• Title/Summary/Keyword: consistancy

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Erosion Control Effect by Soil ansi Vegetation Transition in Mountainous Area after Soil Erosion Measures were Initiated (토양 및 식생변화에 따른 토지 사방 공사의 효과에 관한 연구)

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    • Journal of the Korean Institute of Landscape Architecture
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    • v.14 no.2
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    • pp.7-16
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    • 1986
  • This study was carried out to investigate the effects of such erosion control measures as sowing, planting and small earth structures on the soil and vegetation. In order to study the changes in soil and vegetation, 36 plots were surveyed from 1981 to 1982 in the large erosion control area which is restored last 20 years. The factors which were measured included vegetation coverage, tree growth, number of species, soil depth, soil consistancy, and Chemical properties of soil. The results were as follows; 1) Maximum coverage of the overstory and understory was attained 7 years after the initiation of erosion control. So the overstory need to be tended and pruned. 2) Diversity of species increased until age 6 after which it began to decrease. 3) In order of tree growth, black locust was the fastest, followed by siberian alder and pitch pine. The initial growth of black locust, though the best among the 3 tree stop., decreased rapidly year by year. At the same time, siberian alder and pitch pine grew well until 12 and 6 years after the initiation of erosion control respectively. 4) Fifty percent of the initially planted trees died within 8 yeard. The mortality of siberian alder occurred until the 20th year while the mortality of pitch pine stopped after 10 years. Thereafter 500 trees per hectare were maintained. 5) The soil depth in A and B horision increased by 2cm annually during 20 years. The soil consistency also decreased rapidly until 7th year. The physical soil properties of the rehabilitated areas were improved after the 14th year. 6) The soil pH tend to decrease from 5.3 during the first year to 5.1 during the twentieth year. 7) The organic matter and nitrogen content in the soil were increased by fertilization but after 20 years these nutrients are still deficient for normal tree growth. 8) The phosphorous content in the soil was high in the first year but the longer the period after the initiation of erosion control the lese the content of phosphorous. 9) The biomass of black locust was the highest and increased continuously. The biomass of siberian alder on the contrary decreased from the 15th year because the number of trees in this place was very low. The total biomass in the twentieth year after erosion control initiation was 105.7 ton per hectare.

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An Elementary School Children Screen Test for Attention Deficit Hyperactivity Disorder in Taegu City (대구지역 국민학교 어린이의 주의력 결핍 과잉 운동 장애 경향에 대한 선별 검사)

  • Park, Hyung-Bae;Kim, Jin-Sung;Jang, Sang-Ruyl;Park, Sung-Chan;Suh, Hye-Sao;Lee, Kwang-Hun;Kim, Young-Uck;Kim, Chang-Su
    • Journal of Yeungnam Medical Science
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    • v.12 no.1
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    • pp.56-74
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    • 1995
  • The authors applied ADDES-HV parent evaluation scale for the purpose of screening test to 538 2nd grade elementary school students from March 1994 to May. The results were as follows: There was no differences in scores of ADHD between schools. In comparing the male and female between three school students, male students showed signifieant high scores (p<0.05) than female students in the score of ADDES-HV subscale and total. There was no significant differences in ADDES-HV scale between male students and female students in both ADHD patients and normal controls. In reliability test for test and retest, the reliability coefficient was higher satisfatorily and that of inattention was 0.80, inpulsivity was 0.69, hyperactivity was 0.63 and the total score was 0.82. In reliability test by internal consistancy, the Cronbach ${\alpha}$ coefficient of patient group was 0.85(p<0.05) and that of normal control was 0.84(p<0.05). The Concurrent validity between ADDES-HV scale and DSM-III-R scale was 0.57(p<0.05) in ADHD patient group and 0.84(p<0.05) in normal control group. In discriminant validity test between ADHD patient group and normal control, the ADHD patient group showed higher score(p<0.05). The total disciminant capacity of the patient group in ADDES-HV scale was 94.44%. When we regard the cut off point as standard deviation 1.5, the male student was 80 score and the female student was 69 score. In this point of view, ADDES-HV scale was proved to be the useful screening test tool for ADHD research and showed higher reliability and validity in applying to Korean subjects.

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