• The Journal of the Convergence on Culture Technology
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• v.9 no.2
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• pp.57-65
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• 2023

This study examined the obstacles of important factors involved in the start-up decision process for prospective entrepreneurs and plans after graduation while attending hair and beauty colleges and analyzed them in a phenomenological way to establish countermeasures. The subjects of the study agreed to collect data from 10 prospective entrepreneur doctors and plans after graduation while attending hair and beauty college located in G, and were in-depth from December 15 to December 30, 2022. The collected data were analyzed using the Colaizzi method. The results of this study were extracted with 13 topics and two subject collections that represent the characteristics of the experience in the preliminary start-up process of the participants. Based on the results of this study, it is meaningful to examine the obstacles of the factors that are importantly involved in the start-up decision process and establish countermeasures accordingly. In conclusion, at a time when the market for start-ups is expanding and government support is increasing, the factors affecting the will of college students, who are potential professional managers in the future, and effective implications for enhancing the university's start-up infrastructure, start-up difficulties, and start-up motivation were obtained. Therefore, it is urgent to develop efficient performance counseling research or program counseling that can promote and support mental and environmental growth through career development required for the difficulties of the decision process of prospective entrepreneur hair college students and the situations they face. It is necessary to develop various measurement tools in consideration of the level of career development and development of a start-up decision-making process model that can fully grasp the status of start-ups of prospective start-ups.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.35 no.12
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• pp.594-602
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• 1986

This paper proposes an effective algorithm for short-term generation scheduling for the purpose of economic and secure operation of thermal power systems. Especially, in the procedure of solution by Dynamic Programming, Linear Programming is introduced to promote the possibility of optimal solution and the security of power systems, and evaluation of security function is improved by the application of seven step approximation of normal distribution. Several necessary considerations, that is, time dependent start-up and constant down cost of generating units, demand and spinning reserve constraints, minimum up and sown time constraints, the number of possible start-up of a generating unit in a d and the number of generating units which can be started up at the same time at the same bus, are also incoporated to elevate the usability and flexibility of the algorithm. Finally, the effectiveness of the proposed algorithm has been demonstrated by applying to the 6-gen. 21-bus model power system.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 1996.11a
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• pp.49-52
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• 1996

This paper reports the development of an electronic starter for fluorescent lamps, which is so smartly designed that can be used directly in existing installations. The key point of the design lies in the protection of lamp filaments by sufficient preheating and at the same time in the control of time constant for start-up circuit. The starter is consisted of three system parts: a rectifier pact, a switching part. and a gate control part. The characteristics of the developed electronic starter is compared with those of a conventional glow starter. As a result, blackening of lamps is almost reduced due to the stable and idealized start-up characteristics. And, furthermore, it is shown that its slaving time is shortened at about half the level of the conventional one and the starting power is also reduced.

• Journal of the Korean Society of Industry Convergence
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• v.9 no.3
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• pp.191-197
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• 2006

Prepare need in each branch for a large scale event. especially prepare for transportation problem is very important. most research for until at now parking prepare according city management however, parking prepare for large event is a necessity which it will parking characteristic. accordingly this research is conducted study for parking prepare subject of large event. this study result, vehicle demand for parking by stadium have many but vehicle demand for parking off stadium have few. accordingly large parking supply is ineffective. shuttle bus service in principal position of city is effective. study result showed that it included 85% parking at 6~7hour before large event start time. accordingly disposition time of parking manager is desirable 6~7hour before large event start time.

• ETRI Journal
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• v.45 no.2
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• pp.226-239
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• 2023

Challenges in cognitive radio and tactical communications include recognizing anonymously received signals and estimating parameters in a blind or semi-blind manner. In this paper, we examine this issue for orthogonal frequency division multiplexing (OFDM) signaling. There are several parameters in OFDM signaling, and the blind receiver must extract and consider the synchronization issue. We assume that the blind receiver is aware of modulation type, OFDM, and not aware of chip duration and the length of cyclic prefix. First, we present new criteria based on kurtosis to estimate these parameters and compare their performance at different levels of additive white Gaussian noise with methods based on correlation, kurtosis, maximum likelihood, and matched filter. Then, we perform synchronization and estimate the start time based on these criteria and several new criteria in two steps: fine and coarse synchronization. Finally, in a more practical setup, we present the idea of jointly estimating the mentioned parameters and the signal start time as coarse synchronization. We compare different criteria and show that one of the proposed criteria has the highest efficiency.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.10a
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• pp.520-521
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• 2017

The converted error is occurred by the time difference between the time interval signal and the clock in a Time-to-Digital Converter of counter-type. If the clock period is $T_{CLOCK}$ the converted error is a maximum $T_{CLOCK}$ by the time difference between the start signal and the clock. And the converted error is a maximum $-T_{CLOCK}$ by the time difference between the stop signal and the clock. However, when the clock is synchronized with the start signal and the colck is generated during the time interval signal the range of converted digital error is from 0 to $(1/2)T_{CLOCK}$.

• Nuclear Engineering and Technology
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• v.56 no.1
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• pp.56-63
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• 2024

In high radiation fields, gamma cameras suffer from pulse pile-up, resulting in poor energy resolution, count losses, and image distortion. To overcome this problem, various methods have been introduced to reduce the size of the aperture or pixel, reject the pile-up events, and correct the pile-up events, but these technologies have limitations in terms of mechanical design and real-time processing. The purpose of this study is to develop a real-time gamma camera to evaluate the radioactive contamination in high radiation fields. The gamma camera is composed of a pinhole collimator, NaI(Tl) scintillator, position sensitive photomultiplier (PSPMT), signal processing board, and data acquisition (DAQ). The pulse pile-up is corrected in real-time with a field programmable gate array (FPGA) using the start time correction (STC) method. The STC method corrects the amplitude of the pile-up event by correcting the time at the start point of the pile-up event. The performance of the gamma camera was evaluated using a high dose rate ¹³⁷Cs source. For pulse pile-up ratios (PPRs) of 0.45 and 0.30, the energy resolution improved by 61.5 and 20.3%, respectively. In addition, the image artifacts in the ¹³⁷Cs radioisotope image due to pile-up were reduced.

• Plant Journal
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• v.10 no.1
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• pp.47-53
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• 2014

The national capacity of electricity of Korea was 81,737 MW and the peak demand was renewed by the record of 71,230 MW in 2012 which has been increasing since the first lighting ceremony had taken place in the Royal Palace(Kyung-Bok Goong) in 1887. Aa the counteract on the rapid increasing of the demand, Korean government is constructing and operating the high capacity nuclear and thermal power plants, however, the operating reserve on weekdays is small while those of weekends are more than 40% of capacity, so they are providing the pumped-storage power plants with the surplus electricity during weekends and operating the power plants which cost higher production price and located in the capital area with WSS (Weekly Start and Stop) mode including the Seoul Thermal Power Plant. Since the Seoul Thermal Power Plant is spending huge amount of expenses for more than 30 times of the WSS annually due to the high production cost even though it is in Seoul, the core of the demand, I chose the power plant unit #5 which was on the grid in 1969 for the case to confirm reducing 23% of the warm start-up time by applying the "Start-up time management program", and that reducing 35% of the water temperature increasing time by accelerate the increasing rate of the inlet temperature of the water circulating pump.

• Fire Science and Engineering
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• v.26 no.2
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• pp.59-68
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• 2012

Predicting occupants' behaviors from the start of the fire to egress and reducing the time required for such process are critical matters that can decide success and failure of safe egress. In this research, research literatures and theories and fire cases were compared and analyzed so as to prepare logical grounds that could predict the process of beginning egress. As a result of this research, there was a significant difference in the time elapsed until people start evacuating due to spatial positions and quarantine from the place from which the fire originated and their auditive and olfactory signs did not recognize the fire instantly and they showed a strong tendency to recognize the fire by visual sign, warning announcement for egress and notice by others. And the results also showed that only a very small minority of occupants evacuated as soon as they perceived the fire and that variation in the time elapsed until evacuation begun for occupants were wider as the size of building was bigger and that accommodations such as hotel had wider variation in the time elapsed regardless of the size of buildings.

• Journal of Korean Institute of Industrial Engineers
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• v.25 no.1
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• pp.141-149
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• 1999

In this paper, we consider multiple-class queueing systems in which the server starts a set-up as soon as the number of customers in the "start-up class" reaches threshold N. After the set-up the server starts his service. We obtain the Laplace-Stieltjes transform and the mean of the waiting times of each class of customers for FCFS and non-preemptive priority disciplines.