• International Journal of Automotive Technology
• /
• 제6권3호
• /
• pp.259-268
• /
• 2005

In order to analyze the sheet drawability, the measurement of the plastic strain ratio was carried out for the 5182 aluminum alloy sheets in which were cold rolled without lubrication and subsequent recrystallization annealing. The average plastic strain ratio of the 5182 aluminum sheets was 1.50. It was considered that the higher plastic strain ratio was resulted from the ND//<111> component evolved during rolling and maintained during annealing. The AA5182/polypropylene/AA5182 (AA/PP/AA) sandwich sheets of the 5182 aluminum alloy skin sheet and the polypropylene core sheet with high formability have been developed for application for automotive body panels in future light weight vehicles with significant weight reduction. The AA/PP/AA sandwich sheets were fabricated by the adhesion of the core sheet and the upper and lower skin sheets. The AA/PP/AA sandwich sheet had high plastic strain ratio (1.58), however, the planar anisotropy of the sandwich sheet was little changed after fabrication. The optimum combination of directionality of the upper and lower skin sheets having high plastic strain ratio and low planar anisotropy was calculated theoretically and an advanced process for producing the sandwich sheets with high plastic strain ratio was proposed. The developed sandwich sheets have a high average plastic strain ratio of 1.55 and a low planar anisotropy of 0.17, which was improved more by 3.2 times than that of 5182 aluminum single sheet.

• 한국정보통신학회:학술대회논문집
• /
• 한국정보통신학회 2017년도 춘계학술대회
• /
• pp.375-378
• /
• 2017

전 세계적으로 해운물류 안전 보안체계가 강화됨에 따라 국가물류보안 체계 구축을 위한 해운물류안전 보안 핵심기술 개발이 이루어지고 있다. 또한 미국에서 2018년 시행예정인 컨테이너 사전 100% 전수검사에 대응하기 위한 컨테이너 검색기의 핵심구성 요소인 Array 검출 System의 국산화 개발이 필요하다. 본 논문에서는 현재 해외제품을 대체할 Array 검출 system 중 자체 개발한 Digital Signal Processing Board에 대한 연구를 제안하고자 한다.

• 한국정보통신학회:학술대회논문집
• /
• 한국정보통신학회 2017년도 춘계학술대회
• /
• pp.379-382
• /
• 2017

전 세계적으로 해운물류 안전 보안체계가 강화됨에 따라 국가물류보안 체계 구축을 위한 해운물류안전 보안 핵심기술 개발이 이루어지고 있다. 또한 미국에서 2018년 시행예정인 컨테이너 사전 100% 전수검사에 대응하기 위한 컨테이너 검색기의 핵심구성 요소인 Array 검출 System의 국산화 개발이 필요하다. 본 논문에서는 현재 자체 개발한 Test Digital 신호처리 Board를 가지고 TI-RTOS(Texas Instruments - Real Time Operating System)를 이용하여 개발한 Test Software Program을 제안한다.

• 한국의류산업학회지
• /
• 제17권2호
• /
• pp.287-294
• /
• 2015

This study investigates the physical properties of Murata Vortex Spinning (MVS) blended yarn with yarn count(20's, 30's, 40's) and blend ratio(Polyester 100, Polyester70:Cotton30, Polyester50:Cotton50, Polyester30:Cotton70, and Polyester50:Tencel40:Cotton10). This study evaluated tenacity, elongation, bending rigidity, bending hysteresis, hairiness coefficient, irregularity and twist number. The structure of MVS blended yarn influenced stress, strain, bending rigidity, bending hysteresis and the hairiness coefficient of MVS blended yarn decreased as the yarn count increased. MVS blended yarn consists of core and sheath. The core of MVS blended yarn is composed of a parallel fiber with a wrapping fiber that covers thecore fiber. This special structure of the MVS blended yarn effects the physical properties of the yarn; in addition, the mechanical properties of the component fibers influenced the stress, strain, bending rigidity, bending hysteresis and hairiness coefficient of MVS blended yarn with the blend ratio. Polyester decreases and cotton increases resulted in decreased physical properties. A similar polyester content increased the tencel and physical properties. Appropriate physical properties and a variety of touch expression can be realized through a correct blend ratio.

• 한국의류산업학회지
• /
• 제15권3호
• /
• pp.467-476
• /
• 2013

This study investigates the dyeability and the fastness of flame retardant polyester fabric developed by a thermal bonding with a low melting component of flame retardant bicomponent filament (LMFRPC). The fabrics were prepared with flame retardant polyester filaments (FRP) as warp and blended filaments of FRP and LMFRPC as weft. The LMFRPC have a sheath and a core where the core comprises a flame retardant polyester and the sheath comprises a thermoplastic polyester with a low-melting point. The thermal bonding of fabric was conducted in a pin tenter at $170^{\circ}C$ for 60 seconds. Fabric dyeing was conducted with an infrared dyeing machine at various dyeing temperatures and dyeing times. The dyestuffs used in this study were CI disperse Yellow 54, Red 60 and Blue 56 of E-type dyestuff and Orange 30, Red 167 and Blue 79 of S-type dyestuff. This study investigated the morphology of thermal bonded fabric, dyeability and fastness of dyed fabric. Dyeability increased with an increased dyeing temperature. The thermal bonded area increased with the increased LMFRPC content. The dyeability of S-type dyestuff was higher than E-type dyestuff; in addition, the saturated dyeing time was about 20minutes at $130^{\circ}C$ for E and S-type dyestuff. The fastness to washing and rubbing were excellent at a 4-5 Grade.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2003년도 추계학술대회 논문집 Vol.16
• /
• pp.255-258
• /
• 2003

The hysteresis characteristics of flux-lock reactor, which is an essential component of flux-lock type superconducting fault current limiter (SFCL), was investigated. The hysteresis loss of iron core in flux-lock type SFCL does not happen due to its winding's structure especially in the normal state. From the equivalent circuit for the flux-lock type SFCL and the fault current limiting experiments, the hysteresis curves could be drawn. Through the hysteresis curves together with the fault current level due to the inductance ratio for the 1st and 2nd winding, the increase of the number of turns in the 2nd winding of the flux-lock type SFCL had a role to prevent the iron core from saturation.

• Bulletin of the Korean Chemical Society
• /
• 제16권6호
• /
• pp.547-552
• /
• 1995

As an extension to the Kramers' restricted Hartree-Fock (KRHF) method [J. Comp. Chem., 13, 595 (1992)], we have implemented the Kramers' restricted configuration interaction (KRCI) program in order to calculate excited states as well as the ground state of polyatomic molecules containing heavy atoms. This KRCI is based on determinants composed of the two-component molecular spinors which are generated from KRHF calculations. The Hamiltonian employed in the KRHF and KRCI methods contains most of all the important relativistic effects including spin-orbit terms through the use of relativistic effective core potentials (REP). The present program which is limited to a small configuration space has been tested for a few atoms and molecules. Excitation energies of the group 14 and 16 elements calculated using the present KRCI program are in good accordance with the spectroscopic data. Calculated excitation energies for many Rydberg states of K and Cs indicate that spin-orbit terms in the REP, which are derived for the ground state, are also reliable for the description of highly excited states. The electronic states of the polyatomic molecule CH3I are probed from the molecular region to the dissociation limit. Test calculations demonstrate that the present KRCI is a useful method for the description of potential energy surface of polyatomic molecules containing heavy atoms.

• 한국압력기기공학회 논문집
• /
• 제14권2호
• /
• pp.49-58
• /
• 2018

The regulatory periodic inspection program (PSI) conducted at every overhaul period is the most important process for confirming the safety of nuclear power plants. The PSI for operating nuclear power plants in Korea mainly consist of component level performance check that had been developed based on deterministic approach putting the same degree of importance to all the inspection items. This inspection methodology is likely to be effective for preoperational inspection. However, once the plant is put into service, the PSI must be focused on whether to minimize the risk of accident using defense-in-depth concept and risk insight. The incorporation of defense-in-depth concept and risk insight into the deterministic based safety inspection has not been well studied so far. In this study, two track approaches are proposed to make sure that core damage be avoided: one is to secure success path and the other to block the failure path in a specific event tree of PSA. The investigation shows how to select safety important components and how to set up inspection group to ensure that core damage would not occur for a given initiating event, which results in strengthening defense-in-depth level 3.

• 천문학회보
• /
• 제44권1호
• /
• pp.76.1-76.1
• /
• 2019

CTA 102, one of gamma-ray bright active galactic nuclei (AGN) has been observed with Korean very long baseline interferometry (VLBI) network (KVN) during the period of 2012 December-2018 May as part of interferometric Monitoring Of Gamma-ray Bright AGN (iMOGABA). Multi-frequency VLBI observations enable us to compare the milliarcsecond(mas)-scale iMOGABA images of relativistic jets with those from the Monitoring Of Jets in AGN with Very long baseline array (VLBA) Experiments (MOJAVE) and the VLBA-Boston University(BU)-BLAZAR programs which use VLBA with its angular resolutions of 0.2-1.3 mas. In spite of the relative larger beam sizes of KVN (1-10 mas), we are able to identify jet components of CTA 102 using the KVN multi-frequency VLBI observations with those resolved with VLBA. Considering an instrumental beam blending effect on the jet component identification, we were able to obtain a blending shift of the core position based on a convolution analysis using the VLBA data. When we apply the core position shift to the KVN images of CTA 102, we find that the identified jet components of CTA 102 from the KVN observations are well matched with those from the VLBA observations. Based on the results of the analysis, we may be able to study the jet kinematics and its correlation with gamma-ray flare activity.

• 방사성폐기물학회지
• /
• 제18권4호
• /
• pp.481-496
• /
• 2020

After nuclear power plants are permanently shut down and decommissioned, the remaining irradiated metal components such as stainless steel, carbon steel, and Inconel can be used as neutron absorber. This study investigates the possibility of reusing these metal components as neutron absorber materials, that is burnable poison. The absorption cross section of the irradiated metals did not lose their chemical properties and performance even if they were irradiated over 40-50 years in the NPPs. To examine the absorption capability of the waste metals, the lattice calculations of WH 17×17 fuel assembly were analyzed. From the results, Inconel-718 significantly hold-down fuel assembly excess reactivity compared to stainless steel 304 and carbon steel because Inconel-718 contains a small amount of boron nuclide. From the results, a 20wt% impurity of boron in irradiated Inconel-718 enhances the excess reactivity suppression. The application of irradiated Inconel-718 as a burnable absorber for SMR core was investigated. The irradiated Inconel-718 impurity with 20wt% of boron content can maintain and suppress the whole core reactivity. We emphasize that the irradiated metal components can be used as burnable absorber materials to control the reactivity of commercial reactor power and small modular reactors.