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중등학교 과학교사들의 공통과학 교사자격증 유무에 따른 통합과학교육과 지속가능발전교육에 대한 인식 (Awareness of Integrated School Education and Education for Sustainable Development of Science Teachers in Secondary Schools with or without Common Science Teacher Qualification)

  • 지덕영
    • 대한지구과학교육학회지
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    • 제12권3호
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    • pp.224-238
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    • 2019
  • 본 연구의 목적은 중등학교 과학교사들의 공통과학 교사자격증 유무가 공통과학 지도의 전문성과 관련이 있다고 보고, 이에 따른 통합과학교육과 지속가능발전교육에 대한 인식을 분석하는 데 있다. 이를 위해 중등학교 과학교사를 대상으로 2018년 6월부터 8월까지 3달간 설문조사를 하였고, 객관식 문항은 통계처리를, 서술형 문항은 토픽모델링으로 분석하였다. 분석 결과, 공통과학 교사자격증을 가진 교사들이 통합과학교육에 대한 인지도가 높았으며, 통합과학교육의 가치, 방향, 성공조건의 모든 영역에서 응답 평균이 높은 것으로 분석되었다. 또한, 지속가능발전교육의 인지도 및 과학교육과의 통합 필요성 및 통합 의향의 응답 평균도 공통과학 교사자격증을 가진 교사들이 그렇지 않은 교사들에 비해 높은 것으로 분석되었다. 과학교육과 지속가능발전교육의 통합 시 강점에 대해서는 두 집단 간의 큰 인식 차이는 없었으나, 공통과학 교사자격증을 소지한 교사는 그렇지 않은 교사에 비해 모든 Topic에서 과학을 중심으로 두고 과학을 각 Topic의 매개체로 인식하고 있다는 차이를 보였다.

Bioassay on Natural Herbicidal Potential in Common Thistle (Cirsium pendulum Fisch.)

  • Chon, Sang-Uk
    • 한국작물학회지
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    • 제51권1호
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    • pp.101-106
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    • 2006
  • Common thistle contains water-soluble substances that are phytotoxic to neighboring plant species. A series of aqueous extracts from leaves, stems, roots and flowers of common thistle (Cirsium pendulum Fisch.) were assayed against alfalfa (Medicago sativa) seedlings to determine their allelopathy, and the results showed highest inhibition in the extracts from flowers and leaves, and followed by stems, and roots. The extracts at 40 g dry tissue $L^{-1}(g\;L^{-1})$ applied on filter paper in a Petri-dish significantly inhibited root growth of test plant by 87%. Methanol extracts at 100 g $L^{-1}$ from leaves inhibited root growth of alfalfa and barnyardgrass (Echinochloa crus-galli) by 89 and 98%, respectively. Hexane and ethylacetate fractions of common thistle reduced alfalfa root growth more than did butanol and water fractions. Incorporation into soil with the leaf residues at $100g\;kg^{-1}$ inhibited shoot fresh weights of barnyardgrass and eclipta (Eclipta prostrate) by 88 and 58%, respectively, showing higher sensitivity in grass species. These results suggest that common thistle plants had allelopathic potential for eco-friendly vegetation management, and that especially their activities were differently exhibited depending on plant part.

Multivariate Characterization of Common and Durum Wheat Collections Grown in Korea using Agro-Morphological Traits

  • Young-ah Jeon;Sun-Hwa Kwak;Yu-Mi Choi;Hyemyeong Yoon;Myoung-Jae Shin;Ho-Sun Cheon;Sieun Choi;Youngjun Mo;Chon-Sik Kang;Kebede Taye Desta
    • 한국작물학회지
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    • 제68권4호
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    • pp.343-370
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    • 2023
  • Developing improved wheat varieties is vital for global food security to meet the rising demand for food. Therefore, assessing the genetic diversity across wheat genotypes is crucial. This study examined the diversity of 168 durum wheat and 47 common wheat collections from 54 different countries using twelve agro-morphological parameters. Geumgang, a prominent Korean common wheat variety, was used as a control. Both qualitative and quantitative agronomical characteristics showed wide variations. Most durum wheats were shown to possess dense spikes (90%), while common wheats showed dense (40%) or loose (38%) spikes, with yellowish-white being the dominant spike color. The majority of the accessions were awned regardless of wheat type, yellowish-white being the main awn color. White or red kernels were produced, with white kernels dominating in both common (74%) and durum (79%) wheats. Days to heading (DH) and days to maturity (DM) were in the ranges of 166-215 and 208-250 days, respectively, while the culm length (CL), spike length (SL), and awn length (AL) were in the ranges of 53.67-163, 5.33-18.67, and 0.50-19.00 cm, respectively. Durum wheats possessed the shortest average DH, DM, and SL, while common wheat had the longest CL and AL (p < 0.05). Common wheats also exhibited the highest average one-thousand-kernel weight. Hierarchical cluster analysis, aided by principal component analysis, grouped the population into seven clusters with significant differences in their quantitative variables (p < 0.05). In conclusion, this research revealed diversity among common and durum wheat genotypes. Notably, 26 durum wheat and 17 common wheat accessions outperformed the control, offering the potential for developing early-maturing, high-yielding, and lodging-resistant wheat varieties.

Genetic Diversity of Wild Quail in China Ascertained with Microsatellite DNA Markers

  • Chang, G.B.;Chang, H.;Liu, X.P.;Zhao, W.M.;Ji, D.J.;Mao, Y.J.;Song, G.M.;Shi, X.K.
    • Asian-Australasian Journal of Animal Sciences
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    • 제20권12호
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    • pp.1783-1790
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    • 2007
  • The genetic diversity of domestic quail and two wild quail species, Japanese (Coturnix coturnix)and Common quail (Coturnix japonica), found in China was studied using microsatellite DNA markers. According to a comparison of the corresponding genetic indices in the three quail populations, such as Polymorphism Information Content (PIC), Mean Heterozygosity ($\bar{H}$) and Fixation Index, wild Common quail possessed rich genetic diversity with 4.67 alleles per site. Its values for PIC and $\bar{H}$ were the highest, 0.5732 and 0.6621, respectively. Domestic quail had the lowest values, 0.5467 and 0.5933, respectively. Wild Japanese quail had little difference in genetic diversity from domestic quail. In addition, from analyses of the fuzzy cluster based on standard genetic distance, the similarity relationship matrix coefficient between wild Japanese quail and domestic quail was 0.937, and that between wild Common quail and domestic quail was 0.783. All of these results showed that the wild Japanese quail were closer to the domestic quail for phylogenetic relationship than wild Common quail. These results at the molecular level provide useful data about quail's genetic background and further supported the hypothesis that the domestic quail originated from the wild Japanese quail.

Analysis of Phenolic Compounds in Sorghum, Foxtail Millet and Common Millet

  • Jeon, Hyun-Seok;Chung, Ill-Min;Ma, Kyung-Ho;Kim, Eun-Hye;Yong, Soo-Jung;Ahn, Joung-Kuk
    • 한국작물학회지
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    • 제56권4호
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    • pp.361-374
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    • 2011
  • The cereal grain crops have strong flexibility against adverse environment and they have various functional compounds. The objective of the present study was to screen phenolic compounds in sorghum [Sorghum bicolor (L.) Moench], foxtail millet (Setaria italica), common millet (Panicum miliaceum L.) by high performance liquid chromatography (HPLC) with photodiode array (PDA) detector. Sorghum contained the highest amount of phenolic compounds among three different crops (sorghum, foxtail millet, common millet). Especially Moktaksusu showed the highest amount of phenolic compounds concentrations and biggest regional differences. The comparison of average phenolic compounds in sorghums by regions showed order to Milyang ($963.3\;{\mu}g{\cdot}g^{-1}$), Yeongyang ($923.1\;{\mu}g{\cdot}g^{-1}$), Gijang ($831.3\;{\mu}g{\cdot}g^{-1}$) and Bonghwa ($735.6\;{\mu}g{\cdot}g^{-1}$). Among the sorghum cultivars, Moktaksusu ($1407.9\;{\mu}g{\cdot}g^{-1}$) had the highest concentration of phenolic compounds. The average phenolic compounds of foxtail millets showed similar amount among Milyang ($319.0\;{\mu}g{\cdot}g^{-1}$), Gijang ($288.1\;{\mu}g{\cdot}g^{-1}$) and Bonghwa ($281.9\;{\mu}g{\cdot}g^{-1}$) areas. The phenolic compounds of Yeongyang ($246.6\;{\mu}g{\cdot}g^{-1}$) slightly low and that showed similar concentrations among three different regions. The concentration of phenolic compounds in foxtail millets, Chungchajo ($335.6\;{\mu}g{\cdot}g^{-1}$) showed the highest concentrations. The average phenolic compounds of common millets showed the highest concentrations in Milyang ($305.5\;{\mu}g{\cdot}g^{-1}$), Bonghwa ($262.0\;{\mu}g{\cdot}g^{-1}$), Gijang ($195.1\;{\mu}g{\cdot}g^{-1}$), Yeongyang ($237.2\;{\mu}g{\cdot}g^{-1}$) in decreasing order. The concentration of phenolic compounds of common millets was the highest in the Norangchalgijang ($337.0\;{\mu}g{\cdot}g^{-1}$), Hwanggumgijang ($250.0\;{\mu}g{\cdot}g^{-1}$) was also relatively higher than others. The results of this study will provide basic information for breeding sorghums, foxtail millets and common millets with higher phenolic compound concentrations.

돼지풀이 작물과 잡초의 초기 생장에 미치는 Allelopathy 효과 (Allelopathic Effects of Common Ragweed (Ambrosia artemisifolia var. elatior) on the Germination and Seedling Growth of Crops and Weeds)

  • 최봉수;송득영;김충국;송범헌;우선희;이철원
    • 한국잡초학회지
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    • 제30권1호
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    • pp.34-42
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    • 2010
  • 돼지풀의 추출물에 의한 잡초의 발아와 토양혼입에 따른 작물 및 잡초의 초기생육을 조사하였다. 돼지풀의 잎 추출물은 줄기 및 뿌리 추출물보다 잡초의 발아를 억제시켰으며, 5%농도에서 돌피, 바랭이 및 금방동사니의 발아율은 각각 23.0, 19.5 및 9.2%로 대조구와 비교하여 각각 68.3, 74.7 및 87.3% 억제되었다. 이러한 경향은 돼지풀의 혼입에 의한 작물과 잡초의 출아율에서도 비슷하게 나타났는데 출아 억제효과는 돌피보다 바랭이와 금방동사니에서 보다 높은 것으로 나타났다. 그러나 돼지풀의 혼입은 콩과 옥수수의 출아에 영향을 미치지 않았다. 돼지풀의 잎 혼입량이 5%까지 증가함에 따라 돌피, 바랭이, 금방동사니의 초장은 대조구와 비교하여 각각 48, 63 및 66% 억제되었다. 돼지풀 혼입에 따른 잡초의 생육으로 돌피, 바랭이 및 금방동사니의 건물중은 대조구와 비교하여 각각 72, 78 및 71% 억제되었다.

COMMON FIXED POINT THEOREMS FOR WEAKLY COMPATIBLE MAPPINGS IN MENGER SPACES

  • Sharma, S.;Choubey, K.
    • 한국수학교육학회지시리즈B:순수및응용수학
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    • 제10권4호
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    • pp.245-254
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    • 2003
  • In this paper we prove common fixed point theorems for four mappings, under the condition of weakly compatible mappings in Menger spaces, without taking any function continuous. We improve results of [A common fixed point theorem for three mappings on Menger spaces. Math. Japan. 34 (1989), no. 6, 919-923], [On common fixed point theorems of compatible mappings in Menger spaces. Demonstratio Math. 31 (1998), no. 3, 537-546].

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저투입벼 재배에 관한 경영사례분석 (Economic Analysis on low Input Rice Cultivation)

  • 신용인;박주섭
    • 농업과학연구
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    • 제23권2호
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    • pp.285-300
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    • 1996
  • This study is aimed to provide data of low-input rice cultivation for agricultural policy, to reveal the problems of low-input cultivation through comparing the economic result of low-input cultivation with the common one, to search for solution or mitigation of the problems of low-input cultivation, and to forecast the future prospect of low-input rice cultivation. The following were the results obtained from the survey and analysis. The working hours per 10a inputted 45.4 hours which is 32% more than 34.5 hours of common cultivation. Yield per 10a was 355kg which was 101kg less than 456kg of common cultivation. But the farm received price per kg was 1,984.9 won which was 547.9 won more than 1,436.5 won of common cultivation. Gross receipts per 10a was 704,438 won which was higher than 655,044 won of common cultivation, and management cost was 230,820 won which slightly higher than 188,157 won of common cultivation. Consequently, the income of low-input rice cultivation was 473,617 won which somewhat exceed to 466,887 won of common cultivation.

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공통 및 고유부품으로 구성되는 제품의 부품공급을 위한 단일설비 일정계획 (Fabrication Scheduling of Products with Common and Unique Components at a Single Facility)

  • 윤상흠
    • 한국경영과학회지
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    • 제28권4호
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    • pp.105-114
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    • 2003
  • This paper considers a single facility scheduling problem for the fabrication of components supporting the subsequent assembly into products. Each product consists of two types of components, one is common to all products and the other is unique to itself. The unique components are processed individually and the common components are processed in batches, and a distinct setup is incurred for the production of a batch of common components. Under the so-called “batch availability” environment, we propose an efficient dynamic programming(DP) procedure for the optimal sequencing and batching schedule with minimum total completion times of products in the situation that each product is said to be complete if both common and unique components of the product are finished. Computational results show that the proposed DB procedure is more efficient than the previous work which has considered the same problem as this paper.

Structural Analysis of Black Common Bean (Phaseolus vulgaris L.) Anthocyanins

  • Choung, Myoung-Gun
    • Food Science and Biotechnology
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    • 제14권5호
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    • pp.672-675
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    • 2005
  • Two anthocyanins were isolated from 1% HCl-20% methanol extracts of KG 97287 black common bean (Phaseolus vulgaris L.) using semipreparative, high-performance liquid chromatography (HPLC). The anthocyanins were identified using a combination of LC/ES-mass spectrometry (MS) and spectroscopic methods of UV-Vis, $^1H-$ and $^{13}C-$ nuclear magnetic resonance (NMR). The chemical structures of these two anthocyanins were elucidated as delphinidin 3-glucoside and petunidin 3-glucoside and their contents in KG 97287 black common bean seed coats were determined to be $2.614{\pm}0.11$ and $0.167{\pm}0.01\;mg/g$, respectively. These contents were lower than reported internationally and we recommend the introduction into Korea of high anthocyanin varieties of black common bean.