• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 춘계학술대회 논문집 센서 박막재료 반도체 세라믹
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• pp.208-212
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• 2003

Silicon transient voltage suppressors (TVSs) are clamping devices that limit voltage spikes by low impedance avalanche breakdown of a rugged silicon PN junction. They are used to protect sensitive components from electrical overstress such as that caused by induces lightning, inductive load switching and electrostatic discharge. In this paper, we present static and dynamic characteristics of TVS diode using thermal analysis simulation software. And also, it is presented that the thermal dissipation characteristics of TVS diode in the transient state.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2015년도 전력전자학술대회 논문집
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• pp.487-488
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• 2015

New inverter motor drive systems consume 30%~50% less energy compared to existing motor drive systems. For inverter motor drive systems, the development of a 1200V high side driver is critical. This paper presents an advanced 1200V high side driver with low power consumption and high ruggedness. This solution implements a high voltage level shifter which consumes low power by adding a clamped VGS LDMOS driver to the conventional short pulse generator. Moreover, this paper proposes a highly rugged 1200V LDMOS which improves SOA by limiting the hole current. This paper could be applied to smart power modules used for HVAC (heating, ventilation, and airconditioning) and industrial inverters. Consequently, this paper will provide design engineers with an understanding of how they can make a significant contribution to worldwide energy savings.

• 대한원격탐사학회지
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• 제4권1호
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• pp.49-60
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• 1988

Principal Component Analysis (PCA) was applied for regional geological mapping to a multivariate data set of the Landsat TM data in the heavily vegetated and topographically rugged Chungju area. The multivariate data set selection was made by statistical analysis based on the magnitude of regression of squares in multiple regression, and it includes R1/2/R3/4, R2/3, R5/7/R4/3, R1/2, R3/4. R4/3. AND R4/5. As a result of application of PCA, some of later principal components (in this study PC 3 and PC 5) are geologically more significant than earlier major components, PC 1 and PC 2 herein. The earlier two major components which comprise 96% of the total information of the data set, mainly represent reflectance of vegetation and topographic effects, while though the rest represent 3% of the total information which statistically indicates the information unstable, geological significance of PC3 and PC5 in the study implies that application of the technique in more favorable areas should lead to much better results.

• International journal of advanced smart convergence
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• 제8권2호
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• pp.30-38
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• 2019

Recently, the spread of personal mobility has been rapidly increasing due to the development of environmentally friendly alternative transportation means. In addition, the level of battery technology is also rapidly developing, accelerating the popularization of personal mobility. Such personal mobility has convenience of location transfer, amusement, and high portability compared to other transportation devices. Most personal mobility, however, is made up of small wheels, which cannot overcome obstacles such as rugged roads or obstacles on the road. In this paper, to solve these problems, we tried to devise a device that can easily overcome obstacles by combining wheels with small moving means. The wheel size can be mounted on the front wheel of the small moving means in a protruding manner so that obstacles can be encountered before the front wheels and the safety and ride comfort of the running can be improved.

• 한국막학회:학술대회논문집
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• 한국막학회 1997년도 제5회 하계 Workshop (97 한,카 국제공동 Workshop, 고도 수처리를 위한 막분리 공정)
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• pp.143-158
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• 1997

Electrochemical deionization (EDI) offers continuous demineralization at higher water recovery rates (>90%), compared with mixed bed ion exchange, and without the use of chemical regenerants and the associated production of saline waste water. Although EDI technology has been used in some power generation applications, its wider application requires the satisfactory resolution of outstanding capital cost and performance issues. This paper reports on the field evaluation of a new cost-effective EDI technology in a power generation application. The E-Cell System$^{TM}$, which became commercially available in the fourth quarter of 1996, consists of a rugged, modular system, based on a new high-performance EDI stack. Starting in May 1996, a 100 gpm modular EDI pilot system, rated for operation at 100 psi, was evaluated at the TVA Brown's Ferry Nuclear Plant. The feed consisted of Reverse Osmosis (RO) permeate with a conductivity of 4-7 $\mu$S/cm. The pilot system reliably produced 17.8-18.0 M$\Omega$.cm water under design operating conditions, independent. Silica levels were reduced from ca. 50 ppb to 4 ppb, while TOC levels were reduced from ca. 120 ppb to 30 ppb.

• Journal of Species Research
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• 제12권4호
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• pp.368-373
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• 2023

The genus Acymatopus Takagi is reported for the first time from Korean fauna along with two nominate species, A. minor Takagi, 1965 and A. takeishii Masunaga, Saigusa & Yang, 2005. This genus belonging to the subfamily Hydrophorinae in the family Dolichopodidae. It comprised of only six species in the world and distributed only in Japan and China thus far. The genus is diagnosed by a metallic bluish-green body with thick gray tomentum, lacking black and white markings of mesonotum, 2 pairs of long marginal setae at scutellum and male's dorsally slightly curved fore tarsomere 1. Both adults and larvae of this genus are known to be found on rugged and rocky marine shores of the tidal zone. The authors found the first recorded species in the west seaside of Korea, where many barnacles inhabit. The descriptions and illustrations of external features including male genitalia of newly recorded species are provided in this paper.

• 한국농림기상학회지
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• 제7권1호
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• pp.66-77
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• 2005

과정-중심적인 생지화학 모형인 BIOME-BGC을 이용해 기복이 심한 산림유역에서 미기후가 순일차생산성(NPP)의 시공간적 변화에 미치는 영향을 조사하였다. 임분규모에서의 물과 탄소순환과정에 대한 모형예측 을 검증하기 위하여 2000년부터 각각 낙엽활엽수림 (DBF)과 상록침엽수림(ENF)에서 현장 조사를 수행하였다. 모형예측은 지온, 토양수분, 토양호흡 등의 다양한 현장 측정치들과 높은 상관성을 보였다. 모형에서 예측한 NPP의 계절변화는 기온과 높은 상관성을 보였으나, 물 관련 인자들과는 통계적으로 유의한 상관성이 나타나지 않았다. 반면에 여러 인자 중에서, 강우빈도가 NPP의 연변화를 설명하는 가장 좋은 기후인자로 판명되었다 또한 DBF 임분보다 ENF 임분의 NNP가 강우빈도에 보다 민감한 것으로 나타났다. 공간적인 NPP 분포는 조사 유역에서 식생피복 및 지형의 기복에 따라 매우 이질적으로 나타났는데, NPP 이질성의 정도는 NPP의 절대량과 음의 상관관계를 보였다. 이러한 결과는 생육환경이 부적절할 때에 산림경관에서의 NPP 이질성이 커짐을 보여준다. 본 연구결과에 의하면 본 조사유역의 NPP는 연간 1,400mm 이상의 많은 강우에도 불구하고 식생이 이용할 수 있는 물의 양에 의해 제한 받는다는 것을 알 수 있었으며, 이러한 모형연구결과는 향후 현장조사를 통하여 검증할 필요가 있다.

• 한국환경생태학회지
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• 제28권2호
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• pp.205-214
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• 2014

본 연구는 부산광역시 지정 기념물 제 46호인 동백섬에 대해 문화경관림으로서의 식생관리방안을 제시하고자 하였다. 연구대상지는 동백섬 내 자연휴식년제 지역인 정상부 주변 $20,000m^2$이었다. 지형, 식생, 식생관리현황을 기준으로 식생구조 유형을 분류하였으며 유형별 식물군집구조 분석을 통해 관리방안을 도출하였다. 식생구조 유형은 관리되고 있는 동백나무림, 관리되지 않은 사스레피나무림, 험준지의 미관리된 사스레피나무림 등 3개로 구분되었으며, 식물군집구조 분석결과, 교목층에서는 곰솔이 우점하였고 아교목층에서는 동백나무(유형 I), 사스레피나무(유형II, III)가 우점하였다. 특히, 관목층을 중심으로 난대림의 극상수종인 후박나무가 일부 분포하였다. 흉고직경급별 분석결과, 유형 I, II에서 중경목의 팽나무와 후박나무가 일부 분포하였고 모든 유형의 관목층에서 후박나무가 4~44주 생육하였다. 교목층의 평균 수령은 66년, 아교목층은 22.9년이었으며 종다양도는 0.5472~0.8646로 분석되었다. 동백섬의 식생관리 방향으로서 기존 관리된 동백나무림은 주기적인 관리를 유지하며 관리되지 않은 사스레피나무림은 사스레피나무를 제거하고 동백나무를 식재하는 관리를 제안하였다. 관리되지 않은 험준지 사스레피나무림은 동백나무경관 형성이 불가능 할 것으로 예측되어 상록활엽수림으로의 천이유도 방안을 제시하였다.

• 한국동물위생학회지
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• 제42권4호
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• pp.289-296
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• 2019

A novel rapid procedure with liquid chromatography tandem mass spectrometry (LC-MS/MS) detection has been developed by changing various conditions including sample preparation such as QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) methodology. This work has been involved the optimization and validation of detection method for fluoroquinolones which are widespread used in livestock especially in the chicken. Five grams of homogenized chicken muscle were extracted with QuEChERS EN and acetonitrile containing 5% formic acid and cleaned with anhydrous magnesium sulfate and C₁₈ sorbent. The separation was performed on Acquity UPLC HSS T3 (2.1 mm×100 mm, 1.8 ㎛) column. The mobile phase A and B were composed of water containing 0.1% formic acid and acetonitrile containing 0.1% formic acid, respectively. Flow rate was 0.25 mL/min and column temperate was 40℃. LC-MS/MS with multiple reaction monitoring has been optimized for ten fluoroquinolones (ciprofloxacin, danofloxacin, difloxacin, enrofloxacin, marbofloxacin, norfloxacin, ofloxacin, orbifloxacin, pefloxacin and sarafloxacin). The method developed in this study has been presented good linearity with correlation coefficient (R²) of 0.9971~0.9998. LOD and LOQ values ranged from 0.09 to 0.76 ppb and from 0.26 to 2.29 ppb, respectively. The average recoveries were from 77.46 to 111.83% at spiked levels of 10.0 and 20.0 ㎍/kg. Relative standard deviation (%) ranged 1.28~11.90% on intra-day and 3.10~8.38 % on inter-day, respectively. This analysis method was applicable to the livestock residue laboratories and was expected to be satisfactory for the residue surveillance system.

• 농약과학회지
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• 제15권4호
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• pp.417-433
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• 2011

QuEChERS(quick, easy, cheap, effective, rugged and safe) 전처리법과 HPLC-MS/MS의 기기분석조건을 확립하고 분석법을 검증하였다. 상추와 사과에 첨가농도 90, 45, 9 ng/g로 농약을 처리하고 상추의 경우 GCB를 첨가하고 사과의 경우 GCB를 첨가하지 않고 QuEChERS법으로 전처리 한 후 HPLC-MS/MS로 분석하여 matrix matched calibration을 이용하여 회수율을 조사한 결과, 첨가된 농약 240성분 중 회수율이 70~120%이고 RSD가 20% 이하인 농약은 사과의 경우 218성분(91%), 상추의 경우 207성분(86%)이었다. 또한 lowest calibrated level(LCL)은 192성분이 4.5 ng/g, 42성분이 9 ng/g, 3성분이 45 ng/g이었으며 3성분은 검출이 불가능하였다. 따라서 본 시험에서 사용된 QuEChERS 전치리법과 HPLCMS/MS 분석조건을 이용하여 국내 등록 농약에 대한 야채와 과일중의 잔류농약 분석이 가능할 것으로 판단되었다.