• Journal of Korea Water Resources Association
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• v.45 no.1
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• pp.39-52
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• 2012

Surface-subsurface interactions are an intrinsic component of the hydrologic response within a watershed. In general, these interactions are considered to be one of the most difficult areas of the discipline, particularly for the modeler who intends simulate the dynamic relations between these two major domains of the hydrological cycle. In essence, one major complexity is the spatial and temporal variations in the dynamically interacting system behavior. The proper simulation of these variations requires the need for providing an appropriate coupling mechanism between the surface and subsurface components of the system. In this study, an approach for modelling surface-subsurface flow and transport in a fully intergrated way is presented. The model uses the 2-dimensional diffusion wave equation for sheet surface water flow, and the Boussinesq equation with the Darcy's law and Dupuit-Forchheimer's assumption for variably saturated subsurface water flow. The coupled system of equations governing surface and subsurface flows is discretized using the finite volume method with central differencing in space and the Crank-Nicolson method in time. The interactions between surface and subsurface flows are considered mass balance based on the continuity conditions of pressure head and exchange flux. The major module consists of four sub-module (SUBFA, SFA, IA and NS module) is developed.

• Journal of the Korean association of regional geographers
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• v.22 no.4
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• pp.887-911
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• 2016

The empirical law that transverse dunes migrate inversely with their heights leads logically to the prediction that multiple dune ridges will converse to a single huge dune by merging. This contradicts the existence of the steady state dune fields on the Earth. The recent studies have emphasized dune collisions as a key mechanism to the stability of dunefield. The roles of wind shadow aspect ratio, however, have yet to be fully explored. This research aims to investigate the potential roles of wind shadow aspect ratio in the dynamical behaviors of transverse dune field. The simplified model is established for this, based upon allometric properties of transverse dunes, wind speedup on the stoss slope and sand trapping efficiency. The derived governing equations can be transformed to the zoning criteria and vector field for dune evolution. The dynamics analysis indicates that wind shadow aspect ratios do not produce convergent areas on the behavior space; rather, they just act as one of the factors that affect the trajectories of dune evolution. Though the model cannot represent the stability of dune field, but seem to produce a reasonable exponent for dune spacing-height relations.

• Journal of Fisheries and Marine Sciences Education
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• v.26 no.6
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• pp.1278-1295
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• 2014

The Sixteenth Meeting of the Conferences of Parties of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), which was held in March 2013 in Bangkok, Thailand, listed five shark species and one genus, and uplisted one sawfish species. All new species listings will be come into force of the eighteen months delay, on the fourteenth of September, 2014. The purpose of the delay is to support the preparation of the domestic measures on shark trade by the parties, as there has been no previous experience in trading the commercially exploited aquatic species in the CITES. The CITES Secretary-General has visited several potential shark trade countries to encourage and facilitate the implementation of the new CITES listings. The newly listed sharks have been caught as a target or non-target species by Korean distant water fisheries and introduced into Korea. So the establishment or change of the domestic laws, regulations, and measures for the implementation of the new CITES species must be prepared before the effective entry date. This paper is prepared to assess the effects of the trade of the CITES listed shark species, and to suggest effective government service measures for the management of Korean distant water fisheries. The Ministry of Environment (MOE) is the general Management Authority of the CITES, and the Ministry of Food and Drug Safety (MFDS) is in charge of the medical trade of CITES listed species in Korea. By law, all imported medicines and medical materials must be inspected by the MFDS during the customs examination; this kind of authority sharing is reasonable and effective way of providing government service. Similarly, the designation of new CITES Management Authority for the trade of commercially exploited aquatic CITES species is critical and the Ministry of Oceans and Fisheries (MOF), which is now in charge of the trade of fisheries products, is the most appropriate governing body for this purpose in Korea. The revision of the National Plan of Action for Conservation and Management of Sharks, initially submitted to the Food and Agriculture Organization (FAO) of the United Nations in 2011 as a practical guideline for shark conservation in all Korean fisheries, could be a effective measure to achieve unification of conservation of endangered species and sustainable use of fisheries stocks. The proper CITES measures for the trade of listed species, such as the establishment of the documenting system for Non-detriment Findings, domestic measures suitable for the "Introduction from the Sea" clause, species specific Harmonized System Codes for the customs service, and an effective shark catch data reporting system should be in place prior to the fourteenth of September 2014.

• Journal of Korea Trade
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• v.24 no.4
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• pp.49-70
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• 2020

Purpose - The UCP is recognized as the governing law for L/C transactions, but it covers only the general details of the transaction and does not cover all complex practices. In view of this limitation, this paper examines a negotiation transaction which is most actively utilized in L/C transactions via a thorough review of the UCP provisions, analyzes the problems of the negotiation clause in the UCP, and suggests appropriate countermeasures to deal with unnecessary litigation costs. By doing so, the parties involved in the negotiation transaction would be able to avoid financial costs such as having to pay for lawsuits. Design/methodology - The present study first differentiates the general types of L/Cs (e.g., sight payment L/C, deferred payment L/C, acceptance L/C, and negotiation L/C), explains and the Article 2 and Article 12(b) of the UCP 600 where the term 'negotiation' is used, digs into the drawbacks of 'negotiation' occurring under the UCP 600, and discusses solutions to the problems found by analyzing the drawbacks descriptively. Findings - After a review of the UCP provisions on negotiation in detail, several possible problems which may occur in practice were discovered. First, as the UCP stipulates, the negotiating bank will want to delay payment to the maximum extent possible and make payment on the banking day on which the issuing bank reimburses the amount. This may lead the beneficiary towards bankruptcy or put it in financial crisis. Second, when a fraudulent transaction occurs, the negotiating bank can neither request the issuing bank to reimburse nor can it exercise its recourse right against the beneficiary because it has obtained all the rights of the beneficiary by purchasing the documents. Third, there is a practice in which the beneficiary sells the documents to its transaction bank which is not the nominated bank if the nominated bank specified in the credit is located in a third country or the exporter has no relationship with the nominated bank in the credit. In this case, whether to accept this and reimburse the non-nominated negotiating bank entirely depends on the issuing bank's decision even though such practice frequently occurs in Korea. Originality/value - There has been little research effort pertaining to negotiation transactions in detail even though negotiation L/C transactions account for around 70% in world trade notwithstanding deferred payment L/Cs and acceptance L/Cs that are also negotiated in practice. Thus, if the negotiations clause under the UCP 600 provisions were reviewed and the drawbacks of the negotiation transactions most actively used in L/C transactions were identified and examined, specific countermeasures could ultimately help smoothen the operation of L/C transactions and prevent financial losses.

• Korea Trade Review
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• v.42 no.1
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• pp.257-281
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• 2017

It becomes a common feature of business practices in International Trade to use a standard terms for the formation of their contracts. However, because of differences in legal systems, business practices and so on in their own countries, there have been many conflicts and disputes happening between parties concerned in International Trade. The CISG, which has long been used as the governing law in many cases of International Trade, could not be free from those conflicting issues in its usage and application. This study analyzes the "Black Letter Rules" which was adopted by CISG Advisory Council in 2013 to provide an effective way of resolving the conflicting issues regarding the inclusion of standard terms in International Trade Contracts under the CISG. This study scrutinizes, the relevant rules and requirements for the inclusion of standard terms into a contract. It also deals with the offeror's duty of making clear reference to the standard terms, transmitting the contents of standard terms to the other party. As the other rules for the inclusion of standard terms, this study reviews the principle of denying the inclusion of standard terms after the formation of contracts, exclusion of surprising or unusual terms, preference of individually negotiated terms to the standard terms, contra preferentum rule and preference of the "knock-out rule" to "last-shot rule" in resolving the issue of so called, "Battle of Forms." Lastly, on the basis of analyzed opinion, this study suggests the practical implications for the people working at International Trade-related business sector to facilitate International Trade.

• Korea Trade Review
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• v.42 no.2
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• pp.205-225
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• 2017

The study attempts to verify the case related to the notice of payment refusal by issuing bank regarding discrepancy in transport document under L/C(Letter of Credit) transaction. Considering the high portion of trade between Korea and China, Korean companies and banks in L/C transaction should be careful about many unpredictable situations. The case of this study is that Chinese seller(beneficiary) initiated a civil suit against Industrial Bank of Korea to Chinese court and Chinese courts in the first and second trials judged that the notice of payment refusal by Industrial bank of Korea doesn't satisfy Article 16, (c) (ii) (iii) in UCP 600. However, Industrial Bank of Korea implements the judgement even though the judgement is highly biased to Chinese seller. Considering the judgement by Chinese courts, the study suggests some countermeasures to Korean companies and banks which opened L/C. First, the issuing bank should describe the contents of discrepancy specifically based on Article 16, (c) in UCP 600. Second, it is necessary to insert a clause regarding governing law in the L/C contract like sales contract. Third, considering the biased judgement by Chinese court and difficulty in execution of foreign judgement in China, it is recommended to using arbitration as a method of dispute resolution such as ICLOCA and DOCDEX Rules which are international system operated by international instruments because it has legal effects to parties in L/C contracts if the issuing bank inserts arbitration clause in L/C.

• Journal of Korean Society of Disaster and Security
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• v.16 no.2
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• pp.57-63
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• 2023

Recently, Heavy rains and super typhoons occurred by climate change cause a lot of damage in Korea. In order to reduce such damage, various types of river maintenance projects are being promoted, but it is difficult to maintain the balance of rivers in Korea with distinct flood and dry seasons. In particular, river structures installed as a river maintenance project cause various problems such as scouring of structures and their foundations during floods and river bed changes. In order to reduce such bed scour, various vanes are installed in the bend of the river, and various bed scour reduction effects appear depending on the size, arrangement, and shape of the vanes. The vane regenerates the secondary flow in the opposite direction to the secondary flow generated by the centrifugal force, thereby reducing scour around the outer bed and promoting deposition. The theory of this study uses the governing equation applying the continuity equation that satisfies the law of conservation of mass and the momentum equation that satisfies the conservation of momentum, and measures the overall average flow velocity change rate according to design factors to investigate the effect of vanes under various conditions. Both the average and cross-sectional flow velocities decreased in both the trapezoidal vane and the square vane. In addition, vanes installed perpendicularly or inclined to the direction of river flow generate a secondary flow in the opposite direction to the secondary flow generated by centrifugal force, thereby canceling the secondary flow of centrifugal force, so the effect of the vane appears.

• The Journal of the Acoustical Society of Korea
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• v.42 no.6
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• pp.519-528
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• 2023

The aim of this study was to enhance the flow rate and noise performance of a centrifugal pump in dishwashers by designing an optimized impeller shape through numerical and experimental investigations. To evaluate the performance of the target centrifugal pump, experiment was conducted using a pump performance tester and noise experiment was carried out in a semi-anechoic chamber with microphones and a reflecting wall behind the dishwasher. Through the use of advanced computational fluid dynamics techniques, numerical simulations were performed to analyze the flow and aeroacoustics performance of our target centrifugal pump impeller. To achieve this, numerical simulations were carried out using the Reynolds-Average Navier-Stokes equations and Ffowcs-Willliams and Hawkings equations as governing equations. In order to ensure the validity of numerical methods, a thorough comparison of numerical results with experimental results. After having confirmed the reliability of the current numerical method of this study, the optimization of the target centrifugal pump impeller was conducted. An improvement in flow rate was confirmed numerically, and a manufactured proto-type of the optimized model was used for experimental investigation. Furthermore, it was observed that by applying the fan law, we could effectively reduce noise levels without reducing the flow rate.

• Journal of Korea Water Resources Association
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• v.56 no.12
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• pp.939-953
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• 2023

Shallow water equations (SWE) serve as fundamental equations governing the movement of the water. Traditional numerical approaches for solving these equations generally face various challenges, such as sensitivity to mesh generation, and numerical oscillation, or become more computationally unstable around shock and discontinuities regions. In this study, we present a novel approach that leverages the power of physics-informed neural networks (PINNs) to approximate the solution of the SWE. PINNs integrate physical law directly into the neural network architecture, enabling the accurate approximation of solutions to the SWE. We provide a comprehensive methodology for formulating the SWE within the PINNs framework, encompassing network architecture, training strategy, and data generation techniques. Through the results obtained from experiments, we found that PINNs could be an accurate output solution of SWE when its results were compared with the analytical method. In addition, PINNs also present better performance over the Artificial Neural Network. This study highlights the transformative potential of PINNs in revolutionizing water resources research, offering a new paradigm for accurate and efficient solutions to the SVE.

• Journal of Korea Port Economic Association
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• v.22 no.4
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• pp.1-17
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• 2006

In the Bill of Lading of The Irbenskiy Proliv is not subject to the Hague-Visby Rules in accordance with paragraphs (A) and/or (E) of cl.1 or to the Hague Rules in accordance with paragraphs (B) and/or (D) of cl.1. The Irbenskiy Proliv is very rare case that is effective to exempt the carrier as literal words of Bill of Lading. The action concerns cargoes of perishable goods shipped from Brazil to Japan, under Bills of Lading each of which contained an extensive carrier's exemption clause. A preliminary issue was ordered to be determined on the question whether c1.4 is effective to exempt the ralliers from any potential liability for the claims in this case. The court held that there is no reason to reject c1.4 as part of each of the contracts contained in or evidenced by the bills of lading; and it protects the carrier where damage to the goods shipped results from such causes. It is therefore effective to exempt the carriers from any potential liability for those claims.