• Journal of Korean Society of Steel Construction
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• v.14 no.5 s.60
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• pp.675-682
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• 2002

The beam of composite structure composed of the RC structure in the end part and steel structure in the central palt were investigated during cyclic loading, in order to evaluate strength, stiffness, and deformational capacity. The parameters used in this study include the amount of reinforced steel bar between the steel beam and RC structure and the existence of the sticking plate. Test results showed that all specimens had stabilized hysteresis loops. Likewise, the specimens with sticking plate had higher load-carrying capacity compared with the one without it. In addition, the stiffness of the composite structure was higher than the steel structure. All specimens also showed good rotational capacity.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.6
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• pp.771-780
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• 2010

This paper describes the design process of a six-component force/torque (F/T) sensor. The new six-component F/T sensor having leaf spring ends has been developed using a cross beam structure as the basic sensing element. Fundamental strain analysis of both ends fixed beam having a leaf spring structure is performed by finite element analysis. In order to obtain similar output sensing strains from the six component loads and minimize coupling strains, the optimal location of strain gages is determined and the strain gages are connected so that the bridge circuits with four strain gages would be balanced. Using leaf spring ends instead of rigid fixed ends, remarkable increment in output sensing strain can be achieved for two component forces. Several modifications in design result in a similar sensing strain of approximately $400\;{\mu}m/m$ for the six-component forces and moments, and a reduced coupling strain of $0\;{\mu}m/m$ between the forces and moments.

• Economic and Environmental Geology
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• v.37 no.5
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• pp.437-457
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• 2004

The geology of the Kualakulun in the Middle Kalimantan, Indonesia comprises Permian to Carboniferous Pinoh Metamorphic Rocks and Cretaceous Sepauk Plutonics of the Sunda Shield, late Eocene Tanjung Formation, Oligocene Malasan Volcanics, Oligocene to early Miocene Sintang Intrusives and Quaternary alluvium. Tanjung Formation was deposited in low-and high-sinuosity channel networks developed on the proximal to distal delta plain and delta front forming southward paleoflow system, which, in turn, gradually change into shallow marine environment. Four main deformational phases are recognized: D1, folding of metamorphic rocks accompanied by development of S1 schistosity under regional metamorphic condition; D2, ductile shearing in Cretaceous granitoids; D3, folding of metamorphic rocks accompanied by S2 crenulation cleavage; D4, faulting under N-S compressional regime during Tertiary times, producing NE-trending sinistral and NW-trending dextral strike-slip faults and N-S to NNE-trending normal faults.

• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.259-259
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• 2019

시계열 자료들을 분석하고자 하는 경우 자료가 정상성(stationarity)을 만족하는 경우는 드물다. 특히 계절성을 제거한 자료들에서는 정량화하기 어려운 주기성이 많이 관찰된다. 즉, 어떤 특정지역에서 나타나는 현상이 다른 기상 현상에 영향을 미칠 것은 자명한 일이나 그 관련성이 선형(linearity)일 가능성은 극히 드물다. 따라서 그들 사이의 관련성이 선형성에 근거한 지표들로 정량화되어야 한다. 이러한 문제점을 해결하기 위해서 다양한 방법이 사용되며 그중에서 웨이블릿 분석을 통해 본 연구를 진행하였다. 웨이블릿 변환(wavelet transforms)은 특수한 함수의 집합으로 구성되어 기존 웨이블릿 신호의 분석을 위해 사용되는 방법이다. 이 변환은 푸리에 변환에서 변형된 방법으로 특정한 기저 함수(base function)를 이용하여 기존의 시계열 자료를 주파수로 바꾸는 변환이다. 웨이블릿 변환에서 기저 함수를 모 웨이블릿이라고 하며 이를 천이, 확대 및 축소 과정을 통해 주파수를 구성한다. 웨이블릿 분석은 모 웨이블릿을 분해하고 재결합하여 시계열 분석을 할 수 있다. 모 웨이블릿 함수에는 Haar, Daubechies, Coiflets, Symlets, Morlet, Mexican Hat, Meyer 등의 여러 가지 종류의 모 웨이블릿 함수가 있으며 모 웨이블릿이 달라지면 결과가 다르게 나타난다. 기존에는 Morlet 웨이블릿을 주로 이용하여 주파수분석에 사용하여 결과를 도출하였다. 그리고 시계열 자료는 크게 백색잡음(White Noise), 장기기억(Long Term Memory), 단기기억(Short Term Memory)으로 나뉜다. 각 시계열 자료의 종류에 따라 임의의 시계열 자료를 산정하여 그에 따른 웨이블릿 분석을 통해 모 웨이블릿의 특성을 도출하였다. 본 연구에서는 웨이블릿 분석을 통해 시계열 자료의 최적 모 웨이블릿을 결정하고자 남방진동지수(SOI), 북극진동지수(AOI)의 자료를 이용하여 웨이블릿 분석을 시도하였다. 웨이블릿 분석은 모 웨이블릿에 따라 달라지는 결과를 토대로 분석하였으며 이를 정상성과 지속성에 따라 분류된 시계열에 적용하여 최적 모 웨이블릿을 결정하고자 하였다. 본 연구에서는 임의의 시계열 자료에서 설정한 최적의 모 웨이블릿을 AOI와 SOI와 같은 실제 시계열 자료에 대입하여 분석을 진행하였다. 본 연구에서는 시계열 자료의 종류를 구분하고 자료의 특성에 따라 가장 적합한 모 웨이블릿을 구하고자 하였다.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.35 no.5
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• pp.277-286
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• 2022

The elastic and inelastic responses obtained from the experimental and analytical results of two RC building structures under the service level earthquake (SLE) and maximum considered earthquake (MCE) in Korea were used to weinvestigate the characteristics of the mechanisms resisting shear and torsional behavior in torsionally unbalanced structures. Equations representing the interactive effect of translational drift and torsional deformation on the shear force and torsional moment were proposed. Because there is no correlation in the behavior between elastic and inelastic forces and strains, the incremental shear forces and incremental torsional moments were analyzed in terms of their corresponding incremental drifts and incremental torsional deformations with respect to the yield, unloading, and reloading phases around the maximum edge-frame drift. In the elastic combination of the two dominant modes, the translational drift mainly contributes to the shear force, whereas the torsional deformation contributes significantly to the overall torsional moment. However, this phenomenon is mostly altered in the inelastic response such that the incremental translational drift contributes to both the incremental shear forces and incremental torsional moments. In addition, the given equation is used to account for all phenomena, such as the reduction in torsional eccentricity, degradation of torsional stiffness, and apparent energy generation in an inelastic response.

• Journal of Korean Society of Forest Science
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• v.87 no.1
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• pp.40-49
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• 1998

This study aimed to provide a strategy for selecting an adequate combination of growth intervals(i.e. times between age $T_1$ and age $T_2$) to be used to improve the reality of the growth equation through obtaining better precision of parameter estimates. Variety of growth functions were fitted to the data and one equation which best fitted the data was chosen for the analysis. A modified Schumacher projection equation, selected as a best equation, that included dummy variables representing locality as a predictor variable was fitted for basal area and height equations with nonoverlapping growth interval and all possible growth interval data sets of Douglas-fir(Pseudotsuga menziesii Mirb.Franco). The data were measured in all parts of the South Island of New Zealand. It was found that the precision of parameter estimates was increased in both basal area and height equations by using data set which contained a range of measurement intervals from short to long term.

• Food Science and Preservation
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• v.22 no.6
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• pp.901-907
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• 2015

Genetically modified (GM) pepper H15 containing the gene for cucumber mosaic virus (CMV) coat protein (CP) and its control line non-GM pepper P2377 were investigated for their allergic risk. Amino acid sequence of the inserted gene product CMV-CP was compared with those of known allergens. No known allergen had greater than 35% amino acid sequence homology over an 80 amino acid window or more than 8 consecutive identical amino acids. Protein patterns of GM and non-GM pepper extracts were evaluated by SDS-PAGE, which showed similar distribution of protein bands for both GM and non-GM pepper. Antigen-antibody reactions were compared between GM and its non-transgenic parental control. ELISA and immunoblot analysis of sera from allergic patients showed some IgE reactivity; however, no differences were observed between GM pepper H15 and P2377. We therefore conclude that CMV-CP is less likely to be an allergen; the protein composition and allergenicity of the GM pepper H15 is not different from that of P2377 and safe as a commercial host.

• Korean journal of applied entomology
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• v.53 no.3
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• pp.199-207
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• 2014

It is true that the proper environmental risk assessments for many GM (Genetically Modified) insects almost have not been executed in Korea. Therefore, we tested the environmental risk assessment about GM silkworms if there is any difference between GM silkworms and non-GM silkworms by the following three measurements. First, we measured their mobility in the breeding environment conditions with food and without food. Secondly, we measured their viability at the artificial extreme environmental conditions (low and high temperature and humidity, absent/present of foods,) after escaping from their breeding environments. Thirdly, we observed the number of laying eggs and their hatchability between GM silkworms and non-GM silkworms with four different pair experiments. The mobility of GM silkworms and non-GM silkworms statistically did not differ, and the egg productivity and hatchability were not also different. The hatchability by couple of GM female silkworms and non-GM male silkworms was lower than by non-GM male and female couple between the GM silkworms and non-GM silkworms, and there was statistically different. Relatively, the viability of GM silkworms was lower than non-GM silkworms. We could not exactly test for viability of silkworms in low temperature conditions because of their hibernating. Although there was any difference in viability and hatchability between GM silkworms and non-GM silkworms, all ability of GM silkworms was lower than non-GM silkworms. Conclusively, the environmental risk of GM silkworm was relatively lower than non-GM silkworm in this study.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.143-143
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• 1993

현재 시판되고 있는 정장용 생균 제제에 함유되어있는 정장 균주의 하나인 Bifidobacterium bifidum은 항결핵제 중 rifampicin에 감수성으로 rifampicin과 병용 투여시 본래의 정장 효과를 기대할 수없다. 따라서, rifampicin에 내성인 돌연변이 균주를 얻기 위해 B. bifidum을 N-methyl-N'-nitro-N-nitrosoguanidine(MNNG)로 처리하여 rifampicin에 내성인 30 종의 균주를 선별하였고, rifampicin에 대한 Minimal Inhibitory Concentration (MIC)를 측정해 본 결과 내성이 1,000 배 이상 상승하였다. 균주 동정을 위하여 fructose-6-phosphate phosphoketolase test를 실시해 본 결과 Bifidobacterium임이 확인되었다. 이들 내성 균주들의 유기산 생산량을 측정하여 그 생산량이 모균주와 가장 유사한 3 종의 균주를 선발하였다. 이들에 대하여 Escherichia coli 생육 억제능을 시험해 본 결과 E. coil 생육 억제능이 모균주와 유사하였다. 또, rifampicin을 함유한 배지에서 돌연변이 균주를 배양시킨 경우 rifampicin이 안정한 상태로 잔존한 것을 알 수 있었다. 이것으로 보아 돌연변이 균주들은 rifampicin을 분해 또는 변형시키는 효소를 생산하지 않는다고 볼 수 있다. 이상의 결과로 본 연구에서 개발한 돌연변이 균주들, 즉 B. bifidum RFRll, RFR21 그리고 RFR61은 rifampicin에 내성이면서 모균주와 동일한 생화학적 특성을 갖는 정장 균주로 여겨진다.

• Journal of the Korean Institute of Gas
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• v.17 no.5
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• pp.37-41
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• 2013

This paper presents the strength safety of stress and deformation behaviors using the finite element method as a function of the thickness of the protective helmets with and without an extruder on the top of the shell structure. The helmet that would provide head and neck protections without causing discomfort to the user when it was worn for long periods of time should be manufactured for increasing the safety and impact energy absorption. The stress analyzed results show that when the impulsive force of 4,540N is applied on the top surface of a helmet, the safe thickness is 3.7mm for the conventional helmet and 3.2mm for the modified new helmet. Based on the deformation analysis, the FEM results recommend that the safe thickness is 3.2mm for the conventional helmet and 2.0mm for the modified new helmet. Thus, it may be more safe design of the helmet, which has an extruded structure on the summit surface of the helmet.