• 한국강구조학회 논문집
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• 제18권2호
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• pp.123-135
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• 2006

이 연구에서는 원형기둥-상자형보 접합부의 다이아프램 형상에 따른 거동특성과 다이아프램 설계방법에 관한 것이다. 강재 원형기둥-상자형보 접합부의 다이아프램은 상자형보 하부플랜지로부터 전달되는 집중력을 지지하게 되며, 보와 기둥의 강도 뿐만아니라 접합부의 거동에 큰 영향을 미치게 된다. 기존의 연구에서는 부정정 곡선보 모델로부터 유도된 다이아프램의 응력계산식이 제시되어 있으나, 설계식으로 활용되기에는 계산과정이 난해하고 유도과정이 비합리적이다. 또한 접합부 강도에 대한 다이 아프램의 역할을 고려하지 않음으로써 다이아프램의 합리적인 설계가 이루어 지지 못하고 있다. 따라서 이 연구에서는 접합부 다이아프램의 설계변수에 대한 비선형 유한요소 해석을 수행하여, 다이아프램의 형상에 따른 강도특성을 검토하였다. 또한 원형기둥-상자형보, 접합부 다이아프램의 이론식이 접합부의 실제 거동과 큰 차이를 나타냄을 확인하였고, 보와 기둥 및 다이아프램 강성을 고려한 강재 원형기둥 접합부 다이아프램의 설계방법을 제안하였다.

• The Journal of Korean Physical Therapy
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• 제15권1호
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• pp.38-60
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• 2003

The purpose of this study was to observe the effects of Far-infrared on mice rheumatoid arthritis induced by type II collagen. The author peformed several experimental tests which were the hematoxylin-eosin tissue stain, the hind paw thickness, and ELSIA of cytokines(TNF-$\alpha$, IL-1$\beta$). On day 14 and 21, FIR-Tx. group decreased in synovial membrane thickness more than control II group FIR-Tx group decreased in hind paw thickness more than control II group. In the ELISA test of TNF-$\alpha$ concentration, control II group significantly increased in the concentration more than normal and FIR-Tx. group on day 7, 14, and 21. In the ELISA test of IL-$\beta$ concentration, FIR-Tx. group decreased in the concentration more than control II group on day 14 and 21. With J's Linear Function Data Process Program, researchers can get the estimated the concentration or the hind paw thickness from this experiment. The estimated results would be a good guide to therapists and researchers, planning Far-infrared application on the rheumatoid arthritis. These results indicated that far-infrared irradiating appeared to reduce the concentration of TNF-$\alpha$ and IL-1$\beta$ at mouse model of autoimmune arthritis. It would be considered that Far-infrared has an effect on relieving rheumatoid arthritis.

• 토지주택연구
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• 제8권3호
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• pp.113-121
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• 2017

Wirye New Town is constructed as a new complex city with three municipalities. Infrastructure must be managed by administrative districts, but integrated management is also needed when considering the planned identity and efficient management and operation aspects of a new town. The purpose of this study is to establish why the integrated management of infrastructure is needed, to form a consensus of stakeholders and to set priorities of integrated management considering characteristics of each facility. This thesis analyzes the order of priorities for integrated management of the infrastructures in Wirye New Town. The study includes an analytic hierarchy process (AHP) survey that asked 95 local city officials and experts in city planning about important values to consider, such as efficiency, equity, and identity, for the integrated management of infrastructures in Wirye New Town. Another survey requested these same people to identify the priorities for integrated management in terms of different infrastructure types. The results are as follows. Those who were surveyed considered efficiency(0.442) to be the most important value for integrated management. Equity was deemed to be the next most important(0.369), followed by identity(0.190). The second step in the AHP survey revealed that "efficiency of management governance" (0.202) was considered to be the most important, then "equity of infrastructure quality among the sub-regions" (0.155), and finally "efficiency for improvement of quality and quantity of services" (0.133). The results of the survey about the priority for integrated management among infrastructure types and AHP shows that 'specialized facilities', 'Space facilities located in more than two municipalities', and 'linear facilities located in more than two municipalities.' are important.

• 한국재료학회지
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• 제15권7호
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• pp.439-443
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• 2005

The oxidation behavior and the thermal stability of nanocrystalline Al-25Ti-8Mn intermetallic compound were investigated. $Al_3Ti$ intermetallic compound, which has a potential for high temperature structural material, was fabricated by mechanical alloying(MA) with $8at.\%$ Mn to enhance the thermal stability and ductility. And Al-25Ti-8Mn intermetallic compound was sintered by spark plasma sintering(SPS) at $700^{\circ}C$. After sintering process, cubic $Ll_2$ structure was maintained without phase transformation and the grain size was about 50nm. To investigate the oxidation behavior of the specimens, thermal gravimetric analysis(TGA) was performed at 700, 800, 900, and $1000^{\circ}C$ for 24 h in $O_2$. As the temperature increased from $700^{\circ}C\;to\;900^{\circ}C$ the weight gain of specimens increased. However at $1000^{\circ}C$, unlike the oxidation behavior of $700^{\circ}C\;to\;900^{\circ}C$, the weight gain of specimen decreased drastically and the transition from linear rate region to parabolic rate region occurred rapidly due to the dense $\alpha-Al_2O_3$.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2013년도 추계학술대회 논문집
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• pp.291-291
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• 2013

The interior vehicle noise due to the exterior aerodynamic field is an important topic in the acoustic design of a car. The air flow detached from the A-pillar and impacting the side windows are of particular interest as they are located close to the driver / passenger and provides a lower insulation index than the trimmed car body parts. HMC is interested in the numerical prediction of this aerodynamic noise generated by the car windows with the final objective of improving the products design and reducing this noise. The methodology proposed in this paper relies on two steps: the first step involves the computation of the exterior flow and turbulence induced non-linear acoustic field using the CAA(Computational aeroacoustics) solver CAA++. The second step consists in the computation of the vibro-acoustic transmission through the side window using the finite element vibro-acoustic solver Actran. The internal air cavity including trim component are included in the simulation. In order to validate the numerical process, an experimental set-up has been created based on a generic car shape. The car body includes the windshield and two side windows. The body is made of aluminum and trimmed with porous layers. First, this paper describes the method including the CAA and the vibro-acoustic models, from the boundary conditions to the different components involved, like the windows, the trims and the car cavity is detailed. In a second step, the experimental set-up is described. In the last part, the vibration of the windshield and windows, the total wind noise level results and the relative contributions of the different windows are then presented and compared to measurements. The influence of the flow yaw angle (different wind orientation) is also assessed.

• 대한기계학회논문집
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• 제12권5호
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• pp.1197-1205
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• 1988

본 연구에서는 피스톤운동을 톱날파로 근사하였을 때 단열된 실린더를 갖는 스터링기관에 대한 해석적인 해를 구하고자 한다. 실제기관에서 피스톤운동은 기구 학적 구동기구에 따라 상이하지만 대략적으로 정현파가 되며, 이 경우에는 해석적인 해가 존재하지 않으므로 수학적으로 구간선형적인 톱날파로 근사하였다. 비록 이러 한 근사를 도입한 단열해석이라 하더라도 해석적인 해가 존재한다면 등온해석보다는 기관성능의 예측에 더욱 적합함은 당연하다.

• 수산해양기술연구
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• 제43권1호
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• pp.1-11
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• 2007

It is the basic studies for productivity improvement and laborsaving of purse seine fishery. Because the seine shape is apt to be transformed in seine shooting process due to the effect of tide, this study is intended to establish 4 steps, whose flow velocity are 0, 2, 4 and 6cm/sec, in flume tank and perform the experiment to review the character. We used two model seines designed on the scale of 1 to 180 based on the power block seine, which is the mackerel purse seine generally used in the near sea of Jeju Island and triplex seine, which is the mackerel purse seine of one boat system fishing expected in the future, for the experiment, analyzed of the sinking movements on the two seines and its results are as follows. In the setting over the flow velocity 6cm/sec, experiment was impossible because of flying and transformation of seine were severe. The sinking movements of P seine and T seine generally showed linear phenomenon and the sinking speed showed gentle curve shape. Sinking tendency was distinguished by existence of flow velocity. When there is flow velocity, it showed the phenomenon that it sinking by similar type. Although sinking depth and sinking speed did not show distinguished classification, P seine shows bigger than T seine. When there was in flow velocity, the elapsed time(Et) and sinking depth (PDp, TDp) of P seine and T seine can be shown such experimental equations as PDp=(0.21V+4.96)Et-(0.62V-0.10) and TDp=(0.19V+4.95)Et-(0.72V+0.34). When there was in flow velocity, the elapsed time and siking speed (PSp, TSp) of P seine and T seine can be shown such experimental equations as $PSp=-0.11Et^2+1.42Et+1.75\;and\;TSp=-0.11Et^2+1.41Et+1.37$.

• 한국화재소방학회논문지
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• 제18권1호
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• pp.1-6
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• 2004

감용제 limonene을 이용하는 EPS 자원 재활용 공정에 있어서, limonene - EPS 혼합 액체의 저장$.$취급시의 화재위험성 평가에 대한 기초 자료로 제시하고자 혼합물의 농도 및 시료양의 변화에 따른 최저발화온도를 측정하였고, 발화와 비발화 영역을 비교하였다. 발화온도를 예측하는데 있어서 가장 과학적인 원리로서 이용되고 있는 발화 지연 시간, 활성화 에너지 및 발화온도의 관계식을 선형회귀분석을 이용하여 ln t = 0.704/T-5.819로서 제시하였다. 또, 가연성 혼합물의 농도 변화에 따른 발화위험성을 예측하기 위하여 혼합물의 농도와 발화온도의 관계식을 비선형회귀분석을 이용하여 $T_m=248.32+69.27X+172.60X^2$로서 제시하였다. 그 결과, 발화 지연 시간과 발화온도와의 관계식 및 혼합물의 농도와 발화온도와의 관계식에 의해서 limonene - EPS 혼합물의 발화온도의 추정이 가능하게 되었다.

• Nutrition Research and Practice
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• 제11권4호
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• pp.334-339
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• 2017

BACKGROUND/OBJECTIVES: Telomere length is a useful biomarker for determining general aging status. Some studies have reported an association between alcohol consumption and telomere length in a general population; however, it is unclear whether the alcohol flush reaction, which is an alcohol-related trait predominantly due to acetaldehyde dehydrogenase deficiency, is associated with telomere length. This cross-sectional study aimed to evaluate the associations of alcohol consumption and alcohol flush reaction with leukocyte telomere length (LTL). SUBJECTS/METHODS: The study included 1,803 Korean adults. Participants provided blood specimens for LTL measurement assay and reported their alcohol drinking status and the presence of an alcohol flush reaction via a questionnaire-based interview. Relative LTL was determined by using a quantitative polymerase chain reaction. Statistical analysis used multiple linear regression models stratified by sex and age groups, and potential confounding factors were considered. RESULTS: Age-specific analyses showed that heavy alcohol consumption (> 30 g/day) was strongly associated with a reduced LTL in participants aged ${\geq}65years$ (P < 0.001) but not in younger participants. Similarly, the alcohol flush reaction was associated with a reduced LTL only in older participants who consumed > 15 g/day of alcohol (P < 0.01). No significant alcohol consumption or alcohol flush reaction associations with LTL were observed in the sex-specific analyses. CONCLUSIONS: The results suggest that older alcohol drinkers, particularly those with the alcohol flush reaction, may have an accelerated aging process.

• Geomechanics and Engineering
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• 제14권2호
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• pp.161-174
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• 2018

The present study investigates the soil-structure interaction (SSI) effects on the seismic performance of smart base-isolated structures. The adopted control algorithm for tuning the control force plays a key role in successful implementation of such structures; however, in most studied carried out in the literature, these algorithms are designed without considering the SSI effect. Considering the SSI effects, a linear quadratic regulator (LQR) controller is employed to seismic control of a smart base-isolated structure. A particle swarm optimization (PSO) algorithm is used to tune the gain matrix of the controller in both cases without and with SSI effects. In order to conduct a parametric study, three types of soil, three well-known earthquakes and a vast range of period of the superstructure are considered for assessment the SSI effects on seismic control process of the smart-base isolated structure. The adopted controller is able to make a significant reduction in base displacement. However, any attempt to decrease the maximum base displacement results in slight increasing in superstructure accelerations. The maximum and RMS base displacements of the smart base-isolated structures in the case of considering SSI effects are more than the corresponding responses in the case of ignoring SSI effects. Overall, it is also observed that the maximum and RMS base displacements of the structure are increased by increasing the natural period of the superstructure. Furthermore, it can be concluded that the maximum and RMS superstructure accelerations are significant influenced by the frequency content of earthquake excitations and the natural frequency of the superstructure. The results show that the design of the controller is very influenced by the SSI effects. In addition, the simulation results demonstrate that the ignoring the SSI effect provides an unfavorable control system, which may lead to decline in the seismic performance of the smart-base isolated structure including the SSI effects.