• Title/Summary/Keyword: 대지

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ATPDraw Simulation for Transient Phenomena Analysis of Electrical Shock Underwater (수중 전격 과도현상 해석을 위한 ATPDraw 시뮬레이션)

  • Jung, Jong-Wook;Jung, Jin-Soo
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.21 no.6
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    • pp.48-54
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    • 2007
  • This paper describes the analysis of transient phenomena on the point that a human body suffers an electrical shock. A couple of case studies were discussed by using an ATPDraw simulation tool. Two models for the case studies were constructed on the assumption that the electrical shock event takes place under water to simulate the severest condition ; the first model that the human body contacts with an energized part exposed to water ; the second model that both hands and feet simultaneously contact with the ground under water. After modeling, the transient phenomena for the models were analyzed by comparing the voltages and currents calculated at each part of the human body. As a result steep front kicks in voltage and current were observed as transient phenomena on the point that the human body contacts with the energized part exposed to water in the first model and the magnitudes of the kicks considerably increased. It was considered however, the effect of the kicks due to the commercial power source on the human body could be neglected because the product of the current through the body and the short duration is less than the safety limit. When both hands and feet simultaneously contact with the ground in the second model, the voltage generally decreased all over the body parts, while the current flowing through the chest abruptly increased. The duration of this current was very shot, as well, thus its effect on the electrical shock is considered insignificant. After all, it was confirmed through the simulation results that the electrical shock depends on the magnitude in voltage and the body impedance.

A Comparative Study on Space Organization of Kindergarten in Korea and Japan (한국과 일본 유치원의 공간구성 실태 비교)

  • Park, Sung-Chul;Song, Byung-Joon;Cho, Jin-Il
    • The Journal of Sustainable Design and Educational Environment Research
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    • v.15 no.1
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    • pp.19-29
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    • 2016
  • This study aims to find a direction for desirable space organization in future Korean kindergartens by analyzing the current status of space organization in Japanese kindergartens. This study includes comparisons and analyses of Korean and Japanese curricula, facility standards on the national level and standards of national subsidy, current numbers of kindergarteners and preschoolers, and changes in kindergarten facilities over the last 5 years. Six kindergartens each in Korea and Japan, which were constructed after 2011 or are recommended as being good in space organization and kindergarten planning, are selected. The contents of space organization analysis are 'entry and placement, outdoor space', 'space program,' and 'plan design and organization of unit space'. In conclusion, in terms of space organization, Korean and Japanese kindergartens are very similar to each other. However, Japanese kindergartens have more outdoor space about $9.75m^2$ and lot area about $11.89m^2$ than Korean kindergartens. The extra space was used to educate students in various contents regarding social network and physical activity. Furthermore, in Japan, special spaces such as "atelier classes" and "PTA" were used for various types of education. Based on the results of the study will be developed, such as specific models and guidelines for the improvement of facilities Korea kindergarten.

Volcanic Processes of Dangsanbong Volcano, Cheju Island (제주도 당산봉 화산의 화산과정)

  • 황상구
    • The Journal of the Petrological Society of Korea
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    • v.7 no.1
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    • pp.1-14
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    • 1998
  • Dangsanbong volcano, which is located on the coast of the western promontory of Cheju Island, occurs in such a regular pattern on the sequences which represent an excellent example of an eruptive cycle. The volcano comprises a horseshoe-shaped tuff cone and a younger nested cinder cone on the crater floor, which are overlain by a lava cap at the top of the cinder cone, and wide lava plateau in the moat between two cones and in the northern part. The volcanic sequences suggest volcanic processes that start with Surtseyan eruption, progress through Strombolian eruption and end with Hawaiian eruption, and then are followed by rock fall from sea cliff of the tuff cone and by air fall from another crater. It is thought that the eruptive environments of the tuff cone could be mainly emergent because the present cone is located on the coast, and standing body of sea water could play a great role. It is thought that the now emergent part of the tuff cone was costructed subaerially because there is no evidence of marine reworking. The emergent tuff cone is characterized by distinctive steam-explosivity that results primarily from a bulk interaction between rapidly ascending magma and external water. The sea water gets into the vent by flooding accross or through the top or breach of northern tephra cone. Dangsanbong tuff cone was constructed from Surtseyan eruption which went into with tephra finger jetting explosion in the early stage, late interspersed with continuous upruch activities, and from ultra-Surtseyan jetting explosions producting base surges in the last. When the enclosure of the vent by a long-lived tephra barrier would prevent the flooding and thus allow the vent to dry out, the phreatomagmatic activities ceased to transmit into magmatic activity of Strombolian eruption, which constructed a cinder cone on the crater floor of the tuff cone Strombolian eruption ceased when magma in the conduit gradually became depleted in gas. In the Dangsanbong volcano, the last magmatic activity was Hawaiian eruption which went into with foundation and effusion of basalt lava.

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Tuber Yield and Size Distribution of Potato 'Dejima' (Solanum tuberosum L.) Affected by Stem Cutting Ages and Harvest Time in Aeroponics (경삽묘 연령과 수확시기가 분무경재배 씨감자 '대지'의 생육과 수량에 미치는 영향)

  • Chae, Won-Byoung;Ahn, Seung-Joon;Choi, Hak-Soon;Kwack, Yong-Bum;Goo, Dae-Hoe;Jeong, Myeong-Il
    • Journal of Bio-Environment Control
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    • v.17 no.4
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    • pp.261-265
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    • 2008
  • This study was carried out to investigate the effects of stem cutting ages and harvest time on the growth and yield of potato 'Dejima' in aeroponics. The stem cuttings were produced from in vitro plantlets and transplanted into an aeroponic system with 20, 30, 40 and 50 day-old stem cuttings (DOS). Tubers were harvested 60, 70, 80 and 90 days after transplanting (DAT) and sorted into following categories: $1{\sim}5$, $5{\sim}10$, $10{\sim}20$, $20{\sim}30$, $30{\sim}40$ and over 40 g. Plant height from the 40 DOS was the highest during the growing periods but no significant difference was observed on 75 DAT. The tuber weight increased until 90 DAT with the greatest weight of tubers in the 20 and 40 DOS. However, there was no significant difference among 20, 30 and 40 DOS in the number and weight of tubers. Harvesting at 80 and 90 DAT increased the number of tubers over 5 g, which are usually considered as appropriate for direct field planting.

Myth of 61.8% rule and the practical application notices (접지저항 측정의 61.8%법칙 적용의 맹점과 현실적 접근 방법)

  • Lee, Sang-Mu;Cho, Pyung-Dong
    • 한국정보통신설비학회:학술대회논문집
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    • 2005.08a
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    • pp.259-262
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    • 2005
  • Ground resistance measurement is an elementary technique for the evaluation of grounding system. There are main environmental factors to consider for correct measurement but the problem is that it is practically most cases to measure ground resistance unable to know the factors. This paper presents a methodology toward true value of resistance in the unknown circumstances, utilizing the defined term 'variation rate' of potential difference curve appearing in the distance to a current probe as in the three point fall-of-potential method which comprises the characteristics of environmental factors. This methodology is a induced result from the previous demostrated studies.

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A Study on the Safety Grounding for Prevention of Electric Shock Hazard in Construction of Industrial Plant in Maritime Landfill Area (해상 매립 지역 산업 플랜트 건설 시 감전 재해 예방을 위한 안전 접지에 관한 연구)

  • Kim, Hong-Yong;Jang, Ung-Burm
    • Journal of the Society of Disaster Information
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    • v.13 no.3
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    • pp.305-312
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    • 2017
  • In our society, the advanced, advanced, and information industries have continued to grow and now live in the era of the fourth industrial revolution. As the industry develops, the load of the users has also increased so much that it is deepened by the energy shortage phenomenon and the construction of additional energy facilities is required. Therefore, energy plant construction work is being actively carried out in the coastal area. In particular, it is common to build a plant in the ground by filling the coast with soil in other regions, reflecting the fact that Korea is lacking in the country when constructing power plants, gas and petrochemical plants. Current domestic grounding designs are designed or constructed to suit only the use of grounding resistors based on the electrical equipment design technical standards. However, in the case of a plant facility constructed in the untested buried soil, when the lightning current and the abnormal current are inputted, the facility operator or the user due to the elevation of the ground potential is seriously exposed to the risk of electric shock disaster. In this paper, we analyze the ground resistivity of the landfilled soil and use a computer program (CDEGS) based on KS C IEC 61936-1, We analyze the contact voltage and stratification voltage and propose a grounding design optimized for plant installation.

Analysis of Transient Potential Rises of Horizontal Ground Electrodes Considering the Frequency-Dependent of Soil (토양의 주파수의존성을 고려한 정보통신설비용 수평접지전극의 과도전위상승 분석)

  • Ahn, Chang Hwan
    • Journal of the Institute of Electronics and Information Engineers
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    • v.53 no.2
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    • pp.147-153
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    • 2016
  • The lightning protection of information and communication facilities is very important factor to improve a reliability of the action of these equipment. Especially the transient potential rise of ground electrode being injected with the lightning current is to be a basic data of the dielectric strength for both power and communication facilities so that more accurate analysis should be required. The transient potential rise can be calculated from the ground impedance and the ground impedance is strongly dependent upon the shape of the ground electrode and the frequency-dependence of soil. The Debye's equation which is able to calculate the characteristics of dielectrics is used to analyze the frequency-dependent of soil. Also, the method to calculate the transient potential rise from the ground impedance is specified in this paper. In order to analyze the transient potential rise resulting from calculations with Debye's equation, TLM(transmission line method) and case of ${\rho}$(resistivity)-constant are simulated, respectively. The length of a horizontal ground electrode is 30 m and simulations were performed at 10, 100, $1000{\Omega}{\cdot}m$ with the standard lightning current waveform. In result, the transient potential rise of horizontal ground electrode calculating with Debye's equation is lower than it of other models.

A Consideration on the Solitude in Nietzsche's Philosophy (고독에 관한 니체의 성찰)

  • Kim, Jae-chul;Gu, Bo-sang
    • Journal of Korean Philosophical Society
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    • v.142
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    • pp.51-74
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    • 2017
  • As the phrase 'solitude death' implies, solitude generally has a negative characteristic as an object to avoid. But on the contrary, Nietzsche attempts to accept solitude and even affirms it in his overall philosophy. This study is about the authentic meaning of Nietzsche's solitude concept, aiming to clarify what true meaning solitude has to Nietzsche. This study will examine the 'external situation that humans face today' first. To do this, the study will consider the situation that humans who lost the earth and homeland faced in the period when God is dead. This study will then look at 'memory' and 'oblivion', as human's internal situations. And following that, this study will examine what meaning 'creativity' has to Nietzsche, which has a close relationship with those internal situations. Lastly, the meaning that 'body' and 'dance' imply to Nietzsche and what relationship these have with true solitude will be presented. Human is the being who can not avoid solitude whether they want it or not. Even though we make whatever effort we can to run away, solitude is unavoidable. The smart phone that makes me feel emptiness when I don't hold it on my hands, the hobbies which attract and force us to do, and new products which make us feel lonely if we don't buy them, don't they prove these efforts? What meaning does solitude have to humans that we have no other way but to run away from it like this? By understanding the authentic meaning of Nietzsche's solitude concept, we can change our view point on solitude so we can eventually accept 'solitude' as something that we must truly embrace and affirm, instead of something we must run away from.

Nietzsche in the Square of Carlos Alberto (카를로스 알베르토 광장의 니체)

  • Lee, Wang-joo
    • Journal of Korean Philosophical Society
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    • v.142
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    • pp.221-241
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    • 2017
  • I try to elucidate the essence of cinematic art in terms of Nietzsche's physiological philosophy of art. According to Nietzsche, the mise-en-$sc{\grave{e}}nes$ in the film are expressions of willingness to the power of the author, the director. These are not re-imitations of the imitations with Platonic measure, sinker, number, but framing the elan vital Erde, die $urspr{\ddot{u}}ngliche$ Vorstellung with the director's body-camera. In this context, the film is essentially die Kunst des Lebens, in which the body and the earth are mediated by cameras. Therefore, it is not the eyes or the head, but the body that is necessary to appreciate film art. But the body at this time does not mean the heavy body of Hollywood standard audiences manipulated, controlled, or transformed by capital. We should stand in front of the film work with body shaking between trauma and Rausch, a dancing body, and a light and fresh body. Only by watching film with the body, can we achieve the small revolutions in everyday life. For example, if we watch $B{\acute{e}}la$ Tarr's film The Turin Horse in such a way, we can no longer be the dwarfed human beings, der Herde-Mensch. Also, $B{\acute{e}}la$ Tarr's mise-en-scene will make us realize why Nietzsche had said that there is art to us not to be destroyed by the platonic truth.

Geomorphology and Geology of Gatbawi, Mokpo, Korea (목포 갓바위의 지형 및 지질 특성과 활용)

  • Kim, Hai-Gyoung;Moon, Byoung-Chan;Koh, Yeong-Koo;Youn, Seok-Tai;Oh, Kang-Ho
    • Journal of The Geomorphological Association of Korea
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    • v.19 no.1
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    • pp.99-108
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    • 2012
  • To consider geomorphological and geological characteristics to Gatbawi(the 500th natural monument), it was investigated with the aspect of scale, form, mineralogy, chemistry and weathered state. Showing typically erosional features, micro-terrains as sea cliffs, sea notches, marine plateaus and tafoni developed well on coastal areas near the monument. Sea cliffs are vertical and form sea notches in their bases. Coastal terraces are 3.5m in width and 20m in trace. Tafoni are honey combed. The monument is mainly composed of quartz, plagioclase, microcline, biotite, sericite in mineral and corresponded to crystalline tuff dominated in quartz and plagioclase. It has 23.60~28.27 wt.% of $Al_2O_3$, 3.27~5.80 wt.% of $Na_2O$, and 0.11~0.20 wt.% of Cl in chemical contents, leveling higher than those of earth crust standards. It is considerably weathered on the basis of CAI(77.42~83.93%). The monument is very useful for natural perspective tourism and education. Therefore, it is necessary that several ideas as guide plates, observing telescope, explaining guider, education programs connected with related services, touring goods, picture for books on utilization on the monument must establish.