• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.4
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• pp.442-450
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• 2008

In this paper, the phase diverisity in a direct-conversion receiver for a UHF RFID reader is analyzed and the optimal I/Q signal combining methods is presented with respect to tag modulation. At first, fading characteristics of a single channel receiver is shown to prove the importance of phase diversity due to the phase relationship between the backscattered signal and the local oscillator. And the optimal signal combining methods are presented in order to overcome the signal power reduction due to phase diversity. In case of ASK, the power combining method is presented for the optimal I/Q combining. And the arctangent and principal component combining methods using covariance matrix of I and Q channels are presented for the optimal I/Q combining in case of PSK. In order to analyze the performance of suggested methods, the selection diversity and the optimal combining methods are compared. According to analysis and simulation results, the optimal combining methods have a maximum 3 dB SNR enhancement than selection diversity.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.2
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• pp.105-110
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• 2010

This study was conducted to analyze the relationships between resistance of brown planthopper and traits related to the lodging in rice. For the linkage analysis of traits tested in this study, a genetic linkage map was created with 162 DNA markers spanning 12 rice chromosomes based on 120 doubled haploid (DH) lines, which were derived from a cross between Samgang', a Tongil type cultivar with BPH resistance, and ‘Nagdong’, a japonica cultivar. QTLs were identified to analyze the agronomic traits including lodging by composite interval mapping. Thirteen QTLs were detected for five traits comprised of plant length (PL), 3rd internode length (3rdIL), moments (Mo), lodging index (LI), and breaking weight (BW). The relationships between the BPH resistance and agronomic traits including lodging revealed that two QTLs (qBPR7, qBPR8) were linked to traits related to lodging. Two QTLs, qBPR7 and qBPR8 on chromosome 7 (RM531-7042) and 8 (RM1148- RM544) showed associations with moments and 3rd internode length, respectively.

• Korean Journal of Optics and Photonics
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• v.31 no.6
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• pp.328-333
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• 2020

In this paper, we study the analysis method for the aspherical tolerance of a Korsch telescope using a Q polynomial. It is important to analyze the tolerances for evaluating quality in high-precision fabrication of aspherical reflectors for high-resolution satellites. Thus we express the aspheric surface in terms of a Q polynomial in which each coefficient term is composed independently, and analyze the tolerance of a Korsch telescope. We also analyze the tolerance using Zernike fringe sag, which expresses the shape error of an aspherical mirror. By comparing the two results, we confirm that the Q-polynomial method can be used to analyze an aspherical mirror.

• Asia Marketing Journal
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• v.1 no.3
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• pp.120-140
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• 1999

Q 방법은 인간의 태도와 행동을 연구하기 위해 철학적, 심리학적, 통계적, 그리고 심리측정과 관련된 개념을 통합한 방법론으로서 인간의 주관성을 정량적으로 분석할 수 있는 특수한 통계기법이다. 소비자의 인식, 가치, 태도, 신념과 같은 개념을 객관적으로 연구할 수 있는 방법으로서 가설 생성을 위한 탐색적 연구와 이론의 검증과 같은 확인적 연구에서도 적용될 수 있다. 많은 수의 표본을 대상으로 한 횡단적 R 방법에 비하여 개인이나 소집단에 대한 깊이 있는 탐구가 가능하다는 점에서 소비자 행동 연구에 유용성이 매우 높다. 개인의 주관성을 바탕으로 한 소비자 개인의 특성과 차별성을 이해하는 것이 마케팅 분야의 핵심을 이루고 있음에도 불구하고 그 동안 소비자의 주관성에 대한 깊이 있는 접근이 이루어지지 못하였다. 1935년에 심리학 분야에서 개발된 Q방법은 이를 분석할 수 있는 컴퓨터 패키지의 보급과 더불어 사회과학 전반에 걸쳐 그 활용이 확산되어 가고 있다. 이에 Q 방법의 과학철학적 특성과, 현재 널리 이용되고 있는 변수 중심의 R 방법과의 차이, 그리고 컴퓨터 분석을 포함한 구체적인 Q 분석방법 및 관리적 활용상의 문제점에 대해 논의하였다

• The Korean Journal of Ecology
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• v.17 no.3
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• pp.241-249
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• 1994

Leaf diffusive resistance (LDR), stomatal density, length of guard cell and hair density of leaves of 6 oak species were determined under withdrawal of water, and their strategies of drought stress were analyzed by principal component analysis. LDR of Quercus acutissima, Q. aliena and Q. serrata increased earlier than those of the other species at high leaf water potential $({\Psi}_{leaf})$ or low water saturation deficit (WSD), which was an avoidance mechanism reducing damage by water stress. Q. variabilis with low stomatal density, small stomatal size and high hair density had avoidance mechanisms increasing LDR at high $({\Psi}_{leaf})$ However, Q. mongolica and Q. dentata increased LDR at low $({\Psi}_{leaf})$ as xeric species do. Results from principal component analysis on the 15 variables related to strategies of drought stress indicated that the 6 oak species were divided into 2 groups: (1) Q. acutissima, Q. aliena and Q. serrata as mesic habitat species and (2) Q. variabilis, Q. mongolica and Q. dentata as xeric habitat species. Among three xeric species Q. acutissima differed from the other two species in the drought strategies such as high hair density, low stornatal density, high leaf area ratio, stomatal closing at low $({\Psi}_{leaf})$ and small cell wall elasticity. The results could reasonably explain their drought strategies in natural habitat.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.10
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• pp.46-53
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• 2016

The purpose of this study is to analyze the cognizance of AIDS by applying the Q methodology, as well as to provide preliminary data for developing AIDS prevention campaigns. A Q population was identified from a literature search and in-depth interviews. The study process analyzed the P sample, the study participants, using the Q-sorting methodology to produce the Q sample, which is composed of statements from October 20 to 27, 2014. 20 participants (analyzed) 27 statements and 3 types of AIDS cognizance were produced as a result. These types are 1(N=9), 2(N=6), and 3(N=5), which correspond to denial, social support, and selfish motivation, respectively. The members of the denial type had a strongly negative opinion about AIDS, whereas the social support type showed a friendly gesture. The selfish motivation type took a neutral stance. The common and different points, as well as the distinctive features of these types, were studied. The accomplishments of this study include suggesting an efficient strategy for making an AIDS control policy, as well as a qualitative analysis, through the employment of the Q-methodology, which is useful for understanding human beings' (internal viewpoint).

• Korean Journal of Plant Taxonomy
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• v.35 no.1
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• pp.57-80
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• 2005

Morphological variation of Quercus L. subgen. Quercus in Korea was examined by numerical methods including principal components analysis of major morphological characters. Principal components analysis revealed the presence of five major species groups of the subgen. Quercus in Korea; these include 1) a group consisiting of Q. acutissima and Q. variabilis individuals, 2) Q. dentata, 3) Q. aliena, 4) Q. mongolica, and 5) Q. serrata. The putative interspecific hybrid individuals occupied intermediate position between the putative parent species in the PCA plot. The analysis also strongly suggested that size and shape of leaf blade and teeth or lobes, twig diameter, size and shape of nuts, and length and width of scales are very useful in distinguishing the species and the putative hybrids of the subgen. Quercus.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.05a
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• pp.529-531
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• 2011

In Gen-2 Q-algorithm, the values of weight C, which is the parameter for incrementing or decrementing the slot-count size, are not defined in the standard. In this case, if the reader selects an inappropriate weight, there are a lot of empty or collided slots. As a result, the performance will be degraded because the frame size does not converge to the optimal point quickly during the query round. In this paper, we analyze how the performances of Gen-2 Q-algorithm will be affected by the weight value.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.10
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• pp.1940-1946
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• 2015

An optical coherent system is considered for the next-generation optical access networks in enhancing the data rate and transmission distance. In this system, however, I/Q amplitude imbalance may occur at several parts of the system, leading to serious performance degradation. Asymmetric structure of a coherent receiver at the location of subscriber is one of the sources of I/Q imbalance. Therefore, this imbalance parameters must be removed or compensated to secure the transmission performance. In this paper, the source of I/Q amplitude imbalance is analyzed, and then the way to compensate for the imbalance at the receiver side is suggested. Performance after the compensation is estimated using simulation.

• Proceedings of the Korea Contents Association Conference
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• 2011.05a
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• pp.431-432
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• 2011

본 연구는 고등교육기관으로서 국가의 발전과 산업인재양성에 중요한 역할을 수행하고 있는 전문대학의 속성 유형을 Q-방법론을 적용하여 조사 분석하여 전문대학에 대학 인식유형을 분류하고 유형간 차이를 분석하고자 한다.