• Architectural research
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• v.21 no.4
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• pp.91-98
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• 2019

In modern times, numerous cities are competing to create the unique skyline adjacent to the water. Tall buildings located across the river have a great contribution to the skyline of a riverfront city and can be a precious asset for the city. Moreover, in several cities, tall buildings and their impact on the urban skyline are a matter that should be considered and regulated in urban design. Therefore, as a prominent element in a larger visual setting of the city, tall buildings should improve the visual quality of the skyline rather than diminish that quality. This research attempts to provide an objective method to analyze the visual quality of the skyline made by a group of tall buildings through their feature of heights and spatial arrangement from riverfront views. The analysis is determined by the design variables of building heights variation, heights transition, density, and spacing of a group of tall buildings. A comparative case study of tall buildings in Yeouido and Lujiazui was conducted to prove the effectiveness of the analysis. The proposed method can be used in a simple way in the quantitative approach to quantify the visual quality of the skyline. In conclusion, Yeuido's skyline is not quite interesting from the riverfront view in terms of height variation and continuity of the skyline view because they are dispersed. Conversely, Lujiazui's skyline from the riverfront vantage points has a good quality in all aspects of the feature of height and spatial arrangements of tall buildings cluster. These factors can be used for the urban designer on how proposed tall buildings within the cluster should appropriately respond to adding image on the skyline.

• Journal of The Korean Society of Grassland and Forage Science
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• v.17 no.3
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• pp.205-212
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• 1997

Forty-five holstein calves (average liveweight 150kg) were used to investigate the effect of combination of tall fescue and white clover cultivars on liveweight gain and feed efficiency into animal product in pastures. Daily gains per head for 3 years in T1, T2 and T3 (TI : Fawn, tall fescue + Regal, white clover + orchardgrass + perennial ryegrass, T2 : Roa, tall fescue + Regal, white clover + orchardgrass + perennial ryegrass, T3 : Roa, tall fescue + Tahora, white clover + orchardgrass + perennial ryegrass) were 0.27, 0.37 and 0.35kg, respectively, while average daily weight gains per ha were 3.54, 4.47 and 4.43kg, respectively. Animals grazing on mixed pasture with Roa tall fescue and Regal or Tahora white clover were showed a higher liveweight gain than those grazed on pastures with Fawn tall fescue and Regal h i t e clover. There was no significant difference among treatments (TI = 5.0kg T2 = 4.8kg T3 = 4.9kg) in herbage intake but feed efficiency into animal product was showed higher in T2 and T3 in comparison with T1(7.9% in T2 and 8.0% in T3 vs 5.97% in TI). In conclusion, association with Roa tall fescue and Regal white clover in mixed pasture can obtain higher animal product under continuous grazing system than that with Fawn tall fescue and Regal white clover.

• Journal of The Korean Society of Grassland and Forage Science
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• v.18 no.2
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• pp.133-142
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• 1998

This study was conducted to investigate the effects of antagonistic bacteria and pathogenic fungi on the growth of tall fescue(Festuca arundinacea Schreb.) in continuous cropping soil(CCS) and non-continuous cropping soil(NCCS). Tall fescue was established by seeding into pots of 11 cm in diameter and 9 cm in depth containing 1 : 1 mixture of soil and vermiculite, and cultivated at pots with antagonistic bacteria and pathogenic fungi in a vinyl house. The bacteria used in this study were Bacillus subtilis and hsants. B. subtilis was isolated and identified kern forage rhizosphere soil and fusants were isolated through cell hsion from B. subtilis and B. thwingiensis. B. subtilis was named as B. subtilis 101 and hsants were named as F-3, F-7 and F-8. In dark culture experiment, tall fescue inoculated with the antagonistic bacteria lived longer than that of control in both CCS and NCCS. However, tall fescue of CCS lived shorter than that of NCCS. Dry weight of tall fescue inoculated with the antagonistic bacteria was higher than that of tall fescue inoculated with pathogenic hngi in both CCS and NCCS(P< 0.05), and the antagonistic bacteria showed positive effects on the growth of tall fescue. However, Dry weight of tall fescue was decreased by the inoculation of the pathogenic b g i in both CCS and NCCS(P< 0.05).

• Journal of The Korean Society of Grassland and Forage Science
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• v.26 no.4
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• pp.221-226
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• 2006

This study was conducted to investigate the effect of tall type mixtures and turf type mixtures on dry matter yield, botanical composition and quality. The experimental design includes two mixture types : Tall type mixtures; orchardgrass (Potomac) 50+tall fescue (Fawn) 20+ Kentucky bluegrass (Kenblue) 10+red clover (Kenland) 20%) and turf type mixtures; Kentucky bluegrass(Newport) 60%+tall fescue (reboil Jr.) 20+perennial ryegrass (palmer II) 20%. The DM yield was higher obtained in tall type mixture than that of turf type mixture (p<0.05). In the chemical composition, Turf type mixture was higher in crude protein (CP) and dry matter digestibility (DMD), but lower in fibrous compound as NDF, ADF, cellulose and lignin than those of tall type mixture (p<0.05). The crude protein dry matter (CPDM) and digestible dry matter (DDM) yield was higher in tall type mixture than turf type mixture (p<0.05). In this experiment, nutritive value of turf type mixture was higher than that of tall type mixture, but CPDM and DDM yield of turf type mixture were lower than that of turf type mixture due to low dry matter yield. On the other hand, turf type mixture was obtained high feed value, and maintaining the various botanical composition on the 13 th cutting frequency condition. therefore, turf type mixture had a utilization possibility under grazing livestock as sheep and milk goats.

• International Journal of High-Rise Buildings
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• v.4 no.4
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• pp.311-318
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• 2015

The ASHRAE Design Guide for Tall, Supertall and Megatall Building Systems was produced in collaboration with the CTBUH. The design guide outlines various tall building mechanical systems that are presently being designed or are planned for the future. Tall commercial buildings in particular present a series of design problems that set them apart from other functions. The Design Guide will be of interest to owners, architects, structural engineers, mechanical engineers, electrical engineers and other specialized engineers and consultants. This design guide addresses design issues for tall commercial buildings, which are very often mixed-use, and commonly consist of low level retail, office floors, residential units, and hotel uses.

• Wind and Structures
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• v.23 no.5
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• pp.385-403
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• 2016

The across-wind dynamic loads on L-shaped tall buildings with various geometric dimensions were investigated through a series of wind tunnel testing. The lift coefficients, power spectral densities and vertical correlation coefficients of the across-wind loads were analyzed and discussed in details. Taking the side ratio and terrain category as key variables, empirical formulas for estimating the across-wind dynamic loads on L-shaped tall buildings were proposed on the basis of the wind tunnel testing results. Comparisons between the predictions by the empirical formulas and the wind tunnel test results were made to verify the accuracy and applicability of the proposed formulas. Moreover, a simplified procedure to evaluate the across-wind dynamic loads on L-shaped tall buildings was derived from the proposed formulas. This study aims to provide a simple and reliable way for the estimation of across-wind dynamic loads on L-shaped tall buildings.

• Journal of The Korean Digital Architecture Interior Association
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• v.12 no.1
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• pp.109-118
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• 2012

The Purpose of this study is to develop a design process of free-formed super tall buildings with parametric design approach using BIM. Before BIM tools like Revit was developed, it is considered as very time consuming process and requires extensive efforts and costs for making free-formed super tall building modeling. Current trends of free-formed super tall building are for proofing city's economic strength and symbol. New digital tools have been developed and used for pursuing many design methods for building design. In this study, BIM based Parametric design approach is studied to seek for possibility of generating free-formed super tall building fast, easily, and accurately.

• KIEAE Journal
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• v.5 no.1
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• pp.11-18
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• 2005

The optimized HVAC system design in tall buildings enable owners to save unnecessary energy consumption and residents to have comfort environments. The purpose of this study is to develop design process for optimized HVAC system design in tall buildings. As basic researches, literature researches and case studies of HVAC system design in tall buildings were performed. Survey was processed among expert in the field and key considerations on HVAC system design were drew as conclusions. With these conclusions, studies were performed on effects of wind velocity, outdoor air temperature, and solar radiation that are main factors of load calculation in tall buildings. Finally, air-tightness and stack effect were analyzed and estimated by literature studies, field measurements and computer simulations.

• KIEAE Journal
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• v.10 no.3
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• pp.81-88
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• 2010

Current trend on sustainable tall building shows significant efforts on the integrated design approaches for the performative design to achieve efficient building for the energy, structural and materials. The design of tall buildings should take into consideration of environmental impact and economic benefits from sustainable approaches to ensure low energy consumption and CO2 emissions. Designing sustainable tall building require concerns and comprehensive understanding of sustainable building technology, sustainable rating system and supporting incentive policy. The research has been conducted on available rating system and the incentive policy for sustainable building design methodology through cases studies for this study. In the paper, author tried to emphasis the role of the incentive policy for the sustainable building and provides survey of the impact on rating, adaptable use of sustainable building technology on the current practice of tall building design.

• International Journal of High-Rise Buildings
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• v.3 no.3
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• pp.191-198
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• 2014

The tall building and super tall building has been a common building type in China, with multiple functions and complex geometry. Composite construction is broadly used in tall building structures and constitutes the mixed structure together with concrete and steel constructions. The mixture of the constructions is purposely designed for specific area based on the analysis results to achieve the best cost-effectiveness. New types of composite construction are conceived of by engineers for columns and walls. Material distribution is more flexible and innovative in the structural level and member level. However the reliability of computer model analysis should be verified carefully. Further researches in the design and build of composite construction are necessary to ensure the success of its application. Composite or Mixture Index is suggested to be used as a performance benchmark.