• The KIPS Transactions:PartC
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• v.12C no.3 s.99
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• pp.429-436
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• 2005

A mobile ad hoc network (MANET) is a collection of mobile nodes without any fixed infrastructure or my form of centralized administration such as access points and base stations. The ad hoc on-demand distance vector routing (AODV) protocol is an on-demand routing protocol for MANETs, which is one of the Internet-Drafts submitted to the Internet engineering task force (IETF) MANET working group. This paper proposes a new multipath routing protocol called maximally disjoint multipath AODV (MDAODV), which exploits maximally node- and link-disjoint paths and outperforms the conventional multipath protocol based on AODV as well as the basic AODV protocol. The key idea is to extend only route request (RREQ) message by adding source routing information and to make the destination node select two paths from multiple RREQs received for a predetermined time period. Compared to the conventional multipath routing protocol, the proposed MDAODV provides more reliable and robust routing paths and higher performance. It also makes the destination node determine the maximally node- and link-disjoint paths, reducing the overhead incurred at intermediate nodes. Our extensive simulation study shows that the proposed MDAODV outperforms the conventional multipath routing protocol based on AODV in terms of packet delivery ratio and average end-to-end delay, and reduces routing overhead.

• Communications for Statistical Applications and Methods
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• v.16 no.6
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• pp.891-901
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• 2009

In this paper, we investigate the approach to estimate VaR under the transformed GARCH model. The time series are transformed to approximate to the underlying distribution of error terms and then the parameters and the one-sided prediction interval are estimated with the transformed data. The back-transformation is applied to compute the VaR in the original data scale. The analyses on the asset returns of KOSPI and KOSDAQ are presented to verify the accuracy of the coverage probabilities of the proposed VaR.

• Korean Journal of Optics and Photonics
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• v.10 no.3
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• pp.243-247
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• 1999

We report the generation of inherently stable, high-speed, nearly transform-limited, optical pulses by chirped pulse compression, in which sinusoidally driven phase modulator generates frequency chirped pulses that are subsequently compressed by a dispersive optical fiber. Experimental results show that $sech^2$ shape pulses with a pulse width of ~14 ps and a time bandwidth product of ~0.34 are successfully generated at 10 GHz repetition rate. In contrast to other methods, such as higher order soliton compression, this approach does not depend on the optical power and thus shows promise for application to low-power lasers.

• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.4
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• pp.407-419
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• 1983

In this study, the lipid components of three species of shellfish included oyster(Crassostrea gigas), top shell(Turbo cornutus) representing salt water shellfish and corb shell(Corbicula fluminea producta) representing flesh water shellfish were analysed and nutriontional significances were discussed. Analysed the total lipid composition, and the fatty acid and sterol composition of total lipid were determined. The lipid was fractionated into three lipid classes neutral, glyco and phospholipid by column chromatography. The fatty acid composition of each lipid class and sterols were determined by gas liquid chromatography. The lipid components of total lipid and neutral lipid were estimated by thin layer chromatography and TLC scanner. The results were as follows: Total lipid contents of shellfish were 1.8% in oyster, 0.4% in top shell and 4.0% in corb shell. The contents of total fatty acid in total lipid were 80.7, 71.2 and 73.2%; and the contents of unsaponifiable matters were 15.4, 18.1 and 23.1% respectively. Total lipids were mainly composed of triglycerides, polar lipid-pigments and sterols as major component, and hydrocarbon-esterified sterols were determined in each sample. The major fatty acids in total lipid were palmitic(37.0%), eicosapentaenoic(13.5%) and linoleic acid(11.2%) in oyster, Octadecatetraenoic(15.8%), palmitic(11.2%), oleic(8.6%) and linoleic acid(8.1%) in top shell, but palmitic(34.0%), linoleic(12.3%) and paimitoleic acid(9.8%) in corb shell. Particularly, the contents of eicosapentaenoic acid of oyster and top shell were higher than those of corb shell. Sterol composition from three species of shellfish were mainly consisted of cholesterol (42.7~64.0%), brassicasterol(15.6~24.7%) and 24-methylenecholesterol (4.7~21.9%). But sitosterol (5.3%) was detected only in oyster and 22-dehydrocholesterol(12.9%) was only in top shell. The contents of fractionated neutral lipid was commonly higher than that of polar lipid in each sample. Glycolipid and phospholipid in polar lipid showed similar in quantity. The neutral lipids were composed of triglycerides(33.0~36.7%), free sterols(25.7~31.2%), esterified sterol(12.4~23.7%) and free fatty acids(5.1~11.7%). The contents of triglycerides and free sterols were higher than those of free fatty acids and esterified sterols. The major fatty acids in neutral lipid were palmitic(28.4~26.4%) eicosapentaenoic(18.6~21.9%) and linoleic acid(9.0~5.4%) in oyster and corb shell but octadecatetraenoic(14.5%), eicosapentaenoic (13.5%) and palmitic acid(12.3%) in top shell. The major fatty acids in glycolipid were eicosenoic(10.2%), palmitic(12.1%) and linolenic acid (10.2%) in oyster, Eicosenoic(26.0%), octadecatetraenoic(14.6.%) and eicosadienoic acid(12.9%) in top shell. But eicosadienoic(21.4%) stearic(14.6%), octadecatetraenoic(8.5%) and eicosenoic acid(8.5%) in corb shell. The major fatty acids in phospholipid were myristic(16.0%), stearic(10.6%), eicosenoic(10.5%) and palmitic acid(10.3%) in oyster, Oleic(22.2%), stearic(20.7%) and linolenic acid (11.8%) in top shell but eicosapentaenoic(25.1%), myristic(8.7%) and arachidonic acid(8.3%) in corb shell.

• 한국ITS학회:학술대회논문집
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• 2010.05a
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• pp.188-192
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• 2010

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.7
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• pp.1266-1274
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• 2006

A non-overlap boosted-clock charge pump(NBCCP) with internal pumping capacitor, an advantageous circuit from a minimizing point of TFT-LCD driver IC module, is proposed in this paper. By using the non-overlap boosted-clock swinging in 2VDC voltage, the number of pumping stages is reduced to half and a back current of pumping charge from charge pumping node to input stage is also prevented compared with conventional cross-coupled charge pump with internal pumping capacitor. As a result, pumping current of the proposed NBCCP circuit is increased more than conventional cross-coupled charge pump, and a layout area is decreased. A proposed DC-DC converter for TFT-LCD driver IC is designed with $0.18{\mu}m$ triple-well CMOS process and a test chip is in the marking.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.12 no.7
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• pp.1157-1166
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• 2001

In this paper, we investigated the degree of compensation for optical pulse shape distortion due to both chromatic dispersion and SPM(self phase modulation) in high speed optical transmission system with dispersion shift fiber. We adopted the power symmetric MSSI(mid-span spectral inversion) as compensation method. We used EOP(eye-opening penalty) parameter in order to evaluate the compensation efficiency of distorted optical pulse. We evaluated input signal power range being able to maintain stable reception performance in the case of various chirp parameter of modulated optical pulse. And, in order to verify the applicable to wideband WDM system, we evaluated the wavelength range being able to maintain stable reception performance through the EOP calculation of various dispersion coefficient of first fiber D$\_$11/. We showed that proposed MSSI is effective compensation method to down chirped optical pulse transmission rather than up chirped optical pulse transmission in anomalous dispersion range. And we showed that this method have possibility of relative high power transmission and wideband transmission in WDM system.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.29 no.2
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• pp.138-141
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• 2018

In this paper, we describe the designed digital waveform of a linear frequency-modulated (FM) chirp signal using field-programmable gate arrays (FPGAs) for image radar, and this signal is modulated with an I-Q modulator, and multiplied by 24 frequency multipliers to obtain a 94-GHz W-band wideband chirp generator. The developed chirp generator is an FM signal with a 94-GHz carrier frequency and a 960-MHz bandwidth, and the flatness is less than 1.0 dB at intermediate frequency (IF) (3.9 GHz), 2.0 dB in the W-band, and it has a 0.3-W output power in the W-band.

• Korean Journal of Heritage: History & Science
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• v.56 no.2
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• pp.100-121
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• 2023

This paper examines the interior settings of a chamber and of a temporary place of enshrinement at Yeonghuijeon (永禧殿, Hall of Eternal Happiness), the representative official portrait hall in which portraits of early and late Joseon kings were enshrined. Also, it discusses the features of the Five Peak screens used therein. The physical environment of a chamber at Yeonghuijeon mainly consisted of a four-panel folding screen with a painting of Five Peaks and a large wooden platform, which was adorned with dragon and lion patterns and attached to lotus-leaf column balustrades. The Five Peak screen was installed on a large platform in the shape of ⊓, spreading across the second and third panels on the back and folding out on the first and fourth panels on the right and left sides. When a portrait was enshrined in a temporary place, a simpler and smaller platform with railings was used. A four-panel folding screen of the Five Peak painting was installed in the same way as in a chamber, but was unfolded around a smaller platform behind it. A royal portrait was displayed in each chamber, whereas a case in which a portrait was rolled up was put on the smaller platform in a temporary place. The Five Peak screens for a chamber and a temporary place were all large four-panel folding screens with two wide panels in the middle and two narrow panels on each side, and only strips of silk were mounted on the four edges of the screens without additional wide lower-side mountings. While screens for the chamber used patterned silk for mounting and white paper for backing on screen frames, screens for the temporary place used plain silk and recycled failed test papers for mounting and backing, respectively. By examining records in the literature on the Five Peak screens for Yeonghuijeon, this paper highlights two Five Peak screens, both of which lost their provenance from the hall. The structures of the two screens reflected the way they were to be installed at the hall. Furthermore, this paper assumes that a Five Peak screen, which had been unfolded on the throne in the main hall of Changdeokgung Palace after the 1960s, was produced in 1858 for the purpose of temporarily enshrining King Sunjo's portrait due to the fact that failed test papers of the 1840s were laid taut over the frame.

• The Korean Journal of Malacology
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• v.30 no.2
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• pp.107-116
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• 2014

Gonadal development and maturation mechanism were studied on the freshwater marsh clam Corbicula papyracea (Heude), which is the endangered species in Korea. The specimens were collected in the rearing ponds and waterway of NFRDI in Gapyeong-gun, Gyeonggi-do from January to December 2004, and then investigated by condition factor, relative growth, gonadal development phases and gonad histological characters based on 30-50 individuals every month. Comparing with the freshwater marsh clam, C. papyracea is small, light olive brown shell and violet interior. The hermaphrodite individuals of C. papyracea take an internal fertilization and fertilized eggs are stored in the foster-sack in the gills, then the hatched juveniles are released outside after an ovoviviparous process. The average water temperature of inhabit area was in range of $1.8-27.0^{\circ}C$ and usually took great effects on the gonad maturation of C. papyracea. The condition factor ranged from 0.14 to 0.21 throughout the year, which was the lowest during winter season (December-February), and gradually increased to the highest value of 0.21 in May. The ratio of meat weight to total weight was 25.9-38.7%, indicating the similar trend with condition factor. The highest values of condition factor and the ratio of meat weight appeared 1-2 months later than gonadosomatic index reached the peak value, it was probably because that the ovoviviparous eggs would spend a long period before hatching from the foster-sack in the gills. To synthesize the characters of meat weight, condition factor and gonad development by histological study, reproductive cycle of C. papyracea could be divided into five successive stages: multiplicative stage (December to February), growing stage (February to May), mature stage (June to August), spawning stage (August to November), recovery stage (November to December). The smallest shell length of matured C. papyracea was 12.6 mm, and individuals, larger than 16 mm, was formed the nursery in the gills.