• Journal of the Korean Society for Precision Engineering
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• v.15 no.6
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• pp.124-138
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• 1998

Particles reinforced MMCs have many advantages over monolithic metals including a higher specific modulus, higher specific strength, better properties at elevated temperatures and better wear resistance. SiC$_p$/A16061 composites have good results in its mechanical properties. This work investigates SiC$_p$/A16061 composites in the microscopic view and compares the analytical results with the experimental ones. The discrepancy of the material properties between the reinforced particle, SiC$_p$, and the matrix material, A16061 appears to be so significant. Especially the coefficient of thermal expansion(CTE) of A16061 is 5 times larger than that of SiC$_p$. Thermal residual stress in MMCs is induced at high temperatures. The shape of particle is various but the theoretical model is not able to consider the nonuniform shape. Particle distribution is not homogeneous in experimental specimen. However, it is assumed to be homogeneous in simulation model. The shapes of particles are assumed to be not only perfect global but hexahedral shapes. The types of particle distribution are two - simple cubic array(SC array) and face-centered cubic array(FCC array).

• Journal of the Korean Home Economics Association
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• v.39 no.12
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• pp.65-77
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• 2001

The purpose of this study is to propose development of simulation for make-up coordination by computer graphics and web animation program. In the 20th century, the power of the internet and www has been growing at such a rapid speed and also has provided the possibility of numerous market. Especially the internet marketing of womens products like cosmetics come into the spotlight as the way of sales. Many companies advertise their new products and give useful guidline of make-up technic on the website. So the contents of the website is one of the important thing to lead customer to purchasing. For the reason, this study tries develope a simulation of model in which customer can select their shape of face, color and theme whatever necessary. The model, color, theme palletes were designed by 'PHOTOSHOP 6.0'and the web image of simulation was made by 'FLASH ANIMATION 5.0'. As a result of this study is 1. It can give the chance to customer to make their own image of shape, color and theme through the simulation more speedly and exactly. 2. It can help company to advertise their new products, offer service for customers and lead customers to purchasing. 3. By accummulating the database, it can help to develop educational make-up system.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.05a
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• pp.207-212
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• 2009

In order to optimize the press formability of incremental sheet forming for complex shape (e.g human face), a combination of both CAM and FEM simulation, is implemented and evaluated from the histories of stress and strain value by means of finite element analysis. Here, the results, using ABAQUS/Explicit finite element code, are compared with fracture limit curve (FLC) in order to predict and optimize the press formability by changing parameters of tool radius and tool down-step according to the orthogonal array of Taguchi's method. Firstly, The CAM simulation is used to create cutter location data (CL data). This data are then calculated, modified and exported to the input file format required by ABAQUS through using MATLAB programming. The FEM results are implemented for negative incremental sheet forming and then investigate by experiment.

• Smart Structures and Systems
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• v.20 no.5
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• pp.595-605
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• 2017

The present article reported the thermal buckling strength of the sandwich shell panel structure and subsequent improvement of the same by embedding shape memory alloy (SMA) fibre via a general higher-order mathematical model in conjunction with finite element method. The geometrical distortion of the panel structure due to the temperature is included using Green-Lagrange strain-displacement relations. In addition, the material nonlinearity of SMA fibre due to the elevated thermal environment also incorporated in the current analysis through the marching technique. The final form of the equilibrium equation is obtained by minimising the total potential energy functional and solved computationally with the help of an original MATLAB code. The convergence and the accuracy of the developed model are demonstrated by solving similar kind of published numerical examples including the necessary input parameter. After the necessary establishment of the newly developed numerical solution, the model is extended further to examine the effect of the different structural parameters (side-to-thickness ratios, curvature ratios, core-to-face thickness ratios, volume fractions of SMA fibre and end conditions) on the buckling strength of the SMA embedded sandwich composite shell panel including the different geometrical configurations.

• International Journal of Naval Architecture and Ocean Engineering
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• v.7 no.2
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• pp.315-323
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• 2015

The weld scallop has been used for joining T-bars. There are a lot of weld scallops in shipbuilding. It is difficult to perform scallop welding due to the inconvenient welding position. This results in many problems such as porosity, slag inclusion, etc. In this study, a new method is devised to remove weld scallops by incorporating a Ceramic Backing Material (CBM). The weld scallop is removed by an elongation of the v groove. In order to insert a CBM into the groove without a weld scallop, a wedge-shaped CBM is developed. The top side of the developed CBM is similar to the shape of a general back bead. The bottom surface has a saw-toothed shape for cutting at a suitable length. This can be attached to the root side of a face plate using adhesive tape, just like a general CBM. Welding experiments in normal and abnormal conditions are carried out and the possibility of burn-through is examined. This CBM's applicability to shipbuilding is verified.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.9
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• pp.77-84
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• 2004

The attachment of mobile vehicle is necessary for the automated operation on the inclined or vertical walls of steel structures. Since the vehicle requires attaching devices additionally, its overall efficiency can be reduced by the devices. Therefore, external shapes of mobile vehicles have to be researched to give the effective movement on the vertical face. For the design of mobile vehicle, the guideline has been derived from the modeling of wall-climbing, so that the vehicle should have a specific external shape for vertical movement due to the gravitational force. Hence, some adequate arrangement of attaching device to the mobile vehicle has been presented for the effective movement. In the experiments with four permanent magnetic wheels, a plausible result was achieved as a vertical attaching force of 185.2(N), a friction force of 153.8(N) and a curvature radius of 1.4m. The mobile vehicle should be modified according to the proposed design guideline, and then it could be applied to a specific operation as an appropriate external shape. Also, Further research is recommended on an optimal posture and a moving method in a specific application, as the attaching force of the vehicle can be affected by its posture.

• The Korean Journal of Malacology
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• v.9 no.1
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• pp.46-62
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• 1993

Six species of freshx\water Unionidae mussels in Korea, Anodonta arcaeformis flavotincta, A. woodiana, Unio douglasiae, U. douglasiae sinuloatus, Lamprotula gottschei, Lanceolaria acorohyncha were compared in regard to the various taxonomical characteristics of ultra structures of shells and glochidia. The results obtained in this study are summarized as follows;the orter demibranchs of all the females of six species have served as marsupial(gravid)pouch. However, all the foru demibranchs were used as the marsupium in some female individuals of L. gottschei. The glochidia of A. arcaeformis flavotincta, A. woodiana and L. gottschei were separated one by one with the mucous strings and U. douglasiae sinuolatus were round-subtriangular in shape, and those of L. gottschei were subelliptical in shape. Each of the glochidial shell valves of six species had a hook studded with many spines on the superior face on valve. The glochidial shell valve had two or three rows of large spines; A. arcaeformis flavotincta, A. woodiana, and L. gottschei had two rows and three rows in U. douglasiae, U. douglasiae sinuolatus, and L. acrorhyncha. The numbers of sensory hairs of A. arcaeformis flavotincta and A. woodiana were all eight, those of U. douglasiae, U. douglasiae sinuolatus and L. acrorhyncha were six. and that of L. gottschei was four. The external and internal surfaces of the glochidial shell valves of A. A. arcadformis flavotincta, A. woodiana, and L. gottschei had foveolate and psilate in U. douglaseae, U. douglasiae sinuolatus and L. acrorhyncha.

• Clean Technology
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• v.26 no.4
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• pp.251-256
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• 2020

The biocompatibility and plasmonic properties of Au nanoparticles make them useful for photothermal therapy, drug delivery, imaging, and many other fields. This study demonstrated a novel, facile, economic, and green synthetic method to produce gold nanoparticles. Gold nanoparticles (AuNPs) with spherical and triangular shapes were effectively synthesized using only Schisandra chenesis fruit extract as the capping and reducing agent. The shape of the AuNPs could be engineered simply by adjusting the molar concentration of HAuCl4 in the reaction mixture. The as-synthesized AuNPs were characterized using UV-VIS spectroscopy, transmission electron microscopy (TEM), X-ray diffraction (XRD), dynamic light scattering (DLS), and energy dispersive X-ray analysis (EDXA). This study revealed that by using the HAuCl4 concentration in the AuNP synthesis, the shape and size of the AuNPs could be controlled by the concentration of HAuCl4 and Schisandra chinensis fruit extract as a surfactant. The as-synthesized AuNPs samples had sufficient colloidal stability without noticeable aggregation and showed the predominant growth of the (111) plane of face-centered cubic gold during the crystal growth. The catalytic efficiency of the AuNPs synthesized using Schisandra chenesis fruit extract was examined by monitoring the catalytic reduction of 4-nitrophenol to 4-aminophenol using Ultraviolet-visible spectroscopy (UV-Vis spectroscopy). The synthesized AuNPs showed good catalytic activity to reduce 4-nitrophenol to 4-aminophenol, revealing their practical usefulness.

• Journal of Ocean Engineering and Technology
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• v.38 no.2
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• pp.74-85
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• 2024

Offshore wind turbines are supported by various foundations, each with its considerations in design and construction. Gravity, monopile, and suction bucket foundations encounter geotechnical issues, while jacket and tripod foundations face fatigue problems. Considering this, a gravity foundation based on a steel skirt was developed, and a monopile foundation was analyzed for Pile-Soil Interaction using the p-y curve and 3D finite element method (3D FEM). In addition, for suction bucket foundations, the effects of lateral and vertical loads were analyzed using 3D FEM and centrifuge tests. Fatigue analysis for jacket and tripod foundations was conducted using a hotspot stress approach. Some hybrid foundations and shape optimization techniques that change the shape to complement the problems of each foundation described above were assessed. Hybrid foundations could increase lateral resistance compared to existing foundations because of the combined appendages, and optimization techniques could reduce costs by maximizing the efficiency of the structure or by reducing costs and weight. This paper presents the characteristics and research directions of the foundation through various studies on the foundation. In addition, the optimal design method is presented by explaining the problems of the foundation and suggesting ways to supplement them.

• The Research Journal of the Costume Culture
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• v.8 no.3
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• pp.460-476
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• 2000

The purpose of this study was, accordingly, to examine male college student's general body consciousness and their actual condition of wearing clothing, as it's assumed that clothing, which everyone must always wear, might be effective in making up for the physical defect. The findings of this study were as follows : 1. Male College Students'Body Consciousness : They expressed some dissatisfaction with their own body, and they were most discontented with their height, among their bodies. They thought of the western-style shape as an ideal one, as what's considered by them to be ideal was thinner a little than them, being taller with wider shoulder, longer legs, smaller and white face. 2. Male College Students'Characteristics of Clothing Purchasing Behavior : In purchasing clothing, male college students were slightly sensitive about the physical part with which they wasn't satisfied. The clothing pattern preferred by them was an abstract one, and their favorite color was white or black. The greatest number of them put most emphasis on design in buying clothing, and they purchased clothing mainly at special fashion shop. On the whole, they showed an affirmative response toward wearing Korean costume, and they also had a positive opinion about the purchase of reformed Korean dress for everyday life. 3. Male College Students'Characteristics of Wearing Clothing : They appeared not to consider making up for physical weakness. Male college students favored aloha shirt and trousers when they went out. Male college students purchase clothing in consideration of individual, manly, classical, tender, or comfortable factors. 4. Relationship of Body Consciousness to Wearing Behavior : The degree to which they considered covering up physical weakness in wearing clothing was examined, by dividing them into two groups : one was a group that thought their own shape normal, and the other was a group that didn't think of their own shape as normal. As a result, both groups appeared not to consider covering up physical weakness.