• Title/Summary/Keyword: flow control

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Development of a radiological emergency evacuation model using agent-based modeling

  • Hwang, Yujeong;Heo, Gyunyoung
    • Nuclear Engineering and Technology
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    • v.53 no.7
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    • pp.2195-2206
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    • 2021
  • In order to mitigate the damage caused by accidents in nuclear power plants (NPPs), evacuation strategies are usually managed on the basis of off-site effects such as the diffusion of radioactive materials and evacuee traffic simulations. However, the interactive behavior between evacuees and the accident environment has a significant effect on the consequential gap. Agent-based modeling (ABM) is a method that can control and observe such interactions by establishing agents (i.e., the evacuees) and patches (i.e., the accident environments). In this paper, a radiological emergency evacuation model is constructed to realistically check the effectiveness of an evacuation strategy using NetLogo, an ABM toolbox. Geographic layers such as radiation sources, roads, buildings, and shelters were downloaded from an official geographic information system (GIS) of Korea, and were modified into respective patches. The dispersion model adopted from the puff equation was also modified to fit the patches on the geographic layer. The evacuees were defined as vehicle agents and a traffic model was implemented by combining the shortest path search (determined by an A * algorithm) and a traffic flow model incorporated in the Nagel-Schreckenberg cellular automata model. To evaluate the radiological harm to the evacuees due to the spread of radioactive materials, a simple exposure model was established to calculate the overlap fraction between the agents and the dispersion patches. This paper aims to demonstrate that the potential of ABM can handle disaster evacuation strategies more realistically than previous approaches.

Electronic Government and Systematic Record Management - Based on a Methodological Application - (전자정부와 과학적 기록관리 - 방법론적 응용을 중심으로 -)

  • Kim, Ik-Han
    • The Korean Journal of Archival Studies
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    • no.2
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    • pp.49-76
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    • 2000
  • The government is pushing hard to realize the electronic and knowledge government. In connection with the efforts most public institutions have already started adopting the electronic document management system(EDMS), and have entered in a phase of modification of, and supplement to the system for the flow of the electronic documents among the agencies to be made possible by the month of November this year. The present situation is that the modification and supplement of EDMS are underway in the field that is unrelated to the records and archival management, what has been foreseen in the academic world of archival science. Under this circumstances the article places emphasis on the importance of the positive participation of the archivists in the development of the EDMS. To be concrete it reveals how the archival achievements can be practically applicable to the EDMS. What is particularly conspicuous in the article is the detailed description of how usefully control of record production, classification and description, evaluation and selection that are put into practice in the archival management law can be embodied in the development of the EDMS. Finally the article put emphasis on the positive exchanges and integration to bring the archival management science and computer science, archival management law and electronic government law, the archival management agencies and the agencies in charge of the electronic government together into whole to find a way for the methodical achievements of scientific archival management to be positively applicable to the electronic document management system(EDMS).

Enhancement of eurycomanone biosynthesis in cell culture of longjack (Eurycoma longifolia) by elicitor treatment

  • Nhan, Nguyen Huu;Loc, Nguyen Hoang
    • Journal of Plant Biotechnology
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    • v.45 no.4
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    • pp.340-346
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    • 2018
  • In this study, the effect of elicitors such as yeast extract (YE), methyl jasmonate (MeJA) and salicylic acid (SA) on the accumulation of eurycomanone in Eurycoma longifolia cell cultures were investigated. Suspension cells of E. longifolia was cultured in Murashige and Skoog (MS) medium supplemented with 30 g/L sucrose, 1.25 mg/L naphthaleneacetic acid (NAA) and 1 mg/L kinetin at a shaking speed of 120 rpm. Elicitors were added in the culture at different concentrations and times to stimulate eurycomanone accumulation in the Eurycoma longifolia cells. Eurycomanone content was determined by HPLC with a C18 column, flow rate of 0.8 mL/min, run time of 17.5 min, and a detector wavelength of 254 nm. The stationary phase was silica gel and the mobile phase was acetonitrile: $H_2O$. Non-elicited cells were used as the control. The study showed the effect of different elicitor concentrations, YE at 200 mg/L, MeJA at $20{\mu}M$ and SA at $20{\mu}M$ stimulated high production of eurycomanone. In which, treatment of $20{\mu}M$ MeJA after 4 days of culture resulted in the highest accumulation of this compound (17.36 mg/g dry weight), approximately 10-fold higher than that of untreated cells (1.70 mg/g dry weight).

Analytical Method Validation of (-)Epicatechin gallate in Penthorum chinense Pursh Extract using HPLC

  • Kwon, Jin Gwan;Jung, Yeon Woo;Seo, Changon;Hong, Seong Su;Lee, Ji Eun;Shin, Hyun Tak;Jung, Su Young;Choi, Chun Whan;Kim, Jin Kyu
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2019.04a
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    • pp.100-100
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    • 2019
  • This study attempted to establish a High Performance Liquid Chromatography (HPLC) analysis method for the determination of (-)-epicatechin gallate as a part of the quality control for the development of functional cosmetic materials from Penthorum chinense Pursh extracts. HPLC was performed on a Unison US-C18 column ($4.6{\times}250mm$, $5{\mu}m$) with a gradient elution of 0.05% (v/v) trifluoroacetic acid (TFA) and methyl alcohol at a flow rate of 1.0 mL/min at $30^{\circ}C$. The analyte was detected at 280 nm. The HPLC method was performed in accordance with the International Conference on Harmonization (ICH) guideline (version 4, 2005) of analytical procedures with respect to specificity, precision, accuracy, and linearity. The limits of detection and quantitation were 0.11 and 0.33 mg/mL, respectively. Calibration curves showed good linearity (r2 > 0.9999), and the precision of analysis was satisfied (less than 0.6%). Recoveries of quantified compounds ranged from 99.51 to 101.92%. This result indicates that the established HPLC method is very useful for the determination of marker compound in P. chinense Pursh extracts.

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Differentiated Services in Wired Ship Area Networks (선박 내 유선망에서 차등화 서비스 기술)

  • Jeon, Hwang-jong;Kim, Seong-pyo;Park, Jin-gwan;Oh, Ju-seong;Lee, Seung-Beom;Hur, Kyeong;Jeong, Min-a;Lee, Seong Ro
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2014.10a
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    • pp.165-167
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    • 2014
  • In this paper, an packet drop technique is proposed to outperform the previous RIO (RED In and Out) drop mechanism for DiffServ in ship area networks. the proposed packet drop technique does not manage the individual flows and divides them into several flow groups according to a criterion. And it guarantees the fairness between individual flows in the same QoS class through the group-based control. In simulation results of the proposed packet drop technique, the link utilization decreases than RIO. But it guarantees more data rates to DiffServ flows passing multiple bottleneck links.

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Study on Micro-bubble Generation Characteristics in Venturi Cavitation using Laser Diffractometer (레이저 회절 측정기를 이용한 벤츄리 캐비테이션에서의 마이크로버블 발생 특성 연구)

  • Lim, Yun Gyu;Yang, Hae Jeong;Kim, Yung Il
    • Journal of Drive and Control
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    • v.16 no.1
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    • pp.1-6
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    • 2019
  • The use of micro bubbles in industrial fields has been increasing in the recent years., particularly micro-bubble sterilization and water purification effects. Various methods have been developed for the generation of micro-bubbles. Depending on the method of generating bubbles, the micro-bubbles can be roughly classified into saturation molding, cavitation and rotation flow types. The objective of this study was to use ventilated tube type as a method of generating micro-bubbles in order to purify large amount of water quality such as lakes and reservoirs. This method shows a difference in efficiency in which micro-bubbles are generated depending on the contact ratio of gas to liquid. The study also investigated the optimal gas liquid contact ratio by applying various orifice methods and investigated the optimum condition of micro-bubble generation by gas Based on this, a technology to develop a micro-bubble generator with a venturi type nozzle shape that has a high water purification effect was developed.

Volatile organic compounds emitted from printing processes and their removal by adsorption (인쇄업에서 배출되는 반응성 VOCs 종류와 흡착 제거 방법의 적용)

  • Ahn, Hae Young;Lee, Yoon Kyoung;Song, Ji Hyeon
    • Journal of odor and indoor environment
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    • v.17 no.4
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    • pp.396-403
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    • 2018
  • In this study, volatile organic compounds (VOCs) emitted from printing industries were analyzed, and an inorganic adsorbent, ${\gamma}-alumina$, was selected for the effective control of the VOC emissions. Printing processes commonly require inks, thinners, and cleaners, and they were mixed organic solvents containing aromatic compounds, ketones, and alcohols. Therefore, toluene, methyl ethyl ketone (MEK), and isopropyl alcohol (IPA) were selected as model compounds for this study. The adsorptive properties using ${\gamma}-alumina$ were determined for the model compounds. Both batch isotherm and continuous flow column tests demonstrated that the adsorption capacity of MEK and IPA was 3~4 times higher than that of toluene. The column test performed at an inlet toluene concentration of 100 ppm showed that an 80% breakthrough for toluene was observed after 3 hours, but both MEK and IPA were continuously adsorbed during the same time period. A numerical model simulated that the ${\gamma}-alumina$ could remove toluene at a loading rate of 0.4 mg/min only for a 4-hour period, which might be too short of a duration for real applications. Consequently, lifetime enhancement for ${\gamma}-alumina$ must be implemented, and ozone oxidation and regeneration would be feasible options.

A Study on Improvement of Local Government Disaster Management System in Korea - Focused on Strengthening the Disaster Management Capacity of Local Government - (지방자치단체 재난관리체계 개선에 관한 연구 - 지방자치단체의 재난관리 역할 강화를 중심으로 -)

  • Hong, Ji-Wan
    • Journal of the Architectural Institute of Korea Planning & Design
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    • v.34 no.9
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    • pp.21-30
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    • 2018
  • This study aims for improving the system in Disaster Management of Local Government. In addition, the overall disaster management system was compared to the effectiveness of the disaster prevention system and reliability, and problems and improvement points were derived. The disaster management system in Korea has a structure that promptly investigates and restores damage by a simple procedure. Korea disaster management system manages information on top-down structural disasters through the flow of prevention, preparation, response, and recovery. The process from disaster response to recovery under the leadership of the central disaster safety headquarters is simplified. Disaster management tasks are dispersed among departments, making it difficult to respond promptly. Under the control of the central government, disaster management, such as disaster prevention, investigation, and recovery, are carried out. The disaster management improvement direction of the local government should establish the disaster response system focusing on the local government. Therefore, it is necessary to have budget to operate the organization - centered disaster management budget and the disaster management organization. The disaster response manual should be prepared considering the disaster environment and disaster prevention plan. In order to utilize disaster information, it is necessary to reorganize information system such as integrate and streamline of the private resource database and NDMS.

Development of Prediction Models of Dressroom Surface Condensation - A nodal network model and a data-driven model - (드레스룸 표면 결로 발생 예측 모델 개발 - 노달 모델과 데이터 기반 모델 -)

  • Ju, Eun Ji;Lee, June Hae;Park, Cheol-Soo;Yeo, Myoung Souk
    • Journal of the Architectural Institute of Korea Structure & Construction
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    • v.36 no.3
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    • pp.169-176
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    • 2020
  • The authors developed a nodal network model that simulates the flow of moist air and the thermal behavior of a target area. The nodal network model was enhanced using a parameter estimation technique based on the measured temperature, humidity, and schedule data. However, the nodal model is not good enough for predicting humidity of the target space, having 55.6% of CVRMSE. It is because re-evaporation effect could not be modeled due to uncertain factors in the field measurement. Hence, a data-driven model was introduced using an artificial neural network (ANN). It was found that the data-driven model is suitable for predicting the condensation compared to the nodal model satisfying ASHRAE Guideline with 3.36% of CVRMSE for temprature, relative humidity, and surface temperature on average. The model will be embedded in automated devices for real-time predictive control, to minimize the risk of surface condensation at dressroom in an apartment housing.

An experimental study on the stern bottom pressure distribution of a high-speed planing vessel with and without interceptors

  • Seok, Woochan;Park, Sae Yong;Rhee, Shin Hyung
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.12 no.1
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    • pp.691-698
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    • 2020
  • In this study, the effects of hydrodynamic interceptors on a high-speed vessel were investigated to identify the operating principle based on experiments. Model tests were performed using a high-speed towing carriage. The resistance, trim and rise of Center of Gravity (CG) of the high-speed vessel were measured for various ship speeds and interceptor heights. As the interceptor height increased, the trim and rise of CG were reduced. In order to quantitatively analyze these phenomena, the pressure at the stern bottom was measured using tactile sensors. The reliability of the measured results from the tactile sensors was verified through repeat tests. The pressure on the stern bottom increased in proportion to the interceptor height, as the interceptor partially blocked the flow there. Then, the trim was reduced. However, as the ship speed increases, the pressure at the location close to the interceptor decreases when the interceptor height is small, leading to increased trim. Therefore, the interceptor height for running attitude control should be carefully determined considering multiple factors in the operating condition of the high-speed planing hull.