• Journal of the Korean Solar Energy Society
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• v.23 no.1
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• pp.48-56
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• 2003

Three of the leading computer daylighting simulation programs are compared with physical modeling techniques as a means of predicting daylighting performance of interior spaces. Lumen-Micro, Adeline and Lightscape are compared with physical model experiments under clear sky conditions. The comparative evaluations are conducted on analysis of daylight illuminance ratio(%) depending on model types. The estimated average errors are analyzed on 9.4% in Lumen-Micro, 6.3% in Adeline and 3.4% in Lightscape. Therefore, it is proved that three programs are useful for evaluating daylighting performance in our clear sky condition.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.05a
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• pp.239-243
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• 2001

In evaluating sound performance of building, it is important to carry on tests and evaluations based upon residential sound performances. Korean Standards include test methods on sound performance, but don't include any code on evaluation methods. Therefore, evaluation methods from Japan or ISO have been used for evaluating sound performance in domestic so far. In this study, every regulation from ISO, JIS, ASTM, especially for airborne sound insulation against building and building element, is analyzed in order to apply to establishment of Korean Standards on a sound performance evaluation method in buildings.

• International Journal of High-Rise Buildings
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• v.1 no.3
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• pp.155-167
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• 2012

This paper introduces the outlines of review and approval processes, general criteria and usual practices taken in Japan for the seismic design of high-rise buildings. The structural calculations are based on time-history analyses followed by performance evaluations. This paper also introduces structural design of two high-rise buildings: one is a 100 m high reinforced concrete residential building, and the other is a 300 m high steel building for mixed use.

• Structural Engineering and Mechanics
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• v.65 no.3
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• pp.251-261
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• 2018

Self-centering concentrically braced frames (SCCBFs) are emerging as high performance seismically resistant braced framing system, due to the capacity of withstanding strong earthquake attacks and promptly recovering after events. To get a further insight into the seismic performance of SCCBFs, systematical evaluations are currently conducted from the perspective of modal contributions. In this paper, the modal pushover analysis (MPA) approach is utilized to obtain the realistic seismic demands by summarizing the contribution of each single vibration mode. The MPA-based results are compared with the exact results from nonlinear response history analysis. The adopted SCCBFs originate from existing buckling-restrained braced frames (BRBF), which are also analyzed for purpose of comparison. In the analysis of these comparable framing systems, interested performance indices that closely relate to the structural damage degree include the interstory drift ratio, floor acceleration, and absorbed hysteretic energy. The study shows that the MPA approach produces acceptable predictions in comparison to the exact results for SCCBFs. In addition, the high-modes effect on the seismic behavior increases with the building height, and is more evident in the SCCBFs than the BRBFs.

• 유체기계공업학회:학술대회논문집
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• 2004.12a
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• pp.70-77
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• 2004

Comprehensive investigation on the outlet's geometric shapes of a centrifugal blower with higher inlet resistance than an atmospheric pressure is carried out for improvements of its performance. Most unwanted behaviors of such blower are pulsating flows because of unbalance between inflows and outflows in a scroll casing. In order to reduce this undesirable phenomenon a triump is made for both the shape of outlet duct and an accessory structure inserted in the outlet port of the blower. The modification on the shape is concerned with the contraction of cross sectional area and the attached structure is for an intentional obstruction to cause a flow resistance. The details of the modification are examined for different cases and results. The methodologies for the work are performance evaluations including noise level and velocity measurements with PIV Consequently, the performance of improved system is close to that of the system operating with atmospheric pressure at the inlet.

• Proceedings of the Korea Society for Simulation Conference
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• 2005.11a
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• pp.13-18
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• 2005

Routers determine routing path considering network topology and link state information for providing QoS (quality of service) guarantee. Therefore, it is important that routers know link state information to calculate routing path. However, if routers generate link state update messages inordinately, their router performance are reduced due to the process of link state update messages. On the other side, in case that link state information is not updated appropriately, route setup requests can be rejected even though there exist routes. In this paper, we propose an algorithm to improve router performance and evaluate the proposed algorithm performance compare with conventional algorithm by simulations.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.10 no.3
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• pp.358-367
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• 1998

Since the performance of cooling tower is strongly dependent on the thermal performance of the packing, the evaluations of heat transfer rate and fan power from various packing have attracted intense interest. In the present study, two new packings have been devised and their performances have been compared with those of two existing packings to find better shape characteristic. It is found that one of the existing packings, which showed high heat transfer rate and medium fan power due to zig -zag flow passages and highly irregular surfaces, should be adapted.

• Educational Technology International
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• v.10 no.1
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• pp.107-135
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• 2009

The purpose of this paper is to review a variety of challenges facing the Human Performance Technology (HPT) in supporting knowledge workers' performance, and to explore possible HPT models for knowledge workers. The first section of this paper investigates the core attributes and major models of HPT as a foundation. While HPT has a lot of strengths in terms of systemic, systematic, methodologically eclectic, evidence based, and results oriented approaches, some pitfalls - which could be detected if these principles were mindlessly applied to problem areas - are explored. The second section presents some considerations such as analysis, intervention design, and leadership that HP technologists need to take in order to make HPT a better field of practice for knowledge workers. The author also suggests a tentative diagnostic model and a process model for knowledge workers, core principles of which are based on systems thinking, in particular Senge's the fifth discipline and Checkland's soft systems methodology. The importance of formative evaluations to improve these models is noted as a conclusion.

• Journal of Korean Society of Steel Construction
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• v.17 no.1 s.74
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• pp.33-43
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• 2005

This paper presents the test results and evaluations for the energy dissipation capacity and compressive performance of light-weight hybrid panels. A total of 26 full-scale specimens of light-weight hybrid panels were tested. The parameters include the presence of light-weight foamed mortar, the specific gravity of light-weight foamed mortar (0.6, 0.8, 1.0, 1.2), the finishing materials (light-weight foamed mortar, OSB [Oriented Strand Board], gypsum board), the shape of bracing (x, ~), and the size of panels (1P-900 mm 2,400 mm, 2P-1,800 mm 2,400 mm). The results of the cyclic tests are somewhat different from those of monotonic tests, due to the different specific gravity of light-weight foamed mortar. It was found from the compressive tests that the ultimate strength and initial stiffness are increased by means of light-weight foamed mortar (2~2.5 times in ultimate strength and 2~3 times in initial stiffness).

• Journal of the Korean Society of Environmental Restoration Technology
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• v.22 no.6
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• pp.97-114
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• 2019

This study aims to analyze the effect of urban ecosystem restoration projects by evaluating the short-term restoration performance of the project sites, from both qualitative and quantitative evaluations. In this study, for the qualitative evaluation, we derived the evaluation frame from previous studies and literature. For the quantitative evaluation, the changes in ecological connectivity after the restoration project were described using landscape permeability and network analysis. In addition, changes in habitat quality after the restoration project were evaluated by using InVEST Habitat Quality Model. These evaluations were applied to the three natural madang (ecological restoration) projects and two ecosystem conservation cooperation projects. As a result, three categories, 10 indicators, and 13 sub-indicators were derived from literature as the evaluation frame for this study. In the case of quantitative evaluation of restoration performance, habitat quality increased by 45% and ecological connectivity by 37% in natural-madang, and habitat quality by about 12% and ecological connectivity by about 19% in ecosystem conservation cooperation projects. This implies that the ecological restoration project can increase the ecological connectivity and the habitat quality of degraded sites even in a short period of time by improving the land-cover and land use. The results by applying the evaluation frame indicated that ecological and environmental factors and the ecological functions were improved by the restoration works, even though the magnitude of performances were diverse depending on the specific evaluation items, project type, and site characteristics. This study clarified that the success of ecological restoration project should be assessed by both of the short-term and long-term goals, which can be achieved by the maintenance and sustainable management, respectively.