• Transactions of the Korean Society of Automotive Engineers
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• v.19 no.2
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• pp.117-124
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• 2011

Valve springs with non-circular cross-section are widely used in automotive engines. Because of the reduced height, the oval cross-section provides some merits in its install height and stress distribution. This paper introduces a new method to generate optimal shape of the non-circular cross-section. For given width and height, arbitrary shape of the cross-section are described using the Hermite spline curves. Cross-section area and maximum stress level are chosen as performance indices, and nonlinear optimization problems are formulated with inequality constraints. Compared to a production spring wire, cross-section area can be reduced about 2.4 [%] without increasing maximum stress level. In addition, the other approach gives an optimum cross-section which reduces maximum stress level of 2.0 [%] without increasing cross-section area.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.9 no.3
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• pp.48-54
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• 2000

In this study the characteristics of chip formation of the cold drawn Bi-S free machining steels were assessed. And for comparison those of the cold drawn Pb-S free machining steel the hot rolled low carbon steel which has MnS as free machining inclusions and the conventional steels were also investigated. During chip formation the cold drawn free machining steels show relatively little change in thickness and width of chip compare to those of the conventional carbon steels. And a single parameter which indicates the degree of deformation during chip formation chip cross-section area ratio is introduced. The chip cross-section area ratio is defined as chip cross-section area is divided by undeformed chip cross-section area. The variational patters of the chip cross-section area ratio of the materials cut are similar to those of the shear strain values. The shear stress however seems to be dependent on the carbon content of the materials. The cold drawn Bi-S and Pb-S steels show nearly the same chip forming behaviors and the energy consumed during chip formation is almost same. A low carbon steel without free machining aids shows poor chip breakability due to its high ductility. By introducing a small amount of free machining inclusions such as MnS Bi, Pb or merely increasing carbon content the chip breakability improves significantly.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1999.10a
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• pp.351-356
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• 1999

In this study, the characteristics of chip formation of the cold drawn Bi-S free machining steels were assessed. And for comparison, those of the cold drawn Pb-S free machining steel, the hot rolled low carbon steel which has MnS as free machining inclusions and the conventional steels were also investigated. During chip formation, the cold drawn free machining steels show relatively little change in thickness and width of chip compare to those of the conventional carbon steels. And a single parameter which indicates the degree of deformation during chip formation, 'chip cross-section area ratio' is introduced. The chip cross-section area. The variational patterns of cross-section area is divided by undeformed chip cross-section area. The variational patterns of the chip cross-section area ratio of the materials cut are similar to those of the shear strain values. The shear stress, however, seems to be dependent on the carbon content of the materials. The cold drawn BiS and Pb-S steels show nearly the same chip forming behaviors and the energy consumed during chip formation is almost same. A low carbon steel without free machining aids shows poor chip breakability due to its high ductility. By introducing a small amount of non-metallic inclusions such as MnS, Bi, Pb or merely increasing carbon content the chip breakability improves significantly.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2007.05a
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• pp.71-74
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• 2007

Substitution of the stacked antenna for the normally pressed antenna in the mobile phone was tried for the purpose of decreasing its size. However, reduced size resulted in the difficulties obtaining the targeted characteristics with the bandwidth over 70MHz. The cross-section of the vias in the low temperature co-firing ceramics process was studied to find out effects on the bandwidth characteristics. Circular and rectangular cross-section of the via beneath different types of antenna patterns were simulated. Better bandwidth characteristics were acquired for the larger diameter of the circular section and for the rectangular section as the cross-section area increased. From the viewpoint of the shape of the cross-section, rectangular area showed better characteristics than the circular area with the same longest length in the cross-section.

• Fashion & Textile Research Journal
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• v.2 no.4
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• pp.360-365
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• 2000

This research is the trial for the computation of the ease-rate for the bodice pattern. The result of the analysis about the cross section figures of garment space by using a 3-D measuring instrument is that: The garment space of each bodice by each body size is definite. In the figure of cross section of the basic lines, an area of cross section of garment space and length of cross section of garment space are not increased in proportion to an area of cross section of the body. The ease rate is the same no matter that flat-rate of the body is same or different. The ease-rate is computed by length of cross section of garment space that is in proportion to the radius of the body.

• Applied Microscopy
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• v.47 no.2
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• pp.77-83
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• 2017

Drastic development of ubiquitous devices requires more advanced batteries with high specific capacitance and high rate capability. Large-area microstructure characterization across the stacks of cathode, electrolyte and anode might reveal the origin of the instability or degradation of batteries upon cycling charge. In this study, sample preparation methods to observe the cross-section view of the electrodes for battery in SEM and several imaging tips are reviewed. For an accurate evaluation of the microstructure, ion milling which flats the surface uniformly is recommended. Pros and cons of cross-section polishing (CP) with Ar ion and focused ion beam (FIB) with Ga ion were compared. Additionally, a modified but new cross-section milling technique utilizing precision ion polishing system (PIPS) which can be an alternative method of CP is developed. This simple approach will make the researchers have more chances to prepare decent large-area cross-section electrode for batteries.

• Fibers and Polymers
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• v.6 no.1
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• pp.82-88
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• 2005

We have investigated the luster of modified cross-sectional fiber fabrics as one of the essential quality estimates for clothing development. We have confirmed an objective evaluation method, and have determined the experimental luster char­acteristics of modified cross-section fibers. The cross-section of the fibers in a fabric affects the appearance of a textile. We used the image analysis method to investigate the luster to determine the critical factors influencing the appearance of modi­fied cross-section fiber fabrics. For similarly structured textiles in a component fabric, clear differences were observed in the fabric weave, density, percentage, and total area of blobs, which is image region. Color played a decisive role in the luster of the textiles, and luster was not significantly influenced by the modified cross-section fabric weave. In addition, the degree of luster did not increase in the order plain to twill to satin for modified cross-sectional fiber fabrics. All the split-type microfi­bers exhibited higher numerical luster values (percentage of pixels, and number and total area of blobs) than sea-island microfibers did. The degree of luster of the modified cross-sectional fiber fabrics was not high at specular reflection angles.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.628-631
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• 2001

Current lead is one of the first proposed devices for the application of High Temperature-Superconductor(HTSC). The current lead provides high current for electrical machine using superconductor from room temperature. Its characteristics that is zero resistance and low heat transfer rate under critical temperature lead to research for the replacement of existing current lead with HTSC. In this paper, we investigated the temperature distributions of stacking type and rod type current lead with each cross-section area and length using Nastran program and compared each temperature distribution. It is obtained from this paper that stacking type current lead has flat temperature gradient and than rod type one and more stable operation as current lead is closely related with its cross-section area and length.

• Proceeding of EDISON Challenge
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• 2015.03a
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• pp.257-262
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• 2015

In this paper, the cross-section properties of thin-walled beam are calculated through KSec2D in consist of Saint-Venant theory. To investigate tendency increasing the thickness, we analysis cross-section using isotropic material. In the asymmetric cross-section, we investigate effect caused cross-section properties accompanied increasing the thickness. The structural properties such as bending stiffness, tosion stiffness per area of each cross-section in three cases is compared through increasing thickness. The warping displacement calculated by KSed2D is modeled by CATIA. In order to show that warping influence the cross-section, the warping shape modeled CATIA is printed 3D printer.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.8
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• pp.1171-1176
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• 1999

The precision and reliability of the Computer Image Analysis technique using a desk top computer for extracting information from carcass cross section scans was evaluated by the repeatability (R) and coefficient of variation (CV) for error variance. The 6th and 7th ribs cross section of carcasses from 55 fattened Japanese Black steers were used. The image analysis was conducted using a desk top computer (Macintosh-Apple Vision 1710 Display) connected to a scanner and an image capture camera. Two software applications, Adobe Photoshop and Mac Scope were used interchangeably. The information extracted and measured were individual muscle area, circumference length, long and short axes lengths, muscle direction; distance between any two muscle centers of gravity; cross section total area, lean, fat, and bone. The information was extracted after the processes of scanning, digitization, masking, muscle separation, and binarization. When using the Computer Image Analysis technique by desk top computer, proper digitization and selection of scanning resolution are very important in order to obtain accurate information. The R-values for muscle area, circumference, long and axes lengths, and direction ranged from 0.95 to 0.99, whereas those of the distance between any two muscle centers of gravity ranged from 0.96 to 0.99, respectively. For the cross section total area, lean, fat, and bone it ranged from 0.83 to 0.99. Excellent repeatability measurements were observed for muscle direction and distance between any two muscle centers of gravity. The results indicate that the Computer Image Analysis technique using a desk top computer for extracting information from carcass cross section is reliable and has high precision.