• Title/Summary/Keyword: Four-component

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Development of Primary Reference Gas Mixtures for Liquid Propane (혼합 액체 프로판 표준가스 개발)

  • Jeong, Yun-sung;Kim, Jin-seog;Bae, Hyun-kil;Kang, Ji-hwan;Lee, Seung-ho;Kim, Yong-doo
    • Journal of the Korean Institute of Gas
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    • v.25 no.4
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    • pp.49-56
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    • 2021
  • Liquefied Petroleum Gas is divided into liquefied gases containing propane (C3H8) and butane (C4H10). The quality of LPG varies greatly depending on the composition of the mixture, so it is important to measure the composition accurately. It is difficult to determine the composition of the mixture because liquid and gas coexist at room temperature. Therefore, the uncertainty in determining the concentration of hydrocarbons by component is high, and there are many problems that differ from the actual content standard. Therefore, it is necessary to develop a mixed liquid propane standard gas for the composition and accurate concentration of hydrocarbon substances. Mixed liquid propane standard gas is manufactured into bellows-type constant-pressure cylinders by ISO-6142 (2015). The homogeneity of the four standard gases manufactured was confirmed to be GC-FID. The manufacturer's uncertainty of expansion was 0.01 % to 0.30 % and homogeneity was 0.03 % to 0.25 %. In this mixed liquid propane standard gas, the relative expansion uncertainty of weight method, manufacturing consistency, cylinder adsorption and long-term stability was developed within 0.26 %-1.3 9% (95% of confidence level, k=2).

Topographic Variability during Typhoon Events in Udo Rhodoliths Beach, Jeju Island, South Korea (제주 우도 홍조단괴해빈의 태풍 시기 지형변화)

  • Yoon, Woo-Seok;Yoon, Seok-Hoon;Moon, Jae-Hong;Hong, Ji-Seok
    • Ocean and Polar Research
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    • v.43 no.4
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    • pp.307-320
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    • 2021
  • Udo Rhodolith Beach is a small-scale, mixed sand-and-gravel beach embayed on the N-S trending rocky coast of Udo, Jeju Island, South Korea. This study analyzes the short-term topographic changes of the beach during the extreme storm conditions of four typhoons from 2016 to 2020: Chaba (2016), Soulik (2018), Lingling (2019), and Maysak (2020). The analysis uses the topographic data of terrestrial LiDAR scanning and drone photogrammetry, aided by weather and oceanographic datasets of wind, wave, current and tide. The analysis suggests two contrasting features of alongshore topographic change depending on the typhoon pathway, although the intensity and duration of the storm conditions differed in each case. During the Soulik and Lingling events, which moved northward following the western sea of the Jeju Island, the northern part of the beach accreted while the southern part eroded. In contrast, the Chaba and Maysak events passed over the eastern sea of Jeju Island. The central part of the beach was then significantly eroded while sediments accumulated mainly at the northern and southern ends of the beach. Based on the wave and current measurements in the nearshore zone and computer simulations of the wave field, it was inferred that the observed topographic change of the beach after the storm events is related to the directions of the wind-driven current and wave propagation in the nearshore zone. The dominant direction of water movement was southeastward and northeastward when the typhoon pathway lay to the east or west of Jeju Island, respectively. As these enhanced waves and currents approached obliquely to the N-S trending coastline, the beach sediments were reworked and transported southward or northward mainly by longshore currents, which likely acts as a major control mechanism regarding alongshore topographic change with respect to Udo Rhodolith Beach. In contrast to the topographic change, the subaerial volume of the beach overall increased after all storms except for Maysak. The volume increase was attributed to the enhanced transport of onshore sediment under the combined effect of storm-induced long periodic waves and a strong residual component of the near-bottom current. In the Maysak event, the raised sea level during the spring tide probably enhanced the backshore erosion by storm waves, eventually causing sediment loss to the inland area.

A study of the selection criteria for Localization of Military Weapon (무기체계 국산화 대상 선정기준 연구)

  • RYU, SEOKBEOM
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.4
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    • pp.338-344
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    • 2021
  • Elements that threaten domestic security, such as diplomatic changes in the four major powers surrounding the Korean Peninsula and restrictions on supply and demand of parts due to COVID-19, are constantly increasing. The importance of localizing weapon systems has grown to respond proactively to the threat. As localization is not conducted evenly by the field, it is necessary to change the criteria for selecting localization targets. Establishing standards for selecting targets is difficult due to a lack of research to identify targets. This paper emphasized that the smooth supply of parts from overseas should be examined to identify targets for localization. If suppliers are not distributed evenly in the market, there is a risk of potential supply problems. CRk and HHI, representing the market structure, were proposed as indicators for evaluating the degree of smoothness quantitatively. Among them, CRk is used in Korea to check the market concentration, but there is a limit in the subjectivity of the evaluator, so it cannot be applied without a separate study on the market structure. Therefore, HHI should be applied.

Bangladesh Employees Organizational Commitment and Antecedents (방글라데시 근로자의 조직몰입과 선행변수)

  • Kim, Boine
    • International Area Studies Review
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    • v.18 no.3
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    • pp.131-145
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    • 2014
  • Abundance of low-wage labor resources, strategic location connecting East-West Asia and business professionals are fluent in English are strength of Bangladesh. Also the business environment changes in China such as the wage increases and labor regulations enhancement acts as searching for replacement of investment where Bangladesh is considered as substitute. At this point there is a need for research of Bangladesh employees at human resource management level. Therefore this study focus on the research of an important component of human resource management, organizational commitment. This study analysis the Bangladesh employees organizational commitment and its antecedent. This study consider four antecedents, role ambiguity, role conflict, voluntary participation and the work centrality and three organizational commitment, affective organizational commitment, continuous organizational commitment and normative organizational commitment. As results show, role ambiguity and role conflict has a negative influence on affective organizational commitment. And voluntary participation and work centrality give positive influence. Role ambiguity showed a negative effect on continuous organizational commitment, however role conflict show positive effect. Voluntary participation and work centrality showed positive effect on normative organizational commitment and role ambiguity showed negative influence. Results of this study give clue to understand Bangladesh employees organizational commitment and its relation among variables. And thus the need for appropriate management presented.

The properties of glass ceramics of Li2O-Al2O3-SiO2 system according to nucleation agent (조핵제 원료에 따른 Li2O-Al2O3-SiO2계 결정화 유리 특성)

  • Park, Hyun-Wook;Lee, Ji-Sun;Lim, Tae-Young;Hwang, Jonghee;Ra, Yong-Ho;Noh, Myoung-Rae;Seo, Kwan-Hee;Kim, Jin-Ho
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.28 no.6
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    • pp.229-234
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    • 2018
  • The glass-ceramic of $Li_2O-Al_2O_3-SiO_2$ system was synthesized by using $ZrO_2$, $ZrSiO_4$, $ZrOCl_2$ and $Zr(SO_4)_2$, which is a raw material of Zr serving as a nucleation agent. It was confirmed that Avrami parameter of these four glasses is over 3 for bulk crystallization. The glass synthesized by $ZrOCl_2$, and $Zr(SO_4)_2$ showed high melting quality during the melting process. It is also observed that the Zr component is uniformly distributed in the glass. Various characterizations was evaluated, including composition analysis and bending strength.

Physicochemical and sensory characteristics of commercial RTD cold brew coffees (RTD (Ready-to-drink) 콜드브루커피의 이화학 및 감각특성 분석)

  • Song, Young-Ju;Hwang, Hyun-Ju;Lee, Seung-Joo
    • Korean Journal of Food Science and Technology
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    • v.51 no.1
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    • pp.35-41
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    • 2019
  • The sensory characteristics of eight commercial ready-to-drink (RTD) cold brew coffees were compared by descriptive analysis. The cold brew coffee samples were analyzed for hunter color values, brown color, turbidity, pH, titratable acidity, soluble solids, total phenolic content, and chlorogenic acid content. Three appearances, nine aroma, five flavor/taste, and four texture/mouth-feel related sensory attributes were evaluated by a panel of nine judges. The results of three-way analysis of variance of descriptive data showed that all sensory attributes except "fruit" aroma, "dark chocolate" aroma, "bitter" aroma, and "sweet" taste had significant differences among the samples (p<0.05). Based on the principal component analysis (PCA) of the descriptive data, the samples were primarily separated by first and second principal components, which accounted for 81.78% of the total variance among the samples with high intensities of "nutty aroma", "grain aroma", and "grain taste" versus "earth aroma", "sour aroma", "sour taste", "astringent", "smoothness", and "residual". In the correlation analysis of sensory terms and physicochemical parameters, titratable acidity and soluble solids showed significant positive correlations with earth aroma and smoothness characteristics.

Assessment of Water Quality in the Miho Stream Using Multivariate Statistics (다변량 통계기법을 이용한 미호천 본류 수질특성 평가)

  • Yoon, Hyeyoung;Kim, Jeehyun;Chae, Minhee;Cho, Yoonhae;Cheon, Seuk
    • Journal of Environmental Impact Assessment
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    • v.28 no.4
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    • pp.373-386
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    • 2019
  • In The study, is to investigate the spatial characteristics of the Miho stream, which is the main tributary of the Geum River system, and to identify the main factors influencing the water quality using water quality analysis and multivariate analysis. The survey subjects were selected as 7 main sites in the Miho stream water system, From 2012 to 2017, 16 items including weather temperature and weather data were used for multivariate analysis. As a result of the water quality analysis, the average concentration of BOD and COD for 6 years was 3grade (normal) compared with the water quality environmental standard (river) of conditions. The concentrations of nitrogen and phosphorus were highest at th upstream site, then decreased and then increased again by the hydrogeological and geomorphological effect. Cluster analysis of spatial and water quality characteristics, it was evaluated as three clusters and the pollution sources is the greatest impact. As a result of principal component analysis and factor analysis on each cluster and mainstream, three to four major components were extracted. Main stream and the Cluster 1, Cluster 3 first principal factor included nitrogen and seasonal factors,first factor of Cluster 2 included nitrogen and water temperature. Nitrogen is the principal factor which affects water quality in Miho stream.

Utility of a modified components separation for abdominal wall reconstruction in the liver and kidney transplant population

  • Black, Cara K;Zolper, Elizabeth G;Walters, Elliot T;Wang, Jessica;Martinez, Jesus;Tran, Andrew;Naz, Iram;Kotha, Vikas;Kim, Paul J;Sher, Sarah R;Evans, Karen K
    • Archives of Plastic Surgery
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    • v.46 no.5
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    • pp.462-469
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    • 2019
  • Background Incisional hernia is a common complication following visceral organ transplantation. Transplant patients are at increased risk of primary and recurrent hernias due to chronic immune suppression and large incisions. We conducted a retrospective review of patients with a history of liver or kidney transplantation who underwent hernia repair to analyze outcomes and hernia recurrence. Methods This is a single center, retrospective review of 19 patients who received kidney and/or liver transplantation prior to presenting with an incisional hernia from 2011 to 2017. All hernias were repaired with open component separation technique (CST) with biologic mesh underlay. Results The mean age of patients was $61.0{\pm}8.3years\;old$, with a mean body mass index of $28.4{\pm}4.8kg/m^2$, 15 males (78.9%), and four females (21.1%). There were seven kidney, 11 liver, and one combined liver and kidney transplant patients. The most common comorbidities were hypertension (16 patients, 84.2%), diabetes (9 patients, 47.4%), and tobacco use (8 patients, 42.1%). Complications occurred in six patients (31.6%) including hematoma (1/19), abscess (1/19), seroma (2/19), and hernia recurrence (3/19) at mean follow-up of $28.7{\pm}22.8months$. With the exception of two patients with incomplete follow-up, all patients healed at a median time of 27 days. Conclusions This small, retrospective series of complex open CST in transplant patients shows acceptable rates of long-term hernia recurrence and healing. By using a multidisciplinary approach for abdominal wall reconstruction, we believe that modified open CST with biologic mesh is a safe and effective technique in the transplant population with complex abdominal hernias.

A Study on Open Source Transition Strategy of Record System (기록시스템의 오픈소스화 전략 연구)

  • An, Dae-jin;Yim, Jin-hee
    • The Korean Journal of Archival Studies
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    • no.52
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    • pp.119-170
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    • 2017
  • This study aims to analyze the environment for the open-source records system and to identify the risk and requirements for the success of the strategy in Korea. For this, Chapter 2 presented a review of the strategic benefits of open source to public organizations, developers, and users. It also discussed the process of cooperatively developing and releasing the source code and the technology infrastructure supporting open source. In Chapter 3, six representative open-source projects in the field of records management were selected, and case studies were conducted. To derive comprehensive implications, we have divided the main development body of open-source projects into international organizations, international cooperation systems, national archives, and software development companies. We also analyzed the background and purpose of each project, the agents of development and funding, the governance model, the development period and cost, the business model and software architecture, the community composition, and the licensing strategy. Through this, we have derived four critical success factors. In terms of technology, a component-based design was required; therefore, we proposed a microservice architecture and a model-view-controller design pattern. Next, it was necessary to reestablish system requirements of records center and archives. Moreover, we also proposed a dual licensing strategy to allow developers to easily participate in open-source projects. Lastly, we emphasized a strong governance structure and an effective cooperation framework to create a sustainable community. For a record system to be open-source successfully in an organization-centered market, the roles of software developers and end users should be exercised more in the community. To achieve this, it is important to build various collaborative tools and development infrastructure from a planning stage to a centralized one.

Bioactive lipids in gintonin-enriched fraction from ginseng

  • Cho, Hee-Jung;Choi, Sun-Hye;Kim, Hyeon-Joong;Lee, Byung-Hwan;Rhim, Hyewon;Kim, Hyoung-Chun;Hwang, Sung-Hee;Nah, Seung-Yeol
    • Journal of Ginseng Research
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    • v.43 no.2
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    • pp.209-217
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    • 2019
  • Background: Ginseng is a traditional herbal medicine for human health. Ginseng contains a bioactive ligand named gintonin. The active ingredient of gintonin is lysophosphatidic acid C18:2 (LPA C18:2). We previously developed a method for gintonin-enriched fraction (GEF) preparation to mass-produce gintonin from ginseng. However, previous studies did not show the presence of other bioactive lipids besides LPAs. The aim of this study was to quantify the fatty acids, lysophospholipids (LPLs), and phospholipids (PLs) besides LPAs in GEF. Methods: We prepared GEF from white ginseng. We used gas chromatography-mass spectrometry for fatty acid analysis and liquid chromatography-tandem mass spectrometry for PL analysis, and quantified the fatty acids, LPLs, and PLs in GEF using respective standards. We examined the effect of GEF on insulin secretion in INS-1 cells. Results: GEF contains about 7.5% linoleic (C18:2), 2.8% palmitic (C16:0), and 1.5% oleic acids (C18:1). GEF contains about 0.2% LPA C18:2, 0.06% LPA C16:0, and 0.02% LPA C18:1. GEF contains 0.08% lysophosphatidylcholine, 0.03% lysophosphatidylethanolamine, and 0.13% lysophosphatidylinositols. GEF also contains about 1% phosphatidic acid (PA) 16:0-18:2, 0.5% PA 18:2-18:2, and 0.2% PA 16:0-18:1. GEFmediated insulin secretion was not blocked by LPA receptor antagonist. Conclusion: We determined four characteristics of GEF through lipid analysis and insulin secretion. First, GEF contains a large amount of linoleic acid (C18:2), PA 16:0-18:2, and LPA C18:2 compared with other lipids. Second, the main fatty acid component of LPLs and PLs is linoleic acid (C18:2). Third, GEF stimulates insulin secretion not through LPA receptors. Finally, GEF contains bioactive lipids besides LPAs.