• 식물분류학회지
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• 제37권4호
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• pp.323-333
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• 2007

The degree to which parallel evolution utilizes the same genetic mechanisms indicates the degree to which developmental processes constrain or channel phenotypic evolution. A transgenetic strategy was used to elucidate the role of one floral meristem identity gene, LEAFY (LFY), in the evolution of rosette flowering, a plant architecture that has evolved in parallel in several lineages of the mustard family, Brassicaceae. The LFY genes from three rosette flowering species were cloned and introduced into a species with the ancestral architecture, and results indicated that changes at the LFY locus contributed to the evolution of rosette flowering in two of the three lineages, but that in each lineage a different set of genetic partners was involved. Also, LFY was shown to play a role in the evolution of flower size. Transgenetic strategy may be useful in the study of plant morphological evolution and parallelism.

• 한국대기환경학회지
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• 제12권3호
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• pp.307-314
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• 1996

The rate of evolution of ethylent by tomato plants was rapidly increased by ozone fumigation. In the present study, the mechanism of ethylent evolution by ozone was investigated in experiments with aminoethoxyvinylglycine (AVG) and tiron, which inhibit the formation of ethylene and peroxidation of lipids, respectively. Pretreatment with AVG significantly inhibited the ozone-induced ethylent evolution, but the treatment of plants with tiron did not inhibit. These results indicate that the induction of the evolution of ethylene by ozone involves the pathway via aminocyclopropane-1-carboxylate (ACC), while not released as a result of the peroxidation of lipids. Ozone-induced ethylent evolution was greater in dar- than light-incubated, intact tomato plants. The difference between dark- and light-ethylene evolution was examined with diuron, an inhibitor of photosynthetic electron transport. The inhibitor treatment promoted ethylent evolution. These results suggest that ethylent retention and metabolism in plants were regulated by internal $CO_2$ levels which, in turn, were controlled in large part by photosynthesis. Thus, ethylene was retained in illuminated leaf tissue under low intenal $CO_2$ concentration which may develop in a sealed container without exogenously supplied $CO_2$.

• 한국대기환경학회지
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• 제12권3호
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• pp.333-340
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• 1996

The relationship between ozone-induced damages and ethylend evolution was examined in tomato plants fumigated with ozone of 0.2 $\mu\ell/\ell$. The rate of evolution of ethylent by tomato plants was enhanced by ozone fumigation. Pretreatment of leaves with aminoethoxyvinylglycine (AVG), an inhibitor of ethylene evolution, significantly inhibited the evolution of ethylene that was induced by ozone and concomitantly reduced the extent of ozone-induced visible damage to leaves. Treatment with 2,5-norbonadiene (NBD), and inhibitor of the action of ethylene, strongly reduced the extent of visible damage caused by ozone, even though it did not suppress the evolution of ethylene. These results indicated that ethylene might play an important role in ozone-induced plant injuries at relatively short terms of ozone fumigation. Next, we examined the effect of tiron, a scanvenger of the free-radical, on evolution of ethylene and leaf injury caused by ozone. Tiron treatment strongly reduced the extent of ozone-induced injury, but had not inhibitory effect on the evolution of ethylene from tomato leaves. This result suggests the involvement of free-radical, such as superoxide radicals, in induction of injuries caused by ozone.

• 한국정밀공학회지
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• 제21권5호
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• pp.188-202
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• 2004

This research was designed to investigate biomechanical aspects of the evolution based on the hypothesis of dynamic cooperative interactions between the locomotion pattern and the body shape in the evolution of human bipedal walking The musculoskeletal model used in the computer simulation consisted of 12 rigid segments and 26 muscles. The nervous system was represented by 18 rhythmic pattern generators. The genetic algorithm was employed based on the natural selection theory to represent the evolutionary mechanism. Evolutionary strategy was assumed to minimize the cost function that is weighted sum of the energy consumption, the muscular fatigue and the load on the skeletal system. The simulation results showed that repeated manipulations of the genetic algorithm resulted in the change of body shape and locomotion pattern from those of chimpanzee to those of human. It was suggested that improving locomotive efficiency and the load on the musculoskeletal system are feasible factors driving the evolution of the human body shape and the bipedal locomotion pattern. The hypothetical evolution method employed in this study can be a new powerful tool for investigation of the evolution process.

• 한국IT서비스학회:학술대회논문집
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• 한국IT서비스학회 2006년도 추계학술대회
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• pp.593-599
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• 2006

Including technical device and general information system, the information-technical(IT) system is defined as the technical system for acquiring, processing, storing and transferring information to a person. This paper presents Knowledge-based Heuristic Evolution Model for creating the advanced information-technical system. This Evolution Model is derived from the historical review on definition of evolution, the research on the architecture of the general IT system, history of IT system, technology innovation theory and multi-case study research. The evolution model is applicable to the conceptual creation of the advanced product in R&D organization requiring development methodologies like rapid-prototyping to develop next generation product. For the detailed theoretical construction and practical application of Evolution Model, the case study research based on action research is performed. the object of the case study is mobile device, especially mobile hand-held phone. Thus, we obtain the Evolution Model for creating the advanced information-technical system.

• 대한수학회논문집
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• 제36권4호
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• pp.759-770
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• 2021

The purpose of this paper is to prove unique existence of bounded solution and periodic solution to inhomogeneous linear evolution equations which trajectories of these solutions belong to given admissible Banach function space.

• 한국과학교육학회지
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• 제37권4호
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• pp.747-761
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• 2017

이 연구는 생명 과학 교수 실행에 있어서 진화 교육 연구 경험이 있는 교사가 그렇지 않은 교사와 어떤 차이를 나타내는지 알아보기 위해 수행되었다. 연구를 위해 진화 교육에 대한 연구 경험이 있는 교사 두 명과 이에 대한 비교집단으로 진화 교육에 대한 연구 경험이 없는 교사 두 명, 총 네 명의 생명과학 교사들을 목적 표집하였다. 먼저, 사전면담을 통해 교사들의 배경지식을 수집하였으며, 생명과학 수업 중 진화 단원과 비진화 단원을 각각 2차시씩 선정하였다. 녹음된 수업은 전사하였으며, 교사들의 진화에 대한 견해 및 교수 실행에 반영된 진화 내용을 중심으로 분석하였다. 또한, 연구를 위한 기초자료로 과학 교수내용지식 설문지, 진화론의 개념 검사지, 진화론의 수용 검사지를 사용하여 자료수집 및 분석 하였다. 연구결과 교사들의 진화 개념에 대한 이해 수준은 진화의 중요성 인식과는 관련이 없는 것으로 나타났다. 다만, 교사 개인의 종교적인 신념이나, 진화의 중요성을 인식하는 것에 대한 필요 자체를 느끼지 못함이 진화의 중요성 인식에 부정적인 영향을 미쳤다. 이 때문에 진화교육 연구 미경험 교사들은 진화의 중요성을 인식할 수 있는 교사 재교육 기회도 거부하는 경향을 보였다. 또한 미경험 교사들은 교과서 및 교육과정에서 나타난 진화 개선점에 대해 피상적으로만 파악하고 있었다. 생명과학 교수 실행 내용을 분석한 결과 경험 교사들의 진화 주요 개념 활용 비율이 더 높게 나타났다. 그리고 경험 교사들만이 자신의 교수 실행에서 나타난 오개념을 스스로 인지하고 이러한 오개념이 나타나게 된 원인에 대해 설명을 했다. 이를 통해 진화 교육 연구 경험 교사가 진화 주요 개념들을 폭넓게 활용할 뿐만 아니라 진화 관련 오개념 방지에 더 실천적임을 확인하였다. 연구 결과는 생물 교육에서 진화의 중요성을 깨닫지 못한 교사들에게 좀 더 다양하고 많은 진화 관련 교사교육 프로그램을 제공할 필요성을 알려준다.

• 천문학회보
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• 제38권2호
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• pp.59.1-59.1
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• 2013

Type Ia supernovae (SNe) are providing the most conclusive evidence for accelerating universe with dark energy in observational cosmology. In these investigations, look-back time evolution of SNe luminosity is regarded as negligible on the basic assumption. However, several recent works present some systematic differences among hosts which have different characteristics of stellar population. For more direct investigation, we are proceeding with our YONSEI (YOnsei Nearby Supernovae Evolution Investigation) project. Only early-type hosts in our catalogue were chosen in order to estimate the luminosity-weighted mean age and metallicity directly using Single Stellar Population (SSP) models and ignore the effect from the dust extinction. Observations using low-resolution spectrographs are still in progress at Las Campanas Observatory with 2.5m telescope and at McDonald Observatory with 2.7m telescope. We have thus far obtained spectra for 30 early-type hosts. After weak emission line correction, Lick/IDS absorption-line indices are measured and YEPS spectroscopic evolution model was applied to determine mean population ages and metallicities. Our preliminary results show that SNe Ia hosted in older galaxies seem to be brighter at 1.4 - 3 sigma levels, however, more observations and analyses are still needed to confirm this correlation.

• Journal of Information Processing Systems
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• 제15권6호
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• pp.1422-1437
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• 2019

With the rapid development of the Internet and the Mobile Internet, social communication based on the network has become a life style for many people. WeChat is an online social platform, for about one billion users, therefore, it is meaningful to study the spreading and evolution mechanism of the rumor on the WeChat social circle. The Rumor was injected into the WeChat social circle by certain individuals, and the communication and the evolution occur among the nodes within the circle; after the refuting-rumor-information injected into the circle, subsequently,the density of four types of nodes, including the Susceptible, the Latent, the Infective, and the Recovery changes, which results in evolving the WeChat social circle system. In the study, the evolution characteristics of the four node types are analyzed, through construction of the evolution equation. The evolution process of the rumor injection and the refuting-rumor-information injection is simulated through the structure of the virtual social network, and the evolution laws of the four states are depicted by figures. The significant results from this study suggest that the spreading and evolving of the rumors are closely related to the nodes degree on the WeChat social circle.

• 한국과학교육학회지
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• 제32권10호
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• pp.1537-1550
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• 2012

이 연구 목적은 한국과 미국 대학생들을 대상으로 진화 개념과 관련된 변인-종교성, 진화 흥미, 진화 개념, 진화 수용-에 관한 수준과 구조적 차이를 비교 분석하는 것이다. 이 연구를 위하여 한국과 미국 대학생 1,015 학생이 참여하였으며 그 중 무작위로 추출된 516명의 자료가 분석에 활용되었다. 연구 결과 한국의 대학생들은 미국의 대학생들에 비하여 낮은 종교성을 보이는 반면 진화 흥미 역시 낮았다. 경로 분석결과 종교성이 진화 수용에 미치는 인과관계에서 진화 개념과 진화 흥미가 매개함을 알 수 있었다. 한국 대학생들은 미국 대학생들에 비하여 진화 흥미가 종교성, 진화 수용, 진화 개념과 상대적으로 낮은 수준의 관련성을 보였다. 한국의 생물 전공자들의 진화 수용은 미국 생물 전공자들의 비하여 진화 개념에 대한 영향력이 적었고, 한국 생물 비전공자들의 진화 수용은 미국 생물 비전공자들에 비하여 종교성에 더 큰 영향을 받았다. 이 연구 결과는 한국 학생들을 위한 진화 교육이 진화론에 대한 흥미를 더 높이며, 진화론을 수용함에 있어 개인의 종교적 신념에 근거하지 않고 과학적 이론으로 수용할 수 있어야 함을 보여준다. 또한 우리나라 대학생들이 과학적 판단에 의하여 과학 이론을 수용하는 태도를 함양시킬 수 있는 과학교육이 필요하다.