• Journal of Mechanical Science and Technology
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• v.15 no.8
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• pp.1079-1089
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• 2001

This paper proposes J and CTOD estimation schemes applied to fracture toughness testing, covering typical homogeneous and bi-material specimens. Recommendations are based on the plastic limit analysis (either slip line field or finite element limit analyses), assuming the rigid plastic material behavior. The main outcome of the present study is that the J and CTOD estimation schemes (both codified and non-codified), recommended for homogeneous specimens, can be equally used for bi-material specimens with interface cracks. The effect of yield strength mismatch in bi-material specimens on the J-integral CTOD is discussed.

• Proceedings of the KSR Conference
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• 2005.05a
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• pp.556-561
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• 2005

The steel shows plastic deformation after the yield point exceeds. The plastic deformation due to overloads occurs at the interior support of a continuous bridge. The plastic deformation is concentrated at the interior support and the permanence deformation at the interior support remains after loads apply. Because local yielding causes the positive moment at the interior support, it is called 'auto-moment'. Auto-moment redistributes the elastic moment. Because of redistribution, auto-moment decreases the negative moment at the interior support of a continuous bridge. In this paper, the plastic rotation is evaluated using the moment-rotation curve proposed by Schalling and Beam-line method. Moreover, auto-moment is derived from the experiment curve.

• Journal of Microbiology and Biotechnology
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• v.5 no.1
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• pp.31-35
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• 1995

An antitumor antibiotic named YS-1649 was isolated from the culture filtrate of a newly isolated fungus identified as Penicillium sp.. The fermentation yield reached about 40 mg per liter of the broth. YS-1649, a $\gamma$-Iactone - structured antibiotic, has the molecular fomular of $C_7H_6O_4$, Its structure was determined to be patulin by spectral analysis. It is active against some bacteria and showed cytotoxic effect on the proliferation of human breast cancer cell line, MCF-7, at concentrations of more than 0.048 $mu g/ml$. This compound also showed strong cytotoxic effect on the proliferation of human cancer cell lines, A549 and ACHN.

• ETRI Journal
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• v.31 no.6
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• pp.741-748
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• 2009

We present an analysis of microstrip coupled lines (MCLs) used to improve the stability of a 60 GHz narrowband amplifier. The circuit has a 4-stage structure implementing MCLs instead of metal-insulator-metal (MIM) capacitors for the unconditional stability of the amplifier and yield enhancement. The stability parameter, U, is used to compare the stability of MCLs with that of MIM capacitors. Experimental results show that MCLs are more stable than MIM capacitors with the same capacitances as MCLs because the parasitic parallel resistances of MCLs are lower than those of MIM capacitors. Moreover, the bandwidth of an amplifier using MCLs is narrower than one using MIM capacitors because the parasitic series inductances of MCLs are higher than those of MIM capacitors.

• Proceedings of the IEEK Conference
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• 2003.11c
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• pp.60-63
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• 2003

This paper describes the design and the simulation of a V-band single pole double throw (SPDT) FET switch fur millimeter-wave applications using drain impedance transformation network with CPW transmission line. The designed switch has about 10% bandwidth at 60GHz. Insertion loss is better than 3dB fur the ON state and Isolation is larger than 30dB fer the OFF state. The maximum isolation is 43.4dB at 60GHz with input power of 10dBm. The yield analysis is done considering the effects of pHEMT variations.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.101-101
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• 2017

This study was carried out to improve yield potential of Tongil type rice variety based on QTLs analysis associated with yield component using a total of 386 rice recombinant inbred lines (RILs) derived from a cross between Tongil type high yield variety "Hanareum2" and Japonica variety "Unkwang". 384 SNP markers were used, and 241 of them (62.6%) were polymorphic between Hanareum2 and Unkwang. One hundred forty-four QTLs in 11 traits, such as heading days, were detected. Most of them were 21 QTLs associated with 1000 grain weight and the least was 8 QTLs associated with panicle number. The QTL, qDTH3-2 associated with days to heading was identified to delay heading date for 2.4~2.6 day. Eleven QTLs were associated with culm length. The QTL, qCL1-2 on chromosome 1, was identified to decrease culm length. A total of 16 QTLs were detected for panicle length. Three QTLs, qPL3, qPL6, and qPL7-1 were increased panicle length. Seven QTLs related to panicle number except qPN7 were increased the number of panicle. Four QTLs related to grain number per panicle, qGNP2-1, qGNP6, and qGNP7, were increased the number of grains. Three QTLs associated with grain filling rate, qGFR1, qGFR2-2, and qGFR7-1 were increased grain filling rate. Twelve QTLs associated with 1,000 grain weight. were increased the grain weight. Fourteen QTLs were identified associated with grain length. 10 QTLs, such as qGL1-1, were increasing grain. Fifteen QTLs associated with grain width were detected. The 8 QTLs, such as qGW1-1, were elongated grain width. Seventeen QTLs were associated with grain thickness, and ten QTLs of them were increased grain thickness. We need further study to develop introgression lines of each QTL to improve yield potential of Tongil type rice variety.

• Journal of the Microelectronics and Packaging Society
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• v.23 no.2
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• pp.79-84
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• 2016

A flexible electronic device deformed by external force causes the failure of a semiconductor die. Even without failure, the repeated elastic deformation changes carrier mobility in the channel and increases resistivity in the interconnection, which causes malfunction of the integrated circuits. Therefore it is desirable that a semiconductor die be placed on a neutral line where the mechanical stress is zero. In the present study, we investigated the effects of design factors on the position of neutral line by finite element analysis (FEA), and expected the possible failure behavior in a flexible face-down packaging system assuming flip-chip bonding of a silicon die. The thickness and material of the flexible substrate and the thickness of a silicon die were considered as design factors. The thickness of a flexible substrate was the most important factor for controlling the position of the neutral line. A three-dimensional FEA result showed that the von Mises stress higher than yield stress would be applied to copper bumps between a silicon die and a flexible substrate. Finally, we suggested a designing strategy for reducing the stress of a silicon die and copper bumps of a flexible face-down packaging system.

• Journal of Animal Science and Technology
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• v.47 no.3
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• pp.355-362
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• 2005

This study was carried out to obtain basic information on variety selection for the utilization of whole crop rices(WCR) at National Institute of Crop Science, RDA, in 2004. Fifteen varieties and elite line were evaluated on feed value such as dry matter yield(DMY), crude protein( CP), acid detergent fiber(ADF), neutral detergent fiber(NDF) and total digestible nutrients(TDN). The dry matter yields were ranged from 13.23 to 17.83 ton per ha, the highest yielding varieties were Sobibyeo(l6.98ton / ha) in Japonica type, SR22060 (17.83 ton / ha) in New plant type, Hangangchalbyeo(I7.66 ton / ha) in Tongil type. Suweon 468 showed the highest value in the RFV and TDN content among the varieties, and Suweon 468, Suweon 498, Suweon 490 and SR22058 were chosen to have the high feed values through cluster analysis. The dry weight(grain) was found to be positively related with percent of the ripened grain, 1,000 grain weight and CPo TDN content was found to be positively related with CP, but negatively related with NDF and ADF. RFV was found to be negatively related with plant height, NDF and ADF. The promising rice varieties for WCR were Suweon 468, Suweon 498, Suweon 490 and SR22058 on the basis of CP, TDN and DMY.

• Journal of Korean Society of Steel Construction
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• v.29 no.4
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• pp.281-289
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• 2017

The current AASHTO LRFD and Eurocode 3 specifications have been found to underestimate the flexural strength of longitudinally reinforced plate girders. This is because the web-flange interaction is not considered appropriately when a web is reinforced. The buckling strength of compression flange increases due to the improved rotational restraint to the compression flange. Also, the compression flange and the longitudinal stiffener could constrain the web rotation, so that a certain area of the web reaches yield strength. In this study, a model for evaluating the flexural strength is proposed for plate girders reinforced with one line of longitudinal stiffeners, considering the increase of the buckling strength of the compression flange and the actual stress distribution of the web. The flexural strengths of the conventional steel(SM490) and the high-strength steel(HSB800) plate girders were evaluated from the nonlinear analysis and the applicability of the proposed model was analyzed.

• Journal of the Microelectronics and Packaging Society
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• v.20 no.4
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• pp.47-52
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• 2013

Gold wire has long been used as a proven method of connecting a silicon die to a substrate in wide variety of package types, delivering high yield and productivity. However, with the high price of gold, the semiconductor packaging industry has been implementing an alternate wire material. These materials may include silver (Ag) or copper (Cu) alloys as an alternative to save material cost and maintain electrical performance. This paper will analyze and compare the electrical characteristics of several wire types. For the study, typical 0.6 mil, 0.8 mil and 1.0 mil diameter wires were selected from various alloy types (2N gold, Palladium (Pd) coated/doped copper, 88% and 96% silver) as well as respective pure metallic wires for comparison. Each wire model was validated by comparing it to electromagnetic simulation results and measurement data. Measurements from the implemented test boards were done using a vector network analyzer (VNA) and probe station setup. The test board layout consisted of three parts: 1. Analysis of the diameter, length and material characteristic of each wire; 2. Comparison between a microstrip line and the wire to microstrip line transition; and 3. Analysis of the wire's cross-talk. These areas will be discussed in detail along with all the extracted results from each type the wire.