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The Variation of Natural Population of Pinus densiflora S. et Z. in Korea(I) -Characteristics of Needle and Wood of Chuwang-san, An-Myeon-do and Odae-san Populations- (소나무 천연집단(天然集團)의 변이(變異)에 관(關)한 연구(硏究)(I))

  • Yim, Kyong-Bin;Kim, Zin-Suh
    • Journal of Korean Society of Forest Science
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    • v.28 no.1
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    • pp.1-20
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    • 1975
  • F$\ddot{u}$r die Erforschllng der Variationen bei der Naturpopulationen der Pinus densifiora wurden drei Populationen aus Chuwangsan (Kyong-buk), Anmyondo (Chung-nam) und Odaesan (Kangwon) Ausgewiiblt. Bei je 20 Individuen jeder Population wurden die Variationen von der Eigenschaft der $\ddot{a}$usseren Gestalt, von der anatomischen und morphologischen Eigenschaft der Kiefernadel und von der Holzqualit$\ddot{a}$t an Bohrsp$\ddot{a}$nen untersucht. Das Ergebnis der Untersuchung konnte in den folgenden sechs Punkten formuliert werden. 1. Von den Eigenschaften der $\ddot{a}$usseren Gestalt ist die Geradheit des Baumstamms, der Durchmesser der Zweige und der Winkel der Verzweigung in der Odaesan Population wlinschenswerter als in anderen Populationen. 2. Es wird festgestellt, dass sich die drei Nadelmerkmale, Anzahl der Z$\ddot{a}$hne je 0.5 cm, Anzahl der Stomata-Reihen und Anzahl der Harzkan$\ddot{a}$le, sowohl zwischen den Populationen als auch zwischen den Individuen signignifikant unterscheiden. 3. Bei der Betrachtung des Harzkanal Index, der Schichtanzahl der Hypodermis und der Entfernung der Fibrovasalb$\ddot{u}$ndel wird aufgezeigt, dass sich alle drei gepr$\ddot{u}$ften Populationen geringf$\ddot{u}$gig von der normalen Kiefer unterscheiden. 4. Zwischen den Populationen ergibt sich ein Unterschied im Prozentanteil des Spatho lzes und im spezifischen Geswicht, jedoch zeigt die Breite der Jahresrings und die Tracheidenl$\ddot{a}$nge keinen Unterschied. Das spezifische Gewicht und die Tracheidenl$\ddot{a}$nge der Individuen jeder Population ist signifikant verschieden. 5. Bei dem Alter 11-20 ist der Prozentanteil des sp$\ddot{a}$tholzes am gr$\ddot{o}$ssten und wird aber danach immer geringer bis zum Alter 30; sp$\ddot{a}$ter zeigt sich dann keine sichtbare Ver$\ddot{a}$nderung mehr. Das spezifische Gewicht sich vergr$\ddot{o}$ssert bei der Zunahme des Jahresrings, nimmt aber dann in Anmyondo und Odaesan Populationen beim Alter 21-30 wieder ab. Die Tracheidenl$\ddot{a}$nge der drei Populationen besitzen die Neigung, sich nach der zunahme der Jahresringe zu vermehren. 6. Mit diesen hier behandelten Charakteren werden ganz allgemeinen die Unterschiede der drei Kiefer populationen festgestellt. Diese Ergebnisse sind sehr bemerkenswert betrachtet vom genetischen Gesichtspunkt der waldbaumpopulation.

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Factors associated with the bone mineral density in Korean adults: Data from the 2010-2011 Korean National Health and Nutrition Examination Survey (KNHANES) V (우리나라 성인남녀의 골밀도 관련요인: 국민건강영양조사 제 5기 1, 2차 년도(2010년, 2011년))

  • Kim, Kyung Sook
    • Journal of agricultural medicine and community health
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    • v.39 no.4
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    • pp.240-255
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    • 2014
  • Objective: The purpose of this study was to identify the correlates of bone mineral density of Korean adults. Methods: This study was based on the data from the 2010-2011 Korean National Health and Nutrition Examination Survey (KNHANES, 2010~2011) V. Among 8,473 subjects of the survey, who were adults 19 years old or over with bone mineral density data, the current study excluded those whose data include a missing study variable or the response of 'I don't know', and finally analyzed the data of 5,986 subjects (2,692 males and 3,294 females). This study employed the following statistical methods of analysis: t-test, analysis of variance (ANOVA), and hierarchical multivariate linear regression analysis. Results: In multivariate analysis, in the case of men, the significant associated factors in bone mineral density were age, education level, body mass index (BMI), waist circumference, total muscle mass, exercise, and weight control; in the case of women, the significant associated factors in bone mineral density were age, education level, economic activity, BMI, total muscle mass, exercise, weight control. fat intake, uptake female hormone, menopause, and age of menarche. Conclusion: For both sexes, the strongest modifiable factor in influencing bone mineral density was total muscle mass. Therefore, to prevent osteoporosis and promote health, active health education and interventions such as regular exercise for total muscle mass increase should be implemented from an early growth period.

A Study on Business Diversification and Business Performance of Korean Mass Media Enterprises (국내 매스미디어 기업의 사업다각화와 경영성과에 관한 연구)

  • Chang, Yun-Hi
    • Korean journal of communication and information
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    • v.43
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    • pp.173-208
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    • 2008
  • This study analyses the business performance according to the business diversification of Korean mass media enterprises from year 2003 to 2006. The conclusions drawn which could be divided into five main parts are the followings: First, newspaper companies pursue unrelated diversification in various industrial areas, in order to gain maximum profit while broadcasting companies exert themselves to provide better service by diversifying the major contents. Second, overall the interviewed companies display a constant decline in profit gained from their major business area thus establishing strategies to broaden their focus on diversification of any sort. Third, the researcher completed group analysis in regard of diversification measure resulting in division of three groups. The group which had the most immense diversification range gained the highest ROE, the lowest ROE volatility, and lesser probability of risk taking. The analysis adresses the companies broadening their business areas by researching and focusing on diversification are relatively stable in terms of the profit they gain. Fourth, the middle level group in terms of sales scale, debts, enterprise history, major share rate and high ROE group carry out diversification progressively. The sales scale affects positively to diversification, while the major share rate affects negatively to diversification. Fifth, in accordance to the research, diversification overall contributes to obtainance of successful outcome. Since there was not an immense amount of studies to be referred in the media area, the researcher interviewed and did panel discussion with numerous strategists and managers who are in charge of diversification of media companies. However, collection of only 4 years of data limits the research to be considered to be a generalized study, and does not reflect time gap between business diversification and business performance. Development is required in future studies to be established regarding the media companies' specificity different to other industries, classified the media companies into media types, and consider the time gap in the diversification activities and business performance.

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The Health Status of Rural Farming Women (농촌여성(農村女性)의 건강실태(健康實態)에 관한 연구(硏究))

  • Park, Jung-Eun
    • Journal of agricultural medicine and community health
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    • v.15 no.2
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    • pp.97-106
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    • 1990
  • 1. Background Women's health and their involvement in health care are essential to health for everyone. If they are ignorant, malnourished or over-worked, the health &-their families as well as their own health will suffer. Women's health depends on broad considerations beyond medicine. Among other things, it depends upon their work in farming. their subordination to their families, their accepted roles, and poor hygiene with poorly equipped housing and environmental sanitation. 2. Objectives and Contents a. The health status of rural women : physical and mental complaints, experience of pesticides intoxication, Farmer's syndrome, experiences of reproductive health problems. b. participation in and attitudes towards housework and farming c. accessibility of medical care d. status of maternal health : fertility, family planning practice. induced abortion, and maternal care 3. Research method A nationwide field survey, based on stratified random sampling, was conducted during July, 1986. Revised Cornell Medical index(68 out of 195 items). Kawagai's Farmers Syndrome Scale, and self-developed structured questionnaires were used to rural farming wives(n=2.028). aged between 26-55. 4. Characteristics of the respondents mean age : 40.2 marital status : 90.8% married mean no. of household : 4.9 average years of education : 4.7 yrs. average income of household : \235,000 average years of residence in rural area : 36.4 yrs average Working hours(household and farming) : 11 hrs. 23 min 5. Health Status of rural women a. The average number of physical and mental symptoms were 12.4, 4.7, and the rate of complaints were 22.1%, 38.8% each. revealing complaints of mental symptomes higher than physical ones. b. 65.4% of rural women complained of more than 4 symptoms out of 9, indicating farmer's syndrome. 11.9 % experienced pesticide overdue syndrome c. 57.6% of respondents experienced women-specific health problems. d. Age and education of respondents were the variables which affect on the level of their health 6. Utilization of medical services a. The number of symptoms and complaints of respondents were dependent on the distance to where the health-care service is given b. Drug store was the most commonly utilized due to low price and the distance to reach. while nurse practitioners were well utilized when there were nurse practitioner's office in their villages. c. Rural women were internalized their subordination to husbands and children, revealing they are positive(93%) in health-care demand for-them but negative(30%) for themselves d. 33.0% of respondents were habitual drug users, 4.5% were smokers and 32.3% were alcohol drinkers. and 86.3% experienced induced-abortion. But most of them(77.6%) knew that those had negative effects on health. 7. Maternal Health Care a. Practice rate of contraception was 48.1% : female users were 90.9% in permanent and 89.6% in temporary contraception b. Induced abortions were taken mostly at hospital(86.3%), while health centers(4.7%), midwiferies(4.3%). and others(4.5%) including drug stores were listed a few. The repeated numbers of induced abortion seemed affected on the increasing numbers of symptoms and complaints. c. The first pre-natal check-up during first trimester was 41.8%, safe delivery rate was 15.6%, post-natal check-up during two months after delivery. Rural women had no enough rest after delivery revealing average days of rest from home work and farming 8.3 and 17.2. d. 86.6% practised breast feeding, showing younger and more educated mothers depending on artificial milk 8. Recommendations a. To lessen the multiple role over burden housing and sanitary conditions should be improved, and are needed farming machiner es for women and training on the use of them b. Health education should begin at primary school including health behavior and living environment. c. Women should be encouraged to become policy-makers as well as administrators in the field of women specific health affairs. d. Women's health indicators should be developed and women's health surveillance system too.

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Regression Modeling of Water-balance in Watershed (유역(流域) 물 수지(收支)의 회귀모형화(回歸模型化))

  • Kim, Tai Cheol
    • Korean Journal of Agricultural Science
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    • v.10 no.2
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    • pp.324-333
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    • 1983
  • Modeling of longterm runoff is theoritically based on waterbalance analysis. Simplified equation of water balance with rainfall, evapotranspiration and soil moisture storage could be formulated into regression model with variables of rainfall, pan evaporation and previous-month streamflow. The hydrologic response of water shed could be represented lumpedly, qualitatively and deductively by regression coefficients of water-balance regression model. Characteristics of regression modeling of water-balance were summarized as follows; 1. Regression coefficient $b_1$ represents the rate of direct runoff component of precipitation. The bigger the drainage area, the less $b_1$ value. This means that there are more losses of interception, surface detension and transmission in the downstream watershed. 2. Regression coefficient $b_2$ represents the rate of baseflow due to changes of soil moisture storage. The bigger the drainage area and the milder the watershed slope, the bigger b, value. This means that there are more storage capacity of watershed in mild downstream watershed. 3. Regression coefficient $b_3$ represents the rate of watershed evaporation. This depends on the s oil type, soil coverage and soil moisture status. The bigger the drainage area, the bigger $b_3$ value. This means that there are more watershed evaporation loss since more storage of surface and subsurface water would be in down stream watershed. 4. It was possible to explain the seasonal variation of streamflow reasonably through regress ion coefficients. 5. Percentages of beta coefficients what is a relative measure of the importance of rainfall, evaporation and soil moisture storage to month streamflow are approximately 89%, 9% and 11% respectively.

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Effect of Slow-release Fertilizer Levels of Rice in Different Cultural Methods (벼 재배양식에 따른 유효성 비료의 시용량이 생육과 수량에 미치는 영향)

  • 정진일;최원영;최민규;이선용
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.40 no.6
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    • pp.747-756
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    • 1995
  • To find out the optimum application method of slow-releasing fertilizer(SRF) and conventional fertilizer(CF) with different fertilization rate under two culture methods[l0-day old seedling machine transplanting(MT) and direct-sowing on dry paddy(DS)] in the south-western region(clay loam soil) of Korea, used were Chosun slow-releasing fertilizer(silicate latex coated fertilizer: N-P$_2$O$_{5}$-K$_2$O =18-12-13) and conventional fertilizer. Plant height and number of tillers with different two culture methods were higher at MT than DS in early growth. The ratio of dry weight in heading stage was higher at CF than SRF in MT than DS and especially, SRF 80% + CF 20% than SRF 100% or CF 100%. Leaf area index (LAI) in heading stage was higher at CF in MT but higher at SRF in DS than their counterparts. Chlorophyll content was higher at SRF than in CF expect for heading stage(HS), especially in DS. It was highest at HS in CF without its difference during maximum tillering stage(MTS) and panicle formation stage(PFS), while highest at PFS in SRF with tendency of gradual increase and decrease before and after PFS, respectively. Heading was delayed 2~3 days at SRF in two cultrue methods and 4~5 days at SRF in DS in comparison with CF in MT with delay of 2 days at DS compared with MT. Culm length was longer at CF in MT and at SRF in DS than their counterparts. Panicle number per m was more at SRF and in DS. Filled grain ratio was higher at CF and in MT. Yield was obtained 101 and 100% at 100% and 80% level of SRF in DS respectively, and 96% at 80% level of CF in MT, compared with conventional application method (516kg /l0a), and increased 2~4% at DS and 0~3% at MT in SRF. Yield was high in order of 100%(SRF) =80%(SRF) + 20%(CF) > 100%(SRF) + 20%(CF) > 80%(SRF) at MT and 80%(SRF) + 20%(CF) =100%(SRF) > 80%(SRF) =100%(SRF) + 20%(CF) at DS.

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A Study on the Cause of Death of School Teachers in Korea (한국 교원의 사인에 관한 연구)

  • Lee, Sung-Kwan
    • Journal of Preventive Medicine and Public Health
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    • v.20 no.1 s.21
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    • pp.10-39
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    • 1987
  • Mortality rate and causes of death are regarded as an index of strength as well as level of development of a country. However, there is no accurate data for the causes of death in Korea due to lack of systematic vital data collection system. The objective of this study was to define the causes of death of the school teachers, its changing pattern, cause-specific mortality rate, and geographic variation. The study population included all of the teachers in primary school, middle and high schools, and college who joined in Korean Teachers' Union between 1968 and 1985 that provided a total of 1,972, 069 person-years to observe (1,384,911 man-years, 587,158 woman-years). There were 3,678 deaths in this period (3,377 males, 301 females). The most common cause of death was neoplasm which was followed by the diseases of circulatory system. The proportion of death of neoplasm was 1.5 times higher than that of the general population. Causes of death were classified into 5 major groups (neoplasm, diseases of circulatory system, accidents and poisoning, diseases of liver, and all others). The mortality rates of diseases of circulatory system and all others for general population were 4 to S times higher than those for the teachers. However, mortality rates of neoplasm and diseases of liver were only about 2 times higher than those for teachers. Mortality rate of liver cancer for teachers was higher than gastric cancer mortality rate which is the reverse in general population. The crude death rate was 2.12 per 1,000 person-years for male and 1.00 for female which is one-third of the crude death rate of general population. Crude death rate of study population was higher in rural area than in urban area. However, mortality rate of neoplasm for male was higher in urban area than in rural area while mortality rates of all other causes were higher in rural area. For female, mortality rates of neoplasm and diseases of circulatory system were higher in urban area and the rates for all other causes were higher in rural area. Crude death rate was lowest in Gyeongin area and highest in Yeongnam area. The mortality of neoplasm for male accounted the highest proportion of all death in Gyeongin, Chungcheong and Yeoungnam areas while the mortality of neoplasm and mortality of circulatory system accounted the same proportion in Jeonra area. For female, the mortality of disease of circulatory system accounted the highest proportion in Gyeongin and Yeoungnam and Jeonra areas. Proportion of death due to accidents and poisoning was high in Chungcheong area and death due to all other causes was high in Yeoungnam area. The most common cause of death for male by city and province was neoplasm in Seoul, Busan, Daegu, Gyeonggi, Chungnam, Chungbuk, Gyeongnam and Gyeongbuk. Diseases of circulatory system was the leading cause of death in the rest of city and provinces. The leading cause of death for female was diseases of circulatory system in Seoul, Incheon, Chungbuk, Chungnam, and Gyeongbuk, neoplasm in Busan, and accident and poisons in all other cities and provinces. The mortality rates of male were above 2 per 1,000 person-years in Jeju, Gyeongbuk, Gyeongnam, Daegu, and Chungbuk, and it was below 1.5/l,000 in Seoul, Incheon and Gyeonggi. The mortality rate of female was above 1.2/1,000 person-years in Gyeongnam and Incheon while it was below 0.5/l,000 in Daegu, Geonggi Chungbuk and Jeju. The leading cause for male by school of employment was neoplasm in all levels of school with a remarkably higher rate in the professors of college. Leading cause of death for female was disease of circulatory system in primary schools, high schools and college but neoplasm in middle schools. There was no death due to liver diseases in middle and high school teachers and college professors and no death due to all other category in high school teachers and college professors, in females. High school teachers and the highest mortality rate and college professors showed the lowest mortality rate. Temporal trend of mortality was examined in three periods; period I ($1968{\sim}1974$), period II ($1975{\sim}1979$), and period III ($1980{\sim}1985$). The leading cause of death for male was diseases of circulatory system in period I and II but neoplasm in period III. Such trend of decreasing diseases of circulatory system and increasing neoplasm was observed in female. Overall mortality rate was decreased over the 3 periods. The mortality rates of diseases of circulatory system, liver disease and all others were decreased in male but the mortality rates of neoplasm and accident and posions was increased. Female showed a similar trend to male but the mortality rate of liver diseases was increased. Mortality rates of diseases of circulatory system, neoplasm and liver diseases increased with age of teachers up to 50 years of age but decreased in 60 years of age. Mean age at death due to each cause was higher in male than female by $4{\sim}10$ years. However, the mean age at death of the teachers was $2{\sim}5$ years lower than that of the general population in all causes of death and the sex difference in the mean a2e at death was smaller ($2{\sim}3$ years) in general population. In sex ratio of mortality, male was higher than female in almost all diseases except suicide and maintained a high ratio. The general population showed universally high ratio in male like teachers, and more or less did regular patterns in mortality with ratio smaller.

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The Effect of Rapidly Rotating Shift work on the Fatigue Level, Urinary 17-KS, $Na^+$ and $Cl^-$ Excretion (빠른 교대근무가 피로도, 요중 17-KS, $Na^+,\;Cl^-$ 배설에 미치는 영향)

  • Jung, Young-Ju
    • Journal of Korean Biological Nursing Science
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    • v.1 no.1
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    • pp.100-114
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    • 1999
  • This study was done to investigate the effects of rapidly-rotating shift work of two-day interval on fatigue level and the concentration of urinary 17-KS, $Na^+,\;Cl^-$. The subjects were 20 nursing college students(control group) and 15 nurses in a university hospital and the study was done from Apr. 21 to May 4th, 1999. In the test group, each 5 nurses were allocated to day shift(8 AM-4 PM), evening shift(4 PM-12 MN) and night shift(12 MN-8 AM) respectively. The fatigue level were measured 30 minutes after work start on the 2nd day of work shift. Urine specimens were collected at 8 AM, 4 PM and 12 MN on the 2nd day of work shift in the control group and 30 minutes before and after work on the 2nd day of work shift in the test group. The data were analyzed with SPSS(for Window, ver 7.5). Statistical analysis was performed by using t-test, paired t-test and ANOVA. The results were as follows. 1. The perceived fatigue level in shift work 1) The physical and mental fatigue level were significantly higher in night shift than that in day or evening shift(p<0.05). In the neuro-sensory fatigue level, night shift showed higher tendency than that in day or evening shift, but there were no significant differences between each shifts. 2) Comparison between the control group and the test group: Physical fatigue level was significantly higher in night shift than that in day or evening shift of the control group(P<.001). Mental fatigue level was significantly higher in day or night shift than that in evening shift of the control group(P<.05). In the neuro-sensory fatigue level, test group showed higher tendency than that in the control group, but there were no significant differences between two groups. 3) The total fatigue level was higher in night shift than that in day shift or evening shift(P<.05). In comparing with the control group, night shift and day shift showed higher total fatigue level than that in the control group(p<0.05). 2. The concentration of urinary 17-KS, $Na^+$ and $Cl^-$ In the control group, urinary 17-KS, $Na^+$ and $Cl^-$ showed higher level in afternoon that in morning and night. In the test group, cr in day and evening shift and $Na^+$ in evening shift showed higher level at the end of work. The 17-KS concentration at the begining and the end of work in three shift groups were lower than those in control group(p<0.05), however, $Cl^-$ concentration at the begining of work in day shift, and the end of work in day and evening shift were higher than those in control group(p<0.05). $Cl^-$ concentration at the begining and end of work in night shift were considerably higher than those in control group repectively(p<0.1, p<001). $Na^+$ concentration showed a higher tendency in three shift groups except at the begining of work in night shift, but there were no statistical difference. In comparing concentration of the 17-KS, $Na^+$ and $Cl^-$ among the shift groups, 17-KS concentration showed a lower tendency and $Na^+,\;Cl^-$ showed a higher tendency in night shift: The result of this study showes that biorhythm of shift work nurse was irregular. Fatigue level as the subjective index for evaluating the health problem concerning shift work was higher in night shift and proved to be in accordance with the concentration of urinary 17-KS, $Na^+$ and $Cl^-$ used as objective indices. Disturbation of biorhythm and work stress due to night shift seems to cause the health problem of nurses and decrease of work efficiency. It is considered that work regualtion is necessary for the rational management of the nursing administration.

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A Taxonomic Study of the Genera Acanthogobius and Synechogobius (Pisces : Gobiidae) from Korea (한국산(韓國産) 문절망둑 속(屬)과 풀망둑속(屬) 어류(魚類)의 분류학적(分類學的) 연구(硏究))

  • Lee, Yong-Joo
    • Korean Journal of Ichthyology
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    • v.4 no.2
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    • pp.1-25
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    • 1992
  • Taxonomic study of the five species (Acanthogobius elongata, A. flavimanus, A. lactipes, A. luridus and Synechogobius) from Korea was carried out based on morphometric, cephalic sensory canal and ecological characters. Taxonomic revision and classificational keys are provided. Synechogobius hasta is easily distinguished from four species of the genus Acanthogobius in eleven characters, i. e., the number of dorsal and anal fin rays, the transverse scales, the vertebral numbers, the formula of interneural spine of the first dorsal fin, the number of interhemal spine anterior to the first hemal spine, the number of epipleural and pleurals, the ratio of caudal peduncle length, the ratio of caudal peduncle depth and the regular variations in the ratio of body parts with the body length. In the genus Acanthobobius, A. elongata is distinguished from other 3 congeneric species in the ratio of body parts and the oculoscapular sensory canal. Moreover, A. flavimanus differs from other 3 congeneric species in the lateral scales, the transverse scales, the number of predorsal scales, the vertebral number, the number of epipleural and pleurals. Sensory papillae rows of S. hasta is not similar that of the genus Acanthogobius in having a singular sensroy papillae rows. A. elongata has no oculoscapular sensory canal D and A. flavimanus has transverse sensory papillae in cheek, and these are one of the unique characters distinguished form other congeneric species. In the spawning period inferred from gonadosomatic index, A. elongata varied from late March to late June ; A. flavimanus, January to April ; A. lactipes, May to September ; A. luridus, early May to early July and S. hasta, early March to early May.

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Forest Soil Characteristics and their Effects on the Trafficability of Logging Vehicles (산림토양(山林土壤) 특성(特性)이 집재차량(集材車輛)의 주행성(走行性)에 미치는 영향(影響))

  • Kim, Ki Weon
    • Journal of Korean Society of Forest Science
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    • v.88 no.2
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    • pp.255-265
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    • 1999
  • This study deals with forest soil characteristics and their effects on the trafficability of logging vehicles. The study area is the national experimental forest located in Kwangnung. This site has 20m length and is equally divided by 5 surveying ranges with 4m width, on which a tractor(FIATAGRI) attached with logging boogie can drive in 4 driving types, namely 1time-return unload, 1time-return with load of 780-790kg weight of 3 logs, 5 and 10times-return with same load. After one driving type on all surveying ranges, the soil hardness is surveyed 5 times with 3 several type tools, SHM-1 type, lang penetrometer(L-PNTM), and clegg impact soil tester(CIST). A disturbed degree of cover vegetation and sliding conditions of vehicle are also observed. As results, the soil type of the test site was SC by USCS and dry brown forest soil. The cover vegetation is gotten trambled under driving after 3-5 times-return, shrubs leaves are fully fallen and their bark are peeled, and after 10 times-return the cover vegetations were nearly disappeared. The test vehicle has neither slided nor was overthrown. The wheel tracks in the 1-3 ranges, of which unit weight(gd, gt) is high and soil moisture content(MC) is low, were only 1-2cm deep, but those in the 4-5 ranges, of which the gd, gt is low and the MC is high, were 5-7cm deep. In the soil hardness test, which was established in 5 test ranges by types of driving, the more driving times, the higher the hardness. The soil hardness surveyed by L-PNTM has changed slowly and that surveyed by SHM-1 type has risen sharply. In the ranges with higher specific gravity(Gs), higher unit weight, lower MC and higher liquid limit(LL) and plasticity index(PI) was the soil hardness high and the trafficability was good. In the ranges with opposite conditions, also in the ranges of the lower soil hardness, the trafficability must be not good, because the wheel track may be deep. The results from CIST attached with 4kg hammer was not better than expected. So it is recommended to use CIST with 2.5kg or 0.5kg hammer.

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