• Journal of Korean Society of Transportation
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• v.34 no.5
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• pp.421-436
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• 2016

Public-Private-Partnerships tend to be committed high project development cost and recover the cost through future revenue during the operation period. In general, long-term concession can bring on more revenue to private investors, but short-term concession less revenue due to the short recovering opportunities. The concession period is usually determined by government in advance or by the private sectors's proposal although it is a very crucial factor for the PPPs. Accurate traffic forecasting should be most important in planing and evaluating the operation period in that the forecasted traffic determines the project revenue with user fees in PPPs. In this regards, governments and the private investors are required to consider the traffic forecast risk when determining concession period. This study proposed a model for the optimal concession period in the PPPs transportation projects. Monte Carlo simulation was performed to find out the optimal concession period while traffic forecast uncertainty is considered as a project risk under the expected return of the private sector. The simulation results showed that the optimal concession periods are 17 years and 21 years at 5.5% and 7% discount level, respectively. This study result can be applied for the private investors and/or any other concerned decision makers for PPPs projects to set up a more resonable concession period.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.5
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• pp.350-355
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• 2013

Little information is available for emission pathway even if HFC-134a that is known as one of the major greenhouse gases has been broadly used in Korea. This paper attempts to clarify the emission characteristics of HFC-134a used for refrigerant of cold drinking vending machines (CDVMs) at the use- and disposal-phase. We measured the residual amounts in the scrap CDVMs of 47 by applying commercial recover for refrigerant. The first-order kinetic model was introduced and the emission rate would be proportional to the remaining quantity of refrigerant. The emission factor at the use-phase was determined indirectly to be $6.9{\pm}0.7$ %/yr within a confidence interval of 95%, using information on residual amount and elapsed operation time at the disposal point. Correspondingly, the annual emission rate of HFC-134a per CDVM was determined to be 11.6 g. The average residual rate of HFC-134a in scrap CDVMs was assessed to be $62.5{\pm}2.2%$, leading to a potential emission amount of 144.8 g per scrap CDVM. The chemical compositions of refrigerants from scrap passenger vehicles are quite similar to those of new refrigerants, suggesting that the refrigerants from scrap passenger vehicles could be reused. During the recovering process of refrigerant, the recovered refrigerant was contaminated by compressor lubricant that accounted for about 30% in weight. It is necessary to separate the refrigerant from the recovered material contaminated by lubricant for recycling and reuse the refrigerant.

• The Journal of the Korea Contents Association
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• v.18 no.4
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• pp.636-652
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• 2018

This study is about applying the concept of moral injury in reinterpreting and understanding the experience of female North Korean refugees who have experienced psychological trauma and are struggling with adjusting in their everyday lives. The database KISS and DBpia were used to search for academic peer-reviewed articles published before August 13th in 2017, using 'female or women North Korean,' 'female or women relocated North Korean,' and 'female or women North Korean defector' as keywords. In total 51 studies were finally selected for content analysis and the result were the following. First, listing from the most often occurring study topic to the least occurring topic in order: post-defection adjustment related, mothering experience, experience of North Korean regime and Korean War, work or job or employment related, recovering from psychological trauma as well as growth and resilience related, experiences in China, trauma and psychological difficulties, anxiety treatment process and effects. Second, words related to psychological aspect of moral injury appeared 260 times in 51 selected studies, changes in the existential belief appeared 82 times, cognitive aspects of moral injury appeared 71 times, and behavioral aspects 21 times. Third, two main contexts emerged to be the antecedent that led to moral injury and they were 'identity denial' and 'dismantled family.' In attempts to find opposite cases or stories where aspects of moral injury were not found despite the existence of its antecedents and it was 'identity restructuring.' Based on the finding, practice implications that could help female North Korean refugees prevent or recover from moral injury were suggested.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.12
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• pp.7324-7330
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• 2014

Color distortion of the dark images acquired under a low-light-level environment with a weak light source can be cause of the performance decreation of various vision systems. Therefore, recovering the original color of the images is an important process for enhancing the performance of the system. For this, this study proposes a color restoration method using a dichromatic reflection model. This paper assumes that the dark images can be classified into two parts affected by specular or diffuse reflection. Two different color constancy methods were then applied to the images to remove the effects of each reflection and two images were created as a result. The resulting images produced a one color-corrected image by combining with different weights according to the position in the images. For the performance evaluation, this paper used a synthesized image, and considered the Euclidean distance and angular error as an evaluation factor. In addition, a performance comparison was performed with the existing various color constancy method to achieve the objectivity of evaluation. The experimental results showed that the proposed method can be a more suitable solution for color restoration than the existing method.

• Resources Recycling
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• v.22 no.2
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• pp.22-28
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• 2013

In the present study, the possibility of recovering and recycling the silicon carbide(SiC) from a silicon sludge by removing Fe and Si impurities was investigated. Si and SiC were separated from the silicon sludge using centrifugation. The separated SiC concentrate consisted of Fe, Si and SiC, in which Fe and Si were removed to recover the pure SiC. Leaching with acid/alkali solution was compared with the vapor-phase chlorination. The Fe concentration removed in the SiC was 49 ppm, and it was separated by leaching with 1 M HCl solution at $80^{\circ}C$ for 1 h. The Si concentration removed in the SiC was 860 ppm, and it was separated by leaching with 1M NaOH solution at $50^{\circ}C$ for 1 h. The SiC concentrate was chlorinated in a tubular reactor, 2.4 cm in diameter and 32 cm in length. The boat filled with SiC concentrate was located at the midpoint of the alumina tube, then, the chlorine and nitrogen gas mixture was introduced. The Fe and Si concentration removed in the SiC were 48 ppm and 405 ppm, respectively, at $500^{\circ}C$ reactor temperature, 4 h reaction time, 300 cc/min gas flow rate, and 10% $Cl_2$ gas mole fraction.

• Resources Recycling
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• v.27 no.1
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• pp.14-21
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• 2018

The rapid increase in the consumption of products that contain rare metals has highlighted the importance of recycling and recovering resources from these products when they enter the waste stream. Among various metal resources that can be recovered, this study analyzes the waste streams of cobalt and palladium to determine how their waste resource circulation can be improved at each stage of the waste stream. The findings of this study point to improvements and strategies that can be made at individual stages. First, at the discharge/import stage, the implementation of tariff quotas for specific recycled metal resources is suggested to allow the systemic categorization of waste metals as resources. At the collection/discarding stage, a major problem is the instability in the supply of scrap metals, which may be better managed by changing the bidding process for the scrap metals. At the pretreatment stage, possible areas for improvement are uncovered concerning technical areas, such as technological development and improving the efficiency of material recycling, as well as policy-wise, for instance, expanding the regulation for manufacturers to produce products that are designed to facilitate resource recovery, increasing incentive for closed recycling, and refining the guidelines and standards for recycling. At the resource recovery stage, as the waste metal recycling industry consists of businesses that vary in size, policies to promote cooperation and coexistence between large and smaller enterprises will benefit the industry in the long-run. Lastly, at the product production/export stage, a tariff on exporting waste resources that contain cobalt and palladium will help control the amount of waste metals that are shipped abroad.

• The Journal of the Korea Contents Association
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• v.10 no.2
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• pp.72-80
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• 2010

The 1Gbps clock and data recovery (CDR) circuit using the proposed multi-point phase detector (PD) is presented. The proposed phase detector generates up/down signals comparing 3-point that is data transition point and clock rising/falling edge. The conventional PD uses the pulse width modulation (PWM) that controls the voltage controlled oscillator (VCO) using the width of a pulse period's multiple. However, the proposed PD uses the pulse number modulation (PNM) that regulates the VCO with the number of half clock cycle pulse. Therefore the proposed PD can controls VCO preciously and reduces the jitter. The CDR circuit is tested using 1Gbps $2^{31}-1$ pseudo random bit sequence (PRBS) input data. The designed CDR circuit shows that is capable of recovering clock and data at rates of 1Gbps. The recovered clock jitter is 7.36ps at 1GHz and the total power consumption is about 12mW. The proposed circuit is implemented using a 0.18um CMOS process under 1.8V supply.

• Korean Parent-Child Health Journal
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• v.4 no.1
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• pp.1-18
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• 2001

Fatigue after delivery affect women's birth experience and interrupt the process of labor. Finally woman cannot have a positive birth result and will experience a postpartum fatigue. But researches about fatigue during the labor are lacked. Nurse help adapting a mother's role, bonding with new baby, recovering after birth, and improving woman's quality of life through decreasing fatigue during the labor and intercepting a continued postpartum fatigue. So it is very important that measuring a fatigue and confirming relationships between fatigue and factors affecting fatigue. The purpose of this study was measuring the level of fatigue within 4hours after delivery and identifing factors affecting fatigue. The ultimate goal was to contribute to improving a birth experience and adapting after birth through decreasing the level of fatigue and interventions. The data was collected for this study at the hospital of two universities and the third hospital in Seoul from Aug. 15. to Nov. 10. 2000. The subjects were 106 of mothers who deliveried a normal newborn and were tested within four hours after birth. The instruments were The Visual Analogue Scale for fatigue, The State Anxiety Inventory, and The Labor Support Inventory. The data were analyzed by using percentage, mean, SD, t-test, ANOVA, Pearson correlation. The results of this study were as follows; (1) The level of fatigue during the labor was 61.48point. (2) The deferences according to general and obstetric character affecting fatigue founded that there were Significant differences according to job(t=2.659, p=0.009), and the type of delivery(t=-2.035, p=0.044). (3) The deferences according to factors affecting fatigue revealed that there was significant difference according to quality of sleep(F=2.935, p=0.037). The significant fatigue and the fatigue after delivery was anxiety(r=0.343, p=0.000). The above findings indicate that the level of fatigue during the labor is higher than during pregnancy and postpartum. Woman having a job, delivering by vacuum was more fatigued. The level of fatigue according to a quality of sleep was significant difference. The poor quality of sleep, higher level of fatigue. And the more anxiety after delivery, the more fatigue. So, the variable nursing interventions for lessening the level of fatigue through appling the situation for rest, relaxation during the labor to reserve energy, and decreasing anxiety should be provided for mothers.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.11
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• pp.5514-5521
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• 2013

This study is an experiment to look into recovering process after maximum anaerobic exercise of career wrestlers and their basic fitness. First, group time results in anaerobic power test did not show meaningful differences between groups in PP, MP, LP field. Second, blood glucose showed meaningful difference in 5-year wrestlers group according to time-wise result (p<.001). Third, time-wise results in blood lactic acid concentration showed meaningful difference all in 5-year, 10-year and 15-year career wrestlers group (p<.001). Fourth, side step and general reaction did not show meaningful differences in all the 3 groups. In conclusion, increase or decrease was seen from and also significant differences were seen from the change of anaerobic power, glucose, lactic acid, concentration, basic physical strength reaction which have influence over athletic performance of players after anaerobic exercise. It was found that 5-year career players group was good at variables of power test and glucose. Reason why recovery capability in connection with degree of fatigue was poor in 15-year career players group seemed to have correlation between career and age.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.10A
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• pp.1113-1122
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• 2004

This paper is basically to achieve the high-availability and high-reliability of the control system from the implementation of the fault-tolerant system using the hot-standby sparing technique. To meet the objective, we design and implement a board with fault tolerance I/O bus to detect the fault. Warm-standby sparing technique is the fault tolerance technique usually used for switching control system in present. This technique can be easily implemented, but can not detect the fault quickly and can malfunction because of the hardware fault. The hot-standby sparing fault tolerant technique implemented in this paper is consists of dual processor modules and a I/O processor using fault tolerant I/O bus. The proposed method can find the faults as soon as possible, so it can prevent from wrong operation. Also it is possible to normal re-service due to the short recovering time. To implement the fault-tolerant dual system with fault detection be, two daughter, called FTMA and FTIA, boards designed and implemented are applied to the system. And we also simulated the proposed method to verify the high-availability and high-reliability of the control system using Markov process.