• Title/Summary/Keyword: Flow turning

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A Study on Characteristics of Korean Community Cinema : Focusing on the history of the Korean alternative screening movement (한국 커뮤니티 시네마 특성 연구:한국 대안상영 운동의 역사를 중심으로)

  • Jeon, Byoungwon
    • The Journal of the Convergence on Culture Technology
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    • v.8 no.4
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    • pp.227-238
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    • 2022
  • This paper studies the change process and characteristics of the 'Korean community cinema movement'. The community cinema movement that has been active since the 2010's can be said to be a turning point in the Korean film culture movement. However, academic and policy definitions and research on the community cinema movement are extremely insufficient and only appear in some seminars or policy research reports. This study aims to discover the characteristics of the 'Korean community cinema movement' in the flow of the Korean alternative screening movement. A comparative study through a diachronic approach to the Korean alternative screening movement and case analysis of community cinema is intended to identify the characteristics of Korean community cinema and suggest policy measures for which a support system has not yet been prepared.

The Technique of Estimating the Right-Turn Adjustment Factor (우회전 보정계수 산정기법)

  • Kim, Gyeong-Hwan;Kim, Yeong
    • Journal of Korean Society of Transportation
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    • v.19 no.4
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    • pp.73-84
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    • 2001
  • Korean Highway Capacity Manual applies 7 adjustment factors to estimate saturation flows at signalized intersections. Among the adjustment factors, the right-turn adjustment factor uses equation hard to understand and requires complicated computing process comparing other adjustment factors. Thus. this study was conducted in order to suggest a new technique of estimating the right-turn adjustment factor which is easy to understand and simple to computer by having reasonable degree of accuracy. In this study the right-turn saturation flow ratios which are important in estimating the factor are suggested and the equation to estimate the volume of right-turn on red signal(RTOR) is developed based on observed data. The right-turn saturation flow rates can be estimated according to turning radius and number of lanes of crossing road dividing right-turn lanes into canalized and uncanalized lanes. The RTOR volume is estimated using the proportion of the time during which RTOR is possible to the whole time of red signal according to the through traffic volume per lane of the approach at signalized intersections. The technique of estimating the right-turn adjustment factor suggested in this study, which follows the HCM2000 of U.S. in principal, first judges the right-turn lane to be used exclusively for right-turn or not by employing the RTOR factor and the judging equation developed in this study. Next, if the right-turn lane is not exclusive right-turn lane, the shared right-turn lane is classified into single lane approach or multi lane approach. Thus, a total of three methods of estimating the right-turn adjustment factor to the three cases are suggested in this study.

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A Basic Study on Establishment of Sea Trial Prohibition Waterway Based on Marine Traffic Survey (해상교통량 조사 기반 시운전금지해역 설정 기초 연구)

  • Park, Young-Soo;Kim, Jin-Kwon;Kim, Jong-Sung;Kim, Jong-Soo;Lee, Yun-Sok;Park, Sang-Won
    • Journal of Advanced Marine Engineering and Technology
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    • v.39 no.3
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    • pp.318-325
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    • 2015
  • Korea has very strong shipbuilding industry in the world, so many new ships are constructed in Korean shipyards. These built vessels are carrying out sea trial at sea before delivering to shipowner, and sea trial ships cause navigation risk to other passing vessels to accomplish sea trial tests as quick turning, zigzag maneuvering and crash astern etc. in traffic congestion conditions. It occurred more than 1 collision accident related sea trial for recent 5 years. It has been increased about 30% of risk because of navigation of sea trial vessel by marine traffic flow simulation. This paper analyzed marine traffic density surveyed by AIS data for 7 days, and investigated position of marine accidents for 5 years in Korean coastal waterway, it established the sea trial prohibition areas as 10/100 level of total marine traffic volume, which is considered no danger for ship operator. This analyzed maritime safety law for setting of the prohibition waters to propose the basic legal system. It makes contribution to marine pollution prevention by setting of the sea trial prohibition water to improve the ship's navigation safety.

A Study on the Ship's Speed Control and Ship Handling at Myeongnayang Waterway (명량수도 해역에서 항해속력 규제와 선박운용에 관한 연구)

  • Kim, Deug-Bong;Jeong, Jae-Yong;Park, Young-Soo
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.20 no.2
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    • pp.193-201
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    • 2014
  • This study provided safe sailing speed and appropriate passing time to areas of known strong current water to prevent marine accident of the ships. To the interpretation of these data which target Myeongnyang waterway, AIS data of the ship was collected from $12^{th}$ July to $15^{th}$ July 2010 and site environment was investigated on $4^{th}$ September 2010. On the basis of the collected data, the 'Minimum Navigation Speed' and 'Optimum Navigation Speed' were calculated. It has also considered the 'Spare control force' or allowance and the 'Respond Rudder Angle' for each tidal current speed. Additionally, it suggested the safe passing time to strong current area by analyzing tidal level and tidal current speed. The conclusion of the research are as follows : (1) If the flow rate is greater than 4.4 kn, it is difficult for the model ship to control herself by her own steering power and to cope with tidal current pressure force and yaw moment caused by the tidal current.. (2) The minimum navigation speed should be over 2.3 times the tidal current and the optimum navigation speed should be over 4.0 times the tidal current. (3) When spring tide, the optimum passing time at Myeongnyang waterway is between 30 minutes to 1 hour before the time of high/low water, and at 5 hours after high/low water, passing of ships should be avoided because it is time when the flow rate is over 4 kn.

Estimation of Permeability and Initial Pressure in Reservoir by DFIT Data Analysis (DFIT 자료 해석을 통한 저류층의 투과도 및 초기압력 추정)

  • Kim, Tae Hong;Lee, Sung Jun;Lee, Kun Sang
    • Tunnel and Underground Space
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    • v.23 no.3
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    • pp.169-179
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    • 2013
  • Well testing in unconventional reservoirs, such as tight or shale gas formations, presents considerable challenges. It is difficult to estimate the reservoir properties in ultra-low permeability formation because of poor inflow prior to stimulation and excessive test duration. Moreover, radial flow may not develop in hydraulically fractured horizontal wells. For these reasons, the cost of test is high and the accuracy is relatively low. Accordingly, industry is turning to an alternate testing method, diagnostic fracture injection test (DFIT), which is conducted prior to the main hydraulic fracture treatments. Nowadays, DFIT are regarded as the most practical way to obtain good estimates of reservoir properties in unconventional reservoirs. Various methods may be used for interpreting DFIT data. This paper gives an explanation of those methods in detail and examines three actual field data. These show how various analysis methods can be applied to consistently interpret fracture closure pressure and time, as well as before and after closure flow regimes and reservoir properties from field data.

Development of a Solar Collector Performance of Cylindrical Parabolic Concentrating Solar Collector (태양열(太陽熱) 집열기개발(集熱器開發)에 관(關)한 연구(硏究) - 포물반사곡면(抛物反射曲面)으로된 2차원(二次元) 집광식(集光式) 태양열(太陽熱) 집열기(集熱器)의 성능분석(性能分析) -)

  • Song, Hyun Kap;Yon, Kwang Seok;Cho, Sung Chan
    • Journal of Biosystems Engineering
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    • v.10 no.1
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    • pp.54-68
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    • 1985
  • It is desirable to collect the solar thermal energy at relatively high temperature in order to minimize the size of thermal storage system and to enlarge the scope of solar thermal energy utilization. So far the concentrating solar collector has been developed to collect solar thermal energy at relatively high temperature, but it has some difficulties in maintaining the volumetric body of solar collector for long term utilization. On the other hand, the flat-plate solar collector has been developed to collect the solar thermal energy at low temperature, and it has advantages in maintaining the system for long term utilization, since it's thickness is thin and not volumetric. In this study, to develop a solar collector that has both advantages of collecting solar thermal energy at high temperature and fixing conveniently the collector system for long term period, a cylindrical parabolic concentrating solar collector was designed, which has two rows of parabolic reflectors and thin thickness such as the flat-plate solar collector, maintaining the optical form of concentrating solar collector. The characteristics of the concentrating parabolic solar collector newly designed was analysed and the results are summarized as follows; 1. The temperature of the air enclosed in solar collector was all the same as $50^{\circ}C$ in both cases of the open and closed loop, and when the heat transfer fluid was not circulated in tubular absorber, the maximum surface temperature of the absorber was $118-120^{\circ}C$, this results suggested that the heat transfer fluid could be heated up to $118^{\circ}C$. 2. In case of longitudinal installation of the solar collector, the temperature difference of heat transfer fluid between inlet and outlet was $4^{\circ}-6^{\circ}C$ at the flow rate of $110-130{\ell}/hr$, and the collected solar energy per unit area of collector was $300-465W/m^2$. 3. The collected solar energy per unit area for 7 hours was 1960 Kcal/$m^2$ for the open loop and 220 Kcal/$m^2$ for the closed loop. Therefore it is necessary to combine the open and closed loop of solar collectors to improve the thermal efficiency of solar collector. 4. The thermal efficiency of the solar collector (C.P.C.S.C.) was proportional to the density of solar radiation, indicating the maximum thermal efficiency ${\eta}_{max}=58%$ with longitudinal installation and ${\eta}_{max}=45%$ with lateral installation. 5. The thermal efficiency of the solar collector (C.P.C.S.C.) was increased in accordance with the increase of flow rate of heat transfer fluid, presenting the flow rate of $110{\ell}/hr$ was the value of turning point of the increasing rate of the collector efficiency, therefore the flow rate of $110{\ell}/hr$ was considered as optimum value for the test of the solar collector (C.P.C.S.C.) performance when the heat transfer fluid is a liquid. 6. In both cases of longitudinal and lateral installation of the solar collector (C.P.C.S.C.), the thermal efficiency was decreased linearly with an increase in the value of the term ($T_m-T_a$)/Ic and the increasing rate of the thermal efficiency was not effected by the installation method of solar collector.

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Water Masses and Frontal Structures in Winter in the Northern East China Sea (동중국해 북부해역의 겨울철 수계와 전선구조)

  • 손영태;이상호;이재철;김정창
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.8 no.3
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    • pp.327-339
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    • 2003
  • During the winter in February 1998, January and April 1999, interdisciplinary research was conducted in a large area including the South Sea of Korea and northern East China Sea to examine distribution and structure. Water masses identified from the observed data are Warm Water originated from Tsushima Warm Current, Yellow Sea Cold Water (Northern or Central Cold Water) and Korean Southern Sea Cold Water. In the southern Yellow Sea, Warm Water originated from Tsushima Warm Current, flowing into the Cheju Strait after turning around the western Cheju Island, makes a front of '┍' shape, which is bounded by the Yellow Sea Central Cold Water in the southern part of Daeheuksan Island and by the Yellow Sea Northern Cold Water in the eastern part of the Yangtze Bank. This front changes its corner shape and position with strength of the warm water extension toward northwestern Yellow Sea. The position and structure of the fronts off the southwestern tip of the Korean peninsular and near the Yangtze Bank varies with observation period. In the front in the South Sea of Korea, cold coastal water which if formed independently due to local cooling, ,sinks along the sloping bottom. We explained the processes of variations in the distribution and structure of these winter fronts in terms of up-wind and down-wind flow by the seasonal monsoon, heat budget through the sea surface and density difference across the fronts.

A Study on Environmental Impact Assessment System of Seoul City (서울시 환경영향평가 제도에 대한 연구)

  • Kim, Im-Soon;Han, Sang-Wook
    • Journal of Environmental Impact Assessment
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    • v.16 no.6
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    • pp.467-483
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    • 2007
  • Environmental Impact Assessment (EIA) is a kind of planning technique to seek ways to minimize environmental impact, a scheme to encourage sustainable development. With the launch of the Ministry of Environment in 1980, the EIA was introduced in Korea. Its full operation was initially driven by regulations on documenting EIA reports in 1981, which was piloted as a decision-making scheme where final decision were made at the development department after considering opinions suggested by the Ministry of Environment. At that time, dominance of the economic logic overwhelmed environ-friendly opinions, but thanks to the fourth revision of the Environmental Conservation Law in 1986, private projects came to be included on the EIA list. This was a turning point for the EIA to become a regulatory system. Local governments are also conducting the EIA regardless of the national-level EIA. In order to prevent and resolve increasingly severe environmental problems in Seoul in advance due to various construction projects, the Seoul Metropolitan Government, for the first time as a local government in Korea, legislated city decrees to introduce the EIA which has been underway from September 1, 2002. In particular, the Seoul government, unlike the Ministry of Environment, has included construction works on the list of evaluation projects, adopting the scoping and screen procedure scheme. In addition, complementing operational setbacks, the city government has revised and implemented decrees and enforcement laws on the Impact Assessment on Environment, Transportation and Disasters by shortening the consultation period, eliminating the submission of reports on construction, and expanding the waiver requirements in consultation over the reports. Therefore, development measures for the EIA scheme of the Seoul Metropolitan Government will be the target of the research. To that end, the up-to-date data of the Ministry of Environment, the Seoul government and local governments was collected, and latest materials from the EU, previous research and the Internet were gathered for analyses. By doing so, the flow of the EIA was reviewed, and the EIA schemes of local governments under the national EIA were analyzed. Furthermore, based on the Seoul government's recent data on the EIA based on the decrees, the background and legislation of the Seoul government's EIA were analyzed along with the developments for the environmental organizations. Setbacks were derived from the implementation period, evaluation procedures, consultation period and details of the EIA, and corresponding development measures were proposed.

Research on Vocalization for Korean Pop Song: Case Foom The YongPhil Cho's "A Lady out of Window" (대중가요 발성법 연구: 조용필의창밖의 여자중심으로)

  • Cho, Tae-Seon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.10 no.10
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    • pp.3004-3010
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    • 2009
  • The Korean pop music people enjoy today is mostly based on the pop music from foreign countries. Therefore, not only is the history very short, but also not much research is done in the Korean pop music field. Especially in terms related with the singing method, in other words the breathing and vocalization of Korean singers, it is difficult to define where it is actually situated. To add a little, it seems as if it is swarming somewhere in the middle of Korean traditional music singing methods and classical music vocalization. As pop music made its way into Korea, Korean singers had to go through many trial and errors to sing the songs of singers that had different physical conditions. Singers getting vocal nodules because of excessive vocalization, was not a surprise at that time. Yongphil Jo, a Korean singer, wanted to overcome his limits and maximize his vocal abilities. He found the answers in Korean traditional music. One of his representative songs, "The lady out the window", is one of Jo's title songs and it is the song that made a turning point in the Korean pop music vocalization. The purpose of this research is to understand the circumstances of Korean pop music through the periodical and musical background of the past and find out why the song (The lady out the window) was such an epochal vocal method at that time. Moreover, this paper covers how the breathing and vocalization is expressed by analyzing the flow, the emotional expressions, and the techniques of "The lady out the window."

The study of Efficient Treatment Conditions on the Composting of Foodwaste (음식쓰레기의 퇴비화공정의 적정운전조건 검토)

  • Kang, Chang-Min;Kim, Byoung-Man;Jeoung, Il-hyun
    • Journal of the Korea Organic Resources Recycling Association
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    • v.11 no.2
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    • pp.117-124
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    • 2003
  • The purpose of this study was to investigate the optical conditions to satisfied the salt concentration of 1% below of compost produced by using the material of foodwaste and sawdust. We changed the mixing ratios of foodwaste : sawdust from 7:3 to 3:7 and the ratios of foodwaste : rice hull from 6.5:3.5 to 4:6. We analyzed C/N, pH, temperature, water content, volatile solid, salt, heavy metals to check the degree of composting. The running conditions of composting were $80{\sim}133{\ell}/min{\cdot}m^{3}$ of air flow rate, 1:4 of time interval(on:off) and 7days of turning interval. Running times were 28days. The optical mixing ratio of foodwaste : sawdust was 6:4 when we compared many factors. Especially when the mixing ratios of foodwaste : sawdust or foodwaste : sawdust were 7:3 or 6:4, the composting was not accomplished by the reason of low C/N. The concentrations of heavy metal were sufficiently low to satisfied the satandard of organic compost. The salt concentration was 0.43%-0.46% that was the half of initial concentration. The rice hull was the good in pore rate and 통기성, and so it can used alternative material.

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