• Transactions on Control, Automation and Systems Engineering
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• v.3 no.3
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• pp.146-151
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• 2001

Optical disk drive has excellent advantage of random accessibility of which performance is measured by access time. However, due to the increased rotational velocity of the disk and constraints of mechanical structure, two-stage seek algorithm which executes coarse and fine seeks sequentially has been adopted in most commercial optical disk drives. Although the laser spot is moved to a target track by a single seek operation, the limited operation range of the fine actuator restricts the application of the fine seek algorithm below a few hundreds of tracks. Especially, excessive movement of the objective lens causes a failure in generation of track-cross pulse and results in an unstable seek operation. In this paper, a new control algorithm for extending the fine seek range is proposed with an appropriate control structure. The coarse actuator is utilized to reduce the misalignment between the objective lens and the laser beam axis, and the fine actuator is controlled to follow the reference velocity trajectory. The proposed algorithm is applied to a CD-ROM drive to show its feasibility and some experimental results are presented.

• Journal of Biosystems Engineering
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• v.43 no.4
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• pp.440-444
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• 2018

Purpose: Cloud-computing technology has several advantages, including maintenance, management, accessibility, and computing power. A greenhouse-control system utilizing these advantages was developed using a private cloud-computing system. Methods: A private cloud needs a collection of servers and a suite of software tools to monitor and control cloud-computing resources. In this study, a server farm, operated by OpenStack as a cloud platform, was constructed using servers, and other network devices. Results: The greenhouse-control system was developed according to the fundamental cloud service models: infrastructure as a service, platform as a service, and software as a service. This system has four additional advantages - security, control function, public data use, and data exchange. There are several considerations that must be addressed, such as service level agreement, data ownership, security, and the differences between users. Conclusions: When the advantages are utilized and the considerations are addressed, cloud-computing technology will be beneficial for agricultural use.

• Journal of Korean Society of Transportation
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• v.28 no.6
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• pp.55-62
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• 2010

The purpose of this research is to provide an a basic data for setting design standards and proposing improvement for public open space by analysis one which is the factor that quite influences public open space by factor analysis. First, Extract main design factors by survey and field investigation of the Public Open Space of Centum and Seomyeon in Pusan. After the extraction, Control and simulation of main design factors which selected by survey for making better improved public open space and resolving problems of it. Based on simulation data, the five-factors drawed by psychological estimation and factor analysis are Accessibility, Intimacy, Openness, Amenity, Convenience. By use of a result, Multiple Regression Analysis is implemented for correlation analysis between five-factors and user's satisfaction in the public open space. Therefore the it which influenced user's satisfaction in the public open space most was Accessibility. So, the public open space must be designed to improve Accessibility and Intimacy, Openness, Amenity, Convenience which influenced user's satisfaction were reviewed primary.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.10 no.2
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• pp.135-141
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• 2010

This research examines technologies and systems regarding right to control information in the network era. For this purpose, It attempts an integrated analysis of technologies and systems on the basis of the tree components of cyberspace. And it examines the prior researches and cases on privacy, personal information, and right to control information with emphasis on technologies and systems of the cyberspace. To protect privacy information, it analyses vulnerability of element technology, platform service technology, and individual technology. In particular, it describes, from the perspective of right to control information, the risk and security measures for personal information to be used as relation-context in the Web 2.0 environment. The research result will assist the methodology of future researches for grand theory on privacy information and help understanding the interaction between technology and society.

• Journal of The Institute of Information and Telecommunication Facilities Engineering
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• v.10 no.1
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• pp.7-13
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• 2011

Matrix multiplication is a fundamental operation of linear algebra and arises in many areas of science and engineering. This paper introduces an efficient parallel matrix multiplication scheme on N ${\times}$ N mesh-connected SIMD array processor, called multiple hierarchical SIMD architecture (HMSA). The architectural characteristic of HMSA is the hierarchically structured control units which consist of a global control unit, N local control units configured diagonally, and $N^2$ processing elements (PEs) arranged in an N ${\times}$ N array. PEs are communicating through local buses connecting four adjacent neighbor PEs in mesh-torus networks and global buses running across the rows and columns called horizontal buses and vertical buses, respectively. This architecture enables HMSA to have the features of diagonally indexed concurrent broadcast and the accessibility to either rows (row control mode) or columns (column control mode) of 2D array PEs alternately. An algorithmic mapping method is used for performance evaluation by mapping matrix multiplication on the proposed architecture. The asymptotic time complexities of them are evaluated and the result shows that paralle matrix multiplication on HMSA can provide significant performance improvement.

• Journal of Institute of Control, Robotics and Systems
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• v.15 no.7
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• pp.688-693
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• 2009

In terms of water meter reading, the majority of 16 million houses use mechanical water meter in korea. So, a member of the utility's staff needs to access periodically the water meter and the value of the metered volume. However, due to the use of mechanical water meter, many issues have been appeared as cost, time, errors, accessibility, and readability. To settle these issues, we developed the walk-by meter reading system of digital water meter and outside indicator based on ubiquitous. And we could get the characteristics and the economical efficiency for water meter reading system. Thus, this study shows that the system can be widely used to the block system and the meter reading system for stable water supply.

• Journal of the Korean Society of Marine Environment & Safety
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• v.21 no.3
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• pp.309-314
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• 2015

A sunken ship often involves an oil spill. This paper was carried out to minimize environmental and cost damages stemming from oil spil of sunken shipl. Through the analysis of both the standards of the oil tank system and installation, we have identified potential oil spill sites and proposed a remedy of prevention. The result of study, the air pipes of the oil tank are a vulnerable point for oil spill. Also, the remote control devices of emergency shut-off valve have poor accessibility at abandon ship, making it difficult to shut off the emergency shut-off valve. Thus, we propose the addition of a remote quick closing valve in the air pipe and the building of a central control system.

• Journal of the Korea Computer Industry Society
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• v.2 no.10
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• pp.1355-1364
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• 2001

Internal control comprises the plan of Organization and all of the coordinate methods and measure adopted within a business to safeguard its assets. check the accuracy and reliability of its accounting data, promote operation efficiency, and encourage adherence to prescribed managerial policies. Internal accounting control is classified into General Control and Application Control. Essential elements of internal accounting control as follows : 1. General Control $\circled1$ Organization and operation controls. $\circled2$ System development and Documentation controls. $\circled3$ Hardware controls. $\circled4$ Software and hardware Accessibility controls. $\circled5$ General systems security and protection 2. Application control $\circled1$Input control. $\circled2$ Processing control. $\circled3$ Output control. Internal accounting control can establish a total management information system by connecting with mana-gement control of a company, and enable decision makers to establish decision support system(DSS), is so vital today.

• Korean Journal of Social Welfare
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• v.58 no.1
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• pp.237-264
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• 2006

The purpose of this study is to examine the level of social integration of the person with physical disabilities based on independent living paradigm according to life span and to find factors affecting social integration and therefore to make policy implications for a better rehabilitation system. The data was obtained through telephone interviews with physically disabled residing in the city of Seoul and the suburb area of the city. The final sample consists of 591 respondents. The data was analyzed through frequency, oneway anova, pearson's correlation analysis, and multiple regression. In this study, social integration based on independent living paradigm was divided into separate but related dimensions: autonomy of activity daily living, accessibility, economic level, degree of social support satisfaction, consumer control, psychological empowerment. The major findings of this study were as follows: First, the levels of six dimensions of social integration based on independent living paradigm were very different and especially the level of dimensions such as degree of social support satisfaction and consumer control were lower than other dimensions of social integration. Second, each level of social integration by life span was very different. Finally, the factors affecting social integration were socio-psychological traits such as social support, rehabilitation services, self esteem and acceptance of disability as well as the attribution to disability. The current findings suggest that improving nay only ADL or accessibility but also consumer control or social support should be considered by professional and policy makers. And differentiated intervention and policy according to life span necessary to policy makers and field practitioners.

• International Journal of Control, Automation, and Systems
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• v.6 no.2
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• pp.186-193
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• 2008

The Internet's low cost and ubiquity present an attractive option for real-time distributed control of processes on the factory floor. When integrated with the Internet, the LonWorks open control network can give ubiquitous accessibility with the distributed control nature of information on the factory floor. One of the most important points in real-time distributed control of processes is timely response. There are many processes on the factory floor that require timely response. However, the uncertain time delay inherent in the network makes it difficult to guarantee timely response in many cases. Especially, the transmission characteristics of the LonWorks/IP network show a highly stochastic nature. Therefore, the time delay problem has to be resolved to achieve high performance and quality of the real-time distributed control of the process in the LonWorks/IP Virtual Device Network (VDN). It should be properly predicted and compensated. In this paper, a new distributed control scheme that can compensate for the effects of the time delay in the network is proposed. It is based on the PID controller augmented with the Smith predictor and disturbance observer. Designing methods for output feedback filter and disturbance observer are also proposed. Tracking position control experiment of a geared DC Servo motor is performed using the proposed control method. The performance of the proposed controller is compared with that of the Internal Model Controller (IMC) with the Smith predictor. The result shows that the performance is improved and guaranteed by augmenting a PID controller with both the Smith predictor and disturbance observer under the stochastic time delay in the LonWorks/IP VDN.