Generally, antiseptic synthetic woods are used in septic environment because of their durability and relatively fine view. However, they have problems such as a failure of connection between the members under the septic conditions. In this study we investigate a fiber reinforced polyurethane foothold to be used in the wet environment to replace the synthetic wood. The fiber reinforced polyurethane foothold is consist of 2 different layer of materials. First layer is a glass fiber reinforced polymeric plastics (GFRP) which is located at outer surface of the foothold. This GFRP outer layers carry most parts of load. Second layer is a polyurethane layer which transfers the load to each outer layer. Flexural tests for this foothold are conducted. From the flexural tests it is confirmed that the structural performance of foothold test specimen with different number of GFRP layers and density of the polyurethane.

PURPOSES : Nowadays, cavity phenomena occur increasingly in pavement layers of downtown areas. This leads to an increment in the number of potholes, sinkholes, and other failure on the road. A loss of earth and sand from the pavement plays a key role in the occurrence of cavities, and, hence, a structural-performance evaluation of the pavement is essential. METHODS: The structural performance was evaluated via finite-element analysis using KPRP and KICTPAVE. KPRP was developed in order to formulate a Korean pavement design guide, which is based on a mechanical-empirical pavement design guide (M-EPDG). RESULTS: Installation of the anti-freezing layer yielded a fatigue crack, permanent deformation, and international roughness index (IRI) of 13%, 0.7 cm, and 3.0 m/km, respectively, as determined from the performance analysis conducted via KPRP. These values satisfy the design standards (fatigue crack: 20%, permanent deformation: 1.3 cm, IRI: 3.5 m/km). The results of FEM, using KICTPAVE, are shown in Figures 8~12 and Tables 3~5. CONCLUSIONS: The results of the performance analysis (conducted via KPRP) satisfy the design standards, even if the thickness of the anti-freezing layer is not considered. The corresponding values (i.e., 13%, 0.7 cm, and 3.0 m/km) are obtained for all conditions under which this layer is applied. Furthermore, the stress and strain on the interlayer between the sub-grade and the anti-freezing layer decrease gradually with increasing thickness of the anti-freezing layer. In contrast, the strain on the interlayer between the sub-base and the anti-freezing layer increases gradually with this increase in thickness.

In this paper, the full-size structural performance test for a lightweight soundproof tunnel composed of partitioned pipe truss members is carried out to investigate the structural performance. In addition, a nonlinear structural analysis of the same finite element model as the full-size testing model is performed to compare the test result. The test and analysis results showed that the lightweight soundproof tunnel ensures the structural safety against wind loads, snow loads and load combinations. As a result, the full-size test and analysis results m

The industrialization and urbanization forced to increase the density of pipelines such as water supply, sewers, and gas pipelines. The materials used for the existing pipe lines are mostly composed of concretes and steels, but it is true that the development for more durable and efficient materials has been continued performed to produce long lasting pipe lines. Recently, underground pipes serve in diverse applications such as sewer lines, drain lines, water mains, gas lines, telephone and electrical conduits, culverts, oil lines, etc. In this paper, we present the result of investigation pertaining to the structural behavior of unplasticized polyvinyl chloride (PVC-U) flexible pipes buried underground. In the investigation of structural behavior such as a ring deflection, pipe stiffness, 4-point bending test, experimental and analytical studies are conducted. In addition, pipe stiffness is determined by the parallel plate loading tests and the finite element analysis. The difference between test and analysis is about 8% although there are significant variations in the mechanical properties of the pipe material. In addition, it was found by the 4-point bending test there is no problem in the connection between the pipes by coupler.

In this paper, we present the result of analytical investigation pertaining to the structural behavior of steel-concrete composite plate girder with arch-type web stiffener. In the arch-type web stiffener located in the compression side of web, infill concrete is cast to strengthen the arch-type stiffener and also to exert resisting force against compression force. This type of composite steel-concrete plate girder bridge is built and is in service. To understand the behavior thoroughly, analytical parametric study was conducted by using the finite element method. As a result it was found that the effect of arch-type stiffener with infill concrete is considerable for the design of such type composite girder bridge.

The structural aesthetics of architecture are becoming an inspirational source for many fashion designers and have been reborn in structural fashion. This study planned to analyze the method of expression of structural aesthetics expressed in modern structural fashion design and the construction method to maximize such an effect on the basis of the construction characteristic of Santiago Calatrava as the representative architect of the structural aesthetic. According to the study, the structural aesthetics expressed in modern structural fashion design are as follows: 1) The symbolical formative aesthetic expressed by symbolical inference and analyzation; 2) the dynamic beauty of physic expressed by visual emphasis and dynamics; and 3) the asymmetric beauty of symmetry expressed by metastasis toward the boundary between balance and imbalance. In addition, to maximize structural aesthetics, we used repetition and a progressive technique based on rhythm, asymmetry, and incision-based variances, such as balance, polygon flux, and inference, and analyzation-based distortion as the structuring principle. The following expression methods for maximizing structural aesthetics were found: 1) symbolical and structural exaggeration of appearance; 2) detail technique expansion and material property diversification; and 3) the three-dimensional transformation of structure and shell expression. Structural fashion design was found to have maximized structural aesthetics by using such expression methods to secure artistic esthetics, destroy existing shapes and patterns, and create unique shapes.

현대사회는 조직구성원들의 혁신을 요구하는 지식기반 사회이며, 인적자원의 관리와 혁신이 기업의 경 쟁력을 높이는 중요한 요인으로 작용하고 있다. 이러한 상황에서 기업조직은 구성원들의 혁신을 지향하 는 적극적인 리더십의 발휘를 통해 구성원들의 바람직한 행동을 이끌어 내고, 이를 매개할 수 있는 요인 을 찾기 위한 노력을 해야 한다. 이에 본 연구의 목적은 리더십의 효과성에 대한 연구의 필요성이 제기 되고 있는 리더의 감성지능과 리더의 진정성이 부하의 셀프리더십 및 부하의 혁신행동에 어떠한 영향을 미치는지와 이러한 리더의 감성지능 및 리더의 진정성이 부하의 혁신행동에 미치는 영향력에 대한 부하 의 셀프리더십 매개효과를 검증하기 위한 것이다. 이러한 연구 목적을 위해 부산과 경남의 13개 제조기업 317명의 구성원을 대상으로 실증연구를 실시하였다. 연구결과, 첫째, 리더의 감성지능과 리더의 진정성은 각각 부하의 혁신행동에 긍정적인 정(+)의 영향을 미치고 있음이 확인되었다. 둘째, 리더의 감성지능과 리더의 진정성은 각각 부하의 셀프리더십에 긍정적인 정(+)의 영향을 미치고 있음이 확인되었다. 셋째, 부하들의 셀프리더십이 혁신행동에 유의한 긍정적 정(+)의 영향을 미치고 있음을 검증하였다. 넷째, 리더 의 감성지능과 부하의 혁신행동 간의 관계 및 리더의 진정성과 부하의 혁신행동의 관계에서 부하의 셀프 리더십 매개효과를 검증한 결과, 각 관계별로 부하의 셀프리더십의 매개효과가 있음을 검증하였다. 이는 부하의 셀프리더십이 리더십과 부하의 혁신행동의 관계에 적극적인 영향을 미치고 있음을 알 수 있다. 본 연구는 리더의 감성지능과 진정성이 부하의 셀프리더십을 매개로 부하의 혁신행동에 영향을 주고 있다는 종합적인 새로운 모델을 제시하였다는 이론적 시사점과 조직에서 구성원들의 혁신행동을 강화하 기 위해서는 리더의 감성지능과 진정성, 그리고 부하의 셀프리더십의 역할이 중요하다는 실무적 시사점 을 제공한다. 마지막으로 본 연구의 한계와 향후연구 방향을 제시하였다.

Cheomseongdae is the masonry stone structure with the cultural and historical values. But, this structure has the various damages such as cracks, gaps, slope variations and ground subsidence. So, the interests for the safety security in the structural parts have been increased. Therefore, this study performs the structural modelling which considers the several damage cases, and then evaluates the structural behavior characteristics through the discrete element analysis. Especially, this study checks the swelling and displacement gap of the whole structure and the separation between the neighboring members.

음이온 교환막의 치환체 특성을 파악하기 위하여 탄화수소의 분자구조가 다른 세 종류의 음이온 교환기를 vinyl benzyl chloride (VBC) base 막에 도입하였다. 지방족계로 trimethylamine (TMA), 고리형계로 N-methylpiperidine (MP), 방향족계로 pyridine (Py)은 아민화 반응을 통하여 도입되었다. 각각의 반응속도는 막저항(MER)과 이온교환능력(IEC) 변화의 관측으로부터 Py < MP < TMA의 순서로 반응하고 있음을 보여주었다. 한편 SEM image에서는 Py 치환체 막이 가장 균일하고 치밀한 구조를 보여주었으며, 전기화학적 특성에서도 Py이 상용막(AMX)과 비슷한 막저항(5.0 Ω·cm2 >, in 0.5 mol/L NaCl)을 나타내었다. 이 모든 결과로부터 치환체의 공명구조는 균질한 이온교환막의 제조에 기여하고 있음을 알 수 있었다.

GRP pipe (Glass-fiber Reinforced Plastic Pipe) lines making use of FRP (Fiber Reinforced Plastic) are generally thinner, lighter, and stronger than the existing concrete or steel pipe lines, and it is excellent in stiffness/strength per unit weight. In this study, we present the result of field test for buried GRP pipes with large diameter(2,400mm). The vertical and horizontal ring deflections are measured for 387 days. The short-term deflection measured by the field test is compared with the result predicted by the Iowa formula. In addition, the long-term ring deflection is predicted by using the procedure suggested in ASTM D 5365(ANNEX) in the range of 40 to 60 years of service life of the pipe based on the experimental results. From the study, it was found that the long-term vertical and horizontal ring deflection up to 60 years is less than the 5% ring deflection limitation.

최근, 우리나라는 겨울철 콘크리트 포장에 제설을 목적으로 한 제설제의 사용량이 점차적으로 증가하 고 있는 추세이다. 예를 들어 서울시의 경우, 현재 연간 약 4만톤 이상의 제설제가 도로포장에 살포되고 있으며, 이는 5년 전과 비교하여 약 2.5배 이상 제설제의 사용량이 증가한 것으로 보고되고 있다. 뿐만 아니라, 제설제 살포에 따른 콘크리트 포장의 표면박리(scaling) 등과 같은 내구성 저하 현상이 빈번하게 발생함에 따라 콘크리트 포장의 성능에 대한 제설제 종류 및 농도의 영향에 대한 관심도 점차 증가되고 있는 실정이다. 특히, 우리나라는 도로포장의 제설을 위하여 염화칼슘수용액 및 고체 염화나트륨을 이용 한 습염살포방식이 널리 사용되고 있다. 주지하다시피, 염화물계 제설제의 사용은 철근부식에 의한 콘크 리트의 손상을 초래할 수 있으며, 겨울철 동결융해 반복작용에 의한 콘크리트의 표면박리작용의 주요 원 인이 된다. 본 연구에서는 강도가 상이한 콘크리트(24 및 35 MPa)를 제조하여 ASTM C 672에 준하여 스케일링 실험을 실시하였으며, 동결융해 작용 50싸이클 후 콘크리트의 열화원인을 분석하기 위한 SEM 및 EDS 분석을 실시하였다. 실험결과에 의하면, 콘크리트의 스케일링 저항성은 강도등급에 따라 상이하였으며, 동결융해 반복작용에 따른 thaumasite의 생성이 스케일링의 주요 원인 중 하나라고 판단된다.

As the designated name, adenocarcinoma, not otherwise specific (ANOS) revealed lack of histomorphologic characteristics that could classify the tumors under specific name. ANOS had nothing in common with other salivary gland malignancies, but glandular differentiation. The purpose of this study is to find out the solid characteristics of ANOS on the base of cytological and architectural features. 20 ANOS cases were studied. We identified 20 patients with salivary adenocarcinoma, not otherwise specified, ranging in age from 26 to 76 years (median, 53.85 years), with slight female predilection (female 11: male 9). The minor salivary gland was the most common site of tumor origin, especially on the palatal area (11 out of 20). The size of tumor was from 1.0 to 7.0(median 3.07). For the histopathological analysis, we classified the tumors by cytological and architecture patterns. Basaloid and epitheloid cytological patterns were showed with solid, microcystic/pseudocystic architecture. We found invasive growth patterns in 7 out of 20 cases. Reviewing and classifying the common features of ANOS could be helpful to make a diagnosis of malignant salivary gland tumors.

This study empirically examines how much effect levels of fatigue and stress of a construction worker have on disaster risks from the perspective of human factors concerning construction disaster risks. To achieve the purpose of this study, a survey was conducted with respect to construction workers working at large construction sites within the metropolitan area. The retrieved survey data were analyzed by using the statistical software programs, SPSS 18.0 and AMOS 8.0. The results of this study do not definitively lead to the conclusion that the level of fatigue or stress of construction workers result in disaster risks. However, it does show that the results vary depending upon the individual approach and treatment of stress and fatigue. In particular, this study revealed that disaster risk levels could increase through unsafe behavior intentions which were established as a mediator variable. Also, with respect to unsafe behavior intentions of construction workers leading to disaster risks, when examining the results that the level of mental fatigue, occupational stress and social-psychological stress of construction workers had a greater significant effect than the level of physical fatigue, this study demonstrates the importance of psychological and mental issues that could be easily overlooked with respect manual labor workers.

Due to rapid urbanization and industrialization, water supply and sewer line systems are also developed relevantly. Manhole is an essential component structure of the pipeline system. Manhole is a structure constructed to accommodate the direction, dimension, differences in level, and easy of maintenance in the pipeline system. In this paper we present the result of investigations pertaining to the structural behavior of PVC sewer manhole buried underground. In the paper mechanical properties of PVC material are reported. In addition, by the finite element analysis (FEA), we confirmed that a PVC double-wall corrugated pipe manhole, when it is buried underground, is safe for the stress as well as buckling strength if the manhole is constructed within the suggested limit of buried depth.

본 논문에서는 후기 근대라는 그늘 아래서 ‘돌봄 제공자’로서의 아버지 역할을 사회적으로 유발하는 구조적인 변동을 분석했다. 신자유주의가 강화되는 가운데 단독생계 부양자 역할이 무너지고 여성들의 유급 노동 비율이 높아지며 가족의 이혼율 증가와 같이 가족 불안정성이 증가할수록 ‘돌보미’로서의 아버지 역할은 사회적으로 강조됐다. 또한 국가의 차원에서 ‘아버지 할당제’와 같은 ‘돌봄 제공자’로 아버지를 바라보는 복지제도가 마련되고 아버지 운동에서는 돌봄 제공자로서의 권리 확보를 위해 노력했다. 이러한 구조적 변동을 배경으로 하여 아버지들은 놀이 및 교육자로서의 ‘돌보미’ 역할을 수행하며 자녀 돌봄 영역에 참여하고 있으며 이 과정에서 자녀와 친밀한 관계를 형성하고 감정 능력을 발달 시키는 새로운 경험을 하게 된다. 따라서 아버지들이 ‘돌보미’로서 변화하는 가운데 그들의 양육자로서의 역할은 더욱 강화되고 있다고 할 수 있다.

Metallic Cr film coatings of 1.2μm thickness were prepared by DC magnetron sputter deposition method on c-plane sapphire substrates. The thin Cr films were ammoniated during horizontal furnace thermal annealing for 10-240 min in NH3 gas flow conditions between 400 and 900˚C. After annealing, changes in the crystal phase and chemical constituents of the films were characterized using X-ray diffraction (XRD) and energy dispersive X-ray photoelectron spectroscopy (XPS) surface analysis. Nitridation of the metallic Cr films begins at 500˚C and with further increases in annealing temperature not only chromium nitrides (Cr2N and CrN) but also chromium oxide (Cr2O3) was detected. The oxygen in the films originated from contamination during the film formation. With further increase of temperature above 800˚C, the nitrogen species were sufficiently supplied to the film's surface and transformed to the single-phase of CrN. However, the CrN phase was only available in a very small process window owing to the oxygen contamination during the sputter deposition. From the XPS analysis, the atomic concentration of oxygen in the as-deposited film was about 40 at% and decreased to the value of 15 at% with increase in annealing temperature up to 900˚C, while the nitrogen concentration was increased to 42 at%.

Recently, environmental problems associated with the excessive use of fossil fuel are hot issue throughout the world. As an alternative energy resource, the importance of renewable energy is continuously rising. Especially, growth rate of photovoltaic energy generation is one of the best. In this paper, floating PV generation system made of pultruded fiber reinforced polymeric plastic (PFRP) is discussed. It is well known that PFRP has many advantages such as high corrosion resistance, high specific strength/stiffness, etc. Compared with conventional construction materials. To investigate the structural behavior under flow induced dynamic loading, members and connections of members are tested under cyclic loading. It was found that the structural system is strong enough to resist such a cyclic loading.

To inject CO2 in geological formations, deep wells that penetrate the formations need to be constructed. The seal integrity of deep wells for CO2 leakage are enhanced by annulus cements. By injecting CO2, brine in formations can be carbonated and the potential degradation of annulus cement in the carbonated brine has been brought up. In this paper, Type G oil well cement (OWC) pastes are hydrated for 28 days. Conditions of geosequestration in a sandstone formation at a depth of roughly 1 km, was simulated by bubbling CO2 into a heated vessel containing brine. The hydrated OWC cylindrical specimens were exposed to this environment. Slices of the cement specimen were taken periodically, during and after exposure to quantify degradation progression. The elastic modulus of the specimens was examined prior to and after exposure. After 28 days of exposure, the degraded depth of specimen was measured as 4.137 mm. The elastic modulus of the specimens was measured as 2.2 GPa and 3.2 GPa prior to and after exposure respectively. Considering a composite action in the partially degraded specimen, the elastic modulus of degraded part can be extracted. The results indicated that the difference of elastic modulus in the partially degraded annulus cements could occur a composite action of deep wells subject to axial load and shear cracks would be generated due to the composite action.