• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.6 s.249
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• pp.684-690
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• 2006

This study proposes and validates a new column type electric power steering system (EPS-TT). It is driven by a uni-directional motor and two electro-magnetic clutches. The assist motor produces assist torque in only one direction and two clutches transmit the torque to the column of steering system in either left or right direction with respect to the steering input. A full order and a reduced order models are developed to evaluate the EPS-TT. Models are also used to investigate the vehicle responses. A PID control logic is designed to control the torque of the assist motor. A driver model is applied to the system and the resulting performances are analyzed. The results show that the performances of the full order model are similar to those of reduced order model. The results also prove that the performances achieved by the EPS-TT are improved compared to those of a conventional EPS-TT across the frequency domain.

• Computational Structural Engineering
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• v.8 no.3
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• pp.123-133
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• 1995

This study presents an application of object-oriented methodology for structural design process. A prototype of integrated structural design system is developed by introducing a structural analysis object model(SAOM) and structural design object model (SDOM). This SAOM module, which models structural member, performs structural analysis using FEM approach and the SDOM module checks structural members based on Korea steel design standard. The abstraction, encapsulation and reusability properties of the proposed models are in establishing the integrated structural design system.

• Transactions of Materials Processing
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• v.4 no.1
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• pp.9-16
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• 1995

Model material technique, which requires only the small space of experimental set-up and low cost for experiment, is used to estimate the deformed profile and the forging load in rotary forging. The materials and working conditions are determined to satisfy the similitude conditions between the model test and the prototype test. The model material of the so-called plasticine and the mild steel are chosen as specimens, and they represent almost the same value of strain gardening exponent in the stress-strain relationship. Lubricant in the model test is also carefully selected so that it gives the same frictional conditions at the tool-specimen interface. Experiments for two kinds of specimens are carried out in each testing equipment at room temperatue. From the experiments the deformed dimensions and the forging loads are measured and compared with each other by using the simulation coefficients. It is shown that there are good agreements between the model test and the prototype test. Finally, for verifying the availability of the model material technique this mathod is applied to forging of bevel gear product. the good result is obained which can demonstrate that the model material technique is very efficent for estimating or developing a new process.

• Journal of Korean Society of Steel Construction
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• v.10 no.3 s.36
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• pp.369-381
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• 1998

This paper is intended to show some new approaches and concepts for the development of system model and prototype software for computer-aided Monitoring and Assessment(M&A) of grand bridges. The system model that incorporates optimal strategies for M&A of grand bridges is suggested. Reliability models are developed and a reliability-based capacity rating method is established for the evaluation of the bridge safety and reliability based on the real responses measured from a series of field load tests. Based on the proposed models, an integrated prototype software is then developed for computer-aided M&A of grand bridges under the environment of the graphic user interface, which is successfully applied to the M&A of an existing cable-stayed bridge. It may be stated that the system model and prototype software developed in this paper can be utilized and implemented in the development of the computer-aided M&A system for cable-stayed and suspension bridges.

• Journal of the Korea Concrete Institute
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• v.22 no.6
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• pp.805-816
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• 2010

For earthquake simulation test it is essential to make sure the similitude in behaviors between the full scale prototype and the reduced scale model. This paper presents the test results obtained through the cyclic lateral-force test, on two-story RC wall subassemblages. A lower 2-story portion of the prototype structure was selected as subassemblages. The global behavior such as the strength and ductility, and the local behavior such as flexural, shear and uplift deformation were measured. The test results of the 3 : 5 scale specimens representing the prototype were compared with those of 1 : 7 scale models. Two types of subassemblages were used: One with lintel beams and one without lintel beams. The comparison shows that 1 : 7 scale model simulated in general successfully the global and local behaviors of the prototype.

• Korean Journal of Acupuncture
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• v.39 no.3
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• pp.71-83
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• 2022

Objectives : Instructional design is the systematic approach to the Analysis, Design, Development, Implementation, and Evaluation of learning materials and activities. We aimed to apply the rapid prototyping to instructional systems design (RPISD) in meridianology laboratory, a subject in which students train acupuncture to develop lesson plan. Methods : The needs of the stakeholders including client, subject matter expert and students were analyzed using the performance needs analysis model. Task analysis was implemented by observation and interview. First prototype was drafted and implemented in meridianology laboratory class once. The second prototype was modified from the first, by usability evaluation of the stakeholders. Results : The client requested an electronically documented manual to improve the quality of acupuncture training. The learner requested an extension of practice time and detailed practice guidelines. The main problems of students' performance were some cases of violation of clean needle technique, the lack of communication between the operator and recipient in direct, and lack of confidence in their own performance. Stakeholders were generally satisfied with the proposed first prototype. Second prototype of lesson plan was produced by modifying some contents. Conclusions : A lesson plan was developed by applying the systematic RPISD model. It is expected that the developed instructional design may contribute to the quality improvement of meridianology laboratory education.

• Journal of Korean Society of Transportation
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• v.19 no.6
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• pp.143-160
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• 2001

Micro-simulation models have been recognized as an efficient assessment tool in developing traffic signal control technologies. In this paper a prototype of a microscopic simulation model which can be applied to evaluate the performance of traffic-adaptive signal control strategies was developed. In the simulation process, space-based arrays were appled to estimate parameters of car following and lane changing models. Two levels of link types, a micro-type and macro-type links, were also embodied in the simulation process. The proposed model was tested on a test network consists of 9 intersections. The performance of the proposed model was evaluated in link by link comparisons with the results of NETSIM. The results show that the proposed model could appropriately simulate traffic flows of the test network. The model also produces traffic adaptive signal timings, cycle lengths and green times for turning movements, based on the detector data. It implies that the optimization process of the model produces reasonable signal timings for the test network on the cycle basis.

• Wind and Structures
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• v.19 no.3
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• pp.233-247
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• 2014

Vortex-induced oscillation is a type of aeroelastic phenomenon, to which extended structures such as long-span bridges are most susceptible. The vortex-induced vibration (VIV) behaviors of a concerned bridge were investigated conventionally in virtue of wind tunnel tests on string-mounted sectional models. This necessitates the building of a linkage between the response of the sectional model and that of the prototype structure. Although many released literatures have related to this issue and provided suggestions, there is a lack of consistency among them. In this study, some theoretical models describing the vortex-induced structural motion, including the linear empirical model, the nonlinear empirical model and the modified (or generalized) nonlinear empirical model, are firstly reviewed. Then, the concept of equivalent mass density is introduced based on the principle that an equal input of energy should result in identical structural amplitudes. Based on these, the theoretical linkages between the amplitude of a section model and that corresponding to the prototype bridge are discussed with different analytical models. Theoretical derivation indicates that such connections are dependent mainly on two factors, one is the presupposed shape of deformation, and the other is the theoretical VIV model employed. The theoretical analysis in this study shows that, in comparison to the nonlinear empirical models, the linear one can result in obvious larger estimations of the full bridges' responses, especially in cases of cable-stayed bridges.

• Hwankyungkyoyuk
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• v.19 no.3
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• pp.150-164
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• 2006

This study reviewed a recently developed environmental education model 'ENVISION' and analyzed the value of the ENVISION program with environmental education(EE) perspective. Also this study proposed a prototype model of a inquiry-based water environmental education model with watershed concepts as a result of discussion of tills research. In the review of ENVISION, this research followed the theoretical framework of 'Inquiry-Based EE' that was previously proposed by the author. The ENVISION was characterized in tills research as two directions: watershed and scientific inquiry. Tills research argued that the watershed concept has a potentially very good meaning in EE because watershed enables 'holistic' view in EE area, and that the scientific inquiry in ENVISION seeks evidence-based explanation about local watershed environmental problems. That belongs to the scientific inquiry, which is also 'Inquiry-Based EE' and has internal value under EE perspective. Finally, this research proposed a prototype EE model that is about watershed concept, and is based on inquiry as general sense (scientific and insightful inquiries) and 'Environmental Studies for EE, (ESEE)' as the inquiry directions. The proposed model can be said a combination of the watershed concept and inquiry-based EE, and it seems that the model materializes better the EE nature than the ENVISION model.

• Journal of the Korea Computer Industry Society
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• v.2 no.2
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• pp.151-156
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• 2001

We describe a new representation for learning concepts that differs from the traditional decision tree and rule induction algorithms. Our algorithm PROLEARN learns one or more prototype per class and follows instance based classification with them. Prototype here differs from psychological term in that we can have more than one prototype per concept and also differs from other instance based algorithms since the prototype is a "ficticious ideal example". We show that PROLEARN is as good as the traditional machine learning algorithms but much move stable than them in an environment that has noise or changing training set, what we call 'stability’.tability’.