• Title/Summary/Keyword: and system dynamics

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Spatial Characteristics of Media Cluster in Seoul: Co-Evolution and Changes in Film and Broadcast TV Production (서울 영상산업 클러스터의 공간적 특성: 영화산업과 방송산업의 성장과 집적지 변화)

  • Kyung Won Lee;U-Seok Seo
    • Journal of the Economic Geographical Society of Korea
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    • v.26 no.3
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    • pp.202-222
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    • 2023
  • This study traces the growth and changes in the spatial distribution and characteristics of media cluster in Seoul by focusing on the co-evolution of film and TV production. To identify the spatial distribution and aggregation of film and broadcast TV production, we measure their spatial auto-correlation based on Moran's I and LISA, using the data from the Census on Establishments of the National Statistical Office. In addition, the eleven semi-structured interviews conducted with workers in the media industries, such as film crews and TV drama producers, help to clarify the complexity and dynamics of diverse factors that affect spatial distribution of media cluster. This multi-method study shows the increasing polycentricity of media cluster in the last decade. Gangnam, Mapo, Yeouido, Gangseo-Yeongdeungpo, and Seongsu have emerged as key hubs for media industries, particularly in light of changes in the transportation system and the real estate market. The finding indicates the co-evolution of film and broadcast TV production, demonstrating how the characteristics of the creative industry and metropolitan changes are intertwined with each other in shaping the geographical pattern of the media cluster.

Heart Rate Variability in Patients with Coronary Artery Disease (관상동맥질환 환자의 심박동변이도)

  • Kim Wuon-Shik;Bae Jang-Ho;Choi Hyoung-Min;Lee Sang-Tae
    • Science of Emotion and Sensibility
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    • v.8 no.2
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    • pp.95-101
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    • 2005
  • This study is based on previous information regarding reduced cardiac vagal activity in patients with coronary artery disease(CAD), on reduced variance(SDNN : standard deviation of all normal RR intervals), low-frequency power(LF), and the complexity of heart rate variability(HRV) in patients with chronic heart failure(CHF), and on the normalized high-frequency power of HRV is the highest in the right lateral decubitus position among 3 recumbent postures in patients with CAD, However, nothing is known about the nonlinear dynamics of HRV for the 3 recumbent postures in patients with CAD. To investigate the linear and non-linear characteristics of HRV in patients with CAD, 29 patients as CAD group and 23 patients as control group were studied. Electrocardiogram(ECG) with lead II channel was measured on these patients for 3 recumbent postures in random order. The HRV from ECG was analyzed with linear method(for time and frequency domains) and nonlinear method. The lower the high-frequency power in normalized unit(nHF) in the supine or left lateral decubitous position, the higher the increase in nHF when the position was changed from supine or left lateral decubitous to right lateral decubitous. Among the 3 recumbent postures in patients with severe CAD, the right lateral decubitus position was observed to induce the highest vagal modulation, the lowest sympathetic modulation, and the highest complexity of human physiology system.

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Functional Defects of Hb Kempsey (${\beta}99Asp{\rightarrow}Asn$) Can be Compensated by Insertion of a New Intersubunit Hydrogen Bond at the ${\alpha}_1{\beta}_2$ Subunit Interface

  • Yeh, Byung-Il;Choi, Jong-Whan;Sohn, Joon-Hyung;Lee, Hyean-Woo;Han, Dong-Pyou;Jung, Seun-Ho;Kim, Hyun-Won
    • BMB Reports
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    • v.31 no.6
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    • pp.590-594
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    • 1998
  • X-ray crystallographic studies of the deoxy form of human adult hemoglobin (Hb A) have shown that ${\beta}99Asp$ is hydrogen bonded to both ${\alpha}42Tyr$ and ${\alpha}97Asn$ in the ${\alpha}_1{\beta}_2$ subunit interface, suggesting that the essential role of ${\beta}99Asp$ is to stabilize the deoxy-Hb by creating the intersubunit hydrogen bond. In particular, for Hb Kempsey (${\beta}99Asp{\rightarrow}Asn$), molecular dynamics simulation indicated that a new hydrogen bond involving ${\beta}99Asn$ can be induced by replacing ${\alpha}42Tyr$ with a strong hydrogen-bond acceptor such as Asp. Designed mutant recombinant (r) Hb (${\beta}99Asp{\rightarrow}Asn$, ${\alpha}42Tyr{\rightarrow}Asp$) have been produced in the Escherichia coli expression system and have shown that functional defects of Hb Kempsey could be compensated by the ${\alpha}42Tyr{\rightarrow}Asp$ substitution. However, as the ${\alpha}42 Tyr{\rightarrow}Asp$ mutation has never been reported before, it is still possible that the functional properties of r Hb (${\beta}99Asp{\rightarrow}Asn$, ${\alpha}42Tyr{\rightarrow}Asp$) may be due to the mutation itself. Thus, it is required to produce r Hb (${\alpha}42Tyr{\rightarrow}Asp$) and r Hb Kempsey (${\beta}99Asp{\rightarrow}AsnX$( as controls, and to compare their properties with those of r Hb (${\beta}99Asp{\rightarrow}Asn$, ${\alpha}42Tyr{\rightarrow}Asp$). r Hb (${\alpha}42Tyr{\rightarrow}Asp$) could not be purified because it is an unstable hemoglobin which forms Heinz bodies. r Hb Kempsey (${\beta}99Asp{\rightarrow}Asn$) exhibits very high oxygen affinity and greatly reduced cooperativity. Thus, r Hb (${\beta}99Asp{\rightarrow}Asn$) and r Hb (${\alpha}42Tyr{\rightarrow}Asp)$ compensate each other.

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3D Modeling of Turbid Density Flow Induced into Daecheong Reservoir with ELCOM-CAEDYM (ELCOM-CAEDYM을 이용한 대청댐 유입탁수의 3차원 모델링)

  • Chung, Se-Woong;Lee, Heung-Soo;Ryoo, Jae-Il;Ryu, In-Gu;Oh, Dong-Geun
    • Journal of Korea Water Resources Association
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    • v.41 no.12
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    • pp.1187-1198
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    • 2008
  • Many reservoirs in Korea and their downstream environments are under increased pressure for water utilization and ecosystem management from longer discharge of turbid flood runoff compared to a natural river system. Turbidity($C_T$) is an indirect measurement of water 'cloudiness' and has been widely used as an important indicator of water quality and environmental "health". However, $C_T$ modeling studies have been rare due to lack of experimental data that are necessary for model validation. The objective of this study is to validate a coupled three-dimensional(3D) hydrodynamic and particle dynamics model (ELCOM-CAEDYM) for the simulation of turbid density flows in stratified Daecheong Reservoir using extensive field data. Three different groups of suspended solids (SS) classified by the particle size were used as model state variables, and their site-specific SS-$C_T$ relationships were used for the conversion between field measurements ($C_T$) and state variables (SS). The simulation results were validated by comparing vertical profiles of temperature and turbidity measured at monitoring stations of Haenam(R3) and Dam(R4) in 2004. The model showed good performance in reproducing the reservoir thermal structure and propagation of stream density flow, and the magnitude and distribution of turbidity in the reservoir were consistent with the field data. The 3D model and turbidity modeling framework suggested in this study can be used as a supportive tool for the best management of turbidity flow in other reservoirs that have similar turbidity problems.

Numerical Simulation of Ocean - Ice Shelf Interaction: Water Mass Circulation in the Terra Nova Bay, Antarctica (해양-빙붕 상호작용을 고려한 남극 테라노바 만에서 수괴 형성과 순환의 수치 시뮬레이션)

  • Taekyun, Kim;Emilia Kyung, Jin;Ji Sung, Na;Choon Ki, Lee;Won Sang, Lee;Jae-Hong, Moon
    • Ocean and Polar Research
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    • v.44 no.4
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    • pp.269-285
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    • 2022
  • The interaction between ocean and ice shelf is a critical physical process in relation to water mass transformations and ice shelf melting/freezing at the ocean-ice interface. However, it remains challenging to thoroughly understand the process due to a lack of observational data with respect to ice shelf cavities. This is the first study to simulate the variability and circulation of water mass both overlying the continental shelf and underneath an ice shelf and an ice tongue in the Terra Nova Bay (TNB), East Antarctica. To explore the properties of water mass and circulation patterns in the TNB and the corresponding effects on sub ice shelf basal melting, we explicitly incorporate the dynamic-thermodynamic processes acting on the ice shelf in the Regional Ocean Modeling System. The simulated water mass formation and circulation in the TNB region agree well with previous studies. The model results show that the TNB circulation is dominated by the geostrophic currents driven by lateral density gradients induced by the releasing of brine or freshwater at the polynya of the TNB. Meanwhile, the circulation dynamics in the cavity under the Nansen Ice shelf (NIS) are different from those in the TNB. The gravity-driven bottom current induced by High Salinity Shelf Water (HSSW) formed at the TNB polynya flows towards the grounding line, and the buoyance-driven flow associated with glacial meltwater generated by the HSSW emerges from the cavity along the ice base. Both current systems compose the thermohaline overturning circulation in the NIS cavity. This study estimates the NIS basal melting rate to be 0.98 m/a, which is comparable to the previously observed melt rate. However, the melting rate shows a significant variation in space and time.

A Study on Gamification Marketing based on Social Network Service (소셜네트워크 서비스 기반 게이미피케이션 마케팅 연구)

  • Moon, Ha Na;Park, Seung Ho
    • Design Convergence Study
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    • v.15 no.2
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    • pp.17-35
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    • 2016
  • Along with popularization of smart phone and routinization of social network service, enterprises are using several social network services as a marketing channel to raise brand awareness and conduct PR. Enterprises have been utilizing an element of 'Gamification' representing a functional aspect and emotional pleasure of a game in order to attract users' attention and increase their voluntary participation since the early social network service marketing. However, social network service system contains functional roles of Gamification components rather than they function separately. Hence, this research intends to examine Gamification elements of social network service and characteristics occurred when enterprise uses several social network services as a marketing channel. Besides, it aims at suggesting a marketing guideline for Gamification based on social network that may induce users' interest and increase an immersion effect. Firstly, this study examined concepts and characteristics of social network service and Gamification centered on literature research. Secondly, it summarized a game mechanics, dynamics and a fun type of Gamification components. Thirdly, based on theoretical research, it collected Gamification marketing cases of 5 enterprises including 'Coca Cola Korea', 'Lotte Mart', 'Canon Korea', "Kolon Sports' and 'Uniqlo Korea' that utilize more than 3 of 4 social network services including 'Kakao Story', 'Band', 'Facebook' and 'Instagram' used the most in our nation, analyzing characteristics of Gamification marketing and deriving a suggestion. Finally, it suggested a guideline for Gamification and social network service to build a foundation for a Gamification marketing plan through social network service.

Effect of Particulate Matter and Ash Amount on Pressure Drop and Flow Uniformity of Diesel Particulate Filter Reduction System (입자상물질과 Ash양이 디젤매연여과장치 내의 배압 및 유동균일도에 미치는 영향)

  • Kim, YunJi;Han, DanBee;Seo, TaeWon;Oh, KwangChul;Baek, YoungSoon
    • Clean Technology
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    • v.26 no.1
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    • pp.22-29
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    • 2020
  • Recently, as the fine dust is increased and the emission regulations of diesel engines have been tightened, interest in diesel soot filtration devices has rapidly increased. There is specifically a demand for the technological development of higher diesel exhaust gas after-treatment device efficiency. As part of this, many studies were conducted to increase exhaust gas treatment efficiency by improving the flow uniformity of the exhaust gas in the diesel particulate filter (DPF) and reducing the pressure drop between the inlet and the outlet of DPF. In this study, the effects of pressure drop by the flow rate and temperature of exhaust gas, DPF I/O ratio, Ash, and PM amount in diesel reduction device were simulated via a 12" diameter DPF and diesel oxidation catalyst (DOC) using ANSYS Fluent. As the flow rate and temperature decreased, the pressure drop decreased, whereas the PM amount affected the pressure drop more than the ash amount and the pressure drop was lower in anisotropic DPF than isotropic DPF. In the case of DPF flow uniformity, it was constant regardless of the various variables of DPF. In ESC and ETC conditions, the filtration efficiency for PM was similar regardless of anisotropic and isotropic DPF, but the filtration efficiency for PN (particle number) was higher in anisotropic DPF than isotropic DPF.

The Effects of Sidecar on Index Arbitrage Trading and Non-index Arbitrage Trading:Evidence from the Korean Stock Market (한국주식시장에서 사이드카의 역할과 재설계: 차익거래와 비차익거래에 미치는 효과를 중심으로)

  • Park, Jong-Won;Eom, Yun-Sung;Chang, Uk
    • The Korean Journal of Financial Management
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    • v.24 no.3
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    • pp.91-131
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    • 2007
  • In the paper, the effects of sidecar on index arbitrage trading and non-index arbitrage trading in the Korean stock market are examined. The analyses of return, volatility, and liquidity dynamics illustrate that there are no distinct differences for index arbitrage group and non-index arbitrage group surrounding the sidecar events. For further analysis, we construct pseudo-sidecar sample and analyse the effects of the actual sidecar and pseudo-sidecar on arbitrage sample and non-index arbitrage sample. The result of analysis using pseudo-sidecar shows that the differences between index arbitrage group and non-index arbitrage group are larger in pseudo-sidecar sample than in actual sidecar sample. This means that former results can be explained by temporary order clustering in one side before and after the event. Sidecar has little effect on non-index arbitrage group, however, it has relatively large effect on arbitrage group. These results imply that it needs to redesign the sidecar system of the Korean stock market which applies for all program trading including arbitrage and non-index arbitrage trading.

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Relationship between a Dense Population of Cyanobacteria and Odorous Compounds in the North Han River System in 2014 and 2015 (북한강 수계에 출현한 남조류와 이취미의 상관관계)

  • Byun, Jeong-Hwan;Hwang, Soon-Jin;Kim, Baik-Ho;Park, Jin-Rak;Lee, Jae-Kwan;Lim, Byung-Jin
    • Korean Journal of Ecology and Environment
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    • v.48 no.4
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    • pp.263-271
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    • 2015
  • To evaluate the relationship between dynamics of cyanobacteria and odorous compounds, a monthly monitoring of water quality and phytoplankton were conducted at the three serial lakes (Lake Ui-am, Lake Cheong-pyeong and Lake Pal-dang) in the North Han River for 11 times from May 2014 to March 2015. In the three serial lakes, phytoplankton communities showed that seasonal changes in Bacillariophyceae-Cyanophyceae-Bacillariophyceae. Anabaena and Pseudanabaena were dominant species in August and September 2014. At the same time the odors (Geosmin, 2-MIB) were also detected with high concentration. Relationship between environmental factors and cyanobacterial abundance showed a significant correlation with Anabaena circinalis and geosmin (r=0.983, p<0.01). In the case of Pseudanabaena limnetica showed a significant correlation of total nitrogen (r=0.685, p<0.01) and NO3-N (r=0.723, p<0.01). In addition, similarly Pseudanabaena limnetica and 2-MIB (r=0.717, p<0.01) was high. The odorous compounds appeared in the North Han River water were considered to be a direct relationship with cyanobacteria.

Optimal DO Setpoint Decision and Electric Cost Saving in Aerobic Reactor Using Respirometer and Air Blower Control (호흡률 및 송풍기 제어 기반 포기조 최적 DO 농도 설정과 전력 비용 절감 연구)

  • Lee, Kwang Su;Kim, Minhan;Kim, Jongrack;Yoo, Changkyoo
    • Korean Chemical Engineering Research
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    • v.52 no.5
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    • pp.581-586
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    • 2014
  • Main objects for wastewater treatment operation are to maintain effluent water quality and minimize operation cost. However, the optimal operation is difficult because of the change of influent flow rate and concentrations, the nonlinear dynamics of microbiology growth rate and other environmental factors. Therefore, many wastewater treatment plants are operated for much more redundant oxygen or chemical dosing than the necessary. In this study, the optimal control scheme for dissolved oxygen (DO) is suggested to prevent over-aeration and the reduction of the electric cost in plant operation while maintaining the dissolved oxygen (DO) concentration for the metabolism of microorganisms in oxic reactor. The oxygen uptake rate (OUR) is real-time measured for the identification of influent characterization and the identification of microorganisms' oxygen requirement in oxic reactor. Optimal DO set-point needed for the micro-organism is suggested based on real-time measurement of oxygen uptake of micro-organism and the control of air blower. Therefore, both stable effluent quality and minimization of electric cost are satisfied with a suggested optimal set-point decision system by providing the necessary oxygen supply requirement to the micro-organisms coping with the variations of influent loading.