• Korean Journal of Ichthyology
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• v.6 no.2
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• pp.206-221
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• 1994

Morphometrical data for diploid and induced triploid cherry salmon, Oncorhynchus masou were analyzed prior to the spawning season to compare their commercial values. The following traits were measured with the diploids and induced triploids : ungutted and gutted body weight; body length; dressing percentage; condition factor; gonad weight and gonad index; belly thickness; viscera weight; viscera index; body circumference at the pelvic, dorsal and anal fins; area of the cross sections at the pelvic and dorsal fins; two belly thickness traits measured on each cross section; total height, height and width of each cross section; three body shape traits; and nine cross section shape traits. Body length and body weight of diploids were larger than those of induced triploids and dressing percentage, gonad weight, gonad index, viscera index, and liver index were also larger in diploids. However, induced triploids showed higher values in one belly thickness trait and some section shapes than diploids. Differences in body traits were due to the sterility of induced triploids. Therefore, induced triploid cherry salmon appears to have greater potentials for the commercial values than their diploids.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.187-199
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• 2011

The main objective of this study was investigation of natural gas flames in a lean premixed swirl-stabilized dump combustor with an attention focused on the effect of the various fuel-air mixing section geometry on the combustion instability characteristics. The multi-channel dynamic pressure transducers were located on the combustor and inlet mixing section region to observe combustion pressure oscillation and difference phase at each dynamic pressure measurement results. Dynamic pressures were also measured to investigate characteristics of combustion at the same time. The combustor and mixing section length was varied in order to have different acoustic resonance characteristics from 800 to 1800 mm in combustor and 470, 550, 870 mm in mixing section. We observed two dominant instability frequencies in this study. Lower frequencies were obtained at lower equivalence ratio region and it was associated with a fundamental longitudinal mode of combustor length. Higher frequencies were observed in higher equivalence ratio conditions. It was related to secondary longitudinal mode of coupled with the combustor and mixing section. In this instability characteristics, pressure oscillation of mixing section part was larger than pressure oscillation of combustor. As a result, combustion instability was strongly affected by acoustic characteristics of combustor and mixing section geometry.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2007.05a
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• pp.417-420
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• 2007

Micro parts are usually used of producing by micro-electro-mechanical systems(MEMS). In this paper, we present some fundamental results concerning on the MEMS, extrusion condition on the micro forming characteristics and new micro forward extrusion machine has been developed. In the first step, we manufactured micro dies in two kinds of sections. One is a circle section, another is a cross section. The process for fabricating micro dies combines a deep UV-lithography, anisotropic etching techniques and metal electroplating with bulk silicon based on Ni with a thickness of $50{\mu}m$. The outer diameter of Ni-micro dies is 3mm and the diameter of extrusion section is $270{\mu}m$ for a cross section, $500{\mu}m$ for a circle section. The low linear density polyethylene(LLEPD) in the shape of a pellet has been used of micro extrusion. The billet was placed in a container manufactured by electric discharge machining and extruded through the micro die by a piezoelectric actuator. The micro extrusion has succeeded in a forming such micro parts as micro bars, micro cross shafts.

• Fashion & Textile Research Journal
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• v.9 no.6
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• pp.651-657
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• 2007

This study was carried out to analyse body configuration and to observe any space between skin and foundation. A special 3D scanner was used to analyze this foundation. Experimental foundations were brassiere, girdle, and all-in-one. Four subjects volunteered, each subject was scanned while wearing foundation and not wearing foundation. Body shape variations were analyzed with an Auto CAD and ScanWax program which analyzes cross section of the skin surface to look for any changes. Height was increased all parts of body, circumference was increased in breast and bust while wearing the foundation. The hip thickness was not increased with wearing the foundation. Therefore this foundation makes people have a different appearance due to unexpected body shape variations. The effects of this foundation should be classified by observing height, circumference, and thickness changes in the body.

• Transactions of Materials Processing
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• v.19 no.1
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• pp.32-37
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• 2010

Hydroforming has attracted a great deal of attention in the manufacturing industries for vehicles and transportation systems. Hydroforming technology contributes to weight reduction, increased strength, improved quality and reduced tooling cost. Hydroformed automotive parts used as structure components in vehichle body frame often have to be structurally joined at some point. Therefore it is useful if the hydroformed automotive parts can be given a localized attachment flange. For a given flange shape, a parting plane for the dies is established relative to which the various surfaces of the flange shape, in cross section, have no significant reverse curvature. In this study, hydroforming process for flange forming was proposed. FE analysis to form flanged circular shape and flanged rectangular shape was preformed with Dynaform 5.5. To accomplish successful hydroforming process design, thorough investigation on proper combination of process parameters such as tool geometry and hydraulic pressure has been performed and optimized. The results show that flanged automotive parts can be successfully produced with tube hydroforming.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.1 s.244
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• pp.76-83
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• 2006

This paper addresses the method for the shape design sensitivity analysis of the buckling load in the continuous elastic body. The sensitivity formula for critical load is analytically derived and expressed in terms of shape variation, based on the continuum formulation of the stability problem. Though the buckling problem is more efficiently solved by the structural elements such as beam and shell, the elastic solids are considered in this paper because the solid elements can be used in general for any kind of structures whether they are thick or thin. The initial stress and buckling analysis is carried out by the commercial analysis code ANSYS. The sensitivity is computed by using the mathematical package MATLAB using the results of ANSYS. Several problems including straight and curved beams under compressive load, ring under pressure load, thin-walled section and bottle shaped column are chosen to illustrate the efficiency of the presented method.

• International Journal of Precision Engineering and Manufacturing
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• v.1 no.1
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• pp.146-151
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• 2000

The importance of shape reconstruction is increasing in many areas such as RPD(Rapid Product Development) and reverse engineering. Typical data in these areas are mainly classified as the shape data measured by a laser scanner and the data extracted from the CT image. The goal of this research is to realize three-dimensional shape construction by showing a possible way to analyze input image data and reconstruct the original shape. Two main steps of the reconstructing process are obtaining cross-section data from image processing and linking loops between one slice and the next. Objects reconstructed in this way are compared with other objects using a laser scanner and modelled by commercially available software. The technique is expected to be used in reverse engineering applications and the object modeling with automated process.

• Computers and Concrete
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• v.4 no.4
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• pp.317-330
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• 2007

Steel reinforced concrete is perhaps the most versatile and widely used construction material. The versatility is attributed to mouldability of concrete to any conceivable shape. The inherent property of cracking of concrete is the reason for its low tensile strength and hence the design approach of RCC sections in flexure adopts the cracked section theory where in concrete in tension zone is ignored. Means, modes and methods of exploitation of concrete strength by conceiving shapes other than rectangular whereby ineffective concrete in tension zone is reduced and incorporated in compression zone where it is effective needs consideration. Shape optimization of beams is attempted in this analytical investigation employing Sequential Unconstrained Minimization Technique (SUMT). The results clearly show that trapezoidal beams happen to be less costlier than their rectangular counterparts, their usage needs serious reconsideration by the designers.

• The KSFM Journal of Fluid Machinery
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• v.3 no.4 s.9
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• pp.15-21
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• 2000

An anemometer employing the bulk PTC thermistor as the sensing element is investigated in this study. The numerical and experimental works are carried out to improve the sensitivity problem of the element by focusing fluid dynamics point of view. The typical shape of the sensing element has been used as a rectangular type, but this shape has a sensitivity problem because of flow separations on the sharp edge when the flow direction is different from that of the sensing element. In order to reduce the reading error, the installer has to be very careful about the flow direction. The reading error fluctuation by time as well as the sensitivity problem can be improved considerably through this study. It can be concluded that the small change of the sensor shape can improve the performance of the flow sensor.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1705-1708
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• 2003

The purpose of this study is to investigate the manufacturing technique on the U type Draw-Bending of inner grooved tube. This bending process make the U shape tube by Hair Pin Bending machine. The U type tube requires the quality of product that satisfy sufficient conditions for a heat exchanger. The mandrel components act the important roles that prevent wrinkles and keep the shape of cross section of bended tube at bending process. We performed the FEM simulation using LS-DYNA software and the bending test of inner groove tube and then, compared bending simulation with bending test results about mandrel ball diameter, mandrel position and optimal clearance between mandrel and tube.