• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.709-713
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• 2008

관로의 수리학적 홍수추적은 정확성을 기할 수 있다는 장점이 있으나 2차원 해석을 할 경우 광범위한 관망의 개별적인 계산이 요구되어 계산시간이나 수월성 측면에서 어려움이 있다. 이에 본 연구에서는 2차원 관망을 1차원으로 전환시키는 방법인 등가하천 개념을 도입하여 도시유역의 유출량 산정에 있어서 여러 지선들을 개별적으로 모의하지 않으면서도 실제 존재하는 지선들의 효과를 고려할 수 있는 방법을 개발하고자 하였다. 등가하천 개념의 관망 적용을 통해 등가관로의 수리기하조건을 유도하였으며 이를 이용하여 관망 간략화 홍수추적을 수행하였다. 등가관로 홍수 추적을 위해 Saint-Venant 방정식에서 유도된 비선형 확산파 방정식이 사용되었으며 이의 수치모의를 위해 양해법을 이용하였다. 본 연구에서는 등가하천 개념 적용을 통해 결정된 군자배수구역의 등가관로 수리매개변수인 파속 및 확산계수를 이용하여 확산파 방정식에 의해 홍수추적을 실시하였고, 그 결과를 SWMM에 의한 2차원 관망 해석결과와 비교하였다. 검토결과 등가관로를 통한 홍수추적결과가 실제 관망분포를 그대로 고려했을 경우를 잘 재현하는 것으로 나타나 등가하천개념의 도시유역 적용성을 확인할 수 있었다.

• Proceeding of KASS Symposium
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• 2008.05a
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• pp.70-73
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• 2008

Because the inclination and crack of stone pagoda structure are caused by the depth difference of soft soil ground and ground subsidence in weak zone, a long-term conservation of stone pagoda structure is difficult. But it is insufficient to analyze the behavior of stone pagoda structure considering soft soil ground in our country. Therefore, we find the structural effect happening in stone pagoda structure by analyzing mechanically a specific of soft soil ground and carry out structural analysis and structural modelling of stone pagoda structure that considers soft soil ground by discrete element method.

• The Journal of the Acoustical Society of Korea
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• v.22 no.6
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• pp.496-504
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• 2003

In this paper, the error tolerance of each array element to ensure a given specified error level for the array pattern is analyzed using the Genetic Algorithm. In the conventional deterministic method for synthesis of sonar way problems the computational resource required in the simulation grows rapidly as the number of way elements increases. To alleviate this numerical inefficiency, the Monte-Carlo method may be considered as an alternative technique for array syntheses. However, it is difficult to apply the method to the synthesis of array patterns because of its relatively lower accuracy in spite of moderate computational complexity. A new analysis method for estimating error tolerances in sonar arrays is Proposed since the Genetic Algorithm has significant promise to efficiently solve way synthesis problems. Through several numerical tests in linear and planar arrays, it is demonstrated that the proposed method can provide accurate results for error tolerances of sonar arrays.

• Proceedings of the KOR-KST Conference
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• 1998.10a
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• pp.11-20
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• 1998

정적 통행배분모형은 도로 건설 등 공급부문에의 적용은 가능하나 통행량 및 혼잡의 시간적 공간적 변화를 고려하지 못하여 수요관리에서는 교통량 및 비용에 대한 관측치와 모형의 결과치가 상이한 문제가 있다. 이에 동적배분모형의 다양한 접근방법이 시도되고 있는데 그 중 Simulation기법을 개발하고자 하였다. 모형은 개별차량의 시공간상 움직임을 포현하고자 절대시간이 가장 이른 차량순으로 시뮬레이션을 함으로써 선입선출(FIFO)을 가능하게 하였다. 각 차량별 지체시간의 계산은 대기행렬 이론을 기초로 한 누적곡선법을 적용하여 도출하였다. 개별차량 Simulation은 시간축으로 확장된 연속류 Network상에서 각 차량의 도착 및 출발할 노드와 시간대를 결정하면 모든 지점에서 누적도착, 출발곡선을 그릴 수 있으며 이를 통해 도로구간에 있어 시간대별 통행시간, 밀도, 속도 등을 파악할 수 있다. 또한 합류부의 용량와 와해현상과 분류부의 용량변화현상 제약 및 Queue길이 제약이 이루어지도록 하였다. 개발된 모형의 검증은 영동대교 북단 강변도로 진출입부 자료를 실측하여 사용하였다. 모형은 합류부 용량와해의 적용 전과 후의 결과를 각각 실측치와 비교하였다. 용량와해현상을 적용한 모형에서 MAPE 10%미만의 우수한 예측력을 보였다. 이는 누적곡선을 이용한 Simulation모형이 현실에 가까움을 의미하는 것이며, 합류부 용량와해현상의 관계식을 보다 정교하게 도출하고 분류부에도 이를 적용한다면 모형의 예측력은 더욱 향상될 것으로 보인다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.766-774
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• 2017

Software has been developed for simulating particle dispersion in a circular pipe with sudden-expansion, which models the fuel feeding system of a combustor that uses metal powder like aluminum as fuel. The Lagrangian based discrete tracer point method was employed for a plug flow of particles that satisfies local turbulent velocity fluctuations. A radial velocity component was created to improve the flow turning outwards in the recirculation zone. The particle distribution patterns from both with and without the component were directly compared with the experiments near the reattachment.

• Journal of Korean Society of Steel Construction
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• v.19 no.6
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• pp.633-642
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• 2007

Although the Load and Resistance Factor Design (LRFD) method is an advanced design approach, it does not accurately capture the interaction between individual members and structural system. A nonlinear inelastic analysis for the entire structure is required to solve this problem. According to many design codes of advanced countries, a nonlinear inelastic analysis can be applied to predict the structural behavior and strength reasonably. In this study, an LRFD design method using practical nonlinear inelastic analysis was proposed. Design examples using the proposed method waspresented, and the economical efficiency and adequacy of the proposed method was investigated by comparing the design results with that of the AISC-LRFD. It has been consequently demonstrated that the proposed method can reduce the construction cost through savings in steel.

• The Korean Journal of Air & Space Law and Policy
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• v.27 no.2
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• pp.29-65
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• 2012

Der neue strukturelle Ansatz der Kommbination eines Rahmen$\ddot{u}$bereinkommens und eines ausr$\ddot{u}$stungsspezifischen Sonderprotokolls bedingt einen neuen organisatorischen Anstz f$\ddot{u}$r die Zusammenarbeit zwischen internationalen Organisationen bei der Schaffung von internationalem Einheitsprivatrecht. So haben hier zwei internationale Organisationen gemeinsam die Verantwortung f$\ddot{u}$r einmultilaterales $\ddot{U}$bereinkommen $\ddot{u}$bernommen: auf der einen Seite UNIDROIT als die internationale Organisation, die generell f$\ddot{u}$r die Vereinheitlichung des Privatrechts kompetent ist; auf der anderen Seite ICAO als die f$\ddot{u}$r die private Luftfahrt zust$\ddot{a}$ndige internationale Organisation. Dieses neue, f$\ddot{u}$r die Luftfahrzeugausr$\ddot{u}$stung praktizierte organisatorische Modell eines joint venture zweier internationaler Organisation bei der Einheitsrechtsetzung, namlich die Betreuung eines allgemeinen privatrechtsvereinheitlichenden Rahmens$\ddot{u}$bereinkommens durch UNIDROIT und die Wahrnehmung der sektorspezifischen Belange in einem ausr$\ddot{u}$stungsspesifischen Sonderprotokoll durch die jeweils zust$\ddot{a}$ndige internationale Spezialorganisation, hat bereits f$\ddot{u}$r die Sektoren der Eisenbahn- und Weltraumausrustung Schule gemacht. Das in Kapstadt beschlossene v$\ddot{o}$lkervertragliche Regelungswerk hat erstmals ein einheitsrechtliches - grunds$\ddot{a}$atzlich weltweite Geltung anstrebendes - Sicherungsrecht geschafen. Dies kann f$\ddot{u}$r die Sachenrechtsintergration einen $\ddot{a}$hnlichen Durchbruch bedeuten, wis das Wiener UN-kaufrechts$\ddot{u}$bereinkommen von 1980 f$\ddot{u}$r das Schuldvertragsrecht. Voraussetzung daf$\ddot{u}$r ist allerdings die juristische Qualit$\ddot{a}$t und Praxisgerechtigkeit des Regelungswerkes und - insbesondere - das Funktionieren des Registersystems. Von wesentlicher Bedeutung f$\ddot{u}$r den Erfolg des $\ddot{U}$bereinkkommens wird auchsein, ob es Rechtssicherheit zu gew$\ddot{a}$hrleisten vermag.

• Journal of Korean Library and Information Science Society
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• v.45 no.4
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• pp.365-390
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• 2014

This study intend to find the application methods of the FRBR model about legislation by analyzing a law life cycle from the enactment to the amendment and abolition of legislation and the type of the change after abolition. The legislation is the work as an aggregate entity consisting legal provisions and each provision is also the work. They are in the Whole-to-Part relation. The legislation has a effect by being published in the official gazette, and the updated text or the translated text is not the official version. Even if the name of the legislation is changed, it is treated as the same entity when it is not abolished and the simple rectifying text expressed in the official gazette is also legally valid. The Libraries Act has been replaced by the Libraries Act(old version), the Libraries Promotion Act, the Libraries and Reading Promotion Act and the Libraries Act(new version) in the order named, and it can be bounded into a superwork. For these examples, we provided the application method of FRBR model and suggested the actual application cases regarding Work, Expression, Manifestation and Item which are in Group 1 of FRBR model for the Libraries Act.

• Analytical Science and Technology
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• v.17 no.4
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• pp.302-307
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• 2004

Determination of actinides in the environmental sample requires separation of each element. This procedure is tedious and time consuming. And also, the detection limits of some nuclides using alpha spectrometry are rather higher. To overcome the lower detection limit and complicated separation procedure, a simple analytical technique for the determination of actinide isotopes in the environmental samples was developed and applied to IAEA and NIST reference sediment samples. For the separation of actinides from matrix, anion exchange resin and TRU-spec extraction chromatography resin were used and chemical yields were obtained using natural uranium, thorium, $^{242}Pu$ and $^{243}Am$ tracers. For overcoming the higher detection limits of U and Th in alpha spectrometry, neutron activation analysis was applied. Using combined method, the detection limit was increased about 10 times. The activity values of each isotope were consistent with the reference values reported by IAEA and NIST.

• Journal of Korea Society of Industrial Information Systems
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• v.29 no.1
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• pp.49-62
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• 2024

In this paper, a sustainable closed-loop supply chain (SCLSC) network model is proposed for domestic mobile phone industry. Economic, environmental and social factors are respectively considered for reinforcing the sustainability of the SCLSC network model. These three factors aim at minimizing total cost, minimizing total amount of CO₂ emission, and maximizing total social influence resulting from the establishment and operation of facilities at each stage of the SCLSC network model. Since they are used as each objective function in modeling, the SCLSC network model can be a multi-objective optimization problem. A mathematical formulation is used for representing the SCLSC network model and a hybrid meta-heuristic approach is proposed for efficiently solving it. In numerical experiment, the performance of the proposed hybrid meta-heuristic approach is compared with those of conventional meta-heuristic approaches using some scales of the SCLSC network model. Experimental results shows that the proposed hybrid meta-heuristic approach outperforms conventional meta-heuristic approaches.