• Journal of the Korean Wood Science and Technology
• /
• v.36 no.1
• /
• pp.30-35
• /
• 2008

Degradation of mechanical properties of fire-killed Korean red pine has been investigated after death in 5 years period. Impact bending absorbed energy was the most sensitive property by elapsed time after forest fire. It is an indication of incipient decay of the wood and can be useful indicator to monitor any change of mechanical property of fire-killed tree after death. Degradation of mechanical properties was more pronounced in sapwood than heartwood. Impact bending absorbed energy was more reduced than any other properties in both sapwood and heartwood, while compressive strength was least impacted by elapsed time after forest fire. It is recommended that the fire-killed Korean red pine can be harvested in one year after the fire for industrial uses by considering decay and consequent changes of mechanical properties.

• Proceedings of the KSR Conference
• /
• 2011.05a
• /
• pp.1636-1641
• /
• 2011

Typically Korea Railroad is executing the limited inspection and general inspection about passenger car by mileage and the time elapsed.(ex. one year, two years) These types of inspection system continue from the beginning of the railroad operation of the steam locomotive age to present. According to the rolling stocks modernized and improved, mileage and the time elapsed for periodical inspection has been expanded but the basic maintainability system of rolling stocks is not that different from the past. This fact needs verification that modern inspection method is right from various fields. In this paper, we analyze the data that we get the maintenance record from Korea railroad company about periodical inspection and failure. Next to considering the correlation of periodical inspection with failure based on analyzed data for watching periodical inspection effects. And we desire to need efficient rolling stock maintenance system better than fixed periodical inspection.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.47 no.3
• /
• pp.197-208
• /
• 2021

Objectives: The purpose of this retrospective study was to evaluate the variables associated with length of stay (LOS), hospital costs, intensive care unit (ICU) use, and treatment outcomes in patients hospitalized for maxillofacial infections at a tertiary medical center in South Korea. Materials and Methods: A retrospective chart review was conducted for patients admitted for treatment of maxillofacial infections at Dankook University Hospital from January 1, 2011 through September 30, 2020. A total of 390 patient charts were reviewed and included in the final statistical analyses. Results: Average LOS and hospital bill per patient of this study was 11.47 days, and ₩4,710,017.25 ($4,216.67), respectively. Of the 390 subjects, 97.3% were discharged routinely following complete recovery, 1.0% expired following treatment, and 0.8% were transferred to another hospital. In multivariate linear regression analyses to determine variables associated with LOS, admission year, infection side, Flynn score, deep neck infection, cardiovascular disease, admission C-reactive protein (CRP) and glucose levels, number and length of surgical interventions, tracheostomy, time elapsed from admission to first surgery, and length of ICU stay accounted for 85.8% of the variation. With regard to the total hospital bill, significantly associated variables were age, type of insurance, Flynn score, number of comorbidities, admission CRP, white blood cell, and glucose levels, admission temperature, peak temperature, surgical intervention, the length, type, and location of surgery, tracheostomy, time elapsed from admission to first surgery, and length of ICU use, which accounted for 90.4% of the variation. Age and ICU use were the only variables significantly associated with unfavorable discharge outcomes in multivariate logistic regression analysis. Conclusion: For successful and cost-effective management of maxillofacial infections, clinicians to be vigilant about the decision to admit patients with maxillofacial infections, perform appropriate surgery at an adequate time, and admit them to the ICU.

• Journal of Ecology and Environment
• /
• v.41 no.9
• /
• pp.246-255
• /
• 2017

Background: The aim of this study was to examine the resource allocation among the organs and the leaf morphology of Polygonatum humile. The data were collected from June 2014 to May 2015 in a natural P. humile stand of a temperate forest gap. Results: The dry weight of new rhizome ($R_0$) sharply decreased to the time of new shoot sprouting in next year and was constant for 2 ~ 3 years. However, dry weight of root on $R_0$ increased to the end of growth season and, thereafter, decreased slowly along the time elapsed. The correlation coefficients between the rhizome and the leaf sizes were 0.5 for the last year's rhizome ($R_1$) and 0.6 for $R_0$ and were significant at 0.1% level for $R_0$. The increase of one leaf a plant led to increase of the total leaf area, total leaf weight, and stem length. Moreover, the organ sizes' differences between two plants of the one leaf difference were almost significant at 1% level. In 11-leaf plant, the leaf length/width ratio and specific lea area increased to the second, relative leaf area to the fourth and relative leaf dry weight to the fifth, and thereafter, decreased to the last leaf. The differences in the values of these four parameters between two leaves on a stem were almost significant at 5% level. Conclusion: P. humile examined showed the close relationships between the last year's rhizome or this year's one and the shoot system (leaf and stem) sizes. The leaf number a shoot greatly influenced specific leaf area. P. humile's leaf might showed diverse morphology with leaf rank on a stem in a forest gap environment.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.28 no.9
• /
• pp.35-44
• /
• 2014

This study was to secure the safety of poor appearance distribution concrete poles effectively and to reduce the replacement costs of them by developing a soundness evaluation index. The researcher of this study investigated poor appearance types of concrete pole, collected 53 of test samples, and tested pole strength. As a result of strength test, only 17 percent of poor appearance concrete poles were below 2.0 of safety factor spec. As results of multiple regression analysis, it is verified that surface air void, horizontal crack, net-shaped crack, elapsed year, vertical crack, and deterioration in concrete compressive strength have statistically negative effects on safety factor of concrete poles in a significant level. The researcher set up a soundness evaluation index by using multiple regression equation, and suggested that poor appearance concrete poles should be replaced or reinforced only in case of soundness evaluation score of 150 or above.

• Journal of Korean Society of Transportation
• /
• v.11 no.2
• /
• pp.45-62
• /
• 1993

The major objective of this study is to analyze the differences between operating costs of teleconferencing and alternative transportation modes for the conference in major compaines. Alternative transportation modes include road, rail, and air transportation mode. A case study is conducted using the data gathered for Pohang Steel Coperations. The main results are: (1) the operating cost of the teleconferencing is cheaper than operating cost of transportation modes when the number of teleconferencing are over 12 frequencs, and the number of person are over 15. Results reveal that teleconferencing turns out to be effective means of conference. (2) the amount of differences of operating costs on teleconsferencing and transportation modes gets higher according to the time elapsed. In particular, when teleconferencing cost is compared to operating cost of road transportation, it is found that the cost saving of 2.75 billion won in year 2001 can be realized.

• Journal of Chest Surgery
• /
• v.16 no.4
• /
• pp.506-510
• /
• 1983

Valve dysfunction can be caused by thickening or contraction of a fibrous sheath covering a cusp of a porcine bioprosthesis, but this is uncommon. This complication appears to more frequent in other bioprostheses, such as fascia late valves and homografts, in which fibrous sheaths seems to grow more rapidly. rapidly. Thus the slow and limited growth of fibrous sheath in porcine bioprostheses is advantageous in this respect. Recently, we experienced a case of valve dysfunction caused by fibrous tissue overgrowth on Hancock mitral xenograft in 45 year old female. 3.5 years ago, the patient was received valve replacement due to mitral stenoinsufficiency. But since 2.5 years elapsed after operation, she has complained of generalized edema and dyspnea, and their symptoms were aggravated progressively. So reoperation was performed under the diagnosis as valve dysfunction of mitral xenograft and newly developed tricuspid insufficiency. Her postoperative courses were good.

• Proceedings of the Korean Society of Agricultural Engineers Conference
• /
• 2005.10a
• /
• pp.330-335
• /
• 2005

This study was performed for the analysis of the variation characteristics on riverbed according to the arrangement of stream. It was monitored of the variation progress of riverbed dependent on the elapsed time after the arrangement and It was studied that the hydraulic adjustment of the riverbed caused by the variation of the riverbed. The large amount of deposit just after the construction in which the riverbed was arranged to natural form was come from the reduction of flow rate by the installed artificialities such as weirs and stone weirs and by the stones or the concrete blocks attached to the stream sides of riverbanks. This phenomenon was well consistent with the usual characteristics that the accumulation is induced on upper stream of hydraulic artificialities and the erosion is induced on down stream of hydraulic artificialities. The large reduction of the deposit 1 year later after the construction showed that the riverbed eroded considerably because of the recovery of flow amount and the rise of flow rate.

• Korea Real Estate Review
• /
• v.28 no.1
• /
• pp.91-104
• /
• 2018

In this study, the occurrence and degree of herding behavior as a market participant behavior in a housing market were analyzed. For the analysis method, the actual sales price was applied in the CSAD (Cross-sectional Absolute Deviation) model, which has been used the most of late for herding behavior analysis. For the analysis contents, these were subdivided into region, elapsed year, size, and market condition to analyze the regionality and the internal and external factors. For the study results, first, there was no herding behavior in the entire region of Seoul. By region, herding behavior occurred in the downtown, southeast, and northwest regions, which coincided with the results of the precedent study (Ngene et al., 2017). Second, in the market analysis by elapsed year, herding behavior was captured in dilapidated dwellings. By size, herding behavior was observed in small-scale ($60m^2$ or less) apartments and in $85m^2$ or higher and less than $102m^2$ national housing units. Third, during the time of the global financial crisis, herding behavior was not observed in all the regions, whereas when the market situations were in a boom cycle, it was observed in the northwest region. These results suggest that there is a difference from the stock market, where in a period of recession, herding behavior occurs intensively with the expanding fear of incurring losses. This study is significant in that it analyzed the market participant behaviors in the behavioral economic aspects to better understand the abnormal phenomenon in a housing market, and in that it additionally provides a psychological factor - market participant behavior - in market analysis.

• The Journal of the Korean life insurance medical association
• /
• v.1 no.1
• /
• pp.140-147
• /
• 1984

We've reviewed 5,067 cases of claims by death that had occured for about 5 years from January, 1979 to October, 1983. As a result, We came to following conclusions; First, the greater part of deaths above mentioned were due to the Disease of Adult such as the Malignant neoplasm(18.4%), a Heart disease(10.4%), Liver cirrhosis(9.1%) and the Cerebrovascular disease(7.6%) as well as Accidental Death(26.5%), which were occupied by 72% of the whole. Second, classifying them by medical examination or non-medical, deaths in case of non-medical examination showed 80.8% of the. whole. And for age, sections ranging from 40 to 49 and from 30 to 39 took the overwhelming portions by 36.9% and 29.8% respectively, both of which showed 66.7% of the whole. Third, for the period elapsed, deaths within 1 year from the entrance showed 21.3% and that from 1 years to under 2 years, 19.9%. Thus the rate of early death under 2 years stood for 41.2% of the whole. Fourth, for occupation of the insureds, commerce occupied 20.4%, company employees 14.4%, agriculture 13.3%. These three categories marked 48.8% of the whole. From this, it appeared that the accidental death rate of the insured with the risky occupation was much greater than orthers.