• The Korean Journal of Cytopathology
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• v.2 no.2
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• pp.142-147
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• 1991

Diagnosis of a thymic carcinoid was made on transthoracic fine needle aspiration in a 36-year old woman who had an anterior mediastinal mass on chest X-ray and CT scan. The aspiration smears showed numerous anastomosing ribbons and cords of small round tumor cells. The tumor cells had slightly eccentric nuclei and some granular cytoplasm. The small and uniform nuclei of the tumor cells had finely granular chromatin and thin nuclear membrane. The cytologic diagnosis of a carcinoid was confirmed on histopathologic, immunohistochemical, and electromicroscopic examination of surgical specimen.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.05a
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• pp.313-318
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• 2003

The vibration of washing machine at spinning cycle is important problem that affects the performance of a product. In this raper, the inner structure of the washing machine is modeled as a rigid body suspension system and transfer farce caused by rotating unbalance mass is obtained using Newton's the 2nd law. and this model is used to predict the verge of walking instability during the spinning cycle. The walk of the drum washing machine is suggested by calculating the force transmissibility between drum and the cabinet. As calculating the resultant force exerted for cabinet, the friction coefficient of the pad is suggested to avoid the walk. In addition, relation between translational slip and rotational slip is derived and method to avoid the rotational slip is introduced.

• Transactions of the Korean hydrogen and new energy society
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• v.22 no.6
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• pp.794-799
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• 2011

In order to reduce the oil consumption for a 2 stroke free piston hydrogen fueled engine, the behaviors of residual lubricant oil of the cylinder wall surface were visualized and oil mass emitted into exhaust port was measured by using research engine with cross-head and eccentric crankshaft. As the results, it was shown that characteristics of residual lubricant oil such as oil thickness and distribution were remarkably different from a conventional 4 stroke engine. It was also analyzed that these tendencies relied on the configuration and installed position of the exhaust port, piston pin boss and so on.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.20 no.7
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• pp.637-643
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• 2010

The paper is about the development of 6-DOF active vibration isolation systems using VCM. Firstly, formulate the vertical 3-DOF mathematical model under eccentric load, and compare the model with the case in which the center of mass is located at the centroid. And then, complete the 6-DOF mathematical model by formulating the horizontal 3-DOF mathematical model. Find main parameters by comparing the result of the frequency response test with simulation result on the model. Finally, achieve the performance of vibration isolation by applying loop shaping approach & feedforward controller.

• Earthquakes and Structures
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• v.1 no.2
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• pp.163-175
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• 2010

The vertical axis through the modal center of rigidity (m-CR) is used for interpreting the code torsional provisions in the design of eccentric multi-story building structures. The concept of m-CR has been demonstrated by the author in an earlier paper and the particular feature of this point is that when the vertical line of the centers of mass at the floor levels is passing through m-CR, minimum base torsion is developed. For this reason the aforesaid axis is used as reference axis for implementing the code provisions required by the equivalent static analysis. The study examines uniform mixed-bent-type multistory buildings with simple eccentricity, ranging from torsionally stiff to torsionally flexible systems. Using the results of a dynamic response spectrum analysis as a basis for comparisons, it is shown that the results of the code static design are on the safe side in torsionally stiff buildings, but unable to predict the required strength of bents on the stiff side of systems with a predominantly torsional response. Suggestions are made for improving the code provisions in such cases.

• Archives of Plastic Surgery
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• v.38 no.4
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• pp.494-497
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• 2011

Purpose: Schwannoma, a benign peripheral nerve tumor, is slow-growing, encapsulated neoplasm that originates from the Schwann cell of the nerve sheath. Schwannoma most frequently involves the major nerve. Schwannoma occurring in the superficial radial nerve rare. This is a report of our experience with schwannoma arising from the superficial radial nerve with neurologic symptom. Methods: A 55-year-old woman presented with eight-month history of progressive numbness and paresthesia in dorsum of the thumb and index finger. Physical examination revealed a localized mass on the midforearm. Sonographic examination showed an ovoid, heterogenous, hypoechoic lesion, located eccentrically in related to the superficial radial nerve. The lesion was mobile in the transverse but not in the longitudinal axis of the nerve, which was thought to favour schwannoma rather than neurofibroma. At operation, a $20{\times}15mm$ ovoid, yellowish grey mass was seen arising from the superficial radial nerve. The tumor present as eccentric masses over which the nerve fibers are splayed. Using operating microscope, the tumor was removed, preserving the surrounding nerve. Results: Histology confirmed that the mass was a benign schwannoma. There were no postoperative complications. After two months the patient had no clinically demonstrable sensory deficit. Conclusion: An unsusual case of a schwannoma of the superficial radial nerve is presented. In case with neurologic symptom, prompt surgical decompression must be made to prevent further nerve damage and to restore nerve function early.

• Earthquakes and Structures
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• v.8 no.2
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• pp.463-484
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• 2015

Modern codes for earthquake resistant building design require consideration of the so-called accidental design eccentricity, to account for torsional response caused by several factors not explicitly considered in design. This provision requires that the mass centres in the building floor be moved a certain percentage of the building's dimension (usually 5%) along both the x and y axes and in both positive and negative directions. If one considers also the spatial combinations of the two component motion in a dynamic analysis of the building, the number of required analyses and combinations increases substantially, causing a corresponding work load increase for practicing structural engineers. Another shortcoming of this code provision is that its introduction has been based primarily on elastic results from investigations of oversimplified, hence questionable, one story building models. This problem is addressed in the present paper using four groups of eccentric braced steel buildings, designed in accordance with Eurocodes 3 (steel) and 8 (earthquake design), with and without accidental eccentricities considered. The results indicate that although accidental design eccentricities can lead to somewhat reduced inelastic response demands, the benefit is not significant from a practical point of view. This leads to suggestions that accidental design eccentricities should probably be abolished or perhaps replaced by a simpler and more effective design provision, at least for torsionally stiff buildings that constitute the vast majority of buildings encountered in practice.

• International Journal of Control, Automation, and Systems
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• v.3 no.3
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• pp.387-396
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• 2005

The Rotational/Translational Actuator (RTAC) benchmark problem considers a fourth-order dynamical system involving the nonlinear interaction of a translational oscillator and an eccentric rotational proof mass. This problem has been posed to investigate the utility of a rotational actuator for stabilizing translational motion. In order to experimentally implement any of the model-based controllers proposed in the literature, the values of model parameters are required which are generally difficult to determine rigorously. In this paper, an approach to the least-squares estimation of the parameters of a system is formulated and practically applied to the RTAC system. On the other hand, this paper shows how to model a nonlinear system as a linear uncertain system via nonparametric system identification, in order to provide the information required for linear robust $H_\infty$ control design. This method is also applied to the RTAC system, which demonstrates severe nonlinearities, due to the coupling from the rotational motion to the translational motion. Experimental results confirm that this approach can effectively condense the whole nonlinearities, uncertainties, and disturbances within the system into a favorable perturbation block.

• The Korean Journal of Cytopathology
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• v.9 no.1
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• pp.99-104
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• 1998

Anaplastic large cell lymphoma(ALCL) is an uncommon type of non-Hodgkin's lymphoma(NHL) populated with anaplastic, often bizarre cells that express CD30 (Ki-1) antigen. The unusual histologic and cytologic features may cause confusion with other neoplasms, such as poorly differentiated carcinoma, melanoma, Hodgkin's disease, or true histiocytic lymphoma. Although the cytologic features of ALCL have been well described, there are few reports about cytologic findings of the sarcomatold variant of ALCL. We experienced a case of fine needle aspiration(FNA) cytologic findings of ALCL which mimicks malignant fibrous histiocytoma. FNA cytology of chest wall mass in a 62-year-old female with a history of peripheral T-cell lymphoma(Lennert lymphoma) revealed a heterogeneous population of single cells and poorly cohesive cells with large, pleomorphic nuclei and spindle cells gathering around vascular structures within an inflammatory background. Additional features of the neoplastic cells were eccentric, multilobated nuclei with occasional 'wreath-like' configuration; abundant cytoplasm with vacuolization; and prominent nucleoli. The cytologic features suggested sarcoma, especially malignant fibrous histiocytoma. The diagnosis was made retrospectively with an aid of immunocytochemical staining.

• The Korean Journal of Cytopathology
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• v.9 no.1
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• pp.111-115
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• 1998

Although the characteristic cytologic features of melanoma have been well described the diagnosis of metastatic melanoma by fine needle aspiration cytology (FNAC) may be difficult in the case of amelanotic melanoma and in the absence of awareness of clinical history. Furthermore, when the breast is the site of initial presentation, it could simulate a primary breast carcinoma leading to misdiagnosis. The recognition of metastatic malignant melanoma in FNAC material is essential to avoid an unnecessary mastectomy and to ensure appropriate chemotherapy. We experienced a case of metastatic melanoma of breast which presented as solitary breast mass in a 56-year-old woman. She had a history of surgical excision of right foot for melanoma one year ago. The cytologic smears were composed of noncohesive epithelioid cells with round or eccentric nuclei, bi-or multi-nucleation, prominent nucleoli, fine chromatin, and intranuclear inclusions. The cytoplasm of tumor cells had scanty melanin pigment but were diffusely positive for S-100 protein.