• Asian Journal of Atmospheric Environment
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• v.2 no.1
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• pp.34-46
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• 2008

Emissions inputs for use in air quality modeling of Korea were generated with the emissions inventory data from the National Institute of Environmental Research (NIER), maintained under the Clean Air Policy Support System (CAPSS) database. Source Classification Codes (SCC) in the Korea emissions inventory were adapted to use with the U.S. EPA's Sparse Matrix Operator Kernel Emissions (SMOKE) by finding the best-matching SMOKE default SCCs for the chemical speciation and temporal allocation. A set of 19 surrogate spatial allocation factors for South Korea were developed utilizing the Multi-scale Integrated Modeling System (MIMS) Spatial Allocator and Korean GIS databases. The mobile and area source emissions data, after temporal allocation, show typical sinusoidal diurnal variations with high peaks during daytime, while point source emissions show weak diurnal variations. The model-ready emissions are speciated for the carbon bond version 4 (CB-4) chemical mechanism. Volatile organic carbon (VOC) emissions from painting related industries in area source category significantly contribute to TOL (Toluene) and XYL (Xylene) emissions. ETH (Ethylene) emissions are largely contributed from point industrial incineration facilities and various mobile sources. On the other hand, a large portion of OLE (Olefin) emissions are speciated from mobile sources in addition to those contributed by the polypropylene industry in point source. It was found that FORM (Formaldehyde) is mostly emitted from petroleum industry and heavy duty diesel vehicles. Chemical speciation of PM2.5 emissions shows that PEC (primary fine elemental carbon) and POA (primary fine organic aerosol) are the most abundant species from diesel and gasoline vehicles. To reduce uncertainties in processing the Korea emission inventory due to the mapping of Korean SCCs to those of U.S., it would be practical to develop and use domestic source profiles for the top 10 SCCs for area and point sources and top 5 SCCs for on-road mobile sources when VOC emissions from the sources are more than 90% of the total.

• Journal of the Korean Society of Propulsion Engineers
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• v.19 no.2
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• pp.17-28
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• 2015

In this paper, it is accomplished to design a control method for such an actuation system of simplified ON/OFF mechanism with actuation command limit. First of all, based on experimental data, the modeling works for nonlinear/linear actuation dynamics are performed, which are govern by PWM command as a control input. Using the linearized model, a classical PI control method is designed to satisfy the aimed control performance requirements, and a control algorithm is proposed to realize the required control performance in the effective control region through resolving the issue for the PWM command limit which reduces the control performance. Finally, through control simulations, the design method is verified and the corresponding control performance improvement is evaluated.

• Journal of Digital Convergence
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• v.13 no.1
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• pp.275-281
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• 2015

The recent health care is growing rapidly want to receive offers users a variety of medical services, can be exploited easily exposed to a third party information on the role of the patient's hospital staff (doctors, nurses, pharmacists, etc.) depending on the patient clearly may have to be classified. In this paper, in order to ensure safe use by third parties in the health care environment, classify the attributes of patient information and patient privacy protection technique using hierarchical multi-property rights proposed to classify information according to the role of patient hospital officials The. Hospital patients and to prevent the proposed method is represented by a mathematical model, the information (the data consumer, time, sensor, an object, duty, and the delegation circumstances, and so on) the privacy attribute of a patient from being exploited illegally patient information from a third party the prevention of the leakage of the privacy information of the patient in synchronization with the attribute information between the parties.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.2
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• pp.1073-1083
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• 2015

As an empirical study focused on how transactive memory concept influence the four processes of knowledge growth, this study aimed at explaining the function of transactive memory in the dynamic process of knowledge growth. To verify the research model, this study carried out a path analysis of 130 team memebers and as a result, part of the team transactive memory measurements does affect the knowledge growth. Consequentially, transactive memory especially based on team level, is relevant with knowledge growth. According to team level, this study targeted at the team members, and by adopting the team transactive memory concept in Cognitive Psycology, theoretically explained and analysed how to approach personal knowledge in internal organizations. To accelerate the knowledge process, the work should be modified collaboratively by trusting the team members' duty relations more than specialized knowledge. Furthermore, managers had better assign team members the work where they can make the most of their personal knowledge, and this study presented that the whole team performance could be improved by doing that.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.11
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• pp.4745-4750
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• 2011

A HIL(hardware-in-the-loop) system was established and the simulation was carried out to determine whether the system operates normally. The system consists of turbocharger test bench, HIL platform with real time S/W and DAQ, and engine model using Matlab/Simulink. In the simulation the supplied fuel rate is changed step-by-step from 1.8944 kg/h to 4.7360 kg/h. The change of air-fuel ratio is analyzed and observed whether the air-fuel ratio follow the target air-fuel ratio 32. When the supplied fuel rate is changed, the air-fuel ratio is converged to the target air-fuel ratio after about 20 seconds. And the vane duty ratio of turbine and the boost pressure of compressor are also changed properly. Therefore this HIL system can be used to develop the new turbocharger and improve the performance of the modified turbocharger.

• Resources Recycling
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• v.29 no.4
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• pp.45-50
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• 2020

Producer and distributor of electrical and electronic equipment may directly collect waste electrical and electronic equipment that falls under the class to which the equipment they distributed belongs, or may join KERC(Korea Electronic Recycling Cooperative) and have KERC fulfill the duty to collect on behalf. In this study, the system of calculating the financial contributions is reviewed, and then the defined problems and improvement plan are proposed. First, the standard operation and time should be set for collection and transportation costs, taking into account the operation by collection type. Second, since there is a difference in the screening method of the recycling center, the standard cost for the allocation factor should be set by reflecting the difference in these methods and the characteristics of the product line being processed. Third, it is necessary to secure a budget of sufficient size by determining the median or average value rather than the minimum value in the forecast model for visit collection. This study is suggesting in that it examines the problems of the allotted contributions paid by the mutual aid members to KERC and suggests ways to improve them.

• Journal of Korean Clinical Nursing Research
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• v.25 no.3
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• pp.294-302
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• 2019

Purpose: The purpose of this study was to investigate the wage structure of hospital nurses in Korea and to analyze the factors that determine the level of nurses' wages. Methods: First, a mobile survey on nurses' wages was conducted with a total of 3,742 nurses working in hospitals. A literature review was also done. Second, a regression model was applied to analyze the determinants of nurses' wages. Results: The average monthly wage of 3,742 nurses based on the survey was KRW 3,588,000 and the standardized monthly income of 3,742 nurses was estimated to be KRW 3,364,000 as of the end of 2018. The results of regression analysis(R²=61.7%) showed that gender, nursing experience, designated night duty, ownership, and number of beds were statistically significant variables for nurses' wages at 1% significance level. The monthly wage of nurses working in total nursing care wards was not significantly different from those working in other wards at 5% significance level. Conclusion: The substantial difference in nurses' wages according to job career, hospital size, region, etc may result in the low proportion of nurses with more than three to five years of service experience and the high turnover of less-experienced workers. Consideration should be given to adjust the gap in wage level and a standard nurse wage system could be effective measures.

• Journal of Power Electronics
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• v.19 no.1
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• pp.190-200
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• 2019

The flyback converter, which can be regarded as a nonlinear time-varying system, has complex dynamics and nonlinear behaviors. These phenomena can affect the stability of the converter. To simplify the modeling process and retain the information of the output capacitor branch, a special sampled-data model of a peak current-mode (PCM) controlled flyback converter is established in this paper. Based on this, its dynamic behaviors are analyzed, which provides guidance for designing the circuit parameters of the converter. With the critical stability boundary equation derived by a Jacobian matrix, the stable operation range with a varied output capacitor, proportional coefficient of error the amplifier, input voltage, reference voltage and slope of the compensation ramp of a PCM controlled flyback converter are investigated in detail. Research results show that the duty ratio should be less than 0.5 for a PCM controlled flyback converter without ramp compensation to operate in a stable state. The stability regions in the parameter space between the output capacitor and the proportional coefficient of the error amplifier are enlarged by increasing the input voltage or by decreasing the reference voltage. Furthermore, the ramp compensation also can extend to the stable region. Finally, time-domain simulations and experimental results are presented to verify the theoretical analysis results.

• Journal of Biomedical Engineering Research
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• v.43 no.1
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• pp.1-10
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• 2022

Non-alcoholic fatty liver disease(NAFLD) is excessive hepatic lipid accumulation mainly caused by obesity. This study aimed to evaluate whether micro-current stimulation(MCS) could modulate lipid metabolism regarding the Sirt1/AMPK pathway, fatty acid β-oxidation pathway, and lipolysis and lipogenesis-related factors in FL83B cells. For the NAFLD cell model, FL83B cells were treated with oleic acid for lipid accumulation. MCS were stimulated for 1 hr and used frequency 10 Hz, duty cycle 50%, and biphasic rectangular current pulse. The intensity of MCS was divided into 50, 100, 200, and 400 ㎂. Through the results of Oil red O staining, it was confirmed that MCSs with the intensity of 200 ㎂ and 400 ㎂ significantly reduced the degree of lipid droplet formation. Thus, these MCS intensities were applied to western blot analysis. Western blot analysis was performed to analyze the effects of MCS on lipid metabolism. MCS with the intensity of 400 ㎂ showed that significantly activated the Sirt1/AMPK pathway, a key pathway for regulating lipid metabolism in hepatocytes, and fatty acid β-oxidation-related transcription factors. Moreover, it activated the lipolysis pathway and suppressed lipogenesis-related transcription factors such as SREBP-1c, FAS, and PPARγ. In the case of MCS with the intensity of 200 ㎂, only PGC1α and SREBP-1c showed significant differences compared to cells treated only with oleic acid. Taken together, these results suggested that MCS with the intensity of 400 ㎂ could alleviate hepatic lipid accumulation by modulating lipid metabolism in hepatocytes.

• The Journal of the Korea Contents Association
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• v.22 no.6
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• pp.506-517
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• 2022

The study was conducted to identify and clarify the conceptual definitions and attributes of caregiving satisfaction in family caregivers of patients with dementia. The hybird model was used to perform the concept analysis of caregiving satisfaction. Results from both the theoretical review and a field study including 7 participants were included in final process. The concept of caregiving satisfaction was found to have three dimensions with seven attributes. Caregiving satisfaction by family caregivers of patients with dementia was defined as positive of aspects of caregiving usually experienced in three dimensions such as interpersonal dimensions (accomplishing a duty, reciprocity, strengthening of the relationship), role performance dimensions (feeling of accomplishment, emotional reward, emotional comfort) and meaning of role dimensions (positive meaning-making). Based on the results, a tool for measuring caregiving satisfaction among Koreans family caregivers of patients with dementia and effective programs for enhancing caregiving satisfaction should be developed in future studies.