• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 하계종합학술대회 논문집
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• pp.914-917
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• 1999

The paper describes a 17 $\times$ 17-b multiplier using the Radix-4 Booth’s algorithm. which is suitable for 32-bit RISC/DSP microprocessors. To minimize design area and achieve improved speed, a 2-stage pipeline structure is adopted to achieve high clock frequency. Each part of circuit is modeled and optimized at the transistor level, verification of functionality and timing is performed using HSPICE simulations. After modeling and validating the circuit at transistor level, we lay it out in a 0.35 ${\mu}{\textrm}{m}$ 1-poly 4-metal CMOS technology and perform LVS test to compare the layout with the schematic. The simulation results show that maximum frequency is 330MHz under worst operating conditions at 55$^{\circ}C$ , 3V, The post simulation after layout results shows 187MHz under worst case conditions. It contains 9, 115 transistors and the area of layout is 0.72mm by 0.97mm.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 I
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• pp.633-636
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• 2003

An Ethernet passive optical network(EPON) is a point-to-multipoint optical network. EPONs leverage the low cost, high performance curve of Ethernet systems to provide reliable data, voice and video to end user at bandwidths far exceeding current access technologies. In this paper, we propose the economical and flexible structure of optical network unit(ONU) converting optical format traffic to the customer's desired format(Ethernet, VDSL, T1, IP multicast, etc.). A unique feature of EPONs is that in addition to terminating and converting the optical signal the ONU provide Layer 2-3 switching functionality, which allows internal routing of enterprise traffic at the ONU.

• Bulletin of the Korean Chemical Society
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• 제32권2호
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• pp.483-488
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• 2011

Present work comprises of synthesis various analogues of ciprofloxacin by introducing new functionality at carboxylic group position via ester aminolysis reaction. For this purpose the carboxylic group at C-3 was esterified and later subjected to nucleophilic attack at the carbonyl carbon by various aromatic amines. Structure of the analogues was confirmed by different techniques i.e. IR, $^1H$ NMR and mass spectrometry. The antibacterial activity of the derivatives was also assessed with the parent against a series of Gram-positive and Gram-negative bacteria. The synthesized compounds showed diverse antimicrobial profile among which most compounds possessed a comparable or better activity in comparison to the ciprofloxacin. Additionally unlike ciprofloxacin, some of the derivatives were also found to show antifungal activity.

• Natural Product Sciences
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• 제26권2호
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• pp.171-175
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• 2020

Liriodendron tulipifera, belonging to the family Magnoliaceae, is commonly called tulip tree. Four N-acetylated aporphine alkaloids, N-acetylnornuciferine (1), N-acetylanonaine (2), N-acetyl-3-methoxynornuciferine (3), and N-acetyl-3-methoxynornantenine (4) were isolated from the roots of L. tulipifera. Although the purity of each compound (1 - 4) was determined to be 97, 96, 99, and 98%, respectively, the ¹H and ¹³C NMR spectroscopic data of the aporphine alkaloids 1 - 4 displayed all signals in duplicate, indicating the presence of two rotamers due to restricted rotation of N-COCH₃ functionality in solution status. The absolute configurations of 1 - 4 w ere established by measuring specific rotation and comparison with the reported data. This is the first report on the ¹H and ¹³C NMR assignments of N-acetyl-3-methoxynornuciferine (3) and N-acetyl-3-methoxynornantenine (4). This study provides advanced NMR spectroscopic data for the structure determination of rotameric aporphine alkaloids.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 하계종합학술대회 논문집(5)
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• pp.69-72
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• 2000

This paper describes an SRAM write driver circuit which dissipates small power. The write driver utilizes a dual sized transistor structure to reduce operating current in the write cycle. In the case of higher voltage comparing to Vcc, only one transistor is active, while in the case of low Vcc two transistors are active so as to deliver the current twice. Thus though with the high voltage operation, the power consumption is reduced with keeping the speed in a given specification. Simulation results have verified the functionality of the new circuit and write power is reduced by 7 % per bit.

• 한국IT서비스학회지
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• 제6권2호
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• pp.125-143
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• 2007

IT Services market is growing rapidly in the business industry and SOA-based Web Services have been introduced as an effective vehicle for the integration of enterprise-wide applications within organizations. The number of publicly available Web Services is ever increasing recently in a variety of areas, and as the number of public Web Services increases, there will be many Web Services with the same functionality. These services, however, will vary in their QoS properties, such as price, response time and availability, and it is very important to choose a right service while satisfying given QoS constraints. This paper addresses the issue of selecting composite Web Services which involves conditional branches in business processes. It is essential to have any conditional branches satisfy the global QoS constraints at service selection phase, since the branches are chosen to execute at run-time dynamically. We proposed service selection procedures for basic structure of conditional branches and explained them by examples. Experiments were conducted to analyze the impact of the number of candidate services and service types on the time of finding service solutions.

• 한국지능시스템학회논문지
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• 제21권4호
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• pp.449-455
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• 2011

본 논문에서는 원격제어 시스템의 시간지연 문제를 분석하고 그 문제를 신경망으로 보상한다. 스미스 예측기는 시간지연 시스템에서 정확한 모델을 필요로 한다. 스미스 예측기의 모델링 오차를 보상하기 위해 신경회로망을 사용한다. 스미스 예측기를 구성하기 위해 Radial Basis Function(RBF) 신경회로망이 사용된다. 시뮬레이션과 실험을 통해 제안하는 방법의 동작을 검증한다.

• EDISON SW 활용 경진대회 논문집
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• 제4회(2015년)
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• pp.535-537
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• 2015

We present selfie stick case design, which can protect upper part of Selfie Stick. Many of current products are damaged when it is carried without cases, especially upper part of the product, because protection case is irrelevant to handle in urgent or frequent use of the product. To solve this problem, we design the case part which is attached to stick. For designing the part, we considered functionality, aesthetics, portability and profitability.

• 한국컴퓨터정보학회논문지
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• 제20권12호
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• pp.175-180
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• 2015

It is important to maintain information system (IS) following the business and institutional change. Even if successfully developed information systems, we cannot gain the benefit from the systems without the proactive maintenance activities. However, the importance of IS maintenance has not been considered as much as the system development, and we don't have any specific performance management structure. The objective of this study is to identify the relationship between IS maintenance activities and utilization. For empirical test of the hypothesis model, the sample data is collected from public information system sites. Results from multiple regression analysis reveal that proactive maintenance activities including IS maintenance cost increase, improving functionality, and enhancing ease of use have a causal effect on the IS utilization.

• Bulletin of the Korean Chemical Society
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• 제30권10호
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• pp.2294-2298
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• 2009

In present work an attempt was made to synthesize various analogues of levofloxacin by introducing new functionality at carboxylic group position via nucleophilic substitution reaction. For this purpose the carboxylic group at C-6 was esterified and later subjected to nucleophilic attack at the carbonyl carbon by various aromatic amines. Structure of the analogues was confirmed by different techniques i.e. IR, $^1H$ NMR and mass spectrometry. The antibacterial activity of the derivatives was also assessed and compared with the parent against a series of Gram-positive and Gramnegative bacteria. A synergistic as well as antagonistic behavior was observed in these derivatives. Additionally unlike levofloxacin, the derivatives were also found to modulate oxidative burst response of phagocytes exhibiting moderate to significant inhibitory activity.