• International Journal of Concrete Structures and Materials
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• v.5 no.2
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• pp.113-117
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• 2011

The purpose of this work is the comparative study for grinding of two cement clinkers. X-ray fluorescence, physical and granulometric tests and optical microscopy were used to characterize the clinkers. Also grinding tests were carried out for ten samples to determine the parameters influencing grindability of its clinkers. The results of calculation of the energies of grinding according to the law developed by Von Rittinger and the study of the microstructure of the two clinkers shows good agreements. Indeed, frequent clusters of belite which indicate a lack of uniformity and fineness have an effect on lowering the grindability. The obtained analyses and the results enabled us to interpret the granulometry and the microstructure of clinker to control quality and resistance.

• International Journal of Aeronautical and Space Sciences
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• v.18 no.2
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• pp.222-235
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• 2017

In this study, finite element modeling was used to predict the material properties of tri-axially braided textile composite. The model was made based on an experimental test specimen which was also used to compare the final results. The full interlacing of tows was geometrically modelled, from which repeating parts that make up the whole braid called unit cells were identified based on the geometric and mechanical property periodicity. In order to simulate the repeating nature of the unit cell, periodic boundary conditions were applied. For validation of the method, a reference model was analyzed for which a very good agreement was obtained. Material property calculation was done by simulating uniaxial and pure shear tests on the unit cell. The comparison of these results with that of experimental test results showed an excellent agreement. Finally, parametric study on the effect of number of plies, stacking type (symmetric/anti-symmetric) and stacking phase shift was conducted.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.11 no.4
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• pp.542-548
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• 1999

Instead of testing split air conditioners, an empirically based calculation procedure may be used to estimate the Energy Efficiency Ratio at ARI A test conditions. Typically, the system involving the indoor unit well sold and the given outdoor unit is called the matched system. All other systems involving a given outdoor unit and other indoor units are called the mixed systems. To estimate the EER(A) for the mixed systems, EER(A) for the matched system must be known, Generally, the EER(A) for the matched system is known. This procedure relies on independent measurements and calculations made on an outdoor unit in conjunction with a matched indoor and a mixed indoor coil. A heat pump simulation model was used to quantify the effects of individual system components on the system performance. The procedure is applicable to all air-conditioning units having rated cooling capacities less than 19,000W and charged with refrigerant 22.

• Nuclear Engineering and Technology
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• v.29 no.5
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• pp.375-384
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• 1997

Relative power density distributions of the Kori Unit 1 pressurized water reactor are calculated by Monte Carlo modeling with the MCNP code. The Kori Unit 1 core is modeled on a three-dimensional representation of the one-eighth of the reactor in-vessel component with reflective boundaries at 0 and 45 degrees. The axial core model is based on half core symmetry and is divided into four axial segments. Fission reaction density in each rod is calculated by following 100 cycles with 5,000 test neutrons in each cycle after starling with a localized neutron source and ten noncontributing settle cycles. Relative assembly power distributions are calculated from fission reaction densities of rods in assembly. After 100 cycle calculations, the system converges to a k value of 1.00039 $\geq$ 0.00084. Relative assembly power distribution is nearly the same with that of the Kori Unit 1 FSAR. Applicability of the full-scope Monte Carlo simulation in the power distribution calculation is examined by the relative root moan square error of 2.159%.

• Proceedings of the Korean Biophysical Society Conference
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• 1996.07a
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• pp.10-10
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• 1996

High-resolution solution conformation of a novel conotoxin, [Pro 7,13] $\alpha$A-conotoxin $P_{IVA}$, GCCGSYPNAACHPCSCKDROSYCGQ-N $H_2$, has been determined by two-dimensional $^1$H nmr methods in combination with distance geometry calculation to rmsd values of 0.90 $\AA$ and 1.16 $\AA$ for the backbone and heavy atoms, respectively. Total of 324 NOE-derived interproton distance restraints including 33 long-range NOE restraints a well as 11 $\Phi$ and 7 $\chi$$^1$ torsion angle restraints were used for computation of structures. (omitted)d)

• Journal of The Korea Institute of Healthcare Architecture
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• v.19 no.1
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• pp.59-66
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• 2013

Purpose: Although Computerized Tomography is one of the most useful diagnosis devices and Frequency of use by all kind of patient is higher than other device, it can be hardly to find out adequate data to planning of Computerized Tomography Unit. So questions have been raised about how to organize the unit. Methods: In order to suggest architectural guideline of Computerized Tomography Unit, expert interview, field survey and analysis to the floor plan have been conducted in this article. The area calculation was based on center line. Results: This article suggests a number of the guideline and the example of the planning which contains how to design Computerized Tomography Unit. Especially, in the case of the example on the planning, main points of the guideline is reflected. Implications: The result of this survey would be useful as a reference when the architect tries to design Computerized Tomography unit.

• Journal of Aerospace System Engineering
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• v.12 no.5
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• pp.48-53
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• 2018

In this study, Real-Time Operating System(RTOS) and 3-D collision avoidance algorithm are implemented to three different Miciro Controller Unit(MCU)s and their performances compared. We selected Microchip Technology's ATmega2560, STM's ARM Cortex-M3 and ARM Cortex-M4, because they are widely used. FreeRTOS, an open-source operating system, was also used. The 3D collision avoidance algorithm consists of the vertical and the horizontal avoidance algorithm, which is implemented using C++. The performances of the MCUs were compared with respect to used memory and calculation time. As a result, Cortex-M4's calculation time was the fastest and ATmega2560 used least memory.

• Journal of the Korea Safety Management & Science
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• v.15 no.3
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• pp.113-125
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• 2013

According to 2012 OECD environmental report, Korea was ranked as the first country of water stress. Water footprint is a method to calculate water usage during the life cycle of a product from material procurement through production to disposal to recycle and to quantify the load to water resources. In water footprint calculation, water consumption unit is used. Agricultural water use is over 48% so it is urgent to mange that area Korea needs to spread the discussion about water footprint as quickly as possible, for the study to prevent social and environmental problems due to water shortage. This paper, through water footprint calculation and comparison in Chungju and Geochang areas, looks to counter measures for water risk, targeting domestically-produced apple.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.2353-2355
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• 2010

Since the efforts in transportation for counteracting Climate Change have been enhanced, it is necessary to reduce GHG emissions from railroad construction. The aim of this study was to develop the calculation method of GHG emissions at the step of railroad construction. Main emission source was the energy consumption from the used heavy equipments. Firstly, GHG inventory including equipments list, energy consumption, and work load was established with the detailed process using standard for the unit cost of construction. Also, the energy consumption of heavy equipments during track construction at A site was collected to compare with the field data. As a result, the GHG emissions between the estimated and the field were a little different, which was caused by the inaccurate field data. Therefore, it is important to manage data efficiently for the calculation of GHG emissions in the field of railroad construction.

• Proceedings of the KIEE Conference
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• 1999.07e
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• pp.2047-2050
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• 1999

This paper presents some of the results of current research on 300 kN Suspension Insulator Design. In this paper, authors first used 2-dimensional field calculation to solve the electric field distribution of an insulator unit and insulator strings, and then 3-dimensional field calculation in order to overcome the shortcomings of 2-dimensional field calculation in which an axis-symmetrical coordinate has been used. And, it was found that the environmental configuration of 300 kN Suspension Insulator String gives great roles to the field distribution of the insulators.