• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.38C no.8
• /
• pp.725-732
• /
• 2013

Recently, various applications for LED lightings are growing continuously due to their better performances such as low power consumption, longer life time, operation speed, controllability, high quality color rendering, and sustainability. However, in developing the high-powered LEDs illumination system, heat-sink problem is one of the important obstacle. In this paper, a heat-sink design with multi-layered structure for high-powered LEDs is proposed, which is composed of metal core PCB, heat-pipes, heat-sink plates, and fans. And also, in this paper, a design for LED controls using DMX512 protocols through RS-485 communications is proposed, which is considered as de facto international standard in LEDs illumination control and is widely used in landscape lighting and stage lighting. In this paper, LED control and its application techniques are introduced and the method of wireless remote control for main controller is proposed.

• Journal of KIISE:Software and Applications
• /
• v.36 no.2
• /
• pp.122-130
• /
• 2009

Conventional approaches for car number plate detection have dealt with those input images having similar sizes and simple background acquired under well organized environment. Thus their performance get reduced when input images include number plates with different sizes and when they are acquired under different lighting conditions. To solve these problem, this paper proposes a new scheme that uses the geometrical features of number plates and their topological information with reference to other features of the car. In the first step, those edges constructing a rectangle are detected and several pixels neighboring those edges are selected as the seed pixels for region growing. For region growing, color and intensity are used as the features, and the result regions are merged to construct the candidate for a number plate if their features are within a certain boundary. Once the candidates for the number plates are generated then their topological relations with other parts of the car such as lights are tested to finally determine the number plate region. The experimental results have shown that the proposed method can be used even for detecting small size number plates where characters are not visible.

• Journal of KIISE:Software and Applications
• /
• v.36 no.4
• /
• pp.291-297
• /
• 2009

This paper introduces an electronic travel aid, named SmartWand, which detects obstacles using a ultrasonic sensor. In addition to obstacle detection, the SmartWand senses color information of objects and the environmental brightness. It is designed to be attached to a ordinary white cane in order to detect the obstacles at head-hight which cannot be covered by the cane. We have improved the first version of the SmartWand based on a user evaluation. The second version is much lighter and smaller than the previous one. It has been enhanced by two new functions. The SmartWand eliminates impact errors due to tapping the ground using a moving average filtering algorithm and restricts the detection range to the path in the moving direction using an acceleration sensor. We have tested these functions in various environments to determine the parameters for these functions.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.6 no.8
• /
• pp.1223-1233
• /
• 2002

Recently various electronic books (I-Book) based on PDA (personal digital assistance) that we can easily use anytime and anywhere have been developed. Volume and weight of the E-Book is much less than that of traditional books. In that reason, it is easy to carry and serve us with contents by diverse functions such as searching, bookmark, dictionary, and playing of color image, sound or moving picture. On account of these advantages, many products connected with I-Book have been emerged in the market. However a product connected with educational contents is scarce, because it requires not only normal function but also additional functions such as a problem solving. Therefore it is actually necessary to develop a browser and an editor for educational contents. In this paper, we express educational contents by XML and define structure of document with XML schema. Then, we design and implement an editor and a browser that can manage educational contents on PDA.

• The KIPS Transactions:PartB
• /
• v.10B no.2
• /
• pp.135-142
• /
• 2003

Robust extraction of 3D object's features, shape and global motion information from 2D image sequence is described. The object's 21 feature points on the pyramid type synthetic object are extracted automatically using color transform technique. The extracted features are used to recover the 3D shape and global motion of the object using stereo paraperspective camera model and sequential SVD(Singuiar Value Decomposition) factorization method. An inherent error of depth recovery due to the paraperspective camera model was removed by using the stereo image analysis. A 30 synthetic object with 21 features reflecting various position was designed and tested to show the performance of proposed algorithm by comparing the recovered shape and motion data with the measured values.

• Agricultural and Biosystems Engineering
• /
• v.1 no.2
• /
• pp.95-99
• /
• 2000

Nondestructive methods such as ultrasonic and magnetic resonance imaging systems have many advantages but still much expensive. And they do not give exact color information and may miss some details. If it is allowed to destruct some biological objects to get interior and exterior informations, constructing 3D image form a series of slices sectional images gives more useful information with relatively low cost. In this paper, a PC based automatic 3D model generator was developed. The system was composed of three modules. The first module was the object handling and image acquisition module, which fed and sliced the object sequentially and maintains the paraffine cool to be in solid state and captures the sectional image consecutively. The second one was the system control and interface module, which controls actuators for feeding, slicing, and image capturing. And the last was the image processing and visualization module, which processed a series of acquired sectional images and generated 3D volumetric model. Handling module was composed of the gripper, which grasped and fed the object and the cutting device, which cuts the object by moving cutting edge forward and backward. sliced sectional images were acquired and saved in a form of bitmap file. 2D sectional image files were segmented from the background paraffine and utilized to generate the 3D model. Once 3-D model was constructed on the computer, user could manipulated it with various transformation methods such as translation, rotation, scaling including arbitrary sectional view.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.31 no.4C
• /
• pp.417-425
• /
• 2006

This Paper Proposes a method of building a panoramic video from several videos captured from adjacent cameras. The panoramic image which constructed from adjacent and overlapped images is used for photogrammetry, satellite photo or many computer graphic applications. The perspective transformation, which is estimated from the appropriate corresponding pairs of images, can be used to construct the panoramic image without unwarranted distortion and its quality is decided by how to find the features needed for transform estimation. We used the corner points for the corresponding features, and morphological structures were utilized for fast and robust corner detection. We used the criterion of the corner strength, which guarantees the robust detection of the corner in most situations. For the transformation, 8 parameters were estimated from perspective equations which use matched points of adjacent images, and bilinear color blending was used to construct a soapless panoramic video. The experiments showed that the proposed method yields fast results with good quality under various conditions.

• Journal of Internet Computing and Services
• /
• v.21 no.5
• /
• pp.49-56
• /
• 2020

Detecting shadows in images and restoring or removing them was a very challenging task in computer vision. Traditional researches used color information, edges, and thresholds to detect shadows, but there were errors such as not considering the penumbra area of shadow or even detecting a black area that is not a shadow. Deep learning has been successful in various fields of computer vision, and research on applying deep learning has started in the field of shadow detection and removal. However, it was very difficult and time-consuming to collect data for network learning, and there were many limited conditions for shooting. In particular, it was more difficult to obtain shadow data from buildings and satellite images, which hindered the progress of the research. In this paper, we propose a method for generating shadow data from buildings and satellites using Unity3D. In the virtual Unity space, 3D objects existing in the real world were placed, and shadows were generated using lights effects to shoot. Through this, it is possible to get all three types of images (shadow-free, shadow image, shadow mask) necessary for shadow detection and removal when training deep learning networks. The method proposed in this paper contributes to helping the progress of the research by providing big data in the field of building or satellite shadow detection and removal research, which is difficult for learning deep learning networks due to the absence of data. And this can be a suboptimal method. We believe that we have contributed in that we can apply virtual data to test deep learning networks before applying real data.

• Journal of KIISE:Software and Applications
• /
• v.32 no.6
• /
• pp.570-579
• /
• 2005

Facial expression recognition technology that has potentialities for applying various fields is appling on the man-machine interface development, human identification test, and restoration of facial expression by virtual model etc. Using sequential facial images, this study proposes a simpler method for detecting human facial expressions such as happiness, anger, surprise, and sadness. Moreover the proposed method can detect the facial expressions in the conditions of the sequential facial images which is not rigid motion. We identify the determinant face and elements of facial expressions and then estimates the feature regions of the elements by using information about color, size, and position. In the next step, the direction patterns of feature regions of each element are determined by using optical flows estimated gradient methods. Using the direction model proposed by this study, we match each direction patterns. The method identifies a facial expression based on the least minimum score of combination values between direction model and pattern matching for presenting each facial expression. In the experiments, this study verifies the validity of the Proposed methods.

• Journal of the Korea Society of Computer and Information
• /
• v.16 no.6
• /
• pp.179-186
• /
• 2011

This paper suggests the minimum number of vertex guards algorithm. Given n rooms, the exact number of minimum vertex guards is proposed. However, only approximation algorithms are presented about the maximum number of vertex guards for polygon and orthogonal polygon without or with holes. Fisk suggests the maximum number of vertex guards for polygon with n vertices as follows. Firstly, you can triangulate with n-2 triangles. Secondly, 3-chromatic vertex coloring of every triangulation of a polygon. Thirdly, place guards at the vertices which have the minority color. This paper presents the minimum number of vertex guards using dominating set. Firstly, you can obtain the visibility graph which is connected all edges if two vertices can be visible each other. Secondly, you can obtain dominating set from visibility graph or visibility matrix. This algorithm applies various art galley problems. As a results, the proposed algorithm is simple and can be obtain the minimum number of vertex guards.