• Title/Summary/Keyword: 코일 중심

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Flow Resistance and Modeling Rule of Fishing Nets 3. Establishment of Modeling Rule and its Theoritical Examination (그물어구의 유수저항과 모형수칙 3. 모형수칙의 수립 및 이론적 검토)

  • KIM Dae-An
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.30 no.4
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    • pp.543-549
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    • 1997
  • The problems in the existing modeling rules for fishing nets, especially in the Tauti's rule which had been used most commonly, were investigated and it was found that the rules could not give a good similarity between the prototype and model nets because they din neither analyze the flow resistance of nets accurately nor decide the ratio of flow velocity between the two nets properly. Thus, the modeling rule was newly derived by regarding the nets as holey structures sucking water into their mouth and then filtering water through their meshes as in the previous paper. The similarity conditions obtained, between the two nets distinguished by subscript 1 and 2, are as follows; $$\frac{d_2}{d_1}=\sqrt{\frac{l_2}{l_1}},\;\frac{N_2}{N_1}=(\frac{d_1}{d_2})^{1.5}\frac{L_2}{L_1},\;\varphi_1=\varphi_2,\;\frac{d_{r2}}{d_{r1}}=\sqrt{\frac{L_2{(\rho_{r1}-\rho_{w1})}}{{L_1{(\rho_{r2}-\rho_{w2})}}$$ $$\frac{N_{a2}}{N_{a1}}=\frac{W_{a1}}{W_{a2}}(\frac{L_2}{L_1})^2,\;\nu_1=\nu_2\;and\;\frac{R_2}{R_1}=(\frac{L_2}{L_1})^2$$, where L is the length of nettings, d the diameter of netting twines, 2l the mesh size, $2\varphi$ the angle between two adjacent bars, N the number of meshes at the sides of nettings, $d_r$, the diameter of ropes, $\rho_r$, the specific gravity of ropes, $W_a$ the weight in water of one piece of float or sinker, $N_a$ the number of floats or sinkers, $\nu$ the flow velocity, and R the flow resistance of net. In the case where the model experiments aim at investigating the influence of weight in water of nettings on their shapes in nets subjected to the water flow of very low velocity, however, the following condition is added; $$\frac{\rho_2-\rho_{w2}}{\rho_1-\rho_{w1}}=\frac{d_1}{d_2}$$ where $\rho$ is the specific gravity of netting twines.

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The Influence of Pesticides on Some Chemical and Microbiological Properties Related to Soil Fertility -I. Effects of Herbicide (CNP) on Some Soil Chemical Factors Concerning Nitrogen Mineralization (농약제(農藥劑)의 시용(施用)이 토양(土壤)의 비옥성(肥沃性) 및 미생물상(微生物相)에 미치는 영향(影響) -I. CNP 시용(施用)이 토양(土壤)의 pH, Eh 및 질소무기화(窒素無機化)에 미치는 영향(影響))

  • Ryu, Jin-Chang;Araragi, Michio;Koga, Hiroshi
    • Korean Journal of Soil Science and Fertilizer
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    • v.16 no.4
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    • pp.372-381
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    • 1983
  • A laboratory experiment was performed to investigate the effects on redox potential of submerged soil by application of CNP herbicide (2, 4, 6-Trichlorophenyl-4-Nitrophenyl ether) with or without rice straw. Two soils, sandy loam and clay loam textured, were incubated for sixty days at a constant temperature, $25^{\circ}C$. Sampling and analysis of pH, Eh and nitrogen mineralization were carried out during the incubation. The results were summarized as follows. 1. The CNP application decreased redox potential and increased soil pH. The higher the concentration of applicated CNP was, the effects on soil Eh and pH were higher. When rice straw was used with CNP, the Eh of soil remarkably decreased, but seperating the individual effects of rice straw and CNP was impossible in this study. 2. Ammonification increased as the concentration of applied CNP increased regardless of rice straw application or not. It was higher in sandy loam soil than clay loam soil. 3. Nitrification decreased as the concentration of applied CNP increased, especially in the sandy loam soil. Rice straw application reduced nitrification.

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Autopoietic Machinery and the Emergence of Third-Order Cybernetics (자기생산 기계 시스템과 3차 사이버네틱스의 등장)

  • Lee, Sungbum
    • Cross-Cultural Studies
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    • v.52
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    • pp.277-312
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    • 2018
  • First-order cybernetics during the 1940s and 1950s aimed for control of an observed system, while second-order cybernetics during the mid-1970s aspired to address the mechanism of an observing system. The former pursues an objective, subjectless, approach to a system, whereas the latter prefers a subjective, personal approach to a system. Second-order observation must be noted since a human observer is a living system that has its unique cognition. Maturana and Varela place the autopoiesis of this biological system at the core of second-order cybernetics. They contend that an autpoietic system maintains, transforms and produces itself. Technoscientific recreation of biological autopoiesis opens up to a new step in cybernetics: what I describe as third-order cybernetics. The formation of technoscientific autopoiesis overlaps with the Fourth Industrial Revolution or what Erik Brynjolfsson and Andrew McAfee call the Second Machine Age. It leads to a radical shift from human centrism to posthumanity whereby humanity is mechanized, and machinery is biologized. In two versions of the novel Demon Seed, American novelist Dean Koontz explores the significance of technoscientific autopoiesis. The 1973 version dramatizes two kinds of observers: the technophobic human observer and the technology-friendly machine observer Proteus. As the story concludes, the former dominates the latter with the result that an anthropocentric position still works. The 1997 version, however, reveals the victory of the techno-friendly narrator Proteus over the anthropocentric narrator. Losing his narrational position, the technophobic human narrator of the story disappears. In the 1997 version, Proteus becomes the subject of desire in luring divorcee Susan. He longs to flaunt his male egomaniac. His achievement of male identity is a sign of technological autopoiesis characteristic of third-order cybernetics. To display self-producing capabilities integral to the autonomy of machinery, Koontz's novel demonstrates that Proteus manipulates Susan's egg to produce a human-machine mixture. Koontz's demon child, problematically enough, implicates the future of eugenics in an era of technological autopoiesis. Proteus creates a crossbreed of humanity and machinery to engineer a perfect body and mind. He fixes incurable or intractable diseases through genetic modifications. Proteus transfers a vast amount of digital information to his offspring's brain, which enables the demon child to achieve state-of-the-art intelligence. His technological editing of human genes and consciousness leads to digital standardization through unanimous spread of the best qualities of humanity. He gathers distinguished human genes and mental status much like collecting luxury brands. Accordingly, Proteus's child-making project ultimately moves towards technologically-controlled eugenics. Pointedly, it disturbs the classical ideal of liberal humanism celebrating a human being as the master of his or her nature.

Entertainment History Perspective - Around the Grand Duchess to Appear in Movies 'Elizabeth' - (엔터테인먼트 관점에서 바라본 영화로 본 역사 - 영화 '엘리자베스'에 나와 있는 여성 통치자에 대한 관점을 중심으로 -)

  • Choi, Sun-Ah
    • Journal of Korea Entertainment Industry Association
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    • v.13 no.6
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    • pp.247-256
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    • 2019
  • The importance of the convergence education is getting more and more emphasized. But the university convergence education has not yet met today's needs. So this study is focused on showing effective practice methods and finding development directions of the university convergence criticism education. One of a significant trend of the contemporary academic education of liberal arts is the tendency of the convergent and integrative studies. What is essential in the convergent and integrative studies creativity. The zeitgeist of knowledge-based society is change and innovation. In response to its request, college education is being asked to do convergence education, And general education as the basis of convergence education is strengthened.