would be the same. This paper shows that online media can be used as a new variable in tourism demand by examining the influence of the eWOM effect of the online media. Also, we found that both social media and news media have an important role in predicting and managing the Korean tourism demand and that the influence of those two media appears different depending on the country.

A Study on Significance Testing of Driver's Visual Behavior due to the VMS Message Display Forms on the Road (도로상 VMS 표출방식별 운전자 유의성 검증에 관한 연구)

  • Kum, Ki-Jung;Son, Young-Tae;Bae, Deok-Mo;Son, Seung-Neo
    • International Journal of Highway Engineering
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    • v.7 no.4 s.26
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    • pp.151-162
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    • 2005
  • Variable Message Sign (VMS), which provides drivers with direct information about state of traffic congestion and for prevent an accident, is the most effective method among the methods of providing information in Advanced Transportation Management System. Currently establishment and the VMS which is operated foundation lets in Guidelines on the use of Variable message sign (a book of the VMS) of 1999 November the Ministry Construction & Transportation, these contents mean main viewpoint on physical part such as message special quality variable (font, character size and line space, word interval) and position mainly among standard about establishment in general. But, it is true that using without effect verification on the character of VMS display and that using mode of stationary-centered. In this paper, it executed significance test to effort verification on the character of VMS display for more practical and effective information transmission based on the driver viewpoint For the researches; develop 3D-Simulation, select characteristics of driver's visual cognition behavior (the conspicuity, the legibility and the comprehensibility), evaluation each issue (day or night, 80km/h or 100km/h). Especially, that used the Eye Marker Recorder to measure of reading-time (legibility) thus, confirmed objectivity and reduce an observational error. The results showed that the conspicuity is Flashing> Stationary>Scroll. The legibility is not deference that Flashing between stationary form. Also the comprehensibility result showed that Flashing> Stationary>Stroll form.

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A study on the developmental plan of Alarm Monitoring Service (기계경비의 발전적 대응방안에 관한 연구)

  • Chung, Tae-Hwang;So, Seung-Young
    • Korean Security Journal
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    • no.22
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    • pp.145-168
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    • 2010
  • Since Alarm Monitoring Service was introduced in Korea in 1981, the market has been increasing and is expected to increase continually. Some factors such as the increase of social security need and the change of safety consciousness, increase of persons who live alone could be affected positively on Alarm Monitoring Service industry. As Alarm Monitoring Service come into wide use, the understanding of electronic security service is spread and consumer's demand is difficult, so consideration about new developmental plan is need to respond to the change actively. Electronic security system is consist of various kinds of element, so every element could do their role equally. Alarm Monitoring Service should satisfy consumer's various needs because it is not necessary commodity, also electronic security device could be easily operated and it's appearance has to have a good design. To solve the false alarm problem, detection sensor's improvement should be considered preferentially and development of new type of sensor that operate dissimilarly to replace former sensor is needed. On the other hand, to settle the matter that occurred by response time, security company could explain the limit on Alarm Monitoring System to consumer honestly and ask for an understanding. If consumer could be joined into security activity by security agent's explanation, better security service would be provided with mutual confidence. To save response time the consideration on the introduction of GIS(Global Information System) is needed rather than GPS(Global Positioning System). Although training program for security agents is important, several benefits for security agents should be considered together. The development of new business model is required for preparation against market stagnation and the development of new commodity to secure consumer for housing service rather than commercial facility service. for the purpose of those, new commodity related to home-network system and video surveillance system could be considered, also new added service with network between security company and consumer for a basis is to be considered.

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Analysis of National Stream Drying Phenomena using DrySAT-WFT Model: Focusing on Inflow of Dam and Weir Watersheds in 5 River Basins (DrySAT-WFT 모형을 활용한 전국 하천건천화 분석: 전국 5대강 댐·보 유역의 유입량을 중심으로)

  • LEE, Yong-Gwan;JUNG, Chung-Gil;KIM, Won-Jin;KIM, Seong-Joon
    • Journal of the Korean Association of Geographic Information Studies
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    • v.23 no.2
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    • pp.53-69
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    • 2020
  • The increase of the impermeable area due to industrialization and urban development distorts the hydrological circulation system and cause serious stream drying phenomena. In order to manage this, it is necessary to develop a technology for impact assessment of stream drying phenomena, which enables quantitative evaluation and prediction. In this study, the cause of streamflow reduction was assessed for dam and weir watersheds in the five major river basins of South Korea by using distributed hydrological model DrySAT-WFT (Drying Stream Assessment Tool and Water Flow Tracking) and GIS time series data. For the modeling, the 5 influencing factors of stream drying phenomena (soil erosion, forest growth, road-river disconnection, groundwater use, urban development) were selected and prepared as GIS-based time series spatial data from 1976 to 2015. The DrySAT-WFT was calibrated and validated from 2005 to 2015 at 8 multipurpose dam watershed (Chungju, Soyang, Andong, Imha, Hapcheon, Seomjin river, Juam, and Yongdam) and 4 gauging stations (Osucheon, Mihocheon, Maruek, and Chogang) respectively. The calibration results showed that the coefficient of determination (R2) was 0.76 in average (0.66 to 0.84) and the Nash-Sutcliffe model efficiency was 0.62 in average (0.52 to 0.72). Based on the 2010s (2006~2015) weather condition for the whole period, the streamflow impact was estimated by applying GIS data for each decade (1980s: 1976~1985, 1990s: 1986~1995, 2000s: 1996~2005, 2010s: 2006~2015). The results showed that the 2010s averaged-wet streamflow (Q95) showed decrease of 4.1~6.3%, the 2010s averaged-normal streamflow (Q185) showed decreased of 6.7~9.1% and the 2010s averaged-drought streamflow (Q355) showed decrease of 8.4~10.4% compared to 1980s streamflows respectively on the whole. During 1975~2015, the increase of groundwater use covered 40.5% contribution and the next was forest growth with 29.0% contribution among the 5 influencing factors.

Elementary Teachers' Perception in Using Smart-Technology in STEAM Class : Focus on Application Type, Difficulties and Support Required (STEAM 수업에서 스마트테크놀로지 적용에 대한 초등교사의 인식 -적용 유형과 어려움 및 지원을 중심으로-)

  • Han, Areum;Na, Jiyeon
    • Journal of The Korean Association For Science Education
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    • v.39 no.6
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    • pp.777-790
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    • 2019
  • The purpose of this study is to investigate the experience of teachers who apply Smart-technology in elementary school STEAM class and the reasons, difficulties when applying the technology and required support. Semi-structured in-depth interviews were conducted with six elementary school teachers with specialized knowledge in STEAM education who have experienced STEAM lessons several times before. The research findings are as follows: First, research participants utilized a variety of Smart-technology in STEAM class, most of which were experiential or interactive technology. Among the STEAM learning criteria, the Smart-technology in 'Creative Design' course was most often applied. Second, they adopted Smart Technology in STEAM class to encourage students to feel interested, actively participate in the class, enjoy indirect experience, and nurture interest in state-of-the-art technology. They used it to prepare for future societies and organize classes that are suitable for STEAM learning criteria. They also used Smart-technology because it was easy to use. Third, they found it difficult to find, secure, and use suitable Smart-technology when applying Smart-technology in the STEAM class. They also had trouble restructuring the curriculum. In addition, there were difficulties in using Smart-technology in the class such as lack of class hours, increased level of activity, insufficient physical environment and unexpected malfunction of Smart-technology, thus interrupted the class. After the class, it was hard to manage Smart-technology and also, there were difficulties in assessment, record, and negative awareness of surrounding people. Fourth, they mentioned that's suggesting education guidelines, develop, and distribute educational materials are required to enable 'Creative Design,' reduce educational content, provide training, secure Smart-technology equipment and provide Wi-Fi, support teacher's club and communities and create an atmosphere to emotionally support teachers in order to activate using Smart-technology in STEAM class.

Analysis of Knowledge and Competency for the Fourth Industrial Revolution Based on Anderson's Revision of Bloom's Taxonomy: Focused on Achievement Standard in the 2015 revised Practical Arts(Technology·Home Economics) (Bloom의 신교육목표 분류체계에 기초한 4차 산업혁명 시대에 요구하는 지식과 역량 분석: 2015 개정 실과(기술·가정) 교육과정의 가정과 성취기준을 대상으로)

  • Yang, Ji Sun;Lee, Gyeong Suk
    • Journal of Korean Home Economics Education Association
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    • v.30 no.3
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    • pp.129-149
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    • 2018
  • This study has attempted to analyze the achievement standards in the 2015 revised curriculum, based on the revision of Bloom's Taxonomy and aims to identify the knowledge and required competencies in the fourth industrial era. The results of this study are as follows: First, the knowledge dimensions was the highest 'metacognitive knowledge' in middle school, while 'factual knowledge' was the highest in high school, and 'knowledge of specific details and elements' was the highest subtype of all of the knowledge dimensions. The dimensions of the cognitive process, such as the terms 'apply' and 'analyze' in middle school, as 'understand' and 'evaluate' in high school have been treated inattentively. Second, the knowledge dimension and the cognitive process dimension according to key concepts display the metacognitive knowledge and 'understand' in development, the conceptual knowledge and 'understand' in relationship. While the 'metacognitive knowledge' and 'apply' in life culture, the 'procedural knowledge' and 'evaluate' in safety, the 'factual knowledge' and 'apply' in management and the 'metacognitive knowledge' and 'understand' in life design were extremely high. Third, the verbs used in the achievement standards displayed as 'explore', 'understand', 'analyze', 'practice', 'suggest', 'recognize' and 'evaluate'. Since the statement of the action verb is the very basis for determining the performance process, specific competencies may be achieved by reflecting on the actual achievement standards. These standards should provide us with a effective cognitive process for to understand a learner's performance skills and support the direction of the education required, through a strategy that refines the connection between content elements and functions and develop their competences for the future.