• Title/Summary/Keyword: Waterway cover

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An Experimental Study for Drainage Capacity Improvement of Waterway with Steep Slope (급경사 사면 도수로의 배수능력 개선을 위한 실험적 연구)

  • Kim, Jung Soo;Kim, Ju Hyung;Yoon, Sei Eui
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.33 no.6
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    • pp.2303-2315
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    • 2013
  • In general, the waterway was installed for drain water from steep slope and waterway cover was set up to prevent overflow and water separation at berm of waterway. In this study, hydraulic experiment was conducted to analyze the flow characteristics and enact standard design criteria of the waterway. Hydraulic experimental apparatus which can change the slope of waterway and the length of berm were installed to analyze of flow characteristics at the waterway. The slopes of waterway were $40^{\circ}$, $50^{\circ}$, $60^{\circ}$, and $70^{\circ}$ and the range of discharge were 1.0~5.6 ${\ell}/s$. The flow in berm was distinguished two types such as hydraulic jump and splash flow. These kinds of flows depended on the rates of discharge in waterway. When inlet discharge was below 1.1~2.0 ${\ell}/s$, the separation phenomenon of water was generated at upper and lower portion in berm by the splash flow. The scattering range of water particles and length of water separation was measured depending on the slope of waterway. The start point of scattering was about 20 cm(1.3B) from the place connected upper waterway with brem and the length of water separation was till 210 cm(3.5B) from the place connected lower waterway with brem. Therefore, the waterway cover needed to install from starting of berm to 1B and from the lower part of berm to 3.5B.

Management Strategies to Conserve Soil and Water Qualities in the Sloping Uplands in Korea (한국의 경사지 밭의 토양 및 물의 보전 관리 전략)

  • Yang, Jae-E.;Ryu, Jin-Hee;Kim, Si-Joo;Chung, Doug-Young
    • Korean Journal of Agricultural Science
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    • v.37 no.3
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    • pp.435-449
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    • 2010
  • Soils in the sloping uplands in Korea are subject to intensive land use with high input of agrochemicals and are vulnerable to soil erosion. Development of the environmentally sound land management strategy is essential for a sustainable production system in the sloping upland. This report addresses the status of upland agriculture and the best management practices for the uplands toward the sustainable agriculture. More than 60% of Korean lands are forest and only 21% are cultivating paddy and upland. Uplands are about 7% of the total lands and about 62% of the uplands are in the slopes higher than 7%. Due to the site-specificity of the upland, many managerial and environmental problems are occurring, such as severe erosion, shallow surface soils with rocky fragments, and loadings of non-point source (NPS) contaminants into the watershed. Based on the field trials, most of the sloping uplands were classified as Suitability Class III-V and the major limiting factor was slope and rock fragments. Due to this, soils were over-applied with N fertilizer, even though N rate was the recommendation. This resulted in decreases in yield, degradation of soil quality and increases in N loading to the leachate. Various case studies drew management practices toward sustainable production systems. The suggested BMP on the managerial, vegetative, and structural options were to practice buffer strips along the edges of fields and streams, winter cover crop, contour and mulching farming, detention weir, diversion drains, grassed waterway, and slope arrangement. With these options, conservation effects such as reductions in raindrop impact, flow velocity, runoff and sediment loss, and rill and gully erosion were observed. The proper management practice is a key element of the conservation of the soil and water in the sloping upland.

A Waste Load Allocation Study for Water Quality Management of the Incheon Coastal Environment (인천해안의 수질관리를 위한 오염부하량 할당에 관한 연구)

  • Kim, So-Yeon;Choi, Jung-Hyun;Na, Eun-Hye;Park, Seok-Soon
    • Journal of Korean Society of Environmental Engineers
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    • v.27 no.1
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    • pp.43-51
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    • 2005
  • This paper presents a waste load allocation study for the Incheon coastal environment, where a computer model, called AQUASEA, was applied. A finite element mesh was constructed and refined to cover the complicated geometry of Incheon coastal sea. The tidal height at 13 places of Incheon coastal boundary and flow of the Han River were given as an input condition to the tidal simulation. All pollution sources that discharge into Incheon coast were given as input data to the water quality simulation. The modeled parameters include tidal flow and COD(Chemical Oxygen Demand). The model was calibrated and verified with the field measurements. The model results showed reasonable agreements with field measurements in both tidal flow and water quality. Systems analysis showed that the pollution load from the Han River caused recognizable impacts on the water quality of Incheon coast from Yeomhwa waterway to northern area of Younghungdo. The loads from Incheon City affected water quality from the area below Youngjongdo to the area above Jawalldo. The discharge from the Sihwa Lake caused discernible impacts on the coastal zone from the dike outlet to the Incheon harbor, and pollution loads from Kyungkido affected the sea near the Oido. An effective water quality management plan was developed from the waste load allocation analysis of the validated model, that the maximum waste loads can be discharged without violating the water quality standard given in the Incheon coastal environment.

A Review on the Interpretative Guidelines on EU Air Transport Passenger Rights Regulations in the Context of the Developing Situation with COVID-19 (항공여객보상에 관한 EC 261/2004 규칙의 COVID-19 관련 해석지침 검토)

  • Sur, Ji-Min
    • The Korean Journal of Air & Space Law and Policy
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    • v.35 no.3
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    • pp.39-63
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    • 2020
  • This paper reviews the Interpretative Guidelines on EU passenger rights regulations in the context of the developing situation with COVID-19 of EU commission. To enlighten the obscurity and to mitigate the economic impacts of the COVID-19, European Commission has published "Interpretative Guidelines on EU passenger rights regulations in the context of the developing situation with Covid-19" on March 18, 2020. The Guideline essentially aims to create a coherent system of rules to assist the passengers, industry and national authorities overall under the unprecedented circumstances across the European Union. To do so, the Guideline is drafted to cover the rights of passengers travelling by air, rail, ship or bus/coach, maritime and inland waterways, as well as the corresponding obligations for carriers. From an aviation industry focused perspective, by referencing the Regulation (EC) numbered 261/2004, the Guideline specifically applies to cancellation and delay in flights which are seen as the dark spots for the air carriers concerning potential burdens.

Problems on the Door to Door Application of International Air Law Conventions (국제항공운송협약의 Door to Door 운송에의 적용에 관한 문제점)

  • CHOI, Myung-Kook
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.78
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    • pp.1-29
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    • 2018
  • This article demonstrates that both the Warsaw Convention Systemand the Montreal Convention are not designed for multimodal transport, let alone for "Door to Door" transport. The polemic directed against the "Door to Door" application of the Warsaw Convention systemand the Montreal Convention is predominantly driven by the text and the drafting philosophy of the said Contentions that since 1929 support unimodalism-with the rule that "the period of the carriage by air does not expend to any carriage by land, by sea or by inland waterway performed outside an airport" playing a profound role in restricting their multimodal aspirations. The drafters of the Montreal Convention were more adventurous than their predecessors with respect to the boundaries of the Montreal Convention. They amended Art. 18(3) by removing the phrase "whether in an aerodrome or on board an aircraft, or, in the case of landing outside an aerodrome, in any place whatsoever", however, they retained the first sentence of Art. 18(4). The deletion of the airport limitation fromArt. 18(3) creates its own paradox. The carrier can be held liable under the Montreal Convention for the loss or damage to cargo while it is in its charge in a warehouse outside an airport. Yet, damage or loss of the same cargo that occurs during its surface transportation to the aforementioned warehouse and vice versa is not covered by the Montreal Convention fromthe moment the cargo crosses the airport's perimeter. Surely, this result could not have been the intention of its drafters: it certainly does not make any commercial sense. I think that a better solution to the paradox is to apply the "functional interpretation" of the term"airport". This would retain the integrity of the text of the Montreal Convention, make sense of the change in the wording of Art. 18(3), and nevertheless retain the Convention's unimodal philosophy. English courts so far remain loyal to the judgment of the Court of Appeal in Quantum, which constitutes bad news for the supporters of the multimodal scope of the Montreal Convention. According the US cases, any losses occurring during Door to Door transportation under an air waybill which involves a dominant air segment are subject to the international air law conventions. Any domestic rules that might be applicable to the road segment are blatantly overlooked. Undoubtedly, the approach of the US makes commercial. But this policy decision by arguing that the intention of the drafters of the Warsaw Convention was to cover Door to Door transportation is mistaken. Any expansion to multimodal transport would require an amendment to the Montreal Convention, Arts 18 and 38, one that is not in the plans for the foreseeable future. Yet there is no doubt that air carriers and freight forwarders will continue to push hard for such expansion, especially in the USA, where courts are more accommodating.

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