• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.11
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• pp.1486-1494
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• 2021

Character recognition is a technology required in various platforms, such as smart parking and text to speech, and many studies are being conducted to improve its performance through new attempts. However, with low-quality image used for character recognition, a difference in resolution of the training image and test image for character recognition occurs, resulting in poor accuracy. To solve this problem, this paper designed an end-to-end learning neural network that combines image super-resolution and character recognition so that the character recognition model performance is robust against various quality data, and implemented an alternative whole learning algorithm to learn the whole neural network. An alternative end-to-end learning and recognition performance test was conducted using the license plate image among various text images, and the effectiveness of the proposed algorithm was verified with the performance test.

• Journal of Korean Neurosurgical Society
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• v.30 no.4
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• pp.493-500
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• 2001

Objective : Anterior cervical locking plates are the devices for achieving anterior cervical spinal fusion. This study was conducted to evaluate the locking plate system regarding its long-term advantages and disadvantages in the view of interbody fusion rate, hardware-related failures, vertebral change close to the fusion segment and postoperative complications. Method : Eight-six patients, operated from Jan., 1996 to Jun. 1998, were followed-up for more than two years. All of the cases were fused with iliac bone graft and ORION locking plate(Sofamor Danek USA, Inc., Memphis, TN) fixation. The patients were discharged or transferred to rehabilitation department 2-7 days after operation. A comprehensive evaluation of the interbody fusion state, instrument failure, vertebral change and postoperative complications were made by direct interview and cervical flexion-extension lateral plain films. Results : There were 55 male and 31 female with a mean age of 45 years(18-75 years). The mean follow-up period was 29 months(24-43 months). Various disorders that were operated were 40 cervical discs, 6 cervical stenosis including OPLL, 2 infections, and 38 traumas. Fusion level was single in 59 cases, two levels of each disc space in 15 cases, and two levels after one corpectomy in 12 cases. There was no instrument failure. Pseudoarthrosis was observed in two cases(2%) without radiological instability. The other patients(98%) showed complete cervical fusion with stable instrument. Mild settling of interbody graft with upward migration of screws was found in 12 cases(14%). Anterior bony growth at the upper segment was found in 5 cases(6%). Postoperative foreign body sensation or dysphagia was observed in 12 cases(4%), and disappeared within one month in 7 cases and within six months in 4 cases. One patient complained for more than six months and required reoperation to remove paraesophageal granulation tissue. Conclusion : The results show that Orion cervical locking plate has some disadvantages of upward migration of screws, anterior bony growth at the upper segment, or possibility of esophageal compression even though it has advantages of high interbody fusion rate or low instrument failure. Author believe that anterior cervical locking plate in the future should be thinner, and should have short end from the screw hole, and movable screw with adequate stability.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.05a
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• pp.130-134
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• 2006

The injection uniformity of the fuel manifold in a liquid rocket engine has been analyzed with dividing plates to improve the cooling performance at the face plate. Three dimensional computational fluid dynamics analysis has been performed to compare the injection uniformity for 5 candidate designs and has been verified to compare with the measured data for the optimal manifold design. For the case I and II, the coolant mass flux increases as the whole working fluid is enforced to flow under the dividing plate. The injection uniformity decreases due to the variation of mass flux at the end of dividing plate and the concentration of mass flow rate at the center of manifold. However case III and IV have uniform injection performance due to reduced mass flux concentration as the coolant can flow along both upper passage and lower passage of the dividing plate. Among the candidate designs, case IV is thought to be the optimal dividing plate with regard to cooling performance and injection uniformity.

• Korean Journal of Community Nutrition
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• v.18 no.5
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• pp.505-514
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• 2013

Effect of Menu Calorie Labels on Menu Sales and Consumer's Recognition at a Korean Restaurant in a Hotel The role of calorie information is to help consumers make healthier food choices. However, calorie information is generally unavailable in restaurants. Even in high-end hotel restaurants, which try to provide high quality foods and service, calorie labeling is not mandatory. Therefore, the purpose of this study was to evaluate the effect of calorie labeling on menu sales and consumer's recognition at a Korean restaurant in Kangwonland hotel. The calorie contents of 10 dishes sold in the restaurant were calculated using the food composition table. After making a new menu plate displaying calorie information, the new menu plate and old menu plate were provided every other week for 4 weeks. When we compared the sales between the periods of calorie labeled and calorie unlabeled, sales of 4 items among the 5 food items providing less than 1000 kcal, increased, however the 3 items among the menu providing more than 1000 kcal decreased. As the survey results of total 405 consumers (male n = 232, female n = 173) showed the new menu plate, 68.2% of subjects recognized calorie labeling on the menu plate. Among the subjects who recognized calorie labeling, 58.3% answered that calorie information affected their food choices. And most of them answered that they chose lower calorie foods based on the information provided. The results suggest that displaying calorie information on the menu plate at a Korean restaurant was effective in changing consumer's food choices.

• Steel and Composite Structures
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• v.22 no.6
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• pp.1417-1443
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• 2016

Cellular and castellated steel beams are used to obtain higher stiffness and bending capacity using the same weight of steel. In addition, the beam openings may be used as a pass for different mechanical fixtures such as ducts and pipes. The aim of this study is to investigate the effect of different parameters on both elastic and inelastic critical buckling stresses of steel web plates with openings. These parameters are plate aspect ratio; opening shape (circular or rectangular); end distance to the first opening; opening spacing; opening size; plate slenderness ratio; steel grade; and initial web imperfection. The web/flange interaction has been simplified by web edge restraints representing simply supported boundary conditions. A numerical parametric study has been performed through linear and nonlinear finite element (FE) models, where the FE results have been verified against both experimental and numerical results in the literature. The web plates are subject to in-plane linearly varying compression with different loading patterns, ranging from uniform compression to pure bending. A buckling stress modification factor (${\beta}$-factor) has been introduced as a ratio of buckling stress of web plate with openings to buckling stress of the corresponding solid web plate. The variation of ${\beta}$-factor against the aforementioned parameters has been reported. Furthermore, the critical plate slenderness ratio separating elastic buckling and yielding has been identified and discussed for two steel grades of DIN-17100, namely: ST-37/2 and ST-52/3. The FE results revealed that the minimum ${\beta}$-factor is 0.9 for web plates under uniform compression and 0.7 for those under both compression and tension.

• Steel and Composite Structures
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• v.42 no.2
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• pp.277-288
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• 2022

A novel flat steel plate-concrete-corrugated steel plate (FS-C-CS) sandwich panel was proposed for resisting impact load. The failure mode, impact force and displacement response of the FS-C-CS panel under impact loading were studied via drop-weight impact tests. The combined global flexure and local indentation deformation mode of the FS-C-CS panel was observed, and three stages of impact process were identified. Moreover, the effects of corrugated plate height and steel plate thickness on the impact responses of the FS-C-CS panels were quantitatively analysed, and the impact resistant performance of the FS-C-CS panel was found to be generally improved on increasing corrugated plate height and thickness in terms of smaller deformation as well as larger impact force and post-peak mean force. The Finite Element (FE) model of the FS-C-CS panel under impact loading was established to predict its dynamic response and further reveal its failure mode and impact energy dissipation mechanism. The numerical results indicated that the concrete core and corrugated steel plate dissipated the majority of impact energy. In addition, employing end plates and high strength bolts as shear connectors could prevent the slip between steel plates and concrete core and assure the full composite action of the FS-C-CS panel.

• Transactions of Materials Processing
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• v.22 no.2
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• pp.80-85
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• 2013

The surface integrity of micro-machined products affects the performance of products significantly. Micro-burrs resulting from micro-cutting degrades the surface quality. Therefore it is desired to eliminate them completely and many studies have been undertaken for this purpose. In this study, micro-end-milling was carried out on nickel alloy and brass materials commercially used for light guide plate mold in 3-D optical devices. After completing this micro-machining, the burr heights were measured with a microscope. Then, deburring was done on the machined edges using the MR jet polishing method. A jet angle of $0^{\circ}$ and deburring times of 1, 3, and 5 min. were chosen. It was found that burrs were completely eliminated after 5 min of MR fluid jet polishing.

• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1416-1418
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• 1994

Expressions for the displacement of a bimorph, one end fixed and the other free, has been introduced when sinusoidal inputs were applied to the ceramic plates on a thin metal plate. Maximum displacements at the free end and strains at the position of strain gage attached were measured when various wave forms, voltages, and frequencies were applied to the bimorph whose length is 6.6[cm], width 2.5[cm], and thickness 0.0365[cm]. Under the constant voltage ( $70[V_{peak}]$ ), the strains and the displacements at the free end were larger than the case of the sinusoidal input when the square wave was applied and were smaller when triangular wave. It was shown that the displacements at the free end and the strains of the gage position were increased as the applied voltage in the range of $30-90[V_{peak}]$ and effective length were increased. And it was also found that the resonant frequency of a bimorph was decreased as its effective length was increased, and that the displacements and the strains were maximum at the resonant frequency.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.12
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• pp.80-86
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• 2020

With the exception of welding activities, it is forbidden to use electricity in shipyards, owing to safety concerns such as the possibility of fire, explosions, and short circuits. In this paper, an automatic chamfering machine using pneumatics is proposed for use in such environments. Customers specify their requirements and the machine derives the corresponding theoretical design conditions. The proposed machine was used to perform 3D modeling, and its suitability and performance were confirmed via cutting experiments of the manufactured device. Two types of sensors may be used in this system: contact and non-contact. In the case of the contact type, an end-stop switch that can recognize the end of the material is installed, and when the machine reaches the end of the material, the end-stop switch is operated to cut off the air pressure. In the non-contact type, four sensors were used: photonic, ultrasonic, metal detection, and encoder. The use of the four sensors was repeated 30 times, and the average error determined. Thus, the optimum sensor was identified.

• The Journal of the Acoustical Society of Korea
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• v.27 no.8
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• pp.395-402
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• 2008

In viol family string instruments vibration of string is transmitted to the front plate through bridge to cause resonance of the instrument body. Therefore, the vibration of string is the source of sound and the properties, the structure, and the boundary conditions of string are expected to have significant effect on the sound. In this study the vibration of strings in cello when one end is fixed and the other end is pressed with finger tip is studied and compared with the case of the fixed-fixed ends. The result of analysis and experiment shows that the vibration of the string that is fixed at one end and pressed with finger tip at the other end is significantly influenced by the contact condition of the string with the finger tip and also quite different from that of the fixed-fixed string, It also suggests that the sound of a cello can be significantly influenced by the contact condition between the string and the finger tip in the fingered string.