• 한국정밀공학회지
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• 제23권9호
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• pp.54-60
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• 2006

Fitting process carried out in automobile transmission assembly line is classified into three classes; heat fitting, press fitting, and their combined fitting. Heat fitting is a method that heats gear to a suitable range under the tempering temperature and squeezes it toward the outer diameter of shaft. Its stress depends on the yield strength of gear. Press fitting is a method that generally squeezes gear toward that of shaft at room temperature by press. Another method heats warmly gear and safely squeezes it toward that of shaft. Warm shrink fitting process for automobile transmission part is now gradually increased, but the parts (shaft/gear) assembled by this process produced dimensional changes of gear profile in both radial and circumferential directions. So that it may cause noise and vibration between gears. In order to solve these problems, we need an analysis of warm shrink fitting process, in which design parameters are involved; contact pressure according to fitting interference between outer diameter of shaft and inner diameter of gear, fitting temperature, and profile tolerance of gear. In this study, an closed form equation to predict contact pressure and fitting load was proposed in order to develop optimization technique of warm shrink fitting process and verified its reliability through the experimental results measured in the field and FEM, that is, thermal-structural coupled field analysis. Actual loads measured in the field have a good agreement with the results obtained by theoretical and finite element analysis and also the expanded amounts of the gear profile in both radial and circumferential directions are within the limit tolerances used in the field.

• 한국자동차공학회논문집
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• 제14권1호
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• pp.129-137
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• 2006

This paper studies the effects of the swirl for the variation of intake port configuration that is key parameters in the flow field of direct injection diesel engines. In-cylinder flow characteristics is known to have significant effects on air-fuel mixing, combustion, and emissions. To investigate the effects of the swirl flow, various rpm(250, 500, 750) and two different intake port were used. And to evaluate the swirl motion in the flow field visualization engine, steady state flow test was conducted. Helical port intake port and SCV(Swirl Control Valve) were selected as the design parameters to increase the swirl flow and parametric study was performed. In the case of non-SCV, intake flow rate and non-dimensional swirl ratio were higher than those of SCV for the swirl head type. So, we could strengthen the swirl in the flow field with the swirl head type and don't using SCV. From the results of steady state flow test, non-swirl head type has the most good advantage for intake flow rate, and also the flow rate could be increased by using the SCV slightly. The effects of the type of engine head on intake air flow capability are dominant with respect to the existence of the SCV. We could measure the qualitative grade of swirl by capturing the scattering signal of microballoon from ICCD camera in the visualization diesel engine.

• 전기학회논문지P
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• 제63권4호
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• pp.301-306
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• 2014

Recently in accordance with the rapid development of the industrial society, the accidents caused by dielectric breakdown have been increasing in power grid. It is important to prevent the dielectric breakdown of a high voltage apparatus to reduce the damage from electrical hazards. To establish an electrically reliable database of insulation design criteria for high voltage apparatus, a study on dielectric characteristics test is indispensable. In this study, dielectric characteristics according to field utilization factors (${\xi}$) which are represented as the ratio of mean electric field to maximum electric field are investigated. the dielectric breakdown experiments by using several kinds of electrode systems made with stainless steel are performed by AC breakdown voltage under air-insulation. Also, the experimental results are analyzed by the Weibull distribution. As a result, it is found that the dielectric characteristics of air-insulation are determined by ${\xi}$ as well as arrangement of electrode systems. It is considered that the results of this study would be applicable to designing the air-insulated high voltage apparatuses.

• 한국콘텐츠학회논문지
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• 제13권9호
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• pp.102-110
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• 2013

오늘날 기업에게 기술력과 디자인은 무한경쟁시대에서 요구되는 전제조건으로 인식되고 있다. 대부분의 기업 특히 도자기기업에서는 실용적이거나 또는 제품의 미적인 부분을 개별적으로 다루고 있는 것이 사실이다. 이에 따라 기업의 아이덴티티를 형성하기에 어려움을 겪게 된다. 그러나 독일의 로젠탈사의 경우 이미 1900년대 중반부터 디자인과 더불어 독창적인 프로세스를 통하여 기업의 아이덴티티를 확립하였으며, 독창적인 디자인 매니지먼트를 통해 제품을 생산하는 기업으로 평가되고 있다. 특히 로젠탈의 아이덴티티는 디자인 결과물이 아니라 개발 프로세스를 검증하는 "Jury System"과 독립브랜드 마케팅 그리고 순수 예술가들과의 콜라보내이션과 같은 실험정신에 의해 더욱 독창적으로 형성되고 있다. 특히 디자인 개발에 예술가들이 참여함으로써 이 기업의 도자기 제품은 단순히 생활도자 제품만이 아니라 감상과 수집을 위한 명품으로 평가되고 있다. 또한 로젠탈은 기업 아이덴티티가 단순히 제품에 의해 생성되는 것이 아니라, 디자인 경영기술을 통한 기업 내 외적 요인에 의해 완성될 수 있음을 보여주고 있다.

• 한국의상디자인학회지
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• 제20권4호
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• pp.95-104
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• 2018

This study classified the figurative features of the raglan sleeves presented in the Spring and Summer Collections and Fall and Winter Collections abroad in 2010 and 2018 and analyzed the production methods and patterns of the classified raglan sleeves. The analysis results are described below. The raglan sleeves in the latest fashion trends were classified into Type H, Type A, Type O and Type Y per shape. The production features of raglan sleeves in the latest fashion trends included the cutting lines in various shapes, a flounce that made shoulders look wider, and decorations such as gathers, studs, punching, slits, pleats and tucks. The raglan sleeve design was classified into Yoke Raglan, Armhole Princess Raglan, Semi Raglan, Gathered Raglan, Pleats Raglan, Cowl Raglan, Origami Raglan, Circular Curved Raglan, Capes Raglan and Constructive Design Raglan and the patterns per design were presented. For creative and experimental clothing by the analysis of the features of raglan sleeve structure, a variety of configuration methods need to be developed and implemented. The analysis results of this study will contribute to the development of the fashion industry through small quantity batch production pursuing unique styles as the basis for further study on the configuration methods of raglan sleeves. This study will be used in various ways as education materials on sleeve patterns in the educational field. Through the analysis of sleeve patterns, this study tries to provide basic data for planning the design of raglan sleeves and helping to diversify the ladies' apparel market in the future.

• 한국재난정보학회 논문집
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• 제18권4호
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• pp.706-712
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• 2022

연구목적: 본 연구에서는 우리나라 중부 내륙지역의 연약지반 침하특성을 분석하여 실무에 활용할 수 있도록 하기 위하여 현장실험연구를 실시하였다. 연구방법: 현장실험에서 실측한 10개의 침하계측 자료를 이용하여 설계예측값과 비교분석을 실시하였다. 설계예측값은 Terzaghi의 일차원 압밀침하량분석을 사용하였다. 실험에서 현장계측은 지표침하판을 이용하였다. 연구결과: 예측값과 실제값의 침하거동은 대체로 유사하였으나 침하량 값에서는 실제 침하량 값이 예측 침하량 값에 비하여 30%이하의 침하거동을 보였다. 본 연구지역의 압밀침하율은 9.6%~27.0% 범위를 나타내었으며 평균값은 18.21% 로서 우리나라 중부지역 내륙의 평야지대에 분포된 실트질 연약지반의 침하량 예측은 비교적 매우 과다하게 예측될 수 있는 것으로 분석되었다. 결론: 우리나라 중부지역 내륙의 평야지대에 분포된 실트질 연약지반의 침하량 예측 설계에서는 과다설계 가능성이 있으므로 정밀한 지반조사와 세밀한 예측이 필요한 것으로 판단된다.

• 한국소음진동공학회논문집
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• 제23권10호
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• pp.878-884
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• 2013

The center of gravity and the moment of inertia of railway vehicles are important parameters for running safety and stability in railway vehicle design. However, the exact measurement of those is difficult in manufacturing field. The weight measurement of a railway vehicle beneath the wheel using a weight scale is off by a large amount. This paper suggests a measurement method for the center of gravity and the moment of inertia of railway vehicles using vibration. For the measurement a railway vehicle is suspended using four wires. Direct measurement of the tension of the wires and the period of swinging motion of the suspended railway vehicle with calculations give the exact location of the center of gravity and the moment of inertia in x, y, and z directions, respectively. This implementation was demonstrated using an experimental device and verified numerically.

• 한국전산구조공학회논문집
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• 제19권3호
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• pp.233-238
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• 2006

이 논문에서는 소형 다층 구조물의 진동제어에 적용하기 위한 복합모드의 자기유변유체(MR) 감쇠기를 개발하였다. 우선, 도식적으로 전단, 유동, 복합모드 MR감쇠기의 형태를 설계조건과 함께 표현하였고, 각각의 모드에 대하여 자기장에 따른 감쇠력을 예측하기 위한 해석모델을 유도하였다. 다음으로 적당한 크기의 복합모드 MR감쇠기를 제작하고 자기장에 따른 감쇠특성을 시간영역에서 평가하였다. 마지막으로 지진하중을 받는 소형구조물에 제작된 MR감쇠기가 준능동 제어기로 제어하였을 때의 성능을 수치적으로 평가하였다.

• 대한가정학회지
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• 제43권4호
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• pp.161-172
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• 2005

The present study investigation the effect of a project approach program on children's cognitive styles. It examined closely the characteristics and processes of the project approach program to determine its impact on children's individual cognitive styles such as divergent thinking, field independence, and reflection. The subjects were 384-year-old children. Eighteen children were assigned to the experimental group and twenty to the control group. Pretest-treatment-posttest design was adopted for this study. Collected data were analyzed with SPSS Win 10.0 and processed statistically using average, standard deviation, and ANCOVA. For the children's divergent thinking, the children with the project approach program showed significant difference in fluency and flexibility, but no difference in originality and elaboration, compared to the children in the control group. Children with the project approach program showed more field independence than those in the control group. Children with the project approach program showed no difference in reflection. These results showed that the project approach pro!3ram partly influenced the children's cognitive styles.

• 한국자동차공학회논문집
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• 제9권1호
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• pp.102-111
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• 2001

To describe the air flow characteristics within an air cleaner cover and mass air flow sensor (MAFS) entry region installed in a 3.0L engine air induction system, flow visualization, velocity and turbulence intensity measurements were taken in several view planes. A detailed knowledge of the interaction between the design parameters and the flow structures will enhance our understanding of the motions within the flow field and enable engineers to optimize the induction system and reduce the signal-to-noise ratio in the MAFS output. Emphasis is placed on the analysis of coherent motions and the controlling parameters which affect the air flow in the MAFS entrance region over a flow rate of 13-240 kg/hr. The high speed motion pictures illustrated that the air flow generated within the air cleaner cover under steady state condition is quite complex. In both axial and radial planes of the main passage it was found that the flow pattern is remarkably influenced by the air cleaner cover and main passage configuration. A comparison of the flow patterns and measurements in the original and modified air cleaner cover is presented. Measurements from the MAFS indicated an significant reduction in pressure drop and signal noise for the modified cover as compared with the original cover, over an air flow rate of 13-240 kg/hr.