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Xylem Sap Flow Affected by Short-term Variation of Soil Moisture Regimes at Higher Growth Period in 'Fuji'/M.9 Apple Trees with Different Fruit Loads (착과량 수준 및 생육성기 토양수분 함량 변화에 따른 '후지'/M.9 품종의 수액이동 특성)

  • Park, Jeong-Gwan;Kim, Seung-Heui;Lee, In-Bok;Park, Jin-Myeon
    • Korean Journal of Environmental Agriculture
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    • v.25 no.2
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    • pp.164-169
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    • 2006
  • This study was conducted for 10 days from 17 July to 26 July in 2005 to measure the amount of xylem sap flow under short-term variation of soil moisture regimes at -20 kPa, -50 kPa and -80 kPa in eight-year-old 'Fuji'/M.9 apple trees with different fruit loads. Fruit load was adjusted as three different treatments with standard (100%), 1/2 times (50%) and 2 times (200%) on the basis of optimum fruiting number per tree as the standard fruit load of Fuji cultivar. Trees with standard fruit load during the experimental period showed higher xylem sap flow at -50 kPa of soil moisture regimes than those of trees with 1/2 times and 2 times fruit load. Trees with 1/2 times and 2 times fruit load had similar patterns of the diurnal changes of xylem sap flow, vapor pressure deficit (VPD), and maximum evapotranspiration (ETm). However, trees with 2 times fruit load at -50 kPa and -80 kPa of soil moisture regimes produced lower amount of xylem sap flow than ETm. Trees with standard fruit load produced $1.06{\sim}3.93$ L/tree more amount of xylem sap flow than ETm at all soil moisture regimes. But xylem sap flow of tees with 2 times fruit load had 21% lower at -50 kPa and $31{\sim}36%$ lower at -20 kPa and -80 kPa of soil moisture regimes, respectively than that of trees with standard fruit load. Shoot growth and leaf area were significantly the highest in trees with standard fruit load while those of trees with 2 times fruit load recorded significantly lowest. Leaf water potential of trees with standard fruit load was lower than that of trees with 1/2 times and 2 times fruit load. It indicated that tees with standard fruit load had higher water use for transpiration than other treatments and tees with 2 times fruit load received more stress for the transpiration process under low soil moisture regimes. Consequently, 'Fuji'/M.9 apple trees, the fruit load and soil moisture should be maintained optimum to increase xylem sap flow and transpiration during higher growth period.

A Comparative Study on Physics Inquiry Activities in Science Textbooks for Primary School in Korea and Singapore (우리나라와 싱가포르의 초등학교 과학 교과서에 제시된 물리 영역 탐구 활동의 특징 비교)

  • Jung, Hana;Jhun, Youngseok
    • Journal of Science Education
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    • v.36 no.1
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    • pp.139-152
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    • 2012
  • The purpose of this study is to provide some suggestions for future improvement of scientific inquiry activities in Korean elementary science textbook. The modified framework of Lee(2005) and Millar et al.(1998) was used to compare inquiry activities in the Korean and Singaporean science textbooks. The results of this study are as follows: Korean text books have more activities than Singapore's, but both countries have similar time allotment for science classes. In the area of 'inquiry process skill', Singapore is more balanced in 'Basic inquiry process skills' and 'Integrated inquiry process skills' than Korea. Singapore's integrated inquiry rate is also higher than Korea's. Next the results of comparing leaning objectives to scientific inquiry activities shows that Korean text books tend to focus on 'contents objectives', while Singapore's text books focus on balancing 'contents objectives' and 'process objectives'. Korean science textbooks encourage students to communicate the results of experiments but in most case these communication activities are actually not performed. Lastly Korea and Singapore have low degree of openness in inquiry activities. Remarkably 'Suggest questions' are totally conducted by teachers. This study implies that Korean science textbooks should have lower amounts of inquiry activities to accomodate enough time for communication about results. Next we need to make balance not only 'Basic inquiry process skills' and 'Integrated inquiry process skills' but also 'Content objectives' and 'Process objectives'. Lastly we need to make student to be the leader in science classes through encouraging them to plan procedures for experiments and to discover results by themselves.

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Physico-chemical Characteristics and In situ Fish Enclosure Bioassays on Wastewater Outflow in Abandoned Mine Watershed (폐광산 지역의 유출수에 대한 이.화학적 수질특성 및 Enclosure 어류 노출시험 평가)

  • An, Kwang-Guk;Bae, Dae-Yeul;Han, Jeong-Ho
    • Korean Journal of Ecology and Environment
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    • v.45 no.2
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    • pp.218-231
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    • 2012
  • The objectives of this study were to evaluate the physico-chemical water quality, trophic and tolerance guilds in the control ($C_o$) and impacted streams of the abandoned mine, along with the ecological health, using a multimetric health model and physical habitat conditions of Qualitative Habitat Evaluation Index (QHEI), during the period of three years, 2005~2007. Also, eco-toxicity ($EE_t$) enclosure tests were conducted to examine the toxic effects on the outflows from the mine wastewater, using the sentinel species of Rhynchocypris oxycephalus, and we compared the biological responses of the control ($C_o$) and treatment (T) to the effluents through a Necropybased Health Assessment Index ($N_b$-HAI). Tissue impact analysis of the spleen, kidney, gill, liver, eyes, and fins were conducted in the controlled enclosure experiments (10 individuals). According to the comparisons of the control ($C_o$) vs. the treatment (T) in physicochemical water quality, outflows from the abandoned mine resulted in low pH of 3.2, strong acid wastewater, high ionic concentrations, based on an electrical conductivity, and high total dissolved solid (TDS). Physical habitat assessments, based on Qualitative Habitat Evaluation Index (QHEI) did not show any statistical differences (p>0.05) in the sampling sites, whereas, the $M_m$-EH model values in a multimetric ecological health ($M_m$-EH) model of the Index of Biological Integrity (IBI), using fish assemblages, were 16~20 (fair condition) in the control and all zero (0, poor condition) in the impacted sites of mine wastewater. In addition, in enclosure eco-toxicity ($EE_t$) tests, the model values of $N_b$-HAI ranged between 0 and 3 in the controls during the three years, indicating an excellent~good condition (Ex~G), and were >100 (range: 100~137) in the impacted sites, which indicates a poor condition (P). Under the circumstances, organ tissues, such as the liver, kidney, and gills were largely impaired, so that efficient water quality managements are required in the outflow area of the abandoned mine watershed.

A Demonstrative Study on the Intake Habits of Dairy Goats (Saanen) Fed with Roughages (유산양의 조사료 채식습성에 관한 실증적 연구)

  • Gang, Byung-Ho;Lee, In-Duk;Lee, Hyung-Suk
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.29 no.1
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    • pp.63-72
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    • 2009
  • The experiment was conducted from 2007 to 2008. The experimental roughages include five sources and 25 species in all; grasses and legumes: 5 species (mixed grasses, orchardgrass, tall fescue, alfalfa, white clover), native grasses and weeds: 5 species (mixed native grasses, Miscanthus sinensis Anderss, Arundinella hirta (Thunb.) Tanaka, barnyard grass, short awn, forage crops and straw: 5 species (barley 4- hairy vetch, wheat 4- hairy vetch, rye silage, barley silage, baled rice straw), browse and fallen leaves: 5 species (mixed browse, oriental white oak browse, Quercus serrta Thunb., browse oriental cherry fallen leaves, Japanese chestnut fallen leaves), and imported hay and straw: 5 species (timothy hay, tail fescue straw, annual ryegrass straw, klinegrass hay, alfalfa hay). Ten dairy goats (Saanen) were selected which had nearly the same body weight (25kg). The experiment was carried out on the dairy goats farm at Geumsan-Cun in Chungnam province. The chemical composition and dry matter digestibility of each roughage source and species were significantly different at the sampling area, plant species, growth stages and cutting period. Among all the 25 species of roughages, the favorite intake species order by dairy goats was observed like this: mixed grasses, white clover, alfalfa and the lower intake species order was baled rice straw and rye silages. The dairy goats ate more roughages which had low fibrous contents, but high dry matter digestibility. On the other hand, compared to each roughage source, the goat's favorite roughage were grasses and legumes (34.6%) among the trial species. Based on the result, it is reconfirmed that the food habit of dairy goats seems to be closer to that of graters.

Influence of the Hoping Number of Children, the Policy of Childbirth, and the Causes of Reduced Childbirth to the Perception of Childbirth in Health-Line College Students (일 지역 보건계열 대학생을 대상으로 한 희망자녀수, 출산정책, 출산저하 원인이 출산인식에 미치는 영향)

  • Jung, Sang-Jin
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.8
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    • pp.5031-5041
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    • 2014
  • Purpose: The influence of the hoping number of children, the policy of childbirth, and the causes of reduced childbirth to the perception of childbirth, which will be the subject of future childbirth, was surveyed by health-line college students. Results: In terms of the attitude to the perception of childbirth, the quality of personal life, childcare, insufficient support of childbirth, and breeding of descendants had the largest influence on childbirth, and in terms of the attitude to the hoping number of children, economic reasons, childcare expenses, and education expenses had the largest influences. Second, when the causes of social demographic properties influencing childbirth was analyzed, sex showed significance to all the factors on the hoping number of children in terms of growing areas, to all the factors excluding childbirth policy in terms of the economic level, and hoping number of children in terms of the parents' jobs. Third, when the correlation was analyzed, a correlation was found in every area excluding the hoping number of children in terms of the causes of childbirth reduction and economy, childbirth policy in terms of the personal causes, personal factor in terms of the causes of childbirth policy, and family factor in terms of the causes of childbirth reduction and economy. Fourth, when the influences of the causes of hoping number of children, childbirth policy, and childbirth reduction to perception of childbirth were analyzed, the case hoping no or one child, the case hoping 2 or more children, childbirth policy, and childbirth reduction had a positive significant influence on the perception of childbirth. Conclusion: The childbirth rate will be improved if the following occur: childbirth policy and laws are established at the level of government, education programs are developed and operated for the formation of the value of perception of childbirth, and a new support policy is established after analyzing the current childbirth support policies. To change the perception of childbirth in college students who are future subjects of childbirth, successive studies will be needed to verify the effect of aforesaid measures.

A Study on the actual conditions of the use of them and the moves to strengthen home economics resources for school lifelong education in home economics teachers' view (가정과교사가 인식한 학교 평생교육을 위한 가정과 자원의 활용 실태 및 활성화 방안)

  • Kim, Sung-Hee;Chae, Jung-Hyun
    • Journal of Korean Home Economics Education Association
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    • v.18 no.4 s.42
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    • pp.127-141
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    • 2006
  • The purpose of this study was to investigate the actual conditions of the use of them and the moves to strengthen home economics resources for school lifelong education for parents and local residents. This study conducted a systematic random sampling. Questionnaires were distributed to home economics teachers from 285 middle schools, 123 high schools, and 130 of them were sampled as the subjects of this study. The results of this study were as follows. First, home economics teachers were active participating school lifelong educational program. But according to the result of research on the actual condition, the proportion of taking part in it was low. More than half of home economics teachers who took part in program's lecturer were in charge of computer courses. So they didn't show their ability as expert. Also they were in charge of several works than roll of lecturers. It was mentioned too great a burden. There is little in-service training for meeting specialization for school lifelong education. They wanted to take part of lecturers of program and preferred hours of being over class. More than half of them had intended to obtain a lifelong educator's license. The part of elective courses for obtaining a lifelong educator's license is similar to home economics educational contents. So, they have an advantage of obtaining it. Second, one-fifth of school that gave school life education carried out program of related home economics. Mostly they had mothers of students-oriented programs on artistic and leisure. But this is that home economics teachers mentioned less important teaching at society in the future. They importantly mentioned program on children's education in now and the future. Parents of students and local residents also extremely wanted it. For differentiated school life education, quality of programs is important greatly. Third, the actual condition of practical room relating home economics is only practice to cook mostly. So they are reluctant to be open it because of being responsible for the results from using there. It is necessary to ameliorate there's facilities and to increase there's area. Fourth, home economics teachers want to improve their specialization through in-service training, to develop and diffuse programs of superior quality, and to get extra pay for overtime from the government.

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A study of Establishment on Radiomap that Utilizes the Mobile device Indoor Positioning DB based on Wi-Fi (Wi-Fi 기반 모바일 디바이스 실내측위 DB를 활용한 라디오맵 구축에 관한 연구)

  • Jeong, In Hun;Kim, Chong Mun;Choi, Yun Soo;Kim, Sang Bong;Lee, Yun
    • Journal of Korean Society for Geospatial Information Science
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    • v.22 no.3
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    • pp.57-69
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    • 2014
  • As of 2013, Korean population density is 505 persons per $1km^2$ and is ranked 3rd place in the most densely populated countries exception of city-states. It shows clearly the population is concentrated in the city area. To fulfil this urban concentration population demand, the enlargement and complexation of buildings, subway and other underground spaces connection tendency has been intensified, and it is need to construct the indoor spatial information DB as well as the accurate indoor surveying DB to promote people's safety and social welfare. In this study, Sadang station and Incheon National Airport were aimed for the construction of Wi-Fi AP location DB and RadioMap DB by collecting the indoor AP raw datas by using mobile device and those collected results were ran through the process of verification, supplementation, and analyzation. To evaluate the performance of constructed DB, 10 points in Incheon Airport- 3rd flr in block A, and 9 points in Sadang station-B1 were selected and calculated the estimated points and ran evaluation experiment using survey positioning error, which is distance between real position and the estimated position. The result shows that Incheon international airport's average and standard deviation was separately 17.81m, 17.79m and Sadang station's average and standard deviation was separately 22.64m, 23.74m. In Sadang station's case, the areas near the exit has low performance of surveying position due to fewer visible AP points than other areas. As total datas were examined except those position, it was verified that the user's location was mapping close position in surveying positioning by using constructed DB. It means that constructed DB contains correct Wi-Fi AP locations and radio wave patterns in object region, so it is considered that the indoor spatial information service based on constructed DB would be available.

Formation Process and Its Mechanism of the Sancheong Anorthosite Complex, Korea (산청 회장암복합체의 형성과정과 그 메커니즘)

  • Kang, Ji-Hoon;Lee, Deok-Seon
    • Economic and Environmental Geology
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    • v.48 no.6
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    • pp.431-449
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    • 2015
  • The study area is located in the western part of the Precambrian stock type of Sancheong anorthosite complex, the Jirisan province of the Yeongnam massif, in the southern part of the Korean Peninsula. We perform a detailed field geological investigation on the Sancheong anorthosite complex, and report the characteristics of lithofacies, occurrences, foliations, and research formation process and its mechanism of the Sancheong anorthosite complex. The Sancheong anorthosite complex is classified into massive and foliation types of Sancheong anorthosite (SA), Fe-Ti ore body (FTO), and mafic granulite (MG). Foliations are developed in the Sancheong anorthosite complex except the massif type of SA. The foliation type of SA, FTO, MG foliations are magmatic foliations which were formed in a not fully congealed state of SA from a result of the flow of FTO and MG melts and the kinematic interaction of SA blocks, and were continuously produced in the comagmatic differentiation. The Sancheong anorthosite complex is formed as the following sequence: the massive type of SA (a primary fractional crystallization of parental magmas under high pressure)${\rightarrow}$ the foliation type of SA [a secondary fractional crystallization of the plagioclase-rich crystal mushes (anorthositic magmas) primarily differentiated from parental magmas under low pressure]${\rightarrow}$the FTO (an injection by filter pressing of the residual mafic magmas in the last differentiation stage of anorthositic magmas into the not fully congealed SA)${\rightarrow}$the MG (a solidification of the finally residual mafic magmas). It indicates that the massive and foliation types of SA, the FTO, and the MG were not formed from the intrusion and differentiation of magmas which were different from each other in genesis and age but from the multiple fractionation and polybaric crystallization of the coeval and cogenetic magma.

Association Between the Polymorphism on Intron 5 of the Lipoprotein Lipase Gene and Carcass Traits in Hanwoo (Korean cattle) (한우 Lipoprotein Lipase 유전자 Intron 5번의 Polymorphism과 경제 형질과의 관련성 분석)

  • Lee, H.J.;Lee, S.H.;Cho, Y.M.;Yoon, H.B.;Jeon, B. K.;Oh, S.J.;Kwon, M.S.;Yoon, D.H.
    • Journal of Animal Science and Technology
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    • v.46 no.6
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    • pp.947-956
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    • 2004
  • The primary role of lipoprotein lipase(LPL) is the hydrolysis of triglycerides(TG) from the core of triglyceride-rich lipoproteins such as chylomicrons and very low density lipoproteins in plasma. Fatty acids liberated by LPL on capillary endothelial surfaces are available for tissues as energy sources especially in muscles or for storage in the form of TG in adipose tissues. Therefore, as the candidate gene related to the carcass traits of the beef cattle, we have directly sequenced the exon 5${\sim}$exon 6 region in the bovine LPL gene for discovery of single nucleotide polymorphism(SNP) with 24 unrelated Hanwoo(Korean cattle). Novel eight sequence variants were detected: three loci on exon 5, three on intron 5 and two on exon 6. All SNPs identified were strongly linked each other, and one hundred twenty eight Hanwoo samples were genotyped one SNP on intron 5 using PCR-restriction fragment length polymorphism method by digestion with Hae III restriction enzyme. The allele frequency of the polymorphism was 0.76 and 0.24. The effects of this polymorphism on the breeding values of the carcass weight, loin muscle area, back fat thickness and marbling score were analyzed using least square methods of SAS GLM. The marbling score of BB genotype was significantly higher than those of AA and AB genotypes(P<0.05). This result indicates that this polymorphism may be associated with the variation of marbling score. Further study is warranted to investigate the phenotypic association in Hanwoo.

Uptake and Translocation of Heavy Metals to Rice Plant on Paddy Soils in "Top-Rice" Cultivation Areas (탑라이스 생산지역 논 토양 중 잔류중금속의 벼 흡수이행)

  • Park, Sang-Won;Yang, Ju-Seok;Ryu, Seung-Won;Kim, Dae-Yeon;Shin, Joung-Du;Kim, Won-Il;Choi, Ju-Hyeon;Kim, Sun-Lim;Saint, Andrew Flynn
    • Korean Journal of Environmental Agriculture
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    • v.28 no.2
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    • pp.131-138
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    • 2009
  • Heavy metal residues in soil, rice straw, unhulled rice, rice hull, polished rice, and rice barn on the rice paddy in the "Top rice production complex which is non-contaminated area were evaluated. It was observed that the average concentrations of As, Cd, Cu, Pb, and Hg in the paddy soils were 1.235, 0.094, 4.412, 4.728 and 0.0279 mg/kg, respectively. There were no cultivation areas exceeded of the threshold for soil contamination designated by "The Soil Environment Conservation Law" in Korea. For the polished rice, there were no samples exceeded of a permissible level of heavy metal residues such as 0.051 mg/kg of As, 0.040 mg/kg of Cd, 0.345 mg/kg of Cu, 0.065 mg/kg of Pb and 0.0015 mg/kg of Hg. For the uptake and translocation of heavy metals to rice plant, a main part of heavy metal accumulation was rice straw, and then rice bran. Furthermore, it shown that accumulation of heavy metals in unhulled rice, rice hulls, brown rice, and polished rice was approximately similar as low. The slopes of translocation of heavy metals from soil to polished rice were following order as Cd, 0.4321 > Cu, 0.054 ${\fallingdotseq}$ Hg, 0.052 > As, 0.021 > Pb, 0.008. It was observed that potential ability of Cd uptake in rice plant and then its translocation into polished rice was very high. Concentrations of copper and mercury absorbed in the rice plant were moderate for translocating into the polished rice, while the arsenic and lead in the plant were scarcely translocated into the polished rice. The distribution of heavy metals absorbed and translocated into aboveground parts of rice plant was appeared that there were remained at 63.3-93.4% in rice straw, 6.6-36.9% in unhulled rice, 0.6-5.7% in rice hulls, 3.2-31.3% in brown rice, 0.8-4.6% in rice bran and 1.1-26.7% in polished rice. The accumulation ratio of Cd in the aboveground parts of rice plant was remained at 26.7-31.3% in brown and polished rice.