• Journal of Intelligence and Information Systems
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• v.14 no.3
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• pp.133-154
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• 2008

The data imbalance problem which can be uncounted in data mining classification problems typically means that there are more or less instances in a class than those in other classes. In order to solve the data imbalance problem, there has been proposed a number of techniques based on re-sampling with replacement, adjusting decision thresholds, and adjusting the cost of the different classes. In this paper, we study the feasibility of the combination usage of the techniques previously proposed to deal with the data imbalance problem, and suggest a combination method using genetic algorithm to find the optimal combination ratio of the techniques. To improve the prediction accuracy of a minority class, we determine the combination ratio based on the F-value of the minority class as the fitness function of genetic algorithm. To compare the performance with those of single techniques and the matrix-style combination of random percentage, we performed experiments using four public datasets which has been generally used to compare the performance of methods for the data imbalance problem. From the results of experiments, we can find the usefulness of the proposed method.

• Korean Journal of Soil Science and Fertilizer
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• v.49 no.3
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• pp.242-250
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• 2016

Veterinary antibiotics (VAs) has been used to treat animal disease and to increase animal weight as growth promoter. However, abused usage of VAs can cause production of antibiotic resistance genes (ARGs) in the environment and additionally, residual of VAs in soil can be transferred into crops. Therefore, main objective of this research was to examine bioaccumulation of VAs in sprouts (red cabbage, Brassica Olearacea L. var. Capitata f. rubra and red radish, Raphanus sativus) with hydroponic method. Total of 7 VAs in 2 different classes of VAs (tetracyclcines: tetracycline, oxytetracycline, chlortetracycline, sulfonamides: sulfamethoxazole, sulfamethazine, sulfamethiazole, macrolides: tylosin) were evaluated and experiment was conducted with solid phase extraction (SPE)/high performance liquid chromatography tandem mass spectrometry (HPLC/MS/MS). Initial spiked concentration of 7 VAs was $5mg\;L^{-1}$ and cultivation period was 8 days. Result showed that growth of sprouts was inhibited about 23-27% when VAs was introduced. Amount of bioaccumulated VAs was also differed depending on class of VAs. The highest amount of bioaccmulated VAs was tetracycline and sulfamethoxazole in each class with a concentration of 4.05, $7.73mg\;kg^{-1}$ respectively. Calculated transfer ratio of VAs into crops was also ranged 0.38-54.27%. Overall, bioaccumulation of VAs in crops can be varied depending on crop species and class of VAs. However, further research should be conducted to verify bioaccumulation of VAs in crops in the soil environment.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.1
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• pp.178-202
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• 2012

In this paper, we first survey cross-layer architectures for Wireless Sensor Networks (WSNs) and Wireless Multimedia Sensor Networks (WMSNs). Afterwards, we propose a novel cross-layer architecture for QoS provisioning in clustered and multi-hop based WMSNs. The proposed architecture provides support for multiple network-based applications on a single sensor node. For supporting multiple applications on a single node, an area in memory is reserved where each application can store its network protocols settings. Furthermore, the proposed cross-layer architecture supports heterogeneous flows by classifying WMSN traffic into six traffic classes. The architecture incorporates a service differentiation module for QoS provisioning in WMSNs. The service differentiation module defines the forwarding behavior corresponding to each traffic class. The forwarding behavior is primarily determined by the priority of the traffic class, moreover the service differentiation module allocates bandwidth to each traffic class with goals to maximize network utilization and avoid starvation of low priority flows. The proposal incorporates the congestion detection and control algorithm. Upon detection of congestion, the congested node makes an estimate of the data rate that should be used by the node itself and its one-hop away upstream nodes. While estimating the data rate, the congested node considers the characteristics of different traffic classes along with their total bandwidth usage. The architecture uses a shared database to enable cross-layer interactions. Application's network protocol settings and the interaction with the shared database is done through a cross-layer optimization middleware.

• English Language & Literature Teaching
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• v.13 no.1
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• pp.1-26
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• 2007

This study aimed to investigate how EFL learners perceived English writing tasks and teachers' written feedback. The subjects were 82 mixed major college EFL students aged 19-24; the majority were freshmen females. Based on the scores estimated from the essay evaluation test, they were placed into two groups (proficienand less-proficient writers) and responded to an in-class questionnaire. The results indicated that: (1) regardless of writing proficiency, a large number of the students felt that they were just fair writers, which could be derived from low confidence and high anxiety; (2) grammar and vocabulary were perceived as the main features that determined good EFL writers and also prevented the students from performing the writing task successfully; (3) they believed that teachers' feedback contributed to the development of their English writing skills because it helped them apprehend what to improve or avoid in the future, acquire better English usage, and correct their errors; and (4) the proficient writers were more willing to correct errors themselves after being provided clues than the less-proficient writers. Implications of the findings for EFL classrooms are discussed.

• Journal of the Korea Society of Computer and Information
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• v.22 no.2
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• pp.9-19
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• 2017

Useful continuous sensing applications are increasingly emerging as a new class of mobile applications. Meanwhile, open, multi-use sensor devices are newly adopted beyond smartphones, and provide huge opportunities to expand potential application categories. In this upcoming environment, uncoordinated use of sensor devices would cause severe imbalance in power consumption of devices, and thus result in early shutdown of some sensing applications depending on power-hungry devices. In this paper, we propose EnergyCordy, a novel inter-device energy use coordination system; with a system-wide holistic view, it coordinates the energy use of concurrent sensing applications over multiple sensor devices. As its key approach, we propose a relaxed sensor association; it decouples the energy use of an application from specific sensor devices leveraging multiple context inference alternatives, allowing flexible energy coordination at runtime. We demonstrated the effectiveness of EnergyCordy by developing multiple example applications over custom-designed wearable senor devices. We show that EnergyCordy effectively coordinates the power usage of concurrent sensing applications over multiple devices and prevent undesired early shutdown of applications.

• 한국정보교육학회:학술대회논문집
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• 2007.08a
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• pp.209-214
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• 2007

현재 초등 학교의 ICT 활용 교육을 위한 교육 환경과 교수 학습 자료는 일반 학급을 대상으로 한 것이 대부분을 차지하고 있기 때문에 초등 특수 학급 교사들이 ICT를 활용해서 장애 아동들을 가르치는데 큰 어려움을 겪고 있다. 그러나 초등 특수학급을 담당하는 교사와 장애 아동을 위한 ICT 활용 교육 환경과 교수 학습 자료에 대한 연구는 미비한 실정이다. 따라서 본 연구에서는 초등 특수학급 담당 교사와 학생들에게 적절한 ICT 교육 환경과 교수 학습 자료의 개발을 위해 초등 특수학급 교사들의 ICT 교수 학습 자료 활용 실태를 분석 한다.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.53 no.2
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• pp.111-120
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• 2004

This paper presents an application of Unified Modeling Language(UML) software technique for developing transmission pricing evaluation package. Also, this paper describes a transmission pricing algorithm applicable to a large-scale power system. The usage-based transmission pricing mechanism is very complex since it requires power flow analysis, fault current analysis, sensitivity evaluation of a transmission line, penalty factors calculation, transmission asset databases, and cost allocation rules, etc. For the efficient and flexible development of the transmission pricing package, a UML. approach is applied, which is composed of a use-case diagram, interaction diagram, class diagram, and package diagram using Rational Rose Unified Process(RUP). The designed transmission pricing package can be efficiently modified and reused as the market environments evolves since it is designed by Object-Oriented Programming(OOP).

• International Journal of Human Ecology
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• v.4 no.1
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• pp.1-14
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• 2003

This study examines apparel brand extensions in terms of types and leverage effects. The researchers identified types of apparel brand extensions based on recent data gathered from the Korean apparel market. Three hundred forty eight Korean female subjects in their 20's evaluated three hypothetically extended brands from a major casual brand which actually exists in the Korean market. Major findings of the study follow. First, apparel brands are extended to different product categories by adjusting mostly target profiles as well as product usage, product class, and distribution channel. Secondly, leverage effects, the extent of image transfer from the parent brand to extended brands, are different according to the extension types.

• Proceedings of the Korean Information Science Society Conference
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• 1998.10c
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• pp.246-248
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• 1998

본 논문에서는 대화형 시스템을 시험하기 위한 시험 사례를 마코프 연쇄의 통계적 확률 과정으로 생성하는 방안을 제시한다. 객체지향 방법론의 통합안인 UML에서는 클래스도(Class Diagram)가 표현할 수 없었던 시스템의 동적인 관점을 상태 전이도(State Transition Diagram)는 구체적으로 표현할 수 있다. 시스템의 사용법을 상태 전이도로 표현하고, 상태간의 전이 확률(Transition Probability)을 계산하여 사용법 연쇄(Usage Chain)를 구성한다. 사용법 연쇄는 다음 상태가 과거의 상태에 영향을 받지 않고 현시점의 상태에만 의존하는 이산 시간형 확률과정인 마코프 연쇄(Markov Chain)가 된다. 본 논문에서는 사용법 연쇄를 분석하여 상태 전이도의 상태와 원호가 어떤 범위에서 시험될 것인지 결정되었을 때, 사용법 연쇄의 전이 확률이 높은 순서별로 연결하여 시험 사례를 생성하는 방안을 제시하고, 예제를 설명한다.

• Proceedings of the KSRS Conference
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• 2007.10a
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• pp.591-593
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• 2007

This paper is to cluster the AMR (Automatic Meter Reading) data. The load survey system has been applied to record the power consumption of sampling the contract assortment in KEPRI AMR. The effect of the contract assortment change to the customer power consumption is determined by executing the clustering on the load survey results. We can supply the power to customer according to usage to the analysis cluster. The Korea a class of the electricity supply type is less than other country. Because of the Korea electricity markets exists one electricity provider. Need to further divide of electricity supply type for more efficient supply. We are found pattern that is different from supplied type to customer. Out experiment use the Clementine which data mining tools.