• 한국통신학회논문지
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• 제36권9B호
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• pp.1092-1097
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• 2011

An anti-collision protocol which tries to minimize the collision probability and identification time is the most important factor in all identification technologies. This paper focuses on methods to improve the efficiency of tag's process in identification systems. Our scheme, Binary Slotted Query Tree (BSQT) algorithm, is a memoryless protocol that identifies an object's ID more efficiently by removing the unnecessary prefixes of the traditional Query Tree (QT) algorithm. With enhanced QT algorithm, the reader will broadcast 1 bit and wait the response from the tags but the difference in this scheme is the reader will listen in 2 slots (slot 1 is for 0 bit Tags and slot 2 is for 1 bit Tags). Base on the responses the reader will decide next broadcasted bit. This will help for the reader to remove some unnecessary broadcasted bits which no tags will response. Numerical and simulation results show that the proposed scheme decreases the tag identification time by reducing the overall number of request.

• 응용통계연구
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• 제30권5호
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• pp.793-808
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• 2017

본 논문에서는 초고차원 자료의 다항분류를 위한 변수선별 방법에 대해 비교 연구를 진행하였다. 다항분류를 위한 변수선별 방법에는 일대일 혹은 일대다 비교를 통해 이항분류를 위한 방법을 확장시켜 적용하는 방법과 다항 반응 변수에 직접 적용할 수 있는 방법이 있다. 다항분류를 위한 변수선별 성능을 확인하기 위하여 여러가지 상황-설명변수의 꼬리가 두꺼운 경우, 신호변수와 잡음변수가 서로 연관된 경우, 결합분포상으로 연관되어 있지만 주변분포 상으로는 연관되어 있지 않은 경우, 다범주 반응변수의 분포가 불균형인 경우-을 가정하고 모의실험을 진행하였고, 실제 자료에도 적용해 보았다. 그 결과, 모형 가정을 필요로 하지 않는 방법들이 안정적인 성능을 보이는 것을 확인하였다.

• Communications for Statistical Applications and Methods
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• 제25권3호
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• pp.321-328
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• 2018

In clinical trials with repeated measurements, the time-averaged difference (TAD) may provide a more powerful evaluation of treatment efficacy than the rate of changes over time when the treatment effect has rapid onset and repeated measurements continue across an extended period after a maximum effect is achieved (Overall and Doyle, Controlled Clinical Trials, 15, 100-123, 1994). The sample size formula has been investigated by many researchers for the evaluation of TAD in two treatment groups. For the evaluation of TAD in multi-arm trials, Zhang and Ahn (Computational Statistics & Data Analysis, 58, 283-291, 2013) and Lou et al. (Communications in Statistics-Theory and Methods, 46, 11204-11213, 2017b) developed the sample size formulas for continuous outcomes and count outcomes, respectively. In this paper, we derive a sample size formula to evaluate the TAD of the repeated binary outcomes in multi-arm trials using the generalized estimating equation approach. This proposed sample size formula accounts for various correlation structures and missing patterns (including a mixture of independent missing and monotone missing patterns) that are frequently encountered by practitioners in clinical trials. We conduct simulation studies to assess the performance of the proposed sample size formula under a wide range of design parameters. The results show that the empirical powers and the empirical Type I errors are close to nominal levels. We illustrate our proposed method using a clinical trial example.

• 한국통신학회논문지
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• 제31권11A호
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• pp.1130-1137
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• 2006

다수의 MD 태그들로부터 발신된 메시지들 사이의 충돌을 빠르게 해소하는 일은 대규모 RFID 시스템의 성능을 결정짓는 중요한 문제이다. 본 논문에서는 충돌방지 (anti-collision) 알고리즘의 성능 향상을 위하여 다중 패킷 수신 (multi-packet reception) 기법을 사용할 것을 제안한다. 다중 패킷 수신 기법을 통해서 RFID 판독기는 동시에 전송된 다수의 태그를 충돌없이 수신 할 수 있다. 대표적인 충돌방지기법인 이진 트리 분리 (binary-tree-splitting) 알고리즘과 슬롯 알로하 (Slotted-Aloha) 알고리즘에 다중 패킷 수신 기법을 적용했을 경우의 성능향상을 분석하는 모델을 제안하고 제안된 분석모델의 정확성을 시뮬레이션을 통해서 비교 검증한다. 다중 패킷 수신기법 적용 시 큰 폭의 성능향상이 있음을 보이고, 다중 패킷 수신 기법의 이득을 최대화하기 위해서는 RFID 판독기 안테나 디자인과 수신 신호 분리 기술이 중요함을 보인다.

• 한국산학기술학회논문지
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• 제20권6호
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• pp.541-547
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• 2019

최근 자동화 되는 해킹 및 분석 기술의 발전으로 인하여 수많은 소프트웨어 보안 취약점이 빠르게 발표되고 있다. 대표적인 취약점 데이터베이스인 NVD(National Vulnerability Database)에는 2010년부터 2015년까지 보안 취약점(CVE: Common Vulnerability Enumeration) 약 8만 건이 등록되었으며, 최근에도 점차 증가하고 있는 추세이다. 보안 취약점은 빠른 속도로 증가하고 있는 반면, 보안 취약점을 분석하고 대응하는 방법은 전문가의 수동 분석에 의존하고 있어 대응 속도가 느리다. 이런 문제점을 해결하기 위해 자동화된 방법으로 보안 취약점을 탐색하고, 패치하여 악의적인 공격자에게 공격 기회를 줄 수 있는 보안 취약점을 사전에 대응 할 수 있는 기술이 필요하다. 본 논문에서는 복잡도 분석을 통해 취약점 탐색 대상 바이너리의 특징을 추출하고, 특징에 적합한 취약점 탐색 전략을 선정하여 취약점을 자동으로 탐색하는 기술을 제안한다. 제안 기술은 AFL, ANGR, Driller 도구와 비교 검증 하였으며 코드 커버리지는 약 6% 향상, 크래시 개수는 약 2.4배 증가, 크래시 발생율 약 11% 향상 효과를 볼 수 있었다.

• 영어영문학
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• 제57권6호
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• pp.1111-1130
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• 2011

Reading postmodern texts certainly situates readers in roles different from the ones we have been used to. Recently, postmodern metafiction forms a significant body of children's literature that is intended to challenge and transform the conventions of books in the digital age. While many studies have been done as to how child readers have capabilities to appreciate and interpret postmodern metafiction picture books, few studies on teachers and preservice teachers' reactions are not readily available. The role of teachers and preservice teachers are crucial for child readers to have access to affluent reading resources. This study discusses how preservice teachers read and respond to postmodern metafiction picture books using a deconstructive approach by means of binary opposites. Data was collected with 14 preservice teachers as to their likes/dislikes, reading levels, and reading paths about postmodern metafiction picture books. Expected pedagogical implications for literacy and language education were requested to address in their reading diaries and response papers. With their likes/ dislikes, since binary opposites always imply the hierarchy of power and value, the likes is apparently more valued and appreciated over their dislikes. This differentiated values are discussed in more detail with three recurring themes-Education, Morals and Behavior, and Tradition. With reading levels, there seems to be a gap existing between the authors' implied reader and literary critics' and the preservice teachers' ideal readers for the postmodern metafiction picture books. Although many studies have already revealed young readers' capability of appreciating postmodern metafiction, it depends a lot more on the teachers and preservice teachers whether children's right to have access to affluent literacy resources is respected or not. Preservice teachers' awareness of the potential of postmodern metafiction will work as an initial step to bring and realize the new reading path and new literacies in classrooms. By challenging metanarratives of children's literature, preservice teachers' readings of postmodern picture books reveals potentials to raise different reading paths and develop new literacies and other educational implications.

• ETRI Journal
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• 제35권6호
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• pp.1105-1114
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• 2013

Owing to the large number of video programs available, a method for accessing preferred videos efficiently through personalized video summaries and clips is needed. The automatic recognition of user states when viewing a video is essential for extracting meaningful video segments. Although there have been many studies on emotion recognition using various user responses, electroencephalogram (EEG)-based research on preference recognition of videos is at its very early stages. This paper proposes classification models based on linear and nonlinear classifiers using EEG features of band power (BP) values and asymmetry scores for four preference classes. As a result, the quadratic-discriminant-analysis-based model using BP features achieves a classification accuracy of 97.39% (${\pm}0.73%$), and the models based on the other nonlinear classifiers using the BP features achieve an accuracy of over 96%, which is superior to that of previous work only for binary preference classification. The result proves that the proposed approach is sufficient for employment in personalized video segmentation with high accuracy and classification power.

• Molecules and Cells
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• 제46권7호
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• pp.451-460
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• 2023

Animals generally prefer nutrients and avoid toxic and harmful chemicals. Recent behavioral and physiological studies have identified that sweet-sensing gustatory receptor neurons (GRNs) in Drosophila melanogaster mediate appetitive behaviors toward fatty acids. Sweet-sensing GRN activation requires the function of the ionotropic receptors IR25a, IR56d, and IR76b, as well as the gustatory receptor GR64e. However, we reveal that hexanoic acid (HA) is toxic rather than nutritious to D. melanogaster. HA is one of the major components of the fruit Morinda citrifolia (noni). Thus, we analyzed the gustatory responses to one of major noni fatty acids, HA, via electrophysiology and proboscis extension response (PER) assay. Electrophysiological tests show this is reminiscent of arginine-mediated neuronal responses. Here, we determined that a low concentration of HA induced attraction, which was mediated by sweet-sensing GRNs, and a high concentration of HA induced aversion, which was mediated by bitter-sensing GRNs. We also demonstrated that a low concentration of HA elicits attraction mainly mediated by GR64d and IR56d expressed by sweet-sensing GRNs, but a high concentration of HA activates three gustatory receptors (GR32a, GR33a, and GR66a) expressed by bitter-sensing GRNs. The mechanism of sensing HA is biphasic in a dose dependent manner. Furthermore, HA inhibit sugar-mediated activation like other bitter compounds. Taken together, we discovered a binary HA-sensing mechanism that may be evolutionarily meaningful in the foraging niche of insects.

• 한국과학교육학회지
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• 제14권2호
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• pp.123-132
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• 1994

The experimental evidence evaluation of the 11th grade students(N:91) was investigated. Specially, the influence of students' ideas about optical phenomena and presented evidence types on their evidence evaluation, and the influence of students' ideas on their causal inference modes were investigated. After eliciting the students' ideas about shadow phenomena and conformity of their idea, the experimental results with a binary outcome were presented as the evidence. Then the students were asked to evaluate the evidence. Again students' ideas were elicited. Most of students had causal ideas such that the shape of object(96%) and the inclination of screen(75%) were causes of shadow shape, not the shape(70%) and color(92%) of light source. In the case of the shape of object and the color of light source, most students(70%) believed strongly their ideas. Most responses(80%) in the evidence were evidence-based, and 12% of them were theory-based. There was no significant difference of reponses types between students with causal ideas(81%) and students with non-causal ideas(78%), between covariable and non-covariable evidence. But in the case of non-causal ideas, covariable evidence was more likely to yield evidence-based reponses than non-covariable evidence. If students had preconcepts inconsistent(84%) with the evidence, they were more likely to make evidence-based responses than the students with consistent ideas (75%) with the evidence. Especially in the case perceptually biased evidence, this tendency was marked. In the case of covariable evidence, many students made inclusion inferences(40%) rather than uncertainty inferences(32%). In the case of uncertainty inferences(94%), students more likely to make evidence-based reponses than inclusion inferences(83%) and exclusion infernces(88%). In the case of inclusion inferences and exclusion infernces, students tended to make idea-based responses and distort the evidences. In conclusion, when the students evaluate the experimental evidences, their ideas influence the causal inference modes. Especially, according to the conformity of the preconcepts and logical relation of evidences, the inference modes are more strongly depended upon the preconcepts rather than evidences.

• 한국식물병리학회지
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• 제11권4호
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• pp.374-379
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• 1995

The cDNA of tobacco mosaic virus-pepper strain (TMV-P) coat protein (CP) genes were introduced into tobacco plants (Nicotiana tabacum cv. Samsun nn) using a binary Ti plasmid vector of Agrobacterium tumefaciens. these cDNAs introduced into tobacco plants were detected by polymerase chain reaction. Symptom development was distinctly suppressed in the transgenic plant introduced buy sense CP cDNA when the plant was inoculated with TMV-P, while in transgenic tobacco plants of antisense CP gene, symptom development was not suppressed as in non-transgenic plants. TMV-P concentration in the sense CP transgenic tobacco plant was decreased to 1/14 of the concentration in non-transgenic plants. Expression of the kanamycin resistance gene of these transgenic plants could be detected in the progeny.