• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.2
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• pp.821-831
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• 2013

As a result of recent research, it is reported that the periodic replacements criterion of rails is able to extend as grinding rail surface and using the continuous welded rail (CWR). In this study, we carried out fatigue tests on existing laid rails. Based on the test results, an S-N curve expressing the remaining life of laid rails at a fracture probability of 50% was obtained using weighted probit analysis suitable for small-sample fatigue data sets. As rails used for testing had different histories in terms of accumulated tonnage, the test data were corrected to average out the accumulated tonnage. We estimated the remaining service lives for laid rails on the urban railway using equations developed in the past to estimate rail base bending stress and that surface irregularities into consideration. Therefore, estimating the remaining service life of laid rails showed that the rail replacement period could be extended over 200 MGT, although it is necessary to remove longitudinal rail surface irregularities at welds by grinding. Also, the fatigue test results under fatigue limit, Haibach's rule appling half slope of S-N curve under the fatigue limit was considered more reasonable than modified Miner's rule for estimating rail fatigue life.

• Fiber Technology and Industry
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• v.12 no.2
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• pp.88-95
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• 2008

• IEMEK Journal of Embedded Systems and Applications
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• v.3 no.2
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• pp.66-73
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• 2008

The pipes have been laid underground while the industry is developing. We have to take maintenance procedure when the pipes are cracked or ruptured. It is very difficult jop to check pipe's crack because the pipes are narrow and laid underground. Using in-pipe robot, we can check the conditions of inner section of pipes, therefore, we designed a crawler type robot to search cracked pipe. In this paper, we have made a special focus on the control of the robot using differential drive algorithm to move in curved section of pipes. The detailed design of the robot with experimental result show the effectiveness of the robot in pipe maintenance.

• Research in Mathematical Education
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• v.12 no.4
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• pp.293-299
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• 2008

Young children have manifold potentialities. As any teacher or parent knows, a child's most obvious strengths contribute to their development in unexpected ways. A sporting or musical forte may provide an invaluable youthful opportunity to experience "the pursuit of excellence," but may then be laid aside. It is exceedingly rare for a strength which informed observers might "identify" at school level to develop in a predictable way. Most strengths blossom and are then laid aside, whilst some evolve sideways (for example, when the inner muse shies away from the required level of commitment, or takes fright at the miniscule prospects of success in the given field). In their place other strengths-which one may have noticed, but which were never "diagnosed" in the same way-take over and flourish.

• Journal of Chest Surgery
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• v.24 no.6
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• pp.560-569
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• 1991

The surgical management of symptomatic tetralogy of Fallot in infants is debatable. From November 1986 to August 1990, 21 infants under 10 kg of the body weight with tetralogy of Fallot underwent primary repair. Mean body weight was 8.6$\pm$1.40kg. All the patient were clubbing and there were cyanotic except for 1 patient. Transannular patch was laid down in 8 patients. Right ventricular outflow patch was used with Goretex but pericardial patch was utilized in 3 patients at the initial period of operation. Incidence of the complications following total correction of tetralogy of Fallot was more frequent in the patients placed with transannular patch compared to the patients with right ventricular outflow tract patch. Two deaths occurred in the 21 patients, Hospital mortality was 9.4%, but there were no operative deaths in the patients who transannular patch was laid down. Causes of deaths were low cardiac output.

• Journal of Sericultural and Entomological Science
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• v.7
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• pp.39-42
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• 1967

The author studied on the eggs laying order of silkworm eggs which was laid by double copulation. The results can be summarized as follows; 1. Fertilized eggs were not laid in order like the copulating order. Author supposes that the sperms of the first copulated moth and second's moth were mixed in the receptaculum seminis. 2. Intensity of fertilization was mainly affected by silkworm races and copulating order, but some other factors may be acted on the double copulation.

• Korean Journal of Computational Design and Engineering
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• v.16 no.3
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• pp.207-215
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• 2011

Due to its large size, a ship is first divided into scores of blocks and then each block is constructed through various shops, such as the assembly shop, the painting shop, and the outfitting shop. However, each block may not be directly moved to the next shop and may be temporarily laid on a block stockyard because the working time in each shop is different. If blocks are laid on the block stockyard without any planning, the rearrangement of the blocks by a transporter are required because the blocks have the different in and out time. In this study, an optimal layout method based on the genetic algorithm was proposed in order to minimize the rearrangement of the blocks in the block stockyard. To evaluate the applicability of the proposed method, it was applied to a simple layout problem of the block stockyard.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.81-84
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• 2008

The purposes of this study are to verify a reasonable model of material characteristic and to propose a rational model of reinforcement characteristic considering monotonic and cyclic loading about manufactured reinforcing steel in Korea. Longitudinal reinforcements of the plastic hinge region were behaved tensile deformation and compressional deformation by direction of lateral loading. However Confinement steels were behaved only tensile deformation by lateral loading. Transverse steels were laid the state of tension in the lateral loading of time, and they were laid state that stress is zero when it was removed lateral load. The tests for cyclic tension loading were performed for test variable as yield strength and reinforcement bar sizes. It was estimated that the total strain energy per unit volume was 74 $MJ/m^3$. The modified ultimate concrete compression strain model was proposed based on experimental study of cyclic tension test for manufactured reinforcing steel in Korea.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1996.06c
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• pp.1090-1100
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• 1996

Heating floor is the most profitable system of air heating at poultry houses. THe tubes with heating elements inside are laid into the layer of concrete. To prevent lossese of heat penetration deep into the ground the layer of isolation material is laid below the tubes . The depth of isolation laying in every point of the heating floor may be calculated according to the author's formula using the data of temperature on the floor surface and the tube, the distance between tow nearest tubes, and the distance between the tube and the floor surface. Technological investigations allow to estimate the optimal density for greese and ducks when they are bred on the heatuing floor.

• Journal of the Korean Society of Tobacco Science
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• v.18 no.2
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• pp.113-119
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• 1996

The ovipositional responses of two strains of the cigarette beetle, Lasioderma serricorne F., to thickness, of air- and flue-cured leaf tobacco were investigated. Eggs laid by the strains reared with wheatflour (95%) + yeast (5%) in the laboratory for several years were not different between air - and flue-cured tobacco leaves. There were negative correlations between grades of cured tobacco and ovipositional response, and the regression equation was Y(ovipositional response) : 58.22 - 10.15X(leaf grade). Adults of strains reared on tobacco leaves laid 161.00±80.29 eggs on the first grade of thick flue-cured leaves, and 7.67 ± 5.51 on the second grade of thin air-cured leaves. There was difference in ovipositional responses among different grades within variety, but significant differences were noted between thick and thin tobacco leaves. Key words : ovipositional response, cigarette beetle, Lasiodema sewicome F., tobacco.