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SECOND MAIN THEOREM AND UNIQUENESS PROBLEM OF ZERO-ORDER MEROMORPHIC MAPPINGS FOR HYPERPLANES IN SUBGENERAL POSITION

  • Luong, Thi Tuyet;Nguyen, Dang Tuyen;Pham, Duc Thoan
    • Bulletin of the Korean Mathematical Society
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    • v.55 no.1
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    • pp.205-226
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    • 2018
  • In this paper, we show the Second Main Theorems for zero-order meromorphic mapping of ${\mathbb{C}}^m$ into ${\mathbb{P}}^n({\mathbb{C}})$ intersecting hyperplanes in subgeneral position without truncated multiplicity by considering the p-Casorati determinant with $p{\in}{\mathbb{C}}^m$ instead of its Wronskian determinant. As an application, we give some unicity theorems for meromorphic mapping under the growth condition "order=0". The results obtained include p-shift analogues of the Second Main Theorem of Nevanlinna theory and Picard's theorem.

Estimation of Users' Waiting Cost at Container Terminals in Northern Vietnam

  • Duc, Nguyen Minh;Kim, Sung-June;Jeong, Jung-Sik
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2017.11a
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    • pp.27-29
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    • 2017
  • Container terminals in Northern Vietnam have recorded an impressive development in recent years. This development, however, also raises a fierce competition among local container terminals to attract customers. Beside the handling charges, the vessels' waiting cost is also an important factor that drive the opinion of users in choosing appropriate terminal. This research plans to estimate the waiting cost in different container terminals in Northern Vietnam by building regression equation that describe the relationship between the rate of throughput/capacity and waiting cost/TEU. Queuing theory with the application of Poisson distibution is used to estimate the waiting time of arrival vessels and uncertainty theory is applied to estimate the vessel's daily expenses. Previous studies suggested two different formation of the equation and according to the research results, cubic equation is more suitable in the given case. The research results are also useful for further research which require calculation of waiting cost per TEU in each container terminal in Northern Vietnam.

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공공안전 환경을 위한 사물인터넷 통신망 기술 개요

  • Kim, Na-Eon;Nguyen, Duc Lam;Kim, Seo-Hyang;Kim, Jong-Gwon
    • Information and Communications Magazine
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    • v.34 no.6
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    • pp.35-42
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    • 2017
  • 사물 인터넷(IoT: Internet of Things)은 세상의 모든 사물들을 인터넷과 상호 연결하여 사람과 사물, 사물과 사물 간에 언제 어디서나 상호 소통할 수 있도록 하는 기술이다. 사물 인터넷의 네트웍 기술은 통신 인프라 (Infrastructure) 가 없는 환경에서 이기종 다양한 디바이스를 연결하는 기술로서 재난복구 및 구조와 같은 공공안전 분야에도 적용할 수 있는 애드 혹(ad-hoc) 형태의 네트웍 기능을 제공한다. 특히, 사물 인터넷의 특성상 저사양(low power) 기기들의 사용이 증가하고 있기 때문에 여러 표준화 단체에서 사물 인터넷 특성에 따른 요구사항을 지원하기 위한 표준화 활동을 활발하게 진행중이다. 본 고에서는 급변하는 통신 기술 환경에서 공공안전 분야에 적용할 수 있는 사물 인터넷 통신망을 이루기 위해 필요한 수많은 기술 중에서 주목할 필요가 있는 RPL과 TSCH 기술에 대해 소개하고자 한다.

New Records of Psychomyiidae(Insecta: Trichoptera) from Vietnam (베트남산 통날도래과(날도래목)의 미기록종)

  • Hoang, Duc-Huy;Bae, Yeon-Jae
    • Animal Systematics, Evolution and Diversity
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    • v.21 no.2
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    • pp.273-279
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    • 2005
  • An examination of caddisfly materials from the field trips in Vietnam during 2002-2003 resulted in the recognition of the male adult of Tinodes reuse Malicky & Chantaramongkol(new Vietnamese record) and four undetermined species of larvae (Psychomyia VL1, Psychomyia VL2, Paduniella VL1, and Tinodes VL1) in the family Psychomyiidae Genera Psychomyia and Paduniella are recorded from Vietnam for the first time. Material data, descriptions, diagnoses, distributions, and taxonomic remarks are provided.

Study on the applicability of bentonite-mixed dredged sea sand as a water-proof material (벤토나이트를 혼합한 준설해사의 차수재 활용성)

  • Kim, Seo-Ryong;Lee, Duc-Won;Kong, Kil-Yong;Woo, Jeon-Yong;Kim, Hyun-Tae
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 2003.10a
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    • pp.175-178
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    • 2003
  • There is a case to use dredged-sea sand as a filling material because of difficulty of obtaining required filling material for tideland reclamation project from the land. At this time, side slope erosion is occurred because the precipitation falling to the top of bank acts as infiltration water when it pass through inside of the semi-permeable filling section. This study has confirmed the declining effect of permeability by conducting permeability test to the condition of mixing of bentonite to the dredged sea-sand. And also this study has confirmed that the above processed-soil could be used as a water-proof layer to protect infiltration of water through the infiltration flow analysis.

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Study on a New and Effective Fuzzy PID Ship Autopilot

  • Le, Minh-Duc;Nguyen, Lan-Anh
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.1628-1631
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    • 2005
  • Ship Autopilots are usually designed based on the PD and Pill controllers because of simplicity, reliability and easy to construct. However their performance in various environmental conditions is not as good as desired. This disadvantage can be overcome by adjusting works or constructing adaptive controllers. But those methods are complex and not easy to do. This paper presents a new method for constructing a Ship Autopilot based on the combination of Fuzzy Logic Control (FLC) and Linear Control Theory (Pill control). The new Ship Autopilot has the advantages of both the Pill and FLC control methodologies: easy to construct, and optimal control laws can be established based on ship masters' knowledge. Therefore, the new ship autopilot can be well adapted with parameter variations and strong environment effects. Simulation using MATLAB software for a ship with real parameters shows high effectiveness of the Fuzzy Pill autopilot in course keeping and course changing manoeuvres in comparison with the ordinary Pill ship autopilots.

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The Modified Magnetic Properties of $Mn_3Ga$ Ferrimagnet by Stabilizing on GaSb (001)

  • Feng, Wuwei;Dung, Dang Duc;Cho, Sung-Lae
    • Proceedings of the Korean Magnestics Society Conference
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    • 2009.12a
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    • pp.203-203
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    • 2009
  • We report on the epitaxial growth of tetragonal $DO_{22}$-type Mn3Ga films on GaSb (001) using molecular beam epitaxy and the related structural and magnetic properties. The as-studied $Mn_3Ga$ film was found to exhibit relatively small coercivity around 400 Oe, which differs greatly from the hard magnetic properties of $Mn_3Ga$ bulk specimen or films that are normally reported. This difference was probably attributed to the effects of the GaSb (001) substrate that forced the $Mn_3Ga$ film to be two-dimensionlly stabilized in the (114) orientation and thus led to the modified intrinsic properties of $Mn_3Ga$ films. The growth orientation of the Mn3Ga (114)//GaSb (001) also caused the easy magnetocrystalline direction located in the film plane due to the dominant shape anisotropy in the thin films.

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Application of Satisfaction Curve to Concrete Material

  • Kim, Jang-Ho-Jay;Phan, Hung-Duc;Jeong, Ha-Sun;Kim, Byung-Yun
    • Proceedings of the Korea Concrete Institute Conference
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    • 2008.11a
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    • pp.821-824
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    • 2008
  • This paper presents a systematic approach for estimating material performance of concrete mixture design based on satisfaction curves developed from statistical evaluation of existing or newly obtained material property related data. In performance based material design (PBMD) method, concrete material used for construction of a structure is designed considering a structure's specified performance requirements based on its usage and characteristics such as environmental conditions, structure types, expected design life, etc.Satisfaction curves express the probabilities that one component of substrates (i.e., aggregate size, cement content, etc) of concrete mixture will sustain different criterion value for a given concrete mixture design. This study presents a statistical analysis method for setting up concrete material parameter versus concrete criterion relationships in the form of satisfaction curves and for estimating confidence bounds on these satisfaction curves. This paper also presents an analysis method to combine multiple satisfaction curves to form one unique satisfaction curve that can relate the performance of concrete to a single evaluating value. Based on several evaluated mixture design examples for various material properties, the validity of the proposed method is discussed in detail.

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An Expert System for the Diagnosis of the Fault Type and Fault Loaction In the Distribution SCADA System (배전 SCADA 기능을 이용한 고장타입.고장위치 진단 전문가 시스템)

  • Ko, Yun-Seok;Shin, Hyun-Yong;Sheen, Duc-Ko;Lee, Kee-Seo
    • Proceedings of the KIEE Conference
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    • 1999.07c
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    • pp.1413-1415
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    • 1999
  • 배전선로상에서는 상 불평, 고저항 지락사고나 선로탈락이 발생할 수 있다. 또한, 고장 감지기 정보의 불확실성 등으로 배전 SCADA 정보로부터 정확한 사고유형과 사고위치를 확인하는 작업은 매우 어렵다. 따라서 본 연구에서는 배전선로상에서 발생할 수 있는 다양한 사고들에 대해 사고유형과 사고발생 위치를 신속하고 정확하게 추론할 수 있는 전문가 시스템을 제안한다. 전문가 시스템은 배전 SCADA기능과 수집된 데이터를 종합적으로 활용하게 되는데, 특히, 정확한 사고유형 확인을 위해 절분점 감시 메카니즘이 새롭게 채택되며, 또한, 선로사고시 시스템 운영자들의 오류로부터 발생할 수 있는 파급효과를 최소화하기 위해 고장구간의 자동진단 전략이 개발된다.

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