• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 춘계학술대회 논문집
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• pp.700-705
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• 2003

The object of this study is to ensure the stability of flat freight cars using vibration performance test and static load test of body structures. We examined the flat car though static load test and dynamic characteristics analysis related traveling stability and vibration performance. In the results of static load test of body structures for flat car, all structures satisfied allowable stress of materials. The vibration performance test was satisfied with allowable standards. Although flat car exceed speed a little at some speed interval, it was estimated that the cause was not cars but rail.

• 제어로봇시스템학회논문지
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• 제6권1호
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• pp.51-56
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• 2000

This paper presents the characteristics of the dynamic response and calibration technique on a linear variable differential transformer(LVDT). The linear error of the LVDT was proven $\pm$1% in the static calibration and $\pm$0.5% in the dynamic calibration. In this paper, the linearity error generated in the static and dynamic state of the core movement can be eliminated using the correction algorithem of the static and dynamic state derived from the least square linear approximation for the nonlinearity of the curves of direct data fitting and Lagrange polynomials. With the static and dynamic calibration method, the calibration accuracy of the LVDT can be reduced to within $\pm{0.5%.}$.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2007년도 하계종합학술대회 논문집
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• pp.295-296
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• 2007

Fake fingersubmission to the sensor is a major problem in fingerprint recognition systems. In this paper, we introduce a novel liveness detection method using multi-static features. For convenience and usefulness of field application, static features are only considered to detect 'live' and 'fake' fingerprint images. Individual pore spacing, noise of image and first order statistics of image are analyzed as our static features to reflect the Physiological and statistical characteristics of live and fake fingerprint.

• 한국철도학회논문집
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• 제7권1호
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• pp.49-54
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• 2004

Particularly derailing freight wagon, which are loaded with dangerous chemicals, has large damages on humans and environment. In this paper the dynamic characteristic of the laminated leaf spring under extreme situation, for example derailment, is examined. The leaf spring has a static hysteresis. Not only the friction value, but also the spring rate are influenced by this hysteresis characteristic. Because of the static hysteresis of the leaf spring the spring rate must be used in normal operation depending upon the loading and the kind of the excitation with the up to 10-fold value of the static spring rate. Some characteristics of the leaf spring can be treated like well-known viscous damping, but fer special situation (preload and/or excitation) particular calculation are necessary.

• 한국지진공학회논문집
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• 제22권1호
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• pp.15-22
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• 2018

Pseudo-static approach has been conventionally applied for the design of gravity type quay walls. In this method, seismic coefficient ($k_h$), expressed in terms of acceleration due to gravity, is used to convert the real dynamic behavior to an equivalent pseudo-static inertial force for seismic analysis and design. Therefore, the calculation of an appropriate $k_h$ considering frequency characteristics of input earthquake is critical for representing the real dynamic behavior. However, the definitions of $k_h$, which is used for simplified analysis in Korea, focuses only on convenience that is easy to use, and the frequency characteristics of input earthquake are not reflected in the $k_h$ definitions. This paper evaluates the influences of the frequency characteristics of input earthquake on $k_h$ by initially reviewing the $k_h$ definitions in the existing codes of Japan for port structures and then by performing a series of dynamic centrifuge tests on caisson gravity quay walls of different earthquake input motions (Ofunato, Hachinohe). A review of the existing codes and guidelines has shown that the $k_h$ values are differently estimated according to the frequency characteristics of input earthquake. On the other hand, based on the centrifuge tests, it was found that the permanent displacements of wall are more induced when long-period-dominant earthquake is applied.

• 한국전기전자재료학회논문지
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• 제18권1호
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• pp.6-11
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• 2005

In this paper, two types of vertical SIT(Static Induction Transistor) structures are proposed to improve their electrical characteristics including the blocking voltage. Besides, the two dimensional numerical simulations were carried out using ISE-TCAD to verify the validity of the device and examine the electrical characteristics. First, a trench gate region oxide power SIT device is proposed to improve forward blocking characteristics. Second, a trench gate-source region power SIT device is proposed to obtain more higher forward blocking voltage and forward blocking characteristics at the same size. The two proposed devices have superior electrical characteristics when compared to conventional device. In the proposed trench gate oxide power SIT, the forward blocking voltage is considerably improved by using the vertical trench oxide and the forward blocking voltage is 1.5 times better than that of the conventional vertical power SIT. In the proposed trench gate-source oxide power SIT, it has considerable improvement in forward blocking characteristics which shows 1500V forward blocking voltage at -10V of the gate voltage. Consequently, the proposed trench oxide power SIT has the superior stability and electrical characteristics than the conventional power SIT.

• 한국융합학회논문지
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• 제12권2호
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• pp.317-326
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• 2021

본 연구는 댄스스포츠 참여 부부의 성격특성에 따른 부부친밀감의 자기 및 상대효과를 규명하는데 목적이 있으며 댄스스포츠에 참여하고 있는 부부 148쌍을 대상으로 자료를 수집하였다. 연구문제를 해결하기 위해 SPSS 25.0과 AMOS 25.0을 이용하여 APIM모형을 분석을 실시한 후 다음과 같은 결론을 얻었다. 첫째, 신경증과 관련하여 남편과 아내 모두 유의한 차이가 나타났으며, 남편의 부부친밀감에 대한 아내의 신경증은 부적 영향을 받았고 아내는 상대적으로 낮은 정적인 영향을 받는 것으로 나타났다. 둘째, 개방성과 관련하여 남편에게만 유의한 차이가 나타났으며, 남편의 부부친밀감에 대한 아내의 개방성은 상대적으로 부적 영향을 받는 것으로 나타났고 아내는 동일 수준의 정적인 영향을 받는 것으로 나타났다. 셋째, 외향성과 관련하여 아내에게만 유의한 차이가 나타났으며, 아내가 상대적으로 낮은 정적인 영향을 받는 것으로 나타났다. 넷째, 성실성과 관련하여 남편과 아내 유의한 차이가 나타나지 않았으며 서로 정적인 영향을 미치는 것으로 나타났다. 다섯째, 친화성과 관련하여 아내에게만 유의한 차이가 나타났으며, 아내가 상대적으로 낮은 정적인 영향을 받는 것으로 나타났다. 이를 통해 부부는 바람직한 여가활동을 선용하고 긍정적인 부부여가문화를 형성하여야 할 것이다.

• 한국식품과학회지
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• 제35권6호
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• pp.1150-1154
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• 2003

식초공장에서 Acetobacter pasteruianus로 정치배양중인 식초 생산과정과 숙성중인 현미식초를 오염시켜 균막을 형성한 것으로부터 균을 분리하여 식초를 오염시키는 균의 특성을 밝히고자 하였다. 공장에서 식초제품을 생산하거나 가정에서 식초제품을 사용할 경우에 오염을 일으키는 초산균의 생육에 관하여 배양조건 및 생육억제 방법을 검토하였다. 초산균에 오염되어 균막이 형성된 식초로부터 초산균을 분리하여 형태학적, 배양적 및 생리학적 특성을 검토한 결과 Acetobacter속에 포함됨을 알 수 있었다. 그리고 정치배양 기간 동안에 셀룰로오스 생산량을 확인하고자 14일간 배양한 결과 두꺼운 셀룰로오스를 생성하여 Acetobacter xylinum으로 판단되었으며 7%이상의 초산농도와 10%의 에탄올농도, 1.5%의 NaCl농도, $10^{\circ}C$ 이하와 $40^{\circ}C$ 이상의 온도에서 생육할 수 없었다.

• 한국자동차공학회논문집
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• 제23권3호
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• pp.344-351
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• 2015

Braking force inspection of vehicles in service is certainly one of the most important characteristics that affect vehicle safety. Up to now, in domestic country, the regular safety inspection of vehicles in service has been tested with a roller type brake test (a static braking force inspection system). But, in EU and USA etc. in recent years, it has been tested with a plate type brake test (a dynamic braking force inspection system). In this study, to compare the characteristics of above two test systems, the correlations for the results of braking force are evaluated statistically. As the results, in the case of main braking force, the range of the $R^2$ of the deviation for the left and right side is 0.5386 ~ 0.6231 in the rear axle and 0.0032 ~ 0.0052 in the front axle respectively, then the $R^2$ in the front axle is lower than that in the rear axle and the total variation is unexplained by the least-squares regression line statistically. Also, the p-value for the deviation of the left and right in the front axle is 0.4839 ~ 0.5755, then it has nonsignificant in the front axle. Therefore, the static braking force inspection system can not reflect the inertia force that there is a load transfer from the rear axle to the front axle during braking. Accordingly, it is necessary to adopt the dynamic braking force inspection system which can reflect the inertia force on the regular vehicle safety inspection in domestic country.

• 한국농공학회논문집
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• 제65권5호
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• pp.1-11
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• 2023

Due to climate change and aging of reservoirs, damage to embankment slopes is increasing. However, the safety diagnosis of the reservoir slope is mainly conducted by visual observation, and the time and economic cost are formidable to apply soil mechanical tests and slope stability analysis. Accordingly, this study presented a predicting method for the compaction and strength characteristics of the reservoir embankment soil using a portable static cone penetration test. The predicted items consisted of dry density, cohesion, and internal friction angle, which are the main factors of slope stability analysis. Portable static cone penetration tests were performed at 19 reservoir sites, and prediction equations were constructed from the correlation between penetration resistance data and test results of soil samples. The predicted dry density and strength parameters showed a correlation with test results between R² 0.40 and 0.93, and it was found to replace the test results well when used as input data for slope stability analysis (R² 0.8134 or more, RMSE 0.0320 or less). In addition, the prediction equations for the minimum safety factor of the slope were presented using the penetration resistance and gradient. As a result of comparing the predicted safety factor with the analysis results, R² 0.5125, RMSE 0.0382 in coarse-grained soil, R² 0.4182 and RMSE 0.0628 in fine-grained soil. The results of this study can be used as a way to improve the existing slope safety diagnosis method, and are expected to be used to predict the characteristics of various soils and inspect slopes.