• Korean Institute of Interior Design Journal
• /
• v.15 no.4 s.57
• /
• pp.46-54
• /
• 2006

The present study examined Marcos Novak, a digital architect who has researched digital architecture and produced related works since the early 1990s. Starting from digital ideas originating from science and mathematics, he pursued 'trans architecture' based on the concept of 'architecture beyond the boundary of architecture' and 'architecture as invisible foundation.' His concept of 'trans architecture' is considered an important viewpoint in expressing the architecture of a diversified and hybridized age like today. The objective of this study was to understand the concepts of Allobio and Eversion, which are important digital terms forming the background of Novak's trans architecture, and to analyze architecture philosophy and architecture design concepts observed in his works through Novak's digital terminology centering on the concept of trans architecture pursued by him. Through this, we purposed to analyze the concept of architectural space, methods of form creation and the characteristics of trans architecture space, which were unique to Novak, the leader of digital architecture, and ultimately to provide basic materials on Novak. Novak's trans architecture represents digital architecture in the contemporary diversified and hybridized age, and his works involve various different digital elements and ideas, scientific paradigms, mathematic algorithms, 4 dimensional geometry, etc. In this sense, he is regarded as a prominent leading advocate of digital architecture.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.27 no.12
• /
• pp.620-625
• /
• 2015

The summer climate is very hot and humid in Korea. Humidity is an important factor in determining thermal comfort. Recently, research on dehumidification device development has been attempted to save the energy required for operating the dehumidifier. Existing dehumidification systems have disadvantages such as wasting energy to drive the compressor. Meanwhile, dehumidification systems with membranes can dehumidify humid air without increasing the dry bulb temperature. Therefore. they don't have to consume cooling energy. In this paper, the installation conditions for a membrane system were analyzed to improve the shape and optimum performance of the system. The results showed that the distance between elements was the critical system design factor, and that a distance of 20 mm was the optimal condition for the pressure drop and flow characteristics of the internal air flow.

• Journal of the Korean Institute of Telematics and Electronics A
• /
• v.33A no.3
• /
• pp.140-151
• /
• 1996

In this paper, we analyze the variations of thermal characteristics of LD (laser diode) arrays packaged by a flip-chip bonding method. When we simulate the temperature distribution in LD arrays with a BEM (boundary element method) program coded in this paper, we find that thermal crosstalks in LD arrays packaged by the flip-chip bonding method increases by 250-340% compared to that in LD arrays packaged by previous methods. In the LD array module packaged by the flip-chip bonding technique without TEC (thermo-electric cooler), the important parameter is the absolute temperature of the active layer increased due cooler), the important parameter is the absolute temperature of th eactiv elayers of LD arrays to thermal crosstalk. And we find that the temperature of the active layers of LD arrays increases up to 125$^{\circ}C$ whenall four LDs, without a carefully designed heatsink, are turned on, assuming the power consumption of 100mW from each LD. In order to reduce thermal crosstalk we propose a heatsink sturcture which can decrease the temeprature at the active layer by 40%.

• Nuclear Engineering and Technology
• /
• v.37 no.2
• /
• pp.201-206
• /
• 2005

Fretting, which is a special type of wear, is defined as small amplitude relative motion along the contacting interface between two materials. The structural integrity of steam generators in nuclear power plants is very much dependent upon the fretting wear characteristics of Inconel 690 U-tubes. In this study, a finite element model that can simulate fretting wear on the secondary side of the steam generator was developed and used for a quantitative investigation of the fretting wear phenomenon. Finite element modeling of elastic contact wear problems was performed to demonstrate the feasibility of applying the finite element method to fretting wear problems. The elastic beam problem, with existing solutions, is treated as a numerical example. By introducing a control parameter s, which scaled up the wear constant and scaled down the cycle numbers, the algorithm was shown to greatly reduce the time required for the analysis. The work rate model was adopted in the wear model. In the three-dimensional finite element analysis, a quarterly symmetric model was used to simulate cross tubes contacting at right angles. The wear constant of Inconel 690 in the work rate model was taken as $K=26.7{\times}10^{-15}\;Pa^{-1}$ from experimental data obtained using a fretting wear test rig with a piezoelectric actuator. The analyses revealed donut-shaped wear along the contacting boundary, which is a typical feature of fretting wear.

• Journal of Korea Game Society
• /
• v.11 no.6
• /
• pp.13-22
• /
• 2011

In the digital media environment, the convergence is in the progress creating the new service and contents by users and developing the new needs of users by the service and contents as well. Social games are actualizing the new meaning of convergence. shows not only a new situation blurring the boundary of work and leisure, labor and playing and private and public sector, but how meaningful it is to make connection of social interactions and social assets a solid network. As the most popular social game text, reveals how the personal connections and personal networks constructs the social capital by making the ritual communication more interesting and flexible to the social gamers.

• Journal of Ocean Engineering and Technology
• /
• v.2 no.2
• /
• pp.104-111
• /
• 1988

This paper deals with the micro-surface-cracks behavior on the unnotched smooth specimens of Type 304 stainless steel at $593^{\circ}C$ in air under creep and creep-fatigue conditions that have 10 mim and 1 min load holding times respectively. The behaviors of the micro-surface-cracks have been visualized by means of surface replica method and optical micro-photography. The quantitative characteristics of initiation, growth and coalescence of micro-surface-cracks have been investigated by observing and measuring the crack growth behaviors. some of the important results are as follows: Main crack initiates at grain boundary in the early stage(10 to 20%)of its life time and grows through coalescence and finally leads to fracture. The distribution of micro-surface-crack length, 2a, can be plotted against the composite Weibull distribution. The growth rate of the main crack can be plotted against the stress intensity factor, crack tip opering displacement and J integral.

• Journal of Korean Association for Spatial Structures
• /
• v.16 no.2
• /
• pp.39-45
• /
• 2016

Membrane structure is a system that is stabilized by maintaining a tensile state of the membrane material that originally cannot resist the bending or pressure. Also, it is a system that allows the whole membrane structure to bear external loads caused by wind or precipitation such as snow, rain and etc. Tension relaxation phenomenon can transpire to the tension that is introduced to the fabric over time, due to the innate characteristics of the membrane material. Thus, it is important to accurately understand the size of the membrane tension after the completion of the structures, for maintenance and management purposes. The authors have proposed the principle of theoretically and indirectly measuring the tension by vibrating the membrane surface with sound waves exposures against the surface, which is compartmentalized by a rectangular boundary, and by measuring the natural frequency of the membrane surface that selectively resonates. The authors of this paper measured the tension of preexisting membrane structure for its maintenance by using the developed portable measurement equipment. Through analyzing the measurement data, the authors review the points that should be improved and the technical method for the new maintenance system of membrane tension.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2009.09a
• /
• pp.1360-1364
• /
• 2009

Necessity of removable soil nailing has been arisen in the soil nailing system because of problem such as civil petition for geotechnical environment and invasion of the ground boundary line and payments for use besides geotechnical engineering. Removable soil nailing system is improved soil nailing system that fixed socket arranged in boring hole for increasement of skin friction. In this study, field pull-out tests are carried out more 4 times considering installed distance of fixed socket and analyze skin friction behavior characteristics in fixed socket through analysis of measurements of strain gauge attached to fixed socket. Also, to evaluate application for wedge type removable soil nailing system analyzing displacement aspects through field pull-out tests by trial construction.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2008.10a
• /
• pp.1029-1037
• /
• 2008

The finite element analysis of transient water flow through unsaturated soils was used to investigate effects of hydraulic characteristics, initial relative degree of saturation, methods to consider boundary condition, and rainfall intensity and duration on water pressure in slopes. The finite element method with shear strength reduction technique was used to evaluate the stability of slopes under rainfall. The slope-related disasters in Korea usually occur between July and September during the typhoon and localized heavy rain. This means that the rainfall is the most important factor that leads to the slope-related disasters. The slope-related disasters can happen at very short time and lead to big damage. To forecast the change of the heave of the groundwater in slope the Seep/w program was used.

• Journal of the Korean Society of Safety
• /
• v.7 no.1
• /
• pp.39-45
• /
• 1992

The impulsive stress and wave propagation of a glass/epoxy laminate subjected to the transverse low-velocity impact of a steel ball are investigated theoretically and experimentally. A plate finite element model based on Whitney and Pagano's theory In consunchon with experimental contact laws is used for the theoretical investigation. The specimens fo, statical indentation and impact test we composed of ［0/45/0/-45/0］$_{2s}$ and ［90/45/90/-45/90］$_{2s}$ stacking sequences and have clamped-simply supported boundary conditions. Finally, these two results are compared and then the impulsive stress and wave propagation characteristics of this laminated composite are studied.ied.