• Proceedings of the KIPE Conference
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• 2000.07a
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• pp.480-484
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• 2000

The pole placement technique for control design of the current mode controlled DC-DC switchmode power converter is proposed. It is compared with conventional transfer function analysis. Using the pole placement technique control design automation algorithm, by computer-based tool is presented. Control design example with large signal simulation is shown.

• The Korean Journal of Pain
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• v.3 no.1
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• pp.59-62
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• 1990

Epidural block is used for surgical analgesia, postoperative pain management, obstetric relief and management of chronic pain. Long-term pain control for chronic pain is achieved by development of epidural catheter placement technic. But long term placement of epidural catheteter has several problems, epidural hematoma, epidural absess and neural damage. We had successfully managed long-term placement of epidural catheter in patient with diabetic neuropathy who was susceptable to infection. The duration of epidural catheter placement was 416 days and specific complication was not occurred.

• Journal of the Korean Institute of Telematics and Electronics
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• v.26 no.10
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• pp.1598-1605
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• 1989

This paper describes an efficient global cell (module) placement strategy called HALO (Hierarchical Alternating Linear Ordering)which generates global 2-D placement of circuit modules by hierarchical application of linear ordering in alternating direction. We tried, in principle, to explain why HALO should perform better than other typical, somehat successful, analytical approaches such as min-cut, force-directed relaxation(FDR)or its likes. We have implemented HALO as a program for standard cell placement. Experimental results on two benchmark circuits, primary and primary 2 consisting of 752 and 2907 cells, respectively have shown a decrease of half-perimeter routing length by 7% and 24%, respectively compared to the best available results obtained so far. Total CPU time including the following detailed placement was less than half of the earlier work.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2004.10a
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• pp.241-245
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• 2004

Among the various manufacturing processes of composites, the tape lay-up process of thermoset prepreg has many advantages compared to autoclave or hot press forming. It has a high potential to process automation and continuous fabrication .. Fiber placement developed as a logical combination of filament winding and automated tape placement to overcome some of the limitations of each manufacturing method. Fiber placement uses a compaction device to apply direct contact between the incoming materials in the fiber placement head and Heat is added to the materials at the nip point of the compaction roller. This paper will discuss property of thermoset composite as compaction and heat effect in Automated fiber placement

• Smart Structures and Systems
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• v.4 no.4
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• pp.465-492
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• 2008

Proper pretest planning is a vital component of any successful vibration test on engineering structures. The most important issue in dynamic testing of many engineering structures is arriving at the number and optimal placement of sensors. The sensors must be placed on the structure in such a way that all the important dynamic behaviour of a structural system is captured during the course of the test with sufficient accuracy so that the information can be effectively utilised for structural parameter identification or health monitoring. Several optimal sensor placement (OSP) techniques are proposed in the literature and each of these methods have been evaluated with respect to a specific problem encountered in various engineering disciplines like aerospace, civil, mechanical engineering, etc. In the present work, we propose to perform a detailed characteristic evaluation of some selective popular OSP techniques with respect to their application to practical civil engineering problems. Numerical experiments carried out in the paper on various practical civil engineering structures indicate that effective independence (EFI) method is more consistent when compared to all other sensor placement techniques.

• Journal of the Korean Institute of Telematics and Electronics
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• v.24 no.6
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• pp.1049-1055
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• 1987

This paper describes a near-optimal standard cell layout strategy which consists of three consecutives steps` partition, placement, and routing. In the partition step, a given network is torn apart into many subnetworks such that each subnetworks contains as many cells as possible with minimum interocnnections between subnetwork. In the placement step, the conventional string placement algorithm was modified. Also, bonding pads were placed such that their connections to the related cells are shortest. As a result for the tested example, the placement time was saved by 60% and the total routing lengths were saved by more than 20% and substantial improvements in the number of feed-through cell and the track density were obtained. The layout program is coded in PASCAL and implemented on a VAX 11-750/UNIX computer.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.41 no.3
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• pp.311-319
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• 1992

In this paper, a direct adaptive pole placement controller for an unknown linear time-invariant single-input single-output nonminimum phase plant is proposed. To design this direct adaptive pole placement controller, the auxiliary signals are introduced. Consequently, a linear equation error model is formulated for estimating both the controller parameters and the additional auxiliary parameters. To estimate the controller parameters and the additional auxiliary parameters, the exponentially weighted least-squares algorithm is implemented, and a method of selecting the characteristic polynomials of the sensitivity function filters is proposed. In this method, all the past measurement data are weighted exponentially. A series of simulations for a nonminimum phase plant is presented to illustrate some features of both the parameter estimation and the output response of this adaptive pole placement controller.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.9
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• pp.3539-3558
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• 2015

This paper investigates and analyzes the default block placement strategy of HDFS. HDFS is a typical representative distributed file system to stream vast amount of data effectively at high bandwidth to user applications. However, the default HDFS block placement policy assumes that all nodes in the cluster are homogeneous, and places blocks with a simple RoundRobin strategy without considering any nodes' resource characteristics, which decreases self-adaptability of the system. The primary contribution of this paper is the proposition of a network load sensitive block placement strategy. We have implemented our algorithm and justify it through extensive simulations and comparison with similar existing studies. The results indicate that our work not only performs much better in the data distribution but also improves write performance more significantly than the others.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1997.04a
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• pp.308-315
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• 1997

In this study, the effect of modal filter error on the vibration control characteristics of flexible structures is analyzed for IMSC(Independent Modal Space Control), and optimal sensor placement in the structural vibration control with consideration of performance of modal filter has been studied. An Lyapunov asymptotic stability condition has been derived, which depends on the magnitude of the modal filter errors. The extent of the response deviation of the closed-loop system is also derived and evaluated using operator techniques. A sensor placement technique has also been suggested to maximize the performance of the modal filter. It has been found by a series of simulation that the suggested sensor placement technique is very effective on the determination of the number and placement of sensors of modal filter in the structural vibration control.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.5
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• pp.1998-2014
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• 2016

In recent years, cloud computing services based on smart phones and other mobile terminals have been a rapid development. Cloud computing has the advantages of mass storage capacity and high-speed computing power, and it can meet the needs of different types of users, and under the background, mobile cloud computing (MCC) is now booming. In this paper, we have put forward a new classification-based virtual machine placement (CBVMP) algorithm for MCC, and it aims at improving the efficiency of virtual machine (VM) allocation and the disequilibrium utilization of underlying physical resources in large cloud data center. By simulation experiments based on CloudSim cloud platform, the experimental results show that the new algorithm can improve the efficiency of the VM placement and the utilization rate of underlying physical resources.