• Title/Summary/Keyword: 해양사

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Effects of Water Temperature and Photoperiod on the Oxygen Consumption Rate of Fasted Juvenile Parrot Fish, Oplegnathus fasciatus (돌돔, Oplegnathus fasciatus 치어의 절식시 산소 소비율에 미치는 수온과 광주기의 영향)

  • Oh, Sung-Yong;Noh, Choong-Hwan;Kang, Rae-Seon;Myoung, Jung-Goo
    • Ocean and Polar Research
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    • v.28 no.4
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    • pp.407-413
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    • 2006
  • The effect of water temperature and photoperiod on the oxygen consumption of the fasted juvenile parrot fish, Oplegnathus fasciatus was investigated to provide empirical data for the early-stage culture management and bioenergetic growth model of the species. The mean body weight of the juvenile used for the experiment was $21.5{\pm}1.9g$, and the oxygen consumption rate was measured under four water temperatures (10, 15, 20 and $25^{\circ}C$) and three photoperiods (24L:0D, 12L:12D and OL:24D) with an interval of 5 minutes for 24 hours using a continuous flow-through respirometer. In each treatment three replicates were set up and 15 juveniles were totally involved. The oxygen consumption rates increased with increasing water temperature under all photoperiod treatments (P<0.001). Mean oxygen consumption rates at 10, 15, 20 and $25^{\circ}C$ ranged $202.1{\sim}403.4,\;306.7{\sim}502.2,\;536.7{\sim}791.0\;and\;879.9{\sim}1,077.4mg\;O_2\;kg^{-1}h^{-1}$, respectively. $Q_{10}$ values ranged $1.58{\sim}2.30$ between 10 and $15^{\circ}C,\;2.44{\sim}3.06$ between 15 and $20^{\circ}C\;and\;1.86{\sim}2.6y9$ between 20 and $25^{\circ}C$, respectively. Mean oxygen consumption rates of O. fasciatus were the highest in continuous light (24L:0D) followed by 12L:12D and 0L:24D (P<0.001). The oxygen consumption of fish exposed to the 12L:12D photoperiod was significantly higher during the light phase than during the dark phase under all temperature treatments (P<0.001). In summary, oxygen consumption rates of the juvenile parrot fish increase with increasing water temperature and lengthening daylight period; and, thereby, changes in water quality resulted from the depletion of oxygen under high temperature and long daylight photoperiod conditions should be monitored.

Macrobenthic Faunal Assemblages on the Soft-Bottoms around Dokdo in the East Sea, Korea (한국 동해 독도 주변 천해 및 사면해역의 대형저서동물군집)

  • Choi, Jin-Woo;Hyun, Sang-Min;Kim, Dong-Sung;Kim, Woong-Seo
    • Ocean and Polar Research
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    • v.24 no.4
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    • pp.429-442
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    • 2002
  • The faunal assembalges of macrobenthos and their habitat conditions on the soft-bottoms around Dokdo(Dok Island) was investigated using a box corer and a van Veen grab in Sept. 1999 and May 2000. The sediments in the slope sites were composed of sand particles and those in Ullneung Basin were mud. The sediments in the shelf sites were in the range of fine to medium sand. The organic content of the slope sediments was in the range of 1 to 2%. The macrobenthos occurred at the slope sites represented by 15faunal groups belonging to 8 phyla, and the major faunal group was polychaetous annelids. They comprised ca. 80.6% in slope sites, and 84.8% in shelf sites. Dominant species in the slope were Exogone verugera(40.9%), Cossura longocirrata (8.4%), Tharyx sp. (6.6%), Scalibregma inflatum (4.9%), Aedicira sp. (4.7%), Aricidea ramosa (3.8%), and Sigambra tentaculata (3.7%). Dominant species in the shelf were Chone sp. (49.3%), Tharyx sp. (18.4%), Ophelina acuminata (6.7%), Chaetozone setosa (3.8%), Glycera sp. (2.6%), and Aedicira sp. (2.4%). The mean densities of macrobenthos in the slope and shelf area were $2,028\;ind./m^2$ and $456\;ind./m^2$, respectively. The trophic composition of benthic polychaete worms in the slope area was different from that in shallow shelf area: surface deposit feeding worms were most abundant in slope area whereas filter feeding worms in shelf area. According to the cluster analysis and MDS plots, the spatial distribution of macrobenthos in Dokdo slope region was related with the sediment properties such as particle size and organic content. In the case of vertical distribution of macrobenthos in slope sites, most faunas concentrated in the upper sediment layer within 2cm depth.

The Legal Response and Future Tasks regarding Oil-Spill Damage to Korea - Focusing on the Hebei Spirit oil-spill (한국의 해양유류오염피해에 대한 법적 대응과 과제 - HEBEI SPIRIT호 유류유출사고를 중심으로 -)

  • Han, Sang-Woon
    • Journal of Environmental Policy
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    • v.7 no.3
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    • pp.89-120
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    • 2008
  • With petroleum being a major source of energy in Korea, the quantity of petroleum transported via ocean routes is on its way up due to increased consumption. Due to the increase, more than 300 cases of pollution caused by petroleum occur annually. Moreover, the number of oil-spill accidents is also on the rise. Causes of such accidents, not including the disposal of waste oil on purpose, turn out to be human error during navigation or defects in the vessels, showing that most accidents are caused by humans. Therefore, to prevent future oil spills, it is imperative that navigation efficiency be enhanced by improving the quality of navigators and replacing old vessels with newer ones. Nevertheless, such improvements cannot occur overnight, so long- and mid-term efforts should be made to achieve it institutionally. As large-scale oil-spill accidents can happen at anytime along the coastal waters of Korea, it is necessary to set-up institutional devices which go beyond the compensation limit of 92FC. The current special law regarding this issue has its limits in that it prescribes compensation be supplemented solely by national taxes. Therefore, the setting-up of a new 'national fund' is recommended for consideration rather than to subscribe to the '2003 Convention for the Supplementary Fund'. It is strongly suggested that a National fund be created from fees collected from oil companies based on the risks involved in oil transportation and according to the profiteers pay principle. In addition, a public fund should be created to handle general environmental damage, such as the large-scale destruction of the ecosystem, which is distinct from the economic damage that harms the local people. The posterior responses to the large-scale oil spill have always been unsatisfactory because of the symbolic nature of the disasters included in such accidents. Oil-spills can be prevented in advance, because they are caused by human beings. But once they occur, they inflict long-term damage to both human life and the natural ecosystem. Therefore, the best response to future oil-spills is to work to prevent them.

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Supercargo and Temporary Passengers (화물관리인과 임시승선자)

  • Choi, Suk-Yoon;Hong, Sung-Hwa;Ha, Chang-Woo
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2018.11a
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    • pp.225-227
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    • 2018
  • This research paper examines the history and present of 'temporary passengers' prescribed in Paragraph 9 of Article 5 of the Ships Safety Act Enforcement Regulations and suggests improvement plans referring to the examples of legislation of other countries. In 2015, Ministry of Ocean and Fisheries made authoritative interpretation that Paragraph 9 of Article 5 of the Ships Safety Act Enforcement Regulations, which prescribes special cargo drivers such as agricultural, marine or livestock vehicles as temporary passengers, is applied only to passenger ships and not to cargo ships such including Ro-Ro cargo ships. As the authoritative interpretation of the Ministry does not agree with not only the traditional interpretational methodology but also the interpretational methodology that are commonly used today, it lacks logical basis and looks unpersuasive. Paragraph 9 of Article 5 of the Ships Safety Act Enforcement Regulations can be applied not only on passenger ships but also on cargo ships. Also in case of Ro-Ro cargo ships, it is logically contradictory and against fairness not to acknowledge special cargo vehicle drivers as temporary passengers when there is no problem with safe navigation and safety of passengers on board even when the sailor, the sailor's family and the ship owner may be acknowledged as temporary passengers. To avoid unnecessary disputes and lawsuits, improvement plans using theory of legislation through statutory reform is more desirable. Therefore, the P aragraph should be amended to "Supercargo who deals with cargo that requires special care due to the characteristics of the cargo, such as transportation vehicles for agricultural products, marine products, livestock, explosives or flammable materials (drivers can serve as supercargos)" to reflect the distinct characteristics of cargo and ship navigation in Korea including the current distribution system, while setting an objective standard based on common sense of ordinary people and not on arbitrary interpretation.

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A Study on Inventory and Grade Evaluation of the Visual Landscape Resource in Mt. Chiak National Park (치악산국립공원의 시각적 경관자원 인벤토리 구축 및 등급평가에 관한 연구)

  • Lee, Sook-Hyang
    • Journal of the Korean Institute of Landscape Architecture
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    • v.44 no.4
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    • pp.57-65
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    • 2016
  • This study was conducted a visual landscape resources inventory and grade assessment on natural resources and cultural resources of Chiaksan National Park. Landscapes of National Parks are categorized into four types: seascape, mountain landscape, village landscape, and temple historical landscape. Landscape lists were constructed for each district for a total of 120 lists through field research on 7 trails. The landscape list per trail has Guryong~Birobong(31%), Seungnam~Namdaebong(22%), Geumdae~Namdaebong(16%), Bugok~Hanenggu(165), Hwanggol~Ipseoksa(6%), Hyangrobong~Nandaebong(5%) and Godeunjae~Wontonggol(4%). Landscape Assessment items were divided into five characteristics of view, unique, use, history culture, natural reflected by item. Items were divided into three grades of landscape by 4, 3, 2, 1 for each item of the assessment criteria and Delphi survey. Mountain landscapes were assessed in I grade of 72 sites, II grade of 26 sites, III grade of 7 sites. Temple Historical landscapes were assessed in I grade of 4 sites, II grade of 7 sites, III grade of 4 sites. The study results can be used as a basis for mountain parks management. It is necessary to focus on managing the landscape of I grade site. The higher ratings of the Mountain landscapes are related to the view and natural score. Also, the grading of Temple Historical landscapes is related to the history cultural, natural and use score. In addition, the mountain landscape were identified as being included outside landscape resources, the place of landscape resources with outside ratings were higher and the view was related. Landscape management is needed for the conservation of Mountain landscape and Temple Historical landscape type rating as excellent areas on the basis of the results of the inventory and assessment. For future improvement the Guryong-Birobong trail is judged as a harmonious representative landscape of the Mountain and Temple Historical landscape and will require conservation as a focus management area. In the case of Mountain landscape improvements, maintenance such as pruning trees, wood observatory and interpretation sign for a landscape with minimal inhibitory landscaping is needed. When installing artificial facilities in the Temple Historical landscapes, the use of materials harmonizing with the surroundings landscape must be considered as well as the standards of facilities limitation.

The Northeast Asian Rim:A geopolitical perspective (지정학적 관점에서 본 동북아권)

  • Yu, Woo-ik
    • Journal of the Korean Geographical Society
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    • v.28 no.4
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    • pp.312-320
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    • 1993
  • Along with the fade out of the Cold War the world is undergoing a fundamental restructuring. The process is generally refered to regionalization and globalization. In this context, the Paper presents a geopolitical perspective on the future of Northeast Asia. To meet the global trend, it is expected that the countries in the area organize an economically cooperative unity, the concept of which the author calls the northeast Asian Rim (NEAR). With its huge potentials to become the largest economic area in the world and with its rather complicated historical and social background, the Rim is tentatively supposed to have a loose and soft organization, to be flexible in dealing with the intra-and interregional relations. The idea underlying the view is that the former area of confrontation between the land power and the sea power is, under the new world environment, going to recover its proper locational attributes and develop into a merging area, a new core. As a physical framework of the Rim a spatial structurc is assumed to consist of two-subrims and two development axes with four development centers.

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A Study on the Construction method of Stamped earthen wall (판축토성(版築土城) 축조기법(築造技法)의 이해(理解) - 풍납토성(風納土城) 축조기술(築造技術)을 중심(中心)으로 -)

  • Shin, Hee-kweon
    • Korean Journal of Heritage: History & Science
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    • v.47 no.1
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    • pp.102-115
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    • 2014
  • The stamped earth method is a typical ancient engineering technique which consists of in-filling wooden frame with layers of stamped earth or sand. This method has been universally used to construct earthen walls and buildings, etc. The purpose of this article is to understand the construction method and principles of the stamped earthen wall through analysis of various construction techniques of Pungnaptoseong Fortress(Earthen Fortification in Pungnap-dong). First of all, the ground was leveled and the foundations for the construction of the earthen wall were laid. The underground foundation of the earthen walls was usually constructed by digging into the ground and then in-filling this space with layers of mud clay. Occasionally wooden posts or paving stones which may have been used to reinforce the soft ground were driven in. The method of adding layers of stamped earth at an oblique angle to either side of a central wall is the most characteristic feature of Pungnaptoseong Fortress. Even though the traces of fixing posts, boards, and the hardening of earth - all signatures of the stamped earth technique - have not been identified, evidence of a wooden frame has been found. It has also been observed that this section was constructed by including layers of mud clay and organic remains such as leaves and twigs in order to strengthen the adhesiveness of the structures. The outer part of the central wall was constructed by the anti-slope stamped earth technique to protect central wall. In addition a final layer of paved stones was added to the upper part of the wall. These stone layers and the stone wall were constructed in order to prevent the loss of the earthen wall and to discharge and drain water. Meanwhile, the technique of cementing with fire was used to control damp and remove water in stamped earth. It can not be said at present that the stamped earth method has been confirmed as the typical construction method of Korean ancient earthen walls. If we make a comparative study of the evidence of the stamped earth technique at Pungnaptoseong Fortress with other archeological sites, progress will be made in the investigation of the construction method and principles of stamped earthen wall.

Changing Aspects and Factors of Shaman's Play in Donghaeanbyeolsingut (동해안별신굿 굿놀이의 변화양상과 요인)

  • Kim, Shin-Hyo
    • (The) Research of the performance art and culture
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    • no.38
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    • pp.33-69
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    • 2019
  • In this article, I would like to pay attention to the changesofShaman's play as a part of examining the process of changeofDonghaeanbyeolsingut. Currently, Shaman's play can be seeninBaekseok2-ri, Byeonggok-myeon, Yeongdeok-gun, Gugye-ri, Namjeong-myeon and Yeongdeok-gun. Among them, ShamanRitual of Baekseok2-ri is short in cycle and easy to see change. InShaman Ritual of Baekseok2-ri, various Shaman's plays suchasJungdodukjabi(중도둑잡이), Wonnimnori(원님놀이), Talgut(탈굿), Mallori(말놀이), Hotalgut(호탈굿) and Georigut(거리굿) areperformed. Shaman's play carried out in Donghaeanbyeolsingut changesevery time it is carried out. Depending on the degree of change, itcan be classified into passive change and positive change. Whilepassive changes are improvisational, aggressive changes areintentional. Shaman's plays are jungdodukjabi, Mallori, Hotalgut, which are the improvisational changes, and the intentional changesare Wonnimnori, Talgut, Georigut. The biggest change in Shaman's play is the disappearance of the Shaman Ritual. The Shaman Ritual is suspended due to lackofpeople, financial difficulties, religious conflicts or rational accidents. Secondly, the period of separation is shortened or shortened. Thiscauses Shaman's play to be dropped or shrunk to change. InShaman Ritual, changes in Shaman's play are variable andcreative. The change due to the intervention of the spectatorsismainly improvisation. On the other hand, the change bythepreliminary plan of the acquaintance is intentional, and the changeis large. The changing factors of Shaman's play are influenced bythedemands of the times and the recognition of the tradition group. Changes in the traditional environment can be attributed to lackofhuman resources, individualism, changes in the workingenvironment and time constraints. At the same time, givingautonomy to traffickers is a major reason for Shaman's playtochange.

Cultural Practices for Reducing Cold Wind Damage of Rice Plant in Eastern Coastal Area of Korea (동해안지대 도작의 냉조풍피해와 피해경감대책)

  • 이승필;김칠용
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.36 no.5
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    • pp.407-428
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    • 1991
  • The eastern coastal area having variability of climate is located within Taebaek mountain range and the east coast of Korea. It is therefore ease to cause the wind damages in paddy field during rice growing season. The wind damages to rice plant in this area were mainly caused by the Fohn wind (dry and hot wind) blowing over the Taebaek mountain range and the cold humid wind from the coast. The dry wind cause such as the white head, broken leaves, cut-leaves, dried leaves, shattering of grain, glume discolouration and lodging, On the other hand the cold humid wind derived from Ootsuku air mass in summer cause such symptom as the poor rice growth, degeneration of rachis brenches and poor ripening. To minimize the wind damages and utilize as a preparatory data for wind injury of rice in future, several experiments such as the selection of wind resistant variety to wind damage, determination of optimum transplanting date, improvement of fertilizer application methods, improvement of soils and effect of wind break net were carried out for 8 years from 1982 to 1989 in the eastern coastal area. The results obtained are summarized as follows. 1. According to available statisical data from Korean meteorological services (1954-1989) it is apperent that cold humid winds frequently cause damage to rice fields from August 10th to September 10th, it is therefore advisable to plan rice cultivation in such a way that the heading date should not be later than August 10th. 2. During the rice production season, two winds cause severe damage to the rice fields in eastern coastal area of Korea. One is the Fohn winds blowing over the Taebaek mountain range and the other is the cold humid wind form the coast. The frequency of occurrence of each wind was 25%. 3. To avoid damage caused by typhoon winds three different varieties of rice were planted at various areas. 4. In the eastern coastal area of Korea, the optimum ripening temperature for rice was about 22.2$^{\circ}C$ and the optimum heading date wad August 10th. The optimum transplanting time for the earily maturity variety was June 10th., medium maturity variety was May 20th and that of late maturity was May 10th by means of growing days degree (GDD) from transplanting date to heading date. 5.38% of this coastal area is sandy loamy soil while 28% is high humus soil. These soil types are very poor for rice cultivation. In this coastal area, the water table is high, the drainage is poor and the water temperature is low. The low water temperature makes it difficult for urea to dissolve, as a result rice growth was delayed, and the rice plant became sterile. But over application of urea resulted in blast disease in rice plants. It is therefore advise that Ammonium sulphate is used in this area instead of urea. 6. The low temperature of the soil inhibits activities of microorganism for phosphorus utilization so the rice plant could not easily absorb the phosphorus in the soil. Therefore phosphorus should be applied in splits from transplanting to panicle initiation rather than based application. 7. Wind damage was severe in the sandy loamy soil as compared to clay soils. With the application of silicate. compost and soil from mointain area. the sand loamy soil was improved for rice grain colour and ripening. 8. The use of wind break nets created a mocro-climate such as increased air. soil and water temperature as well as the reduction of wind velocity by 30%. This hastened rice growth, reduced white head and glume discolouration. improved rice quality and increased yield. 9. Two meter high wind break net was used around the rice experimental fields and the top of it. The material was polyethylene sheets. The optimum spacing was 0.5Cm x 0.5Cm. and that of setting up the wind break net was before panicle initiation. With this set up, the field was avoided off th cold humid wind and the Fohn. The yield in the treatment was 20% higher than the control. 10. After typhoon, paddy field was irrigated deeply and water was sprayed to reduce white head, glume discolouration, so rice yield was increased because of increasing ripening ratio and 1, 000 grain weight.

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