• Journal of Korean Society of Steel Construction
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• v.14 no.6
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• pp.783-791
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• 2002

An improved formulation for multi-objective optimization was proposed. This formulation was applied to steel seismic loads. The multi-objective optimization problem was formulated with minimum structural weight, maximum strstability. The global criterion method was employed to find a rational solution closest to the ideal solution for the optimization problem using standard steel profile, To efficiently solve the optimization problem, the decomposition meth both system-level and element-level was used. In addition, various techniques including efficient reanalysis technique intermediate variables and sensitivity analysis using an automatic differentiation(AD) were incorporated. Moreover the reamong section properties fitted to the section profile used in order to link the system level and the element level. From numerical investigation, it could be stated that the proposed method will lead to the more rational design compared with one.

• Journal of Korean Society of Steel Construction
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• v.14 no.6
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• pp.721-728
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• 2002

Modern structrues are being built using high-strength and light-weight construction materials resulting in decreased structural mass and damping properties. Rhythmic activities such as jumping, dancing and clapping during lively concerts can produce excessive vibration of steel structures. In this study, dynamic load factors that occur during lively concerts were presented through vibration test and real-time monitoring of an existing concert hall. The vibration test included modal analysis and jumping test according to the forcing frequencies and the number of participants. Dynamic load foactors were acquired directly from peak acceleration responses of each harmonics. Comparing NBCC 1995, the 3rd harmonic must be included in the design of concert halls. Dynamic load factors must be increased as a result of the vibration test.

• Journal of Korean Society of Steel Construction
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• v.24 no.4
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• pp.411-422
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• 2012

The purpose of this study is to evaluate the flexural and shear capacity of steel wire-integrated void deck plate slabs. In order to evaluate flexural and shear capacity, we make five 150mmspecimens and three 200mmspecimens by slab depth as main variable. Each series of specimen is comprised of an existing steel wire-integrated deck-plate slab and two specimens using topping depth as variable. From the series of experiments, steel wire-integrated void deck plate slabs has any decline in flexural and shear performance. Therefore, a void-deck-plate slab which inserts Omega-steel plate showed reducing a using concrete-volume and had flexural and shear capacity following existing steel wire-integrated deck-plate.

• Journal of Sericultural and Entomological Science
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• v.36 no.2
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• pp.157-161
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• 1994

To investigate the morphology of Bacillus thuringiensis crystal proteins, two type crystal protein genes, cryIA(c) gene under the control of cryIA(b) gene promoter and cryIIA gene under the control of its own promoter, were transformed in B. thuringiensis acrystalliferous mutant strain and the transformants were characterized by SDS-PAGE and scanning electron microscopy. The expression and formation of crystal proteins in B. thuringiensis subsp. kurstaki Cry-B revealed that crystal proteins appear to have same molecular weight and morphology to those of wild type strain's, suggesting that the expression and formation of crystal proteins affected not by host cell or recombination of cryIA(e) gene under the control of cryIA(b) gene promoter but by only structural fragment of protoxin.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.1
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• pp.35-48
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• 1995

To develop the optimal design method for the longline type scallop culturing facilities in the open sea numerical calculations and hydraulic model experiments are carried out for the stability and function optimization. Using the results for the motion and tension of the facilities, stable design concepts and effects of motion control system by vertical anchor and resistance discs art discussed. The results of this study that can be applied to the design are as follows: 1) Total external forces by design wave $(H_{1/3}\;=\;6,7\;m,\;T_{1/3}\;=\;12sec)$ at the coastal waters of Jumunjin for unit facility (one main line) are estimated to 5-20 tons, and required anchor weights are 10-40 tons in the case of 2-point mooring system. Though the present facilities are stable to steady currents, but is unstable to the extreme wave condition of return period of 10 years. 2) The dimensions and depth of array systems must be designed considering the ecological environments as well as the physical characteristics including the mooring and holding forces that are proportional to the length and relative depth of main line to wave length, and the number of buoys and nets. 3) Oscillation of the facility is influenced by water particle motion and the weight of hanging net, and is excited at both edge, especially at the lee side. To reduce the motion of the nets, the vertical anchoring system and the resistence disc method are recommended by the experimental results, 4) The damage of rope near the anchor by abrasion should be prevented using the ring-type connection parts or anchor chains.

• Journal of Ocean Engineering and Technology
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• v.17 no.2
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• pp.47-53
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• 2003

The development of new materials with light weight and high strength has become vital to the machinery, aircraft and auto industries. However, there are a lot of problems with developing such materials that require such expensive tools, as well as a great deal of time and effort. Therefore, the improvement of fatigue life through, the adoption of residual stress, is the main focus. The compressive residual stress was imposed on the surface according to each shot velocity(1800, 2200, 2600, 3000rpm) based on Shot-peening, which is the method of improving fatigue life and strength. By using the methose mentioned above, we arrived at the following conclusions; 1. The fatigue crack growth rate(da/dN) of the Shot-peened material was lower than that of the Un-peened material. In stage I, $\Delta$K$_{th}$, the threshold stress intensity factor, of the shot-peen processed material is high in critical parts, unlike the Un-peened material. Also m, fatigue crack growth exponent and number of cycle of the Shot-peened material was higher than of the Un-peened material. That is concluded from effect of da/dN. 2. Fatigue life shows more improvement in the Shot-peened material than in the Un-peened material. Compressive residual stress of the surface on the Shot-peen processed operate resistance force of fatigue crack propagation.

• Journal of the Korean Institute of Landscape Architecture
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• v.34 no.6 s.119
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• pp.39-53
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• 2007

Unlike conventional roof landscaping, where various kinds of plants and structures are employed, a grass roof is a roof on which herbaceous plants are grown in planting medium and which is not accessed or maintained, mainly because it doesn't have sufficient load capacity to support a regular roof garden. They are mostly built on existing roofs, whether flat slab or gabled. Planting on roofs has numerous advantages, such as creating a biotope, purifying urban air, adding moisture to the atmosphere, storing rain water, preventing flash floods, reducing energy use for heating and air conditioning, enhancing the urban landscape and providing relaxation to the city dwellers, not to mention the alleviation of global warming by absorbing $CO_2$. In addition to the general merits of roof planting, the grass roof has its own unique qualities. Only herbaceous species are planted on the roof, resulting in light weight which allows roofs of existing buildings to be planted without structural reinforcement. The species chosen are mostly short, tough perennials that don't need to be maintained. These conditions provide an ideal situation where massive planting can be done in urban areas where roofs are often the only and definitely the largest space available to be planted. If roofs are planted on a massive scale they can play a significant role in alleviating global warming, heat island effects and energy shortages. Despite the advantages of grass roofs, there are some problems. The most significant problem is the invasion of neighboring plants. They may be brought in with the planting medium, by birds or by wind. These plants have little aesthetic value comparing to the chosen species and are usually taller. Eventually they dominate and prevail over the original species. The intended planting design disappears and the roof comes to look wild. Since the primary value of a grass roof is ecological, a change in attitude towards what constitutes beauty on the roofscape is necessary. Instead of keeping the roof neat through constant maintenance, people must learn that the wild grass with bird's nests on their roof is more beautiful as it is.

• Ocean and Polar Research
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• v.33 no.1
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• pp.35-43
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• 2011

Blubber plays different biological roles in cetaceans, including structural support, physiological demands (thermoregulation, streamlining, buoyancy, etc.), and energy storage. As such, biochemical composition, especially lipid, in the blubber may be vertically stratified in order to effectively assist with these functions. We analysed lipid content, class and fatty acid composition in the blubber of by-catch minke whale (Balaenoptera acutorostrata; n = 11), long-beaked common dolphin (Delphinus capensis; n = 3) and Pacific white-sided dolphin (Lagenorhynchus obiquidens; n = 2) from Korean waters. Lipid content for all three species ranged from 55 to 96% of wet weight, with a dominance of triacylglycerols. Vertical stratification of blubber lipid content was different between species. For minke whale and longbeaked common dolphin, it increased from inner (near the muscle) to outer (near the skin) layer, whereas it decreased for Pacific white-sided dolphin. Thirty-one fatty acids were found in all blubber samples and vertical stratification of fatty acid composition was similar among all three species. Among grouped fatty acids, monounsaturates were the most abundant, gradually increasing from inner to outer blubber layer, whereas polyunsaturates and saturates decreased. Such vertical stratification of lipid content and composition suggests that the modification and accumulation of lipid occur in the blubber itself in order to help cetaceans with their specific physiological needs.

• Tunnel and Underground Space
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• v.11 no.4
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• pp.344-351
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• 2001

In the tunnelling by blasting, the calculations of charge weight and the estimations of blasting effect have been simply carried out by empirical formulas. Also, it has been rare to consider the impact energy of blasting in numerical analyses. Thus in this study a numerical modeling technique of blasting load is developed and used with the 2 dimensional distinct element method(DEM) to consider the nonlinear behaviour of discontinuous underground structures. TD examine and verify its applicability of the numerical model to actual problems, a blasting of tunnel under an embankment is numerically analysed with DEM. It is examined that the behavior of circumference structures, the displacements of above- and under-ground structures, and the propagation of particle velocities can be known by this numerical analysis. As a result, the blasting load model, proposed by this study, can be applied to actual problems. This model applied with DEM can be used in the examination of structural stability.

• Journal of the Korean Society of Costume
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• v.62 no.2
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• pp.87-102
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• 2012

The purpose of this study is to identify conceptual constructs of well-being consciousness and appearance management behaviors, and to examine the effects of these two variables on attitudes toward Korean herbal cosmetics for Korean and Japanese consumers. A survey was carried out among female consumers between the ages of 20 and 50, and a total of 500 responses were analyzed by descriptive analysis, reliability test, t-test, and confirmatory factor analysis, structural equation modeling and multi group analysis. The results of this study were as follows: 1) The result of CFA and the reliability test on well-being consciousness and appearance management of Korean and Japanese respondents clearly showed factorial structures on each of the variant assessments. 2) In regards to the well-being consciousness, Korean and Japanese respondents highly tended to perceive well-being as a benefit to the physical health and an eco-friendly lifestyle respectively. In the area of appearance management, Korean and Japanese respondents had similar patterns that showed high scores of skin care and weight control. Both Korean and Japanese consumers showed favorable attitudes toward Korean herbal cosmetic products. 3) The consumers' well-being consciousness revealed to have positive influences on appearance management behavior. Both well-being consciousness and appearance management positively influenced attitudes toward Korean herbal cosmetics. 4) As a result of MGA, the well-being consciousness had more positive impacts on Korean respondents' attitudes toward Korean herbal cosmetics than the appearance management variable when compared to the Japanese respondents. On the other hand, appearance management had more positive impacts on Japanese respondents' attitudes to-ward Korean herbal cosmetics than well-being consciousness when compared to the Korean respondents. These results suggest that differentiated marketing strategies for Korean herbal cosmetics are crucial when targeting Korean and Japanese consumers.