• Asian Journal of Turfgrass Science
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• v.19 no.2
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• pp.131-140
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• 2005

This study was conducted to compare cold tolerances and growth rates of 5 basic species, commercial lines, and breeding lines of zoysiagrass. Total 41 zoysiagrasses were tested at the northern part (Jeokseong-myeon) and the middle part (Cheonan) of South Korea. Cold tolerance (survival rate during winter), growth rate, green-up speed, and density data were collected visually. Four types of zoysiagrasses (Z. matrella, Z. tenuifolia, USm, and S4M2) with genetic characteristics of Z. matrella died during winter cold, while the others survived. Midium leaf type zoysiagrasses, such as Anyang1, Samdeock1, Anyang2, SJ21, and Pyeongdong, with genetic characteristics of both Z. sinica and Z. macrostachya showed vigorous growth rate one year after planting at the northern part (Jeokseong-myeon). Twenty nine ($70.7\%$) zoysiagrasses showed vigorous growth rate, but the other twelve ($29.3\%$) zoysiagrasses died by cold and drought condition at the middle (Cheonan) part of S. Korea. Anyang2, AJ9-7, Samdeock1, Samdeock2, Samdeock3, and Zenith-C showed vigorous growth rate even though cold and drought environmental condition were artificially provided at these region. But, SJ2-19, NSm, 88Mey, 88Mey-7S, 88Mey-9S, SJ2l-10, ASm, and DBm which did not die at the northern part, showed serious injury at the middle part of S. korea. From this results, we can conclude that drought is as important factor as low temperature for zoysiagrasses during winter.

• Journal of agricultural medicine and community health
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• v.9 no.1
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• pp.46-55
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• 1984

The socio-psychiatric study and personality analysis by Minnesota Multiphasic Personality Inventory on attempted suicides with drug intoxication in Seonsan-Gun and Cheongdo-Gun of Kyoungsang buk-Do was attempted to identify overall picture of attempted suicides and to detect some characteristics of personality. The total of 93 suicide attempted cases which were brought to the local clinics for the past 3 years from February, 1981 to February,1984 were sampled among them. The socio-psychiatric study and MMPI were performed with 45 attempters possible to be interviewed. The personalities of a group which answered "Still have the desire occasionally" or "Don't know about the present attitude toward suicide was compared with those of the other group who answered "Will not do it agagin". The results were as follows; 1) The sex ratio of the total attempters (93 cases) were 138.5. The highest rate by age group was found in the 3rd decade to be 27 cases. On the other hand, the sex ratio of interviewed cases were 136.8 and the highest rate was found in the age group of 50-59. 2) For the common characteristics of majority other than sex, 55.7% of cases were graduated primary school, and 62.2% were engaged in agriculture. 3) Except the fact that more of the attempted suicides happened during summer, there were no seasonal variation among other seasons. 4) The places selected for the attempted suicides were the houses in majority of cases (98%). Most of cases (53.3%) were found immediately after the attempt and 24.4% within one hour. For the poison taken, 86.7 took a sort of herbicides or insecticides, 55.6% were admitted to local clinics for only one day and 20% for two days. 5) The most common precipitating factors of the attempted suicides were family trouble and financial poverty. 6) The psychodynamic motives of the attempters were impulsive hostility(35.6%), abandonment(33.3%), guilt feeling (11.1%), manipulation and attention seeking (8.9%) and others. 7) In regard to their present attitude toward suicide, 29 cases (64.4%) expressed that they would never do such an act again, 37.8% of cases expressed that they really wanted to die at the time when they attempted. 8) The Psychopathic deviate, Paranoia, Depression, Schizophrenia scores were significantly higher in the attempters group who answered "Don't know" or "Possibly" for the question of "Will you attempt suicide again?" Than the group who answered" will not do it again".

• Korean Journal of Food Science and Technology
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• v.37 no.5
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• pp.757-762
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• 2005

Characteristics of cereals prepared by extrusion-cooking and freeze-drying were compared. Parameters used were water solubility index (WSI), water absorption index (WAI), paste viscosity, and sterilization. Variables for extrusion process were barrel temperature at die section (70, 90, and $110^{\circ}C$) and moisture content (25 and 30%). WAI and WSI of extruded cereals were higher, whereas trough, breakdown, and final viscosity were lower than those of raw and freeze-dried cereals. Plate counting revealed no microbes in extruded cereals, whereas microbe colony was observed in freeze-dried cereals. Extrusion-cooking at low temperature resulted in better sterilization of microbes than freeze-drying for preparation of instant cereal drinks.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.2
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• pp.593-601
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• 2021

The axial fan is an element of a blower used for ventilation in various industrial fields. Many studies on aerodynamic performance have been conducted to assess axial fans using fluid dynamics. The subject was a large axial fan size, 1800 mm in diameter with 100 horsepower. The blower's axial fan consisted of blades, hubs, hub caps, and bosses are important components. The blade design has a great influence on the aerodynamic performance. 3D point data is extracted using an aerodynamic performance prediction program, and a 3D modeling shape is generated. The blades and hubs, which are important components, can be easily modified if processed by cutting owing to the environment in which blades and hubs are manufactured through die casting or gravity casting. In this study, the structural safety of components and the analysis results of weak areas at the rated operating speed of the axial fan were verified using the maximum stress and safety factor. The tip clearance reflected in the design was the rotation of the blade. To check whether there is interference with other components, the displacement result was derived to verify the structural safety of the axial fan.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.34 no.1
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• pp.1-7
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• 2024

β-Ga₂O₃ is a material with a wide band gap of ~4.8 eV and a high breakdown-voltage of 8 MV/cm, and is attracting much attention in the field of power device applications. In addition, compared to representative WBG semiconductor materials such as SiC, GaN and Diamond, it has the advantage of enabling single crystal growth with high growth rate and low manufacturing cost [1-4]. In this study, we succeeded in growing a 10 mm thick β-Ga₂O₃ single crystal doped with 0.3 mol% SnO₂ through the EFG (Edge-defined Film-fed Growth) method using multi-slit structure. The growth direction and growth plane were set to [010]/(010), respectively, and the growth speed was about 12 mm/h. The grown β-Ga₂O₃ single crystal was cut into various crystal planes (010, 001, 100, ${\bar{2}}01$) and surface processed. The processed samples were compared for characteristics according to crystal plane through analysis such as XRD, UV/VIS/NIR/Spec., Mercury Probe, AFM and Etching. This research is expected to contribute to the development of power semiconductor technology in high-voltage and high-temperature applications, and selecting a substrate with better characteristics will play an important role in improving device performance and reliability.

• Journal of the Microelectronics and Packaging Society
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• v.17 no.4
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• pp.49-60
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• 2010

Semiconductor packages are increasingly moving toward miniaturization, lighter and high performance. Futhermore, packages become thinner. Thin packages will generate serious reliability problems such as warpage, crack and other failures. Reliability problems are mainly caused by the CTE mismatch of various package materials. Therefore, proper selection of the package materials and geometrical optimization is very important for controlling the warpage and the stress of the package. In this study, we investigated the characteristics of the warpage and the stress of several packages currently used in mobile devices such as CABGA, fcSCP, SCSP, and MCP. Warpage and stress distribution are analyzed by the finite element simulation. Key material properties which affect the warpage of package are investigated such as the elastic moduli, CTEs of EMC molding and the substrate. Geometrical effects are also investigated including the thickness or size of EMC molding, silicon die and substrate. The simulation results indicate that the most influential factors on warpage are EMC molding thickness, CTE of EMC, elastic modulus of the substrate. Simulation results show that warpage is the largest for SCSP. In order to reduce the warpage, DOE optimization is performed, and the optimization results show that warpage of SCSP becomes $10{\mu}m$.

• Journal of the Korean Institute of Gas
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• v.4 no.1 s.9
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• pp.26-32
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• 2000

The fretting wear corrosion characteristics between the SM20C and the SM20C, the YBsC3 and the STC4H was experimented by using radical type friction experimental device under the corrosion environment of atmosphere, neutral solution, acid solution and chemical factors of the sea water. The affection of underground water that affect fretting wear corrosion of the SM20C which is moving specimen was more sensitive at the STC4H and more insensible at the YBsC3. The affection of underground water that affect fretting wear corrosion of the STC4H was less, but in the $0.5\%\;H_2SO_4$ and $0.5\%\;HNO_3$ solutions the fretting wear corrosion of the STC4H was more large. The fretting wear corrosion of the SM20C which is moving specimen in the underground water was less than in the $3.5\%\;NaCl$, $0.5\%\;H_2SO_4$ and $0.5\%\;HNO_3$ solutions. As time passed, the fretting wear corrosion is increased in the $HNO_3$ solution and dull in the $0.5\%\;H_2SO_4$ solution.

• Korea journal of population studies
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• v.24 no.1
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• pp.5-40
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• 2001

We have approached this study on the basis of population and family changes. We have selected two suburban and two general rural areas for this research. The suburban rural areas are located next to Chungju City, which is the biggest city in Chungbuk Province, and the residents are able to commute to Chungju. The general rural areas are located in Boeun Gun, which is a typical agricultural county in Chungbuk Province. We have conducted two round surveys at the research areas: 1995-1996 for the first round and 1999-2000 for the second round surveys. Since the surveys were completed ones interviewed by enumerators, we have used the survey data directly for the analysis by year and region. The population structure by age and sex in general rural areas is shaped as a reverse triangle, which is becoming more serious because of the continuing emigration of young generation. Most of the young generation moves to the urban areas and their old parents only are left in their hometown, rural areas. When the parents become old and die, the number of households in the areas decreases rapidly. If there are no more new family formations, therefore, the rural society itself would cease to exist in near future. However, the situation of suburban rural areas was a different case. Although the rural young generation has moved to urban areas, other young age groups have moved into the areas with their small enterprises and for the low living costs. The original residents become older and the young age groups are replaced with the new immigrants continuously. Therefore, the traditional agricultural society will be replaced with a non-agricultural society, which will have more characteristics of urban areas.

• Journal of agricultural medicine and community health
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• v.24 no.2
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• pp.369-385
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• 1999

This is carried out to study on the general consciousness for medical ethics of Korean local and hospital clinicians from March to May, 1999. The subjects are 288 respondents out of 1,500 those who selected by systemic random sampling method from the list of physicians published on 1997. An adequate questionnaire with 21 questions made by author was distributed through mail for those. The characteristics of respondents are as follows. Women are 15%. For like this questionnaire, those who were graduated from. The national universities were more actively concerned than those graduated from the private universities. Christian was 35.4%, Catholic was 28.5% and buddhist was 14.9% and 17.4% had no religion. Now a day in generally, it is clearly confusing status between an ideal thinking and actuality in medical ethical aspects in Korea. They want more developed medical delivery system. The most of physicians are improving on four mind-sets, the mind of love, pity, joy and abandonment as much as they are cognizing that the pains of patients are themselves pains. But they do not want to be the ministry. On the problems of the easy to die, it seems that they have somewhat different opinions according to their religions, respectively;- christians are more responsible than others to keep to the terminal point of life of patients.

• Journal of Hospice and Palliative Care
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• v.17 no.2
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• pp.57-65
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• 2014

Purpose: Since most terminally ill cancer patients die of multiple organ failure, plasma endotoxin concentration levels may be used to predict the life expectancy. This study was performed to evaluate the clinical significance of endotoxin level in plasma as a prognostic factor for survival in patients with terminal cancer. Methods: This study was conducted with 56 terminally ill cancer patients, above 20 years old, from April 2009 through October 2009. Demographic characteristics, Karnofsky performance status, and survival time were evaluated. We analyzed blood levels of white blood cell hemoglobin, hematocrit, aspartate aminotransferase, alanine aminotransferase, c-reactive protein, total bilirubin and endotoxin in each patient. Results: We considered following variable for univariate analysis: plasma endotoxin level, sex, age, WBC, hemoglobin, hematocrit, AST, ALT, total bilirubin, CRP and severity of pain. Univariate analysis did not show a significant association between plasma endotoxin level and survival time. However, in a multivariate analysis with factors that were found to be significantly associated with survival sex, WBC count and total bilirubin level in univariate analysis, high levels of plasma endotoxin and short survival time were significantly related. Conclusion: Plasma endotoxin level could be used as a prognostic factor to predict the life expectancy of terminally ill cancer patients.