• Journal of Environmental Impact Assessment
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• v.5 no.1
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• pp.95-105
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• 1996

Meteorological Joint Frequency Function required indispensably in long-term air quality prediction models were discussed for practical application in Korea. The algorithm, proposed by Turner(l964), is processed with daily solar insolation and cloudiness and height basically using Pasquill's atmospheric stability classification method. In spite of its necessity and applicability, the computer program, called STAR(STability ARray), had some significant difficulties caused from the difference in meteorological data format between that of original U.S. version and Korean's. To cope with the problems, revised STAR program for Korean users were composed of followings; applicability in any site of Korea with regard to local solar angle modification; feasibility with both of data which observed by two classes of weather service centers; and examination on output format associated with prediction models which should be used.

• Proceedings of the KIEE Conference
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• 1995.11a
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• pp.453-455
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• 1995

In electrostatic airclean filter, the collection efficiency defends on particle charge in the ionizer section. The effect of electrostatic airclean filter condition (deposition of dust, variation of corona discharge current) on corona discharge characteristics was well studied. However, it seems not to be studied on corona discharge characteristics of electrostatic airclean filter respect to contaminated electrode which is caused by practical use. In this paper, Long-term(60days) effects are studied experimentally by two methods. The one is ozone concentration, the other is collection efficiency. Generation of ozone level was increased but collection efficiency was slightly reduced in long-term used electrostatic airclean filter.

• Asia-Pacific Journal of Business
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• v.12 no.4
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• pp.253-270
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• 2021

Purpose - The main purpose of this study is to measure and evaluate the level of national liabilities that Korea's national finances can afford. Specifically, the concepts of national debt and national liability are clarified, and the appropriate level of national liabilities is measured in terms of short-term fiscal crisis, mid-to-long-term fiscal crisis, and GDP. Based on these measurements of fiscal crisis, this study would like to propose national fiscal management plans. Design/methodology/approach - In order to clearly recognize the difference between the national debt and the national liability, this study examines the data from 2013 to 2020. In addition, this study uses data from the national financial statements from 2013 to 2018 to measure the appropriate level of national liabilities in terms of fiscal crisis management. Findings - Short-term fiscal crises, measured by current ratios, will not occur. Nevertheless, in view of the cash flow compensation ratio, the short-term bankruptcy of the national finances of Korea depends on the re-borrowing of short-term borrowings and current and long-term borrowings. In addition, in order to manage the mid-to long-term financial crisis, it is necessary to pay attention to the liability growth rate rather than the liability size. Research implications or Originality - While previous studies focused on the appropriate level of national debt, this study was differentiated as a study focused on the level of national liability coverage. It is expected that the results of this study will be used to manage the national fiscal soundness.

• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.5
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• pp.657-663
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• 2016

In this work, a novel silicon (Si) based floating body synaptic transistor (SFST) is studied to mimic the transition from short-term memory to long-term one in the biological system. The structure of the proposed SFST is based on an n-type metal-oxide-semiconductor field-effect transistor (MOSFET) with floating body and charge storage layer which provide the functions of short- and long-term memories, respectively. It has very similar characteristics with those of the biological memory system in the sense that the transition between short- and long-term memories is performed by the repetitive learning. Spike timing-dependent plasticity (STDP) characteristics are closely investigated for the SFST device. It has been found from the simulation results that the connectivity between pre- and post-synaptic neurons has strong dependence on the relative spike timing among electrical signals. In addition, the neuromorphic system having direct connection between the SFST devices and neuron circuits are designed.

• Journal of The Korean Society of Agricultural Engineers
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• v.46 no.5
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• pp.41-52
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• 2004

In this study, parameters of long and short term runoff model were optimized using genetic algorithm as a basic research for integrated water management in a watershed. In case of Korea where drought and flood occurr frequently, the integrated water management is necessary to minimize possible damage of drought and flood. Modified TANK model was optimized as a long term runoff model and storage-function model was optimized as a short term runoff model. Besides distinguished parameters were applied to modified TANK model for supplementing defect that the model estimates less runoff in the storm period. As a result of application, simulated long and short term runoff results showed 7% and 5% improvement compared with before optimized on the average. In case of modified TANK model using distinguished parameters, the simulated runoff after optimized showed more interrelationship than before optimized. Therefore, modified TANK model can be applied for the long term water balance as an integrated water management in a watershed. In case of storage-function model, simulated runoff in the storm period showed high interrelationship with observed one. These optimized models can be applied for the runoff analysis of watershed.

• Journal of the Korea Convergence Society
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• v.6 no.6
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• pp.213-219
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• 2015

This study examines how the features of communication on Social Network Service(SNS) affect building faculty trust and long-term orientation in professor-student relationships. The research model was developed based on the previous research about communication, SNS and relationship development. The researcher surveyed 210 students to collect research data, and 195 questionnaires were analyzed using SmartPLS. The results indicate that the quality, frequency, interactivity and openness of communication on SNS affect positively on faculty trust. Moreover, the quality, frequency and openness of communication on SNS affect positively on long-term orientation, whereas interactivity does not. This mean that faculty trust plays a mediating role between interactivity and long-term orientation.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.561-568
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• 2005

The factors affecting the long-term design strength of geogrid can be classified into factors on creep deformation, installation damage, temperature, chemical degradation and biological degradation. Especially, creep deformation and installation damage are considered as main factors to determine the long-term design strength of geogrid. Current practice in the design of reinforced soil is to calculate the long-term design strength of a reinforcement damaged during installation by multiplying the two partial safety factors, $RF_{ID} and RF_{CR}$. This method assumes that there is no synergy effect between installation damage and creep deformation of geogrids. Therefore, this paper describes the results of a series of experimental study, which are carried out to assess the combined effect of installation damage and creep deformation for the long-term design strength of geogrid reinforcement. The results of this study show that the tensile strength reduction factors, RF, considering combined effect between installation damage and creep deformation is less than that calculated by the current design method.

• Journal of East-West Nursing Research
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• v.25 no.1
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• pp.81-89
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• 2019

Purpose: This study aimed to investigate influencing factors on nursing competency of nurses in long-term care hospitals. Methods: A descriptive research design was used with a convenience sample of 150 nurses. Data were collected from Feb 15 to Mar 8, 2017 using self-reported questionnaires and analyzed by descriptive statistics, t-test, ANOVA, Pearson's correlation coefficient, and multiple regression analysis using the SPSS/WIN 18.0 program. Results: The mean scores of self-efficacy, organizational citizenship behavior and nursing competency were 3.84 out of 5, 3.77 out of 5 and 3.80 out of 5, respectively. Nursing competency was positively correlated with self-efficacy (r=.63, p<.001) and organizational citizenship behavior (r=.64, p<.001). Factors influencing on nursing competency were self-efficacy (${\beta}=.38$, p<.001), organizational citizenship behavior (${\beta}=.37$, p<.001) and Clinical career(${\beta}=.14$, p=.011), which explained 51% of the variance. Conclusion: Based on the finding of this study, it is necessary to develop education and intervention programs in order to increase the nursing competency for nurses in long-term care hospitals.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.20 no.4
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• pp.429-453
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• 2022

Numerical modeling and scenario composition are needed to characterize the geological environment of the disposal site and analyze the long-term evolution of natural barriers. In this study, processes and features of the hydro-mechanical behavior of natural barriers were categorized and represented using the interrelation matrix proposed by SKB and Posiva. A hydro-mechanical coupled model was evaluated for analyzing stress field changes and fracture zone re-activation. The processes corresponding to long-term evolution and the hydro-mechanical mechanisms that may accompany critical processes were identified. Consequently, practical numerical methods could be considered for these geological engineering issues. A case study using a numerical method for the stability analysis of an underground disposal system was performed. Critical stress distribution regime problems were analyzed numerically by considering the strata's movement. Another case focused on the equivalent continuum domain composition under the upscaling process in fractured rocks. Numerical methods and case studies were reviewed, confirming that an appropriate and optimized modeling technique is essential for studying the stress state and geological history of the Korean Peninsula. Considering the environments of potential disposal sites in Korea, selecting the optimal application method that effectively simulates fractured rocks should be prioritized.

• The Korea Journal of Herbology
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• v.27 no.6
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• pp.77-81
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• 2012

Objectives : The purpose of this research was to examine the oriental medical term 'Yukjin(in chinese, liuchen)' i.e. 'good long-term storage of the six oriental medicinal herbs'. Yukjin has meant the six sorts of drugs which were well known for the older they stored, the better efficacious they were. This research was carried out to obtain more conclusive information about the time and the reason of the giving a naming Yukjin, and to arrange Yukjin's properties, toxicities and processes. Methods : We investigated the documents recorded in the medical classics of Yukjin and did the current issues and recent experimental researches of these medicines. Results : 1. The properties and flavors of Yukjin are pungent and bitter. When they were stored for a long time after gathering, their toxicities and stimuli were growing thinner, regarded as positive clinically with age and they should be used after processing. 2. The efficacies of Yukjin are not always in proportion to storage period. In case, they are stored too long, their efficacies and qualities may be deteriorated though volatility or pungent flavors are enfeebled. Conclusions : Consequently, toxicities and strong flavors of Yukjin can be reduced in various processes. So the traditional theory of long-term preservation is not necessarily retained. It may be desirable to store them for 1 to 3 years after harvest, to safen their toxicities and adverse reactions in the way of processing. If we use them properly according to oriental medicine method, it will be effective on treating and preventing the various diseases.