• Title/Summary/Keyword: Unknown control direction

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The Hidden Object Searching Method for Distributed Autonomous Robotic Systems

  • Yoon, Han-Ul;Lee, Dong-Hoon;Sim, Kwee-Bo
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.1044-1047
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    • 2005
  • In this paper, we present the strategy of object search for distributed autonomous robotic systems (DARS). The DARS are the systems that consist of multiple autonomous robotic agents to whom required functions are distributed. For instance, the agents should recognize their surrounding at where they are located and generate some rules to act upon by themselves. In this paper, we introduce the strategy for multiple DARS robots to search a hidden object at the unknown area. First, we present an area-based action making process to determine the direction change of the robots during their maneuvers. Second, we also present Q learning adaptation to enhance the area-based action making process. Third, we introduce the coordinate system to represent a robot's current location. In the end of this paper, we show experimental results using hexagon-based Q learning to find the hidden object.

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An Adaptive Input Data Space Parting Solution to the Synthesis of N euro- Fuzzy Models

  • Nguyen, Sy Dzung;Ngo, Kieu Nhi
    • International Journal of Control, Automation, and Systems
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    • v.6 no.6
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    • pp.928-938
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    • 2008
  • This study presents an approach for approximation an unknown function from a numerical data set based on the synthesis of a neuro-fuzzy model. An adaptive input data space parting method, which is used for building hyperbox-shaped clusters in the input data space, is proposed. Each data cluster is implemented here as a fuzzy set using a membership function MF with a hyperbox core that is constructed from a min vertex and a max vertex. The focus of interest in proposed approach is to increase degree of fit between characteristics of the given numerical data set and the established fuzzy sets used to approximate it. A new cutting procedure, named NCP, is proposed. The NCP is an adaptive cutting procedure using a pure function $\Psi$ and a penalty function $\tau$ for direction the input data space parting process. New algorithms named CSHL, HLM1 and HLM2 are presented. The first new algorithm, CSHL, built based on the cutting procedure NCP, is used to create hyperbox-shaped data clusters. The second and the third algorithm are used to establish adaptive neuro- fuzzy inference systems. A series of numerical experiments are performed to assess the efficiency of the proposed approach.

Obstacle Avoidance Method for Multi-Agent Robots Using IR Sensor and Image Information (IR 센서와 영상정보를 이용한 다 개체 로봇의 장애물 회피 방법)

  • Jeon, Byung-Seung;Lee, Do-Young;Choi, In-Hwan;Mo, Young-Hak;Park, Jung-Min;Lim, Myo-Taeg
    • Journal of Institute of Control, Robotics and Systems
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    • v.18 no.12
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    • pp.1122-1131
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    • 2012
  • This paper presents obstacle avoidance method for scout robot or industrial robot in unknown environment by using IR sensor and vision system. In the proposed method, robots share the information where the obstacles are located in real-time, thus the robots can choose the best path for obstacle avoidance. Using IR sensor and vision system, multiple robots efficiently evade the obstacles by the proposed cooperation method. No landmark is used at wall or floor in experiment environment. The obstacles don't have specific color or shape. To get the information of the obstacle, vision system extracts the obstacle coordinate by using an image labeling method. The information obtained by IR sensor is about the obstacle range and the locomotion direction to decide the optimal path for avoiding obstacle. The experiment was conducted in $7m{\times}7m$ indoor environment with two-wheeled mobile robots. It is shown that multiple robots efficiently move along the optimal path in cooperation with each other in the space where obstacles are located.

The Quantitative Analysis of SB Latex Contents in Coating Color and Coating Layer of Coated Paper Using FT/Raman Spectroscopy (FT/RAman을 이용한 도공액과 도공지의 도공층 내의 SB Latex 정량분석)

  • 이복진;정순기;윤동호;마금자
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.31 no.4
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    • pp.16-22
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    • 1999
  • The quantitative analysis of SB latex contents in coating color and coated paper was investigated with FT/Raman spectroscopy. From the measured FT/IR and FT/Ramon spectra, the peaks of coating color were compared with those of each compoents . Calibration curves were obtained by the area of latex peaks and PLS method of QuantIR program. The relation of predicted values in PLS method and actual values in coating mixtures and coating layer was examined. The components of coating layer in coated paper were investigated by EDS , X-mapping and SEM, The contents of latex in z-direction were calculated in the coating layer of unknown coated paper. The latex concentration measurements of Top layer and Pre layer in double coated paper show that each layer has different value. In single coated paper, it is clear that the latex concentration is highest at the surface and decreases with an increase of depth. From those results it is indicated that the latex migrates to the coated surface. The result of this study may be applied to the binder migration study and the quality control in paper mill.

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Precision indices of neural networks for medicines: structure-activity correlation relationships

  • Zhu, Hanxi;Aoyama, Tomoo;Yoshihara, Ikuo;Lee, Seung-Woo;Kim, Wook-Hyun
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.481-481
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    • 2000
  • We investigated the structure-activity relationships on use of multi-layer neural networks. The relationships are techniques required in developments of medicines. Since many kinds of observations might be adopted on the techniques, we discussed some points between the observations and the properties of multi-layer neural networks. In the structure-activity relationships, an important property is not that standard deviations are nearly equal to zero for observed physiological activity, but prediction ability for unknown medicines. Since we adopted non-linear approximation, the function to represent the activity can be defined by observations; therefore, we believe that the standard deviations have not significance. The function was examined by "leave-one-out" method, which was originally introduced for the multi-regression analysis. In the linear approximation, the examination is significance, however, we believe that the method is inappropriate in case of nonlinear fitting as neural networks; therefore, we derived a new index fer the relationships from the differential of information propagation in the neural network. By using the index, we discussed physiological activity of an anti-cancer medicine, Mitomycine derivatives. The neuro-computing suggests that there is no direction to extend the anti-cancer activity of Mitomycine, which is close to the trend of anticancer developing.

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Simultaneous Adjustment of the Korea Precise Primary Geodetic Network by Development Method (우리 나라 정밀측지망(精密測地網)의 동시조정(同時調整))

  • Choi, Jae Hwa;Choi, Yun Soo
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.13 no.1
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    • pp.151-159
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    • 1993
  • In conjunction with a vertical network. horizontal geodetic control points provide the basic framework for topographic mapping and legal survey. The design of such networks as well as the technical means for obtaining their coordinates have been changed in time, and therefore Korea National Geographic Institute has planned and observed the precise geodetic network since 1975. The aim of this study is to investigate the systematic distortions of the precise geodetic network in Korea implementing by the simultaneous adjustment. The results show that there are large discrepancies between adjusted and public coordinates in Chun-nam and Kyung-buk areas. The coordinate discrepancies are mainly due to the non-rigorous adjustment method and the disregard of the orientation unknown of the first direction for some blocks.

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Morphology, Phylogeny and Ecology of Hyphomycetes Hyperparasitic to Rusts

  • Park, Mi-Jeong;Park, Jong-Han;Hong, Seung-Beom;Shin, Hyeon-Dong
    • 한국균학회소식:학술대회논문집
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    • 2015.05a
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    • pp.55-55
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    • 2015
  • Rust is one of the most destructive diseases on economically important plants such as agricultural and horticultural crops, as well as forest trees [1]. Chemical treatment is the most effective means to control rust, but use of the chemical fungicides involves inevitable risks to human health and environment [2]. Unfortunately, biocontrol is currently impracticable for rust disease management [3]. It is necessary to exploit biocontrol agents to help prevent rust diseases. As a fundamental research for future development of biocontrol agents for rusts, biodiversity of hyperparasites occurring on rust fungi was investigated. During 2006-2010, 197 fungal isolates of the rust hyperparasites were collected and isolated from various combinations of mycohosts and plant hosts in many regions of Korea. Based on morphological and molecular data, they were identified as 8 genera and 12 species. Besides, phylogenetic relationships between the hyperparasites and related taxa were inferred. A total of 114 isolates of Pseudovirgaria were obtained from rust pustules of Phragmidium spp. and Pucciniastrum agrimoniae infecting rosaceous plants. Phylogenetic analysis using multigene sequences revealed a high level of genetic variability among many isolates of Pseudovirgaria and close correlation between the isolates and mycohosts. Only two species of Pseudovirgaria, P. hyperparasitica and P. grisea are often difficult to distinguish by their morphological similarity, but on the molecular basis they were clearly differentiated from each other. There had been no previous record of P. grisea outside Europe, but the present study has proved its presence in Korea. Among six distinct groups (five of P. hyperparasitica and one of P. grisea) within the Pseudovirgaria isolates, each lineage of P. hyperparasitica was closely associated with specific mycohosts and thus might have cospeciated with their mycohosts, which probably led to coevolution. Although P. grisea possesses a host preference for Phragmidium species occurring on Rubus, it was not specific for a mycohost. P. grisea seems to evolve in the direction of having a broad mycohost range. Seventeen isolates of Verticillium-like fungi were isolated from rust sori. Based on morphological data and DNA sequence analysis, the isolates were identified as three Lecanicillium species, viz. L. attenuatum, Lecanicillium sp. 1, Lecanicillium sp. 2, and V. epiphytum. The unidenified two species of Lecanicillium appear to be previously unknown taxa. Sixty-six isolates of miscellaneous hyphomycetes belonging to 6 species of 5 genera were obtained from pustules of rust fungi. On the basis of morphological and molecular analyses, the miscellaneous hyphomycetes growing on rusts were identified as Acrodontium crateriforme, Cladophialophora pucciniophila, Cladosporium cladosporioides, Phacellium vossianum, Ramularia coleosporii, and R. uredinicola.

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The Changes of Mortality Differentials by Socioeconomic Determinats(1970~86) : Based on Death Registration Data (사회$\cdot$경제적 요인별 차별 사망력의 변화: 1970 ~ 1986)

  • 윤덕중;김태헌
    • Korea journal of population studies
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    • v.12 no.2
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    • pp.1-21
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    • 1989
  • For the analysis of mortality differentials by socioeconomic factors based on death registration data, we have considered four variables : place of residence, educational attainment, marital status and occupation. The age range adopted were 5 to 64 years of age for place of residence, and 25 to 64 years of age for the other factors. The mortality differentials by socioeconomic variables were clear and in the expected direction: mortality levels among urban residents, better educated groups, and non- agricultural workers were lower than among the other sub- groups. The average mortality level in rural areas is much higher than in urban areas : the rural mortality levels were at least double the urban levels at ages below 40 years, but became smaller after age 40, and no clear differentials by urban I rural residence increased until 1974~76 for the both sexes, but since the then differentials have declined slowley for both sexes. This changing pattern of mortality differentials by place of residence can be explained by historical socioeconomic development : the development generally started in urban areas, and rural areas followed : in the course of socioeconomic development the differences between the death rates in the two areas became smaller and finally the mortality levels in the two areas became nearly the same, as is found in the developed countries nowadays. The inverse relationships between mortality and educational level became stronger between the periods 1970~72 and 1984~86, but showed the same atterns of mortality differentials in both period : larger differences among the younger age groups, and for males, than among the older age groups, and for females. The increasing mortality differentials in the fourteen-year period between 1970~72 and 1984~86 were caused by inadequate living standards of the non- educated, whose proportion in the total population, however, dropped sharply during that period. Also, the much lower proportions of low - educated groups or of persons with no formal education among males than females helped to establish the clearly pronounced differentials. The mortality differentials by marital status in Korea showed the usual pattern : the mortality rates of the married in each age and sex group were clearly lower than those of others during the fourteen-year period between 1970~72 and 1984~86. In Korean society which remotes universal marriage, the never married recorded especially high death rates, presumably mainly because of ill - health, but also possibly because of the stigma attached to celibacy. However, the mortality differentials by marital status changed with the changes in the proportionate distribution by marital status during the period : the differences between the death rates of the married and never married groups became smaller, the proportion of the never married group increased : in contrast, the differences between mortalities of the married and widowed / divorced / separated groups widened, with the decrease in the proportion of the later group ; this tendency was perticularly marked for females. Occupational groups also showed clear mortality differences : among four occupational groups mortality of males was highest among agricultural workers and lowest among 'professional, admi-nistrative and clerical workers, However, when the death rates were standardized by educational level, the death rates by occupation in age group 45~64 years were nearly the same (excet for the mixed group consisting of unemployed, students, military servicemen and unknown). Therefore, the clear mortality dfferentials by occupation in Korea resulted mainly from the differences in educational level between different occupation groups. Since socioeconomic characteristics are related to each other, the net effect of each variable was examined. Each of the three variables - ducational level, marital status and urban / rural residence affected significantly Korean adult mortality when the effects of the other variables were controlled. Among the three variables educational level was the most important factor for the determination of the adult mortality level. When male's occupation was added to the above three variables, the effects of occupation on adult mortality were notably smaller after control for the effects of the other three variables while the net effects of these three variables were nearly the same irrespectively whether occupation was included or not. Thus, the differences in educational level (mainly), place of residence and marital status bring out the clear differences in observed mortality levels by occupation.

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The Origin and Formation of Korean Public Art Theories in the 1980s (1980년대 민중미술론의 기원과 형성)

  • Choi, Youl
    • The Journal of Art Theory & Practice
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    • no.7
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    • pp.37-64
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    • 2009
  • The theories of Korean Public Art originated by the artists who were against dictatorship and they associated with democratic politicians. They criticized the Fine art that were supported by the dictatorship and gave their efforts for restoration of 'resistance paintings(against dictatorship)', 'proletarian painting', 'realism painting'. In addition, they participated new social ideology(democracy) movement and demonstrated for their rights in arts. These became the main kernel the public art theory was initiated. The public artists splitted into several different parts and participated in the democratic social movement as well as the art movement for freedom. They opened various art exhibitions within different genre, diverse space for various art section such as an exhibition hall, a factories, a university, or a congregation square. Furthermore, the public art theorists published their divergent views through newspaper/broadcasting or unauthorized printed materials. Most of the public artist and the theorists kept their relationship strongly until 1985, the time when 'National Arts Association' started. In 1983 and 1984, they were clearly separated into two parts; artists(move only in art museums) and activists(move in public spaces like school, convention square etc). Their ideological separation also took out national problems. The division; professional artists and armatures, became the social issue as a social stratification matter. And in creating method, there are also other conflicts; critical realism, and public realism as well as western painting and traditional one. These kinds of separation and conflicts made different Public artists associations, under divergent names; 'Reality and Speak'(R&S), 'KwangJu Art Association', 'Durung', 'Dang(Land)', and 'Local Youth Students Association'. In addition, their ideology and pursuit toward art movements were very difference. However, the differences and conflicts weakened When the oppression of democratic education from new dictatorship(Pres. Jun, Doo Hwan) came out. In August. 1985 the government opened to the public so called, 'The draft of School stabilization law'(Hankwon Anjung Bup) to control the teachers' rights and that initiated bigger street demonstration and conflicts between police and educators. In November.1985, assembly meeting of National Arts Association in democracy opened as 'ONE' combined organization. In this presentation, I'd like to summarize the stream of art movement until 1984, and clarify the main art theories that lead the Public Art Movements in 1980s. The main theories in 1980s are crucial because they become the origin of public art theories. This presentation started with O,youn's "Hyunsil Dong In the first declaration" and explained the absent of practice in 1970s. In addition, Won, Dong Suk 's theory was mentioned as all over struggles in theories before 1980s. GA and R&S 's founding declarations in 1970s were the start of public art theorists' activities and this article reported the activities after the declarations. First, realism base on the consciousness of reality. Second, practice art democratization based on the ideology. Third, the subject of public art movement based on understanding people's social stratification structure. Fourth, the matters of national forms and creative ways in arts based on showing reality. Fifth, the strong points in arts that the practitioners accepted. About the public art theories around 1984, I discussed the dividing point of public art theories that were shown in 'generation theory', 'organization theory', and 'popularization theory' by the practitioners. The public realism theory that subjects the contradiction of reality and point out the limits of critical realism not only showing the new creative ways but also giving the feeling of solidarity to the public art activist groups. After that, public art movements expressed 'Dismentlement of Capitalism' and 'Public revolution'. In addition, the direction of public art movements were established strongly. There were various opinions and views during the start and formation of the public art theories. The foundation of theorists activities derived from the practitioners who had the concept based on stratification and nationalism. The strong trend of group division spreaded out by practitioners who opened art work together in factories, universities, squares and rural areas. Now many lively active practitioners are gone to the other field not related with arts, and others join into professional art field not public art one with unknown reason. The theorists have the same situation with the practitioners. It means to me that theory always have to be based on the practice.

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