• Communications for Statistical Applications and Methods
• /
• v.16 no.5
• /
• pp.781-790
• /
• 2009

This paper deals with a rank transformation method and a Theil's method based on an ${\alpha}$-level set of a fuzzy number to construct a fuzzy linear regression model. The rank transformation method is a simple procedure where the data are merely replaced with their corresponding ranks, and the Theil's method uses the median of all estimates of the parameter calculated from selected pairs of observations. We also consider two numerical examples to evaluate effectiveness of the fuzzy regression model using the proposed method and of another fuzzy regression model using the least square method.

• Physical Therapy Korea
• /
• v.6 no.3
• /
• pp.110-120
• /
• 1999

Lymphedema, regardless of etiology, is essentially incurable but different treatment approaches which serve to contain swelling exist. The objectives of treatment are to reduce swelling, restore shape, educate about the self-maintenance methods, and prevent inflammatory episodes, eg, recurrent cellulitis. The purpose of this report is to provide therapists and other medical staff with a general guideline through the example treatment procedure of two patients with lymphedema admitted to Samsung Medical Center. This study demonstrates the effects of the various treatments used and how they helped to achieve improvement in mobility and reduction in swelling of the lower limbs. The basic conservative treatments were sequential intermittent pneumatic pumps, elevation, and CDP (complex decongestive physiotherapy). The surgical procedures (Homan's operation) were carried out after maximal volume reduction through conservative programs. In these cases, we can see greater than 50% reduction in the lymphedema in those treated by conservative and surgical procedures. This presents a simple, reliable, variable method yielding satisfactory cosmetic and functional results for patients suffering from chronic both-leg lymphedema. Futhermore, I suggest that the outcomes are best when treatment is administered by a multidisciplinary team including a physiotherapist, surgeon, nurse, et al.

• Archives of Craniofacial Surgery
• /
• v.20 no.6
• /
• pp.347-353
• /
• 2019

Most orbital surgeons believe that it's difficult to restore the primary orbital wall to its previous position and that the orbital wall is so thin that cannot be firmly its primary position. Therefore, orbital wall fractures generally have been reconstructed by replacing the bony defect with a synthetic implant. Although synthetic implants have sufficient strength to maintain their shape and position in the orbital cavity, replacement surgery has some drawbacks due to the residual permanent implants. In previous studies, the author has reported an orbital wall restoring technique in which the primary orbital wall fragment was restored to its prior position through a combination of the transorbital and transantral approaches. Simple straight and curved elevators were introduced transnasally to restore the orbital wall and to maintain temporary extraorbital support in the maxillary and ethmoid sinus. A transconjunctival approach provided sufficient space for implant insertion, while the transnasal approach enabled restoration of the herniated soft tissue back into the orbit. Fracture defect was reduced by restoring the primary orbital wall fragment to its primary position, making it possible to use relatively small size implant, furthermore, extraorbital support from both sinuses decreased the incidence of implant displacement. The author could recreate a natural shape of the orbit with the patient's own orbital bone fragments with this dual approach and effectively restored the orbital volume and shape. This procedure has the advantages for retrieving the orbital contents and restoring the primary orbital wall to its prior position.

• 제어로봇시스템학회:학술대회논문집
• /
• 1987.10b
• /
• pp.519-521
• /
• 1987

Among the gyroscopes used for SDINS, the dynamically turned gyroscope (DTG) covers a wide dynamic range while it is simple and small. In addition, it is a two-degree-of freedom gyro; it can detect two-axis input simultaneously. DTG, since its development in 1970's, is widely accepted for strapdown inertial systems. In the first year, we have concentrated on developing a two degree-of-freedom DIG. An interdisciplinary research team has been formed to accomplish the first year objective. Five departments in the College of Engineering, Seoul National University are involved. They are; 1) Department of Control and Instrumentation, 2) Department of Mechanical Design and Production, 3) Department of Electrical Engineering, 4) Department of Electronic Engineering, and 5) Department of Metallurgical Engineering. In addition, the Department of Precision Mechanical Engineering of Pusan National University is subcontracted to develop a test procedure for gyroscope and SDINS. Gyroscope is a key sensor for SDINS. Furthermore gyroscope itself is used as a. independent sensor for vehicle guidance and control and fire control system. Gyroscope and SDINS are an important for defense, aeronautical, and space industries that Korea is and will be actively involved. Upon the success of the project, they are expected to be manufactured in Korea under a cooperative effort between university and industry.

• Journal of Institute of Control, Robotics and Systems
• /
• v.14 no.1
• /
• pp.88-94
• /
• 2008

In this paper, a design method of a missile guidance command is presented considering the dynamics of missile control systems. The design of a new guidance command is based on the well-known PNG(propotional navigation guidance) laws. The missile control system dynamics cause the time-delays of the PN guidance command and degrade the performance of original guidance laws which are designed under the assumption of the ideal missile control systems. Using a backstepping method, these time-delay effects can be compensated. In order to implement the guidance command developed by the backstepping procedure, it is required to measure or calculate the successive time-derivatives of the original guidance command, PNG and other kinematic variables such as the relative distance. Instead of directly using the measurements of these variables and their successive derivatives, a simple disturbance observer technique is employed to estimate a guidance command described by them. Using Lyapunov method, the performance of a newly developed guidance command is analyzed against a target maneuvering with a bounded and time-varying acceleration.

• Journal of Electrical Engineering and Technology
• /
• v.10 no.3
• /
• pp.990-1001
• /
• 2015

This paper presents analysis of Switched Reluctance Machine (SRM) using Geometry Based Analytical Model (GBAM), Finite Element Analysis (FEA) and Fourier Series Model (FSM) with curve fitting technique. Further a Transient Analysis (TA) technique is proposed to corroborate the analysis. The main aim of this paper is to give in depth procedure in developing a Geometry Based Analytical Model of Switched Reluctance Machine which is very accurate and simple. The GBAM is developed for the specifications obtained from the manufacturer and magnetizing characteristic of the material used for the construction. Precise values of the parameters like Magneto Motive Force (MMF), flux linkage, inductance and torque are obtained for various rotor positions taking into account the Fringing Effect (FE). The FEA model is developed using MagNet7.1.1 for the same machine geometry used in GBAM and the results are compared with GBAM. Further another analytical model called Fourier Series Model is developed to justify the accuracy of the results obtained by the methods GBAM and FEA model. A prototype of microcontroller based SRM drive system is constructed for validating the analysis and the results are reported.

• Proceedings of the KIEE Conference
• /
• 2008.07a
• /
• pp.1466-1467
• /
• 2008

We describe here a novel micro total analysis system for the purification and identification of the affinity-captured proteins. Also we demonstrated the mass analysis of the Carcinoembrionic antigen (CEA) and Alpha femtoprotein which were chosen as the target cancer marker. For MALDI-TOF analyses, the proteins should to be separated from a protein mixture and be concentrated when needed. This procedure usually takes a long time even before protease-digested samples are to be obtained from them. Here, we describe integrated and efficient micro chip for protein purification and digestion for MALDI-TOF analyses. At first, disease protein is purified by passing the micro chamber from a protein mixture or human whole serum and released from the micro affinity beads by thermal heating. Purified protein is then transfer to the hole for trypsin digestion. The final sample is analyzed by MALDI-TOF. All the processes could be finished successfully within one hour, which renders MALDI-TOF analyses of a target protein quite simple.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.23 no.3
• /
• pp.697-705
• /
• 1996

Ankyloglossia, or tongue-tie, is a congenital condition which occurs as a result of fusion between the tongue and the floor of the mouth. Ankyloglossia often results in malocclusion with an anterior "open bite" deformity, early prognathism, swallowing problem, speech disorder, and periodontal problem. Generally lingual frenectomy is used for treatment of ankyloglossia, but incomplete operation and simple frenectomy may produce a scar contracture resulting in a more deformed ankyloglossia than was present initially. The Z-plasty is used for the correction of scar contractures and the replacement of missing tissue and this procedure is ideally suited for the treatment of an ankylosed frenum. Most authors advise postponement of any decision for surgical correction of tongue-tie until the age of 4 years, unless the child is having much difficulty with sucking or swallowing. We treated 4 patients with ankyloglossia using Z-plasty technique. As a result, we found out that it was effective for correction of movement limitation of tongue, prevention of relapse. Further, periodic check ups are needed for evaluation of relapse, improvement of speech, and other functions of the tongue.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.17 no.5
• /
• pp.36-42
• /
• 2003

This paper presents a new current-source PWM inverter based on Buck-boost configuration to interface between photovoltaic system and utility line. Proposed inverter is consisted by two set of buck-boost topology, and the input inductor is designed to be operated on the discontinuous current conduction mode. So high power factor can be achieved without additional input CtUTent controller. As a result, overall system has simple structure, and it can obtain higher ac output rms voltage than the terminal voltage of the photovoltaic system without additional boosting procedure. The operational modes are theoretically analyzed, and then the validity of the proposed system was verified through simulation and experimental results using a prototype.

• Geomechanics and Engineering
• /
• v.15 no.1
• /
• pp.621-630
• /
• 2018

In the note a comprehensive and optimal passive-active mode for describing the limit failure of circular shallow tunnel with settlement is put forward to predict the catastrophic stability during the geotechnical construction. Since the surrounding soil mass around tunnel roof is not homogeneous, with tools of variation calculus, several different curve functions which depict several failure shapes in different soil layers are obtained using virtual work formulae. By making reference to the simple-form of Power-law failure criteria based on numerous experiments, a numerical procedure with consideration of combination of upper bound theorem and stochastic medium theory is applied to the optimal analysis of shallow-buried tunnel failure. With help of functional catastrophe theory, this work presented a more accurate and optimal failure profile compared with previous work. Lastly the note discusses different effects of parameters in new yield rule and soil mechanical coefficients on failure mechanisms. The scope of failure block becomes smaller with increase of the parameter A and the range of failure soil mass tends to decrease with decrease of unit weight of the soil and tunnel radius, which verifies the geomechanics and practical case in engineering.