• The Korean Journal of Ecology
• /
• v.19 no.1
• /
• pp.31-37
• /
• 1996

The chigger mites known as the vectors of Tsutsugamushi disease seriously increased due to the expansion of their habitats by the change of farmland into idle land, arboreta and golf courses with the progress of industrialization. These mites were surveyed for their nymphs in soil of four areas located in the northern part of Kyonggido known as the outbreak areas of Tsutsugamushi disease. Total number of the chigger mites collected in the soil of four surveyed areas was 2576, and two genera and ten species including Leptotrombidium palpale were indentified. Among them L. pallidum was the dominant species with the highest occurrence rate of 62 percent. Nine species occurred on the bank of Changrungchon that has been idled for more than ten years, but six or seven species occurred in Wonhundong and Ilsandong that hans been idled for less than five years. The number of individuals collected was also higher in Changrungchon than the other sites. Seasonal occurrence of these mites showed a peak with 166 mites in November on the west slope and another with 192 mites in February on the east slope of the bank of Changrungchon, but none in June. Component ratio of individual numbers for L. palpale, L. pallidum, L. orientalis and L.scutelaris were 19, 62, 9 and 3 percent, respectively. Individual number of L. pallidum and L. scutelaris appeared to some extent of 397 and 23 mites, respetively.

• 한국생물공학회:학술대회논문집
• /
• 2000.04a
• /
• pp.512-515
• /
• 2000

In this study, ${\delta}-aminolevulinic$ acid, porphobilinogen, glycine and levulinic acid were succesfully separated by capillary electrophoresis(CE). We established the separative conditions of the mixture containing four components by CE. The borate buffered solution was used for CE electrolyte, and its pH was adjusted to $9.25{\sim}9.42$. Under constant current or constant voltage, higher concentraion of borate produced better resolution of four components, but adversely affected migration rates , resulting in longer analysis time. While migration time was faster with increase in applied voltage, but adversely affected resolution. Each component was separated well in borate buffer of 30mM at the applied voltage of 20kV.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.8 no.1
• /
• pp.26-32
• /
• 1988

This study was conducted to determine the effects of cutting frequency and cutting height on agronomic characteristics and yield performance of sorghum-sudangrass hybrid, cv. Pioneer 855 F on the experimental field of Livestock Experiment Station, Suweon. The results are summarized as follows: 1. The relative contribution of leaf component to total yield was higher when the plants were cut frequently rather than when defoliated only a few times, and tend to be higher with high cutting. 2. Leaf Area Index (LAI) was the highest at the primary growth of two cutting times scheme and the first regrowth for three or four cutting times a year, but LAI, in general, was not related to cutting height. 3. Crop Growth Rate was the heighest at the first regrowth-plants grown in summer, and it was also related to the amount of stubble left at the previous cut. 4. Dead stubbles were not occurred when plants were cut before heading, but those were accompanied by the frequent and low cutting. 5. Total fresh fodder and dry matter yield were the highest at two times cut a year, and decreased with frequent cutting. The optimum cutting height at two times cut was ca. lOCm height stubble from the ground level, but yield increased with higher level cutting at the three or four times cut a year.

• Asian-Australasian Journal of Animal Sciences
• /
• v.28 no.8
• /
• pp.1090-1094
• /
• 2015

The aim of the study was to select traits that may constitute a prospective criterion for breeding value prediction of young horses. The results of 1,232 starts of 894 four-, five-, six-, and seven-year-old horses, obtained during jumping championships for young horses which had not been evaluated in, alternative to championships, training centres were analyed. Nine traits were chosen of those recorded: ranking in the championship, elimination (y/n), conformation, rating of style on day one, two, and three, and penalty points on day one, two, and three of a championship. (Co)variance components were estimated via the Gibbs sampling procedure and adequate (co)variance component ratios were calculated. Statistical classifications were trait dependent but all fitted random additive genetic and permanent environment effects. It was found that such characteristics as penalty points and jumping style are potential indicators of jumping ability, and the genetic variability of the traits was within the range of 14% to 27%. Given the low genetic correlations between the conformation and other results achieved on the parkour, the relevance of assessment of conformation in four-years-old horses has been questioned.

• Journal of Applied Reliability
• /
• v.12 no.3
• /
• pp.201-213
• /
• 2012

A gear type lubrication pump is an essential component of the powertrain and has a major role for supplying oil to the gears and bearings in automatic transmission with a hydraulic clutch. Therefore, the durability test code design of lubrication pump is very important to ensure the reliability of the entire transmission and the vehicle. In this study, the design process for the life testing of lubrication pump has been generalized by four steps. The four design steps of the life testing of lubrication pump consist of the configuration of load spectrum, rain flow counting and analysis of load level, the equivalent damage assessment and test code generation. In fact, the load spectrum should be obtained from the field operating condition but that kind of data is the top secret of manufacturers. This is not open to the public in general. So we could use the artificially simulated load spectrum instead of field obtained one and focused on the development of the general process for designing the life test of a gear type lubrication pump. Reliability goals for lubrication pump, pressure, torque, temperature and load spectrum, if present, as appropriate for the given test conditions, accelerated life testing for the lubrication pump can be designed by the developed design steps.

• Journal of Korean Academy of Nursing
• /
• v.42 no.7
• /
• pp.1079-1086
• /
• 2012

Purpose: The purpose of this study was to develop and evaluate psychometric properties of the instrument, Resuscitation Self-Efficacy Scale for nurses. Methods: This was a methodological study for instrument development and psychometric testing. The initial item pool derived from literature review and experts resulted in 30 items linked to resuscitation self-efficacy. A convenience sample of 509 Korean nurses from eleven academic teaching hospitals participated in a survey to examine psychometric properties of the scale. To examine construct validity, exploratory factor analysis and known-group comparison were used. Cronbach's coefficient alpha was used to determine the scale's internal consistency reliability. Results: The final scale included 17 items with four-component structure termed 'Recognition', 'Debriefing and recording', 'Responding and rescuing', and 'Reporting'. These four factors accounted for 57.5% of the variance. Each subscale and the total scale demonstrated satisfactory internal consistency: .82; .88; .87; .83; and .91 respectively. Experienced nurses reported significantly higher self-efficacy mean scores in both total and subscales compared to new graduate nurses. Conclusion: The Resuscitation Self-Efficacy Scale for nurses yields reliable and valid results in appraising the level of resuscitation self-efficacy for Korean nurses. Further study is needed to test and refine the scale.

• Structural Engineering and Mechanics
• /
• v.23 no.6
• /
• pp.651-674
• /
• 2006

The fatigue cracks initiate and propagate in the Armored Vehicle Launch Bridge (AVLB) components, especially like the splice doubler angle, splice plate, and bottom chord, due to the cyclic loading by repeated AVLB-launchings and tank-crossings. In this study, laboratory fatigue tests were conducted on six aluminum 2014-T6, four aluminum 7050-T76511, and four ASTM A36 steel compact-tension specimens to evaluate the crack growth behavior of the materials used for the components. The experimental results provide the relationship (Paris Law) between crack growth rate, da/dn, and stress intensity range, ${\Delta}K$, whose material dependent constants C and m can later be used in the life estimation of the components. Finite Element Method (FEM) was used to obtain the stress intensity factor, K, of the components with cracks. Because of the complexity of loading conditions and component geometry, several assumptions and simplifications are made in the FEM modeling. The FEM results, along with the results obtained from laboratory fatigue tests, are then utilized to estimate critical crack length and remaining life of the components.

• Journal of Korean Academy of Fundamentals of Nursing
• /
• v.17 no.4
• /
• pp.487-497
• /
• 2010

Purpose: This study examined the validity and reliability to develop a lifestyle evaluation tool for metabolic syndrome patients. Methods: A methodological research design was used. The construct factors and preliminary items were identified by reviewing previous researches and tools related to lifestyle and reviewed by ten experts. It was tested with 195 patients with metabolic syndrome in a university hospital. The data were analyzed with SPSS/WIN 14.0. Results: To test the validity, principal component analyses were used and resulted in the extraction of six components. The convergent validity resulted r= .72 (p<.001) with Health Promotion Lifestyle Profile. The discriminant validity with Center for Epidemiologic Studies Depression Scale resulted r= -.15 (p=.004). The Internal consistency of the tool had an Cronbach's a of .92. The self-report format Lifestyle Evaluation Tool for the patients with metabolic syndrome was developed with 36 items and four-rating scales:'physical activity and weight control' eight items, 'dietary habits' sixteen items, 'drinking and smoking' three items, 'sleep and rest' two items, 'stress' three items, 'drug and health management' four items. Conclusion: This Tool will evaluate health behaviors in patients with metabolic syndrome. Also, it will contribute to the development of nursing intervention to improve the metabolic syndrome patients' lifestyle.

• Journal of Ecology and Environment
• /
• v.36 no.3
• /
• pp.205-210
• /
• 2013

Cicuta virosa L. (Apiaceae) is a perennial emergent plant designated as an endangered species in South Korea. According to the former records, only four natural habitats remain in South Korea. A former study suggested that three of four populations (Pyeongchang: PC, Hoengseong: HS, Gunsan: GS) would be classified as different ecotypes based on their different morphological characteristics and life cycle under different environmental conditions. To evaluate this suggestion, we estimated genetic diversity in each population and distance among three populations by random amplification of polymorphic DNA. Seven random primers generated a total of 61 different banding positions, 36 (59%) of them were polymorphic. Nei's gene diversity and the Shannon diversity index increased in the order of PC < HS < GS, which is the same order of population size. In the two-dimensional (2D) plot of first two principal components in principal component analysis with the presence of 61 loci, individuals could be grouped as three populations easily (proportion of variance = 0.6125). Nei's genetic distance for the three populations showed the same tendency with the geographical distance within three populations. And it is also similar to the result of discriminant analysis with the morphological or life-cycle factors from the previous study. From the results, we concluded that three different populations of C. virosa should be classified as ecotypes based on not only morphology and phenology but genetic differences in terms of diversity and distance as well.

• Journal of Family Resource Management and Policy Review
• /
• v.15 no.1
• /
• pp.71-91
• /
• 2011

This qualitative case study examines how mid-life housewives perceive age, react to aging, and experience the changing of their appearance that comes with age. The participants of this study were eight housewives four full-time housewives and four working housewives in middle adulthood. This study was conducted through in-depth interviews that were based on an unstructured questionnaire, and the data was collected from January 2010 to October 2010. Findings are as follows: during mid-life, housewives continue to exert efforts toward self-development, and toward self-actualization that can unleash the potential of their "multi-self". The housewives of the Entering Middle Adulthood self-actualization period believe that the material self as manifested in appearance is the most important component of the multi-self. Indeed, both groups of housewives thought a great deal about the criterion of appearance for their age and were concerned about others' viewpoints, social stereotypes, the appearance "norm," and other characteristics related to appearance. The full-time housewives made efforts to improve their social selves, and the working housewives tried to enhance their spiritual selves. The viewpoints of husbands are often internalized into housewives' internal points of view; therefore the relationships of housewives with their husbands were crucial both to the confidence the women felt in their appearance, and to their satisfaction in life.