• 한국산업융합학회 논문집
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• 제20권2호
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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.

• 대한의용생체공학회:의공학회지
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• 제24권6호
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• pp.481-486
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• 2003

본 논문에서는 의료 영상 분야의 국제 표준인 DICOM을 툴킷 형태로 구현한 소프트웨어에 대하여 기술한다. 기존의 툴킷들은 영상 관련 기능들을 별도로 구현해야 하거나 유닉스 운영체제를 기반으로 개발된 후에 윈도우즈 운영체제오 이식되거나 속도나 메모리 관리 측면이 배제되었거나 DICOM의 방대함에 기인하여 매우 복잡한 구조로 되어있는 단점을 가지고 있다. 제안된 툴킷은 기존 툴킷들의 단점을 보완하고 DICOM이 주로 사용되는 병원의 환경에 적합하도록 설계하였다. 즉, 윈도우 운영체제를 사용하는 일반 PC에서 대용량의 영상을 조회한 수 있도록 하였으며 다중 자업을 지원하여 자업 처리 속도 및 편리성을 증가시켰고 임상에서 필요한 대부분의 기능을 제공하며 객체 지향적 구조로 설계되어 사용자가 짧은 기 간 내에 개발 할 수 있도록 하였다. 실험 결과 제안된 툴킷을 이용하여 일반 PC 환경에서 CT 50장, MR 50장, CR 10장, DX 10장의 DICOM 영상을 12초 이내에 출력하며 소량의 물리적 메모리만을 소모하는 성능을 보였다.

• 비교교육연구
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• 제28권4호
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• pp.51-82
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• 2018

이 연구는 오늘날 학교교육에서 평가관을 지배하고 있는 표준화시험에 대해 미국의 사례를 중심으로 그 역사적 전개과정에 대해 고찰하고 시사점을 논한다. 특히 20세기 초 과학주의의 확산과 함께 표준화시험이 학교교육의 개선을 위해 적용되는 과정에서 카네기재단이 행한 매개적 역할에 주목하고 있다. 20세기 이래 표준화시험은 미국교육에서 중요한 지위를 지니고 있으며, 지식, 학력, 책무성을 강조하는 본질주의적 교육관을 대표하고 있어, 아동중심성, 경험, 민주주의 등을 강조하는 진보주의적 교육관과 대치되기도 한다. 표준화시험을 중심으로 한 미국교육의 전개과정에 대한 이해는 2000년대 이후 학력평가가 국제적으로 강화되고 있는 흐름에 대한 분석의 기초로서 중요하다.

• 한국기록관리학회지
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• 제17권3호
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• pp.1-21
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• 2017

구술사는 살아있는 사람의 이야기를 통해서 이루어진다. 구술사를 통해서 수집된 자료는 단순한 사실이나 정보의 덩어리가 아니라, 구술자의 인격을 온전하게 드러내는 사람 그 자체이다. 이런 까닭에 구술사연구와 자료 수집 및 활용은 엄격한 윤리적인 기준에 입각해서 이루어질 필요가 있다. "생명윤리법"은 인간대상연구에 대해서 비슷한 관점을 공유하면서, 기관생명윤리위원회의 심의와 관리 대상으로 구술사를 포함하고 있다. 그렇지만 "생명윤리법"의 인격과 권리 보호는 생명과학연구를 중심으로 작성된 것으로, 사람을 상대로 가치 지향적이고, 비판적인 접근이 이루어지는 구술사를 비롯한 질적 연구에 합당하지 않다. 이 연구에서는 "생명윤리법"의 인간대상연구와 관련된 규정의 상세한 내용을 알아보고, 그것이 구술사와 같은 인문사회과학연구에 적용될 때에 나타날 수 있는 문제점을 점검하였다. 이러한 과정들을 통하여 구술사 연구가 학문적 독자성과 자율성을 유지하면서 지속가능할 수 있는 방법적인 대안들을 제시하였다.

• 암석학회지
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• 제3권1호
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• pp.41-48
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• 1994

암석의 용해 방법에 따른 미량원소 분석결과를 비교해 보기 위해 미국 지질조사소의 암석 표준시료 3종류 (G-2, W-2, BHVO-1)를 비이커-가열판법, 마이크로파 오븐법, 알칼리 용융법으로 용해 시켜 유도결합 플라즈마 질량분석기를 사용, 각각의 미량원소 농도를 측정하여 용해 방법에 따른 차이를 살펴보았다. 전체적으로 보아 비이커-가열판법으로 용해시킨 경우와 마이크로파 오븐법으로 용해시킨 경우는 비슷한 분석결과를 보인다. 알칼리 용융법을 사용하여 용해시킨 경우 높은 온도 때문에 Pb, Cu, Rb 등의 휘발성 원소 상당 부분이 손실된다. 산분해법의 경우 Zr, Hf 등의 원소가 저어콘 등의 불용성 광물에 농집되어 있을 때에는 광물들의 불충분한 용해로 인해 측정 농동가 낮게 나타난다. 회토류 원소 분석결과는 시료 용해 방법 사이에 차이가 없었으며 추천치와 대체로 일치하였으나 알칼리 용융법의 경우 큰 희석인자로 인한 측정상의 문제점이 일부 있었다.

• Journal of the Optical Society of Korea
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• 제12권4호
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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.

• 약학회지
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• 제48권3호
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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.

• 한국지하수토양환경학회지:지하수토양환경
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• 제18권5호
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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.

• 한국중재학회지:중재연구
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• 제31권1호
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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.

• Journal of Ginseng Research
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• 제43권1호
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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.