• 대한기계학회논문집A
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• 제32권9호
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• pp.796-803
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• 2008

Ultrasonic testing uses the directivity of the ultrasonic wave, which propagates in on direction. The directivity is expressed as the relationship between the propagate direction and its sound pressure. The directivity of an ultrasonic wave is related to the choice of probe arrangement, testing sensitivity and scanning pitch and correct measurement of defect size and location. This paper describes on the directivity measurement of ultrasonic wave using the visualization method. The directivity of shear wave emitted from the angle beam transducer were constant during propagation. The difference of directivity was existed between 2 MHz and 4 MHz angle beam transducers. When these experimental results were compared with the theory which was based on the continuous wave, it showed good agreement with theoretical directivity on the principal lobe.

• Coupled systems mechanics
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• 제3권3호
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• pp.291-304
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• 2014

Paper discusess a dynamic engineering problem of a mass attached to a pendulum sliding along a cable. In this problem the pendulum mass and the cable are coupled together in a model described by a system of differential algebraic equations (DAE). In the paper we have presented formulation of the system of differential equations that models the problem and determination of the initial conditions. The developed model is general in a sense of free choice of support location, elastic cable properties, pendulum length and inclusion of braking forces. Examples illustrate and validate the model.

• 복식
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• 제50권8호
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• pp.165-175
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• 2000

The Purposes of this study are to analyze fashion trading area's conditions of Busan area to establish fashion marketing strategies for the conditions of location in choosing the new retailers and to propose the most efficient, optimum fashion trading area(FTA) under the management mind of low cost and high efficiency according to the changes of 21C management paradigm. The subjects of investigation for this study were 1083 women visited FTA in Busan. The data were analyzed by using MANOVA, ANOVA, frequency and trend analysis, and the Cronabach $\alpha$ and Turkey HSD were also applied. The results of this study were summarized as follows. 1 The characteristics of consumer spatial behavior according to fashion trading area show significant difference in starling position, movement means, movement time, visit purpose and visit frequency. 2 The buying behavior of fashion items according to fashion trading area shows difference in fashion trading area shows difference in fashion trading area, store and buying behavior.

• Journal of Korean Neurosurgical Society
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• 제60권3호
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• pp.371-374
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• 2017

Ganglioneuroma (GN) is a rare benign tumor of neural crest origin usually found in the abdomen, but may occasionally present at uncommon sites including the cervical, lumbar, or sacral spine. However, GNs of thoracic spine are extremely rare. In this report, we describe a 12-year-old girl with giant GN in the thoracic spine, who underwent successful resection (T1-4 level) of the tumor. Histopathological examination confirmed the diagnosis. GN should be considered in the differential diagnosis of any paraspinal mass. A high index of suspicion and correlation of clinico-radiological findings is necessary in differentiating a large benign tumor from a malignant growth. Complete surgical excision is the treatment of choice; however tumor size and location need to be considered for the surgical approach (one-step or multiple surgeries). Close follow-up after surgery is mandatory.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2003년도 학술대회지
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• pp.261-266
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• 2003

The present paper theoretically investigates characteristics of moment balance of a tilting-pad thrust bearing. Pressure of lubricant film of the bearing was computed using tile finite element method, and average film temperature was estimated from the heat balance over a pad. From the investigation, it has been found that different two sets of tilt angles satisfy moment equilibrium of the pad about tile pivot for a given pivot location. The tilt angles converged depend upon initial tilt angles assumed. Quite different bearing performance, including load capacity, film thickness, and temperature, is shown to be obtained based on choice of the initial tilt angles.

• Journal of Chest Surgery
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• 제19권3호
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• pp.381-384
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• 1986

Pulmonary aspergillosis is a relatively rare disease in Korea. Immune suppressive patients, resulting from misuse or long term therapy of antibiotics, steroid and anticancer chemotherapeutics tend to be vulnerable to pulmonary aspergillosis. This study is made to illustrate the clinical features, preoperative diagnosis and surgical role in the management is this diseases. In retrospective study of operative cases from May 1980 through July 1986, 10 cases were analysis. Hemoptysis and blood tinged sputum were the most common chief complaints. Major underlying pathology was cavitary lesion or bronchiectasis caused by pulmonary tuberculosis [5 cases]. 2 cases were disseminated form due to immune suppression. Anatomic location of lesion was in the upper lobe in half case. Systemic antifungal agent is helpful for invasive aspergillosis and Resection is the treatment of choice for localized fungus balls and symptomatic localized forms.

• 대한두경부종양학회지
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• 제30권2호
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• pp.87-89
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• 2014

Epidermal cysts in mouth floor are rare. There could be confusions in diagnosis due to location and low incidence. For diagnosis, imaging study and cytology are necessary. The treatment of choice is complete excision intraorally or externally and the recurrence is rare. Some authors prefer sclerotherapy, but the follow up is necessary for malignant change. We report two cases of epidermoid cyst in submental area excised externally with literature review.

• Tribology and Lubricants
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• 제20권3호
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• pp.152-156
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• 2004

The present paper theoretically investigates characteristics of moment balance of a tilting-pad thrust bearing. Pressure of lubricant film of the bearing was computed using the finite element method, and average film temperature was estimated from the heat balance over a pad. From the investigation, it has been found that different two sets of tilt angles satisfy moment equilibrium of the pad about the pivot for a given pivot location. The tilt angles converged depend upon initial tilt angles assumed. Quite different bearing performance, including load capacity, film thickness, and temperature, is shown to be obtained based on choice of the initial tilt angles.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 추계학술대회논문집
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• pp.1072-1076
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• 2004

In automotive industry, all passenger vehicles are treated with damping materials to reduce structure borne noise. The effectiveness of damping treatments depends upon design parameters such as choice of damping materials. locations and size of the treatment. Generally, the CAE method uses modal strain-energy information of the bare structural panels to identify flexible regions, which in turn facilitates optimization of damping treatments with respect to location and size. This paper proposes a design of the damping material with a CAE(Computer Aided Engineering) methodology based on finite element analysis and DOE(Design Of Experiments) to optimize damping treatments.

• 한국정보통신학회논문지
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• 제25권9호
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• pp.1263-1266
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• 2021

The global Covid-19 pandemic has been accelerating the transition to the digital environment that enables providing consistent services without being affected by physical location or various circumstances. The Metaverse might be the representative realization reflecting this trend. In this paper, we introduce the potential core stacks consisting of the Metaverse framework in brief and explain why the open Metaverse framework is an adequate and reasonable design choice to support diverse platforms and multiple instances of the virtual world. Since the development of the open Metaverse framework is indeed in a very early stage, achieving technical completeness in each building block of the open Metaverse is crucial. Considering the expansion and spread of the Metaverse in the future, intensive standardization studies on the open Metaverse framework are exigent and indispensable.