• Title/Summary/Keyword: dispersion management

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A Study on the Separation of Membrane and Leaching of Platinum and Ruthenium by Hydrochloric Acid from MEA of Fuel Cell (연료전지용(燃料電池用) 막전극접합체(膜電極接合體)의 막분리(膜分離) 및 염산(鹽酸)에 의한 백금(白金)과 루테늄의 침출(浸出)에 관(關)한 연구(硏究))

  • Lee, Jin-A;Kang, Hong-Yoon;Ryu, Ho-Jin
    • Resources Recycling
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    • v.21 no.3
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    • pp.15-20
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    • 2012
  • In this paper, we carried out separation of membrane and leaching of Pt and Ru using hydrochloric acid from MEA(membrane-electrode assembly) of fuel cell. In this method, these were separated from MEA of fuel cell using the distilled water, 10 vol.% butanol solution and 15 vol.% cationic surfactant(Koremul-LN-7) by dipping method without the dispersion of catalyst particles. And the leaching of Pt and Ru containing in the separated carbon paper catalysts has been studied by hydrochloric acid using $HNO_3$ or $H_2O_2$ as a oxidant. The leaching ratio of Pt and Ru were higher when $H_2O_2$ was used as a oxidant and the optimum conditions were obtained in 8M HCl, the amount of $H_2O_2$ 5M and 6 hours of leaching time at $90^{\circ}C$. In this condition, extraction of Pt and Ru were 98% and 71.5%, respectively.

An Application Scheme of I-MR Control Charts for Monitoring Internet Communication Network Quality Characteristics (인터넷통신 네트워크 품질특성 모니터 링을 위한 I-MR 관리도 활용체계)

  • Park, Sung-Min;Park, Young-Joon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.10B
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    • pp.936-944
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    • 2006
  • In order to enhance their own customer satisfaction index that is one of the top level managerial performance indices, Internet communication service providers endeavor onto establishing a total quality management system. Specifically, it is under discussion that some critical Internet communication network quality characteristics closely related to customer satisfaction index should be controlled aiming to this managerial goal. This paper presents an application scheme of I-MR control charts for monitoring Internet communication network quality characteristics. This statistical quality control scheme generates a signal to practitioners when it detects the network quality characteristics out-of control. It is designed based on; 1) individual measurements; and 2) moving ranges between two consecutive individual measurements collected with a constant time interval. Empirical analyses are illustrated to estimate the expected quality improvement ratios that can be realized with the application scheme proposed in this paper. Assuming that the assignable causes can be revealed and eradicated, regarding two Internet communication services A, B, seven network quality characteristics for each service, eleven distinct measuring spots for each network quality characteristic, the expected quality improvement ratios are calculated with which the effect of the application scheme is evaluated. Results show the ranges of the expected quality improvement ratios; 1) Service A, (1) mean (0.31%-11.44%), (2) standard deviation (9.82%-71.10%): 2) Service B, (1) mean (0.29%-17.64%), (2) standard deviation (8.05%-60.59%). Hence, It is anticipated that the I-MR control charts based application scheme can be effective not only to improving the mean and dispersion of the network quality characteristics concerned but also to maintaining the network quality characteristics in-control consequently.

Conceptual Design of Metadata based Research Results Information Retrieval System (메타데이터 기반의 연구성과정보 검색시스템의 개념적 설계)

  • Park, Dong-Jin;Lee, Sang-Tae;Choi, Ki-Suk
    • Journal of Information Management
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    • v.37 no.2
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    • pp.1-20
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    • 2006
  • It has lately been recognized that the sharing and exchanging of the research results information is the critical factor to improve the research productivity. So many institutions are planning or developing the information systems which provide the research information services for researcher. But it has very difficulty in integrating the research resources information due to the dispersion and heterogeneity in data sources, and semantic and structural difference in describing data. We propose the semantic web based methodology and conceptual framework for raising the interoperability of metadata about research results information, which will support the integration of the distributed research data for information services in the end. We first introduce the ontology which is developed based on Standard Metadata of Research Results Information published by STISC. Then to show the applicability in real-world environment, we express the metadata of research information in RDF/RDFS according to ontology. Finally we proposed the conceptual architecture of research information service system which shows the main components, the functional requirements, and the principal and design direction at implementing the system.

Relationship Between the Technology Innovation Performance of IT Venture Business and CEO Characteristics (기술혁신 성과와 경영자 특성에 관한 연구: IT벤처기업을 중심으로)

  • Park, Jae-Min;Kim, Hyo-Young
    • Journal of Digital Convergence
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    • v.9 no.6
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    • pp.173-186
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    • 2011
  • In this study, the influence of the CEOs' characteristics on the technology innovation performances of IT venture companies was analyzed. The relation between business performance and the characteristics of CEOs has been dealt with in earlier studies, but most paid attention to financial perspective, and few of these focused on the influence of managers on technology innovation. On the other hand, most of the studies related to the role of managers in technology innovation mainly focused on R&D investment and research infrastructure but did not delve on the characteristics of them in an in-depth way. In this study, the characteristics of CEOs and their technology innovation performances were empirically analyzed based on the results of a recently conducted survey on the IT venture companies. In the analytical aspect, a negative binominal model was applied to solve the over-dispersion problem that often appears in the count variable analysis. As a result, it was found that major, work type, and work experience, among managers' characteristics, have significant influences on managers' technology innovation performances, along with the company's innovation capacity, technological competitiveness, market competition, and support from the government.

Spatio-temporal Distribution Pattern of New Biotypes of Weedy Rice (Oryza sativa L.) in Selangor North-West Project, Malaysia

  • Baki, B.B.;M.M., Shakirin
    • Korean Journal of Weed Science
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    • v.30 no.2
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    • pp.68-83
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    • 2010
  • Weedy rice (Oryza sativa L.) occurred sympatrically with other weeds and the rice crop in Malaysian rice granaries. We conducted field surveys in 2006-2008 seasons in 7 farm blocks of Selangor's North West Project, Malaysia to enlist the new biotypes of weedy rice (NBWR) and assess their spatio-temporal pattern of distribution based on quantitative and dispersion indices. No less than 16 accessions of NBWR were identified based on their special traits, viz. panicle type, pericarp colour, presence or absence of awn, seed type and degree of grain shattering. The NBWR accessions exhibited a combination of morphological traits from open panicle, grain with awns, red pericarp, short grain type, and degrees of grain shattering. Others mimic commercial rices with close panicle, awnless grains, white pericarp, long or short grain-type. Invariably, the NBWRs mimic and stand as tall as cultivated rice namely MR219, MR220, or MR235 and these NBWR accessions stand among equals morphologically vis-a-vis the commercial rice varieties. Most accessions displayed varying degrees of grain shattering in excess of 50%, except Acc9 and Acc12. The seasonal dynamics of on the prevalence of dominant NBWR accessions were also displaying significant differences among farm blocks. While Bagan Terap farm block, for example, did not record any measurable changes in the dominant NBWR accessions over seasons, the Sungai Leman farm block recorded measurable season-mediated changes in the dominant NBWR accessions. Sungai Leman started with NBWR Acc3, Acc4, Acc5, Acc7, Acc8, and Acc12 in season 1 of 2006/2007, but no measurable records of Acc3 and Acc5 were shown in season 2 of 2007. In season 3 of 2007/2008, only Acc8 and Acc12 prevailed in the farm block. In Sawah Sempadan farm block, season 3 of 2007/2008 showed much reduced prevalence of NBWRs leaving only Acc8 and Acc12. Most accessions registered clump or under-dispersed spatial distribution pattern based on quantitative indices: variance-to-mean ratio (VMR) and Lloyd's patchiness values. The dynamics on the extent of infestation and prevalence of dominant NBWR accessions registered both season- and farm-block mediated differences. Most accessions showed VMR >1 thus indicative of having a clump or clustered spatial distribution, as exemplified by Acc3, Acc4, Acc7, Acc8 and Acc12 in all farm blocks throughout three seasons. Some accessions have either random or uniform distribution in a few farm blocks. The Acc8 has the highest population counts based on important value index, followed by Acc12, and both were the most dominant accession while Sawah Sempadan was the worst farm block infested by NBWR compared to other farm blocks. These results were discussed in relation with the current agronomic and weed management practices, water availability and extension services in the granary.

Development of Expert System for Water Quality Parameter Estimation Using Avenue (Avenue를 활용한 수질매개변수 추정 전문가 시스템 개발)

  • Bae, Duk-Hyo;Han, Gun-Yeon;Choi, Chul-Gwan
    • Journal of Korea Water Resources Association
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    • v.35 no.2
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    • pp.161-171
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    • 2002
  • It has been known that the accurate estimates of 2-dimensional water quality model parameters are difficult for non-experts due to the complexity of theoretical background and input requirement and complicated inter-relationship between model Parameters. The main goal of this study is to Provide expert system for the optimal estimation of water quality model parameters, which is based on the development of chaining mechanism according to the sensitivity analysis of model parameter interactions and GUI interface system on ArcView Avenue. The selected study area is the 35.3- km main Han river starting from Paldang Dam site to the Point of Indo bridge and the tributary inflows including pollutant data are used for the system application and validation. The estimated main model parameters are 0.367 for transverse dispersion coefficient, 0.074 for and 0.162 for. It also shows that the simulated water quality constituents such as DO and BOD based on the estimated model parameters are well agreed with the observed ones. It can be concluded that the developed GIS-based expert system for water quality model parameter estimation and graphical representation of water quality analysis is useful for the scientific water quality management.

Development of Response Scenario for a Simulated HNS Spill Incident (위험유해물질 유출사고 대응을 위한 가상시나리오 개발)

  • Lee, Moonjin;Oh, Sangwoo
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.20 no.6
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    • pp.677-684
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    • 2014
  • In response to possible HNS (Hazardous and Noxious Substance) spill accident, HNS spill accident scenario and response scenario were developed. The accident area listed in scenarios is the coastal area of Busan, and scenario for possible accident in the designated area and strategies to respond the accident were developed, respectively. The scenario for accident was developed by designating HNS spill according to risk evaluation of HNS and analysis of HNS spill probability along the coastal area of Busan, and then estimating possible and potential impact from the accident. The scenario for response has been suggested as a systematical responding operations in order to effectively reduce the estimated impact from the accident. The possible HNS spill accident on the seas around Busan, has been designated by the spillage of 1,000ton of xylene due to collision accident in Gamcheon Port, and the possible impacts occurred by the accident has been simulated with the help of the atmospheric and oceanic dispersion model of xylene. In the responding scenario for the accident, a phased strategies regarding emergency rescue of peoples, protection and recovery of xylene, protective measures for the responders, and post management of the accident have been suggested.

The Effects of Supplementary Education Awareness on Interpersonal Communication for Health Care Providers (종합병원 의료인의 교육훈련 인식이 의료인 상호간 커뮤니케이션에 미치는 영향)

  • Jung, Sang-Jin
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.11
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    • pp.411-420
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    • 2018
  • This study was conducted to identify the effects of interpersonal communication between health care providers after receiving supplementary education. The participants of this study were 433 health care providers who work at 29 general hospitals in Gwangju Metropolitan City and Jeollanamdo Province. Data were collected from June 8 to June 25, 2018 and evaluated by t-tests, dispersion analysis, correlation analysis and stepwise regression. The results were produced by investigating interpersonal communications according to socio-demographic and health-related characteristics including age, education level, bed size of the hospital at which the participant worked, job satisfaction, hospital location, personal health status, experience with health care management and experience with depression. There were significant differences in communication observed according to supplemental education awareness regarding age, bed size of hospital, occupation, wage, type of medical institution of employment, job satisfaction, work location, health status, health care education experience and chronic disease. There were positive correlations between supplemental education awareness in health workers and their interpersonal communication. The factors that had positive effects on interpersonal communication were level of education and health-related education experience, while age, hospital bed size and job dissatisfaction had negative effects. Finally, support environment, learning transfer and results were identified as sub-factors of supplemental education. Based on the results above, it was proposed that educational training to enhance results, provide a supportive environment and foster learning transfer be developed to increase communication between health workers and provide a safe health service for patients.

Spatial Distribution Patterns and Population Structure of Doellingeria scabra at Mt. Maebong in Korea (한국 매봉산 참취의 공간적 분포 양상과 집단 구조)

  • Lee, Byeong Ryong;Huh, Man Kyu
    • Journal of Life Science
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    • v.29 no.7
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    • pp.762-768
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    • 2019
  • Doellingeria scabra Thunb. (syn. Aster scaber Thunb.), a perennial herb in the family Asteraceae, is frequently found in the wild mountain regions of Korea. This aim of this work was to measure the characteristics of patchiness of D. scabra in a local population on Mt. Maebong in Taeback-ci, Gangwon-do. The spatial distribution pattern of this species was estimated by analyzing ecological data by methods including the index of dispersion, Lloyd's mean crowding, and Morisita's index. The mean population density of the D. scabra population was 2.94. The D. scabra individuals were uniformly or randomly distributed in small-scale plots and were aggregately distributed in two large-scale plots ($16{\times}32m^2$ and $32{\times}32m^2$). The mean crowding ($M^*$) was 0.916. The mean patchiness index (PAI) was 0.796. Morisita's coefficient tended to decrease the density of the population as the plot size increased. The expected value of Eberhardt's index ($I_E$) in the local population was 2.623. Moran's I of D. scabra significantly differed from the expected value in 6 of 8 cases (75.0%). The first five classes were positive, with four showing statistical significance, indicating similarity among individuals in the first four distance classes (I-IV, 8 m), The results presented here could provide a theoretical basis for the conservation of D. scabra (Korean: chamchwi) and for the rehabilitation and sustainable management of forest ecosystems on Mt. Maebong, as well as on other mountains.

A Study on the Status and Performance of Cultural Heritage in the Demilitarized Zone on the Korean Peninsula (한반도 비무장지대 문화유산의 실태조사 현황과 성과 고찰)

  • HWANGBO Kyung
    • Korean Journal of Heritage: History & Science
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    • v.57 no.2
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    • pp.28-50
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    • 2024
  • A fact-finding survey of the Demilitarized Zone can be said to be a very meaningful academic survey linked to previous index surveys of protected military areas and municipal and excavation surveys of ruins and military sites on Mount Dora. Not a few ruins were first discovered in this survey, and the locations, structures, and restoration artifacts of the previously investigated ruins were confirmed differently, raising the need for a detailed investigation. In particular, it is noteworthy that various relics from the Paleolithic Age to the Joseon Dynasty were recovered from relics dispersion sites such as Josan-ri and Cheorwon Gangseo-ri in Paju, and Hoengsan-ri Temple Site is also a Buddhist relic in the Demilitarized Zone. However, in the case of some graveyards and relics sites in the Paju region, it was an opportunity to understand the reality that they are not safe from cultivation and development, and the ruins of Cheorwon Capital Castle, Seongsanseong Fortress, Jorangjin Bastion, and Gangseo-ri Bastion were damaged during the construction of military facilities, and an urgent investigation is needed. Also, farmland and hilly areas around the ruins of Jangdan, Gunnae-myeon, and Gangsan-ri have not been properly investigated for buried cultural assets due to small-scale development. Therefore, it is an important time for the relevant authorities and agencies to cooperate more closely to establish special management and medium- to long-term investigation measures for the cultural heritage in the Demilitarized Zone based on the results of this fact-finding investigation.