• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1161_1162
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• 2009

The recent environmental protection trend requires more strict energy saving, therefore every transportation system should reduce energy consumption to the minimum value. High-efficiency operation system, energy saving and $CO_2$ emissions shall be addressed as important issue in railway system. These issues are the most essential factors of railway, compared to major public transportation system. Recently, saving energy in the electric railway system has been studied. For such new energy saving, the energy storage system is considered for saving energy. Energy saving is possible by efficient use of regenerated energy. Regenerated energy is recycled amongst vehicles by mean of charge and discharge corresponding to powering and braking of electric vehicle operations. This energy saving contributes to cut $CO_2$ to reduce greenhouse gas emissions. Recycling regenerated energy demonstrate significant effect on peak cut of consumption energy in railway substation. Absorption of excess energy avoids regeneration failure due to high traction voltage. Therefore, the energy storage system is needed to be adopted to use regeneration energy when the vehicle is braking.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.9 s.186
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• pp.156-163
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• 2006

The purpose of this study is to improve the machining of free-formed NURBS surfaces using newly defined G-codes which can directly deal with shapes defined from CAD/CAM programs on a surface basis and specialize in rough and finish cut. To this purpose, a NURBS surface interpolation system is proposed in this paper. The proposed interpolation system includes online tool-path planning, real-time interpolation and feedrate regulation considering an effective machining method and minimum machining time all suitable for unit NURBS surface machining. The corresponding algorithms are simultaneously executed in an online manner. The proposed NURBS surface interpolation system is integrated and implemented with a PC-based 3-axis CNC milling system. A graphic user interface (GUI) and a 3D tool-path viewer which interprets the G-codes for NURBS surfaces and displays whole tool-paths are also developed and included in our real-time control system. The proposed system is evaluated through actual machining in terms of size of NC data, machining time, regulation of feedrate and cutting force focused on finish cut in comparison with the existing method.

• Journal of the Institute of Electronics and Information Engineers
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• v.49 no.10
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• pp.102-108
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• 2012

The paper proposes an algorithm which finds a nonlinear cut path for a printed grayscale touching character image. The conventional algorithms were observed to fail in situations of complicated touching. We analyzed those situations, and based on the analysis results we identified problematic issues of the conventional algorithms. We modified the conventional algorithms in two aspects. First we propose a new penalizing term which is probable to guide correctly the cut path for touching situations difficult to separate. Second the preposed algorithm adopts a strategy of producing both the downward and upward paths and selecting better one. The experimental results on actual touching character images showed that the proposed algorithm was superior th conventional algorithms by 3~4% in terms of success ratio of separation.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.5
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• pp.1102-1110
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• 2005

In this paper, we proposed a advanced approach to resolve the trade-off problem for the threshold value determining the photo-consistency in the previous algorithms. The threshold value for the surface voxel is substituted the photo-consistency value of the inside voxel. As iterating the voxel coloring process, the threshold is approached to the optimal value for the individual surface voxel. we present an energy minimization formulation of the binary labeling problem that surface voxels classify into opacity or transparency. The energy formula consists of the data term and the smoothness term. As considering neighboring voxels in the labeling problem, the unevenness of reconstructed surface is reduced. The labeling whose energy is the global minimum can be computed using a graph cut.

• Journal of Environmental Impact Assessment
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• v.18 no.6
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• pp.359-366
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• 2009

CCS (Carbon Capture and Storage) is considered as the most promising interim solution to deal with the greenhouse gas such as $CO_2$ responsible for global warming. Even though carefully chosen geologic formations are known to contain stored gas for a long time period, there are potential risks of leakage. Up to now, applicable risk assessment procedures for the leakage of $CO_2$ are not available. This study presents a basis for risk analysis applicable to a complex geologic storage system. It starts with the classification of potential leakage pathways. Receptors and the leakage effect on them are identified and quantified. Then, a fault tree is constructed, which yields the minimum cut set (i.e., the most vulnerable leakage pathway) and quantifies the probability of the leakage risk through the cut set. The methodology will provide a tool for risk assessment in a CCS project. The outcomes of the assessment will not only ensure the safety of the CCS system but also offer a reliable and efficient monitoring plan.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.9
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• pp.85-96
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• 2010

The recent environmental protection trend requires more strict energy saving, therefore every transportation system should reduce energy consumption to the minimum value. High-efficiency operation system, energy saving and $CO_2$ emissions shall be addressed as important issues in railway system. These issues are the most essential factors of railway, compared to major public transportation system. Recently, saving energy in the electric railway system has been studied. The efficient use of regenerated energy is considered to save energy. Namely, Using regenerative energy is that to store the energy generated during braking and discharge it again when a vehicle accelerates. Reusing energy stores and discharges energy, consequently enables a complete exchange of energy between vehicles, even if they are not braking and accelerating at precisely the same time, as is most frequently the case in everyday service. This paper analyzes effects of energy saving and $CO_2$-cut by using regenerative energy of electric vehicles.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.21 no.3
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• pp.151-157
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• 2021

This paper deals with financing an early retirement scheme problem(FERSP) with minimum initial cash and filling up maximum financial interest. For this problem, Guéret et al. programming the Mosel, and Edvall merely realize the CPLEX Branch-and-Cut MIP Solver program to get the optimal solution. But there is no clear rule to finding the solution. This paper suggests calculation formula of bond number decision-making that the reverse from long arrival due date to short. Then we optimize and confirm the bonds number in accordance with continuative effect of the arrival due date. The shortage prepare with the principal and interest of one year deposit(saving) reversely calculation formula.

• International Journal of Naval Architecture and Ocean Engineering
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• v.13 no.1
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• pp.772-785
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• 2021

Container ships has a transverse section in the form of an open profile, making it very sensitive to torsion phenomena. To minimize this effect, a structure known as a torsion box exists, which is subject to high stresses influenced by the fatigue phenomenon and the existence of cut-outs, for the passage of the longitudinal stiffeners, acting as stress concentrators. The aim of this study is to propose a two-stage design methodology to aid designers in satisfying the structural requirements and contribute with to a better understanding of the considered structure. The transverse webs of a torsional box structure are examined by comparing different cut-out geometries from numerical models with different regular load conditions to obtain the variables of the fatigue safety factor through linear regression models. The most appropriate geometry of the torsion box is established in terms of minimum weight, from nonlinear multivariable optimization models.

• The KIPS Transactions:PartB
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• v.18B no.6
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• pp.405-414
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• 2011

Korean grammar checkers typically detect context-dependent errors by employing heuristic rules that are manually formulated by a language expert. These rules are appended each time a new error pattern is detected. However, such grammar checkers are not consistent. In order to resolve this shortcoming, we propose new method for generalizing error decision rules to detect the above errors. For this purpose, we use an existing thesaurus KorLex, which is the Korean version of Princeton WordNet. KorLex has hierarchical word senses for nouns, but does not contain any information about the relationships between cases in a sentence. Through the Tree Cut Model and the MDL(minimum description length) model based on information theory, we extract noun classes from KorLex and generalize error decision rules from these noun classes. In order to verify the accuracy of the new method in an experiment, we extracted nouns used as an object of the four predicates usually confused from a large corpus, and subsequently extracted noun classes from these nouns. We found that the number of error decision rules generalized from these noun classes has decreased to about 64.8%. In conclusion, the precision of our grammar checker exceeds that of conventional ones by 6.2%.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.1
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• pp.89-99
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• 2016

The effects of retail cut type on chemical, quality and nutritional characteristics of horse meat were studied. Jeju female breed horses (n = 9) at 32-mo-old were slaughtered and the carcasses at 24 h post-mortem were fabricated into 10 retail cuts including: tender-loin, loin, strip-loin, shoulder-chuck-roll, shoulder-clod, top-round, outside-round, brisket, short-plate-brisket, and shank. The results revealed that all of parameters (chemical, meat quality and nutritional composition) examined significantly (p<0.05) differed between the cuts. The chemical composition range (minimum to maximum) of cuts was found as such: moisture 65.06% to 71.69%; protein 19.07% to 21.28%; collagen 1.40% to 2.45%; fat 2.56% to 12.14% and cholesterol 55.76 to 79.50 mg/100 g. Shoulder-chuck-roll had the highest pH and water-holding capacity, while top-round had the highest cooking loss. Shear force ranged between the cuts from $2.80kg/cm^2$ to $4.98kg/cm^2$. The Cu, Fe, and Zn contents ranged between the cuts from 1.52 mg/kg to 2.75 mg/kg, 21.25 mg/kg to 30.85 mg/kg, and 16.51 mg/kg to 40.42 mg/kg, respectively. Additionally, most of the cuts studied showed favorable polyunsaturated fatty acid/saturated fatty acid, n-3/n-6 and essential amino acid/non-essential amino acid ratios.