• Title/Summary/Keyword: Mass standards

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A Study on Combustion and Exhaust Emission in Direct Injection Diesel Engine (직접분사식 디젤기관의 연소 및 배기에 관한 연구)

  • Kim, Du-Beom;Kim, Gi-Bok;Kim, Chi-Won;Han, Sung-Hyun
    • Journal of the Korean Society of Industry Convergence
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    • v.20 no.2
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    • pp.105-113
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    • 2017
  • Recently the direct injection diesel engine is the most efficient one available for road vehicles, so this fundamental advantage suggests the compression injection diesel engine are a wise choice for future development efforts. The compression ignition diesel engine, with its bigger compression ratios if compared to the SI engine, offers a higher thermodynamic efficiency, also additionally the diesel engine with its less pumping losses due to the throttled intake charge as in a SI engine has higher fuel economy. But the largest obstacle to the success of this engine is meeting emission standards for Nitric oxides and particulate matter while maintain fuel consumption advantage over currently available engines. Thus its use should be largely promoted, however, diesel engine emits more Nitric oxides and particulate matter than other competing one. There has been a trade-off between PM and NOx, so efforts to reduce NOx have increased PM and vice versa, but trap change this situation and better possibility emerge for treating NOx emission with engine related means, such as injection timing, equivalence ratio, charge composition, and engine speed. The common rail direct injection system is able to adjust the fuel injection timing in a compression ignition engine, so this electronically controlled injection system can reduce the formation of NOx gas without increase in soot. In this study it is designed and used the engine test bed which is installed with turbocharge and intercooler. In addition to equipped using CRDI by controlling injection timing with mapping modulator, it has been tested and analyzed the engine performance, combustion characteristics, and exhaust emission as operating parameters.

A Study for the Implementation of the DICOM Toolkit Software (DICOM 툴킷 소프트웨어 구현에 관한 연구)

  • Shin Dong Kyu;Kim Dong Youn;Kim Dong Sun
    • Journal of Biomedical Engineering Research
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    • v.24 no.6 s.81
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    • pp.481-486
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    • 2003
  • This paper describes the implementation of the toolkit software for the DICOM. the international standards of medical imaging. Well known toolkits do not have the functions related to imaging or ported to Windows OS after developed at UNIX OS or do not have mechanism for the speed and memory management or have complicated structure comes from DICOMI complexity. The toolkit introduced in this paper was designed for the hospital environments. It handles mass images at Windows based PC system. supports multi-threading to enhance the efficiency. supports every functions in Object Oriented Programming style needed at clinical application which makes the rapid development of the DICOM related applications. The results says that the toolkit can display 50 CT, 50 MR, 10 CR and 10 DX images in 12 seconds and occupy small quantity of physical memory at usual PC system.

A Historical Reappraisal on the Standardized Testing in the US Education Focusing on the Role of the Carnegie Foundation for the Advancement of Teaching (미국교육에서 표준화시험의 역사적 전개와 시사점: 카네기재단의 역할)

  • Lee, Yoonmi
    • Korean Journal of Comparative Education
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    • v.28 no.4
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    • pp.51-82
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    • 2018
  • This study examines the history and current debates on the standardized testing in the United States, particularly focusing on the role that the Carnegie Foundation for the Advancement of Teaching (CFAT) played in the process. It discusses the particular history of the United States associated with the pragmatic and scientific culture, rise of mass secondary education, and the social efficiency movement as the backdrop of the expansion of standardized testing. The role of the CFAT in this movement is investigated as to the way it contributed to setting standards for American secondary and higher education through promoting standardized tests such as SAT and GRE, and by establishing the ETS, a highly influential testing agency. The underlying educational assumptions and practices in standardized testing are critically examined in light of a more personal or context-bound and social justice-oriented paradigm for educational evaluation.

Oral History Research and Human Subject Research on Bioethics and Safety Law (구술사 연구와 「생명윤리법」의 인간대상연구)

  • Lee, Hosin
    • Journal of Korean Society of Archives and Records Management
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    • v.17 no.3
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    • pp.1-21
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    • 2017
  • Oral history research is carried out through collecting information about a living person. The data collected from an oral history project is not a mere fact or a mass of information but accounts of persons who reveal their own personalities. For this reason, oral history research and data collection and the use of such data must be based on rigorous ethical standards. The Bioethics and Safety Law shares a similar view on human subject research, and the Institutional Review Boards includes human subject research as a subject of review and management. However, the Bioethics and Safety Law's protection of personalities and human rights focuses on life sciences methodologies, which are not suitable for qualitative research, such as an oral history of a value oriented and critical approach to human beings. This study examines the details of the Bioethics and Safety Law related to human subject research and the problems that may arise when this law is applied to subjects in humanities and social sciences such as oral history. Through this study, alternative methodologies, which can be used for oral history research, while maintaining academic autonomy, are suggested.

암석 용해방법에 따른 미량원소 분석결과 비교

  • 최만식;정창식;박계헌
    • The Journal of the Petrological Society of Korea
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    • v.3 no.1
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    • pp.41-48
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    • 1994
  • Three USGS rock standards (G-2, W-2, and BHVO-1) are decomposed by three different methods, such as open beaker, microwave oven, and alkali fusion method, to compare the effect of decomposition methods for trace elememt analysis in the rock samples. Solubilized trace elements are measured with inductively coupled plasma mass spectrometer (ICP-MS). Generally the analytical results of trace elements between open beaker and microwave digestion method are not different. In case of alkali fusion method, some volatile elements such as Pb, Cu, and Rb are considerably lost. Using acid digestion method, Zr and Hf concentrations are lowered in case that these elements are concentrated in refractory minerals. The concentrations of rare earth elements are generally consistent with the recommended values, but due to large dilution factor, there are some analytical problems in alkali fusion method.

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Optical Design of A Compact Imaging Spectrometer for STSAT3

  • Lee, Jun-Ho;Jang, Tae-Seong;Yang, Ho-Soon;Rhee, Seung-Wu
    • Journal of the Optical Society of Korea
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    • v.12 no.4
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    • pp.262-268
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    • 2008
  • A compact imaging spectrometer (COMIS) for use in the STSAT3 microsatellite is currently under development. It is scheduled to be launched into a low Sun-synchronous Earth orbit (${\sim}700km$) by the end of 2010. COMIS was inspired by the success of CHRIS, which is a small hyperspectral imager developed for the ESA microsatellite PROBA. COMIS is designed to achieve nearly equivalent imaging capabilities of CHRIS in a smaller (65 mm diameter and 4.3 kg mass) and mechanically superior (in terms of alignment and robustness) package. Its main operational goal will be the imaging of Earth's surface and atmosphere with ground sampling distances of ${\sim}30m$ at the $18{\sim}62$ spectral bands ($4.0{\sim}1.05{\mu}m$). This imaging will be used for environmental monitoring, such as the in-land water quality monitoring of Paldang Lake, which is located next to Seoul, South Korea. The optics of COMIS consists of two parts: imaging telescope and dispersing relay optics. The imaging telescope, which operates at an f-ratio of 4.6, forms an image (of Earth's surface or atmosphere) onto an intermediate image plane. The dispersion relay optics disperses the image and relay it onto a CCD plane. All COMIS lenses and mirrors are spherical and are made from used silica exclusively. In addition, the optics is designed such that the optical axis of the dispersed image is parallel to the optical axis of the telescope. Previous efforts focused on manufacturing ease, alignment, assembly, testing, and improved robustness in space environments.

Analysis of $\triangle^9$-Tetrahydrocannabinol and 11-nor-9-carboxytetrahydrocannabinol in Hair by Gas Chromatography/Mass Spectrometry (가스크로마토그라피/질량분석기에 의한 모발중 대마성분 분석)

  • 양원경;한은영;박용훈;임미애;정희선
    • YAKHAK HOEJI
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    • v.48 no.3
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    • pp.207-212
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    • 2004
  • An analytic method was developed for the quantitation of $\Delta$$^{9}-$ tetrahydrocannabinol (THC) and 11-nor-9-carboxy THC (THC-COOH) in human hair. After hair samples were pulverized using Freezer Mill, deuterated internal standards were added and digested in 1 N NaOH at $100^{\circ}C$ water bath for 30 min. Digest solutions were extracted by 5 ml hexane:ethyl acetate (90:10) after acidification with acetic acid. The organic phase was evaporated under N 2 and derivatized by BSTFA (with 1% TMCS) at $85^{\circ}C$ for 45 min. The derivatized solution was separated on HP-5MS column ($30m{\times}0.25mm{\times}0.25mm$) and detected using EI-GC-MS with selective ion monitoring mode. The assay of calibration was ranged from 5 to 100 ng/50 mg hair ($r^2$>0.99) for THC and THC-COOH. Within and between-run precision were calculated at 6, 30, 60 ng/50 mg hair with coefficients of variation less than 11%. Within and between run accuracies at the same concentrations were$\pm$14% and $\pm$30% of target for both analytes, respectively. Absolute and relative recovery at 10 and 100 ng were 60∼91%. The method was used to detect and quantify THC and THC-COOH in cannabis abuser's hairs (N = 16) and SRM (N=5, THC 1 ng/mg, NIST). We detected THC and THC-COOH in only one hair sample. In SRM, % accuracy was 93% (range 86∼103%) and precision (% CV) was 8.14. We began to set up a quantitative analysis of THC and THC-COOH using EI-GC-MS. Continuously, we need to modify and develop this method in order to apply for identification in cannanbis users' hair.

A Study on the Removal Efficiency of Heavy Metals in Daenam Mine Agricultural Soil Using Heavy metal Properties by Physical separation (대남광산 농경지 토양 내 중금속 특성에 따른 물리적 선별 처리효율에 관한 연구)

  • ParK, Chan Oh;Hong, Dong-Ho;Lee, Jai-Young;Lee, Young Jae;Lee, Jin-Soo
    • Journal of Soil and Groundwater Environment
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    • v.18 no.5
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    • pp.46-55
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    • 2013
  • The main objective was to evaluate the efficiencies of different separation techniques, such as gravity separation, magnetic separation, and aerial separation. Zinc and cadmium removal efficiencies by gravity separation and magnetic separation were 28.3~29.3% and 19.1%, respectively, and were higher than the efficiency obtained by aerial separation. Results showed that the combination of gravity separation and magnetic separation in series which was to maximize the removal efficiencies gave removal efficiency of 21.5~38.7% for zinc and 22.1~23.4% for cadmium. The mass of soil meeting the regulation standards for zinc and cadmium after retrieval from the combined separation process accounted for approximately 80% of the treated soil that would be reusable without the pre-treatment procedure as the neutralization process using in the soil washing method. Physical separation techniques utilizing heavy metal properties are the alternative method to remediate heavy-metal contaminated soils in environmental and economic aspects.

Review of U.S. Courts' Procedural and Substantive Unconscionability Doctrine Regarding Mandatory Arbitration Agreement in the Nursing Home Contracts (미국 요양원 입소계약상의 강제적 중재 조항에 관한 미국 법원의 절차적, 실체적 비양심성 법리 고찰)

  • Shin, Seungnam
    • Journal of Arbitration Studies
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    • v.31 no.1
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    • pp.83-105
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    • 2021
  • If aggrieving consumers or employees cannot prove both substantive and procedural unconscionability, many U.S. state courts will enforce arbitration agreements. Additionally, U.S. courts weigh a variety of factors to determine whether an arbitration agreement is substantively unconscionable. For example, U.S. courts have considered one or a combination of the following factors: (1) the fairness of contractual terms; (2) the severity of contractual terms' deviation from prevailing standards, customs, or practices within a particular industry; (3) the reasonableness of goods-and-services contract prices; (4) the commercial reasonableness of the contract terms; (5) the purpose and effect of the terms and (6) "the allocation of risks between the parties." Further, procedural unconscionability characterized by surprise or lack of knowledge focuses on terms that are deceptively hidden in a mass of contract language, the object of another concealment, or imposed in the circumstances involving haste or high-pressure tactics so that they are not likely to be read or understood. This unconscionability doctrine can be applied to a situation where an alcoholic dementia-afflicted older adult is admitted to a nursing home. At that time, because she had alcoholic dementia, which precluded her reading, comprehending, writing, negotiating, or signing of any legal document, her son, who did not understand the adhesion contract, signed the standardized residential contract and the arbitration agreement.

Multicomponent assessment and ginsenoside conversions of Panax quinquefolium L. roots before and after steaming by HPLC-MSn

  • Huang, Xin;Liu, Yan;Zhang, Yong;Li, Shuai-Ping;Yue, Hao;Chen, Chang-Bao;Liu, Shu-Ying
    • Journal of Ginseng Research
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    • v.43 no.1
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    • pp.27-37
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    • 2019
  • Background: The structural conversions in ginsenosides induced by steaming or heating or acidic condition could improve red ginseng bioactivities significantly. In this paper, the chemical transformations of red American ginseng from fresh Panax quinquefolium L. under steaming were investigated, and the possible mechanisms were discussed. Methods: A method with reversed-phase high-performance liquid chromatography coupled with linear ion trap mass spectrometry ($HPLC-MS^n$)-equipped electrospray ionization ion source was developed for structural analysis and quantitation of ginsenosides in dried and red American ginseng. Results: In total, 59 ginsenosides of protopanaxadiol, protopanaxatriol, oleanane, and ocotillol types were identified in American ginseng before and after steaming process by matching the molecular weight and/or comparing $MS^n$ fragmentation with that of standards and/or known published compounds, and some of them were determined to be disappeared or newly generated under different steaming time and temperature. The specific fragments of each aglycone-type ginsenosides were determined as well as aglycone hydrated and dehydrated ones. The mechanisms were deduced as hydrolysis, hydration, dehydration, and isomerization of neutral and acidic ginsenosides. Furthermore, the relative peak areas of detected compounds were calculated based on peak areas ratio. Conclusion: The multicomponent assessment of American ginseng was conducted by $HPLC-MS^n$. The result is expected to provide possibility for holistic evaluation of the processing procedures of red American ginseng and a scientific basis for the usage of American ginseng in prescription.