• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.05a
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• pp.833-838
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• 2003

The problem of elastic wave resonance scattering from elastic targets is studied in this paper. A new resonance formalism to extract the elastic resonance information of the target from scattered elastic waves is introduced. The proposed resonance formalism is an extension of the works developed for acoustic wave scattering problems by the author. The classical resonance scattering theory computes reasonable magnitude information of the resonances in each partial wave, but the phase behaves in somewhat irregular way, therefore, is not clearly explainable. The proposed method is developed to obtain physically meaningful magnitude and phase of the resonances. As an example problem, elastic wave scattering from an infinitely-long elastic cylinder was analyzed by the proposed method and compared to the results by RST. In case of no mode conversion, both methods generate identical magnitude. However, the new method computes exact $\pi$ radian phase shills through resonances and anti-resonances while RST produces physically unexplainable phases. In case of mode conversion, in addition to the phase even magnitudes are different. The phase shifts through resonances and antiresonances obtained by the proposed method are not exactly $\pi$ radians due to energy leak by mode conversion. But, the phases by the proposed method show reasonable and intuitively correct behavior compared to those by RST.

• Journal of Institute of Control, Robotics and Systems
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• v.12 no.8
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• pp.780-788
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• 2006

This paper deals with INS/GPS tightly coupled integration algorithms using extend Kalman filter (EKF) and unscented Kalman filter (UKF). In the tightly coupled approach, nonlinear pseudorange measurement models are used for the INS/GPS integration Kalman filter. Usually, an EKF is applied for this task, but it may diverge due to poor functional linearization of the nonlinear measurement. The UKF approximates a distribution about the mean using a set of calculated sigma points and achieves an accurate approximation to at least second-order. We introduce the generalized scaled unscented transformation which modifies the sigma points themselves rather than the nonlinear transformation. The generalized scaled method is used to transform the pseudo range measurement of the tightly coupled approach. To compare the performance of the EKF- and UKF-based tightly coupled approach, real van test and simulation have been carried out with feedforward and feedback indirect Kalman filter forms. The results show that the UKF and EKF have an identical performance in case of the feedback filter form, but the superiority of the UKF is demonstrated in case of the feedforward filer form.

• The Journal of the Korean bone and joint tumor society
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• v.12 no.2
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• pp.155-160
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• 2006

Giant cell-rich osteosarcoma is a rare tumor that is hard to distinguish from giant cell tumors of bone. The location and radiographic aspect of these tumors can be identical. The histologic differentiation between a giant cell-rich osteosarcoma and a giant cell tumor can be difficult. Due to the different prognosis and treatment strategies of these tumors it is essential to make the right diagnosis at presentation. This article reports a case of a giant cell-rich osteosarcoma of the proximal tibia that initially was diagnosed histologically as a giant cell tumor by needle biopsy.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.9
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• pp.1188-1191
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• 2004

Two species of marine catfish, Arius maculatus and Osteogeneiosus militaris, belonging to family Ariidae were analysed electrophoretically for genetic variation in 6 enzymes, alcohol dehydrogenase (ADH), malate dehydrogenase (MDH), lactate dehydrogenase (LDH), glucose dehydrogenase (GDH), malic enzyme (ME) and superoxide dismutase (SOD). Eighteen individuals of each species were studied. Two loci MDH and ADH were polymorphic in both. Average heterozygosity in A. maculatus was 1.46, while it was 2.5 in O. militaris. The allele frequencies were used to estimate Nei's genetic distance (D). The D value was calculated to be 0.6879. Two isozyme loci, ME and SOD, were found to be the most reliable species specific markers. No tissue specific loci were observed for the enzymes studied, the bands being identical in each case. The genetic distance observed between O. militaris and A. maculatus in this study suggests that they would be more appropriately classified as species of the same genus rather than being assigned separate genera.

• Journal of the korean Society of Automotive Engineers
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• v.7 no.1
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• pp.48-54
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• 1985

One of the most probable reason of the apex seal damage in IR-2500 industrial Wankel (rotary) engine was believed to be the engine detonation. Both analytical and experimental studies were made with a view th find out engine detonation pressure. The stagnation detonation pressure $p_{03}$' was estimated based on the data from IR-2500 engine detonation tests, such as engine firing pressure, state of fresh charge at BDC and polytropic compression exponent. The estimated stagnation detonation pressure for the natural gas fueled IR-2500 engine was in excess of 3,700 psia. With natural gas liquid added to the natural gas the octane value of the fuel was lowered, thus, making the engine more prone to detonate. The estimated detonation pressure for the case with the mixed fuel was about 3,400 psia which was sufficiently high to break the apex seal. The subsequent engine lab tests performed on two identical engines with sole difference in the apex seal thickness between the two engines proved that the engine knock, in fact, was the villain of the apex seal failure.ilure.

• Mycobiology
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• v.30 no.3
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• pp.139-145
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• 2002

Gibberella fujikuroi is species complex. This species complex includes Fusarium tabacinum, F. moniliforme(=F. verticillioides), F. nygamai, F. proliferatum as well as F. subglutinans. Our objective was to develop a technique to differentiate between isolates of F. subglutinans, F. proliferatum and F. verticillioides. Thirty-two strains of F. subglutinans, six strains from F. verticillioides and five strains of F. Proliferatum isolated from maize in Austria were studied using random amplified polymorphic DNA(RAPD). F. subglutinans strains clustered very closely, with similarity ranging from $87{\sim}100%$. On the other hand, all the amplification patterns of F. verticillioides were identical, as well as in the case of F. proliferatum. Our results indicated that these Fusaria species are distinct species and hence RAPD markers can be quick and reliable for differentiating them.

• Advances in nano research
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• v.1 no.4
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• pp.203-210
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• 2013

So far, all reviews and control approaches of spin relaxation have been done on lateral single electron quantum dots. In such structures, many efforts have been done, in order to eliminate spin-lattice relaxation, to obtain equal Rashba and linear Dresselhaus parameters. But, ratio of these parameters can be adjustable up to 0.7 in a material like GaAs under high-electric field magnitudes. In this article we have proposed a single electron QD structure, where confinements in all of three directions are considered to be almost identical. In this case the effect of cubic Dresselhaus interaction will have a significant amount, which undermines the linear effect of Dresselhaus while it was destructive in lateral QDs. Then it enhances the ratio of the Rashba and Dresselhaus parameters in the proposed structure as much as required and decreases the spin states up and down mixing and the deviation angle from the net spin-down As a result to the least possible value.

• Journal of Chest Surgery
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• v.46 no.6
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• pp.482-485
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• 2013

Plasmacytoma is a plasma cell neoplasm that locally infiltrates a bone or spreads to extramedullary areas. A new World Health Organization criterion defines solitary plasmacytoma of bone as a localized bone tumor consisting of plasma cells identical to those seen in plasma cell myeloma, which is manifested as a solitary osteolytic lesion in a radiological evaluation. Primary tumors of the sternum are generally malignant, and solitary plasmacytomas of the sternum are very rare tumors. We present herein the case of a patient who had a primary sternal tumor with solitary plasmacytoma and no evidence of multiple myeloma.

• Journal of Mechanical Science and Technology
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• v.16 no.12
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• pp.1664-1672
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• 2002

Gantry mechanisms have been widely used for precision manufacturing and material handling in electronics, nuclear, and automotive industries. Dual-drive servo mechanism is a way to increase control bandwidth, in which two primary axes aligned in parallel are synchronously driven by identical servo motors. With this mechanism, a flexible coupling (compliance mechanism) is often introduced in order to avoid the damage by the servo mismatch between the primary drives located at each side of gantry. This paper describes the design guidelines of the dual-drive servo mechanism with focus on its dynamic characteristics and control ramifications. That is, the effect on the system bandwidth which is critical on the system performance, the errors and torques exerted on guide ways in case of servo mismatch, the vibration characteristics concerned with dynamic error and settling time, and the driving force required at each axis for control are thoroughly investigated.

• Journal of Chest Surgery
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• v.31 no.6
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• pp.638-641
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• 1998

A recurrent myoepithelioma of the lung in a 36-year-old man is reported. The neoplasm showed histologic features identical to those described in myoepitheliomas of major and minor salivary glands on the basis of Dardick's morphological classification of Myoepitheliomas. He was treated totally with surgical en-bloc resection including the chest wall. The tumor was found to be well encapsulated, and it appeared to be mainly composed of plasmacytoid cells and clear cells with occasional microcystic spaces in a solid growth form by light microscopy. Immunocytochemical, ultrastructural and flow-cytometrical studies supported myoepithelioma differentiation.