• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.17 no.3
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• pp.205-211
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• 1999

In this study, we utilized 2D conformal transformation method to give coordinatesbased on GPS surveying data to NAHMIS (National Highway Management Information System) drawings which are lack of coordinates. To determine the best method which is comparable with GPS digital map, we compared a transformation result obtained by unique parameters applied to the whole region of about 20 km of the NAHMIS drawings and the similar result of the tile based transformations. As the result of map joining, the error was within 2 m for both cases. In this way, NAHMIS can be used for a systematic management of construction drawings. Moreover, NAHMIS can contribute the management of highway and the data exchange between other systems by a unification of coordinate system.

• Korean Journal of Ichthyology
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• v.17 no.4
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• pp.258-263
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• 2005

Feeding habits of Hapalogenys mucronatus (10.1~22.1 cm) collected from coastal waters off Sori Island, Yeosu, from June 2003 to May 2004 were studied. H. mucronatus is a carnivore which consumes mainly caridean shrimp, crabs, polychaetes, and amphipods. Its diet includes small quantities of bivalves, cephalopods, seagrass, hermit crabs, isopods, eggs, mysids, gastropods, and copepods. H. mucronatus undergoes significant size-related changes; smaller fish (10~11.9 cm) prey mainly on amphipods, shrimps and bivalves, while the proportion of caridean shrimp increases with fish size (12~17.9 cm). The larger fishes (18~22.1 cm) eat caridean shrimps and polychaetes.

• Korean Journal of Ichthyology
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• v.27 no.2
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• pp.142-148
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• 2015

The feeding habits of the Pacific cod Gadus macrocephalus were studied using 620 specimens collected by bottom trawl and pound net in the Southeast sea of Korea, from February 2012 to June 2013. Of 620 specimens, 192 contained food and 428 were empty. The total length (TL) of individuals used in this study ranged from 20.4 to 95.2 cm. Pacific cod mainly consumed Pisces, Macrura, and Cephalopoda. Its diet also included small quantities of Anomura, Brachyura, Mysidacea, Isopoda and Amphipoda. The proportion of Pisces in prey items increased with increasing Pacific cod length, but seasonal difference was not observed. The proportion of Macrura and Cephalopoda decreased with growth, and seasonal differences were apparent. Macrura were taken there mainly from autumn to winter, whereas Cephalopoda were consumed from spring to summer.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.20 no.2
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• pp.208-214
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• 2009

A design and its experimental result of a wideband self-complementary spiral antenna for UWB USPR(Ultrashort-Pulse Radar) system applications is presented. By utilizing the planar-type ultra-wideband microstrip-to-CPS balun, ultra-wideband characteristics of the inherent spiral antenna are retrieved. Also, the design procedure of the spiral antenna is simplified by performing simple impedance matching between separately designed balun and antenna. The proposed spiral antenna is equiangular self-complementary spiral antenna. The implemented antenna demonstrates widebaad performance for frequency ranges from 2.9 to 12 GHz with the relatively flat antenna gain of 2.7 to 5.3 dB and broad beamwidth of more than $70^{\circ}$. From these result, the possibility of a spiral antenna using a ultra-wideband microstrip-CPS balun is verified.

• Journal of Korean society of Dental Hygiene
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• v.12 no.5
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• pp.987-997
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• 2012

Objectives : This study was carried out in order to obtain basic data for students' efficient acquirement and instruction of radiography technology in the future by surveying dental hygiene students' recognition of periapical radiography. Methods : This study carried out a questionnaire survey targeting dental hygiene students from December 2009 to December 2010, and obtained the following results. Results : 1. As a result of examining recognition on periapical radiography, the bisecting angle technique was indicated to be averagely $3.84{\pm}0.566$ points. The paralleling technique was indicated to be $2.66{\pm}0.701$ points. 2. As a result of examining about problems given the bisecting angle technique, what had been most difficult given the bisecting angle technique was indicated to be the highest in cone positioning with 34.2%. The most difficulty given deciding on the X-ray vertical-angel irradiation direction was indicated to be the highest with 66.9% in adjusting the cone direction on the virtual bisector. 3. As a result of examining about problems given the paralleling technique, what had been most difficult in the process of the paralleling technique was indicated to be the highest with 56.7% in fixing the film immobilization device inside the mouth. Conclusions : Examining the above results, it is considered that there is a need of understanding morphological and anatomical structure inside the mouth in order to reduce the mistake rate given the periapical radiography, and that it is important to increase skill level by repetitively shooting several times with having enough time.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.3
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• pp.372-379
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• 1998

Feeding habits of Favonigobius gymnauchen collected from the eelgrass bed in Kwangyang Bay from January 1994 to December 1994 were studied. Favonigobius gymnauchen was a carnivore which consumed mainly gammarid amphipods, polychaetes, crabs and copepods. Its diets included minor Quantities of gastropods, tanaids and isopods. It showed ontogenetic changes in feeding habits. Small individuals (1$\~$2 cm) fed mainly on gammarid amphipods, polychaetes, and copepods. While the portion of the stomach contents attributable to polychaetes and crabs increased steadily with incensing fish size, consumption of copepods decreased progressively. Gammarid amphipods were the most selected prey item for all size classes. Although gammarid amphipods, polychaetes, crabs and copepods were major prey organisms for all seasons, the relative proportion of these food items changed with season. Consumption of copepods was relatively high in spring and fall and consumption of gammarid amphipods, polychaetes and crabs was relatively high in summer.

• Spatial Information Research
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• v.11 no.4
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• pp.481-491
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• 2003

This study aims at generating a continuous map by coordinates transformation between cadastral maps with different surveying origins. The continuous cadastral map is useful in various fields of GIS. For this purpose, an experimental study was conducted at Osan-Si, Kyonggi Province in cooperation with related institutions. In this study, three control point zone, large, medium, and small zone were to!;ted. For each control point, the currently used data were compared with the data at the surveyed time. About coordinate transformation method, we tested Helmert, Affine, and Polynomial methods which are the most representative among 2-dimensional coordinate transformations. These three transformation methods were evaluated according to variation of transformed parcel shape and agreement with neighboring areas. As the result of the evaluation, Affine transformation in large zone is the most appropriate coordinate transformation method fer Osan-Si.

• Korean Journal of Ichthyology
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• v.24 no.2
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• pp.77-83
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• 2012

The feeding habits of the marbled flounder Pleuronectes yokohamae were studied using 395 specimens collected from January to December, 2010, in the coastal waters off Tongyeong, Korea. The size of P. yokohamae ranged from 10.5 to 38.8 cm in standard length (SL). P. yokohamae is a bottom-feeding carnivore that consumes mainly bivalves, amphipods and polychaetes. Its diet also includes small quantities nemertians, anthozoan, isopods, copepods, tanaidacean, shrimps, crabs and ophiuroids. Our feeding-strategy graphical method reveled that P. yokohamae was a generalized feeder, with a wide niche width. P. yokohamae mainly consumed bivalves, amphipods and polychaetes, and did not show significant ontogenetic changes in feeding habit without size over 22 cm. Prey size did not increase significantly as growing fish size.

• Journal of Aquaculture
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• v.13 no.4
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• pp.309-316
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• 2000

Feeding habits of A. luridus were studied by analyzing the stomach contents of monthly collected fish from the intertidal zone of Dodun-ri, Sochon from July 1996 to June 1997. Fullness of stomach increased twice a day, first in the morning and second in the afternoon. A. luridus (1.2-5.9 em in standard length) was a carnivore consuming mainly decapods (natantia larvae, Acetes japonicus, Penaeus japonicus and reptantia larvae), amphipods (caprellids, gammarids and hyperiids) and copepods (Acartia sp., Calanus sinicus, Corycaeus affinis, and Microsetella sp.). Its diets also included minor quantities of isopods, cirriped larvae, polychaete larvae and stomatopods. According to fish size, some changes in feeding habits were apparent, i.e. smaller fish preferred to prey in the following order : copepods < decapods < amphipods. However, as the size increased, decapods and amphipods were selected.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.39 no.7
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• pp.26-36
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• 2002

Mach-Zehnder type traveling-wave optical modulators with 3-section and 5-section phase reversal were designed and fabricated on z-cut $LiNbO_3$ substrates. Optical waveguides were designed by means of the FDM(Finite Difference Method). Design of CPW traveling-wave electrodes were performed by the SOR(Successive Over Relaxation) in the active region and by the CMM(Conformal Mapping) in the input/output section. The optical response R(${\omega}$ calculated based on the measured S-parameters showed the bandwidth of 15GHz centered at 25GHz for the 3-section, and the bandwidth of 22GHz at 45GHz for the 5-section.