Construction of irregular-shaped concrete structures requires a lot of time and money. To reduce the cost and time, the F3D(Free-Form Formwork 3D Printer) technology was adopted in manufacturing EPS(Expanded Polystyrene) formwork for irregular-shaped concrete structure. To design EPS formwork precisely, lateral pressure acting on irregular-shaped formwork and deformation of EPS form liner should be evaluated. However, in current Korean formwork standard, there are no standards for irregular-shaped formwork as it includes a lot of complex variables. For this reason, several researchers developed 3-dimensional finite element analysis model to calculate lateral pressure exerted by fresh concrete. In this study, deformation of irregular-shaped EPS formwork and lateral pressure acting on formwork was examined using finite element analysis model.
Building materials are composed of very complex chemical compounds. The aims of this paper are to investigate the emission concentrations of indoor pollutants from new apartment house and the emission variation patterns during 75 days. The average value of total volatile organic compounds(TVOCs) concentration was 3,768 ㎍/㎥ in five new apartments. Major VOCs included toluene, ethylbenzene, m,p-xylene and o-xylene. The average concentrations of each compound were measured as : benzene(58㎍/㎥), toluene (793㎍/㎥), ethylbenzene(438㎍/㎥), styrene(79㎍/㎥), m,p-xylene(1,210㎍/㎥), o-xylene(364㎍/㎥). The results indicated that the major VOCs from the new apartment were affected by building products such as on aromatic hydrocarbon compounds. TVOCs emission are characterized as high emission level at initial time (12,856㎍/㎥) and decreased through time. After a lapse of 75 days in sample house, TVOCs concentration decreased in about 20 times as compared with the initial concentration. The TVOCs emission profiles strongly depended on the generation mode and the concentration of the VOCs in building material.
This study was conducted to analyze the difference of body types within and between wild and farmed populations of olive flounder Paralichthys olivaceus using measured records of morphological traits. The results showed that surveyed traits and standard deviation were of body weight, of total length, and of body length. Also body height, body shape index and condition factor were , and , respectively. As result of least squares mean and standard error for each trait assumed in this study, those of farmed population showed significantly higher than those of wild population in all traits, exclusively in total length and body length (p<0.01). Particularly, the values of the body height and the body weight of the farmed population were higher than those of the wild population in the same total length. And the phenotypic correlation coefficients of the body weight, the total length, the body length and the body height showed strong positive correlation in all populations. These result suggested that morphological differences exist in farmed and wild flounder. Therefore, introduction of wild flounder is essential for the future production to improve the body type of farmed flounder, and parental fish should be chosen by considering selection of commercially important traits in the production process.
홍수사상은 크게 첨두홍수량, 홍수용적, 지속기간 등과 같은 서로 상관된 세 가지의 요소로 정의될 수 있다. 그러나 그동안 수공학적 계획이나 설계, 운영 등을 위한 홍수빈도해석에서는 주로 첨두홍수량 한가지 요소에 초점을 맞추어 홍수빈도해석을 수행해 왔다. 이러한 단변량 홍수빈도해석은 서로 상관된 홍수사상 사이의 복잡한 확률적 거동을 분석하는 데 있어 한계를 가지고 있다. 따라서, 본 연구에서는 Gumbel 혼합모형을 이용한 이변량 홍수빈도해석을 수행하여