• 한국정밀공학회지
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• 제30권4호
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• pp.403-408
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• 2013

In this paper, the characteristics of ablation processing of the eagle glass by pico-second laser are investigated. The laser ablation is used to process micro forms on materials. The ablation causes little thermal effect and little burr on the surface of eagle glass. In order to examine the characteristics of panic cracks, experiments are conducted under various cutting conditions such as a frequency of 600 kHz, laser powers, scan speeds and number of scan(NS). To minimize the panic cracks, the specimens are heated at $30^{\circ}C$, $45^{\circ}C$, and $60^{\circ}C$ for ten minutes respectively and then they are broken by hands. Laser powers, NS and scan speeds have an effect on glass cutting results. The ablation depths increase with an increase in the laser power and NS whereas the panic cracks decrease with an increase in scan speed. The high temperature on processed specimens reduces the panic cracks and makes good results of laser cutting. The optimal condition for eagle glass laser cutting is found to be at 30 W of laser power, 3 mm/s of scan speed and 500 of NS, respectively.

• 한국전자파학회논문지
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• 제12권3호
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• pp.439-445
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• 2001

본 논문에서는 상용의 루비듐 원자시계를 이동용 기준시계로 사용시 시간오차를 최소화할 수 있는 방법을 제시하였다. 일반적으로 사용되고 있던 직선적인 보간법이 장기안정도를 고려하지 않았으나 새로운 방법에서는 시간오차를 줄이고자 장기안정도를 고려하였다. 두 가기 방식에 대한 비교측정결과, 관측시간이 1.5일 이내일때는 장기안정도를 고려한 시간오차예측이 기존의 방식에 비해 작은 시간오차가 자았다. 또한 루비듐 원자시계의 이동용 기준기로의 역할이 12시간 이내에 완료될 경우 새로운 방법은 최대시간오차가 기존 방법의 15 ns 보다 작은 10 ns 정도의 오차범위 내에서 사용 가능하다.

• 한국양식학회지
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• 제10권1호
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• pp.17-24
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• 1997

한국산 갯지렁이류 중에서 산업적으로 가장 중요한 청충의 양식기법 개발에 관한 기초자료를 얻기 위하여, 실내에서 인공사육한 청충의 생식과 발생에 관하여 조사한 결과는 다음과 같다. 1. 0.4~2.4 g의 청충을 자연수온 및 $20.0\pm1.0^\{\circ}C$와 $25.0\pm1$의 가온구에서 사육한 결과, 생식형의 체중(Wt)과 산란량(NS)과의 관계는 NS=48635.5897Wt 상(1.3044) (r=0.8572)의 식으로 나타났다. 2. Atokous segment 는 암컷이 23~28(평균24.8$\pm1$), 수컷은 22~29(평균24.6$\pm2$)개로 같았고, 체색에 의한 암수의 차이는 없었다. 3. 수정란의 난경은 $220\mu m$으로, 수정 21.0~$23.0^{\circ}C$에서 수정후 56시간 만에 부화하였다.

• Food Science and Biotechnology
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• 제18권3호
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• pp.739-744
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• 2009

This study aims to evaluate the therapeutic action of administration of Nigella sativa (NS) and Peganum harmala (PH) oils in diabetes and hepatic toxicity. Results show that treatment of diabetic rats with NS oil or PH oil ameliorate hyperglycaemia induced stress oxidative and hepatic dysfunction in diabetic rats. Administration of NS or PH oil to diabetic rats caused an anti-diabetic and antioxidant activities by the decrease in plasmatic glucose level and increase in hepatic superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX) activities, reduced glutathione (GSH) and glycogen contents compared to untreated diabetic rats. Besides, NS and PH oils protect the hepatic function observed by decrease of triglyceride (TG), total cholesterol (TCh), and increase of high density lipoprotein-cholesterol (HDL-Ch) levels in serum and hepatic tissues. Moreover, a diminution in the bilirubin, transaminase glutanic pyruvic (TGP), and transaminase pyruvic oxaloacetic (TPO) contents in serum and the thiobarbituric acid-reactive substances levels (TBARs) in hepatic tissues are also detected.

• 한국수학교육학회지시리즈A:수학교육
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• 제49권3호
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• pp.329-341
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• 2010

In this paper, we analyzed the freshmen's achievements on general mathematics their GPA based on 'basic mathematics diagonal test score'. Also, we studied the achievements of students who were not passed the 'Basic Mathematics Diagonal Test (BMDT)' and had to take supplementary lessons to improve their mathematics abilities four times a week during the first semester of academic year 2008 in Mokpo National University. Before taking college entrance exam, high school students had to choose two types of scholastic area. One is on 'Ga' or 'Na' in mathematics and the other is on Natural Science or Social Science. According to the types, we classified the freshman-Ga or Na and NS or SS. We found some facts. First, a few of Ga and NS freshmen had low score on the BMDT. Second, Na and NS freshman got higher score than Na and SS freshmen on the BMDT. Third, Ga and NS freshmen who passed the BMDT got higher score on the general mathematics than those who failed the BMDT. Finally, there are correlations between achievements of general mathematics and a curriculum of freshmen who were passed test after taking supplementary lessons.

• Imaging Science in Dentistry
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• 제35권3호
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• pp.175-178
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• 2005

Necrotizing sialometaplasia (NS) is a rare, benign, self-limiting lesion, but it mimics carcinoma both clinically and histologically. Authors present a case of NS on the right posterior hard palate in a 16-year-old boy. This case showed underlying erosive bone change on CT images. We supposed this lesion resulted from the local anesthesia for dental treatment. Presented NS is the only one case from approximately 1,500 oral and maxillofacial biopsies $(0.07\%)$ at Chonnam National University Hospital during the period from 1999 to 2004.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1988년도 전기.전자공학 학술대회 논문집
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• pp.311-314
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• 1988

This paper describes 256k (256K ${\times}$1) CMOS SRAM utilizing 1.2um double-polysilicon and double-metal CMOS process. A typical access time of 16ns with a 30-pF load has been achieved through the use of a block architecture, a new decoder, an unique bit-line scheme and an optimized process. Operating current is 55mA at 40MHz and 15mA at 10MHz. A high-resistive polysilicon load has been used to achieve a standby current of 3uA.

• 한국생산제조학회지
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• 제19권3호
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• pp.402-406
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• 2010

Conventionally, the machined surface roughness in nano-second(ns) laser machining is damaged and rough due to thermal effects. To obtain the improved surface finish, the ultrasonic vibration is applied to ns-laser machining. The ultrasonic vibration jig is developed to apply the ultrasonic high precision motion to workpieces. And then the ns-laser machining is conducted to compare the effects of the ultrasonic vibration. The results show that the surface roughness with ultrasonic vibration is smoother than that without the vibration. The phenomenon could be explained as enhancement of heat transfer by ultrasonic vibration.

• 한국미생물·생명공학회지
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• 제23권3호
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• pp.322-328
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• 1995

A thermophilic bacteria showing proteolytic activity against defatted soybean was isolated from soil. It was identified as Bacillus amyloliquefaciens based on its morphological and physiological characteristics. The Bacillus amyloliquefaciens NS 15-4 was cultivated at 50$\circ$C by rotary shaking in a medium containing defatted soybean. An extracellular protease from this strain was purified to homogeneity by ammonium sulfate precipitation, ion exchange, and hydrophobic interaction chromatographies. The molecular weight of the enzyme was estimated to be approximately 30,000 by SDS-PAGE and the N-terminal amino acid sequence of the enzyme was turned out to be AQSVPYGISQIKAPA. The optimum temperature and pH for the enzyme reaction were 60$\circ$C and 11, respectively, and its thermostability was increased by the addition of calcium ion. The enzyme was inactivated by phenylmethylsulfonylfluoride, suggesting it be a serine protease. Comparing with other commercial proteases, the enzyme showed relatively high proteolytic activity against defatted soybean, a water-insoluble protein substrate.

• Journal of Microbiology
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• 제33권3호
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• pp.260-266
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• 1995

Hepatitis C virus (HCV) has been considered as a mojor causative agent of post-transfusion related non-A, non-B hepatitis. In this study, the cDNA sequence of NS4 region of HCV (HCV-S) obtained from a Korean patient's plasms was determined. Comparative nucleotide sequence analysis between to type II. 67.2% homology to type III, and 66.4% homology to type IV. The putative amino acid sequence homologies to types I, II, III, and IV were 82.8-84.7%, 92.5-95.1%. 72.5, and 71.1%, respectively. This data strongly suggests that HCV-S should be classified as type II. Significant similarities of hydrophobicity profiles and putative transmembranous domains were found in HCV-S and four major prototypes, indicating that the protein structure is similar in spite of the heterogeneities of intertype homologies at the level of the psrimary nucleotide and amino acid sequences.