• Bulletin of the Korean Chemical Society
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• v.35 no.5
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• pp.1413-1416
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• 2014

A novel topological index (TG Index) has been introduced. The graphical matrix representation of the TG index includes the use of directed subgraphs for the first time in graph theory literature. The application of the TG index on certain properties of polyenes yielded very well correlation data.

• International Commerce and Information Review
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• v.9 no.2
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• pp.161-182
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• 2007

The objective of this paper is to examine the competitiveness of Korean export firms in EU market. In this study, market share index, RCA index, trade specialization index, and market competitiveness index were used as an analytical tool. On the market share index, Korea had a large market share in the SITC section 7(machinery and transport equipment) market in EU. On the RCA index, Korea appeared to have high export competitiveness in the electrical machinery, apparatus and appliances, n.e.s.(not elsewhere specified[stated]), and electrical parts thereof (77), travel goods, handbags and similar containers(83), textile yarn, fabrics, made-up articles, n.e.s., and related products(65), and iron and steel(67) division. On the trade specialization index, however, Korea appeared to tend to decline generally. On the market competitiveness index, Korea appeared to have competitive advantage in the iron and steel(67), machinery specialized for particular industries(72), office machines and automatic data-processing machines(75), electrical machinery, apparatus and appliances, n.e.s., and electrical parts thereof(77), road vehicles(78), and other transport equipment(79) division; but in 29 divisions, the index indicates that Korean firms' competitiveness was low. Finally, the authors discuss the implications of these findings and offer directions for future study.

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

• Kyungpook Mathematical Journal
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• v.54 no.2
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• pp.263-269
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• 2014

As a further study on reflexive families of subsets, we introduce the reflexive index for a family of subsets of a given set and show that the index of a finite family of subsets of a finite or countably infinite set is always finite. The reflexive indices of some special families are also considered.

• Journal of Environmental Health Sciences
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• v.47 no.2
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• pp.144-154
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• 2021

Objectives: This study was intended to identify hazard contribution by region, media, and chemical by calculating a hazard-based index using pollutant release and transfer register (PRTR) data. Methods: PRTR data for the period 2011 to 2016 was analyzed to examine the regional trends in toxic releases in terms of quantity and to create a corresponding hazard-based index. For the hazard-based index, the Risk-Screening Environmental Indicators (RSEI) Model was used. Results: The results of the trend analysis show that total releases decreased slightly, but health hazard levels increased consistently. According to the outcome of regional contribution analysis of the hazard-based index, Chungcheongnam-do, Jeollabuk-do and Gyeonggi-do Provinces showed a high ratio in the index for air and water release pollutants, while Gyeongsangbuk-do and Gyeongsangnam-do Provinces showed a high ratio in the index of soil release and waste transfer pollutants. Also, as a result of the analysis of the top ranked substances in the hazard-based index, it was found that chromium, cobalt and its compounds, and ethylene oxide contributed greatly to air release substances, while chromium, benzene, and lead and its compounds contributed greatly to water release substances. Conclusion: These results showed considerable disparities between total release and health hazard levels, especially in the analysis of contribution by regions and by chemical substance. Therefore, the hazard-based index should be used both to support a more comprehensive and robust approach to screening of chemicals for environmental health policy and for management.

• Journal of the Korean Mathematical Society
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• v.42 no.5
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• pp.1003-1015
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• 2005

Klein proved that polynomial rings over nil rings of bounded index are also nil of bounded index; while Puczylowski and Smoktunowicz described the nilradical of a power series ring with an indeterminate. We extend these results to those with any set of commuting indeterminates. We also study prime radicals of power series rings over some class of rings containing the case of bounded index, finding some examples which elaborate our arguments; and we prove that R is a PI ring of bounded index then the power series ring R[[X]], with X any set of indeterminates over R, is also a PI ring of bounded index, obtaining the Klein's result for polynomial rings as a corollary.

• Journal of Korean Society for Quality Management
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• v.38 no.1
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• pp.34-41
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• 2010

This paper proposes the compliance collaboration index(CCI) which can be useful to measure the level of supply chain's compliance collaboration quantitatively. It can be shown that the proposed index is quite flexible when applied in real situations at the request of the index user. For instance, even if only one company of many companies in trade supply chain to be tested through the AEO certification test is not satisfied the required specification. the index is designed in such a way that the score can't be higher than a certain predetermined value. The proposed CCI can be used as the guidance for a trade company's collaboration process control strategy to increase the efficiency of compliance improvement activity. In this paper, we use the Analysis Hierarchy Process(AHP) which is one of the methods recommended by ISO/ICE as a measurement of weight to be assigned to the relevant parameters considered in the CCI.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.9
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• pp.1646-1650
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• 2011

SAIDI(System Average Interruption Duration Index) is the index that signifies the power quality of customers. SAIDI is also used to know how well utilities operate their systems. The annual interruption time in the areas that consists of widely distributed customers, is generally longer than that in the areas that consists of heavily concentrated customers. The Reliability index of huge system is not necessarily better or worse than that of small system, because SAIDI is irrelevant to the total amount of power sold or the total number of customers. This paper proposes a customer density very relevant to SAIDI. The proposed customer density is used to modify the existing SAIDI to more clearly express the service level of power supply. A modified WSAIDI(weighted SAIDI) can be a useful indicator helping utilities improve the reliability of their systems and customers evaluate the service level of receiving power.

• Journal of The Korean Society of Agricultural Engineers
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• v.53 no.6
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• pp.165-170
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• 2011

Recently natural disasters such as the frequency and intensity of drought have been increasing as a result of climate change. This study suggests a drought index, WADI (Water Availability Drought Index), that considers water availability using 6 components (water intake, groundwater level, agricultural reservoir water level, dam inflow, streamflow, and precipitation) using the Z score and data monitoring on a nationwide level. SPI (Standardized Precipitation Index) was applied in coastal area. For the severe droughts of 2001 spring and 2008 autumn, the index was evaluated by comparison with reported damage areas. suggested to combine The spatial concordance rate of WADI in 2001 and 2008 for estimation of the degree of drought severity was 50 % and 24 % compared to the actual recorded data respectively.

• The Journal of Information Technology and Database
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• v.8 no.2
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• pp.103-114
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• 2001

In this paper, we propose an efficient index mechanism for real-time main memory database systems. Existing main memory index structures based on the tree can effectively support range searches. However, it doesn't guarantee the real-time characteristic because difference between the access time of a node and an average access time can be high. The index structures based on the hash have always a regular random access time on the simple searches and that speed is very fast. However they do not support range searches. To solve such problems, we propose a new index mechanism called Hyper Tree-Hash (Hyper-TH) that combines ECBH (Extendible Chained Bucket Hashing) and T＊-tree. ECBH can be dynamically extended and has a very fast access time. T＊-tree effectively supports the range searches. We show through our experiments that the proposed mechanism outperforms existing other index structures.