• Journal of IKEEE
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• v.2 no.1 s.2
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• pp.1-14
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• 1998

In this paper, Antenna, LNA, Mixer, VCO, and Modulation/Demodulation in Baseband processor which are the RF main components in Wireless LAN system for ultra high-speed communications network are studied. Antenna bandwidth and selective fading due to multipath can be major obstacles in high speed digital communications. To solve this problem, wide band MSA which has loop-structure magnetic antenna characteristics is designed. Distributed mixer using dual-gate GaAs MESFET can achieve over 10dB LO/RF isolation without hybrid, and minimize circuit size. As linear mixing signal is produced, distortions can be decreased at baseband signals. Conversion gain is achieved by mixing and amplification simultaneously. Mixer is designed to have wide band characteristics using distributed amplifier. In VCO design, Oscillator design method by large signal analysis is used to produce stable signal. Modulation/Demodulation system in baseband processor, DS/SS technique which is robust against noise and interference is used to eliminate the effect of multipath propagation. DQPSK modulation technique with M-sequences for wideband PN spreading signals is adopted because of BER characteristic and high speed digital signal transmission.

• Journal of Korean Society of Forest Science
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• v.107 no.2
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• pp.151-157
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• 2018

This study was to analyze the genetic diversity of Quercus gilva Blume growing in Jeju Island for developing a preservation strategy. We examined the genetic diversity and structure using 6 ISSR primers and investigated 67 polymorphic ISSR amplicons in 80 trees distributed among five populations. The average of proportion of polymorphic loci were 93%, the average level of Shannon's information index was 0.237, and Nei's genetic diversity was 0.156. According to the analysis of the molecular variance (AMOVA), $F_{st}$ was 0.169 indicating there was a genetic variation among five populations. 17% of the total variation was allocated among the five populations, while the other 83% of the total variation was in individual trees in each population. The result could be due to the uneven number of trees among the five populations. Based on these results, the preservation strategy could be developed, for examples, considering for designation as "forest genetic resources conservation area" about the habitat, monitoring continuously, fostering the growth of seedling, ex situ preservation of genetic resources, and comparing the differences of environmental and genetic characteristic with population in ex situ.

• Journal of the Korean Geophysical Society
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• v.3 no.1
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• pp.1-12
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• 2000

A palaeomagnetic study was carried out on Early through Late Cretaceous sandstones and volcanic sequences (the Songnaedong Formation, Chaeyaksan Volcanics, Konchonri Formation, and Jusasan Andesite it ascending order) from Konchonri area in the northern Milyang subbasin of the Kyongsang Basin, Korea. A high-temperature stable remanence with direction of $d=22.9^{\circ},\;i=59.1^{\circ}\;({\alpha}_{95}=3.0^{\circ})$ has been isolated and a corresponding pole was $71.6^{\circ}N,\;199.6^{\circ}E\;(A_{95}=4.2^{\circ})$. The characteristic high-temperature component resides in both hematite and magnetite. The primary nature of this remanence is confirmed from positive fold and reversals tests, The palaeopole is consistent with those of the Hayang Group in other parts of the Kyongsang Basin. A comparison of the palaeomagnetic pole position from the studied area with the contemporary pole from China west of the Tan-Lu fault presents that Konchonri area has experienced little latitudinal displacement nor vertical-axis block rotation relative to the Chinese blocks since the Cretaceous. Based on the formations indicating dual polarity, radiometric and paleontologic data, the magnetostratigraphic age of the studied sequence from the Songnedong Formation to the Jusasan Andesite ranges from upper Albian to lower Campanian reverse polarity chronozone. On the other hand, volcanic samples of the Chaeyaksan Volcanics and the Jusasan Andesite showed the scattered directions considered in group, even though individual sample showed a stable remanent magnetization in response to thermal demagnetization. It indicates that they have been reworked after acquisition of the stable remanent magnetization.

• Progress in Medical Physics
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• v.10 no.1
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• pp.23-32
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• 1999

Combined MRI and Relaxogram approach was introduced as a very useful tool for fat study. The phantoms simulating homogeneous mixture of fat and non-fat environments were measured with spin echo pulse sequence on a 0.15 T whole body imager. From 45 scans, the Tl values were obtained by fitting the data to continuous distribution (CONTIN) of relaxation time. This relaxogram gives broad distributions of relaxation time, which are characterized by a number of peaks with characteristic T1 values. Two distinct peaks in relaxogram were observed and identified as signals from com oil and gelatin gel. This model system can be served as simulating the distribution of fat in muscle. Also the relative ratio of two components, which is proportional to the area under the peak, is estimated and compared to nominal values. Based on the good agreement between two predictions, the values from our proposed method agreed with nominal values within $\pm$7 % error. The effects of different concentration of contrast agent and different region of interest are presented. To optimize total scan times, the minimum required data points and so further reduction in total scan times are discussed.

• The Journal of the Korea Contents Association
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• v.11 no.11
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• pp.111-119
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• 2011

Movie research in the 1980's structuralism looks tendency to escape director or text research and analyze spectator or inspection action. These post-structuralist divert interest by analytic convention of spectators in analysis by director's intention or text type correctly. There is the age that spectator, inspectional action and inspectional subject weighs more than director, work and text itself. But, inspection of movie can be person's enemy by director's narrative strategy or spectator's analytic quality that depend on a text and spectator and their interaction usually, and only method to acquire universality chooses full analytic discourse to principle. We should be structured by symbol system that the event is consisted of movie language to reappear the event through narrative in movie and this symbol system, director's narrative strategy can cause fixed esthetic distance between spectator. Researches to analyze this distance need to keep universal validity as much as being accepted by effort to gap with director and spectator. Therefore, narrative poetry that I analyze movie narration style by 'narrated' and unit of 'narrating' and study the form and function so-called, is going to follow narratology's access method. The consistent argument of this narrative poetry is that story is consisted of the events and these observe to structured thing by unit that is sequence through arrangement with the other event that adjoin in the event. Also, director need consensus with spectator to reappear connection of this event logically and it is thing which this reappearance form can be done characteristic by narrative strategy in directing. I am going to try narrative structure analysis of movie by narrative that is connected at structure of the event and 'narrating-narrative acts' that is interested in way to reappear this story to spectator hereupon. Of course, at process of research, Roland Barthes and his followers wish to apply 'narrative function' and concept of 'narrative acts' that prefer from time to time.

• Research in Plant Disease
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• v.23 no.1
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• pp.56-59
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• 2017

During growing season of 2011 to 2013, Sclerotinia rot symptoms consistently have been observed on basil in Yesan-gun, Chungcheongnam-do in Korea. The typical symptom formed initially brownish spot on leaf and stem, and then advancing margins, wilting the whole plant and blighting, eventually died. On the surface of diseased lesions was observed cottony, white, dense mat of mycelial growth, and sclerotia ($30-100{\mu}m$ diameter) formed on stem and leaf. Morphological and cultural characteristic on potato dextrose agar, color of colony was white and colorless chocolate, sclerotium of irregular shape of the oval was black and $5-50{\mu}m$ diameter in size. In pathogenicity test, necrosis and wilt of the inoculated stem were observed in all plants and the pathogen was reisolated from stems. On the basis of mycological characteristics, pathogenicity, and internal transcribed spacer rDNA sequence analysis, this fungus was identified as Sclerotinia sclerotiorum. This is the first report of Sclerotinia rot on basil caused by S. sclerotiorum in Korea.

• The Journal of the Korea Contents Association
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• v.11 no.5
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• pp.384-392
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• 2011

Recruitment and selection are separate but mutually reinforcing processes. The goal of recruitment is to attract the largest number of applicants possible to apply to the agency, and selection is the process of weeding out unqualified candidates and identifying qualified candidates. In this context, the recruitment and selection system of police officials is an important issue because it affects their future performance as police officers on the job, especially their policing skills, perception of society, occupational ethics. This study suggested the characteristics of U. S. recruitment and selection system of police officials. In the U. S, each police agency sets up its own recruitment and selection standards and procedures. However, recruitment and selection process follows a certain sequence : receiving application, psychological examination, background check, polygraph test, drug screening, interview, physical agility, and medical test. Special characteristic of American police system regarding recruitment and selection is that many law enforcement agencies use a polygraph test to ensure the integrity of the candidates. Another interesting screening process is a drug test because many Americans abuse illegal drugs. A candidate officer must submit urine or a hair sample for screening test. Police human resources specialists should continually identify the most innovative tests and approaches recruit and select police officers. Recruitment and selection strategies should increasingly attract and retain those officers who have the attributes to work in a community-oriented policing environment.

• Journal of Korean Society of Forest Science
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• v.102 no.1
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• pp.59-65
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• 2013

The jujube is an important fruit tree species in Korea. Traditionally, classifications of jujube cultivars have been based on morphological characters; however, morphological identification can be problematic because morphological traits are affected by environmental conditions. Therefore, DNA markers are now being used for the rapid and accurate identification of plant species. Inter-simple sequence repeat (I-SSR) is one of the best DNA-based molecular marker techniques, which is useful for studying genetic relations and for the identification of closely related cultivars. In this study, 5 Korean jujube trees and 1 jujube tree imported from China were analyzed for 16 I-SSR primers. Amplification of the genomic DNA of jujube cultivars by using I-SSR analysis generated 100 bands, with an average of 6.25 bands per primer, of which 45 bands (45%) were polymorphic. The number of amplified fragments with I-SSR primers ranged from 2 to 13. The percentage of polymorphism ranged from 10% to 100%. I-SSR finger printing profiles showed that 'Boeun jujube' and 'Daeri jujube' had characteristic DNA patterns, indicating unequivocal cultivar identification at molecular level. According to the results of clustering analysis, the genetic similarity coefficient ranged from 0.68 to 0.92. 'Boeun jujube' and 'Daeri jujube' were divided into independent groups, and 'Bokjo jujube', 'Geumseong jujube', 'Wolchul jujube', and 'Mudeung jujube' were placed in the same group. Therefore, I-SSR markers are suitable for the discrimination of 'Boeun jujube' and 'Daeri jujube' cultivars.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.39 no.6
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• pp.42-48
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• 2002

The design, construction and performance test of a convenient multi-purpose irradiator is described. A multi-purpose irradiator using Cesium-137 has been developed for studies of low dose radiation effects in biology and for calibration of Thermo Luminescent dosimeter(TLD). During the operation, three rods of radioactive material which are 10cm in length revolve 180 degrees and irradiate biological samples, or TLD, and return to their shielded position, after the programmed time. A programmable Logic Controller(PLC) controls the sequence of operation, interlock, motor rotation and safety system. The rotation speed of biological samples can vary up to 20 RPM. A real time monitoring system was also incorporated to check and control the operation status of the irradiator. The capacity of the irradiation chamber was 4.5 liters. The isodose distribution at arbitrary vertical planes was measured by using film dosimetry. The dose-rate was 0.13 cGy/min in air and 0.11 cGy/min in water equivalent material in the case of Cesium-137. Range of activity was 2 Ci. The homogeneity of dose distribution in the chamber was ${\pm}$7%. The actual radiation level on the surface was within permissible levels. The irradiator had a maximum 0.35 mR/min radiation leakage on its surface.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.7C
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• pp.675-686
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• 2005

In this paper, we propose an efficient face region detection technique for the content-based video summarization. To segment video, shot changes are detected from a video sequence and key frames are selected from the shots. We select one frame that has the least difference between neighboring frames in each shot. The proposed face detection algorithm detects face region from selected key frames. And then, we provide user with summarized frames included face region that has an important meaning in dramas or movies. Using Bayes classification rule and statistical characteristic of the skin pixels, face regions are detected in the frames. After skin detection, we adopt the projection method to segment an image(frame) into face region and non-face region. The segmented regions are candidates of the face object and they include many false detected regions. So, we design a classifier to minimize false lesion using CART. From SGLD matrices, we extract the textual feature values such as Inertial, Inverse Difference, and Correlation. As a result of our experiment, proposed face detection algorithm shows a good performance for the key frames with a complex and variant background. And our system provides key frames included the face region for user as video summarized information.