• Genomics & Informatics
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• 제7권3호
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• pp.148-151
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• 2009

Generally, larger sample size leads to a greater statistical power to detect a significant difference. We may increase the sample size for both case and control in order to obtain greater power. However, it is often the case that increasing sample size for case is not feasible for a variety of reasons. In order to look at change in power as the ratio of control to case varies (1:1 to 4:1), we conduct association tests with simulated data generated by PLINK. The simulated data consist of 50 disease SNPs and 300 non-disease SNPs and we compute powers for disease SNPs. Genetic Power Calculator was used for computing powers with varying the ratio of control to case (1:1, 2:1, 3:1, 4:1). In this study, we show that gains in statistical power resulting from increasing the ratio of control to case are substantial for the simulated data. Similar results might be expected for real data.

• 대기
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• 제24권1호
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• pp.77-87
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• 2014

The radar reflectivity is significantly affected by ground clutter, beam blockage, anomalous propagation (AP), birds, insects, chaff, etc. The quality of radar reflectivity is very important in quantitative precipitation estimation. Therefore, Weather Radar Center (WRC) of Korea Meteorological Administration (KMA) employed two quality control algorithms: 1) Open Radar Product Generator (ORPG) and 2) fuzzy quality control algorithm to improve quality of radar reflectivity. In this study, an occurrence of AP echoes and the performance of both quality control algorithms are investigated. Consequently, AP echoes frequently occur during the spring and fall seasons. Moreover, while the ORPG QC algorithm has the merit of removing non-precipitation echoes, such as AP echoes, it also removes weak rain echoes and snow echoes. In contrast, the fuzzy QC algorithm has the advantage of preserving snow echoes and weak rain echoes, but it eliminates the partial area of the contaminated echo, including the AP echoes.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1995년도 Proceedings of the Korea Automation Control Conference, 10th (KACC); Seoul, Korea; 23-25 Oct. 1995
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• pp.360-363
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• 1995

In this paper, we describe the composition of frequency response bands based on experimental data of plants (controlled systems) with uncertainty and nonlinearity, and the robust stability evaluation of feedback control systems. Analysis and design of control systems using the upper and lower bounds of such experimental data would be effective as a practicable method which is not heavily dependent upon mathematical models such as the transfer function. First, we present a method to composite gain characteristic bands of frequency response of cascade connected plants with uncertainty and a recurrent inequality for the composition. Next, evaluation methods of the robust stability of multi-loop control systems obtained through feedback from the output terminals and multi-loop control systems obtained through feedback into the input terminals are described. In actual control systems, experimental data of frequency responses often depends on the amplitude of input. Therefore, we present the evaluation method of the nominal value and the width of the frequency response band in such a case, and finally give numerical examples based on virtual experimental data.

• Journal of Biosystems Engineering
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• 제40권3호
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• pp.284-288
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• 2015

Training power tiller operators in safe farming is necessary to avoid farming accidents. With the continuing progress in computational technology, driving simulators have become increasingly popular for conducting such training. Purpose: The objective of this study is to develop mock control devices and data acquisition apparatus for a tiller simulator. Methods: Except for the stand and tail wheel adjusting levers, the mock control devices were developed using a tiller handle assay. The data acquisition apparatus was realized using an embedded data-logging device and LabVIEW, the system design software. Results: The control devices of a real handle assay were successfully mimicked by the mock operator control devices, which used sensors for the relevant measurements. The data from the mock devices were acquired and transmitted to the main computer at intervals of 10 ms via Wi-Fi. Conclusions: The developed mock control devices operate similar to real power tillers and can be utilized in power tiller training simulators.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2006년도 한국컴퓨터종합학술대회 논문집 Vol.33 No.1 (A)
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• pp.250-252
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• 2006

Web technologies are gaining increased importance in automation and control systems. However, the choice of Web technologies depends on the use cases in the application environment. In industrial systems, the data can be got not only from many different field systems and devices but also from different OPC (OLE for Process Control) Servers. Current OPC Client might be able to read simple data from OPC Server, but there are some problems to get structured data and to exchange structured information between collaborating applications. Therefore, OPC Foundation has defined interfaces to OPC XML-DA (OPC XML Data Access) and OPC Complex Data that aim to solve those problems. The OPC XML-DA can facilitate the exchange of plant data across the internet, and upwards into the enterprise domain. In addition, the OPC Complex Data will extend the OPC DA specification to allow the OPC Client to read and decode any type of data from measurement and control systems on the plant floor. This paper will describe the concept of OPC XML-DA and OPC Complex Data. And then it proposes a mechanism to implement the OPC Complex Data into OPC XML-DA Server. Additionally, the paper also discusses the security aspects.

• 제어로봇시스템학회논문지
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• 제14권2호
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• pp.184-190
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• 2008

This paper describes a message model based on XML (eXtensible Markup Language) to present real-time data from sensors and instruments at manufacturing processes for web service. HTML (Hyper Text Markup Language) is inadequate for describing real-time data from process control plants while it is suitable for displaying non-real-time multimedia data on web. For XML-based web service of process data, XML format for the data presentation was proposed after investigating data of various instruments at steel-making plants. Considering transmission delay inevitably caused from increased message length and processing delay from transformation of raw data into defined format, which was critical for operation of a real-time system, its performance was evaluated by simulation. In the simulation, we assumed two implementation models for conducting the transformation function. In one model, transformation was done at an SCC (Supervisory Control Computer) after receiving real-time data from instruments. In the other model, transformation had been carried out at instruments before the data were transmitted to the SCC. Various tests had been conducted under different conditions of offered loads and data lengths and their results were described.

• 제어로봇시스템학회논문지
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• 제6권7호
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• pp.602-610
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• 2000

In communication networks used in safety-critical systems such as control systems in nuclear power plants there exist three types of data traffic : urgent or asynchronous hard real-time data hard real-time periodic data and soft real-time periodic data. it is necessary to allocate a suitable bandwidth to each data traffic in order to meet their real-time constraints. This paper proposes a method to meet the real-time constraints for the three types of data traffic simultaneously under a timer-controlled token bus protocol or the IEEE 802.4 token bus protocol and verifies the validity of the presented method by an example. This paper derives the proper region of the high priority token hold time and the target token rotation time for each station within which the real-time constraints for the three types of data traffic are met, Since the scheduling of the data traffic may reduce the possibility of the abrupt increase of the network load this paper proposes a brief heuristic method to make a scheduling table to satisfy their real-time constraints.

• IEIE Transactions on Smart Processing and Computing
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• 제5권3호
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• pp.199-206
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• 2016

This paper describes a simple routing control system. We propose achieving high-speed data transmission without modifying the data frame configuration. To add a routing control signal, called the "labeling signal" in this paper, to the data frame, we use a frequency modulation technique on the transmitted frame. This means you need not change the data frame when you transmit additional signals. Using a prototype system comprising a field-programmable gate array and discrete elements, we investigate the system performance and devise a method to achieve high resolution. A three-channel routing control for a 10 Gb/s data frame was achieved, which confirms the advantages of the proposed system.

• Communications for Statistical Applications and Methods
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• 제16권1호
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• pp.1-11
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• 2009

마이크로데이터를 이용자에게 제공하면 레코드 단위의 데이터가 노출되고 응답자의 정보 노출위험이 불가피하다. 통계적 노출조절기법은 통계데이터 제공시 노출위험을 줄이면서 데이터 유용성을 높이기 위한 통계적 기법이다. 본 논문에서는 노출과 노출위험, 그리고 통계적 노출조절기법을 고찰하였고 데이터 유용성과 연관하여 노출조절기법 선택 전략을 살펴보았으며, '위험-유용성 경계 지도' 방법의 예를 알아보았다. 마지막으로 마이크로데이터를 이용자에게 제공할 때 단계별로 검토할 사항을 알아보았다.

• 한국통신학회논문지
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• 제29권9A호
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• pp.1013-1021
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• 2004

WCDMA 방식 이동 멀티미디어 시스댐어써 고속 데이터 λ냉자에 의한 간섭은 시스템의 용량과 성능을 저하 시키는 주요 요인이 되며, 적응형 안테나 시스템을 도입하여 고속 데이터 사용자의 간성을 크게 줄여줌으로써 시스템의 성능을 향상시킬 수 있다 이 경우, 적용형 안테나의 효과를 극대화하기 위한 방법으로서, 호 수락제어 기법의 최적화가 중요하고 생간 핸드요프 과정에 있어서의 효율적인 제어 방식이 중요한 논제가 된다. 본 논문에서 는 핸드요프 되는 고속의 데이터들을 효과적으로 처리하기 위하여 Soft QoS 를 적용한 호 수락 제어 알고리즘을 제안하고, 전송 속도에 따른 적응형 핸드요프 제어 방식을 제안하였다 제안된 알고리듬을 적용함으로써, 적응형 안테나 시스템의 고속 데이터 전송을 효과적으로 수행하연서도 셀 내 저속 가업자의 호 블록킹 확률을 크게 줄일 수 있음을 컴퓨터 시뮬레이션을 통한 비교분석으로 입증하였다.