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A Study on the summer mortality of Korean rockfish Sebastes schlegeli in Korea (하절기 조피볼락, Sebastes schlegeli의 대량폐사에 관한 고찰)

  • Choi, Hye-Sung;Myoung, Jeong-In;Park, Myoung-Ae;Cho, Mi-Young
    • Journal of fish pathology
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    • v.22 no.2
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    • pp.155-162
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    • 2009
  • The mass mortality of Korean rockfish, Sebastes schlegeli that occured at the fish farms in Tongyeong and Geoje City regions between late August and early September in 2006 was investigated. Sixty two fish showed no significant external symptoms except ulcerative lesions with reddish foci on the skin. From the internal observations and diagnosis results, some yellowish brown liver, intestine bleeding, atrophy and congestion in the abdominal cavity of the fish were found. In the gill, swelled filaments caused by foreign material accumulation and mucus secretion were observed. However, the main cause of the fish mass mortality in both sampling regions could be due to physiological weakness induced by significant change of water temperature causing by typhoon Wookong during the summer in 2006.

A study on the design of tunnel lining insulation based on measurement of temperature in tunnel (터널 온도계측을 통한 라이닝 단열 설계에 관한 연구)

  • Kim, Dea-Young;Lee, Hong-Sung;Sim, Bo-Kyoung
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.13 no.4
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    • pp.319-345
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    • 2011
  • In case of tunnels in cold regions, a freeze of groundwater around tunnel may act as a barrier of tunnel drainage in winter, or may cause the inner extrusion of lining. In spite of that, a design of insulation for preventing the frost damage of tunnel lining has not been introduced in Korea, while foreign countries such as Norway and so on have a standard on insulation. In this study, a few freezing cases of road tunnels have been reviewed, and the results show that the freezing protection is necessary. In order to characterize the thermal distribution in the tunnel, following measurements have been performed at Hwa-ak tunnel; the temperature distribution by longitudinal lengths, the internal temperature of lining and the temperature distribution of the ground under pavement. From these measurements, the characteristics of the tunnel's internal temperature distribution due to temperature change in the air has been analyzed. Based on the measurement results on the temperature distribution at Hwa-ak tunnel, thermal flow tests on the rock specimen with and without insulation have been performed in the artificial climate chamber to investigate the performance of the insulation. Also, a number of 3D numerical analyses have been performed to propose appropriate insulation and insulation thicknesses for different conditions, which could prevent the frost damage of tunnel lining. As a result of the numerical analysis, air freezing index of 291$^{\circ}C{\cdot}$ Hr has been suggested as the threshold value for freezing criteria of groundwater behind the tunnel lining.

Habitual Fallacy or Intentional Propaganda: Understanding the Mechanism of Re-constructing North Korean Myth (관습적 오류 혹은 의도적 프로파간다: 북한관련 '의혹'의 실체적 진실과 담론 왜곡의 구조)

  • Kim, Sunghae;Lu, Liu;Kim, Tongkyu
    • Korean Journal of Legislative Studies
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    • v.23 no.1
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    • pp.187-226
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    • 2017
  • North Korea discourse is doubtful. A considerable portion is distorted under political objectives, group identity, and interests. Surely, there are facts based on North Korea's conducts. Apparent deceptions commonly exist as well though. Korean media does not endeavor to set the records straight and there are no revision towards mislead information. This is substantially dangerous as it can misjudge North Korean policies, beget national antipathy, and interferes with rational and constructive policy making. This study stems from such concerns and takes such cases as HEU(Highly Enriched Uranium) suspicion of 2002, dispute covering BDA(Banco Delta Asia)'s counterfeiting, and the abandonment of the Geneva Agreed Framework into consideration. The first part concentrates on fathoming the truth of the three cases. References from US government, academia, think tanks, media were inquired with an addition of secondary material from Korea and China. Secondly it examines whether domestic news properly reflects the precedent facts along the process of discovery. The cause and solution suggested by domestic media were organized and inductively reconstituted to frames. The last study questions the structural factors that reproduces suspicion analogs. Today's dangers facing Korean society are essentially not natural but artificial. This research hopes to foster peace by analyzing related discourses that are infamous to reinterpret reality.

Quantitative Risk Analysis for Railway Tunnels (철도터널 화재에 대한 정량적 위험도 분석)

  • Park, Jung Hyun;Shim, Cha Sang
    • Journal of the Korean Society for Railway
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    • v.20 no.3
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    • pp.400-412
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    • 2017
  • What is particularly noteworthy from Korean and foreign railway tunnel disaster prevention standards is that for the sake of rapid evacuation, more stringent standards for provision of evacuation passages, which require high cost, are being applied. Korean standards stipulate that passage installation should be determined in accordance with the level of risk through a QRA analysis of each tunnel with 1km or longer length. As, however, detailed application criteria as fire occurrence probability, fire occurrence scenario, size of fires and evaluation criteria for level of social risk are not available, additional costs may be incurred due to excessive design. Thus, standards of an appropriate level need to be established. With this backdrop, this study selects detailed application conditions of a reasonable and appropriate level through a study and analysis of relevant documents and analyzes the maximum length of tunnels to which the application of evacuation passages, or the application major evacuation promotion facilities, can be relaxed, together with a QRA analysis of model tunnels (for high speed rail) with different tunnel lengths. In addition, the QRA results on tunnels, including those on the Honam high-speed rail, and analysis results for the model tunnels, are compiled, ; the ultimate results are compared with Korean and other countries' standards related to evacuation promotion facilities, As a result, The appropriateness of application standards are reviewed. These results are expected to be utilized as basic material for establishing a reasonable disaster prevention plan that will consider safety and economies.

Biochemical Methane Potential of Agricultural Waste Biomass (농산 바이오매스의 메탄 생산 퍼텐셜)

  • Shin, Kook-Sik;Kim, Chang-Hyun;Lee, Sang-Eun;Yoon, Young-Man
    • Korean Journal of Soil Science and Fertilizer
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    • v.44 no.5
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    • pp.903-915
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    • 2011
  • Recently, anaerobic methane production of agricultural waste biomass has received increasing attention. Until now domestic BMP (Biochemical methane potential) studies concerned with agricultural waste biomass have concentrated on the several waste biomass such as livestock manure, food waste, and sewage sludge from WWTP (Waste water treatment plant). Especially, the lack of standardization study of BMP assay method has caused the confused comprehension and interpretation in the comparison of BMP results from various researchers. Germany and USA had established the standard methods, VDI 4630 and ASTM E2170-01, for the analysis of BMP and anaerobic organic degradation, respectively. In this review, BMP was defined in the aspect of organic material represented as COD (Chemical oxygen demand) and VS (Volatile solid), and the influence of several parameters on the methane potential of the feedstock was presented. In the investigation of domestic BMP case studies, BMP results of 18 biomass species generating from agriculture and agro-industry were presented. And BMP results of crop species reported from foreign case studies were presented according to the classification system of crops such as food crop, vegetables, oil seed and specialty crop, orchards, and fodder and energy crop. This review emphasizes the urgent need for characterizing the innumerable kind of biomass by their capability on methane production.

A study on the Composition of the Production Rates System to Prepare Standards for Calculating the Construction Cost of PC Structure Apartments Based on Off-Site Construction (OSC) (OSC 기반 PC구조 공동주택 공사비 산정기준 마련을 위한 품셈 체계 구성에 관한 연구)

  • Lee, Hansoo;Lee, Chiho;Lee, Jeongwook;Noh, Hyunseok
    • Korean Journal of Construction Engineering and Management
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    • v.22 no.6
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    • pp.96-106
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    • 2021
  • The PC structure based on the OSC (Off-Site Construction) is mentioned as a representative method of innovation in the construction industry that converts the existing construction environment from site-centered to factory production-transportation-site assembly. However, recent research on PC method has focused on improving the functions of subsidiary materials and improving the production system to increase productivity and institutional / policy R&D that can be universally applied to the life-cycle stage of ordering / design /construction is insufficient. In particular, the absence of standardized cost calculation standards makes it difficult to calculate and verify of objectified appropriate construction cost. So which is an obstacle to the activation of the PC method. In this study, the standards for construction costs of domestic and foreign PC method were surveyed and similar Construction Standard Production Rates were analyzed to confirm the product structure suitable for PC method. Subsequently, the construction procedures and input resources for each PC subsidiary materials were identified through on-site surveys to derive component for subsidiary materials, and the factors of change in the product according to the construction characteristics(height, weight of subsidiary material) were verified. As a result the standard product calculation system suitable for the site installation of the PC method for apartment was presented.

Compressive Strength Evaluation of Concrete with Mixed Plastic Waste Aggregates Filled with Blast Furnace Slag Fine Powder (무기충진재를 혼입한 복합 폐플라스틱 골재를 활용한 콘크리트 압축강도 특성)

  • Lee, Jun;Kim, Kyung-Min;Cho, Young-Keun;Kim, Ho-Kyu;Kim, Young-Wook
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.9 no.3
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    • pp.253-259
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    • 2021
  • Plastic wastes generated from household waste are separated by mixed discharge with foreign substances, and recycling is relatively low. In this study, the effect of the ratio and content of mixed plastic waste coarse aggregate(MPWCA)s and mixed plastic waste fine aggregate(MPWFA)s filled with blast furnace slag fine powder on the slump and compressive strength of concrete was evaluated experimentally. The MPWCAs were found to have a similar fineness modulus, but have a single particle size distribution with a smaller particle size compared to coarse aggregates. However, the MPWFAs were found to have a single particle size distribution with a larger fineness modulus and particle size compared to fine aggregates. Meanwhile, the effect of improving the density and filling pores by the blast furnace slag fine power was found to be greater in the MPWFA compared to the MPWCA. As the amount of the mixed plastic waste aggregate(MPWA)s increased, the slump and compressive strength of concrete decreased. In particular, the lower the slump and compressive strength of concrete was found to decrease the greater the amount of MPWFA than MPWCA when the amount of MPWA was the same. This is because of the entrapped air and voids formed under the angular- and ROD-shaped aggregates among the MPWFAs. On the other hand, the addition of the admixture and the increase in the unit amount of cement were found to be effective in improving the compressive strength of the concrete with MPWAs.

The Development Aspects of Korean Political Theatre Movement (한국 정치극의 전개 양상 - 1920년대부터 80년대까지의 정치극운동을 중심으로 -)

  • Kim, Sung-Hee
    • Journal of Korean Theatre Studies Association
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    • no.52
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    • pp.5-59
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    • 2014
  • This paper investigates the development and aesthetics of Korean political theatre from its quickening period 1920s to democratization era 1990s. Political theatre before 90s developed an antithesis resistant movement toward Korean modern history that had been scattered with suppressing political circumstances such as colonial era and dictatorial government, the movement has powerful activity and social influences. Just like the 20 century political theatre had been quickened under the influence of Marxism at Russia and Germany in 1920s, Korea's political theatre began in socialism theatre movement form around the same time. Proletarian theatre groups had been founded in Japan and Korea, and developed into practical movement with organized connection. However, the political theatre movement in Japanese colonial era was an empty vessel makes great sound but not much accomplishments. Most performance had been canceled or disapproved by suppression or censorship of the Japanese Empire. The political theatre in liberation era was the left drama inherited from Proletarian theatre of the colonial era. Korean Theatre alliance took lead the theatrical world unfold activities based on theatre popularization theory such as 'culture activists' taking a jump up the line and 'independent theatre' peeping into production spot as well as the important event, Independence Movement Day Memorial tournament theatre. Since 1947, US army military government in Korea strongly oppressed the left performances to stop and theatrical movement was ended due to many left theatrical people defection to North Korea. The political theatre in 1960s to 70s the Park regime, developed in dramatically different ways according to orthodox group and group out of power. The political theatre of institutional system handled judgment on sterile people and had indirect political theatre from that took history material and allegory technique because of censorship. In political theatre out of institution, it started outdoor theatre that has modernized traditional performance style and established deep relationship with labor spot and culture movement organizations. Madangguek(Outdoor theatre) is 'Attentive political theatre', satirizing and offending the political and social inconsistencies such as the dictatorial government's oppression and unbalanced distribution, alienation of general people, and foreign powers' pillage sharply as well as laughing at the Establishment with negative characters. The political theatre in 1980s is divided into two categories; political theatre of institutional system and Madangguek. Institutional Political theatre mainly performed in Korea Theatre Festival and the theatre group 'Yeonwoo-Moudae' led political theatre as private theatre company. Madangguek developed into an outdoor theatrical for indoor theatre capturing postcolonial historical view. Yeonwoo-Moudae theatre company produced representative political plays at 80s such as The chronicles of Han's, Birds fly away too, and so on by combining freewheeling play spirit of Madangguek and epic theatre. Political theatre was all the rage since the age of democratization started in 1987 and political materials has been freed from ban. However, political theatre was slowly declined as real socialism was crumbling and postmodernism is becoming the spirit of the times. After 90s, there are no more plays of ideology and propaganda that aim at politicization of theatre. As the age rapidly entered into the age of deideology, political theatre discourse also changed greatly. The concept 'the political' became influential as a new political possibility that stands up to neoliberalism system in the evasion of politics. Rather than reenact political issues, it experiments new political theatre that involves something political by deconstructing and reassigning audience's political sense with provocative forms, staging others and drawing discussion about it.

Separation Characteristic and Recycling of Excavated Materials Containing Waste (폐기물혼입굴착물의 선별특성과 재활용성 평가)

  • Lee, Suyoung;Kim, Kyuyeon;Jeon, Taewan;Shin, Sunkyoung
    • Journal of the Korea Organic Resources Recycling Association
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    • v.27 no.2
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    • pp.5-12
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    • 2019
  • The study is carried out to survey the proper management and to propose an eco - friendly separation system through efficient screening and resource recovery of excavated materials containing waste from various excavating fields such as reconstruction of landfill sites for reuse, reclamation of unsanitary landfill and residential land development of waste dumping sites. The current status and screening process and analytical characteristics of the excavated materials containing waste were reviewed. Through the analysis of the samples such as separated combustibles, recyclable soils and residues collected from the on-site visits we were able to understand the characteristics of separated materials and excavated materials containing waste such as calorific value, elementary composition, TOC, foreign material content and LOI. It has been found that elimination of the moisture of excavations, removal of attached soil from the surfaces of the excavated combustibles and the quantitative supply method of the input devices are the main operating factors as essential factors for the optimal separation of excavated materials containing waste. For efficient management and recycling of excavated materials containing, it is necessary to set criteria of ash content in separated combustibles and criteria organic matter content in separated soils.

Analyzing Characteristic of Deterioration Status for Stone Properties in the Tae-Jo Geonwolleung of the Royal Tombs of the Joseon Dynasty (조선왕릉 태조 건원릉 내 석물의 훼손 특성 분석)

  • Lee, Mi Hye;Lee, Myeong Seong;Chun, Yu Gun;Lee, Tae Jong
    • Korean Journal of Heritage: History & Science
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    • v.48 no.4
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    • pp.62-73
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    • 2015
  • The Tae-Jo Geonwolleung is the tomb of the first king Tae-Jo of the Joseon Dynasty in the complex of the Royal Tombs of the Joseon Dynasty which is listed in World Heritage, and it contains various types of stone properties. The material of the stone properties consist of a single type of medium-grained biotite granite, however, each properties have different intensity and types in deterioration phenomena according to their locations and purposes. The major deterioration types of the stones are analyzed as physical decomposition and biodeterioration. The exfoliation, breaking-out and granular decomposition are widespread types of the deterioration throughout the entire burial mound stone properties and surrounding stone properties. On the other hands, the colonization of mosses and plants, and contamination by foreign materials are found more frequent in the burial mound stone properties as these stones are in contact with the soil of the tomb mound and moisture in the soil helped biodeterioration. It is suggested that anti-biology treatment and physical reinforcement are applied to the deteriorated stones to prevent further damage on the stone components of the tomb.