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71.
Electromagnetic shielding properties of soft magnetic metal and ferrite composites for application to suppress noise in a radio frequency range 总被引:1,自引:0,他引:1
Yong Woon Yun Sang Woo Kim Gwang Yoon Kim Yoon Bae Kim Yeo Chun Yun Kyung Sup Lee 《Journal of Electroceramics》2006,17(2-4):467-469
Electromagnetic shielding properties of soft magnetic metal alloy (Fe-Al-Si) flakes and Ni-Zn ferrite composites for effective
suppression of broadband and high frequency noise were investigated. In the soft magnetic composites, the maxima of reflection
loss were shifted to high frequency with increase in content of Ni-Zn ferrite. The composites with content of 50 and 70% ferrite
exhibited broadband absorptive characteristics. The broadband character- istics might be caused by the extended resonance
due to an overlap between imaginary permeability and permittivity of the two composites over the frequency range from 2 to
10 GHz. 相似文献
72.
Hot band annealing is known to be a prerequisite for good magnetic properties irrespective of manufacturing methods in grain‐oriented Fe‐3 wt.% Si electrical steels. In this study, the effects of hot band annealing on magnetic properties were investigated in 3% grain‐oriented electrical steels of low soluble AI contents and one‐stage cold rolling. Microstructure and precipitate distribution were compared with hot band annealing conditions. Secondary recrystallization behaviour with hot band annealing condition was also discussed. 相似文献
73.
Kyung Ho Kim Seong Jin Park Jin Jang 《Journal of the Society for Information Display》2003,11(4):611-615
Abstract— We studied the silicide‐mediated crystallization of a‐Si for low‐temperature polycrystalline‐silicon (LTPS) on glass. By controling the heating method and Ni density on the a‐Si, the grain size could be increased to 40 μm. Radial grain growth from a NiSi2 crystalline nucleus gives rise to a large‐grain poly‐Si without amorphous phase inside. A field‐effect mobility of over 200 cm2/V‐sec was achieved by using LTPS. 相似文献
74.
Min-Ho Kyung Author Vitae Author Vitae 《Computer aided design》2003,35(10):901-911
This paper presents a nonlinear kinematic tolerance analysis algorithm for planar mechanical systems comprised of higher kinematic pairs. The part profiles consist of line and circle segments. Each part translates along a planar axis or rotates around an orthogonal axis. The part shapes and motion axes are parameterized by a vector of tolerance parameters with range limits. A system is analyzed in two steps. The first step constructs generalized configuration spaces, called contact zones, that bound the worst-case kinematic variation of the pairs over the tolerance parameter range. The zones specify the variation of the pairs at every contact configuration and reveal failure modes, such as jamming, due to changes in kinematic function. The second step bounds the worst-case system variation at selected configurations by composing the zones. Case studies show that the algorithm is effective, fast, and more accurate than a prior algorithm that constructs and composes linear approximations of contact zones. 相似文献
75.
Young-II Kim Chong-Min Kyung 《Design & Test of Computers, IEEE》2004,21(6):484-493
This hybrid dynamic simulation scheme implements part of the simulator in software running on a processor and maps the rest onto a programmable hardware accelerator. An algorithm for hardware synthesis of behavioral testbenches enables better partitions, resulting in lower communication costs between the two components. TPartition improves the performance of hardware accelerated simulation without a designer's remodeling effort and without losing compatibility with the original testbench. 相似文献
76.
Seok Jin Lim Suk Jae Jeong Kyung Sup Kim Myon Woong Park 《The International Journal of Advanced Manufacturing Technology》2006,28(5-6):618-625
Today’s business environment is experiencing as a period of expansion and the globalization. Therefore, a distribution plan
with low cost and high customer satisfaction in supply chain management (SCM) has been widely investigated. The purpose of
this study is to establish optimal distribution planning in the supply chain. In this paper, a hybrid approach involving a
genetic algorithm (GA) and simulation is presented to solve this problem. The GA is employed in order to quickly generate
feasible distribution sequences. Considering uncertain factors such as queuing, breakdowns and repairing time in the supply
chain, the simulation is used to minimize completion time for the distribution plan. The computational results for an example
of a simple supply chain are given and discussed to validate the proposed approach. We obtained a more realistic distribution
plan with optimal completion time by performing the iterative hybrid GA simulation procedure which reflects the stochastic
nature of supply chains. 相似文献
77.
This paper reports a technique for measuring the velocity and dissolved oxygen concentration (DOC) fields simultaneously in a micro-scale water flow using oxygen-sensitive particles (OSP) and a conventional microparticle image velocimetry method. The OSP were fabricated using a dispersion polymerization method by synthesizing platinum (II) octaethyporphyrin (PtOEP) with polystyrene, and used as tracer particles and oxygen sensors. An ultraviolet light-emitting diode with a wavelength of 385 nm was used as the excitation light source, and phosphorescence images of OSP were captured on a CMOS high-speed camera. The interrogation window concept was used to measure the DOC in water from the dispersed phosphorescence intensity distribution of OSP. The Stern–Volmer equations in the interrogation windows were obtained from in situ calibration. Water containing OSP with DOC values of 0 and 100 % were injected into a Y-shaped microchannel using a double loading syringe pump. The velocity and DOC field over the entire channel area were quantified. 相似文献
78.
Gaseous Nanocarving‐Mediated Carbon Framework with Spontaneous Metal Assembly for Structure‐Tunable Metal/Carbon Nanofibers
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Dae‐Hyun Nam Sungwoo Lee Young‐Joo Lee Jun‐Hyun Jo Euijoon Yoon Kyung‐Woo Yi Gun‐Do Lee Young‐Chang Joo 《Advanced materials (Deerfield Beach, Fla.)》2017,29(38)
Vapor phase carbon (C)‐reduction‐based syntheses of C nanotubes and graphene, which are highly functional solid C nanomaterials, have received extensive attention in the field of materials science. This study suggests a revolutionary method for precisely controlling the C structures by oxidizing solid C nanomaterials into gaseous products in the opposite manner of the conventional approach. This gaseous nanocarving enables the modulation of inherent metal assembly in metal/C hybrid nanomaterials because of the promoted C oxidation at the metal/C interface, which produces inner pores inside C nanomaterials. This phenomenon is revealed by investigating the aspects of structure formation with selective C oxidation in the metal/C nanofibers, and density functional theory calculation. Interestingly, the tendency of C oxidation and calculated oxygen binding energy at the metal surface plane is coincident with the order Co > Ni > Cu > Pt. The customizable control of the structural factors of metal/C nanomaterials through thermodynamic‐calculation‐derived processing parameters is reported for the first time in this work. This approach can open a new class of gas–solid reaction‐based synthetic routes that dramatically broaden the structure‐design range of metal/C hybrid nanomaterials. It represents an advancement toward overcoming the limitations of intrinsic activities in various applications. 相似文献
79.
Hur JH Kim KM Chang M Lee SR Lee D Lee CB Lee MJ Kim YB Kim CJ Chung UI 《Nanotechnology》2012,23(22):225702
We report a physical model for multilevel switching in oxide-based bipolar resistive memory (ReRAM). To confirm the validity of the model, we conduct experiments with tantalum-oxide-based ReRAM of which multi-resistance levels are obtained by reset voltage modifications. It is also noticeable that, in addition to multilevel switching capability, the ReRAM exhibits extremely different switching timescales, i.e. of the order of 10(-7)?s to 10(0)?s, with regard to reset voltages of only a few volts difference which can be well explained by our model. It is demonstrated that with this simple model, multilevel switching behavior in oxide bipolar ReRAM can be described not only qualitatively but also quantitatively. 相似文献
80.
Hye Kyung Choi Geun Cheol Song Hwe-Su Yi Choong-Min Ryu 《Journal of chemical ecology》2014,40(8):882-892
Plants are defended from attack by emission of volatile organic compounds (VOCs) that can act directly against pathogens and herbivores or indirectly by recruiting natural enemies of herbivores. However, microbial VOC have been less investigated as potential triggers of plant systemic defense responses against pathogens in the field. Bacillus amyloliquefaciens strain IN937a, a plant growth-promoting rhizobacterium that colonizes plant tissues, stimulates induced systemic resistance (ISR) via its emission of VOCs. We investigated the ISR capacity of VOCs and derivatives collected from strain IN937a against bacterial spot disease caused by Xanthomonas axonopodis pv. vesicatoria in pepper. Of 15 bacterial VOCs and their derivatives, 3-pentanol, which is a C8 amyl alcohol reported to be a component of sex pheromones in insects, was selected for further investigation. Pathogens were infiltrated into pepper leaves 10, 20, 30, and 40 days after treatment and transplantation to the field. Disease severity was assessed 7 days after transplantation. Treatment with 3-pentanol significantly reduced disease severity caused by X. axonopodis and naturally occurring Cucumber mosaic virus in field trials over 2 years. We used quantitative real-time polymerase chain analysis to examine Pathogenesis-Related genes associated with salicylic acid (SA), jasmonic acid (JA), and ethylene defense signaling. The expression of Capsicum annuum Pathogenesis-Related protein 1 (CaPR1), CaPR2, and Ca protease inhibitor2 (CaPIN2) increased in field-grown pepper plants treated with 3-pentanol. Taken together, our results show that 3-pentanol triggers induced resistance by priming SA and JA signaling in pepper under field conditions. 相似文献