• International Journal of Precision Engineering and Manufacturing
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• v.9 no.1
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• pp.47-50
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• 2008

This paper presents a new water-lubricated hybrid sliding bearing for a high speed and high accuracy main shaft system, along with the numerical method used for its design. The porous material for the restrictor and the restriction parameter were chosen based on the special requirements of the water-lubricated bearing. Subsequent numerical calculations give the load capacity, stiffness, and friction power of different forms of water-lubricated bearings. The pressure distribution of the water film in a 6-cavity bearing is shown, based on the results of the numerical calculations. A comparison of oil-lubricated and water-lubricated bearings shows that the latter benefits more from improved processing precision and efficiency. An analysis of the stiffness and friction power results shows that 6-cavity bearings are the preferred type, due their greater stiffness and lower friction power. The average elevated temperature was calculated and found to be satisfactory. The relevant parameters of the porous restrictor were determined by calculating the restriction rate. All these results indicate that this design for a water-lubricated bearing meets specifications for high speed and high accuracy.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.05a
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• pp.749-750
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• 2013

Due to the rapid development of smart phones, smart phone users grew, expanding communication between the service users has been enabled by the application's service. Difficult to find a service that allows you to know the quality of school meals and the expectations of these applications. In addition, the existing application works only with a particular device, it is difficult to compatible devices. Thus, based on the HTML5 hybrid application were developed and this feed can be monitored by the students of the school, the communication can be formed.

• The Journal of Korean Association of Computer Education
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• v.10 no.5
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• pp.53-60
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• 2007

To enhance learning efficiency, we implement a hybrid experimental system for electrical and electronic circuits where web-based virtual laboratory system and distant education system are properly integrated. In the first stage, we developed web-based virtual laboratory systems for electrical/electronic circuit experiments, which are composed of three important sessions and their management system: concept learning, virtual experiment, assessment. In the second stage, we have implemented cost-effective distant laboratory systems for practicing electric/electronic circuits, which can be used to eliminate the lack of reality occurred during virtual laboratory session. The proposed virtual/ distant laboratory systems can be used in stand-alone fashion, but to enhance learning efficiency we integrated them and developed a creative hybrid experimental system for electric and electronic circuits.

• The Journal of Korean Institute for Practical Engineering Education
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• v.4 no.2
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• pp.53-59
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• 2012

This article reviews the current issues of engineering education: engineering creativity, R&D 3.0 and Education 3.0 and comfirms need of refining quality of engineering education through learner-centered hybrid project learning. this article suggests the Global engineering project(GEP) program as an ideal hybrid project learning model that develop student's creativity and convergence capability. GEP program is learnner-centered interdisciplinary program that whole processes are managed by interdisciplinary students team aiming to global engineers who are globally competent and locally relevant so that they can function effectively in any country by local activity in developing country. The program consist of four main parts: 1)pre activity, 2)local activity from abroad, 3)design and producing prototype and 4)participating in the design contest or academic conference with the products. As a result, students' global competence, teamwork skill and capability of creative problem solving are remarkably improved.

• The Journal of Korean Association of Computer Education
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• v.12 no.3
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• pp.31-40
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• 2009

English education taken with native English speakers is very effective, but it is hard to obtain English education with native English speakers in rural schools. In this study, therefore, we supported English education with on-line content and video conferencing with native English speakers. This study worked with one hundred fifty students from six elementary and middle schools equally distributed by city size over three months. This study performed experimental research by T-test comparing of pre- and post-tests of the hybrid model. In our results, the upper group showed greater improvement in understanding while the lower group showed more improvement in writing. In addition, the lower group showed more improvement than the upper group in overall English accomplishment.

• The Journal of Korean Institute for Practical Engineering Education
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• v.3 no.2
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• pp.100-105
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• 2011

By adopting HIL(Hardware-in-the-Loop), component characteristics in vehicle environment can be obtained without implementing component in the vehicle. In this paper, when specific motor is adopted as traction motor in hybrid electric vehicle HIL implementation procedures are explained. In order to implement HIL method motor testing. vehicle performance simulator and load characteristic are explained. Vehicle controller used in simulator is directly uploaded in real controller. Especially as a load dynamometer actively controlled motor system is used without connecting conventional mechanical inertia. Motor characteristics are obtained using HIL implementation when test motor is used as a traction motor for parallel hybrid electric vehicle. Proposed method can be used as experimental equipment to educate driving characteristics of hybrid electric vehicle.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.8
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• pp.3983-3991
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• 2013

Census transform is one of the stereo vision methods which is robust to radiometric distortion and illuminance change. This paper proposes a hybrid census transform using the mini census transform and the generalized census transform concurrently. This method uses simplicity of mini census transform and noise feature of generalized census transform together. This paper performed stereo matching containing post processing to evaluate each methods. The result shows that hybrid census transform has similar performance to generalized census transform and mean value of calculation complexity between mini census transform and generalized census transform.

• Journal of the Korean Institute of Intelligent Systems
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• v.23 no.6
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• pp.487-493
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• 2013

As the spread of smart devices that service variety of content, limited mobile terminal channel assignment problem has intensified. In the channel assignment in mobile networks mobile switching center at the request belongs to each base station allocates the channel to the mobile station. This effectively allocate the limited channels of various methods have been proposed for, in this case a hybrid channel allocation using genetic algorithms UHGA (Universal Hybrid Channel Assignment using Genetic Algorithm) in rural areas or urban areas, such as universal network applied to a variety of environments that the efficiency is verified through simulation.

• Steel and Composite Structures
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• v.39 no.4
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• pp.471-491
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• 2021

In this study, we estimate the ultimate load of rectangular concrete-filled steel tubes (CFST) by developing a novel hybrid predictive model (ANN-BCMO) which is a combination of balancing composite motion optimization (BCMO) - a very new optimization technique and artificial neural network (ANN). For this aim, an experimental database consisting of 422 datasets is used for the development and validation of the ANN-BCMO model. Variables in the database are related with the geometrical characteristics of the structural members, and the mechanical properties of the constituent materials (steel and concrete). Validation of the hybrid ANN-BCMO model is carried out by applying standard statistical criteria such as root mean square error (RMSE), coefficient of determination (R²), and mean absolute error (MAE). In addition, the selection of appropriate values for parameters of the hybrid ANN-BCMO is conducted and its robustness is evaluated and compared with the conventional ANN techniques. The results reveal that the new hybrid ANN-BCMO model is a promising tool for prediction of the ultimate load of rectangular CFST, and prove the effective role of BCMO as a powerful algorithm in optimizing and improving the capability of the ANN predictor.

• Honam Mathematical Journal
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• v.36 no.1
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• pp.157-165
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• 2014

In this paper, we obtain some common fixed point theorems of single and multivalued maps under hybrid contractive conditions satisfying weakly commuting in IFMS. Our results extend previous ones in IFMS.