• Journal of the Korean Society for Heat Treatment
• /
• v.13 no.4
• /
• pp.253-258
• /
• 2000

The present study aimed to develop the TRIP(transformation induced plasticity) aided high strength low carbon steel sheets using reverse transformation process. The cold-rolled 0.14C-6.5Mn steel was reverse-transformed by slow heating to intercritical temperature region and air cooling to room temperature. An excellant combination of tensile strength and elongation of $98.3kgf/mm^2$ and 44.4% appears. This combination comes from TRIP phenomena of retained austenite during deformation. The stability of retained austenite Is very Important for the good ductility and it depends on diffusion of carbon and manganese during reverse transformation. The air cooling after holding at intercritical temperature retards the formation of pearlite and provides the carbon enrichment in retained austenite, resulting the increase of elongation in cold-roiled TRIP steel.

• Korean Journal of Plant Resources
• /
• v.28 no.3
• /
• pp.357-362
• /
• 2015

Carbohydrate sources are one of important factors associated with macro- and micro nutrients and phytohormones in vitro culture medium for shoot growth. The optimal carbohydrates for eight species of the genus Prunus which are economically important fruit crop was evaluated at the initiation and elongation stages. All carbohydrate seemed utilized for the bud break and leaf growth at the early stage of culture. However, shoot elongation and fresh weight of species tested were superior in the medium containing 90 mM of fructose or glucose rather than sucrose. There was no difference between glucose and fructose. Adventitious shoots from the axillary buds were induced in most species but no significant differences were observed except for two species (P. salicina ‘Shiro’ and P. tomentosa). These result demonstrated that glucose and fructose were suitable carbohydrate sources for diverse Prunus species than sucrose, although the response to the carbohydrates in the medium were slightly different in the species.

• Journal of Plant Biology
• /
• v.37 no.3
• /
• pp.325-332
• /
• 1994

The effects of polyamines on the activities of elongation factors EF-1 and EF-2, phenylalanyl-tRNA synthetase, and tRNA were investigated. The activities of EF-1 and EF-2 were mostly stimulated by spermidine among three kinds of polyamines. The activities of EF-1 and EF-2 were investigated in the presence of spermidine by 230 and 181%, respectively. The activity of phenylalanyl-tRNA synthetase was slightly increased in the presence of polyamines. The effect of spermine on the synthetase was higher than that of the other polyamines. The tRNA activity in the presence fo polyamines was increased by 206% with spermidine, by 144% with spermine, and by 114% with putrescine. According to these results, it is concluded that polyamines in higher plants stimulate the protein biosynthesis by promoting the activities of elongation factors EF-1 and EF-2, aminoacyl-tRNA synthetases, and tRNAs, but the effects of polyamines on the various components for protein biosynthesis are different in according to the kind of polyamines.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2002.10a
• /
• pp.435-442
• /
• 2002

Fluid Confirmation Tests(FCT) on 1500 ground Anchors install in weathered rock were carried out to investigate upper and lower limit of elastic elongation, frictional resistant of fixed anchor body, mobilized angle between anchor body and soil. All the measured data were analysed and compared with theoretical equations. The frictional angles of diaphragm wall and anchorage system in weathered rock showed nonlinear curve between upper and lower limit of standard elongation. The FCT results indicated that the frictional resistant angles increased with higher values of surcharge load. The quality assurance on the fixed anchor location was investigated by means of measuring elastic elongation during the FCT, and comparing these with theoretical design length, the quality of anchors in this particular site found to be above average standard. The results of this research works with provide valuable guide line on quality assurance of anchors system as well as resonable prediction of friction resistance between the fixed anchor body and the weathered rock.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.26 no.1
• /
• pp.33-37
• /
• 2013

The properties of LTCC green sheets formed by the MLS-22 powder of NEG Inc. were investigated for acrylic binders with different PVB and Tg in the variation of temperature. The elongation of the green sheets showed large variation depending on the temperature, and was rapidly decreased near the Tg of the sheets. With the increase of the ratio of plasticizer/binder (P/B), large elongation of the sheets was observed due to the decrease of the Tg. In the stacking process of the multilayer ceramic, the optimal control of the temperature is highly required depending on the Tg of the binder and the ratio of P/Buniform coating.

• Korean Journal of Materials Research
• /
• v.24 no.1
• /
• pp.1-5
• /
• 2014

This study is experimentally investigated whether or not a relationship exists between the mechanical properties and damping capacity of cold-rolled 316 L stainless steel. Deformation-induced martensite was formed with surface relief and directionality. With the increasing degree of deformation, the volume fraction of ${\varepsilon}$-martensite increased, and then decreased, while ${\alpha}^{\prime}$-martensite increased rapidly. With an increasing degree of deformation, tensile strength was increased, and elongation was decreased; however, damping capacity was increased, and then decreased. Tensile strength and elongation were affected in the ${\alpha}^{\prime}$-martensite; hence, damping capacity was influenced greatly by ${\varepsilon}$-martensite. Thus, there was no proportional relationship between strength, elongation, and damping capacity.

• Journal of Plant Biology
• /
• v.37 no.4
• /
• pp.397-402
• /
• 1994

Possible roles of polyamines in the inhibition of cell elongation in Ranunculus petioles were investigated. Exogenously apoplied polyamines greatly inhibited the auxin-induced petiole growth, while treatment of the tissue with $\alpha$-difluoromethylarginine, the inhibitor of putrescine biosynthesis, further enhanced the growth in the presence of IAA. Inhibitory effect of spermine can also be apparent for fusicoccin-induced elongation, but not for growth induced by a low pH. Spermine also suppressed the ethylene-enhanced growth in the presence of auxin. Using computer-based video digitizer system, the inhibitory effects of spermine on petiole growth were kinetically analyzed. Auxin-induced growth was characterized by an initial and transient growth with a highly elevated rate followed by a steady growth with a slightly reduced rate. Spermine treatment was found to shorten the duration of the initial phase of growth, and to reduce the rates of both the initial and steady growth as well. The latent period for auxin induction was not affected by spermine.

• Annual Conference of KIPS
• /
• 2001.10a
• /
• pp.631-634
• /
• 2001

가상 현실이나 게임 제작 분야에서는 움지임에 따른 변형을 실시간으로 처리하는 것이 요구되고 있다. 변형 처리를 위한 일반적인 모델은 질량-스프링(mass-spring) 방법을 이용한 것으로, 그 구현이 쉽고 처리 속도가 빨라 대화형 시스템(interactive system)에서 실시간 처리를 위한 모델로 주목되고 있다. 반면에, 이 모델은 외부의 제어에 대하여 super-elastic한 문제를 내포하여 그 적용이 제한되어 있다. 본 논문에서는 스프링 모델의 근본적인 문제인 super-elastic 문제를 극복하기 위한 근사 방법을 제안한다. 제안하는 방법은 하이브리드 접근 방식으로, 이산 점 사이의 내부 힘들을 선처리(pre-processing)하여 elastic한 성분을 나누어 처리한다. 선처리 과정에서는 변형 물체의 물리적 속성에 따라 늘어나는(elongation) 성분과 굽어지는(bending) 성분을 따로 처리함으로써, 극심히 늘어나는(super-elongation) 문제를 극소화할 수 있다. 본 논문의 결과로는 빈번한 제어에 대응되는 움직임을 빠르게 생성할 수 있음을 보이며, 안정적이면서 그럴 듯한 움직임을 생성할 수 있음을 보인다.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.13 no.11
• /
• pp.938-942
• /
• 2000

Radiation effects on dielectric properties of low density polyethylene(LDPE) were investigated using the various measurements of FT-IR, gel content and elongation at break. FT-IR spectra showed that polar groups were comprised in LDPE due to radiation treatment. It was also confirmed that the formation of polar groups on LDPE caused the increased dielectric properties such as permittivity and tan $\delta$. However, in this study, any evidence of decreasing permittivity was not found although the morphological change of LDPE could be identified from the increasing gel content and the decreasing elongation.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2000.07a
• /
• pp.169-172
• /
• 2000

In this paper, we evaluated the mechanical and dielectric properties of LDPE depend on $Co_{60}$${\gamma}$-irradiation doses. The chemical analyses for FT-IR, gel content, the mechanical properties for elongation at break and the dielectric parameters for permittivity, tan$\delta$ were discussed as a function of irradiation doses. Test result presented that elongation at break of irradiated LDPE was inversely proportional to gel content. For dielectric analyses, permittivity showed a salient characteristic for various irradiation doses, it was related to polar groups caused radiation degradation and tan$\delta$ of irradiated LDPE increased with irradiation doses.