• Title/Summary/Keyword: L-S theory

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In situ Structural Investigation of Iron Phthalocyanine Monolayer Adsorbed on Electrode Surface by X-ray Absorption Fine Structure

  • Kim, Seong Hyeon;Toshiaki Ohta;Gang, Gwang Hun
    • Bulletin of the Korean Chemical Society
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    • v.21 no.6
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    • pp.588-594
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    • 2000
  • Structural changes of an iron phthalocyanine (FePC) monolayer induced by adsorption and externally applied potential on high area carbon surface have been investigated in situ by iron K-edge X-ray absorption fine structure (XAFS) in 0.5 M $H_2S0_4.$ Fine structures shown in the X-ray absorption near edge structure (XANES) for microcrystalline FePC decreased upon adsorption and further diminished under electrochemical conditions. Fe(II)PC(-2) showed a 1s ${\rightarrow}$ 4p transition as poorly resolved shoulder to the main absorption edge rather than a distinct peak and a weak 1s ${\rightarrow}$ 3d transition. The absorption edge position measured at half maximum was shifted from 7121.8 eV for Fe(lI)PC(-2) to 7124.8 eV for $[Fe(III)PC(-2)]^+$ as well as the 1s ${\rightarrow}$ 3d pre-edge peak being slightly enhanced. However, essentially no absorption edge shift was observed by the 1-electron reduction of Fe(Il)PC(-2), indicating that the species formed is $[Fe(II)PC(-3)]^-$. Structural parameters were obtained by analyzing extended X-ray absorption fine structure (EXAFS) oscillations with theoretical phases and amplitudes calculated from FEFF 6.01 using multiple-scattering theory. When applied to the powder FePC, the average iron-to-phthalocyanine nitrogen distance, d(Fe-$N_p$) and the coordination number were found to be 1.933 $\AA$ and 3.2, respectively, and these values are the same, within experimental error, as those reported ( $1.927\AA$ and 4). Virtually no structural changes were found upon adsorption except for the increased Debye-Wailer factor of $0.005\AA^2$ from $0.003\AA^2.$ Oxidation of Fe(II)PC(-2) to $[Fe(III)PC(-2)]^+$ yielded an increased d(Fe-Np) (1 $.98\AA)$ and Debye-Wailer factor $(0.005\AA^2).$ The formation of $[Fe(II)PC(-3)]^-$, however, produced a shorter d(Fe-$N_p$) of $1.91\AA$ the same as that of crystalline FePC within experimental error, and about the same DebyeWaller $factor(0.006\AA^2)$.

An Analysis of Ship Turnaround Time in the Port of Inchon (선박재항시간에 대한 분석연구 -인천항의 경우-)

  • Baik, In-Hum
    • Journal of Fisheries and Marine Sciences Education
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    • v.10 no.1
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    • pp.1-14
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    • 1998
  • Transportation provides an infrastructure vital to economic growth, and it is also an integral part of production. As a port is regarded as the interface between the maritime transport and domestic transport sectors, it certainly play a key role in any economic development. Ship's delay caused by port congestion has recently has recently attracted attended with the analysis of overall operation in port. In order to analyse complicated port operation which contains large number of variable factors, queueing theory is needed to be adopted, which is applicable to a large scale transportation system in chiding ship's delay in Inchon port in relation to ship's delay problem. The overall findings are as follows ; 1. The stucture of queueing model in this port can be represented as a complex of multi-channel single-phase 2. Ship's arrival and service pattern were Poisson Input Erlangian Service. 3. The suitable formula to calculate the mean delay in this port, namely, $W_q={\frac{{\rho}}{{\lambda}(1-{\rho})}}{\frac{e{\small{N}}({\rho}{\cdot}N)}{D_{N-1}({\rho}{\cdot}N)}}$ Where, ${\lambda}$ : mean arrival rate ${\mu}$ : mean servicing rate N : number of servicing channel ${\rho}$ : utilization rate (l/Nm) $e{\small{N}}$ : the Poisson function $D_{(n-1)}$ : a function of the cumulative Poisson function 4. The utility rate is 95.0 percents in general piers, 75.39 percents in container piers, and watiting time 28.43 hours in general piers, 13.67 hours in container piers, and the length of queue is 6.17 ships in general piers, 0.93 ships in container piers, and the ship turnaround time is 107.03 hours in general piers, 51.93 hours in container piers.

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Storage Assignment for Variables Considering Efficient Memory Access in Embedded System Design (임베디드 시스템 설계에서 효율적인 메모리 접근을 고려한 변수 저장 방법)

  • Choi Yoonseo;Kim Taewhan
    • Journal of KIISE:Computer Systems and Theory
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    • v.32 no.2
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    • pp.85-94
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    • 2005
  • It has been reported and verified in many design experiences that a judicious utilization of the page and burst access modes supported by DRAMs contributes a great reduction in not only the DRAM access latency but also DRAM's energy consumption. Recently, researchers showed that a careful arrangement of data variables in memory directly leads to a maximum utilization of the page and burst access modes for the variable accesses, but unfortunately, found that the problems are not tractable, consequently, resorting to simple (e.g., greedy) heuristic solutions to the problems. In this parer, to improve the quality of existing solutions, we propose 0-1 ILP-based techniques which produce optimal or near-optimal solution depending on the formulation parameters. It is shown that the proposed techniques use on average 32.2%, l5.1% and 3.5% more page accesses, and 84.0%, 113.5% and 10.1% more burst accesses compared to OFU (the order of first use) and the technique in [l, 2] and the technique in [3], respectively.

Antioxidant and Xanthine Oxidase Inhibitory Activities of Hot Water Extracts of Medicinal Herbs (한약재 열수추출물의 항산화 활성 및 Xanthine Oxidase 저해 활성)

  • Shin, Yu-Jin;Hwang, Jeong-Man;Lee, Seung-Cheol
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.42 no.10
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    • pp.1712-1716
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    • 2013
  • In our study, as many as 29 edible medicinal herbs were selected for testing their ability in the effective treatment of gout based on oriental medicine theory. We extracted each medicinal herb (135 g) with 4 L of distilled water at $100{\sim}105^{\circ}C$ for 210 min. Thereafter, we evaluated both the antioxidant and xanthine oxidase inhibition activities of the extracts obtained. Among all the edible medicinal herbs used in our study, only the extract from Scutellaria baicalensis Georgi (Korean name: hwang-geum) showed (1) the maximum total phenolic content (TPC) (2.25 mg gallic acid equivalent/mL), (2) DPPH radical scavenging activity (94.04%), and (3) xanthine oxidase inhibition activity (87.75%). We also observed that TPC was relatively highly correlated with both the DPPH radical scavenging activity (r=0.63) and xanthine oxidase inhibition activity (r=0.77). Our results suggest that S. baicalensis G. may be a potent antioxidant source for the extraction and development of nutraceuticals that may be utilized for effective treatment of gout.

Maximizing the Selection Response by Optimal Quantitative Trait Loci Selection and Control of Inbreeding in a Population with Different Lifetimes between Sires and Dams

  • Tang, G.Q.;Li, X.W.;Zhu, L.;Shuai, S.R.;Bai, L.
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.11
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    • pp.1559-1571
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    • 2008
  • A rule was developed to constrain the annual rate of inbreeding to a predefined value in a population with different lifetimes between sires and dams, and to maximize the selection response over generations. This rule considers that the animals in a population should be divided into sex-age classes based on the theory of gene flow, and restricts the increase of average inbreeding coefficient for new offspring by limiting the increase of the mean additive genetic relationship for parents selected. The optimization problem of this rule was formulated as a quadratic programming problem. Inputs for the rule were the BLUP estimated breeding values, the additive genetic relationship matrix of all animals, and the long-term contributions of sex-age classes. Outputs were optimal number and contributions of selected animals. In addition, this rule was combined with the optimization of emphasis given to QTL, and further increased the genetic gain over the planning horizon. Stochastic simulations of closed nucleus schemes for pigs were used to investigate the potential advantages obtained from this rule by combining the standard QTL selection, optimal QTL selection and conventional BLUP selection. Results showed that the predefined rates of inbreeding were actually achieved by this rule in three selection strategies. The rule obtained up to 9.23% extra genetic gain over truncation selection at the same rates of inbreeding. The combination of the extended rule and the optimization of emphasis given to QTL allowed substantial increases in selection response at a fixed annual rate of inbreeding, and solved substantially the conflict between short-term and long-term selection response in QTL-assisted selection schemes.

A study of fast Reliability evaluation for acyclic digraph using domination theory (Domination 이론을 이용한 acyclic digraph의 빠른 신뢰도 계산을 위한 연구)

  • 이광원
    • Journal of the Korean Society of Safety
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    • v.11 no.1
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    • pp.27-38
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    • 1996
  • The aim of this paper is to develop more fast algorithm for evaluation of the reliability of networks and system. It is illustrated with examples. This paper derived the algorithm to calculate the acyclic directed graph G(deals with the problem of the s-t graph). The language PASCAL was used to implement the algorithm. Three Examples are calculated and the calculation time is shorter than the time by program in $\ulcorner$21$\lrcorner.

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Simulation-Based Determination of Hydrodynamic Derivatives and 6DOF Motion Analysis for Underwater Vehicle (시뮬레이션 기반 수중 운동체의 유체력 미계수 결정 및 6자유도 운동해석)

  • Go, Gwangsoo;Ahn, Hyung Taek;Ahn, Jin-Hyeong
    • Journal of Ocean Engineering and Technology
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    • v.31 no.5
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    • pp.371-377
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    • 2017
  • This paper introduces a simulation-based determination method for hydrodynamic derivatives and 6DOF (degrees-offreedom) motion analysis for an underwater vehicle. Hydrodynamic derivatives were derived from second-order modulus expansion and composed of the added mass, and linear and nonlinear damping coefficients. The added mass coefficients were analytically obtained using the potential theory. All of the linear and nonlinear damping coefficients were determined using CFD simulation, which were performed for various cases based on the actual operating condition. Then, the linear and nonlinear damping coefficients were determined by fitting the CFD results, which referred to 6DOF forces and moments acting on an underwater vehicle, with the least square method. To demonstrate the applicability of the current study, 6DOF simulations for three different scenarios (L-, U-, and S-turn) were carried out, and the results were validated on the basis of physical plausibility.

Analysis of Ontological Representation of AOS Game Character - focused on - (AOS 게임 캐릭터의 존재론적 재현 양상 분석 - <리그 오브 레전드>를 중심으로 -)

  • Han, Hye-Won;Koo, Hye-In
    • Journal of Korea Game Society
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    • v.15 no.1
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    • pp.185-198
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    • 2015
  • The purpose of this study is to analyze representation of characters of AOS online-game in order to find out the meanings of ontological game characters. This study selects characters of on-line game to analyze representations of game characters by Pierre L$\acute{e}$vy's ontological theory. The characters which represented in on-line games reproduced by costume play in off-line world reflect human desire and construct human existence. Online game character is an existing substance, which could expand human experiences by crossing virtual game world and reality in digital era.

A Study on the Organization and Contents of "CheongKangEuiGam" (『청강의감』의 구성과 내용)

  • Oh, Junho
    • The Journal of Korean Medical History
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    • v.27 no.2
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    • pp.63-74
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    • 2014
  • The purpose of this study is to investigate the organization and contents of "CheongKangEuiGam" and raise interests in study on Oriental Medicine in the 20th century. Songjae, LeeJongHyeong was a disciple of Cheongkang and published this book in 1984 by organizing the medical theory of Cheongkang, KimYoungHoon who lived in the turbulent period from the late period of Joseon to a chaotic state of Korea after the independence of Korea. Even though it is relatively recently published, it is a very important clinical book as well as historical material to look at the aspects of Oriental Medicine in the 20th century. The book contains several notable medical thoughts. First, you can look at one perspective of the 20th century Oriental Western medical study which is initiated by the introduction of Western Medicine in classification schemes and description of disease symptoms. In addition, he uses medicinal herbs such as Cyperus rotundus L., Pinellia ternate(Thunb.) Breit., Poria cocos Wolf, Angelica gigas Nakai, Cnidium officinale, and Paeonia lactiflora Pall as important items, it is found that qi and blood depressed gallbladder is considered as the main pathology of the disease. In terms of names and meaning of prescriptions, he prefers to use mild medicinal herbs rather than intense medicinal herbs. It seems that he tries to help people's lives with cheap and effective medicinal herbs.

Buckling of axial compressed cylindrical shells with stepwise variable thickness

  • Fan, H.G.;Chen, Z.P.;Feng, W.Z.;Zhou, F.;Shen, X.L.;Cao, G.W.
    • Structural Engineering and Mechanics
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    • v.54 no.1
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    • pp.87-103
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    • 2015
  • This paper focuses on an analytical research on the critical buckling load of cylindrical shells with stepwise variable wall thickness under axial compression. An arctan function is established to describe the thickness variation along the axial direction of this kind of cylindrical shells accurately. By using the methods of separation of variables, small parameter perturbation and Fourier series expansion, analytical formulas of the critical buckling load of cylindrical shells with arbitrary axisymmetric thickness variation under axial compression are derived. The analysis is based on the thin shell theory. Analytic results show that the critical buckling load of the uniform shell with constant thickness obtained from this paper is identical with the classical solution. Two important cases of thickness variation pattern are also investigated with these analytical formulas and the results coincide well with those obtained from other authors. The cylindrical shells with stepwise variable wall thickness, which are widely used in actual engineering, are studied by this method and the analytical formulas of critical buckling load under axial compression are obtained. Furthermore, an example is presented to illustrate the effects of each strake's length and thickness on the critical buckling load.