• Journal of the Korea Institute of Building Construction
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• v.24 no.2
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• pp.273-284
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• 2024

This study investigates the impact of international oil price fluctuations on overseas construction orders secured by domestic and foreign companies. The analysis employs statistical data spanning the past 20 years, encompassing international oil prices, overseas construction orders from domestic firms, and new overseas construction orders from the top 250 global construction companies. The correlation between these variables is assessed using correlation coefficients(R), determination coefficients(R²), and p-values. The results indicate a strong positive correlation between international oil prices and overseas construction orders. The correlation coefficient between domestic overseas construction orders and oil prices is found to be 0.8 or higher, signifying a significant influence. Similarly, a high correlation coefficient of 0.76 is observed between oil prices and new orders from leading global construction companies. Further analysis reveals a particularly strong correlation between oil prices and overseas construction orders in Asia and the Middle East, potentially due to the prevalence of oil-related projects in these regions. Additionally, a high correlation is observed between oil prices and orders for industrial facilities compared to architectural projects. This suggests an increase in plant construction volumes driven by fluctuations in oil prices. Based on these findings, the study proposes an entry strategy for navigating oil price volatility and maintaining competitiveness in the overseas construction market. Key recommendations include diversifying project locations and supplier bases; utilizing hedging techniques for exchange rate risk management, adapting to local infrastructure and market conditions, establishing local partnerships and securing skilled local labor, implementing technological innovations and digitization at construction sites to enhance productivity and cost reduction The insights gained from this study, coupled with the proposed overseas expansion strategies, offer valuable guidance for mitigating risks in the global construction market and fostering resilience in response to international oil price fluctuations. This approach is expected to strengthen the competitiveness of domestic and foreign construction firms seeking success in the international arena.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.26 no.5
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• pp.300-313
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• 2014

Most analytical solutions for wave-induced soil response have been mainly developed to investigate the influence of the progressive and standing waves on the seabed response in an infinite seabed. This paper presents a new analytical solution to the governing equations considering the wave-induced soil response for the partial standing wave fields with arbitrary reflectivity in a porous seabed of finite thickness, using the effective stress based on Biot's theory (Biot, 1941) and elastic foundation coupled with linear wave theory. The newly developed solution for wave-seabed interaction in seabed of finite depth has wide applicability as an analytical solutions because it can be easily extended to the previous analytical solutions by varying water depth and reflection ratio. For more realistic wave field, the partial standing waves caused by the breakwaters with arbitrary reflectivity are considered. The analytical solutions was verified by comparing with the previous results for a seabed of infinite thickness under the two-dimensional progressive and standing wave fields derived by Yamamoto et al.(1978) and Tsai & Lee(1994). Based on the analytical solutions derived in this study, the influence of water depth and wave period on the characteristics of the seabed response for the progressive, standing and partial standing wave fields in a seabed of finite thickness were carefully examined. The analytical solution shows that the soil response (including pore pressure, shear stress, horizontal and vertical effective stresses) for a seabed of finite thickness is quite different in an infinite seabed. In particular, this study also found that the wave-induced seabed response under the partial wave conditions was reduced compared with the standing wave fields, and depends on the reflection coefficient.

• Journal of Environmental Science International
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• v.17 no.6
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• pp.633-645
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• 2008

In order to investigate the variations and corelation among $PM_{10},\;PM_{2.5}\;and\;PM_1$ concentrations, the hourly concentrations of each particle sizes of 300nm to $20{\mu}m$ at a city, Gangneung in the eastern mountainous coast of Korean peninsula have been measured by GRIMM aerosol sampler-1107 from March 7 to 17, 2004. Before the influence of the Yellow Dust event from China toward the city, $PM_{10},\;PM_{2.5}\;and\;PM_1$, concentrations near the ground of the city were very low less than $35.97{\mu}g/m^3,\;22.33{\mu}g/m^3\;and\;16.77{\mu}g/m^3$, with little variations. Under the partial influence of the dust transport from the China on March 9, they increased to $87.08{\mu}g/m^3,\;56.55{\mu}g/m^3\;and\;51.62{\mu}g/m^3$. $PM_{10}$ concentration was 1.5 times higher than $PM_{2.5}$ and 1.85 times higher than $PM_1$. Ratio of $(PM_{10}-PM_{2.5})/PM_{2.5}$ had a maximum value of 1.49 with an averaged 0.5 and one of $(PM_{2.5}-PM_1)/PM_1$ had a maximum value of 0.4 with an averaged 0.25. $PM_{10}\;and\;PM_{2.5}$ concentrations were largely influenced by particles smaller than $2.5{\mu}m\;and\;1{\mu}m$ particle sizes, respectively. During the dust event from the afternoon of March 10 until 1200 LST, March 14, $PM_{10},\;PM_{2.5}\;and\;PM_1$ concentrations reached $343.53{\mu}g/m^3,\;105{\mu}g/m^3\;and\;60{\mu}g/m^3$, indicating the $PM_{10}$ concentration being 3.3 times higher than $PM_{2.5}$ and 5.97 times higher than $PM_1$. Ratio of $(PM_{10}-PM_{2.5})/PM_{2.5}$ had a maximum value of 7.82 with an averaged 3.5 and one of $(PM_{2.5}-PM_1)/PM_1$, had a maximum value of 2.8 with an averaged 1.5, showing $PM_{10}\;and\;PM_{2.5}$ concentrations largely influenced by particles greater than $2.5{\mu}m\;and\;1{\mu}m$ particle sizes, respectively. After the dust event, the most of PM concentrations became below $100{\mu}g/m^3$, except of 0900LST, March 15, showing the gradual decrease of their concentrations. Ratio of $(PM_{10}-PM_{2.5})/PM_{2.5}$ had a maximum value of 3.75 with an averaged 1.6 and one of $(PM_{2.5}-PM_1)/PM_1$ had a maximum value of 1.5 with an averaged 0.8, showing the $PM_{10}$ concentration largely influenced by corse particles than $2.5{\mu}m$ and the $PM_{2.5}$ by fine particles smaller than $1{\mu}m$, respectively. Before the dust event, correlation coefficients between $PM_{10},\;PM_{2.5}\;and\;PM_1$, were 0.89, 0.99 and 0.82, respectively, and during the dust event, the coefficients were 0.71, 0.94 and 0.44. After the dust event, the coefficients were 0.90, 0.99 and 0.85. For whole period, the coefficients were 0.54, 0.95 and 0.28, respectively.

• Journal of Bio-Environment Control
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• v.21 no.3
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• pp.271-275
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• 2012

The average annual and winter ambient air temperatures in Korea have risen by $0.7^{\circ}C$ and $1.4^{\circ}C$, respectively, during the last 30 years. The continuous rise in temperature presents a challenge in growing certain horticultural crops. Chinese cabbage, one most important cool season crop, may well be used as a model to study the influence of climate change on plant growth, because it is more adversely affected by elevated temperatures than warm season crops. This study examined the influence of transplanting time, nitrogen fertilizer level and climate parameters, including air temperature and growing degree days (GDD), on the performance of a Chinese cabbage cultivar (Chunkwang) during the spring growing season to estimate crop yield under the unfavorable environmental conditions. The chinese cabbage plants were transplanted from Apr. 8 to May 13, 2011 when 3~4 leaves were occurred, at internals of 7 days and cultivated with 3 levels of nitrogen fertilization. The data from plants transplanted on Apr. 22 and 29, 2012 were used for the prediction of yield as affected by planting date and nitrogen fertilization for spring production. In our study, plant dry weight was higher when the seedlings were transplanted on 15th (168 g) than on 22nd (139 g) of April. There was no significant difference in the yield when plants were grown with different levels of nitrogen fertilizer. The values of correlation coefficient ($R^2$) between GDD and number of leaves, and between GDD and dry weight of the above-ground plant parts were 0.9818 and 0.9584, respectively. Nitrogen fertilizer did not provide a good correlation with the plant growth. Results of this study suggest that the GDD values can be used as a good indicator in predicting the top biomass yield of Chinese cabbage.

• The korean journal of orthodontics
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• v.28 no.5 s.70
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• pp.825-838
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• 1998

The purpose of this study was to evaluate the differences of soft tissue profile changes between the growing patients and the adult who had passed the growth peak, in orthodontic treatment with four premolar extractions. The results which was taken by correlating the soft tissue changes with hard tissue changes, lip thickness, molar relationship and arch length discrepancy in both groups was like the followings. 1. Significant hard tissue changes were decrease of VIs, VIi, UlPP, LlMP, HIi and increase of HPog'in adults and decrease of VIs, VIi and increase of VA, VPog'and all the vertical measurements in adolescents. 2. Significant soft tissue changes were decrease of VLs, VLi, and VILS in adults and increase of VSn, VSLS, VLs, VPog' and almost all vertical measurements in adolescents, and ${\Delta}LsE,\;{\Denta}LiE$ in adults and ${\Delta}LsE,\;{\Denta}LiE,\;{\Delta}LiSP\;and\;{\Delta}Mang$ was also significant 3. Correlation coefficient between ${\Delta}VIs\;and\;{\Delta}VLs$ was the greatest in adults and the next was ${\Delta}Ii/{\Delta}Li,\;{\Delta}Ii/{\Delta}ILS,\;{\Delta}ID/{\Delta}Li\;and\;{\Delta}ID/{\Delta}ILS$. In contrast all the vertical and horizontal measurements of hard and soft tissue in adolescents showed statistically significant corerrlation. 4. There were differences in correlation between soft tissue changes and incisor inclination and retraction at both groups, but the lower lip, nasolabial angle and mentolabial angle were commonly less influenced by the hard tissue changes in both groups. 5. The thinner the upper lip was, the more the ${\Delta}LsSP$ was in both groups, and the thinner the lower lip was, the more the ${\Delta}LiE\;and\;{\Denta}LiSP$ was in adolescents. 6. Molar relationship didn't influence the soft tissue profile changes. 7. Arch length discrepancy didn't influence the soft tissue profile changes.

• The Journal of Korean Society for School & Community Health Education
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• v.3
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• pp.35-58
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• 2002

This research attempted to investigate the real state of adolescent smoking and drinking, and to study how stress influences on smoking and drinking of high school students. This data was collected from 837 first and second grade students in a vocational high school in Go-yang city, Gyeonggi province. Data analysis consisted of frequency, percentage, Chi-square, T-test, step-wise regression analysis, using SPSSWIN. The results of analysis were as follows: First, 51.7% of the students have never smoked, while 48.3% have experienced smoking. Most students started smoking in the second year of the middle school, though 17.6% of the smokers already started in the elementary school. The strongest motive of initial smoking was curiosity, next the inducement of friends, and 10.9% of them smoked to get rid of stress. Their favorite place for smoking was in the order of the entertainment centers, schools, and private academies. They personally purchased cigarettes mostly at the store. Most of them smoked less than 5 cigarettes a day, but 3.7% smoked more than a pack of cigarettes a day, usually with friends rather than alone. Second, the ratio of drinking was relatively high 78.1%, and their initial drinking experience was most frequent at the third year of the middle school. The initial motive of drinking was mostly curiosity and the inducement of friends, but 10.7% of them started drinking to reduce stress and anxiety. The places for buying alcohol and drinking were bars or restaurants. The ratio of habitual drinking was 45.1%, and the ratio of irregular drinking was 53.3%. 1.8% of the drinking students enjoyed drinking everyday. The amount of drinking varied from half a bottle to two bottles of Soju, and the drinking problem was serious to see that 11% of them drank more than two bottles at a time. Because 84.4% drank in groups with friends, a thorough and systematic supervision and education of the peer group drinking is essential. Third, as for the relationship between personal matters and smoking, it was found that there was a positive relation between smoking and sex, but there was no correlation between smoking and school years. Adolescent smoking was also related with scholastic achievement, the number of friends, and the existence of parents. Fourth, as for the relationship between personal matters and drinking, it was found that there was no correlation between drinking and sex, but there was a positive relation between drinking and school years. Fifth, the average index of stress was students themselves(2.58), school life(2.53), family life(2.19), friends(2.00), and the total index of stress was 2.33. Sixth, there appeared a marginal negative correlation between stress and 'drinking and smoking' in Pearson coefficient of correlation r to see the influence of stress on smoking and drinking. The difference of the average index of stress according to smoking and drinking bears meaningful difference for all students, smokers and non-smokers, drinkers and abstainers in students themselves, school life, family life, friends, and total stress. Smoking has an effect on family life most, school life next, and drinking has an effect on school life most, family life next, with the explanation power of 11% and 9% respectively, in a regression analysis to analyze the factors influencing on smoking and drinking among the factors of stress.

• Korean Journal of Occupational Health Nursing
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• v.11 no.1
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• pp.13-30
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• 2002

Industrial shift workers feels suffer mental stresses which are caused by unfamiliar day sleep, noisy environment, sleeping disorder by bright light, unusual contacts with family, difficulty in meeting with friends or having formal social meetings and other social limitations such as the use of transportation. Such stresses influence health of the workers negatively. Thus the health promotion policy for shift workers should be made considering the workers' ways of living and shift work specially. This study attempted to provide basic information for development of the health promotion program for industrial shift workers by examining predictive factors influencing health promotion behaviors of those workers. In designing the study, three power generation plants located in Pusan and south Kyungsang province were randomly selected and therefrom 280 workers at central control, boiler and turbine rooms and environmental chemistry parts whose processes require shift works were sampled as subjects of the study. Data were collected two times from September 17 to October 8, 1999 using questionnaires with helps of safety and health managers of the plants. The questionnaires were distributed through mails or direct visits. Means for the study included the measurement tool of health promotion behavior provided by Park(1995), the tool of self-efficacy measurement by Suh(1995), the tool of internal locus of control measurement by Oh(1987), the measurement tool of perceived health state by Park(1995) and the tool of social support measurement by Paek(1995). The collected data were analyzed using SPSS program. Controlling factors of the subjects were evaluated in terms of frequency and percentage ratio Perceived factors and health promotion behaviors of the subjects were done so in terms of mean and standard deviation, and average mark and standard deviation, respectively. Relations between controlling and perceived factors were analyzed using t-test and ANOVA and those between perceived factors and the performance of health promotion behaviors, using Pearson's Correlation Coefficient. The performance of health promotion behaviors was tested using t-test, ANOVA and post multi-comparison (Scheffe test). Predictive factors of health promotion behavior were examined through the Stepwise Multiple Regression Analysis. Results of the study are summarized as follows. 1. The performance of health promotion behaviors by the subjects was evaluated as having the value of mean, $161.27{\pm}26.73$ points(min.:60, max.:240) and average mark, $2.68{\pm}0.44$ points(min.:1, max.:4). When the performance was analyzed according to related aspects, it showed the highest level in harmonious relation with average mark, $3.15{\pm}.56$ points, followed by hygienic life($3.03{\pm}.55$), self-realization ($2.84{\pm}.55$), emotional support($2.73{\pm}.61$), regular meals($2.71{\pm}.76$), self-control($2.62{\pm}.63$), health diet($2.62{\pm}.56$), rest and sleep($2.60{\pm}.59$), exercise and activity($2.53{\pm}.57$), diet control($2.52{\pm}.56$) and special health management($2.06{\pm}.65$). 2. In relations between perceived factors of the subjects(self-efficacy, internal locus of control, perceived health state) and the performance of health promotion behaviors, the performance was found having significantly pure relations with self-efficacy (r=.524, P=.000), internal locus of control (r=.225, P=.000) and perceived health state(r=.244, P=.000). The higher each evaluated point of the three factors was, the higher the performance was in level. 3. When relations between the controlling factors(demography-based social, health-related, job-related and human relations characteristics) and the performance of health promotion behaviors were analyzed, the performance showed significant differences according to marital status (t=2.09, P= .03), religion(F=3.93, P= .00) and participation in religious activities (F=8.10, P= .00) out of demography-based characteristics, medical examination results (F=7.20, P= .00) and methods of the collection of health knowledge and information(F=3.41, P= .01) and methods of desired health education(F=3.41, P= .01) out of health-related characteristics, detrimental factors perception(F=4.49, P= .01) and job satisfaction(F=8.41, P= .00) out of job-related characteristics and social support(F=14.69, P= .00) out of human relations characteristics. 4. The factor which is a variable predicting best the performance of health promotion behaviors by the subjects was the self-efficacy accounting for 27.4% of the prediction, followed by participation in religious activities, social support, job satisfaction, received health state and internal locus of control in order all of which totally account for 41.0%. In conclusion, the predictive factor which most influence the performance of health promotion behaviors by shift workers was self-efficacy. To promote the sense, therefore, it is necessary to develop the nursing intervention program considering predictive factors as variables identified in this study. Further industrial nurses should play their roles actively to help shift workers increase their capability of self-management of health.

• The Korean Journal of Malacology
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• v.25 no.2
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• pp.161-171
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• 2009

The present study was performed to describe the influence of water temperature and salinity on filtration rates of the venus clam, Gomphina veneriformis, a suspension-feeding (filter-feeding) bivalve species. The calmswere collected from the eastern coastal area of Sokcho, Gangneung and Jumunjin at Kangwon-do, Korea, during December 2006 and May 2007. Isochrysis galbana (KMCC H-002) cells as food organisms were indoor-cultured by f/2 medium, and were used to measure the filtration rate of clam. Filtration rates of clam were measured by indirect method. Cell concentration of food organisms were determined by direct counting cells used the hemacytometer under the light microscope. The filtration rates of clams by water temperature sharply increased with temperatures up to $15^{\circ}C$ as optimum temperature and above this temperature, the filtration rates decreased exponentially. Venus clams showed very low filtration rates at low salinity (10-15 psu) and maximum values at high salinity (30-35 psu). Regardless of water temperature and salt change, 2-year class clams showed high filtration rates, but low in 4-year-class. Polynomial regression curves with water temperature were shifted to the left in low temperature region. Thermal coefficient $Q_{10}$ values showed much higher values at low temperature range than at high temperature range, too. These results indicate that the venus clam is more sensitive in cold water. Polynomial regression curves with salinity were shifted to the right in high saline region. According to this study, the venus clam Gomphina veneriformis, subtidal filter-feeding bivalve, was the stenothermal organism, inhabited mainly in low temperature and the stenohaline, in high saline waters.

• The Korean Journal of Malacology
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• v.24 no.3
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• pp.175-188
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• 2008

This study was performed to describe the influence of water temperature and salinity on the filtration rate of the hard clam, Meretrix petechialis. The filtration rates of hard clams showed significant differences depending on both water temperature and age group (two-way ANOVA, p < 0.001). The filtration rate of all the hard clams, aged from 1 to 4 years, was generally reduced in low temperature range ( $5-15^{\circ}C$). As the water temperature increased, the filtration rate increased exponentially. The filtration rate was relatively high in $20-30^{\circ}C$ water temperature range, but rapidly decreased again at around $35^{\circ}C$. Variations in the data for filtration rates of hard clams, relative to age and changing water temperature, were used to determine the temperature coefficient $Q_{10}$ in each water temperature range. In $5-15^{\circ}C$ temperature range, every age group showed the highest $Q_{10}$ figure. It was found that on the whole, the higher the water temperature was, the lower the number of $Q_{10}$ was. Regardless of age, the number of $Q_{10}$ was higher in the lower water temperature range. In $25-35^{\circ}C$ temperature range, the number of $Q_{10}$ was less than 1.00 in all age groups, implying that this is the range in which the filtration rate decreased. Variations in the filtration rate also showed very clear differences (two-way ANOVA, p < 0.001) according to changing salinity and age. All the age groups, from 1 to 4 year olds, showed low filtration rates at both low salinity (10-15 psu) and high salinity (40 psu). The highest filtration rate was recorded at 30 psu, and relatively high filtration rates were found around 30 psu. However, the Student-Newman-Keuls post hoc multiple comparison test found that the hard clams in the 1-year group showed high filtration rates in a relatively narrower salinity range compared to those in the 2, 3, and 4 year groups. In other words, hard clams in the 2, 3, and 4 year groups showed high filtration rates at higher levels of salinity.

• Korean Journal of Adult Nursing
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• v.12 no.2
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• pp.184-195
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• 2000

It has been believed that cancer is an omnious factor threatening the future and life itself. Patients having the disease experience anxiety, fear, feeling of weakness, depression and feelings of uncertainty and hopelessness. Most cancer patients, however, have expectations of possible recovery and a better future, very different from the patients who feel hopeless. Therefore. hope allows people to respond effectively to the fatal disease they have and prevents them from detoriorating physically and spiritually, positively influencing their survival, response to treatment and sense of security. Studies previously performed showed that hope is positively correlated with social and family supports, self-esteem, spiritual well-being, responsive action, health promotion behavior and quality of life. Thus, the study attempted to provide basic information on nursing cancer patients by investigating their levels of hope and determining predictive factors which influence hope. For the study 200 cancer patients in two university hospitals located in Pusan were sampled as subjects. Data were collected for twenty nine days from Feburary 1, 1999 to March 1. Instrumets for the study included 10 items from the self-esteem scale by Rosenberg (1965), 39 hope measurements by Kim and Lee(1965), 16 of the social support scale by Tae(1986) and 16 of the general characteristics scale, all of which totaled 81 items. The data were analyzed using the SPSS program. General characteristics of the investigated based on numbers and percentage. Hope, self-esteem and social support were analyzed using means, minimum, maximum and standard deviation. Relations among the foregoing three factors were analyzed using Pearson' correlation coefficient. Levels of hope in cancer patients were determined using t-test, ANOVA and Scheffe test. Predictive factors influencing hope were investigated using multiple stepwise regression analysis. Results of the study are summarized as follows: 1. An average level of hope was $185.55{\pm}23.39$ points(96 min. and 234 max.) 2. Levels of hope showed a significant difference among them according to sex (t=-3.69, P=.000), age(F=4.714, P=.000), job(F=3.247, P=.008), monthly income (F=6.113, P=.003), treatment charge (F=3.796, P=.011), supportive resources (F=10.554, P=.000), diagnosis(F=2.287, P=.029), perceived health status(F=22.184, P=.000), level of pain(F=3.334, P=.021), religion (F=4.911, P=.001) and religion's effect in life (F=11.706, P=.000), 3. For the subjects, self-esteem and social support were $38.32{\pm}7.21$(13 min, and 50 max.) and $52.97{\pm}8.49$points(28 min, 80 max.). Concerning social support, average levels of family support and medical support were found $35.95{\pm}6.05$(18 min, and 40 max) and $27.02{\pm}4.99$ points(20 min and 40 max). The hope the cancer patients showed significant correlations with self-esteem (r=.588, P=.000), family support(r=.224, p=.001) and medical support(r=.221, P=.002). 4. The five variables related to hope (self-esteem, religion's effect in life, perceived health status, social support and age) accounted for 54.2 percent of the hope level; especially, self-esteem was the highest at 34.6%. As shown in the above results, predictive factors which most influence hope in cancer patients were self-esteem and religion's effect of life. Therefore, nursing interventions to increase self-esteem should be developed. Regarding religion's effects, studies on spiritual aspects should be carried out in a way that contributes to promotion of hope.