• Journal of IKEEE
• /
• v.6 no.1 s.10
• /
• pp.94-101
• /
• 2002

In this paper, we propose a motion estimation algorithm for the discontinuity blocks. The algorithm uses sub-SAD value (i.e. the sum of absolute difference for a quarter of a block) to identify the discontinuity region, and produces additional motion vectors for these sub-blocks if necessary. We show with experimental results that, in comparison with some conventional motion estimation algorithms, the proposed algorithm achieves quality enhancement for the sequences with discontinuity blocks, and also shows the same computational quantity as to normal algorithms for sequences with less discontinuity.

• International Journal of Naval Architecture and Ocean Engineering
• /
• v.10 no.4
• /
• pp.450-457
• /
• 2018

The determination of assembly sequence in general mechanical assemblies plays an important role in terms of manufacturing cost, duration and quality. In the production of ships and offshore plants, the consideration of productivity factors and welding deformation is crucial in determining the optimal assembly sequence. In shipbuilding and offshore industries, most assembly sequence planning has been done according to engineers' decisions based on extensive experience. This may result in error-prone planning and sub-optimal sequence, especially when dealing with unfamiliar block assemblies composed of dozens of parts. This paper presents an assembly sequence planning method for block assemblies. The proposed method basically considers geometric characteristics of blocks to determine feasible assembly sequences, as well as assembly process and productivity factors. Then the assembly sequence with minimal welding deformation is selected based on simplified welding distortion analysis. The method is validated using an asymmetric assembly model and the results indicate that it is capable of generating an optimal assembly sequence.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.12 no.7
• /
• pp.3239-3267
• /
• 2018

Image and video dehazing is a popular topic in the field of computer vision and digital image processing. A fast, optimized dehazing algorithm was recently proposed that enhances contrast and reduces flickering artifacts in a dehazed video sequence by minimizing a cost function that makes transmission values spatially and temporally coherent. However, its fixed-size block partitioning leads to block effects. The temporal cost function also suffers from the temporal non-coherence of newly appearing objects in a scene. Further, the weak edges in a hazy image are not addressed. Hence, a video dehazing algorithm based on well designed spectral clustering is proposed. To avoid block artifacts, the spectral clustering is customized to segment static scenes to ensure the same target has the same transmission value. Assuming that edge images dehazed with optimized transmission values have richer detail than before restoration, an edge intensity function is added to the spatial consistency cost model. Atmospheric light is estimated using a modified quadtree search. Different temporal transmission models are established for newly appearing objects, static backgrounds, and moving objects. The experimental results demonstrate that the new method provides higher dehazing quality and lower time complexity than the previous technique.

• Culinary science and hospitality research
• /
• v.8 no.2
• /
• pp.59-76
• /
• 2002

After 1990, Food service industry is growing up so fast and asking a lot of employee to be able to work this one. Our society will continue the growth of quantity and quality of food service industry with closing to the developed country and increasing the national income and leisure time. But our present culinary education system cannot gain the efficient of professional training to adopt food service industry without re-education and training. So, in our culinary education we have to be introduced new education system which is used effectively as a professional culinary education system in C.I.A. This system has merit to be able to teach step by step from basic to advanced course. Also Most of school system(management purchasing, human research, school life, etc.) is focused for culinary education. But, although this system has a lot of merits, it is too early toy us to adopt in our culinary education system. Because our education system has too much limited educational administrations of government and school for introducing new education system. The present educational situation is not enough to have facilities and financial support Finally, our culinary educational system have to change to right direction to improve in culinary education. Block system is one of the well-prepared system. But we need to administrational support of government and school to be able to adopted to our culinary educational system.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.10 no.5
• /
• pp.2326-2345
• /
• 2016

For the compression of color images, a common bitmap usually is generated to replace the three individual bitmaps that originate from block truncation coding (BTC) of the R, G and B channels. However, common bitmaps generated by some traditional schemes are not the best possible because they do not consider the minimized distortion of the entire color image. In this paper, we propose a near-optimized common bitmap scheme for BTC using Binary Ant Colony Optimization (BACO), producing a BACO-BTC scheme. First, the color image is compressed by the BTC algorithm to get three individual bitmaps, and three pairs of quantization values for the R, G, and B channels. Second, a near-optimized common bitmap is generated with minimized distortion of the entire color image based on the idea of BACO. Finally, the color image is reconstructed easily by the corresponding quantization values according to the common bitmap. The experimental results confirmed that reconstructed image of the proposed scheme has better visual quality and less computational complexity than the referenced schemes.

• Special Issue of the Society of Naval Architects of Korea
• /
• 2008.09a
• /
• pp.118-125
• /
• 2008

The deck plates of ship block is made of thin plates in their construction. A main reason of using thin plates is that deck plates don't need to support large structural loads. Therefore, out-of-plane deformations between stiffeners are frequent in deck blocks. Because these are got right by correction heating, they continuously causes quality problems in the final dock-building process. According to preceding research, the lifting process by cranes would offset the effect of correction heating. This study finds out the remained efficiency of correction heating when tensional loads are added by a lifting to corrected parts. We used inherent strains in calculating the efficiency, and established the methodology where the positions for callings are. For getting more accurate positions, besides the structural lifting analysis, welding deformation analysis with upper block and measured data from a serial ship are also referenced.

• 연구논문집
• /
• s.28
• /
• pp.229-238
• /
• 1998

Materials and parts required for nondestructive testing should be evaluated using with standard block. And it is ruled that standard blocks should be fabricated from same or similar material with test specimen. In order to manufacture and export materials and parts, quality assurance system should be required. In this paper, ultrasonic characteristics of ASTM 4340 steel ultrasonic standard block are investigated for nondestructive evaluation of udimet 720Li disc. Microstructures of udimet 720Li alloy are investigated using with optical and transmission electron microscope. Also ultrasonic transit time and attenuation are measured from high power ultrasonic analysis system with phase adjustment method. Conclusively, it is proved that 4340 steel ultrasonic standard block can be use for nondestructive evaluation of udimet 720Li disc.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.10 no.6
• /
• pp.146-151
• /
• 2011

Wax spin coating is a part of several wafer handling processes in the silicon wafer polishing station. It is important to ensure the wax layer free of contamination to achieve the high degree of planarization on wafers after wafer polishing. Three-dimensional air flow characteristics in a wax spin coater are numerically investigated using computational fluid dynamics techniques. When the bottom of the wax spin coater is closed, there exists a significant recirculation zone over the rotating ceramic block. This recirculation zone can be the source of wax layer contamination at any rotational speed and should be avoided to maintain high wafer polishing quality. Thus, four air suction ducts are installed at the bottom of the wax spin coater in order to control the air flow pattern over the ceramic block. Present computational results show that the air suction from the bottom is quite an effective method to remove or minimize the recirculation zone over the ceramic block and the wax coating layer.

• The Journal of Natural Sciences
• /
• v.7
• /
• pp.67-73
• /
• 1995

In this paper, a new texture segmentation-based image coding technique which performs segmentation based on properties of the human visual system (HVS) is presented. This method solves the problems of a segmentation-based image coding technique with constant segments by proposing a methodology for segmenting an image into texturally homogeneous regions with respect to the degree of roughness as perceived by the HVS. The segmentation is accomplished by thresholding the fractal dimension so that textural regions are classified into three texture classes; perceived constant intensity, smooth texture, and rough texture. It is very important to determine the proper block size for estimating the fractal dimension. Good quality reconstructed images are obtained with about 0.1 to 0.25 bit per pixel (bpp) for many different types of imagery.

• Journal of the Korea Concrete Institute
• /
• v.13 no.2
• /
• pp.87-92
• /
• 2001

Until now, disposal of casting foundry fly ash generally depends on reclamation. This is the great loss from a point of view saving of resources and utilizing industrial wastes. Therefore, a study on the use of fly ash as a substitute material for construction is necessary in order to utilize industrial wastes, to reduce cost of production, to improve quality in producing concrete products, and to protect environment from pollution. In this study, concrete products(hollow concrete block and concrete brick) using casting foundry fly ash as a substitute materials for cement, are produced. And experiments are conducted based on Korean Industrial Standards. Finally, the used methods of casting foundry fly ash as a substitute materials in industry are presented.