• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.1
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• pp.121-126
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• 1998

This study is to examine the energy budget of Hexagrammos agrammus in the natural habitat, based on the von Bertalanffy's growth model using food consumption and growth data of the fish. The fish were collected at the coasts of Tongbaek Island in Pusan and Shinsu Island in Samchonpo, Korea. The standard energy budget model was adopted for this study and the model has the components of toed consumption (C), production (G), assimilation (A), absorption ($A_b$), catabolism (R), excreta (U) and feces (F). These components were expressed as mass unit, not as calorie unit as usual. Both the mass and the proportion of each component varied with age of the fish, The mass of annual excreta declined as the fish became older, while those of the other components increased with the age. The relationship between mean weight (W) and annual absorption ($A_b$) was a non-linear one with the equation of $A_b=4.592W^{0.666}$, while that between mean weight (W) and annual catabolism (R) was linear as R=0.007+0.567W. On the other hand, the annual food consumption (C) showed linear relations both with annual assimilation (A) and annual catabolism (R) as A= -7.026+0.061C and R=-20.749+0.048C, respectively.

• Journal of the Korean Society of Child Welfare
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• no.32
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• pp.69-97
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• 2010

The purpose of this study is to investigate the effects of high school students' academic problems such as academic stress and low academic achievement on suicidal ideation and the mediating effects of individual-level risk factors (e.g., depression, aggression) and protective factors (self-esteem, emotion regulation) on the relationship between academic problems and suicidal ideation. This study used data of three waves(2005-2007) from the Korea Youth Panel Survey(KYPS). The analyses were conducted on 2,093 academic high school students, who participated in this panel study. The results from structural equation modeling show that academic stress has positive effects on depression and aggression, but negative effect on self-esteem. Low academic achievement has positive effect on aggression but negative effect on self-esteem. Depression and aggression as individual-level risk factors have positive effects on suicidal ideation. In contrast, self-esteem and emotion regulation as individual-level protective factors have negative effects on suicidal ideation. The relationship between academic problems and suicidal ideation is mediated by depression, aggression, and self-esteem. Based on the study findings, practice implications for youth welfare are discussed to screen high-risk youths and to prevent adolescent suicide in advance.

• Nuclear Engineering and Technology
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• v.22 no.1
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• pp.20-28
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• 1990

In this study the migration experiment using packed column with crushed tuff was conducted as a basic research to develop migration model of radionuclides through geologic media. The main emphasis was put on evaluating the validity of migration models. For this, two models were introduced: one is the model which is based on the assumption of instantaneous equilibrium reaction and the other the model based on kinetic process such as intraparticle diffusion. The coefficient of hydrodynamic dispersion in packed column was determined using iodine as nonsorbing tracer. The hydrodynamic dispersion coefficient, D$_{L}$ was shown to be 0.11$\times$10$^{-2}$ $\textrm{cm}^2$/min under the condition of the column porosity of 0.483 and the average water velocity of 0.915$\times$10$^{-2}$ cm/min. The distribution coefficient, Kd of Cs-137 on crushed tuff was 11.3 cc/g at the concentration of 2$\times$10$^{-6}$ M and the temperature of 2$0^{\circ}C$. The breakthrough curve of Cs-137 through packed column was shown to have an asymmetric curve in which long trailing tail appears at the end part of the curve. The results obtained from the comparison of introduced models with experimental data indicated that the mass transfer model with intraparticle diffusion as rate-controlling step simulated the behaviors of Cs-137 migration more adequately, when compared with the bulk reaction model in which the assumption of instantaneous equilibrium reaction was maded. Consequently, the intraparticle diffusion was found to be an important factor in the migration of Cs-137 through packed column.n.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.11
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• pp.78-87
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• 2018

This study constructed a structural model and examined the fit and significance of the model to identify the influencing factors on the organizational commitment of ROTC cadets. The subjects of this study were 209 male students in grades 3 and 4 ROTC cadets of eight universities located in D, P, and G cities. Data were collected from April 13 to May 29, 2018. The data collected were analyzed by SPSS / WIN 20.0 and AMOS 21.0 programs. A positive correlation was observed between the ROTC instructor's leadership, self-efficacy, job satisfaction, and organizational commitment. Six of the six pathways of the hypothetical structural model were statistically significant. The hypothetical model showed a good fit for the data. The model fit indices were ${\chi}^2/df=1.51$, GFI=.98, AGFI=.90, NFI=0.98, NFI=.97, RMR=.02, RMSEA=.05, and TLI=.98. The ROTC Instructor's leadership and self-efficacy had direct and indirect effects on the organizational commitment. Job satisfaction had the strongest direct influence on organizational commitment. This model explained 73% of the variance in organizational commitment. Therefore, it is necessary to develop an effective education and intervention program that can enhance the ROTC instructor's leadership, self-efficacy, and job satisfaction to increase the organizational commitment of the ROTC cadets.

• The Korean Journal of Franchise Management
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• v.8 no.4
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• pp.33-43
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• 2017

Purpose - Previous studies about corporate image generally explore how corporate image affects a company's effectiveness from the consumer view. However this study attempts to explore the impacts of corporate image (reliability, friendly, corporate social responsibility, and innovation) on employees' altruistic behaviors in the franchise industry context. This study also examine whether organizational trust and affective commitment play a mediating role in the relationship between corporate image and employees' altruistic behaviors. The authors developed several hypotheses to achieve these purposes. Research design, data, and methodology - The data were collected from employees in food-service franchise companies located in Seoul, Korea. Among a total of 363 questionnaires distributed, 294(response rate of 81%) questionnaires were returned. After excluding 18 invalid respondent questionnaires, 276 valid questionnaires(response rate of 76%) were coded and analyzed using frequency, confirmatory factor analysis, correlations analysis, and structural equation modeling with SPSS 21 and SmartPLS 3.0. Result - The findings of the study are as follows: First, friendly, CSR, and innovation had positive effects on organizational trust, but reliability did not have a significant effect on organizational trust. Second, reliability and friendly of corporate image had positive effects on affective commitment, but CSR and innovation did have a significant effect on affective commitment. Third, organizational trust and affective commitment had positive effects on employees' altruistic behaviors. Conclusions - The aim of this study is to investigate the franchise corporate image as a significant influencing factor of employees' altruistic behaviors. The data were collected from only employees from franchising companies. The findings might vary from position to position. Future studies need to collect and compare data from managers. Future studies need to consider other variables that affect employees' altruistic behaviors. For example, leadership and market orientation might influence employees' attitude and behaviors. Also, future research should include other variables and it may have limitations in sample representative because of sampling franchise corporate in Seoul. Future studies will include franchise corporate all over the country. Future studies can also consider other variables (e.g., job performance and turnover intentions) to measure employee performance at the level of individuals and identify the impact of employee performance on business performance at the level of corporate.

• Journal of the Korean Society of Safety
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• v.14 no.1
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• pp.208-215
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• 1999

The creep behavior of a rapidly solidified and consolidated Al-9.45wt%Fe-4.45wt%Cr alloy were investigated in the stress range 40 to 115 MPa and temperature range 300(0.53Tm) to 441$^{\circ}C$(0.66Tm). It is of use to available aerospace and automobile industries for the improved performance of materials used at high temperature. Because Al alloys with improved creep resistance offer the potential for lower weight and reduced costs in aerospace and automobile components (e.g., structural members and engine parts) through the replacement of heavier and more costly materials, the safety in use at high temperature is good. The alloy is characterized by high stress exponents and activation energies for creep, which are greatly dependent on the stress and temperature. Because the creep stress is seen to cause a strongly significant enhancement of coarsening, the coarsening rate of the dispersed particles in all crept specimens is faster than that in isothermally annealed specimens. Dislocations connecting dispersoids are observed more cofrequently in crept specimens with higher stress and lower temperature. The creep strain rates in the power law creep regime were found to be predicted much better by the Shorty and Rosler/Arzt equation with the inclusion of a threshold stress and dislocation detachment mechanism. The dispersoids in this alloy were acting a source of void nucleation that finally leaded to ductile fracture within the grain so called intergranular. Each void was initiated, grown and failed at the dispersoids in the aluminium matrix. Grain boundary accommodation of the slip produced, which result in initiation of the void and then final transgranular fracture. Therefore, it was confirmed that these dispersoids played an important role in the fracture mechanism by the formation of $Al_{13}Fe_4$, $Al_{13}Cr_2$ and $Al_2O_3$.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.29 no.3
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• pp.145-151
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• 2023

In order to extend shelf life for rockfish fillets by modified atmosphere packaging (MAP), different package atmospheres were compared in the product quality preservation. Firstly, CO₂ solubility was measured at 0, 5, 10, and 15℃ to be incorporated into the mathematical model to predict the volume and CO₂ concentration of the package at expected storage temperature. The CO₂ solubility given in Henry's constant decreased with temperature to be fitted with a linear equation. Then air packaging as control and four MAP conditions of 100 g fillets were prepared and stored for duration of 5 days at 10℃ to compare them in the quality preservation effect. Four MAP conditions employed were CO₂(60):O₂(30):N₂(10), CO₂(60):O₂(0):N₂(40), CO₂(30):O₂(30):N₂(40) andCO₂(30):O₂(0):N₂(70). MAP conditions with high CO₂ concentration inhibited total aerobic bacteria, and the conditions containing O₂ led to low TVB-N. MAP of CO₂(60):O₂(30):N₂(10) was found to be the best condition for rockfish fillet preservation considering total aerobic bacteria growth and nitrogenous volatiles production.

• Korea Journal of Hospital Management
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• v.29 no.2
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• pp.57-79
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• 2024

Purpose: The present study identified the determinants in the development of intrapreneurial intention in small and medium-sized local hospitals. A careful literature review led to the development of a conceptual model which identified two types of employee competence-individual competence and managerial competence-to influence intrapreneurial orientation positively. It was hypothesized that intrapreneurial orientation predicts intrapreneurial intention and is mediated by intrapreneurial commitment. Methodology/Approach: The target population was chosen from two medical institutions of 'D' Hospital and 'E' Geriatric Hospital in Changwon City, South Korea. Samples were collected from 299 respondents who completed a structured questionnaire. Findings: The results from a structural equation modeling statistical analysis indicated that (1) individual competence and managerial competence positively and significantly predict intrapreneurial orientation, (2) intrapreneurial orientation positively and significantly influences intrapreneurial intention, (3) intrapreneurial commitment partially mediates the relation of intrapreneurial orientation to intrapreneurial intention, and (4) the mediation effect of intrapreneurial commitment was significant in the medical-personnel group, but not in the non-medical group. Practical Implications: Overall findings from the present work provide vital insights into understanding the preconditions for developing employee intrapreneurship in small and medium-sized local hospitals.

• Journal of the Korean Wood Science and Technology
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• v.2 no.2
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• pp.8-12
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• 1974

1. If one unity is given to the prongs whose ends touch each other for estimating the internal stresses occuring in it, the internal stresses which are developed in the open prongs can be evaluated by the ratio to the unity. In accordance with the above statement, an equation was derived as follows. For employing this equation, the prongs should be made as shown in Fig. I, and be measured A and B' as indicated in Fig. l. A more precise value will result as the angle (J becomes smaller. $CH=\frac{(A-B') (4W+A) (4W-A)}{2A[(2W+(A-B')][2W-(A-B')]}{\times}100%$ where A is thickness of the prong, B' is the distance between the two prongs shown in Fig. 1 and CH is the value of internal stress expressed by percentage. It precision is not required, the equation can be simplified as follows. $CH=\frac{A-B'}{A}{\times}200%$ 2. Under scheduled drying condition III the kiln, when the weight of a sample board is constant, the moisture content of the shell of a sample board in the case of a normal casehardening is lower than that of the equilibrium moisture content which is indicated by the Forest Products Laboratory, U. S. Department of Agriculture. This result is usually true, especially in a thin sample board. A thick unseasoned or reverse casehardened sample does not follow in the above statement. 3. The results in the comparison of drying rate with five different kinds of wood given in Table 1 show that the these drying rates, i.e., the quantity of water evaporated from the surface area of I centimeter square per hour, are graded by the order of their magnitude as follows. (1) Ginkgo biloba Linne (2) Diospyros Kaki Thumberg. (3) Pinus densiflora Sieb. et Zucc. (4) Larix kaempheri Sargent (5) Castanea crenata Sieb. et Zucc. It is shown, for example, that at the moisture content of 20 percent the highest value revealed by the Ginkgo biloba is in the order of 3.8 times as great as that for Castanea crenata Sieb. & Zucc. which has the lowest value. Especially below the moisture content of 26 percent, the drying rate, i.e., the function of moisture content in percentage, is represented by the linear equation. All of these linear equations are highly significant in testing the confficient of X i. e., moisture content in percentage. In the Table 2, the symbols are expressed as follows; Y is the quantity of water evaporated from the surface area of 1 centimeter square per hour, and X is the moisture content of the percentage. The drying rate is plotted against the moisture content of the percentage as in Fig. 2. 4. One hundred times the ratio(P%) of the number of samples occuring in the CH 4 class (from 76 to 100% of CH ratio) within the total number of saplmes tested to those of the total which underlie the given SR ratio is measured in Table 3. (The 9% indicated above is assumed as the danger probability in percentage). In summarizing above results, the conclusion is in Table 4. NOTE: In Table 4, the column numbers such as 1. 2 and 3 imply as follows, respectively. 1) The minimum SR ratio which does not reveal the CH 4, class is indicated as in the column 1. 2) The extent of SR ratio which is confined in the safety allowance of 30 percent is shown in the column 2. 3) The lowest limitation of SR ratio which gives the most danger probability of 100 percent is shown in column 3. In analyzing above results, it is clear that chestnut and larch easly form internal stress in comparison with persimmon and pine. However, in considering the fact that the revers, casehardening occured in fir and ginkgo, under the same drying condition with the others, it is deduced that fir and ginkgo form normal casehardening with difficulty in comparison with the other species tested. 5. All kinds of drying defects except casehardening are developed when the internal stresses are in excess of the ultimate strength of material in the case of long-lime loading. Under the drying condition at temperature of $170^{\circ}F$ and the lower humidity. the drying defects are not so severe. However, under the same conditions at $200^{\circ}F$, the lower humidity and not end coated, all sample boards develop severe drying defects. Especially the chestnut was very prone to form the drying defects such as casehardening and splitting.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.5
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• pp.315-321
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• 2004

To compare soil carbon contents by Tyurin method and dry combustion method, we carried out analysis for 212 samples of agricultural land in Korea. The average values of soil carbon contents analyzed by Tyurin method and dry combustion method were $17.47{\pm}10.80$ and $19.91{\pm}10.63g\;kg^{-1}$, respectively. Both methods were evaluated as acceptable methods for soil carbon contents as the results showed. The results showed that soil texture had little effect on analysis method of carbon contents. Highly significant linear regression equation, Y = 0.846X ($R^2=0.991$), was obtained between carbon contents analyzed by Tyurin method (Y) and dry combustion method (X). As a result of comparison with data of carbon contents of the two methods, about 69% of results at dry combustion method have exceeded to results at Tyurin method. Especially, differences between results at two methods became higher as carbon contents were increasing. Tyurin method has been advantages such as shorter analysis time for one sample, more recognition for carbon analysis, and no need for expensive analyzer, while dry combustion method has simpler procedure, no heavy metal wastes, and more samples for analysis at one time.