• Journal of the Society of Naval Architects of Korea
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• v.38 no.4
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• pp.23-29
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• 2001

An Obstacle Avoidance System(OAS) of Underwater Vehicle(UV) in diving and steering plane is investigated. The concept of Imaginary Reference Line(IRL), which acts as the seabed in the diving plane, is introduced to apply the diving plane avoidance algorithm to the steering plane algorithm. Furthermore, the distance to the obstacle and the slope information of the obstacle are used for more efficient and safer avoidance. As for the control algorithm, the sliding mode controller is adopted to consider the nonlinearity of the equations of motion and to get the robustness of the designed system. To verify the obstacle avoidance ability of the designed system, numerical simulations are carried out on the cases of some presumed three-dimensional obstacles. The effects of the sonar and the clearance factor used in avoidance algorithm are also investigated. Through these, it is found that the designed avoidance system can successfully cope with various obstacles and the detection range of sonar is proven to bea significant parameter to the performance of the avoidance.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1045-1049
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• 2005

In this paper, the dynamic crawling of a five-bar planar mechanism is investigated. One complete cycle of the crawling selected in this study consists of four different steps, i) sliding at one contact point between the mechanism and the ground, ii) changing its configuration without sliding at two contact points, iii) sliding at the other contact point, and iv) again changing its configuration without sliding at two contact points. In this type of crawling, the crawling mechanism maintains the shape of the parallel structure throughout a complete crawling cycle. The modeling algorithm for serial manipulators proposed by M. Thomas and et al.[1] is employed by introducing imaginary joints and links which represent the contact interfaces between the one end of the mechanism and the ground, while the other end of the mechanism is regarded as an end-effector of the imaginary serial manipulator which treats the reaction force and torque at the contact point as external forces. Then, a complete cycle of dynamic crawling of the mechanism is investigated through various computer simulations. The simulation result show that the stable crawling characteristics of the mechanism could be secured when the proper configurations depending on specified frictional constraints are met.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.12 no.5
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• pp.107-114
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• 2012

In this paper, the concerned existing blind equalizer convergence rate and residual inter-symbol interference using constellation reduced and cost function by separation the real part and an imaginary part, the dual structure CR-CMA(constellation Reduction CMA). The CMA methed compensates amplitude but does no compensate phase, On the other hand, The CMA method compensates both the amplitude and the phase but it has the convergence rate problem, and the MCMA method is a way to solve the phase problem of CMA method compensates both the amplitude and the phase after respectively calculating the real part and imaginary part components. Proposal a new method that the dual structure of CR-CMA, the cost function and error function and respectively calculating the real part and imaginary part components can advantages by improving the CMA and the MCMA algorithms so that the amplitude and phase retrieval and constellation reduce the residual ISI and faster convergence rate and performance is good SER (Symbol Error Ratio) was confirmed by computer simulations.

• Journal of Korea Multimedia Society
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• v.20 no.2
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• pp.225-233
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• 2017

Line-laser beams are used for accurate measurement of 3D shape, which is robust to external illumination. For depth measurement, we project a line-laser beam across an object from the face and take an image of the beam on the object surface using a CCD camera at some angle with respect to the face. For shape measurement, we project parallel line-laser beams with narrow line to line distance. When a layer of thin materials attached to a cylinder is long narrow along its circumference, we can measure the shape of the layer with a small number of parallel line beams if we project line beams along the circumference of the cylinder. Measurement of the depth of the attached materials on a line-laser beam is based on the number of pixels between an imaginary line along the imaginary cylinder without the attached materials and the beam line along the materials attached to the cylinder. For this we need to localize the imaginary line in the captured image. In this paper, we model the shape of the line as an ellipse and localize the line with least square estimate. The proposed method results in smaller error (maximum 0.24mm) than a popular 3D depth camera (maximum 1mm).

• The Transactions of the Korean Institute of Power Electronics
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• v.8 no.6
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• pp.576-584
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• 2003

This paper presents a new control method of single-phase active power filter(APF) for the compensation of harmonic current components in nonlinear loads. Constructing a imaginary second-phase giving time delay to load currents, making single-phase system into the system that has two phases, complex calculation is possible. In the previous method, it made a imaginary-phase lagged to the load current T/4(here T is the fundamental cycle), but in proposed method, the new signal, which has the delayed phase through the filter, using the phase-delay property of low-pass filter, was used to the second phase. Instantaneous calculation of harmonic current is possible, because two phase have different phase. In this paper, it was done with instantaneous calculation using the rotating reference frames(RRF) that synchronizes with source-frequency, a reference of compensation currents, not applying to instantaneous reactive power theory which uses the existed fixed reference frames. The simulation and experiment about R-L loads using the current source were carried out, and the effect of the proposed method was preyed through the result of this experiment.

• The Journal of the Society of Korean Medicine Diagnostics
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• v.13 no.1
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• pp.1-9
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• 2009

Objectives : If patients notice a symptom indicating inveterate dyspepsia but they don't have any problem around gastroscope, they get diagnosed as a functional dyspepsia or an imaginary stomach disease, but to overcome the limitations of these diagnoses, we are analyzing them for the common feature and are looking for a new diagnostics for them. Methods : Based on our survey with 122 patients with inveterate dyspepsia, we analyzed the period of onset, eating habits, the main symptoms, and observations on the gastroscope. We also analyzed the function of the stomach and intestines by EAV examinations, and the outer walls of the stomach and intestines by subdividing the level of coagulation into six with abdominal palpation. Results : We figured out that people who appeals about inveterate dyspepsia have had long period of onset, and that they had bad eating habits, shoulder stiffness, neck stiffness, headache, dizziness, etc. These are all the similar symptoms beside dyspepsia, which indicates that it is a syndrome. From about 70%, they didn't had particular problem in gastroscope, and as to be seen from the result of EAV examination, their stomachs and intestines had become functionless. Also, we were able to feel a stiffened tissue through abdominal palpation. Conclusion : Through this investigation, we found out that what the gastroscope can not find so that gets diagnosed as a functional dyspepsia or an imaginary stomach disease can be diagnosed as a syndrome called damjeok by overcoming the limitation utilizing the survey, EAV examinations, and abdominal palpation. We can find a mighty significance from the fact that it can be diagnosed as a syndrome.

• The Research Journal of the Costume Culture
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• v.25 no.2
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• pp.130-144
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• 2017

The purpose of this study is to apply iconology to discover the symbolic system of imaginary animals focused on four representative auspicious animals in Korean folk paintings. Study methods included literature review of folk paintings, iconological analytics books, and articles. A total of 16 folk paintings of four auspicious animals in the Joseon Dynasty were analyzed using Panofsky's iconology. The four auspicious animals were Yong(dragon), Bonghwang(the eastern version of the phoenix), Shingoo (divine turtle), and Kirin(one-horned combination of a dragon and horse). According to iconological analysis, Yong is a typical symbol of royal authority, a deity of water as an object of respect with a remarkable talent of transformation, and in iconographical interpretation, represents reverence for transcendent power. Bonhwang is the symbol of a king, sun worship, the emblem of nobility and integrity, and in iconographical interpretation, the psychic bing in the sky. Shingoo is fortune prophecy, longevity and immortality, an envoy of deity, and according to iconographical interpretation, the organic view of the world. Kirin is a divine benign creature, a symbol of talent and honor, mediator between sky and earth, and in iconographical interpretation, an expression of Confucian ideology. This study produced three results. First, the four auspicious animals projected the human hope to overcome human limitations through divine creatures with mythical abilities. Second, they reflected everyday common hopes and values of pursuing fortunes and happiness. Third, the four auspicious animals' iconology was not independent of each other; it seemed to be common to and combined with each other.

• Korean Institute of Interior Design Journal
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• v.17 no.6
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• pp.11-20
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• 2008

The purpose of this study is to find out the theoretical background of spatial fantage effects in Piranesi etching "Le Carceri" called 'Architectural Capriccio'. In a life time Piranesi created a prodigious oeuvre of dramatic and fantastic images about magnificent buildings and mysterious ruins and prison. The increasing "tourism" after the middle of the 18th century contributed a lot to Piranesi's success. He was famous for his poetic views of Rome and also his fantastic imaginary interiors. The terms "Capriccio" and "Veduta" are strongly connected with Piranesi's work. The term Veduta describes a form of landscape depiction in print with close to reality imitation of the scenery, whereas the "Capriccio" contains the elements of invention in artificial architectural landscape. Trained in Venice as an engineer and architect, his studies had included perspective and stage design. These skills, allied to his deep knowledge of archaeology, provided the substance for his Veduta, etchings of ancient Rome. But his most remarkable etchings are those of imaginary interiors, the Carceri d'Invenzione(Imaginary Prisons), a series of capric plates issued in 1750. It appears to Piranesi etching 'Le Carceri' that 18th century experimental scenography's effect very strongly. Also, it can understand about "Scena per Angolo" which was revealed by Ferdinando Galli Bibiena that Piranesi spatial view and viewpoint deconstruction operate motive and cause. Piranesi's spatial fortification was influence by Filippo Juvarra's spatial concept. As a result of this research will be foundation of understanding deeply that Piranesi etching has been affect to present architecture and art.

• Cross-Cultural Studies
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• v.49
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• pp.33-58
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• 2017

As a living space, house constitutes a good part of inhabitants' life, making the rhythm of life. This rhythm tends to be reflected into the house, establishing a sort of intercommunications between the house and its inhabitants. Becoming a living element, the house can endow the writer with literary resources. It is interrelated with its inhabitants. Thus, Duras' work preserves many invisible and fusional traces of links between her characters and the house. With her writing, the house displays important traces of life, with which a body of meaning is to be formed. It implies habits, imprints, links, and so on. Here, its projection into the imaginary also takes place for our writer. With this perspective in view, Duras is supposed to objectify her characters as physical and imaginary bodies. This introduces the passage from the real to the imaginary and vice versa. Unknown stories hidden behind the living places can come to manifest themselves through her writing.

• Journal of the Korean Institute of Intelligent Systems
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• v.18 no.5
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• pp.605-610
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• 2008

There are many methods for Human-Computer Interface. Recently, many researchers are studying about Brain-Signal this is because not only the disabled can use a computer by their thought without their limbs but also it is convenient to general people. But, studies about it are early stages. This paper proposes an EEG signals measurement and analysis methods for Brain-Computer Interface. Our purpose of this research is recognition of subject's intention when they imagine moving their arms. EEG signals are recorded during imaginary movement of subject's arms at electrode positions Fp1, Fp2, C3, C4. We made an analysis ERS(Event-Related Synchronization) and ERD(Event-Related Desynchronization) which are detected when people move their limbs in the ${\mu}$ waves and ${\beta}$ waves. Results of this research showed that ${\mu}$ waves are decreased and ${\beta}$ waves are increased at left brain during the imaginary movement of right hand. In contrast, ${\mu}$ waves are decreased and ${\beta}$ waves are increased at right brain during the imaginary movement of left hand.