• Korean Chemical Engineering Research
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• v.50 no.2
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• pp.304-309
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• 2012

Size verification of small and large bubbles in a bubble column was investigated by employing the dynamic gas disengagement (DGD) method and dual electrical resistivity probe (DRP) method, simultancously. The holdups of large and small bubbles in the bubble column in a given operating condition were obtained by means of the DGD method by measuring the pressure drop variation in the column with a variation of time after stopping the gas input into the column. The size and frequency of bubbles were measured by the DRP method in the same operating condition, from which the bubble holdup of each range of size was obtained. The verification of size in determining the large or small bubbles was decided by comparing the holdups of large or small bubbles measured by the DGD method with that measured by the DRP method. Filtered compressed air and tap water were used as a gas and a continuous liquid medium. The diameter and height of the bubble column were 0.102 m and 1.5 m, respectively. The demarcation size between the large and the small bubbles in the bubble column was 4.0~5.0 mm; the demarcation size was about 5.0 mm when the gas velocity was in the relatively low range, but about 4.0 mm when the gas velocity was in the relatively high range, within this experimental conditions.

• 주택과사람들
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• s.194
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• pp.62-65
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• 2006

'음악을 좋아한다'는 단순한 말로는 부족하다. 오케스트라의 작은 악기 소리까지 놓치지 않기 위해 몇 번이고 오디오를 손보는 그의 정성은 '음악'보다 더 작은 단위인 '소리'에 대한 열정이라고 말할밖에. 소리에 관한 예민한 감성과 청력을 가진 남자, CNP차앤박피부과의 심재홍 원장을 만났다.

• Aerospace Industry
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• s.106
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• pp.64-65
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• 2010

현대전에서 이제 빼놓을 수 없는 전략 중 하나가 바로 무인기. 특히 무인기 운용이 대폭 늘면서 크고 작은 다양한 무인기들이 전장의 하늘을 점령하고 있다. 이번 호에서는 작은 덩치에도 불구하고 해상 및 육상 전력의 매서운 눈 역할을 하고 있는 스캔이글에 대해 알아본다.

• 아름다운작은공간 미소공
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• v.29
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• pp.10-11
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• 2002

• Journal of Korean Library and Information Science Society
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• v.51 no.2
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• pp.187-212
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• 2020

It is expected that Gyeonggi-do Small Libraries will increase in quantity in the future due to the current SOC complex project being implemented by the government, and it is deemed that institutional and policy support must be provided with priority in order for the Small Libraries to grow qualitatively through the implementation of substantial measures. Based on the findings of this study, the reform measures proposed to revitalize Gyeonggi-do Small Libraries in terms of ordinances as follows: ① strengthen the library law and business promotion related to Small Libraries; ② enact the mandatory library law provisions for the installation of and support for Small Libraries; ③ even if there are relevant provisions in the 「Library Act」, the local governments' Small Libraries Support Ordinances should at least simply state that they must meet the criteria specified in the 「Library Act」; and ④ provisions on the number and qualifications of operating personnel of Small Libraries reflecting the number of users and the size of collections of books of Small Libraries of cities and counties.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.11
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• pp.2009-2014
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• 2017

A novel structure of phase locked loop (PLL) with a time constant comparator and a current compensator has been proposed. The proposed PLL uses small capacitors which are impossible for stable operation in a conventional PLL. It is small enough to be integrated into a single chip. The time constant comparator detects the loop filter output voltage variations using signals which are passed through small and large RC time constants. The signal from the large RC time constant node is the average of the loop filter output voltage. The output voltage of another node is approximately equal to the present loop filter voltage. The output of the time constant comparator controls a current compensator and charge/discharge small size loop filter capacitors. It makes the proposed PLL operate stably. It has been simulated and proved by HSPICE in a CMOS $0.18{\mu}m$ 1.8V process.

• Journal of Advanced Navigation Technology
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• v.14 no.5
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• pp.752-759
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• 2010

In this paper, we propose differential-logging method to improve the performance of RMW(Read Modify Write) operations of DDR-SSD based software RAID. Small writes that are frequently occurred in enterprise applications are main factor to degrade the performance of RAID5. Once a block is updated in RAID5, the parity block of the block must be updated to maintain consistency of parity. Therefore, to process a small write request, we need to read its parity block stored in disk, read old data, perform XOR operation, and write updated data and parity block. Several methods for hard disk based software RAID are proposed to solve the small write problems in RAID 5. Ln this paper, we propose a differential-logging method which carefully considers the DDR-SSD to solve the small write problem in RAID 5. We show that our proposed method out performs the existing software RAID in LINUX through simulations.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.14 no.5
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• pp.135-140
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• 2004

In Crypto 2002 May analyzed the relation between the size of two primes and private key in unbalanced RSA with small CRT exponent. Also in Crypto 2003 he showed that if $N^{1}$4/ amount of most significant bits(least significant bits) of $d_{p}$ is exposed in balanced RSA with CRT, N can be factored. To prove this he used Howgrave-Graham's Theorem. In this paper we show that if $N^{1}$4/ amount of $d_{p}$ , p is smaller than q, and bigger than $N^{0.382}$ to avoid May's attack, is exposed in unbalanced RSA with small CRT exponent, it is enough to expose $d_{p}$ . We use Coppersmith's theorem with unbalanced primes.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.41 no.7
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• pp.435-443
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• 2017

The Characteristics of the flowfields of a square prism having a small square prism were investigated by measuring of lift and drag on the square prism and visualizing the flowfield using PIV. The experimental parameters were the width ratios(H/B=0.2~0.6) of small square prisms to the prism width and the gap ratios (G/B=0~3) between the prism and the small square prism. The drag reduction rate of the square prism initially increased and then decreased with the G/B ratio for the same H/B ratio, and increased with the H/B ratio for the same G/B ratio. The maximum drag reduction rate of 98.0% was observed at H/B=0.6 and G/B=1.0. The lift reduction rate of the square prism was not affected by the width and gap ratios; the total average value was approximately 66.5%. In case of a square prism having a small square prism, the stagnation regions were represented in the upstream and downstream sides of the square prism.

• Journal of Korean Library and Information Science Society
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• v.41 no.1
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• pp.77-98
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• 2010

Recently, small libraries have greatly increased by the support and interest of the central, or local government. Since 2004, 47 small libraries were established in Jeon-buk province. These libraries are equipping a new facility and collection with their support. Nevertheless, they still have many problems in operating process. This is causing degradation of the quality level of information service for local residents, further, this becomes the obstacle which solves a information divide and improves the cultural welfare. The purpose of this study is to analyze the status of small libraries in Jeon-buk province, and then, to propose solutions to problems.