• The Korean Journal of Cytopathology
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• v.9 no.2
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• pp.187-191
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• 1998

Alveolar soft part sarcoma(ASPS) is a rare malignant neoplasm with a distinct clinicopathologic entity of which fine needle aspiration(FNA) cytologic findings have been described in only a few reports. Although patients usually present with an isolated soft-tissue mass in the extremity, metastasis can occur in about 13 % of total cases and the most frequent metastatic site is the lung. We have recently experienced a FNA cytologic case of ASPS in the lung. A 23-year-old female patient was admitted to this hospital due to 2-month-history of cough She had been good in health before the visit. Chest computed tomography revealed multiple, variable sized, bilateral pulmonary nodules. Physical examination and other staging work up revealed no other lesions except for pulmonary nodules. A percutaneous transthoracic FNA was performed from the pulmonary nodules. The smear was cellular and most cells were arranged singly. In addition, a few clusters lined by thin-walled vasculature with a pseudoalveolar pattern were present. Some of the tumor cells were large and polygonal lo oval with abundant granular or vacuolated cytoplasm. Most cells were naked nuclei showing finely granular chromatin pattern with prominent central nucleoli.

• Smart Structures and Systems
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• v.18 no.1
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• pp.155-181
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• 2016

In the present paper we discuss the stability and the post-buckling behaviour of thin piezoelastic plates. The first part of the paper is concerned with the modelling of such plates. We discuss the constitutive modelling, starting with the three-dimensional constitutive relations within Voigt's linearized theory of piezoelasticity. Assuming a plane state of stress and a linear distribution of the strains with respect to the thickness of the thin plate, two-dimensional constitutive relations are obtained. The specific form of the linear thickness distribution of the strain is first derived within a fully geometrically nonlinear formulation, for which a Finite Element implementation is introduced. Then, a simplified theory based on the von Karman and Tsien kinematic assumption and the Berger approximation is introduced for simply supported plates with polygonal planform. The governing equations of this theory are solved using a Galerkin procedure and cast into a non-dimensional formulation. In the second part of the paper we discuss the stability and the post-buckling behaviour for single term and multi term solutions of the non-dimensional equations. Finally, numerical results are presented using the Finite Element implementation for the fully geometrically nonlinear theory. The results from the simplified von Karman and Tsien theory are then verified by a comparison with the numerical solutions.

• Journal of applied mathematics & informatics
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• v.7 no.2
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• pp.493-506
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• 2000

Recently the first author and his coworker report a new finite element method for the Poisson equations with homogeneous Dirichlet boundary conditions on a polygonal domain with one re-entrant angle [7], They use the well-known fact that the solution of such problem has a singular representation, deduced a well-posed new variational problem for a regular part of solution and an extraction formula for the so-called stress intensity factor using tow cut-off functions. They use Fredholm alternative an Garding's inequality to establish the well-posedness of the variational problem and finite element approximation, so there is a maximum bound for mesh h theoretically. although the numerical experiments shows the convergence for every reasonable h with reasonable size y imposing a restriction to the support of the extra cut-off function without using Garding's inequality. We also give error analysis with similar results.

• Journal of Oral Medicine and Pain
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• v.3 no.1
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• pp.3-10
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• 1977

Few changes were found in the mouths of 52 smokers were examined as a part of program to evaluate the oral health of Korean smokers. 52 smokers and 30 non-smokers were performed careful oral examination. In many of smokers, heavy, black deposits are found on the buccal and lingual surfaces of the teeth and leukoplakia were obsreved in 2 subjects and varied merely in the severity of the involvement. Cytologic studies were carried out on 60 oral smears from the hard palate, buccal mucosa, and gingiva. Smears were taken wit a wood spatula scraped over the mucosal surface. After fixation the slides were stained using the papanicolau cells without nuclei. The cornified cells were smaller than the noncornified cells and stained a deep brown or orange as compared with the blue or red of the large, round or polygonal cells in nonkeratinized regions of oral mucosa. Abnormal cell forms, suggestive of malignancy were not found in smears from the mucosa of smokers. Cells with large hyperchromatic nuclei and elongated, spindle-type cells with large nuclei were not observed.

• Journal of the Korean Society of Industry Convergence
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• v.5 no.2
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• pp.141-146
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• 2002

Stereolithography is the best known as rapid prototyping system. It uses the STL format data which is generated from CAD system. In this study, One of the main function of this developed CAM system deals with shape modification which divide a shape into two parts or more. The cross section of a STL part by a z-level is composed with nested or single polygonal closed loop. In order to make RP product, closed loops must fill with triangular facets from SSET and recover sliced triangular facets which is located normal direction to the cross sectional plane. The system is development by using Visuall C++ compiler in the environment of pentium PC. Operating system is Windows NT workstaion from Micro-Soft.

• Proceedings of the KOSOMBE Conference
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• v.1994 no.12
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• pp.101-103
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• 1994

The film scanner that digitizes the conventional x-ray films is the necessary equipment in the transition period of going to the filmless hospital. We have developed the film scanner using laser. We have selected HeNe laser as light source. The polygonal mirror converts the point light source to line scanning light. In sensing part, the diffusing cylinder and 7 photo transistors converts the light signal which passing the film into the electric signal. With this scanner, we can scan successfully the conventional x-ray film by $1024\times1024$. Smaller the spot sire is, higher the resolution can be achieved.

• Structural Engineering and Mechanics
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• v.7 no.3
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• pp.289-302
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• 1999

An approximate method for analyzing the bending problems of irregular-shaped plates is proposed. In this paper irregular-shaped plates are such plates as plate with opening, circular plate, semi-circular plate, elliptic plate, triangular plate, skew plate, rhombic plate, trapezoidal plate or the other polygonal plates which are not uniform rectangular plates. It is shown that these irregular-shaped plates can be considered finally as a kind of rectangular plates with non-uniform thickness. An opening in a plate can be considered as an extremely thin part of the plate, and a non-rectangular plate can be translated into a circumscribed rectangular plate whose additional parts are extremely thin or thick according to the boundary conditions of the original plate. Therefore any irregular-shaped plate can be replaced by the equivalent rectangular plate with non-uniform thickness. For various types of irregular-shaped plates the convergency and accuracy of numerical solution by proposed method are investigated.

• Korean Journal of Heritage: History & Science
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• v.53 no.1
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• pp.126-149
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• 2020

Considering significant words that stand for the history of Paleolithic in North Korea, these can be summarized for each decade since the 1960s. The 1960s ought to be when the earliest discovery of a Paleolithic site was made by Korean hands. The 1970s might be the earliest period for textbooks being published that were geared towards increasing general understanding of the Paleolithic era in the Korean peninsula. The 1980s can be summarized as a period of reissued Paleolithic articles from a newly introduced archaeological journal. The 1990s witnessed efforts to formulate nationalistic interpretations about the Paleolithic period in Korea. The 2000s then synthesized several of these aspects of Paleolithic studies. Gulpori, the Paleolithic site that was discovered in the 1960s, holds significance not just because of the discovery itself, but because of its prompt acceptance by North Korean academic authorities. The publications that covered general understanding of Paleolithic archaeology such as Joseon Gogohag Gaeyo, Joseon-ui Guseoggisidae, and Joseonjeonsa: Wonsipyeon in the 1970s hold immense significance themselves, as they demonstrate contemporary achievements. Reintroduction of the archaeological Journal, Joseongogoyeongu in 1986, is the beacon of alleviation of conspicuous effect to the academic sector. During the 1990s, a new emphasis on nationalism influenced Paleolithic studies. In the 2000s, the formally constructed elements of Paleolithic research such as Paleolithic chronology, social evolution, lithic assemblage, Quaternary studies, and human evolution were consistently refined. Metaphorically speaking, these parts are like a polygonal structure. As is the case with a polygonal structure, these research aspects are united and work together. Each part affects the others. Although the content of each research aspect has been altered by either academic growth or sociopolitical agenda, the fundamental part of the polygonal structure is not likely to be changed. The structure is solid enough to continue to serve the purposes of North Korean Paleolithic studies. North Korean Paleolithic archaeology seems to be a juxtaposition; some parts are easily changed while others are not. In order to ascertain these, not only the academic but also the sociopolitical context should be followed.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.20 no.3
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• pp.342-349
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• 2011

The purpose of this paper is to describe experimental results about the butt welding and bead on plate welding of the high power Continuous Wave (CW) Fiber laser for Ultra-low carbon Interstitial Free(IF) steel plate for gear part of car. After being welded of the gear parts by the fiber laser and electron beam Microstructures of melting zone had been mixed acicular, granular bainitic, quasi-polygonal and widmanstatten ferrite because of a radical thermal diffusion after welding, difference of critical volume and grain size. As a result of experiment, when gear parts were welded by the fiber laser and electron beam, the fiber laser welding has been stable properties without internal defects more than the electron beam welding. Therefore it has the very advantages of welding high quality and productivity more than conventional melting method. The optimal welding processing parameters for gear parts were as follows : the laser power and welding speed were 3kWatt, 30mm/sec respectively. At this time heat input was $21.2{\times}10^3J/cm^2$.

• Journal of Welding and Joining
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• v.35 no.3
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• pp.68-74
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• 2017

Characteristics of dissimilar metal welds between alloy steel ASTM A387 Gr. 91 and carbon steel ASTM A516 Gr.70 made with Flux cored arc welding(FCAW) have been evaluated in terms of microstructure, mechanical strength, chemical analysis by EDS as well as corrosion test. Three heat inputs of 15.0, 22.5, 30.0kJ/cm were employed to make joints of dissimilar metals with E71T-1C wire. Post-weld heat treatment was carried out at $750^{\circ}C$ for 2.5 h. Based on microstructural examination, Intragranular polygonal ferrite and grainboundary ferrite were formed only in first layer of weld metal. Another layers consisted of acicular ferrite and $Widmannst{\ddot{a}}tten$ ferrite. The amount of acicular ferrite was increased with decreasing heat input and layer. Heat affected zone of alloy steel showed the highest hardness due to the formation of tempered martensite and lower bainite. Lower and upper bainite were formed in heat affected zone of carbon steel. Tensile strengths of dissimilar metal welds decreased with increasing heat inputs. Dissimilar metal welds showed a good hot cracking resistance due to the low HCS index below 4. The salt spray test of dissimilar metals welds showed that the weight loss rate by corrosion below 170 hours was decreased with increasing heat inputs due to the increase of the amount of acicular ferrite.