• ETRI Journal
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• 제25권6호
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• pp.535-537
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• 2003

We propose a rigorous 2D approximation technique for the 3D waveguide structures; it can minimize the well-known approximation errors of the commonly used effective index method. The main concept of the proposed technique is to compensate for the effective cladding index in the equivalent slab model of the original channel waveguide from the modal effective index calculated by the nonuniform 2D finite difference method. With simulations, we used the proposed technique to calculate the coupling characteristics of a directional coupler by the 2D beam propagation method, and the results were almost exactly the same as the results calculated by the 3D beam propagation method.

• 대한수학회논문집
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• 제30권3호
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• pp.283-295
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• 2015

The atom-bond connectivity index of a graph G (ABC index for short) is defined as the summation of quantities $\sqrt{\frac{d(u)+d(v)-2}{d(u)d(v)}}$ over all edges of G. A cactus graph is a connected graph in which every block is an edge or a cycle. The aim of this paper is to obtain the first and second maximum values of the ABC index among all n vertex cactus graphs.

• 대한기계학회논문집B
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• 제29권2호
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• pp.232-238
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• 2005

The 'Mixing Index($D_I$)' is used as a conventional guidance measuring the degree of mixing for multiphase flows. For the case when insoluble solutions flow in a passive micromixer, a new method to calculate $D_I$ is proposed. The 'Vortex Index(${\Omega}_I$)' is suggested and formulated. We infer that ${\Omega}_I$ relates to the degree of chaotic advection. Various arbitrary shaped microchannels were tested to calculate the $D_I\;and\;{\Omega}_I$, and then a simple algebraic equation, $D_I=Aexp(B{\Omega}_I)$, is obtained. This equation may be used instead of the conventional partial differential equation, concentration equation, to estimate the degree of mixing.

• Journal of Information Processing Systems
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• 제15권3호
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• pp.655-669
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• 2019

Supplier evaluation is of great significance in green supply chain management. Influenced by factors such as economic globalization, sustainable development, a holistic index framework is difficult to establish in green supply chain. Furthermore, the initial index values of candidate suppliers are often characterized by uncertainty and incompleteness and the index weight is variable. To solve these problems, an index framework is established after comprehensive consideration of the major factors. Then an adaptive weight D-S theory model is put forward, and a fuzzy-rough-sets-AHP method is proposed to solve the adaptive weight in the index framework. The case study and the comparison with TOPSIS show that the adaptive weight D-S theory model in this paper is feasible and effective.

• 호남수학학술지
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• 제42권4호
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• pp.645-651
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• 2020

The distinguishing number (index) D(G) (D'(G)) of a graph G is the least integer d such that G has an vertex labeling (edge labeling) with d labels that is preserved only by a trivial automorphism. The strong product G ☒ H of two graphs G and H is the graph with vertex set V (G) × V (H) and edge set {{(x1, x2),(y1, y2)}|xiyi ∈ E(Gi) or xi = yi for each 1 ≤ i ≤ 2.}. In this paper we study the distinguishing number and the distinguishing index of strong product of two graphs. We prove that for every k ≥ 2, the k-th strong power of a connected S-thin graph G has distinguishing index equal two.

• 대한기관식도과학회:학술대회논문집
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• 대한기관식도과학회 1978년도 제12차 학술대회연제 순서 및 초록
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• pp.8.3-8
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• 1978

부음기관의 기능이 정상인 경우 1,000Hz 이하의 저음역에서 골도관치는 외이도를 폐새 하였을 때와 개방하였을 때 약 20dB의 차이를 나타낸다. 그러나 외이도를 폐색하였을 때나 개방하였을 때 골도관치에 변화가 없으면 전음기관에 병변이 있음을 의미한다. 1891년에 Bing이 처음으로 외이도폐색에 의한 골도검사를 발표한 이래 여러 학자들에 의하여 본검사가 유용한 임상경력검사의 한방법으로서 인정되고Bing test로 알려지고 있다. Sullivan은 1947년에 250Hz, 500Hz, 1,000Hz에서 외이도를 폐색하였을 때와 개방하였을 때의 골도관치의 차이를 합한 것을 "Occlusion Index"라고 명명하였다. 이에 저자들은 bing test의 임상청각학적 의의를 검토하고자 정상인 40이, 만성중이염환자 20이, 감각신경성난청환자 14이를 대상으로 순음청력검사, Bing test및 impedance audiometry를 시행하고 occlusion index와의 상관관계를 검토하여 다음과같은 결과를 얻었다. 1. Occlusion index는 정상인 40좌에서는 $33.10\pm1.68dB,$ 만성중이염환자 20이에서는 $3.10\pm0.69dB,$ 감각신경성난청환자 14이에서는 28.10=4.05 dB이었다. 2. 정상인 40이의 static compliance는 범위가 0.22~0.75cc, 평균치가 0.64cc, 5.D가 0.05이었다. 3. Static compliance가 작을수록 occlusion index는 컸고, static compliance가 클수록 occlusion index 는 작아지는 영향을 나타내고 있음을 관찰하였다.

• 대한수학회지
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• 제34권2호
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• pp.279-284
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• 1997

Let L/F be a finite separable extension of Henselian valued fields with same residue fields $\overline{L} = \overline{F}$. Let D be an inertially split division algebra over L, and let $^cD$ be the underlying division algebra of the corestriction $cor_{L/F} (D)$ of D. We show that the index $ind(^cD) of ^cD$ divides $[Z(\overline{D}) : Z(\overline {^cD})] \cdot ind(D), where Z(\overline{D})$ is the center of the residue division ring $\overline{D}$.

• International Journal of Contents
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• 제1권1호
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• pp.50-58
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• 2005

Generally, multidimensional data such as image and spatial data require large amount of storage space. There is a limit to store and manage those large amounts of data in single workstation. If we manage the data on parallel computing environment which is being actively researched these days, we can get highly improved performance. In this paper, we propose a parallel multidimensional index structure that exploits the parallelism of the parallel computing environment. The proposed index structure is nP(processor)-nxmD(disk) architecture which is the hybrid type of nP-nD and 1P-nD. Its node structure in-creases fan-out and reduces the height of an index. Also, a range search algorithm that maximizes I/O parallelism is devised, and it is applied to k-nearest neighbor queries. Through various experiments, it is shown that the proposed method outperforms other parallel index structures.

• The Korean Journal of Ecology
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• 제25권1호
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• pp.29-31
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• 2002

The purpose of this study is to estimate height growth patterns and site index cuties (base index age 50 years) for Japanese red cedar trees(Cryptomeria japonica D. Don) grown in southern regions of Korea. The Chapman-Richards growth function was selected for stand height prediction using on the results of stem analysis data sets. Anamorphic base age invariant site index cuties were presented based on this height prediction equation. The resulting site index prediction equation can provide an indication of the productivity of the site quality based on Japanese red cedar trees plantation ages planted in southern regions of Korea.

• 한국기술혁신학회:학술대회논문집
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• 한국기술혁신학회 2001년도 춘계학술대회:발표자료
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• pp.389-408
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• 2001

Evaluating the results of National Nuclear R&D projects has critical importance in nuclear management aspect. This paper uses multi-attribute utility theory as a basis for obtaining a value Index to assess the results of nuclear R&D projects and applies the theory to a specific Korean case study. To structure and quantify basic values for the . evaluation, we elicited important attributes, then refined and structured them into a hierarchy. A multi-attribute index is constructed as a multi-attribute utility function, based on value judgments provided by a group of technical experts, policy makers, and decision-makers. The implications of the results are also discussed. We found that the work and results can provide valuable insights for assessment of nuclear R&D consequences.