• Journal of the Korean Institute of Telematics and Electronics
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• v.23 no.5
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• pp.653-657
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• 1986

This paper describes a method to design a guaranteed cost controller for a system with uncertain parameters. The design procedure consists of defining an arbitrary function which satisfies certain condition and minimizing it over the control input. When the method is applied to a class kof linear systems with uncertain parameters, a Riccati equation with additional terms results. A simple example is presented to illustrate the usefulness of this method.

• Journal of Korean Neurosurgical Society
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• v.67 no.4
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• pp.477-482
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• 2024

This report introduces a simple method to visualize the captured thrombus in real-time during suction thrombectomy using "contrast-in-stasis technique". It enables visualization of the thrombus captured by a suction catheter as it is being retrieved through the tortuous course of the carotid artery eventually into the guiding catheter. It also offers visual identification of important findings such as fragmentation of thrombus into pieces or loss of thrombus during retrieval, and, therefore, helps clinicians to make further critical decisions during the procedure.

• Journal of Intelligence and Information Systems
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• v.12 no.2
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• pp.125-144
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• 2006

The development of mobile applications is fast in recent years. However, nearly all applications are for messaging, financial, locating services based on simple interactions with mobile users because of the limited screen size, narrow network bandwidth, and low computing power. Processing an algorithm for supporting a group decision process on mobile devices becomes impossible. In this paper, we introduce the mobile-oriented simple interactive procedure for support a group decision making process. The interactive procedure is developed for multiple objective linear programming problems to help the group select a compromising solution in the mobile Internet environment. Our procedure lessens the burden of group decision makers, which is one of necessary conditions of the mobile environment. Only the partial weak order preferences of variables and objectives from group decision makers are enough for searching the best compromising solution. The methodology is designed to avoid any assumption about the shape or existence of the decision makers' utility function. For the purpose of the experimental study of the procedure, we developed a group decision support system in the mobile Internet environment, MOBIGSS and applied to an allocation problem of investor assets.

• Archives of Plastic Surgery
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• v.35 no.3
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• pp.345-348
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• 2008

Purpose: Fracture of the frontal sinus accounts for 5-15% of all facial fractures. Only anterior table fracture occupies one third of the frontal sinus fracture. Conventional coronal approach is the standard treatment, but this method is very aggressive, especially in patient with simple, depressed, anterior frontal sinus wall fracture. We introduce new, simple technique for these patients, using small incision and Dual-top screws. Methods: A 27-year-old male patient was introduced to our department under the impression of fracture of frontal sinus, involving only anterior table. Under general anesthesia, 1.5 cm-sized, small incision was made on the suprabrow area. We reduced fractured fragment with two dual-top screws and 25G wires. Fixation was not necessary Results: The operation took about forty minutes, and the patient discharged 2 days after the operation. Postoperative 2 months follow up CT shows maintenance of reduction site. Gross depression of the forehead and visible scar was not observed. Conclusion: Although the indication of this procedure is limited, less aggressive, simple and very effective to the patient with simple. depressed, anterior frontal sinus fracture.

• Journal of Korean Foot and Ankle Society
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• v.5 no.1
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• pp.69-73
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• 2001

Purpose: The purpose of this study is to report the result of endoscopic assisted curettage and bone graft for the treatment of simple bone cyst in the calcaneus. Materials and Methods: Three cases in three patients who had curettage and bone graft of simple bone cyst in the calcaneus under endoscopic view were prospectively reviewed. A minimum follow-up of 1 year was required for entrance into the study. The results of treatment were clinically and radiologically assessed. Results: One case with preoperative heel pain gained complete relief of the pain at postoperative four weeks. All three cases had radiological union of grafted bone at an average of thirteen weeks after the operation. Shortened hospitalization and decreased postoperative pain were remarkable. Complications such as infection, skin necrosis, nerve injury, and, fracture were not seen. There was no evidence of the recurrence of the cyst in all three cases. Conclusion: Endoscopic assisted curettage and bone graft of simple bone cyst in the calcaneus is thought as an effective alternative procedure avoiding the possible complications of the classic method.

• Steel and Composite Structures
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• v.25 no.6
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• pp.717-726
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• 2017

In this paper, a new simple shear deformation theory for bending analysis of functionally graded plates is developed. The present theory involves only three unknown and three governing equation as in the classical plate theory, but it is capable of accurately capturing shear deformation effects, instead of five as in the well-known first shear deformation theory and higher-order shear deformation theory. A shear correction factor is, therefore, not required. The material properties of the functionally graded plates are assumed to vary continuously through the thickness, according to a simple power law distribution of the volume fraction of the constituents. Equations of motion are obtained by utilizing the principle of virtual displacements and solved via Navier's procedure. The elastic foundation is modeled as two parameter elastic foundation. The results are verified with the known results in the literature. The influences played by transversal shear deformation, plate aspect ratio, side-to-thickness ratio, elastic foundation, and volume fraction distributions are studied. Verification studies show that the proposed theory is not only accurate and simple in solving the bending behaviour of functionally graded plates, but also comparable with the other higher-order shear deformation theories which contain more number of unknowns.

• Journal of KIISE:Software and Applications
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• v.33 no.4
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• pp.427-439
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• 2006

The SBF (Simple Boundary Follower) is a boundary-following algorithm, and is used mainly for image recognition and presentation. The SBF is very popular because of its simplicity and efficiency in tracing the boundary of an object from an acquired binary image; however, it does have two drawbacks. First, the SBF cannot consistently process inner or inner-outer corners according to the follower's position and direction. Second, the SBF requires movement operations for the non-boundary pixels that are connected to boundary pixels. The MSBF (Modified Simple Boundary Follower) has a diagonal detour step for preventing inner-outer corner inconsistency, but is still inconsistent with inner-corners and still requires extra movement operations on non-boundary pixels. In this paper, we propose the ISBF (Improved Simple Boundary Follower), which solves the inconsistencies and reduces the extra operations. In addition, we have classified the tour maps by paths from a current boundary pixel to the next boundary pixel and have analyzed SBF, MSBF, and ISBF. We have determined that the ISBF has no inconsistency issues and reduces the overall number of operations.

• Geotechnical Engineering
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• v.14 no.3
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• pp.95-108
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• 1998

Downhole testing and seismic CPT (SCPT) have been widely used to evaluate stiffness profiles of the subgrade. Advantages of downhole testing and SCPT such as low cost, easy operation and a simple seismic source have got these testings more frequently adopted in site investigation. For the automated analysis of downhole testing and SCPT, the concept of interval measurements has been practiced. In this paper. a new inversion procedure to deal tilth the interval measurements for the automated downhole testing and SCPT (including a newlydeveloped continuous SCPT) is proposed. The forward modeling in the new inversion procedure incorporates ray path theory based on Snell's law. The formulation for the inversion analysis is derived from the maximum likelihood approach, which estimates the maximum likelihood of obtaining a particular travel time from a source to a receiver. Verification of the new inversion procedure was performed with numerical simulations of SCPT using synthesized profiles. The results of the inversion analyses performed for the synthetic data show that the new inversion analysis is a valid procedure which enhances Va profiles determined by downhole testing and SCPT.

• The Korean Journal of Pain
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• v.30 no.3
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• pp.220-228
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• 2017

Background: The transforaminal (TF) epidural steroid injection (ESI) is suggested as more effective than the interlaminar (IL) route due to higher delivery of medication at the anterior epidural space. However, serious complications such as spinal cord injury and permanent neural injury have been reported. The purpose of this study is to evaluate and compare the clinical effectiveness, technical ease, and safety of the TF and parasagittal IL (PIL) ESI. Methods: A total of 72 patients were randomized to either the PIL group (n = 41) or the TF group (n = 31) under fluoroscopic guidance. Patients were evaluated for effective pain relief by the numerical rating scale (NRS) and Oswestry Disability Index (ODI) (%) before and 2 weeks after the ESI. The presence of concordant paresthesia, anterior epidural spread, total procedure time, and exposed radiation dose were also evaluated. Results: Both the PIL and TF approach produced similar clinically significant improvements in pain and level of disability. Among the 72 patients, 27 PIL (66%) and 20 TF (64%) patients showed concordant paresthesia while 14 (34%) and 11 (36%) patients in the same respective order showed disconcordant or no paresthesia. Radiation dose and total procedure time required were compared; the PIL group showed a significantly lower radiation dose ($30.2{\pm}12$ vs. $80.8{\pm}26.8$ [$Cgy/cm^2$]) and shorter procedure time ($96.2{\pm}31$ vs. $141.6{\pm}30$ seconds). Conclusions: ESI under fluoroscopic guidance with PIL or TF approach were effective in reducing the NRS and ODI. PIL ESI was a technically easier and simple method compared to TF ESI.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.3A
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• pp.180-187
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• 2002

The decoding method using covering polynomials is an extended form of error-trapping decoding, and is a simple and effective means to implement decoders for cyclic codes. Covering polynomials can be used for soft-decision decoding as well as for decoding beyond the bounded distance of the code. The implementation complexity is proportional to the number of covering polynomials employed. In this paper, the soft-decision decoding procedure using covering polynomials is described, and the procedure is applied to the [23,12] Golay code. A new set of covering polynomials is derived for the procedure, which is presented as a generalized closed-form solution. The set can be efficiently utilized for decoding a class of cyclic codes including the Golay code. Computer simulation of the described procedure is performed to show the trade-offs between the decoder performance and complexity. It is demonstrated that soft-decision decoding of the Golay code using the derived set of covering polynomials has less than 0.2dB deviation from the optimal performance of maximum-likelihood decoding, with a reduced complexity when compared to the Chase Algorithm 2 combined with hard-decision decoding that has nearly identical performance.