• Journal of The Korean Astronomical Society
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• v.44 no.3
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• pp.73-79
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• 2011

We collect 24 times of light maxima data from sources in the literature, unpublished data and open databases, and investigate the variations of the observed and calculated (O-C) values for light maxima of V1719 Cyg. We found no evidence of the variations in the (O-C) values. We estimate the effective temperature and surface gravity using both the Kurucz and MARCS/SSG grids for different metallicity values [A/H]=0.0 and +0.5 for V1719 Cyg. It is confirmed that the temperature is almost the same, but, in the case of surface gravity, the MARCS/SSG grid gives the value closest to that obtained from the period-gravity relation derived by using the pulsation-evolution theory. We obtain two spectra of V1719 Cyg from spectroscopic observation which permitted us to find the effective temperature and the surface gravity of the star directly. We estimate the metallicity and it is found that the abundance of iron is equal to the solar value.

• Proceedings of the KIEE Conference
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• 1995.07b
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• pp.506-508
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• 1995

The relay protection engineers are sometimes faced with the difficulties in full protection of high-inertia drive motors during acceleration period. The problem results from lower permitted locked rotor time of the motor compared with motor starting time. Even though the various types of protection relay and other device (Speed switch, Distance relay) are used, the full protections against abnormal starting conditions may not be available. So, the development of a new speed-biased overcurrent relay is suggested in this paper. This paper also presents that speed-biased overcurrent relay can fully protect the high-inertia motor during abnormal starting condition by computer simulation.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.11 no.17
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• pp.47-54
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• 1988

Korean National Railroad(K.N.R) playing a important role in land transportation gives us many problems to solve considering proper management of National Budget and development of the state of operation by maintaining train parts rationally as public services. According this study is to show inventory provision system for deciding the safety inventory level as the better rational method. Bibliography for this study is limited to only three kinds of seven brakes-shoe which is produced by T workshop in Korean National Railroad. To reduce the holding cost coming from the want of the stock and shortage cost of the stock expected. This study is to present a ratio of shortage on the stock permitted for the last definite period and the demand result forecast per month.

• International Journal of Advanced Culture Technology
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• v.8 no.4
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• pp.110-118
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• 2020

It is important to have an appropriate amount of inventory for effective operations. This study seeks to develop a sustainable newsvendor model by incorporating environment-related costs into the existing well-known (single-period) newsvendor model. Since leftovers do more harm to environments than stockouts, the optimal order amount tends to be lower than the traditional quantity. However, this is not the case when a second buy is allowed. A second order opportunity is prevalent in industries where it improves demand forecast despite incurring extra costs. In this study, we conduct an extensive numerical analysis for a newsvendor situation with a permitted second buy. The results show that we can reduce inventory costs by considering sustainability concerns. The research idea of including sustainability considerations into existing inventory models can be extended to a more general case and provides managerial insights for better inventory decisions.

• Journal of architectural history
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• v.3 no.2 s.6
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• pp.142-156
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• 1994

This paper aims to study on the periodical competition, the program, the jury organization, the reward, and copyright applied to the buildings which were constructed with architectural design competition performed in European and American region between 19c and 20c. The results of this study are as follows; 1. Befor 1900 Period, the type of buildings added to the competition program; between 1900 period and 1950 period, the works of strong nationality and rich local color were preferred; After 1950 period, the design drawings of high symbol and function were chosen 2. There are three types of design competitions: the open design competition, the invited and limited design competition, and the idea design competition. The open design competition has been most often made. 3. The juries were, most of all, composed of professional architects over 30 percent. 4. The program was written about building scale and appointments, described what form drawings, brief notes and air perspective wood have to be submitted. For instance, the use of colour was not permitted in the drawings, as this might possibly mislead the jurors. 5. The reward was given to the winners; the copyright was given to the first prize winner. 6. The standard of entry's qualification was mostly architect 7, Entry term was from a minimum month to a maximum year after annoncement of competition, it was approximetly 63% between 4 months and 8 months. I am convinced that architect gets freedom of pure creation and joy of society service through competition, architect justifies his profession and keep his useful and creative effort to society constantly, as long as the competition exists.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.36 no.3
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• pp.121-128
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• 2020

In this paper, the ASCE 7 equivalent static approach for seismic design of non-structural elements is critically evaluated based on the measured floor acceleration data, theory of structural dynamics, and linear/nonlinear dynamic analysis of three-dimensional building models. The analysis of this study on the up-to-date database of the instrumented buildings in California clearly reveals that the measured database does not well corroborate the magnitude and the profile of the floor acceleration as proposed by ASCE 7. The basic flaws in the equivalent static approach are illustrated using elementary structural dynamics. Based on the linear and nonlinear dynamic analyses of three-dimensional case study buildings, it is shown that the magnitude and distribution of the PFA (peak floor acceleration) can significantly be affected by the supporting structural characteristics such as fundamental period, higher modes, structural nonlinearity, and torsional irregularity. In general, the equivalent static approach yields more conservative acceleration demand as building period becomes longer, and the PFA distribution in long-period buildings tend to become constant along the building height due to the higher mode effect. Structural nonlinearity was generally shown to reduce floor acceleration because of its period-lengthening effect. Torsional floor amplification as high as 250% was observed in the building model of significant torsional irregularity, indicating the need for inclusion of the torsional amplification to the equivalent static approach when building torsion is severe. All these results lead to the conclusion that, if permitted, dynamic methods which can account for supporting structural characteristics, should be preferred for rational seismic design of non-structural elements.

• Computational Structural Engineering
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• v.9 no.4
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• pp.229-237
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• 1996

In some current procedures, ground motions from different sources have been scaled by their peak ground accelerations and combined to obtain smoothed response spectra for specific regions. As consideration of the inelastic deformation capacity of structure, inelastic deformations are permitted under seismic ground excitation in all codes. In the ATC(Applied Technology Council) and UBC(Uniform Building Code), the inelastic design spectrum is obtained by reducing the elastic design spectrum by a factor that is independent of structural period. In this study, the average of nonlinear response spectra calculated from a sample of 20 records for each event are constructed to obtain the smoothed response spectra. These response spectra are used to examine the effects of structural strength factors such as the yield strength ratio and damping value. Through the regression analysis of nonlinear response of system for a given damping value and yield strength ratio, the required yield strength for seismic design can be estimated for a certain earthquake event. And a response modification coefficient depending on the natural period for current seismic design specifications are proposed.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.7
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• pp.1610-1618
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• 2014

Wearable computer systems can use the wireless universal serial bus (WUSB) that refers to USB technology that is merged with WiMedia PHY/MAC technical specifications. In this paper, we focus on an integrated system of the wireless USB over the IEEE 802.15.6 wireless body area networks (WBAN) for wireless wearable computer systems supporting U-health services. And a communication structure that performs the hibernation for low power consumption is proposed for WUSB over IEEE 802.15.6 hierarchical protocol. In the proposed hibernation mechanisms, WUSB communications are permitted at each m-periodic inactive periods of WBAN superframes by using the WBAN information of Wakeup Period and Wakeup Phase message fields. In our performance evaluations, performances according to amount of WUSB traffic and Wakeup Periods are analyzed respectively to evaluate the effectiveness of proposed hibernation structure in WUSB over IEEE 802.15.6.

• Journal of the Korean Society of Food Culture
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• v.35 no.6
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• pp.613-618
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• 2020

This study evaluated the effects of acidulant treatment on the quality and storage period of Topokkidduck. Two samples of Topokkidduck were prepared, one soaked in 10% acidulant (10SAT) and the other without soaking in the acidulant (NSAT). During the storage period, the two samples were tested for presence of microorganisms (aerobic bacteria, E.coli, and mold) and physicochemical properties (color value, texture profile analysis (TPA)). The 10SAT could be stored for 49 days without detection of E.coli and a mold level of 1.0 log CFU/g. NSAT could be stored for only 21 days. NSAT had an aerobic count of 2.27 log CFU/g as early as 7 days, and E.coli was detected at 21 days at a level of 4.15 log CFU/g. The presence of E.coli is not permitted according to the Ministry of Food and Drug Safety (MFDS). The hardness of the 10SAT increased during the storage period but to a much lesser extent compared to the NSAT. Thus the preparation of Topokkidduck by soaking in the acidulant controlled microbial growth for up to 49 days which is a much longer period compared to the control. Also, Topokkidduck soaked in the acidulant had a softer texture than the control during the storage period.

• Journal of the Korean Society of Earth Science Education
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• v.8 no.3
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• pp.355-366
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• 2015

The purpose of this study was to investigate the elementary school pre-service teachers' and in-service teachers' and STEAM leader school teachers' difficulties and requirements in the relation to STEAM Education. For this study, 49 pre-service teachers, 57 in-service teachers, 16 leader school teachers in G Area were selected. And they conducted the survey. The results of this study were as follows. First, in order to minimize elementary teachers' physical burden actually, it is necessary to distribute STEAM teaching materials including various and specific programs to the schools in the booklet. Second, for the fast and effective spreading of STEAM, it also should be permitted the pre-service teachers to access STEAM homepage, which is limited to teachers. Third, we should make circumstance to research on STEAM through collaboration with colleagues freely. Therefore, we should give intensive training and consulting opportunities to science teacher. Because they who is getting stronger in this field to do this can furnish other colleagues to teaching tips and information in the relation to STEAM education. By all this fulfillment simultaneously, STEAM will be settlement in elementary school in the short period.