• Journal of Internet Computing and Services
• /
• v.18 no.3
• /
• pp.29-36
• /
• 2017

In these days, 3D dynamic simulation is closely related to many industries. In the past, physically-based 3D simulation was used mainly in the car crash or construction related fields, but it also plays an important role in movies or games today. Many mathematical computations are needed to represent the 3D object realistically, but it is difficult to process a large amount of calculations for simulation of application based on CPU in real-time. Recently, with the advanced graphic hardware and improved architecture, GPU can be utilized for the general purposes of computation function as well as graphic computation. Many approaches using GPU have been applied for various research fields. In this paper, we analyze the performance variation of two cloth simulation algorithms based on GPU according to the change of execution properties of GPU shaders in oder to optimize the performance of GPU-based cloth simulation. Cloth simulation is implemented by the spring centric algorithm and node centric algorithm with GPU parallel computing using compute shader of GLSL 4.3. We compare the performance of between these algorithms according to the change of the size and dimension of work group. The experiment is repeated to 10 times during 5,000 frames for each test and experimental results are provided by averaging of FPS. The experimental result shows that the node centric algorithm is executed in higher speed than the spring centric algorithm.

• Journal of the Korea Convergence Society
• /
• v.8 no.8
• /
• pp.255-265
• /
• 2017

The study analyzed previous studies on traditional markets and market modernization projects to analyze research trends and content related to traditional markets. Next, the study selected 4 traditional markets throughout the nation where there was promotion of market modernization projects to conduct field research and interviews about store modules, line of flow, facility configuration, and types of businesses. Empirical comparative analysis was conducted on construction hardware status through measurement and observation and data was collected on business environment and requirement characteristics by business type through interviews with merchant associations of the corresponding markets. Consistent standard was applied as much it was possible to comparatively analyze the 4 market modernization cases and on the unique characteristics of individual markets, the cause was determined in conjunction to the history of the business promotion process and regional characteristics. After the study, basic data to suggest guidelines in store modules by business type in traditional markets could be acquired and the study identified the facilities equipment standards that must be considered in future market modernization projects. Through this it will be possible to derive policy implications to minimize trial and error and guarantee business efficiency in future market modernization projects.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.23 no.1
• /
• pp.9-17
• /
• 2009

Discomfort Glare from the artificial light sources is an important issue in assessment of lighting quality for healthy buildings. Glare, as a factor of the characteristics of brightness, which has been defined as the sensation produced by contrast and luminance within an entire field view, unfavorably influences the occupants who performs visual tasks. It may cause annoyance and discomfort by interruption of visibility. In the whole visual field, glare can be determined by effects of the position, the luminance and the size of the light source and brightness of the surroundings. Therefore, experimental equipment is required to maintain a constant visual lighting environment. Recent studies have been developed and used the instrument for glare sensation evaluation but the instruments showed some difficulties to verify the correlation of glare indicators. The instrument have been developed with reference to former studies. It is called the Glare Tester. This is consist of 2[m]-diameter vertical dome screen painted with white flat paint, and light sources installed inside the screen. These light sources can provide various range of brightness at any inner surface of the screen. 2 Glare light sources can provide the value of luminance within the range of $0{\sim}150,000[cd/m^2]$. Moreover, 12 light sources are used for background luminance and it can perform the value of luminance within the range of $0{\sim}350[cd/m^2]$. Several experiments have been conducted using this Glare Tester to evaluate the range of the visibility, the values of BCD and the glare sensation in lower and upper visual field.

• Journal of Conservation Science
• /
• v.32 no.3
• /
• pp.425-436
• /
• 2016

The Yakhyeon catholic church (Historic Site No. 252 in Korea) that was constructed in 1892 has been the first western brick structure to ever have existed and one of the most important historical materials in the Korean modern architecture. After a fire had broken out at the catholic church in 1998, the stained glass on the back wall, the slab glass (dalle de verre) introduced by Lee Nam Guy in 1974, was repaired in 1999 because of singe scorch and water leakage. An analysis of the coloration elements showed that yellow, red and green included Zn, K and Cd, respectively. The glass of red contained Se, dark green contained Mn and Cr, and blue contained Pb and S. According to material analysis, the masonry joint was identified dolomite ($CaMg(CO_3)_2$) and calcite ($CaCO_3$), which was observed plate, columnar, rhombic and square of crystalline particles. Meanwhile, ultrasonic velocity in the stained glass recorded low speed in the middle and lower right of the window (an average of 4,130 m/s). And the joint was measured the lowest physical properties of the top left and middle of the window (an average of 2,053 m/s). This study have showed that extensive physical damage was founded to the left and middle rather than the right side. In this respect, more research in needed to conserve the correlation between color and physical properties.

• Archives of design research
• /
• v.15 no.4
• /
• pp.177-188
• /
• 2002

A thousands of chairs have designed from the Victorian era to the present. Thonet's Nol4 chair in 1859, Wright's high-back chair in 1904, Ritveld's red/blue chair in 1917, Breuer's Wassily chair in 1925, Aalto's Paimio chair in 1932, Eames's DAR chair in 1948, Piero Gatti's Sacco chair in 1969, Starck's Von Volgelsang chair in 1984, Stumpf's Aeron Chair in 1992, Little's 'Coat of arms' chair in 1994 - the list of architects who have seized the opportunity to express their theories in the design of a chair is seemingly endless. Architects such as Machintosh(1868-1928), Wright(1807-1959), Aalto(1898-1976) included chairs within their artistic schemes for interiors and buildings. But as the manufacture of chairs moved away from the domain of the craftsman towards that of the industrial process, architects were also ideally positioned, with their background knowledge of engineering, to pioneer innovative chair design within the constraints of modern manufacturing technology. Beyond matters of function and structure, the fundamental worth of chairs, past or present, lies in their communication of attitudes, ideas and values. The persuasiveness of a chair depend on the clarity of its rhetoric. Chair has become an ideal medium for designers to make their visual statements and construct their individual manifestos. In chair design there is a ping-pong game played out between absurd and useful design, and this game is one way in which the design profession explores itself.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.2
• /
• pp.588-594
• /
• 2020

This study proposes non-destructive rebound-hardness and ultrasonic testing methods to more accurately evaluate the residual structural performance of reinforced concrete structures in a fire. Techniques are also proposed to assess the stiffness used in the deflection calculation with natural frequencies obtained by vibration tests. In the compressive strength evaluation using rebound hardness, the residual compressive strength of thick specimens and a larger water/cement (W/C) ratio were shown to be large. The homogeneity of concrete at high temperature compared to ambient temperature conditions was assessed by the velocity of ultrasonic waves that penetrate the concrete, and it followed W/C or thickness of slab makes little different results. To assess the stiffness of fire-damaged slabs and increase in deflection, the natural frequency was measured by vibration tests and incorporated into the equation of the stiffness. The application of this technique to the slab experiment showed that it can be a very reasonable evaluation technique. In addition, to evaluate the residual strength of a member after fire, a test of the strength of a component was carried out during and after heating.

• Journal of the Korean Institute of Traditional Landscape Architecture
• /
• v.33 no.1
• /
• pp.12-20
• /
• 2015

After the great King Munmu constructed Donggung-palace and Wolji-pond in 674, original landscape could not be estimated due to lack of related materials for some 1,250 years until it was surveyed in 1922. Accordingly, the study, to estimate changes of Wolji-pond landscape more accurately, analyzed the study of Hara(1932) and pictures in the Japanese ruling period etc. - these had not been studied so far. The study results are as follows. As a result of comparing survey maps of 1922 and one of 1975, it was found that during 53 years, whole area excluding island showed eroded part by 2~4m, severely, there was mounding area which was lowered by 10m. And it was identified through survey map of 1922 and pictures of the 1950's that inside southern shore protection of the No. 1 construction site were many landscape-stones(景石) which can make imagine a hill; here was water path. Trace of such path etc. remained just before excavation. 2) The construction site No. 3 and 5 in peak shape were higher than construction site No. 1, 2, and 4. Accordingly, there is high possibility that construction stood on high stylobate. So it is wrong that construction site No. 3 and 5 are restored in same height as other construction sites. Comprehensive restoration basic plan made in 2012 was also wrong. As a result of estimating changes of landscape through pictures before excavation of Wolji-pond, the author could identify changes of landscape in mound area and pumice stones which showed much changes in drawing. The study has limit due to lack of space. But if more pictures can be analyzed, it could further help for estimating original landscape of Wolji-pond.

• Journal of the Korea Concrete Institute
• /
• v.21 no.6
• /
• pp.763-771
• /
• 2009

As the demand on long span structures increases more in recent years, the excessive deflection, in addition to the ultimate strength, in horizontal members becomes a very important issue. For this reason, as an alternative method to effectively solve the deflection problems, the application of post-tensioned structural system with unbonded tendon increases gradually. However, most of the existing researches on post-tensioned members with unbonded tendons (UPT) focused on the ultimate flexural strength, which would be impossible or improper to check serviceability such as deflections. Therefore, this study aims at proposing a stress prediction model for unbonded tendons that is applicable to the behavior of UPT members from the very initial loading stages, post-cracking states, and service to ultimate conditions. The applicability and accuracy of the proposed model were also evaluated comparing to the existing test results from literature. Based on such comparison results, it was verified that the proposed model provided very good predictions on tendon stresses of UPT members at various loading stages regardless their different characteristics; wide range of reinforcement index, different loading patterns, and etc. The proposed model especially well considered the effect of various loading types on stress increases of unbonded tendons, and it was also very suitable to apply on the over-reinforced members that easily happened during strengthening/repairing work.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2008.11a
• /
• pp.333-336
• /
• 2008

As the high-rise building increase due to the gravitation of population to big cities recently, it requires high quality and high performance of Concrete. As a result, people are keenly interested in Meta-kaolin as new admixture favorable from an economic perspective, which has strength and endurance with admixture at the same level like Silicafume. Accordingly, as to Meta-kaolin, this study was to set by three levels like domestic one, foreign one, and Silicafume, the waterbinding material ratio 25%, and four level substitute like 0, 10, 20, and 30(%) in order to compare and analyze the quality characteristics of high-strength concrete according to the substitute of Meta-kaolin applicable with replacement of Silicafume. As a result of performing experiment, as to the higher the additive amount of Superplasticizing agents in order to secure target liquidity was, the more the substitute in each admixture increased. This study had a tendency that the Silicafume increased the additive amount of Superplasticizing agents with high fineness compared with Meta-kaolin. In addition, the higher the substitute in each admixture was, the more its strength increased On the strength property, the higher the substitute in each admixture was, the more its strength increased. This study has found out that the Meta-kaolin has shown the better strength than the one of Silicafume. On the other hand, the relationship between the Compressive strength and Elastic coefficient has shown the similar formula suggested from ACI363.

• Spatial Information Research
• /
• v.22 no.1
• /
• pp.65-73
• /
• 2014

Recently indoor navigation with indoor map such as Indoor Google Maps is served. For the services, constructing indoor data are required. CityGML and IFC are widely used as standards for representing indoor data. The data models contains spatial information for the indoor visualization and analysis, but indoor navigation requires semantic and topological information like graph as well as geometry. For this reason, IndoorGML, which is a GML3 application schema and data model for representation, storage and exchange of indoor geoinformation, is under standardization of OGC. IndoorGML can directly describe geometric property and refer elements in external documents. Because a lot of data in CityGML or IFC have been constructed, a huge amount of construction time and cost for IndoorGML data will be reduced if CityGML can help generate data in IndoorGML. Thus, this paper suggest practical use of CityGML including deriving from and link to CityGML. We analyze relationships between IndoorGML and CityGML. In this paper, issues and solutions for linkage of IndoorGML and CityGML are addressed.