• Journal of Korea Water Resources Association
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• v.43 no.9
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• pp.801-811
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• 2010

A three-dimensional numerical model called NEWTANK is employed to investigate solitary wave run-up with an internal wave-maker on a steep slope. The numerical model solves the spatially averaged Navier-Stokes equations for two-phase flows. The LES (large-eddy-simulation) approach is adopted to model the turbulence effect by using the Smagorinsky SGS (sub-grid scale) closure model. A two-step projection method is adopted in numerical solutions, aided by the Bi-CGSTAB (Bi-Conjugate Gradient Stabilized) method to solve the pressure Poisson equation for the filtered pressure field. The second-order accurate VOF (volume-of-fluid) method is used to track the distorted and broken free surface. A solitary wave is first internally generated and propagated over a constant water depth in the three-dimensional domain. Numerically predicted results are compared with analytical solutions and numerical errors are analyzed in detail. The model is then applied to study solitary wave run-up on a steep slope and the obtained results are compared with available laboratory measurements.

• Korean Journal of Plant Resources
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• v.33 no.1
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• pp.1-14
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• 2020

This study was conducted to analyze community structure and species composition of Pinus densiflora for. erecta Stand in Mt. Cheonchuk (653 m). Field survey was carried out from June to September in 2013. 74 plots (20×20 m) were set up, 5 herb layer plots (3×3 m) were constructed for each plot, and there, Diameter at Breast Heigh t(DBH), height, environmental factor, annual growth were measured. Vascular plants were surveyed as following; 66 family, 165 genus, 211 species, 2 sub species, 29 variety, 6 form 248 taxa. Results of cluster analysis for P. densiflora for. erecta forest, 3 communities were divided into; Quercus mongolica (P-1), Quercus variabilis (P-2) and Quercus aliena-Stephanandra incisa (P-3). There were significant environmental factors that organic layer, annual growth, CEC, total total nitrogen, organic matter and pH for each community. As a result of DCA, P-1 and P-2 were distributed large range of environmental factors but relatively limited in P-3. Distributions of herb layer were affected by sand, cation exchange capacity, silt and total nitrogen. Results of MRPP test for herb layer communities, it was significantly analyzed (A=0.003, P<0.008). Species diversity index was highly recorded in P-3 and influenced by cation exchange capacity, total nitrogen, annual growth in consequence of NMS analysis.

• Journal of Korean Academy of Nursing
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• v.28 no.3
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• pp.751-759
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• 1998

The study of the validity test on the self-monitoring scale for nurses In this study, both the literary survey as well as empirical research has been executed to test the validity of the scales that measure the construct of the self-monitoring scale. The self-monitoring scale could not be classified into five factors as Snyder suggested. Many other scholars (Briggs, Cheek and Buss, 1980) suggested 3 different classifications which was accepted by Snyder and Gangestad (1986). John, Cheek and Klohnen(1996) claimed a two-factor classification. As has been discussed, factor analysis is used to prove convergent validity within the factor and discriminant validity between the factors. However, depending on the researchers, many variations in classification of the factors were found and a lack of content and discriminant validity were found in the previous research findings. It is also important to note that Snyder's self-monitoring scale did not factor-load at over. 30 for all 25 items, regardless of how many factors could be classified. According to findings of this study, the self-monitoring scale neither classified as five, three or two factors nor factor loaded as hypothesized. It is also clear that Snyder's self-monitoring scale lacks convergent validity as the sub-factors of the scale failed to prove its uni-dimensionality. The A self-monit oring scale not only fail to overcome the problems of Snyder's self-monitori ng scale but even lost the attractiveness of the self-monitoring scale. In this study it was also found that the A self-monitoring scale was not classified in either in a two or three-factor classification as hypothesized. It is, of course, not desirable to use any scale that lacks convergent and discriminant validity even though it has been widely used and has held a great deal of influence on the field of social psychology. To overcome the shortcomings of Snyder's self-monitoring scale, Lennox and Wolfe(1984) suggested 13 items. This study was dedicated to test the validity and reliability of the scale, in which we found that the data presented in validity as the two factors were class ified and loaded as expected. Reliability was also proven by checking Cronbach's α for each factor and for the total items. In addition, a confirmatory factor analysis was executed for the 13 items using LISREL 8.12 program to confirm convergent validity in a two-factor classification. The model was fitting and sound : however, the self-monitoring scale was unfitted and not validated. Thus, it is recommended to use not the original nor the abbreviated self-monitoring scale but the 13 items in future studies. It should also be noted that items 7 and 13 should be removed to obtain better uni-dimensionality for the 13 items. These items loaded at over. 30, too high for the two factors in the test results of Factor analysis. In addition, it is necessary to double-check the cause of two-hold loading at over .30 for the two factors. It could be a problem caused by data or by the scale itself. Therefore, additional studies should follow to better clarify this matter.

• Geophysics and Geophysical Exploration
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• v.17 no.1
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• pp.34-44
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• 2014

Because offshore plant industry needs to design, deploy and operate much of equipment especially, the latest trend shows the installation of production facilities is augmented in the subsea. The installed facilities are very difficult to be repaired or changed because they are located in the subsea. For solving these problems, both the directly related information of the production like the optimal number, position and depth of wells and the distribution for effective operation and safety of equipment of subsea should be considered at the preliminary stage of FEED (Front End Engineering Design). The marine exploration is introduced in this paper for providing the fundamental technology to answer the questions related to above considering points. First, some kinds of the offshore plant facilities are enumerated and aims of marine exploration for the offshore oil/gas development are summarized. In addition to it, the main roles of marine survey, in the step of designing and installing offshore oil-gas plant, development are briefly listed. And then foreign examples are shown to help the reader's understand. This paper is hoped to be helpful for understanding the marine exploration that can be applied to offshore oil/gas plant and to be contributed to developing the domestic techniques in this field for the future.

• Journal of Environmental Science International
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• v.10 no.1
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• pp.21-25
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• 2001

The Keum river has been utilized for drinking water supply of several city including Kunsan city and is deepening pollution state due to numerous municipal and industrial discharges. The concentration BOD in river is affected by the organic loading from a tributary and the algae biomass that largely happen to under eutrophication state. In the eutrophic water mass such as the Keum river, the autochthonous BOD was very important part for making a decision of water quality management, because it was accounted for majority of the total BOD. The predict of water quality has important meaning for management of water quality pollution of the Keum river. The purpose of this study will manage and predict water quality of the Keum river using QUAL-2E model considering the autochthonous BOD. The estimation of autochthonous BOD represented that the relationship between BOD and chlorophyll a. The regression equation was shown to be autochthonous BOD=$\beta$(sub)5$\times$chlorophyll a. The results of this study may be summarized as followed; The QUAL-2E model was calibrated with the data surveyed in the field of the study area in June, 1998. The calculated value by QUAL-2E model are in good agree to measured value within relative error of 7.80~20.33%. Especially, in the case of the considering autochthonous BOD, the calculated value of BOD were fairly good coincided with the observed values within relative error of 15%. But the case of not considering autochthonous BOD, relative error of BOD was shown to be 43.2%. In order to attain II grade of water quality standard in Puyo station which has a intake facility of water supply, we reduced to the pollutants loading of tributaries. In the case of removed 100% BOD of tributaries, the BOD of Puyo station was 4.07mg/$\ell$, belong to III grade of water quality standard. But in the case of removed 88% nutrient of tributaries, it was satisfied to II grade of water quality standard as below 3mg/$\ell$ of BOD. For estimation of autochthonous BOD in Keum river, we are performed simulating in accordance with reduction of nutrient load(50~100%) under conditions removal 90% organic load. Occupancy of autochthonous BOD according to nutrient loading reductions were varied from 25.97~79.51%. Occupancy of autochthonous BOD was shown to be a tendency to increasing in accordance with reduction of nutrient loading. Showing the above results, the nutrient that one of the growing factor of algae was important role in decision of BOD in the Keum river. For the water quality management of the Keum river, therefore, it is necessary to considering autochthonous BOD and to construction of advanced sewage treatment plant for nutrient removal.

• Journal of Venture Innovation
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• v.3 no.1
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• pp.87-99
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• 2020

This study empirical analysed how student's major satisfaction affected job-seeking stress. It also analysed the mean differences of major satisfaction and job-seeking stress between two groups(IPP experienced, non-experienced groups). 200 data were collected from the field survey questionnaires administered to a quota sample of university students who had IPP experience or non-experience. For hypothesis testing, the IBM SPSS Statistics 24.0 was used. As a result of empirical research analysis, first, it was found that major satisfaction had a negative effect on job-seeking stress. Among major satisfaction sub categories, subject satisfaction had negative effects on cognitive and physical stress, and relationship satisfaction also had negative effects on cognitive and physical stress. On the other hand, general satisfaction had a negative effect only on emotional stress. Second, there was a significant difference between major satisfaction and job-seeking stress. Major satisfaction of IPP experience group was high, and the job-seeking stress was low. Third, in the group of students who practiced IPP, subject satisfaction had a negative effect on emotional and physical stress, whereas subject satisfaction in the group of students who did not practice IPP had no significant effect on job-seekingt stress. In the case of relationship satisfaction, only non-practice groups had a negative effect on cognitive stress and physical stress. In the case of general satisfaction, only the IPP group showed negative effects on emotional stress. The results of this study supported the preceding studies that major satisfaction had an effect on job-seeking stress, and the study was meaningful in that it confirmed that there were differences between the IPP experienced, non-experienced groups. Based on this results, academic and practical implications were suggested.

• Journal of the Korea Convergence Society
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• v.11 no.11
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• pp.361-371
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• 2020

The purpose of this study was to analyze the path that the elderly discrimination experiences and sense of loss lead to suicidal ideation by verifying the influence of the elderly's discrimination experience on suicidal ideation and the mediating effect of sense of loss. To this end, questionnaire a survey was conducted on 400 elderly people aged 65 years or older who used 10 elderly welfare centers using stratified sampling of 31 cities, counties, and districts in Gyeonggi-do. Additionally, a total of 380 samples were finally analyzed excluding dishonest responses. As a result of the study, first, the more individual and social discrimination experiences, which are sub-factors of the elderly discrimination experience, increased suicidal ideation. Second, individual discrimination experiences were found to has a static effect on suicidal ideation through partial mediation of sense of loss. Third, the experience of social discrimination showed a static effect on suicidal ideation by perfect mediating the sense of loss. Therefore, it was found that the sense of loss acts as a risk factor for the elderly's suicidal ideation. Based on the research results, the urgent need for institutional supplementation to prevent the elderly's social discrimination experiences was suggested, and practical implications for preventing elderly suicide by resolving the sense of loss in the elderly welfare practice field were suggested.

• Carbon letters
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• v.28
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• pp.31-37
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• 2018

This paper examines a simple one-step and catalyst-free method for synthesizing carbon nanoparticles from aliphatic alcohols and n-hexane with linear molecule formations by using a stable solution plasma process with a bipolar pulse and an external resistor. When the external resistor is adopted, it is observed that the current spikes are dramatically decreased, which induced production of a more stable discharge. Six aliphatic linear alcohols (methanol-hexanol) containing carbon with oxygen sources are studied as possible precursors for the massive production of carbon nanoparticles. Additional study is also carried out with the use of n-hexane containing many carbons without an oxygen source in order to enhance the formation of carbon nanoparticles and to eliminate unwanted oxygen effects. The obtained carbon nanoparticles are characterized with field emission-scanning electron microscopy, energy dispersive X-ray spectroscopy, and Raman spectroscopy. The results show that with increasing carbon ratios in alcohol content, the synthesis rate of carbon nanoparticles is increased, whereas the size of the carbon nanoparticles is decreased. Moreover, the degree of graphitization of the carbon nanoparticles synthesized from 1-hexanol and n-hexane with a high carbon (C)/oxygen (O) ratio and low or no oxygen is observed to be greater than that of the carbon nanoparticles synthesized from the corresponding materials with a low C/O ratio.

• Journal of Korean Society of Forest Science
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• v.101 no.2
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• pp.213-219
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• 2012

The $5^{th}$ national forest inventory (NFI5) has been reorganized to annual inventory system for providing multi-resources forest statistics at a point in time. The objective of this study is to evaluate statistical estimators for estimating forest growing stock in Chungcheongbuk-Do from annual inventory data. When comparing two estimators; simple random sampling (SRS) and double sampling for post-stratification (DSS), for estimating mean forest growing stock ($m^3/ha$) at each surveyed year, the estimate for DSS in which a population of interest is stratified into three sub-population (forest cover types) was more precise than that for SRS. To combine annual inventory field data, three estimators (Temporally Indifferent Method; TIM, Moving Average; MA, and Weighted Moving Average; WMA) were compared. Even though the estimated mean for TIM and WMA is identical, WMA-DSS is preferred to provide more smaller variance of estimated mean and to adjust for catastrophic events at a surveyed year (so-called "lag bias") by annual inventory data.

• Korean Journal of Childcare and Education
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• v.5 no.2
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• pp.1-20
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• 2009

This paper is intended as an investigation of relation between pre-service kindergarten teacher's creative personality and teacher's efficacy. Subjects of this study were 160 third grade students of S collage & Y collage. They were major in infant or early childhood education and have an field practice experience of nurture and education. Tool for measurement is Creative Personality Scale of Ha Juhyun and TEBI(Teaching Efficacy Belief Instrument) teacher's efficacy test which is modified by Kim Sunnam. The collected data were analyzed by one-way ANOVA, post hoc Scheffe' test, Pearson's correlation and stepwise regression. The following results were obtained. First, there is no difference in creative personality according to academic grade, age, experience of leadership in collage. Second, there is a static relation between age of pre-service kindergarten teacher and teacher's efficacy especially personal teacher's efficacy. Third, points of creative personality is relative to teacher's efficacy, especially relative to personal teacher's efficacy. Among the sub-factors of creative personality, factors estimates teacher's personal efficacy are 'self belief, imagination and open mind'. On these ground, I comment on curriculum which will educate creative personality of pre-service kindergarten teacher.