• Journal of the Korean Society for Aviation and Aeronautics
• /
• v.18 no.3
• /
• pp.42-54
• /
• 2010

The purpose of this study is to analyze the aircraft icing index of Korean peninsula using the numerical weather prediction model, KWRF and pilot weather report data. As comparing the pilot weather report data with the calculated icing index using the KWRF model result, SCLW, RAP, and AFGWC index are more useful than any other index, and IC2, NAWAU, and RSID index are different case by case. But IC1, SID1 and SID2 index show that these overestimated severe icing in every vertical level. Through this icing study, it is expected that this study will help to develop the proper icing index of Korean peninsula.

• Structural Engineering and Mechanics
• /
• v.67 no.4
• /
• pp.327-336
• /
• 2018

In this study, an efficient damage index is proposed to identify multiple damage cases in structural systems using the concepts of frequency response function (FRF) matrix and strain energy of a structure. The index is defined based on the change of strain energy of an element due to damage. For obtaining the strain energy stored in elements, the columnar coefficients of the FRF matrix is used. The new indicator is named here as frequency response function strain energy based index (FRFSEBI). In order to assess the performance of the proposed index for structural damage detection, some benchmark structures having a number of damage scenarios are considered. Numerical results demonstrate that the proposed index even with considering noise can accurately identify the actual location and approximate severity of the damage. In order to demonstrate the high efficiency of the proposed damage index, its performance is also compared with that of the flexibility strain energy based index (FSEBI) provided in the literature.

• International Journal of Contents
• /
• v.3 no.1
• /
• pp.19-23
• /
• 2007

Recently, several main-memory index structures have been proposed to reduce the impact of secondary cache misses. In mainmemory storage systems, secondary cache misses have a substantial effect on the performance of index structures. However, recent studies still stiffer from secondary cache misses when visiting each level of index tree. In this paper, we propose a new index structure that minimizes the total amount of cache miss latency. The proposed index structure prefetched grandchildren of a current node. The basic structure of the proposed index structure is based on that of the CSB+-Tree, which uses the concept of a node group to increase fan-out. However, the insert algorithm of the proposed index structure significantly reduces the cost of a split. The superiority of our algorithm is shown through performance evaluation.

• Journal of the Korean Institute of Telematics and Electronics B
• /
• v.32B no.8
• /
• pp.1091-1098
• /
• 1995

This paper proposes an efficient noiseless encoding method of vector quantization(VQ) index using a dynamic index mapping. Using high interblock correlation, the proposed index mapper transforms an index into a new one with lower entropy. In order to achieve good performance with low computational complexity, we adopt 'the sum of differences in pixel values on the block boundaries' as the cost function for index mapping. Simulation results show that the proposed scheme reduces the average bitrate by 40 - 50 % in ordinary VQ system for image compression. In addition, it is shown that the proposed index mapping method can be also applied to mean-residual VQ system, which allows the reduction of bitrate for VQ index by 20 - 30 %(10 - 20 % reduction in total bitrate). Since the proposed scheme is one for noiseless encoding of VQ index, it provides the same quality of the reconstructed image as the conventional VQ system.

• Proceedings of the KSR Conference
• /
• 2007.11a
• /
• pp.1657-1667
• /
• 2007

This study propose a model for railway safety evaluation with which the safety of whole railway system can be evaluated. The evaluation model is to generate a safety index which quantitatively represent the degree of railway safety. Safety index is proposed a function of three indexes; an accident index, safety management index, and safety culture index. This paper describes the first result from the study on the safety target which will be a key starting point toward the development of safety evaluation model. It is recommended that the safety target be composed of several sub-targets that are apportioned to constituent components. It is concluded that the classification of safety target influence on deciding components or attributes that constitute each sub-indexes; an accident index, safety management index, and safety culture index. Based on this study, a railway safety evaluation model will be developed in the next study.

• Asian Pacific Journal of Cancer Prevention
• /
• v.14 no.5
• /
• pp.2819-2822
• /
• 2013

In this study, antiproliferative effects of the selective estrogen receptor modulator Tamoxifen and the aromatase inhibitor letrozole (Femara) were evaluated and compared using the FM3A cell line, originating from a C3H mouse mammary carcinoma and positive in terms of estrogen receptor (ER) expression. Cell kinetic parameters including labelling index, mitotic index and labelling index were assessed after exposure of the. FM3A cell line to $0.001{\mu}g/ml$ of Tamoxifen and $0.25{\mu}g/ml$ of Femara for 4, 8, 16 and 32 h for all parameters. The results showed that cell growth was inhibited by both agents. There was a significant decrease in labelling index and mitotic index and significant increase in apoptotic index for all experimental groups. The differences between control and all experimental groups were statistically significant (p<0.001) for all applications.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2005.05a
• /
• pp.11-14
• /
• 2005

데이터베이스 성능이 저하되면, 가장 먼저 SQL 튜닝을 고려한다. SQL 튜닝에서 가장 주의 깊게 사용 해야하는 부분이 바로 Index의 설정과 관련된 부분이다. 본 논문에서 OLAP 환경에서 다양하고 복잡한 질의처리 요구와 관련하여, B-Tree Index의 문제점을 개선하고 질의 성능을 향상시키기 위해서 Bitmap Index를 사용하였다. 또한, Bitmap Index 사용의 최적 임계점을 추적하기 위하여, 데이터 분포도와 조건절의 복잡도를 조사하였으며, 샘플링된 질의문을 기준으로 B-Tree Index를 사용하였을 때와 Bitmap Index를 사용하였을 때의 비교 실험을 통하여 Bitmap Index의 사용으로 RDBMS의 성능향상이 있음을 증명하였다.

• The Korean Journal of Ecology
• /
• v.19 no.3
• /
• pp.223-230
• /
• 1996

Five measurements of species diversity (richness index, diversity index, evenness index, dominance index and species sequences-importance curve) and their relationships with sltitude, tree age and community type were studied in $T\v{o}gyusan$ National Park, Korea. Altitude and tree age were the major variables explaining the differences of species diversity in the whole forest. Species richness index, diversity index and evenness index of Quercus mongolica and Pinus densiflora communities were lower than those of Carpinus laxiflora, Q. serrata, Fraxinus mandshurica, Q. mongolica - P. densiflora communities than that in the other communities. The species sequence-importance curve of the forest communities in $T\v{o}gyusan$ coincided with the ideal curve calculated by the lognormal-distribution theory.

• Kyungpook Mathematical Journal
• /
• v.61 no.1
• /
• pp.61-74
• /
• 2021

Let G = (V, E) be a connected graph. The eccentric connectivity index of G is defined by ��C (G) = ∑u∈V (G) deg(u)e(u), where deg(u) and e(u) denote the degree and eccentricity of the vertex u in G, respectively. In this paper, we introduce a new formulation of ��C that will be called the distance eccentric connectivity index of G and defined by $${\xi}^{De}(G)\;=\;{\sum\limits_{u{\in}V(G)}}\;deg^{De}(u)e(u)$$ where degDe(u) denotes the distance eccentricity degree of the vertex u in G. The aim of this paper is to introduce and study this new topological index. The values of the eccentric connectivity index is calculated for some fundamental graph classes and also for some graph operations. Some inequalities giving upper and lower bounds for this index are obtained.

• Journal of the Chungcheong Mathematical Society
• /
• v.35 no.3
• /
• pp.205-225
• /
• 2022

In this paper, we derive analytical closed results for the first (a, b)-KA index, the Sombor index, the modified Sombor index, the first reduced (a, b)-KA index, the reduced Sombor index, the reduced modified Sombor index, the second reduced (a, b)-KA index and the mean Sombor index mSO_α for the OTIS biswapped networks by considering basis graphs as path, wheel graph, complete bipartite graph and r-regular graphs. Network theory plays a significant role in electronic and electrical engineering, such as signal processing, networking, communication theory, and so on. A topological index (TI) is a real number associated with graph networks that correlates chemical networks with a variety of physical and chemical properties as well as chemical reactivity. The Optical Transpose Interconnection System (OTIS) network has recently received increased interest due to its potential uses in parallel and distributed systems.