• Journal of the Korean Society of Industry Convergence
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• v.22 no.6
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• pp.711-719
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• 2019

At present, wind power is the fastest growing technology in the world. The domestic market depends heavily on imports for wind tower lift. so it manage through the overseas maker. The lift manufacture, establishment and maintenance utility is increasing, localization development of one wind tower lift is necessary with domestic fundamental base technique. In this paper, we will study the components necessary for the development of onshore offshore wind tower elevators, which are currently dependent on total imports, in line with the high growth of the wind market and the enlargement of the wind power generators. First of all, endless winders and cabins, which are the core components of the offshore wind tower lift, were examined for the components that affect the structural safety. Structural analysis was performed on Sheave, which is responsible for most of the lift lifting loads, and Block Stop, a safety device that prevents the cabin from falling in an emergency. The structural suitability was evaluated by comparing with the safety factor. In addition, the on-board control panel combines the control panel of the elevator and the drive motor driving the endless winder for efficient control of the offshore wind tower lift. The addition of features improves ride comfort at departure.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2004.11a
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• pp.174-181
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• 2004

We will introduce a method of construction of super-block curtain wall applied to Tower Palace III which is the highest high-rise complex building in Korea. Up-up method is utilized on Tower Palace III to shorten the term of works and it is that the curtain walls for the belt wall part are installed after the rests. The belt wall structure increases the horizontal structural stiffness of the building. The method of construction of super-block curtain wall is developed and used to raise and install the curtain wails of the belt wall floor. It is that the large block of curtain walls corresponding to three stories is fabricated on the ground in advance and the block is installed at a time by a tower crane. Specialized installing equipment :,s newly developed and applied to install the super-block. curtain wail. The curtain wall of the upper floor of the belt wall part is installed after the super-block. The installing equipment for this floor is developed utilizing a mini excavator and vacuum suctions. The application of this method had made it possible to omit the setting up the scaffold and financial profits such as the shortening of the terms of works was realized. The safety of works was secured and the productivity was also improved.

• Advances in Energy Research
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• v.4 no.1
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• pp.29-45
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• 2016

There has been a growing interest in the recent time for the development of solar power tower plants, which are mainly used for utility scale power generation. Combined heat and power (CHP) is an efficient and clean approach to generate electric power and useful thermal energy from a single heat source. The waste heat from the topping Brayton cycle is utilized in the bottoming HRSG cycle for driving steam turbine and also to produce process steam so that efficiency of the cycle is increased. A thermal storage system is likely to add greater reliability to such plants, providing power even during non-peak sunshine hours. This paper presents a conceptual configuration of a solar power tower combined heat and power plant with a topping air Brayton cycle. A simple downstream Rankine cycle with a heat recovery steam generator (HRSG) and a process heater have been considered for integration with the solar Brayton cycle. The conventional GT combustion chamber is replaced with a solar receiver. The combined cycle has been analyzed using energy as well as exergy methods for a range of pressure ratio across the GT block. From the thermodynamic analysis, it is found that such an integrated system would give a maximum total power (2.37 MW) at a much lower pressure ratio (5) with an overall efficiency exceeding 27%. The solar receiver and heliostats are the main components responsible for exergy destruction. However, exergetic performance of the components is found to improve at higher pressure ratio of the GT block.

• Journal of Korean Society on Water Environment
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• v.31 no.6
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• pp.637-643
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• 2015

This study has been carried out to provide the basic data obtained from the evaluation of the variation of water quality around the Chudong intake tower in Daechung resevoir, which may be able to help the establishment of a pure water supply policy. Five sites around the Chudong intake tower were selected, and the average data for recent ten years(from year 2004 to year 2013) were analysed. The average water quality around Chudong intake tower are as followed; pH 7.5, DO 8.7 mg/L, BOD 1.0 mg/L, COD 3.0 mg/L, SS 3.0 mg/L, TN 1.495 mg/L, TP 0.017 mg/L, and Chlorophyll-a 6.5 mg/m³ were matched the good class by comparing with the living environment standard of reservoir. COD values of higher than 3.0 mg/L after July were likely due to non-point pollutants and algae outbreak during rainy summer season. Total phosphorus rose sharply in the summer season, and then algae watch was issued consistently for average 40 days. Total nitrogen to total phosphorus ratio was average 90, and it is important to control the inflow phosphrous from small stream for proper management to block an algae growth according to eutrophication. It was recommended to operate the algae removing boats around intake tower from July to October, and was required advanced water treatment processes to remove NBD COD and bad odor and taste due to algae growth.

• Steel and Composite Structures
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• v.1 no.2
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• pp.159-170
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• 2001

The Millennium Tower is situated to the north of the center of Vienna. With a height of 202 m it is the highest building in Austria. Realization was improved by new methods. The tower is a typical example of mixed building technology, combining composite frames with a concrete core. Special attention has been paid to the moment connections between the slim floors and the column tubes resulting in a drastically reduced construction time and thin slabs. The semi-continuity has been considered in the design at ultimate and serviceability limit states.

• Structural Engineering and Mechanics
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• v.8 no.5
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• pp.491-504
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• 1999

The initiation of toppling is explored for a uniform stack of blocks that rotates slowly about its mid-base. As the stack passes through its vertical position ($\theta$=0), it is in free-fall rotation, and a critical inclination angle ${\theta}_c$ is reached at which the toppling stack "fails" or begins to crack or separate. For tall stacks (high aspect ratios), two modes of failure are hypothesized, for which the dynamic failure analyses are shown to correlate with experimental results. These block failure modes are similar to those observed for tall, toppling masonry structures with weak binding material between their brick or stone blocks.

• Journal of the Korean housing association
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• v.24 no.3
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• pp.9-18
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• 2013

This paper aims to investigate the design characteristics of a single housing block which is increasing in urban areas. For the analysis, all cases of single block housing in Daejeon metropolitan city were gathered into a database. Main concerns were on the location and the physical characteristics. The results of this study were as follows; 1) single block housing has been increasing both in the new developed areas and the existing urban areas 2) their location has shifted from residential districts to semi-residential and commercial districts. For this reason, the size and density has been increasing 3) the slab block with the hall type and the exterior corridor type were general in residential districts, diverse ones, however, including the point tower type were increasing with unusual circulation types such as central corridor, central core, double corridor, and mixed type in semi-residential and commercial districts 4) there were 5 types of access systems, and especially the street access and the piloti access were increasing, which were related with the high density.

• Proceedings of the KIEE Conference
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• 1987.07a
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• pp.185-189
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• 1987

An analysis and design of large-scale linear multivariable systems often requires to be block triangularized form for good sensitivity of the systems when their poles and zeros are varied. But the decomposition algorithms presented up to now need a procedure of permutation, rescaling and a solution of nonlinear algebraic equations, which are usually burden. To avoid these problem, in this paper we develop a newly alternative block triangular decomposition algorithm which used the generalized matrix sign function on the Z-plane. Also, the decomposition algorithm demonstrated using the fifth order linear model of a distillation tower system.

• Journal of the Earthquake Engineering Society of Korea
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• v.23 no.1
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• pp.19-29
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• 2019

Recent earthquakes in Korea caused some damages to stone pagodas and thereby awakened the importance of earthquake preparedness. Korean stone pagodas which have been built with very creative style of material use and construction method are worthy of world heritage. Each stone pagoda consists of three parts: top; body; and base. However each tower is uniquely defined by its own features, which makes it more difficult to generalize the seismic assessment method for stone pagodas. This study has focused on qualitative preliminary evaluation of stone pagodas that enables us to compare the relative seismic performance across major aspects among many various Korean pagodas. Specifically an analytical model for multi-block stone pagodas is to be proposed upon the investigation of structural characteristics of stone pagoda and their dynamic behavior. A strategy for seismic evaluation of heritage stone pagodas is to be established and major evaluation factors appropriate for the qualitative evaluation are identified. The evaluation factors for overall seismic resisting behavior of stone pagodas are selected based on the dynamic motions of a rigid block and its limit state. Numerical simulation analysis using discrete element method is performed to analyze the sensitivity of each factor to earthquake and discuss some effects on seismic performance.

• Journal of the Korean Institute of Rural Architecture
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• v.20 no.2
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• pp.11-18
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• 2018

The purpose of this study is to analyze the structure and use change of the private space according to the balcony expansion and use it as the data of plan design. According to Bay, front length/width ratio and the change of balcony space before and after expansion of space organization of house units were analyzed. Common characteristics of Flat type and Tower type are an increase of the frontage length of house units in an apartment, an increase of the number of front bay, and an increase of integrated LDK focusing on living room. A difference is that Flat type shows high frontage ratio, Bay figure, and spatial arrangement favorable to front openness and lighting. Flat type shows higher area distribution than Tower type in LDK area distribution located in at the plane center. Spatial expandability and visual openness of Flat type are more beneficial than those of Tower type in the planning, and a balcony extension of house units has developed to direction to open more. Tower type creates various block images through a combination of house units focusing on the core. Uses after balcony expansion are area expansion of a balcony-neighboring room, storage space, expansion and function improvement of the variable range, and specialized space different from a neighboring room. In addition, there is no escapable space except for a shelter, so unit plan should be prepared to prevent using it other space of a shelter and to solve moving line of two-way horizontal refuge and vertical refuge.