• Title/Summary/Keyword: 부류

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Morphology and Reproduction of Symphyocladia latiuscula (Harvey) Yamada (Rhodophyta, Rhodomelaceae) in Korea (한국산 홍조 참보라색우무(Symphyocladia latiuscula (Harvey) Yamada)의 형태와 생식)

  • 최도성
    • Journal of Plant Biology
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    • v.34 no.1
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    • pp.59-66
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    • 1991
  • The morphotaxonomic characters and life history of Symphyocladia latiuscula (Harvey) Yamada were investigated with field and laboratory culture materials. The species is well defined by a 5-15 cm hight, entirely corticated thallus and congenital fusion of 5-7 segments between main axis and laterals. Although all the reproductive structures are basically similar to those of other species of the genus, it is characteristic that the pinnulae are transformed into the flabellated tetrasporangial stichidia. Vegetative trichoblasts are known to be absent in the Pterosiphonieae, but their presence in S latiuscula does not accept its taxonomic position in that tribe. As a result, the occurrence of vegetative trichoblast is not useful for a taxonomic character to distinguish the tribes. The species shows a Polysiphonia-type life history involving a dimorphic alternation of gametophytes and sporophytes in culture and field. It grows below the middle intertidal zone in all the coasts of Korea throughout the year, although fertile plants are normally found during the summer months.months.

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Developing and Evaluating the Fixture of Vibration Test for a Large Equipment (대형장비의 진동시험치구 개발 및 실험적 평가)

  • 윤용집;최창하;기무현;오승종
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 1995.10a
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    • pp.296-304
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    • 1995
  • 환경시험의 일부인 진동시험은 그 결과를 가지고 장비가 실제 운용하기 전에 진동에 대한 내구성이 있는가를 판단할 수 있는 단 하나의 방법이다. 이런 진동시험을 성공적으로 이끌어 정확한 결론에 도달하기 위해서는 아래 두 가지 문제에 대한 해결이 필수적이라고 생각한다. 첫번째는 '실제 상황을 정확히 반영할 수 있는 진동시험수준의 결정이다.' 진동시험수준이 적절하지 못하면 전체적으로나 부분적으로 과대진동시험(Overtest)을 실시하거나, 과소진동시험(Undertest)을 실시할 수 밖에 없고, 이에 따른 결과도 신뢰도가 떨어진다. 예를 들어, 과대진동시험으로 시험장비가 고장나거나, 과소진동시험으로 시험장비에 이상이 없다고 해서 실제 상황에서 이 장비가 진동에 대하여 만족할 만한 내구성을 갖는다고 누구도 말할 수 없기 때문이다. 두번째는 '정해진 진동시험수준을 진동시험기로부터 시험장비에 얼마나 정확히 전달할 수 있는가?'라는 문제이다. 실제로 원하는 진동시험수준을 한치의 오차없이 정확히 시험장비에 가하는 것은 거의 불가능하다. 특히 시험장비가 대형화 되면 될수록 문제는 더 심각하다. 결론적으로 위에 지적한 두가지 문제의 해결이 성공적인 진동시험의 열쇠이며, 또한 시험결과에 대한 신뢰성을 보장받을 수 있는 길이기 때문이다. 이번 논문에서 다루고자 하는 것은 두번째 문제인 진동시험수준의 정확한 전달을 위하여 진동시험기와 시험장비 사이를 연결해 주는 진동시험치구(Test Fixture) 개발에 관한 것이다. 실제 개발한 치구는 미군사규격(Military-Standard)과 보잉사 규격(Boeing specification) 그리고 샌디아사 규격(Sandia Corporation Standard)에 근거하여 분류하는 분류기준표에서 치구 중 가장 큰 부류(500 pounds 이상)에 속는 것으로, 현재 우리나라에서 보유하고 있는 것 중에 용량이 가장 큰 진동시험기에서 진동시험을 준비하고 있는, 체계에 전원을 공급하는 대형장비의 치구이다. 또한 실 진동시험을 실시하기 전의 모달시험과 예비시험 그리고 실 시험결과를 기술하므로써 제작된 치구의 실험적 평가를 하고자 한다.

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Recognition of Unconstrained Handwtitten Numerals Based on Modular Design and Pipeline Connection (모듈러 설계 및 파이프라인 연결에 기반한 무제약 필기 숫자의 인식)

  • Oh, Il-Seok;Choi, Soon-Man;Hong, Ki-Cheon;Lee, Jin-Seon
    • Korean Journal of Cognitive Science
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    • v.7 no.1
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    • pp.75-84
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    • 1996
  • In this paper we emphasize the importance of architectural aspects of designing a handwritten numeral recognition program. and describe two architectural design.First, we describe the modular design of a numeral recognition program, and mention its advantages.In this design, a recognizer is composed of 10 binary subrecognizers each of which is responsible for only one class.Rule-based training and neural-based training are presented.Second, we connect two(or more)recognizers serially which we call pipelining connection.The second recognizer may act as verifier for the patterns recognized by the forst recognizer, or as second chance recognizer for the patterns rejected by the first recognizer.Our experimental results obtained till now show the merits of the proposed architectural designs.

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A Fingerprint Classification Method Based on the Combination of Gray Level Co-Occurrence Matrix and Wavelet Features (명암도 동시발생 행렬과 웨이블릿 특징 조합에 기반한 지문 분류 방법)

  • Kang, Seung-Ho
    • Journal of Korea Multimedia Society
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    • v.16 no.7
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    • pp.870-878
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    • 2013
  • In this paper, we propose a novel fingerprint classification method to enhance the accuracy and efficiency of the fingerprint identification system, one of biometrics systems. According to the previous researches, fingerprints can be categorized into the several patterns based on their pattern of ridges and valleys. After construction of fingerprint database based on their patters, fingerprint classification approach can help to accelerate the fingerprint recognition. The reason is that classification methods reduce the size of the search space to the fingerprints of the same category before matching. First, we suggest a method to extract region of interest (ROI) which have real information about fingerprint from the image. And then we propose a feature extraction method which combines gray level co-occurrence matrix (GLCM) and wavelet features. Finally, we compare the performance of our proposed method with the existing method which use only GLCM as the feature of fingerprint by using the multi-layer perceptron and support vector machine.

Validation of DEM Derived from ERS Tandem Images Using GPS Techniques

  • Lee, In-Su;Chang, Hsing-Chung;Ge, Linlin
    • Journal of Korean Society for Geospatial Information Science
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    • v.13 no.1 s.31
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    • pp.63-69
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    • 2005
  • Interferometric Synthetic Aperture Radar(InSAR) is a rapidly evolving technique. Spectacular results obtained in various fields such as the monitoring of earthquakes, volcanoes, land subsidence and glacier dynamics, as well as in the construction of Digital Elevation Models(DEMs) of the Earth's surface and the classification of different land types have demonstrated its strength. As InSAR is a remote sensing technique, it has various sources of errors due to the satellite positions and attitude, atmosphere, and others. Therefore, it is important to validate its accuracy, especially for the DEM derived from Satellite SAR images. In this study, Real Time Kinematic(RTK) GPS and Kinematic GPS positioning were chosen as tools for the validation of InSAR derived DEM. The results showed that Kinematic GPS positioning had greater coverage of test area in terms of the number of measurements than RTK GPS. But tracking the satellites near and/or under trees md transmitting data between reference and rover receivers are still pending tasks in GPS techniques.

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Robot Locomotion via RLS-based Actor-Critic Learning (RLS 기반 Actor-Critic 학습을 이용한 로봇이동)

  • Kim, Jong-Ho;Kang, Dae-Sung;Park, Joo-Young
    • Journal of the Korean Institute of Intelligent Systems
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    • v.15 no.7
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    • pp.893-898
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    • 2005
  • Due to the merits that only a small amount of computation is needed for solutions and stochastic policies can be handled explicitly, the actor-critic algorithm, which is a class of reinforcement learning methods, has recently attracted a lot of interests in the area of artificial intelligence. The actor-critic network composes of tile actor network for selecting control inputs and the critic network for estimating value functions, and in its training stage, the actor and critic networks take the strategy, of changing their parameters adaptively in order to select excellent control inputs and yield accurate approximation for value functions as fast as possible. In this paper, we consider a new actor-critic algorithm employing an RLS(Recursive Least Square) method for critic learning, and policy gradients for actor learning. The applicability of the considered algorithm is illustrated with experiments on the two linked robot arm.

Origin of Banded $B_t$ Horizons in Sandy Deposits ($B_t$ Band의 형성 과정)

  • 오경섭
    • The Korean Journal of Quaternary Research
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    • v.3 no.1
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    • pp.35-45
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    • 1989
  • In Korean peninsula as well as in Western European Countries, we can find, reddish bands in sandy deposits of various origin. These bands (called "$B_t$ Band"), composed of fine material, are regularly intervalled and parallel to topography. This study is tring to elucidate their origin and associated milieux, with a group of methods and techniques (field survey, micromorphological analysis, granulometry, X-ray diffractometry of clay minerals...). $B_t$ Bands are not sedimentological origin. They were formed by superposition of two type accumulations in the sandy profile, triggered by different mechanisms: 1) accumulation in banded form, concerning silty heterometric material and micas, oweing to cryophoretic forces operating in course of deep freezing of sandy deposits: 2) illuviation of ferrugineous clays in the precedants bands, migrated in chelate state by soil water. The first processes are associated with very cold and humid climate in which freeze soil more than 3m in depth. The second, cold and humid climate in which podzolizattion is generalized. In case of South Korea and Western Europe, these two types of climates are not present circumstance, but Recent Quaternary (probably since the Wurm).the Wurm).

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Reconsideration on the Importation Pathway of Ancient Korean Rice(Oryzar sativar L.) (고대 한반도에서 재배된 벼의 전래 경로에 대한 고찰)

  • Park, Tae-Shik
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.54 no.1
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    • pp.119-123
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    • 2009
  • Importation pathway of rice cultivar into Korea was re-established with considering ancient geo-ecological characteristics of the Sororibyeo excavated from Cheongwon. It is assumed that Sororibyeo settled down in Korea by the importation pathway along the southern seashore of China through old downstream of Geumgang by a southern Korean human race when China and Korea were not yet separated each other by the Yellow Sea. This importation pathway was designated as "Old Geumgang-Sorori Rice Road", in this study. It is further inferred that Korean Peninsula was geographically isolated by ocean after the Ice Age. In consequence, Gawajibyeo, an ancient rice with little genetic variation, was evolved from Sororibyeo, which is estimated to evolve into rice cultivar in Korean Peninsula.

Multiple SVM Classifier for Pattern Classification in Data Mining (데이터 마이닝에서 패턴 분류를 위한 다중 SVM 분류기)

  • Kim Man-Sun;Lee Sang-Yong
    • Journal of the Korean Institute of Intelligent Systems
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    • v.15 no.3
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    • pp.289-293
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    • 2005
  • Pattern classification extracts various types of pattern information expressing objects in the real world and decides their class. The top priority of pattern classification technologies is to improve the performance of classification and, for this, many researches have tried various approaches for the last 40 years. Classification methods used in pattern classification include base classifier based on the probabilistic inference of patterns, decision tree, method based on distance function, neural network and clustering but they are not efficient in analyzing a large amount of multi-dimensional data. Thus, there are active researches on multiple classifier systems, which improve the performance of classification by combining problems using a number of mutually compensatory classifiers. The present study identifies problems in previous researches on multiple SVM classifiers, and proposes BORSE, a model that, based on 1:M policy in order to expand SVM to a multiple class classifier, regards each SVM output as a signal with non-linear pattern, trains the neural network for the pattern and combine the final results of classification performance.

A Study on the Cultivation of Enteromorpha prolifera(Muller) J.Agardh, Chlorophyta in Korea (녹조식물 가시파래, Enteromorpha prolifera의 양식연구)

  • 윤장택;조용철;공용근
    • Journal of Aquaculture
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    • v.16 no.1
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    • pp.44-50
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    • 2003
  • This study aimed to develop the methods of growing Enteromorpha prolifera natural seedlings in its natural habitat and artificial indoor seedlings by inducing spore release. Likewise, the study examined the possibility of mass production by developing cultivation techniques with cultivating examination. The natural seedling of E.prolifera thrived in a sea area composed of sand and mud, which Is its natural habitat. Growing of this alga on the seedling frame 20 cm high from the bottom at the intertidal zone in summer and 40 cm high in fall was found to be very effective. However, enabling the best attachment rate for artificial indoor seedling requires inducing spore release after drying the mature thalli in a dark place fur about 12∼24 hours and setting seedling nets in a dark water tank (spore solution) for 24 hours. Breeding E.prolifera in a pole-system farm is best done in shallow sea areas with mud or mud and sand geological feature. However, floating-system lam is better for deep-sea areas with fast current. Ideal farming places are sea areas with plenty of nutritional salt and safe places that protect the lam facilities against billows. Furthermore, an exposure method on seawater surface to produce larger output should be used.