• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.12
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• pp.2366-2373
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• 2007

In this paper, a low-power and small-area asynchronous 1 kilobit EEPROM for passive UHF RFID tag chips is designed with $0.18{\mu}m$ EEPROM cells. As small area solutions, command and address buffers are removed since we design asynchronous I/O interface and data output buffer is also removed by using separate I/O. To supply stably high voltages VPP and VPPL used in the cell array from low voltage VDD, Dickson charge pump is designed with schottky diodes instead of a PN junction diodes. On that account, we can decrease the number of stages of the charge pump, which can decrease layout area of charge pump. As a low-power solution, we can reduce write current by using the proposed VPPL power switching circuit which selects each needed voltage at either program or write mode. A test chip of asynchronous 1 kilobit EEPROM is fabricated, and its layout area is $554.8{\times}306.9{\mu}m2$., 11% smaller than its synchronous counterpart.

• Journal of Communications and Networks
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• v.11 no.2
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• pp.166-174
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• 2009

In this paper, a distributed power and end-to-end rate control algorithm is proposed in the presence of licensed users. By Lagrangian duality theory, the optimal power and rate control solution is given for the unlicensed users while satisfying the interference temperature limits to licensed users. It is obtained that transmitting with either 0 or the maximum node power is the optimal scheme. The synchronous and asynchronous distributed algorithms are proposed to be implemented at the nodes and links. The convergence of the proposed algorithms are proved. Finally, further discussion on the utility-based fairness is provided for the proposed algorithms. Numerical results show that the proposed algorithm can limit the interference to licensed user under a predefined threshold.

• Korean Journal of Computational Design and Engineering
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• v.9 no.4
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• pp.361-372
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• 2004

Collaborative and distributed engineering web services are emerging as a viable alternative to the traditional design and engineering process automation. Existing approaches have limitations in supporting long-running engineering transactions, automatic engineering process orchestration and choreography, synchronous and asynchronous conversation, and geometric abstraction for transmission and sharing. In this paper, we present a process-centric engineering web service methodology to overcome these limitations by utilizing BPEL-based (Business Process Execution Language) process templates and coordination broker-based conversation support. This paper discusses the synchronization of engineering web services which can be either peer-centric or process-centric to support long-running engineering transactions and conversation. The process orchestration and choreography broker works as a service dispatching and aggregation mediator for executing process templates, which enables the individual activity or the engineering process to dynamically select and invoke one of the alternative web services through the run-time process brokering. Further, the paper presents how to support collaboration over the running process using conversation policy.

• Journal of Korea Spatial Information System Society
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• v.11 no.2
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• pp.111-118
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• 2009

Recently many global enterprises build RTLS system for their environments. RTLS is used to detect object at real tim e. Unlike RFID, RTLS tags are read automatically and continuously, independent of the process that moves the tags. The proposed functionality of standard API has two problems. When middleware provides data to application, it sends a huge amount of data that may be useless. When only an application requests for data, the middleware replies result data in synchronous mode. This paper proposes a method to reduce an amount of data transferring from middleware to application and an addition communication mode to support real-time event processing in the middleware. Also, we designed and implemented an RTLS middleware applying the proposed methods.

• Journal of Korea Society of Industrial Information Systems
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• v.4 no.4
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• pp.60-70
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• 1999

Internet based on web service is growing rapidly and the effort to standardize the next generation web is wold-widely being made. When the web was developed for the first time, HTTP, HTML, and URL were designed based on the structure of text background. Through those asynchronous search and simple unified expression patterns have been used But recently many data on internet me becoming complicated Consequently new structure and expression patterns including synchronous multimedia information are requested The currently used standard language among user interface domain of W3C is SMIL which is XML-based one SMIL describes where and how long the multimedia factors are integrated on the web. In this paper the standardization trend and important issues related to SMIL are reviewed and analysed Also the development of technology is discussed.

• Journal of Korea Society of Industrial Information Systems
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• v.6 no.3
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• pp.1-19
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• 2001

Internet based on web service is growing rapidly and the effort to standardize the next generation web is world-widely being made. When the web was developed for the first time, HTTP, HTML, and URL were designed based on the structure of text background. Through those, asynchronous search and simple, unified expression patterns have been used. But recently many data on internet are becoming complicated. Consequently new structure and expression patterns including synchronous multimedia information are requested. The currently used standard language among user interface domain of W3C is SMIL which is XML-based one. SMIL describes where and how long the multimedia factors are integrated on the web. In this paper the standardization trend and important issues related to SMIL are reviewed and analyzed. Also the development of technology is discussed.

• Journal of the Korea Society of Computer and Information
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• v.9 no.2
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• pp.33-40
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• 2004

According as client/server is generalized by development of computer performance and information communication technology, Servers uses local cache for extensibility and early response time, and reduction of limited bandwidth. Consistency of cached data need between server and client this time and much technique are proposed according to this. This Paper improved update frequency cache consistency in old. Existent consistency techniques is disadvantage that response time is late because synchronous declaration or abort step increases because delaying write intention declaration. Techniques that is proposed in this paper did to perform referring update time about object that page request or when complete update operation happens to solve these problem. Therefore, have advantage that response is fast because could run write intention declaration or update by sel_mode electively asynchronously when update operation consists and abort step decreases and clearer selection.

• The Transactions of the Korea Information Processing Society
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• v.7 no.8
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• pp.2430-2441
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• 2000

A visual concurrent programming environment, called ESTGVP is designed and implemented, which is easy to understand, highly portable, and can represent parallel behaviors. For our purpose, a conventional state transition graph is extended so as to enable both of synchronous and asynchronous parallel operations. We call it extended state transition graph (ESTG). ESTGVP uses the ESTG and texts for programming, and makes it easy programming sequential and parallel behaviors. Also, it is easy to understand the control structure of a program because ESTGVP is a visual programming environment based on the graph. ESTGVP is written in Tel language and thus it is highly portable on various operating systems. It consists of three major components; edition, transformation and execution. If necessary, ESTG can be transformed into C or Tel language, and its execution is based on Tel.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.3
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• pp.174-181
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• 2012

The spindle unit is a core part in high precision machine tool. Rotation accuracy of spindle unit is needed for high dignity cutting and improving the performance of machine tool. However, there are many factors to effect to rotational error motion(rotation accuracy). This study studied how rotational error motion is variation when unbalance amount is variation. Rotation accuracy of initial spindle unit is decided depending on parts and assembly such as bearing. When it is rotation, vibration and noise is appeared depending on volume of unbalance amount, so it works to decrease unbalance amount. The purpose of the study tests that unbalance amount how much effects to initial rotation condition. The result of the study shows that accuracy of parts and assembly is highly necessary to reach high rotation accuracy and unbalance amount hardly effects to initial rotation accuracy. However, it shorten spindle's life because vibration and noise is increasing by increasing unbalance amount and we can expect situation that rotation accuracy is falling by long time operation.

• Korean Journal of Computational Design and Engineering
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• v.20 no.4
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• pp.337-347
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• 2015

This paper presents a dynamic association and natural interaction method for multi-displays composed of smart devices. Users can intuitively associate relations among smart devices by shake gestures, flexibly modify the layout of the display by tilt gestures, and naturally interact with the multi-display by multi-touch interactions. First of all, users shake their smart devices to create and bind a group for a multi-display with a matrix configuration in an ad-hoc and collaborative situation. After the creation of the group, if needed, their display layout can be flexibly changed by tilt gestures that move the tilted device to the nearest vacant cell in the matrix configuration. During the tilt gestures, the system automatically modifies the relation, view, and configuration of the multi-display. Finally, users can interact with the multi-display through multi-touch interactions just as they interact with a single large display. Furthermore, depending on the context or role, synchronous or asynchronous mode is available to them for providing a split view or another UI. We will show the effectiveness and advantages of the proposed approach by demonstrating implementation results and evaluating the method by the usability study.