• Journal of Korean Society on Water Environment
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• v.35 no.1
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• pp.19-27
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• 2019

The purpose of this study is to evaluate the water quality and phytoplankton community in Bukhan River which account for 44.4 % of the total inflow into Lake Paldang, using multivariate statistical techniques (i.e., correlation analysis, principal component analysis (PCA)/factor analysis (FA)). Water samples were collected from March to November 2015 and the following parameters measured; water temperature, pH, DO, EC, SS, BOD, Chl-a, COD, TN, $NO_3-N$, $NH_3-N$, TP, DTP, $PO_4-P$, and phytoplankton community. The water quality of the main stream and the tributaries were not significantly different apart from the relatively high concentration of BOD, COD and nutrients recorded in MH. The highest cell density of Stephanodiscus hantzschii and Merismopedia glauca dominated phytoplankton was observed in PD. Based on the correlation analysis, total phytoplankton and cyanophyceae were highly correlated with BOD, COD and nutrients. PCA/FA resulted in four main factors accounting for 82.240 % of the total variance in the water quality dataset. The group of component 1 (TN, DTN, DO, $NO_3-N$, water temperature) and component 2 ($PO_4-P$, T-P, DTP, SS) were classified as nutrient element factor whereas component 3 (Chl-a, COD, BOD, $NH_3-N$, pH) was related to organic substances. Hence, the identification of the main potential environmental pollution factors in Bukhan River will help policy makers make better and more informed decisions on how to improve the water quality.

• Journal of the Korean Mathematical Society
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• v.33 no.2
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• pp.227-234
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• 1996

Consider nonlinear autoregressive processes of order 1 defined by the random iteration $$ (1) X_{n + 1} = f(X_n) + \epsilon_{n + 1} (n \geq 0) $$ where f is real-valued Borel measurable functin on $R^1, {\epsilon_n : n \geq 1}$ is an i.i.d.sequence whose common distribution F has a non-zero absolutely continuous component with a positive density, $E$\mid$\epsilon_n$\mid$ < \infty$, and the initial $X_0$ is independent of ${\epsilon_n : n > \geq 1}$.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.1
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• pp.79-86
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• 2003

In this paper, the effect of oxygen component in fuel on the exhaust emissions has been investigated fur direct injection diesel engine. It was tested to estimate change of engine performance and exhaust emission characteristics for the commercial diesel fuel and oxygenated blended fuel which has seven kinds of mixed ratio. And, the effects of exhaust gas recirculation(EGR) on the characteristics of NOx emission have been investigated. Ethylene glycol mono-n-butyl ether(EGBE) contains oxygen component 27% in itself, and it is a kind of effective oxygenated fuel of mono-ether group that the smoke emission and unburned hydrocarbons of EGBE is reduced remarkably compared with commercial diesel fuel, that is, it can supply oxygen component sufficiently at higher loads and speeds in diesel engine. It was found that simultaneous reduction of smoke and NOx was achieved with oxygenated fuel and cooled EGR method.

• Textile Coloration and Finishing
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• v.22 no.1
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• pp.1-7
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• 2010

The five new red disperse dyes for unmodified pure polypropylene fibers were synthesized. As a coupling component, a di-n-hexyl substituent was used in common, while various substituents were used for the diazo component. The dye having electron donating group at diazo component showed hypsochromic shift compared to the unsubstituted dye, while the dyes having electron withdrawing groups showed bathochromic shift. Owing to their extreme hydrophobicity caused by the di-n-hexyl substituent, all dyes exhibited very high affinity toward pure polypropylene fibers. Fastness to washing was very good for all dyes and fastness to light was good except two purplish red dyes.

• Journal of Korean Institute of Industrial Engineers
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• v.21 no.4
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• pp.555-570
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• 1995

We consider a preventive replacement policy for a cold-standby system with N components, in which only one component is in operation at a time. If the component in operation fails, a standby component is immediately switched into operation. If all components fail, the system fails. The system is inspected at random poins in time to determine whether it is to be replaced or not. If the number of failed components at the time of inspection exceeds a threshold value r, the system is replaced. Otherwise the decision is put off until the next inspection point arrives. Under the cost structure which includes a replacement cost, a system down-time cost and a holding cost of the components, we develop an efficient procedure to find the optimal control values N and r, which minimize the expected cost per unit time.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.345-346
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• 2007

In this study, an experimental method to be able to induce the evoked potential which was reflecting the activity of brain was designed, when the electromagnetic wave was exposed at human or not. The influence of the electromagnetic wave on each component of the evoked potential was discussed. Each component of N100, P100, N200, P300 and so on of the evoked potential was measured in the designed experimental method, And it was observed that the difference existed at each component when the electromagnetic wave was exposed and not exposed.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 1999.11a
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• pp.59-63
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• 1999

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2000.04a
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• pp.69-72
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• 2000

기판과의 동시소성에 의한 고주파 MCM-C(Multi-Chip-Module-Cofired)용 저항을 제작하고 6 GHz 까지의 RF 특성을 측정하였다. 기판은 저온 소성용 기판으로서 총 8층으로 구성하였으며, 7층에 저항체 및 전극을 인쇄하고 Via를 통하여 기판의 최상부까지 연결되도록 하였다 저항체 Pastes, 저항체의 크기, Via의 길이 변화에 따라서 저항의 RF 특성은 고주파일수록 더욱 DC 저항값에서부터 변화되는 양상을 보였다. 내부저항의 등가회로를 구현한 결과, 저항은 전송선로, Capacitance 성분이 혼재되어 있는 것으로 나타났으며 전극의 형태에 따라 Capacitance 성분이 많은 차이를 나타내었다.

• Journal of Korea Society of Digital Industry and Information Management
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• v.8 no.2
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• pp.177-188
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• 2012

GIS provides the various analyzing and displaying using diverse spatial data have supported the powerful functionality and friendly user-interface. But, early GIS software is developed as package tool, it have many difficulties with reducing the cost of developing GPS application and satisfying the various user requirements. At present, the developed GPS applications across multiple domains, despite the common features are built separately for each domain in terms of software engineering development followed out waste of time and money expenditure. However, common features between GPS applications, if deployed as a component assembly and reuse components in terms of enabling the two kinds of component-based development can bring out the beneficial results. In this paper, we described the Analysis and design of GPS ApplicationsS based on Component. Each GPS component is composed of many objects accomplish the atomic service processing and cooperate with each other. And, GPS components meets the qualifications of thc low cost of developing GPS application because of the reusability and re-composition.

• International Journal of Computer Science & Network Security
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• v.22 no.9
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• pp.143-148
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• 2022

Component-based software development (CBD) is a methodology that has been embraced by the software industry to accelerate development, save costs and timelines, minimize testing requirements, and boost quality and output. Compared to the conventional software development approach, this led to the system's development being completed more quickly. By choosing components, identifying systems, and evaluating those systems, CBSE contributes significantly to the software development process. The objective of CBSE is to codify and standardize all disciplines that support CBD-related operations. Analysis of the comparison between component-based and scripting technologies reveals that, in terms of qualitative performance, component-based technologies scale more effectively. Further study and application of CBSE are directly related to the CBD approach's success. This paper explores the introductory concepts and comparative analysis related to component-based software engineering which have been around for a while, but proper adaption of CBSE are still lacking issues are also focused.