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101.
The relationship between video gameplay, video game genre preference, personality, and GPA was investigated in an online correlational study with university students. In addition to administering self-report measures of GPA and personality, we asked three different questions regarding styles of video gameplay. The first asked the average time spent playing video games per week (habitual players), the second asked the total time spent playing favorite video games (selective players), and the third asked the number of different video games played in a year (diverse players). Students who were medium in selective player style (spent 11-50 h) had significantly higher GPAs than students low on selective player style (spent 0-10 h). Students high on habitual playing style (7 or more hours a week) showed significantly lower levels of Conscientiousness compared to students low on habitual playing style (0-1 h a week). Students who were high on the diverse style (i.e., 7 or more games played a year) showed significantly higher Openness scores than students low on the diverse style (0-3 games a year). Finally, several notable relations were found between video game genre preference, GPA, and personality. Results are discussed in terms of the positive implications of video gameplay on academic performance. 相似文献
102.
We have investigated the structure-property relationships and the effects of a viscosity ratio on the rheological properties of nanocomposite-like polymer blends using oscillatory and steady shear rheometry and optical microscopy. These immiscible blends are consisted of ultrahigh viscous polybutadiene (PB1), high viscous polybutadien (PB2), and low viscous polydimethylsiloxane (PDMS). The PB1/PDMS blends with an ultrahigh viscosity ratio (λ=162,000) exhibit non-Newtonian fluids behavior for Ω≥0.1 while the PDMS/PB2 blends (λ=37) exhibit pseudo-Newtonian fluids behavior for Ω>0.6, where Ω is the weight fraction of PB1 or PB2 in the blends. The viscoelastic properties of the PB1/PDMS blends increase systematically with an increasing the weight fraction of PB1, and then exhibit plateau values above a certain maximum weight fraction (Ωm) of PB1. In addition the viscoelastic properties of the PB1/PDMS blends are not affected by the change of blend morphology or phase inversion, where Ωm is larger than the phase inversion weight fraction (Ωp). In contrast the viscoelastic properties of the PB2/PDMS blends follow a positive-deviation mixing rule and are significantly affected by phase inversion. 相似文献
103.
Novel universal method for measurement of the condensation coefficient α is developed. Using this method, noticeable difference between measured (α≈0.8) and expected (α≈1) values of the condensation coefficient for sputtered Cr atoms was revealed for the first time. The effect is assumed to be a result of considerable elevation of the surface temperature during atomic condensation induced by the energy delivered to the condensation surface by sputtered atoms and from the plasma. 相似文献
104.
Youngha Kim Sungkwan Kim Young-Ah Jeon Yunseok Kim Hanjong Paik Yangsoo Kim Sang-Chul Han Young-Hee Han Nyeon-Ho Jeong Tae-Hyun Sung Jong-In Hong Kwangsoo No 《Journal of Electroceramics》2006,17(2-4):1063-1067
YBa2Cu3Ox (Y123) superconducting films were fabricated on Cu substrates using a simple screen-printing method, from Cu-free powders
(Y2O3 and BaCO3). In the process, CuO, which causes superconducting properties of Y123 films to deteriorate, was formed on the film surface.
By varying the atomic ratio of Y to Ba (Y:Ba = 1:1∼1:4), the ratio needed to prevent CuO formation was found for the film
surface that had been heat-treated at 980∘C for 17 s. The film, with the ratio of Y to Ba (Y:Ba = 1:1), is reheat-treated at 930∘C for 9 min 30 s to form a superconducting Y123 phase. It was possible to prevent CuO formation by controlling the ratio of
Cu-free powders in the mixture and to fabricate YBCO superconductors on Cu substrates using a two-step heat-treatment. 相似文献
105.
Kun-Mo Chu Jung-Hwan Choi Jung-Sub Lee Han Seo Cho Seong-Ook Park Hyo-Hoon Park Duk Young Jeon 《Advanced Packaging, IEEE Transactions on》2006,29(3):409-414
This paper describes low-temperature flip-chip bonding for both optical interconnect and microwave applications. Vertical-cavity surface-emitting laser (VCSEL) arrays were flip-chip bonded onto a fused silica substrate to investigate the optoelectronic characteristics. To achieve low-temperature flip-chip bonding, indium solder bumps were used, which had a low melting temperature of 156.7/spl deg/C. The current-voltage (I-V) and light-current (L-I) characteristics of the flip-chip bonded VCSEL arrays were improved by Ag coating on the indium bump. The I-V and L-I curves indicate that optical and electrical performances of Ag-coated indium bumps are superior to those of uncoated indium solder bumps. The microwave characteristics of the solder bumps were investigated by using a flip-chip-bonded coplanar waveguide (CPW) structure and by measuring the scattering parameter with an on-wafer probe station for the frequency range up to 40 GHz. The indium solder bumps, either with or without the Ag coating, provided good microwave characteristics and retained the original characteristic of the CPW signal lines without degradation of the insertion and return losses by the solder bumps. 相似文献
106.
Yuqi Wang K.H. Low H.L.J. Pang K.H. Hoon F.X. Che Y.S. Yong 《Microelectronics Reliability》2006,46(2-4):558-573
Multi-layered printed circuit boards (PCBs) contain a multi-layered structure that is suitable for high-speed and high-frequency applications. Hence, they are used extensively in electronic packaging assemblies for high-density applications. However, numerous composite parts and complex material properties of multi-layer PCBs complicate the reliability simulation of PCB model. This paper deals with a finite element analysis intended to describe numerically the behavior of multi-layered multi-materials PCB model (combination of metallic and composite plies) in the drop-impact performance. Through the comparison of physical drop test results, the fully multi-layered model illustrates higher accuracy if compared with that of the traditional simplified isotropic model and orthotropic model. The effects of material properties for the multi-layer PCB under drop-impact shock have also been investigated. 相似文献
107.
Sung Chan Kim An D. Byeong Ok Lim Tae Jong Baek Dong Hoon Shin Jin Koo Rhee 《Electron Device Letters, IEEE》2006,27(1):28-30
We reported 94-GHz, low conversion loss, and high isolation single balanced active gate mixer based on 70-nm gate length InGaAs/InAlAs metamorphic high-electron mobility transistors (MHEMTs). This mixer showed that the conversion loss and isolation characteristics were 2.5/spl sim/3.5 dB and under -29 dB in the range of 92.95/spl sim/94.5 GHz, respectively. The low conversion loss of the mixer is mainly attributed to the high-performance of the MHEMTs exhibiting a maximum drain current density of 607 mA/mm, an extrinsic transconductance of 1015 mS/mm, a current gain cutoff frequency (f/sub t/) of 330 GHz, and a maximum oscillation frequency (f/sub max/) of 425 GHz. High isolation characteristics are due to hybrid ring coupler which adopted dielectric-supported air-gapped microstrip line structure using surface micromachined technology. To our knowledge, these results are the best performance demonstrated from 94 GHz single balanced mixer utilizing GaAs-based HEMTs in terms of conversion loss as well as isolation characteristics. 相似文献
108.
109.
在60%硫酸乙酯催化下TEOS水解,通过控制水解条件,得到担载体纳米SiO2。采用吸附法在其表面负载银,制备无机抗菌材料。用抑菌圈直径和杀菌率表征粉末抗菌性能,研究了吸附时间、硝酸银浓度及吸附温度与负载量的关系,并考查了焙烧温度等因素对抗菌性能的影响。研究发现,以离子形式存在的贵金属银的抗菌性能强,焙烧处理温度决定其离子溶出性与可重复使用次数。 相似文献
110.