• Journal of Korean Neurosurgical Society
• /
• v.40 no.1
• /
• pp.6-10
• /
• 2006

Objective : The purpose of this study is to evaluate the surgical outcomes of bifrontal interhemispheric[BIH] approach and compare them to those of the pterional approach for the treatment of craniopharyngioma. Methods : Seventeen patients had their first operation for the resection of craniopharyngiomas between 2000 and 2004 at our medical center. Eleven patients who had the pterional approach and 6 with the BIH approach were enrolled. The age range at the time of surgery was 5 to 80 years [mean age 35.6 years old]. The presenting symptoms were visual disturbance increased intracranial pressure in 5 patients. Results : The tumors were totally removed in 3 [27 %] and subtotally in 8 [73 %] patients with the pterional approach. Total tumor removal was achieved in 5 out of 6 [83%] patients by the BIH approach, except improved in 4 [36 %] patients treated with the pterional approach and in all patients treated by the BIH approach. Conclusion : The BIH approach for craniopharyngioma surgery may be an effective and safe approach for tumors that extend outside of the sellar-suprasellar region with acceptable outcomes.

• Journal of KIISE:Databases
• /
• v.30 no.4
• /
• pp.372-380
• /
• 2003

Temporal databases support time-varying events so that conventional aggregate functions are extended to be processed with time for temporal aggregate functions. In the previous approach, it is done repeatedly to find time intervals and is calculated the result of each interval whenever target events are different. This paper proposes a method which processes temporal aggregate function queries using time point sequence. We can make time point sequence storing the start time and the end time of events in temporal databases in advance. It is also needed to update time point sequence due to insertion or deletion of events in temporal databases. Because time point sequence maintains the information of time intervals, it is more efficient than the previous approach when temporal aggregate function queries are continuously requested, which have different target events.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.34 no.8
• /
• pp.989-996
• /
• 2010

Statistical regression and/or interpolation models have been used for data analysis and response prediction using the results of the physical experiments and/or computer simulations in structural engineering fields. These models have been employed during the last decade to develop a variety of design methodologies. However, these models only handled responses with respect to space variables such as size and shape of structures and cannot handle time-variant dynamic responses, i.e. response varying with time. In this research, statistical space-time metamodels based on multiple response approach that can handle responses with respect to both space variables and a time variable are proposed. Regression and interpolation models such as the response surface model (RSM) and kriging model were developed for handling time-variant dynamic responses of structural engineering. We evaluate the accuracies of the responses predicted by the two statistical space-time metamodels by comparing them with the responses obtained by the physical experiments and/or computer simulations.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2016.05a
• /
• pp.727-730
• /
• 2016

TSC means classifying time series data based on pattern. Time series data is quite common data type and it has high potential in many fields, so data mining and machine learning have paid attention for long time. In traditional approach, distance and dictionary based methods are quite popular. but due to time scale and random noise problems, it has clear limitation. In this paper, we propose a novel approach to deal with these problems with CNN and data mutation. CNN is regarded as proven neural network model in image recognition, and could be applied to time series pattern recognition by extracting pattern. Data mutation is a way to generate mutated data with different methods to make CNN more robust and solid. The proposed method shows better performance than traditional approach.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.14 no.6
• /
• pp.57-62
• /
• 2015

A large variety of pipe flanges are required in the marine and construction industry. Pipe flanges are usually welded or screwed to the pipe end and are connected with bolts. This approach is very simple and has been widely used for a long time; however, it results in high development costs and low productivity, and the products made through this approach usually have safety problems in the welding area. In this research, a new approach for forming pipe flanges based on cold forging and the floating die concept is presented. This innovative approach increases the effectiveness of the material usage and saves time and costs compared with the conventional welding method. To ensure the dimensional accuracy of the final product, finite element analysis (FEA) was carried out to simulate the process of cold forging, and orthogonal experiment methods were used to investigate the influence of four manufacturing factors (stroke of distance, pin die angle, forming of pipe diameter, and speed of the die) and predict the best combination of them. The manufacturing factors were obtained through numerical and experimental studies, which show that the approach is very useful and effective for the forming of pipe flanges and could be widely used in the future.

• Journal of Family Resource Management and Policy Review
• /
• v.14 no.3
• /
• pp.15-36
• /
• 2010

The purpose of this study is to review previous domestic and foreign studies and to investigate personal work-life harmonization through theoretical research on familyfriendly management using a dual agenda approach. The authors briefly identified trends and critically reviewed domestic researches on family-friendly management and foreign studies of scholars that overcame the limitations of domestic studies to present a foundation for work-life harmonization through a dual agenda approach. As a result, the existing family-friendly management was found to be compatible with work and family but was not effective in developing personal careers. The workers who actively accepted family-friendly management as part of their work-life balance were mostly female laborers who were employed part-time, had lower academic education, earned lower wages and, in general, were non-professional workers without specific skills or career aspirations. The remainder of the workers, full-time male employees, with higher education and with professional knowledge and skills, inevitably worked longer, more labor-intensive hours, due to the advent of the dual agenda approach. A new work-life harmonization program is urgently needed not only for family-friendliness but also for healthy organizations, individual career development and personal wellbeing.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.12 no.8
• /
• pp.1377-1383
• /
• 2008

Parameterization of a 3D triangular mesh is a fundamental problem in various applications of geometric modeling and computer graphics. There are two major paradigms in mesh parameterization: energy functional minimization and the convex combination approach. In general, the convex combination approach is wifely used because of simple concept and one-to-one mapping. However, the approach has some problems such as high distortion near the boundary and time complexity. Moreover, the stability of the linear system may not be preserved according to the geometric information of the mesh. In this paper, we present an extension of the convex combination approach based on the mean value coordinates, which resolves the drawbacks of the convex combination approach. This may be a more practical solution because it is able to generate a stable linear system in a short time.

• Structural Engineering and Mechanics
• /
• v.7 no.2
• /
• pp.127-145
• /
• 1999

This paper deals with the development of an approach for evaluating the squash load and rigidity of unprotected concrete filled steel columns at elevated temperatures. The current approach of evaluating these properties is reviewed. It is shown that with a non-uniform temperature distribution, over the composite cross-section, the calculations for the squash load and rigidity are tedious in the current method. A simplified approach is proposed to evaluate the temperature distribution, squash load, and rigidity of composite columns. This approach is based on the model in Eurocode 4 and can conveniently be used to calculate the resistance to axial compression of a concrete filled steel column for any fire resistance time. The accuracy of the proposed approach is assessed by comparing the predicted strengths against the results of fire tests on concrete filled circular and square steel columns. The applicability of the proposed approach to a design situation is illustrated through a numerical example.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
• /
• v.25 no.2
• /
• pp.90-95
• /
• 2014

Background and Objectives : Arytenoid adduction procedure is one of the main surgical options addressed for the correction of glottal incompetence in patients with unilateral vocal cord paralysis. Traditionally, a midline approach is used for identifying and suturing around the muscular process, which often needs over-traction of the thyroid cartilage and results in patient's discomfort as well as surgeon's distress. The authors investigated the advantage of a modified procedure, lateral approach, in which the arytenoid cartilage is exposed through the space between strap muscles and sternocleidomastoid muscle. Materials and Methods : Retrospective chart review was performed for 66 patients who received arytenoid adduction surgery at Samsung Medical Center, between the year 1997 and 2014. Operation time, types of anesthesia, voice outcomes and complications were compared between the midline (n=22) and the lateral (n=44) approach group. Results : Operation time was shorter in the lateral approach group ($125{\pm}24min$) than in the midline group ($144{\pm}24min$). Arytenoid adduction was proceeded under local anesthesia in 66% (n=29/44) and 14% (n=3/22) of patients with lateral and midline approach group, respectively. Voice outcomes and complication rates were comparable between the two groups. Injection laryngoplasty in conjunction with arytenoid adduction resulted in more favorable voice outcomes. Conclusion : A lateral approach for the arytenoid adduction procedure showed comparable voice outcomes and similar complication rates with those of a midline approach. However, lateral approach provided less discomfort to the patients and less distress to a surgeon, and therefore, shorter operation time was needed and local anesthesia could be more frequently applied for this modified procedure.

• Proceedings of the Korean Institute of Intelligent Systems Conference
• /
• 2005.11a
• /
• pp.95-98
• /
• 2005

This paper presents intelligent digital redesign method of global approach for hybrid state space fuzzy-model-based controllers. For effectiveness and stabilization of continuous-time uncertain nonlinear systems under discrete-time controller, Takagi-Sugeno(TS) fuzzy model is used to represent the complex system. And global approach design problems viewed as a convex optimization problem that we minimize the error of the norm bounds between nonlinearly interpolated linear operators to be matched. Also by using the power series, we analyzed nonlinear system's uncertain parts more precisely. When a sampling period is sufficiently small, the conversion of a continuous-time structured uncertain nonlinear system to an equivalent discrete -time system have proper reason. Sufficiently conditions for the global state -matching of the digitally controlled system are formulated in terms of linear matrix inequalities (LMls). Finally, we prove the effectiveness and stabilization of the proposed intelligent digital redesign method by applying the chaotic Lorentz system.