• Title/Summary/Keyword: 깔때기형

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Analysis of Pattern of Mathematical Interaction Occurring in the Elementary School Mathematics Classrooms (초등학교 수학교실에서 나타난 수학적 의사소통 유형 분석)

  • Cho, Young-Jun;Shin, Hang-Kyun
    • Journal of Elementary Mathematics Education in Korea
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    • v.14 no.3
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    • pp.681-700
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    • 2010
  • These days, the importance of the mathematics interaction is strongly emphasized, which leads to the need of research on how the interaction is being practiced in the math class and what can be the desirable interaction in terms of mathematical thinking. To figure out the correlation between the mathematical interaction patterns and mathematical thinking, it also classifies mathematical thinking levels into the phases of recognizing, building-with and constructing. we can say that there are all of three patterns of the mathematics interactions in the class, and although it seems that the funnel pattern is contributing to active interaction between the students and teachers, it has few positive effects regarding mathematical thinking. In other words, what we need is not the frequency of the interaction but the mathematics interaction that improves students' mathematical thinking. Therefore, we can conclude that it is the focus pattern that is desirable mathematics interaction in the class in the view of mathematical thinking.

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Improvement of Sea Eel Pots (붕장어 통발의 개량)

  • KO Kwan-SoH;KWON Byeong-Guk
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.20 no.2
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    • pp.95-105
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    • 1987
  • Traditional sea Eel pots can be divided into two groups such as bamboo and plastic pots, however they are nearly same in a shape with one entrance and fishing efficiency, except their materials. Very few yet have been studied on their catching methods or catching mechanisms at the view point of behavior. Accordingly, we have designed tubular pots in order to fill up faults of traditional fishing gear construction and behaviors of sea eel. The suitable tubular pots was decided by comparative experiments in the water tank and the fishing efficiency was compared through the field experiments. The results obtained are as follows : 1. The differences between traditional plastic pots and improved tubular pots are firstly two entrances in both ends of tube without holes, secondly flapper nets are fixed at the end of each cone, and thirdly a bait bag is fixed at the center of pot. 2. The standard size of the suitable tubular pot is: $$Tube\;:\;\phi\;12\~13{\times}L80\;cm$$, $$Cone\;:\;Inside\;ring\;\phi6{\times}D5\;cm$$, Flapper : L10 cm. 3. The fishing efficiency of tubular rots is 2.3 times better than that of plastic pots.

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Technologies Required for Development of Trap-based MAT Control Against the Striped Fruit Fly, Bactrocera scutellata (호박꽃과실파리의 트랩형 수컷박멸제 기반 기술 개발)

  • Kim, Kyusoon;Kim, Minhyun;Kwon, Gimyeon;Kim, Yonggyun
    • Korean journal of applied entomology
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    • v.56 no.1
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    • pp.51-60
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    • 2017
  • The striped fruit fly, Bactrocera scutellata, infests pumpkin flowers. Males are attracted to raspberry ketone (RK) and feed the attractant. This study was conducted to determine essential techniques to develop a male annihilation technique (MAT) of this insect pest. Effective attractants were screened in laboratory and field conditions. Both males and females were responsive to methyl eugenol (ME) in laboratory, though no flies were attracted to ME traps in field conditions. In contrast, cuelure (CL), which is a chemical derivative of RK, was effective to attract males of B. scutellata in both laboratory and field conditions. However, RK was equivalent or superior to CL when they were formulated in a form of wax dispenser. A pyrethroid insecticide along with the attractant was effective to attract and kill B. scutellata. Funnel trap was useful for MAT to confirm and count dead flies. These results indicate that MAT against B. scutellata consists of RK and bifenthrin in a wax type formulation, which is installed to a funnel type of trap. These essential factors would be useful to develop MAT applicable to control B. scutellata in fields.

A study on the free surface vortex in the pipe system (배관내 자유수면에서 와류현상에 대한 연구)

  • 오율권;장완호;이종원;김상녕
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.16 no.11
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    • pp.2126-2135
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    • 1992
  • In order to prevent the decay heat removal system from failure due to air entrainment or free surface vortex in the piping system, a set of simulating experiments for the midloop operation of nuclear power plant was performed. Through these experiments, a relation between the dimensionless numbers, such as submergence H/d, froude number, reynolds number, was found. However, the effect of reynolds number was negligible for the operation conditions of Nuclear power plant. It was also found that the perturbation of the system by the disturbance such as pump start, valve operation, etc., has a strong effect on the free surface vortex. Furthermore, from a view point of reactor safery, a modified inlet device of reducer type is strongly recommendable for the prevention of air entrainment.

Customer journey in the digital age (디지털 시대의 고객여정)

  • Chung, Byoung-gyu;Jung, Sang-hee
    • Journal of Venture Innovation
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    • v.1 no.1
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    • pp.29-47
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    • 2018
  • As the radical advances of digitalization, our daily life have been fundamentally changed. As a result, the customer journey also changed as compared with previous periods. This study analyzed customer journy of digital age. First, historical trends and issues of customer journey research were analyzed. Second, Comparative analysis of customer journey of digital and previous age were conducted. No more funnel model of customer journey which assumed hierarchical and linear paths was valid. Customer journey of digital age will be non-linear and circular paths.

Morphological Characteristics of the Fruiting Bodies of Wild Lentinula edodes Strains Cultivated on Sawdust Blocks in Korea (국내에서 수집한 야생 표고의 사각 톱밥배지 재배에서 자실체의 형태적 특성)

  • Yeun Sug Jeong;Min-Jun Kim;Eunjin Kim;Mi-Jeong Park;Kang-Hyeon Ka;Yeongseon Jang
    • The Korean Journal of Mycology
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    • v.51 no.4
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    • pp.429-440
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    • 2023
  • Wild Lentinula edodes (shiitake) strains are an important breeding material for developing new varieties suitable for various consumer preferences and environmental conditions. The morphological characteristics of 100 wild shiitake strains collected from 14 regions were investigated in a sawdust block cultivation. The characteristics of their fruiting bodies were diverse. Among them, 38% of the caps was convex, 33% was broadly umbonate, 27% was applanate, and 2% was shallowly depressed. In terms of their stipes, 55, 23, and 22% were the column, clavate, and funnel type, respectively. The shape of the cap was the most diverse on Mt. Hwaak, whereas the shape of the stipe showed various phenotypes from various regions. Even among strains collected from the same forest, different types of mushrooms were observed. In conclusion, wild shiitake strains that have adapted to various environmental stress can be used to develop new varieties. Thus, securing various genetic resources and studying their traits are important for researching breeding technology.

Volcanic Forms and Eruption Processes of Laoheishan and Huoshaoshan in the Wudalianchi Volcanics, NE China (중국 오대연지 라오헤이산과 후오샤오산의 화산 형태와 분출 과정)

  • Hwang S.K.;Jin X.;Ahn U.S.
    • The Journal of the Petrological Society of Korea
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    • v.14 no.4 s.42
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    • pp.251-263
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    • 2005
  • Modern volcanoes, Laoheishan and Huoshaoshan, have erupted during $1720\~1721$ in the Wudalianchi volcanic group, NE china. They comprise scoria and spatter cones that consist of potassium-rich phono-tephritic pyroclastic deposits and lavas, and include wide lava flow fields. The Laoheishan scoria cone is a polygenetic multiple volcano that overlaps earlier and later edifices with more complicated internal structures produced in greater scale and in earlier time than the Huoshaoshan. There is a funnel-shaped crater in the center of the later edifice of the Laoheishan scoria cone. The Huoshaoshan spatter cone is a monogenetic simple volcano with a central pit crater. The volcanic sequences indicate eruption processes that followed a repeated pattern that progressed through 5 stages of explosive and effusive eruption including lava fountains and Strombolian eruptions in the Laoheishan, and a recognizable pattern of 2 stages that started with Strombolian eruption and progressed through lava effusion in the Huoshaoshan.

Characteristics of a new cultivar Pleurotus ostreatus, Hwaseong #2 (신품종 느타리버섯 '화성2호'의 특성)

  • Lee, Jeong-Woo;Han, Yong-Sik;Han, Chul-Hee;Jeong, Chong-Chun
    • Journal of Mushroom
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    • v.9 no.3
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    • pp.96-100
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    • 2011
  • MST247ns(Hwaseong #2) was developed by the method of Di-mon mating between monokaryotic strains derived from "Hwaseong #1" and dikaryotic strain "Suhan #1". The optimum temperature of mycelial growth was $25-30^{\circ}C$. The optimum temperature of primordia formation and fruiting body development were $8-15^{\circ}C$ and $9-14^{\circ}C$. Days of primordia formation were 4-5 days later Suhan #1. The stipes were longer than "Suhan #1". The surfaces of stipe were white and the tissues got harder and more elastic. Therefore, the management of growth environment under low temperatures was relatively easy and storability got much better.

Characterization of a new commercial strain 'Gumbit' in Pleurotus cornucopiae var. citrinopileatus (노랑느타리 품종 '금빛'의 특성)

  • Yoo, Young-Bok;Kong, Won-Sik;Jang, Kab-Yeul;Kim, In-Yeup;Oh, Se-Jong;Jhune, Chang-Sung
    • Journal of Mushroom
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    • v.4 no.3
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    • pp.83-87
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    • 2006
  • A new commercial strain "Gumbit" of golden oyster mushroom was developed by hyphal anastomosis. It was improved with hybridization between monokaryotic strain derived from ASI 2295 and ASI 2703. The optimum temperature of mycelial growth and fruiting body development were $25{\sim}30^{\circ}C$ and $19{\sim}24^{\circ}C$, respectively. The pileus was golden to brilliant yellow color. Commercial strain "Gumbit" was not as prolific as the more commonly cultivated Pleurotus ostreatus in the conversion of substrate mass to mushrooms. However, cultivator can save money for mushroom growing on high-temperature season as like summer in Korea. Since picking individual mushrooms is tedious and often damages the fragile fruiting bodies compared with other species of oyster mushrooms.

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A taxonomic study of the genus Hosta in Korea (한국산 비비추속(Hosta Tratt.) 식물의 분류학적 연구)

  • Jo, Hyun;Kim, Muyeol
    • Korean Journal of Plant Taxonomy
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    • v.47 no.1
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    • pp.27-45
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    • 2017
  • A taxonomic study of the genus Hosta (Lilliaceae) in Korea was conducted based on morphological characteristics. Hosta clausa varieties share several characteristics (rhizomes with underground stolons, smooth scapes, and purple anthers). Hosta clausa var. normalis has an open perianth, long pistils, and fertile fruit. H. clausa var. clausa can be distinguished from H. clausa var. normalis by its closed perianth and sterile fruit. H. clausa var. geumgangensis has sterile fruit, green petioles, short pistils, and short narrow perianth tubes. H. clausa var. ensata has very narrow, sword-shaped leaves. It can be included in H. clausa var. normalis, which has a large degree of variation in leaf and petiole shape. H. jonesii has smooth scapes, yellow anthers, and bell-shaped flowers. It can be distinguished from the related species H. tsushimensis found on the Tushima islands in Japan by its wide perianth tube. H. yingeri is distinguished by its funnel-shaped flowers, 3 long and 3 short stamens, and smooth scape; the related species H. laevigata has 6 equally-sized stamens, narrowly lanceolate leaves, and wavy leaf margins. Because H. laevigata is not found in its type locality Isl. Heugsando, its taxonomic position must be determined at a later time. H. minor shares several characteristics (scapes with ridges and yellow-colored anthers) with the related taxa H. venusta. However, H. venusta is changed to H. minor var. venusta because it has overlapping characteristics in plant size, number of flowers, leaf size, and leaf shape. Consequently, the genus Hosta in Korea is classified into 5 species, 3 varieties, and 6 forms.