• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11b
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• pp.301-305
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• 2002

Among many structural dynamics modification methods for plate and shell vibration problems, embedding an emboss to the surface is very efficient. But deciding an optimal position and shape using optimization algorithm needs defining geometry and remeshing the model for every iteration step to implement the method, which takes much numerical cost. An equivalent element produced here lessen the cost by representing the geometrical characteristics of an emboss using the element's material properties and thickness becoming a geometrically homogenous element of the base plate or shell. Some efficient factors which let the equivalent system have the same dynamical response as the original system embedded with emboss will be shown and the degree of equivalence will be tested in terms of natural frequency matching.

• Journal of Chest Surgery
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• v.11 no.2
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• pp.165-169
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• 1978

Hemangiopericytoma is a rare tumor of vascular origin, first described by Stout and Murray in 1942. It is characterized by a proliferation of capillaries, surrounding by a mass of spindle shaped or round cells. A 55 year-old man was admitted with a 2 years history of dull pain on the right upper posterior chest and mild dyspnea on Feb. 1978. On admission, chest PA and right lateral x-ray showed a large well defined homogenous increased density in the right upper posterior chest. Yellowish to brownish colored huge firm mass, which occupied entirely the right superior posterior mediastinum, was removed. The tumor was dense adhesive with right upper & lower lobe and Rt. upper posterior chest wall. The origin of tumor was not obvious. The tumor was confirmed as hemangiopericytoma, locating at the right posterior mediastinum by histopathologic examination. The postoperative course was uneventful, and he was made irradiation therapy after discharge.

• Applied Microscopy
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• v.23 no.1
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• pp.25-34
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• 1993

Prolactin has been reported to be present in the tear film of humans and prolactin-like immunoreactivity has been detected by immunofluorescence in acinar cells of the lacrimal glands of humans and rats. The present study was aimed at clarifying the intracellular distribution of the prolactin-like immunoreactivity, using the electron microscope immunogold technique. The lacrimal gland acinar cells have two types of secretory granules: 1) Secretory granules containing flocculent materials irregularly shaped and are often coalesced. 2) Secretory granules are fairly round and contain homogenous materials of a moderate electron density. The density of the granular content varies even within a single cell. We found prolactin-like reactivity in secretory granules, some smaller cytosolic vesicles, Golgi cisternae and nuclei in acinar cells from intact glands of rat. Our present results are consistent with the conclusion that prolactin is present in lacrimal cells. The presence of prolactin reactivity in the nucleus suggests that prolactin may be a regulatory factor modulating gene expression.

• Journal of the Korean Operations Research and Management Science Society
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• v.1 no.1
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• pp.127-138
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• 1976

Economists have become interested in the centralization and decentralization of planning, in the linking up of models into a homogenous model system, and in multi-level planning. In this study, Input/Output techniques used for explaining the resource allocation mechanisms to be more rational through detailed specifications of a large organization's objectives and explicit linking of centralization and decentralization to such objectives. Also the application of mathematical methods to the higher levels of planning in the optimal allocation resources can't fully describe the actual practice of planning. On the other hand, 1-0 techniques are standard in economic analysis and planning. However, the application procedures to the armed forces hold only when their assumptions are met and when their solutions are convergent. So, it is of limited applicability.

• Structural Engineering and Mechanics
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• v.54 no.1
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• pp.135-148
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• 2015

The present investigation is concerned with a study effect of magnetic field and non-homogenous on the elastic stresses in rotating orthotropic infinite circular cylinder. A certain boundary conditions closed form stress fields solutions are obtained for rotating orthotropic cylinder under initial magnetic field with constant thickness for three cases: (1) Solid cylinder, (2) Cylinder with a circular hole at the center, (3) Cylinder mounted on a circular rigid shaft. Analytical expressions for the components of the displacement and stress fields in different cases are obtained. The effect of rotation and magnetic field and non-homogeneity on the displacement and stress fields are studied. Numerical results are illustrated graphically for each case. The effects of rotating and magnetic field and non-homogeneity are discussed.

• Journal of Biomedical Engineering Research
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• v.29 no.4
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• pp.267-271
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• 2008

The RF shimming technique has been used to improve the transmit RF field homogeneity in highfield MRI. In the RF shimming technique, the amplitude and phase of the driving currents in each coil element are optimized to get homogenous flip angle or uniform image intensity. The inductive and capacitive coupling between the coil elements may degrade the RF field homogeneity if not taken into account in the optimization procedure. In this paper, we have analyzed the coupling effects on the RF shimming using a sixteen-element TEM RF coil model operating at 300 MHz. We have found that the coupling effects on the RF shimming can be reduced by putting high dielectric material between the active rung and the shield.

• Structural Engineering and Mechanics
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• v.51 no.6
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• pp.1067-1089
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• 2014

In this paper, three dimensional static and dynamic analyses of two dimensional functionally graded annular sector plates have been investigated. The material properties vary through both the radial and axial directions continuously. Graded finite element and Newmark direct integration methods have been used to solve the 3D-elasticity equations in time and space domains. The effects of power law exponents and different boundary conditions on the behavior of FGM annular sector plate have been investigated. Results show that using 2D-FGMs and graded elements have superiority over the homogenous elements and 1D-FGMs. The model has been compared with the result of a 1D-FGM annular sector plate and it shows good agreement.

• Smart Structures and Systems
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• v.4 no.5
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• pp.531-548
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• 2008

Recently, dense sensor instrumentation for structural health monitoring has motivated the need for novel passive wireless sensors that do not require a portable power source, such as batteries. Using a layer-by-layer self-assembly process, nano-structured multifunctional carbon nanotube-based thin film sensors of controlled morphology are fabricated. Through judicious selection of polyelectrolytic constituents, specific sensing transduction mechanisms can be encoded within these homogenous thin films. In this study, the thin films are specifically designed to change electrical properties to strain and pH stimulus. Validation of wireless communications is performed using traditional magnetic coil antennas of various turns for passive RFID (radio frequency identification) applications. Preliminary experimental results shown in this study have identified characteristic frequency and bandwidth changes in tandem with varying strain and pH, respectively. Finally, ongoing research is presented on the use of gold nanocolloids and carbon nanotubes during layer-by-layer assembly to fabricate highly conductive coil antennas for wireless communications.

• Architectural research
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• v.18 no.3
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• pp.91-102
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• 2016

This study examines modernist grid and boundary in the works of Toyo Ito - two of the most important notions characterizing the development of Toyo Ito as an iconoclast architect. Early in his career, Ito recognized modernist architecture's inherent tendencies to establish homogenous order and divide space by function was alienating people from their context. Ito identified the notions of modernist grid and boundary as the agents of Modernism which inadvertently served to impose this systematic order and severe separation. As a reaction against these tendencies, Ito sought to avoid the use of modernist grid and blur boundary in his architecture. In Ito's career spanning over four decades, he engages in an exhaustive inquiry seeking to modify these two core elements of architecture. This study investigates these two notions in Ito's works and examines the significance of the architect's exploration in the context of Japan's Modernism.

• Proceedings of the KSRS Conference
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• v.2
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• pp.676-679
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• 2006

Mangrove crowns were delineated using active sensor LIDAR (LIght Detection And Ranging) data by a crown delineating model developed in this study. LIDAR data were acquired from airborne survey by a helicopter for the estuary of Macouria in the northeast coast of French Guiana. The canopy height image was derived from LIDAR vector data by calculating the difference between ground and non-ground data. The mangrove site in the study area was classified to three sectors by the time of mangrove settlement; Mangrove 1986, 2002 and 2003. The estimated crown of Mangrove 1986 was reliable defined for their size, number and volume because of larger crown size and bigger variation of crown height. The tree crown size of Mangrove 2002 and 2003 by the model was overestimated and the number of trees was much underestimated. The estimated crown was not for single crown but a crown group due to homogenous crown height and spatial resolution of LIDAR data. However the canopy height image derived from LIDAR data provided three-dimensional information of mangroves.