• Journal of Ocean Engineering and Technology
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• v.16 no.6
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• pp.25-31
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• 2002

A system identification method is introduced to increase the prediction accuracy of a ship's maneuverability in PMM test, analysis. To improve the accuracy of linear hydrodynamic coefficients, the analysis techniques of pure sway and yaw tests are developed, and confirmed. In the analysis of sway tests, accuracy to linear hydrodynamic coefficients depends on the frequency of sway motion. To obtain nonlinear hydrodynamic coefficients for large drift angles, a combined yaw test is introduced. Using this system identification method, runs of PMM test can be reduced while retaining sufficient accuracy, compared to the Fourier integration method. Through the comparisons with sea trial results and the Fourier integration method, the accuracy and efficiency of the newly proposed system identification method, based on least square method, has been validated.

• The Journal of Korean Academy of Sensory Integration
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• v.7 no.2
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• pp.37-47
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• 2009

Objective : The aim of this study is to verify the effects of group sensory integrative intervention on praxis and socialization for school-aged children with sensory integration disorder. Method : The subjects are five children aged between 7 and 13 with sensory integration disorder. All children had participated in 26 sessions of group sensory integrative intervention. The Bruininks-Oseretasky Test of Motor Proficiency(BOT-2) and The Scale for Basic Socialized Function were used so as to evaluate the praxis and socialization. One group pretest-posttest design was used to verify the effect of group sensory integration(SI) intervention. The statistical difference between before and after the group SI intervention in the BOT-2, Scale for basic socialized function is tested by the Wilcoxon matched-pairs signed ranks test. Results : There is a significant difference in BOT-2(Z=-2.023, p=.043) and Scale for basic socialized function(Z=-2.023, p=.043) scores comparing pre-intervention with post-intervention. Conclusions : The results of this study showed that the group sensory integration intervention is effective in improving the praxis and socialization for school-aged children. However, it is difficult to generalize the conclusion because the number of subjects was limited and the environmental confounding factors had not been considered. Therefore, in the future research, it should supplement the aspect these limitations before applying the sensory integration intervention in order to suggest standard criteria for norm data.

• Journal of ILASS-Korea
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• v.18 no.3
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• pp.132-139
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• 2013

Smoke emissions from light duty diesel vehicles were measured using light extinction method with the free acceleration test mode. The smoke emissions for each measurement cycle of the free acceleration method showed large variations according to driver's pedal pushing pattern. The smoke values for each measurement cycle initially increased and reach a peak value. Integration of the smoke emissions with time for each measurement cycle was performed to get a representative smoke value which was obtained by averaging the integrated results. Two kinds of integration time range were used. One is range over the whole measurement cycle of the free acceleration method. The other is only the acceleration range in the measurement cycle. Overall, variation of the representative smoke values obtained by the integration method was reduced comparing to the traditional representative smoke value which was obtained from a peak smoke value over the measurement cycle. Ten vehicles of the same model with 2.5 liter diesel engines, and seven vehicles of the same model with 2.7 liter diesel engines, were tested using the free acceleration test method.

• Journal of Digital Convergence
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• v.16 no.12
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• pp.647-654
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• 2018

This study was designed to compare the effects of individual sensory integration treatments on the improvement of motor skills and group psychomotorik activities that produce a wide range of interactions with peers. The research targets two 4-year-old children, who are currently in the main building, and 40 minutes of psychomotorik and sensory integration treatment were applied to them twice a week from April 2017 to January 2018. The study method used assessment tools such as B-O test, DeGangi-Berk Test of Sensory Integration (TSI), and MOT4-6 respectively. The results of the study showed that programs in both areas had positive effects on motor skills, with significantly improved performance in balance and postural control, in particular.

• The Journal of Korean Academy of Sensory Integration
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• v.16 no.1
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• pp.25-34
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• 2018

Objective : This study aims to figure out the effect that sensory integration group therapy has on the fine motor, social interaction and playfulness of preschool children with intellectual disability. Methods : Participants were four children from three to five years old who were diagnosed with intellectual disabilities and they participated in twelve sessions of sensory integration group therapy, sixty minutes per session and once a week. Sensory integration group therapy was composed of parallel and peer play-centered gross motor activities, art activities and sensory plays that were related to each theme. Erhardt Developmental Prehension Assessment (EDPA), Penn Interactive Peer Play Scale (PIPPS) and Test of Playfulness (ToP) were used to evaluate participants' fine motor, social interaction and playfulness before and after the intervention. Results of fine motor, social interaction and playfulness before and after the intervention were compared using Wilcoxon matched-pair signed rank test. Results : After sensory integration group therapy intervention, the fine motor skills of participants did not show significant increases, but social interaction and playfulness showed significant increases (p< .05). Conclusion : Although sensory integration group therapy with preschool children with intellectual disability did not show positive improvement in fine motor skills, it showed positive effect on social interaction and playfulness. Group sensory integration therapy might be an intervention approach for all children with disabilities.

• Journal of the Korean Society for Precision Engineering
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• v.13 no.9
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• pp.114-129
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• 1996

This paper describes the whole development phase for the underwater vehicle actuating system with high hydroload torque disturbance. This includes requirement analysis, system modeling, control algorithm design, real time implementation, test and performance evaluations. As for driving control algorithms, fuzzy logic, variable structure and PD(Proportional-Differential) algorithm were designed and implemented on board controller using a single chip microprocessor. Intel 8797. And test and performance evaluation is carried out both single test and wystem integration test. We could confirm the basic performance of actuating system through the single test and gereral developing work of any actuating systems was finished with a single performance test of actuating system without system integration test. But, we suggested that system integration test be needed. System integration test is carried out using G/C HILS(Guidance and Control Hardware-In-the -Loop Simulation) which is constituted flight motion simulator, load simulator, real time host computer and the related subsystems such as inertial navigation system, power supply system and Guidance and Control Computer etc.. The most important practical contribution of this paper is that full system characteristics such as minimal control effort, enhancement of guidance and autopilot performance by the actuating system using G/C HILS technique are investigated. Through full running G/C HILS, in spite of the passing to single tests, some control algorithm resulted in failure as to stability of full system and system time frame.

• Proceedings of the KSR Conference
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• 1999.11a
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• pp.202-208
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• 1999

Train system like high speed train is assemble by a number of subsystem. Therefore, the Integration of train system needs the process that investigates the interface and influence between subsystems. In this paper, It studied the Design & Integration and major process of Korea High Speed Tram Project,

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.129.2-129.2
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• 2010

As a part of the government renewable energy policy, KOWEPO is constructing 300MW IGCC plant in Taean. IGCC plant consists of gasification block, air separation unit and power block, which performance test is separately conducted. Overall performance test for IGCC plant is peformed to comply with ASME PTC 46. Major factors affected on the overall efficiency for IGCC plant are external conditions, each block performance(gasification, ASU, power block), water/steam integration and air integration. Performance parameters of IGCC plant are cold gas efficiency, oxygen consumption, sensible heat recovery of syngas cooler for gasification block and purity of oxygen, flow amount of oxygen and nitrogen, power consumption for air separation unit and steam/water integration among the each block. The gas turbine capacity applied to the IGCC plant is 20 percent higher than NGCC gas turbine due to the low caloric heating value of syngas, therefor it is possible to utilize air integration between gas turbine and air separation unit to improve overall efficiency of the IGCC plant and there is a little impact on the ambient condition. It is very important to optimize the air integration design with consideration to the optimized integration ratio and the reliable operation. Optimized steam/water integration between power block and gasification block can improve overall efficiency of IGCC plant where the optimized heat recovery from gasification block should be considered. Finally, It is possibile to achieve the target efficiency above 42 percent(HHV, Net) for 300MW Taean IGCC plant by optimized design and integration.

• Structural Engineering and Mechanics
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• v.21 no.5
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• pp.539-551
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• 2005

Finite elements based on isoparametric formulation are known to suffer spurious stiffness properties and corresponding stress oscillations, even when care is taken to ensure that completeness and continuity requirements are enforced. This occurs frequently when the physics of the problem requires multiple strain components to be defined. This kind of error, commonly known as locking, can be circumvented by using reduced integration techniques to evaluate the element stiffness matrices instead of the full integration that is mathematically prescribed. However, the reduced integration technique itself can have a further drawback - rank deficiency, which physically implies that spurious energy modes (e.g., hourglass modes) are introduced because of reduced integration. Such instability in an existing stiffness matrix is generally detected by means of an eigenvalue test. In this paper we show that a knowledge of the dimension of the solution space spanned by the column vectors of the strain-displacement matrix can be used to identify the instabilities arising in an element due to reduced/selective integration techniques a priori, without having to complete the element stiffness matrix formulation and then test for zero eigenvalues.

• Journal of Korean Academy of Nursing
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• v.47 no.3
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• pp.431-444
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• 2017

Purpose: This study was conducted to verify the effects of a memory and visual-motor integration program for older adults based on self-efficacy theory. Methods: A non-equivalent control group pretest-posttest design was implemented in this quasi-experimental study. The participants were 62 older adults from senior centers and older adult welfare facilities in D and G city (Experimental group=30, Control group=32). The experimental group took part in a 12-session memory and visual-motor integration program over 6 weeks. Data regarding memory self-efficacy, memory, visual-motor integration, and depression were collected from July to October of 2014 and analyzed with independent t-test and Mann-Whitney U test using PASW Statistics (SPSS) 18.0 to determine the effects of the interventions. Results: Memory self-efficacy (t=2.20, p=.031), memory (Z=-2.92, p=.004), and visual-motor integration (Z=-2.49, p=.013) increased significantly in the experimental group as compared to the control group. However, depression (Z=-0.90, p=.367) did not decrease significantly. Conclusion: This program is effective for increasing memory, visual-motor integration, and memory self-efficacy in older adults. Therefore, it can be used to improve cognition and prevent dementia in older adults.