• Journal of the Institute of Electronics Engineers of Korea CI
• /
• v.47 no.4
• /
• pp.102-108
• /
• 2010

The photovoltaic system changes solar energy into DC by solar cell and this DC is inverted into AC which is used in general houses by inverter. Recently, the use of power of the photovoltaic system is increased. Therefore, the study of 3 phase solar system to transmit large power is very important. This paper proposes a method that finds simply faults and diagnoses the switch open faults of 3-phase pulse width modulation (PWM) inverter of grid-connected photovoltaic system. The proposed method in $\alpha\beta$ plane uses the patterns of trajectory image as the characteristic parameters and differenciates a normal state and open states of switches. Then, the result is made into tree. The tree is composed of 21 fault patterns and the parameters to classify faults are a shape, a trajectory area, a distributed angle, and a typical vector angle. The result shows that the proposed method diagnosed fault diagnoses, classified correctly them, and made a pattern tree by fault patterns.

• Journal of the Korean Society of Costume
• /
• v.53 no.7
• /
• pp.57-68
• /
• 2003

The purpose of this study is to develop a creative perspective technique in fashion illustration through analyzing perspective in visual art experienced a great variety. This study was analyzed by examining the general theories based on the discovery of perspective and investigating the modern perspective in fashion illustration related to the method of spatial expression in visual art. A complex perspective of existing perspective gives the effect of reapperance of actual space and three-dimentional form in a plane. Because of being used as not only one perspective technique but also some perspectives technique, its expression can be more realistic. An amplified perspective gives the effect of visual illusion just like being suck in space inside and come out from screen outside by distorting the human body. A confused perspective of space gives the visual illusional effect of collapsing actual space and misunderstanding three-dimensional form by distorting the form of the space and changing the nature as an object of fashion. A reiterated or duplicated perspective gives effect of interpreting invisible space as imaginary space by overlapping and eliminating the object of fashion. An irrational perspective of spatial illusion gives the effect of disorganization experienced thinking by strange shapes and new recognition of irrational space by extraordinary visual connection. It has a tendency to surrealism. In conclusion, the modern perspective in fashion illustration has made the best use of not only new perspective since 1980, but general perspective before 1980. By the modern perspective expression. the viewer has made a chance to experience imaginary spaces indirectly, and the author has been able to express emotions by his or her new attempt in the screen.

• Journal of the Korean Society for Precision Engineering
• /
• v.17 no.7
• /
• pp.113-123
• /
• 2000

In the navigation for a mobile robot, the collision avoidance with unexpected obstacles is essential for the safe navigation and it is independent of the technique used to control the mobile robot. This paper presents a new collision avoidance algorithm using neural network for the safe navigation of the autonomous mobile robot equipped with CAN and ultrasonic sensors. A tracked wheeled mobile robot has a stability and an efficiency to move on a rough ground. And its mechanism is simple. However it has difficulties to recognize its surroundings. Because the shape of the tracked wheeled mobile robot is a square type, sensor modules are generally located on the each plane surface of 4 sides only. In this paper, the algorithm using neural network is proposed in order to avoid unexpected obstacles. The important character of the proposed algorithm is to be able to detect the distance and the angle of inclination of obstacles. Only using datum of the distance and the angle, informations about the location and shape of obstacles are obtained, and then the driving direction is changed. Consequently, this algorithm is capable of real time processing and available for a mobile robot which has few sensor modules or the limited sensing range such as a tracked wheeled mobile robot. Effectiveness of the proposed algorithm is illustrated through a computer simulation and an experiment using a real robot.

• Journal of Korean society of Dental Hygiene
• /
• v.10 no.5
• /
• pp.807-817
• /
• 2010

Objectives : The purpose of this study was to analyzes the job implementation of dental hygienist at dental hospital(university), dental clinic and general hospital in the city of Gwangju. Methods : The subjects in this study were dental hygienists who worked at dental hospital(university), dental clinic and general hospital in the city of Gwangju. A survey was conducted by post from June 10 to August 10. Out of the collected data, 204 answer sheets were analyzed. Results : 1. 'Medical & Dental history taking', 'Extra & Intra oral examination' and 'Dental hygiene care plane' in dental clinic were significantly higher than dental hospital(university) and general hospital(p<0.001). 'Remove of extrinsic stain' and 'Treatment of hypersensitivity tooth' in dental clinic and general hospital were significantly higher than dental hospital(university)(p<0.001). 'Preventive dental caries treatment' and 'Diet control' were shown the low frequency of job implementation. 2. Almost task elements of dental assistance duty shown that dental hygienists under the 24 years old were significantly higher dental hygienists over the 30 years old(p<0.05) and dental clinic and general hospital were significantly higher than dental hospital(university)(p<0.05) in frequency of job implementation. 3. 'Dental staff supervision', 'Patient management' and 'Dental chart arrangement' shown that dental hygienists over the 30 years old were significantly higher than dental hygienists under the 24 years old in frequency of job implementation(p<0.05). 'Infection control' of dental hygienists over 30 years old was significantly lower than dental hygienists under the 24 years old(p<0.001). Conclusions : The results of this study indicate that a scope of dental hygienists' job need to extend also in order to accomplish a job efficiently, is suggested that the effort is necessary to improve a quality of dental hygienist and to change of recognition of the dentist about dental hygienists' job.

• International Journal of Fuzzy Logic and Intelligent Systems
• /
• v.5 no.3
• /
• pp.230-245
• /
• 2005

In this paper, we develop a gesture-based input device equipped with accelerometers and gyroscopes. The sensors measure the inertial measurements, i.e., accelerations and angular velocities produced by the movement of the system when a user is inputting gestures on a plane surface or in a 3D space. The gyroscope measurements are integrated to give orientation of the device and consequently used to compensate the accelerations. The compensated accelerations are doubly integrated to yield the position of the device. With this approach, a user's gesture input trajectories can be recovered without any external sensors. Three versions of motion tracking algorithms are provided to cope with wide spectrum of applications. Then, a Bayesian network based recognition system processes the recovered trajectories to identify the gesture class. Experimental results convincingly show the feasibility and effectiveness of the proposed gesture input device. In order to show practical use of the proposed input method, we implemented a prototype system, which is a gesture-based remote controller (Magic Wand).

• Korean Institute of Interior Design Journal
• /
• v.26 no.6
• /
• pp.53-61
• /
• 2017

Cityschumers experience the urban with the visual perception while walking an average speed of 4km per hour. At this time, recognition of the color field accounts for more than 70%. Therefore, in this paper the environmental color of urban street is examined by dividing the pedestrian visual field area. In the urban street, the area of the visual field area of the pedestrian is divided into Ground Plane, Roadside, Canopy and Building Wall. In addition, we observe and color survey the environmental color of Exhibition Road, which is the northern side space of South Kensington in London, which adopted the world's first shared space. The color of the visual filed area was dominated as YR, GY, Y, PB. The Ground Pland was dominated by the YR. The reason for this is that the color of the floor has changed due to the shadows of surrounding architecture and facilities. Roadside was dominated in various ways such as GY, BG, PB, B and P. Canopy was mainly composed of PB, GY, etc. It was found that the material color of the lower part of the architecture was reflected. The architecture wall was affected by the reflectance and absorption rate of the transparent material. The first image that comes to mind when thinking about the urban is the street where pedestrians walk, feel and enjoy themselves. Therefore, it is suggested that various policy frameworks for managing and managing urban planning professionals may be different from the perceptions of pedestrians active in mega cities.

• Proceedings of the KIEE Conference
• /
• 2000.07d
• /
• pp.2843-2845
• /
• 2000

A lane detection based on a road model or feature all need correct acquirement of information on the lane in a image, It is inefficient to implement a lane detection algorithm through the full range of a image when being applied to a real road in real time because of the calculating time. This paper defines two searching range of detecting lane in a road, First is searching mode that is searching the lane without any prior information of a road, Second is recognition mode, which is able to reduce the size and change the position of a searching range by predicting the position of a lane through the acquired information in a previous frame. It is allow to extract accurately and efficiently the edge candidates points of a lane as not conducting an unnecessary searching. By means of removing the perspective effect of the edge candidate points which are acquired by using the inverse perspective transformation, we transform the edge candidate information in the Image Coordinate System(ICS) into the plane-view image in the World Coordinate System(WCS). We define linear approximation filter and remove the fault edge candidate points by using it This paper aims to approximate more correctly the lane of an actual road by applying the least-mean square method with the fault-removed edge information for curve fitting.

• Journal of the Korean Society of Costume
• /
• v.54 no.5
• /
• pp.155-166
• /
• 2004

OP-Art was not appreciated by painters and art critics. and according1y has been forgotten in art history. But recently Op-Art is revitalized in fashion and is in its palmy days. This study intends to re-assess the value of Op-Art, by reviewing its influence on fashion design in the post-modern society To this purpose, conceptual characteristics of Op-Art was analyzed. And then, on the bases of these characteristics, the figural characteristics and the meaning of Op-Art in fashion design of post-modern society was re-explained. Op-Art is characterized as an art of flatness of picture plane which uses repetition of simple forms and colors. It is also based on trick of visual perception. Finally. it creates an impression which is flickering or vibrating by means of optical illusion. These characteristics give birth to some features such as simplicity. anonymity and mobility in the Op-Art fashion. The meanings of Op-Art in fashion design in post-modern society are as follows. First, repetition of simple units employed in Op-Art produces feeling of simplicity. which makes the Op-Art fashion works perceived as polysemy. In other words, the feeling of simplicity can be interpreted In diverse perspectives within the social context of our society. The material civilization and technology civilization, which causes the alienation and standardization of man. can be the backgrounds of the Op-Art fashion. Second, Op-Art is an art based on perspectives of spectators. Anonymity in the Op-Art fashion enhances participation of spectators. which gives Op-Art a sense of affinity. Third, through the feeling of mobility created by optical illusion techniques. the Op-Art fashion expresses the opposition to the ideal body image made by power group. In post-modern society, Op-Art in fashion gives new meaning to art. Op-Art in fashion proposes new roles of artist and spectators, and new concepts of art related with roles of human beings. Through general sensibility of men, Op-art in fashion can express new recognition of the post-modern society.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.17 no.5
• /
• pp.1070-1075
• /
• 2013

In this research, we describe a security robot system and ongoing research results to control human's wrong direction in order to forbid human to enter security zone. Proposed robot system surveils a security area with equipped laserscanner sensor usually. When it detect walking human who is for the area, robot calculates his velocity vector, plans own path to forestall and interrupts him who want to head restricted area and starts to move along the estimated trajectory. The walking human is assumed to be a point-object and projected onto an scanning plane to form a geometrical constraint equation that provides position data of the human based on the kinematics of the mobile robot. While moving the robot continues these processes for adapting change of situation. After arriving at an opposite position human's walking direction, the robot advises him not to be headed more and change his course. The experimental results of estimating and tracking of the human in the wrong direction with the mobile robot are presented.

• Land and Housing Review
• /
• v.2 no.4
• /
• pp.407-413
• /
• 2011

This paper reports a novel structural health monitoring (SHM) technique for detecting de-bonding between a concrete beam and CFRP (Carbon Fiber Reinforced Polymer) sheet that is attached to the concrete surface. To achieve this, a multi-scale actuated sensing system with a self-sensing circuit using piezoelectric active sensors is applied to the CFRP laminated concrete beam structure. In this self-sensing based multi-scale actuated sensing, one scale provides a wide frequency-band structural response from the self-sensed impedance measurements and the other scale provides a specific frequency-induced structural wavelet response from the self-sensed guided wave measurement. To quantify the de-bonding levels, the supervised learning-based statistical pattern recognition was implemented by composing a two-dimensional (2D) plane using the damage indices extracted from the impedance and guided wave features.