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81.
Although the stringent requirements of some critical applications may require independent certification, the authors see software developer self-certification as a viable alternative in many other cases. They accept that using software certification laboratories (SCLs) may work well for certain software distribution models, but they cannot be applied to all types of software development. The approach has several drawbacks. For example, an SCL may work well for larger software houses that ship mass-marketed software applications to the public, but it is less satisfactory for smaller developers who make reusable components or safety-critical software or for developers who belong to the freeware community  相似文献   
82.
The negative impact of online gaming on adolescents has received much attention. The question of how to reduce their pathological use of online gaming is a critical issue. Based on the concept of external justification in dissonance theory, this experimental study aimed to examine whether severity of threat and justification of effort would impact adolescent players’ attitude change toward online gaming and their subjective estimations of online gaming addiction. The results echoed predictions from classic studies in dissonance theory. When participants engaged in attitude–discrepant behavior, i.e., persuading other adolescents that an apparently interesting online game is not fun at all, their attitudes toward online gaming shifted more dramatically to the negative side in the context of a low level of threat rather than a high level of threat. Additionally, the magnitude of attitude change was more prominent when participants exerted more rather than less effort to engage in attitude–discrepant behavior. Moreover, a similar pattern of participants’ evaluations of the likelihood of online gaming addiction was also observed. The findings show that dissonance theory has the potential to be useful for inducing adolescent players to disengage in online gaming.  相似文献   
83.
84.
The derivation, verification, and implication of the nonlinear dynamic and frequency response of electrostatic actuator due to the double frequency effect (DFE) were reported in this study. In particular, an extra mode called half mode was observed and measured in various studies. However, a complete in-depth discussion of the effect was not reported in the past. In the present study, a second-order dynamical equation was adapted firstly to model the dynamic and frequency response of electrostatic actuator where typical harmonic input signal with a dc bias was used. Secondly, by solving the equation, complex waveform in dynamic response and an extra half mode in frequency response due to the double frequency effect can be observed and discussed. To verify the simulated result, an electrostatic driving device was fabricated using PolyMUMPS© process. Note that in frequency response, when dc bias is equal to the amplitude of ac signal, simulated and experimental results indicated that the amplitude of half mode was one-fourth of first mode.  相似文献   
85.
A general relation, considering the interface conditions, between a sampled point and its nearby points is derived. Making use of the derived relation and the generalized Douglas scheme, the three point formulas in the finite-difference modeling of step-index optical devices are extended to fourth order accuracy irrespective of the existence of the step-index interfaces. With numerical analysis and numerical assessment, several frequently used formulas are investigated  相似文献   
86.
87.
Glasses in the PbO-B2O3-Al2O3-BaO-CaO-SiO2 system were employed as the dopant to ZnO varistors. The thermal stability of the varistor is enhanced with glass additives. The temperature coefficient of threshold field for the sample doped with 1 w/o glass (65 w/o PbO - 23 w/o B2O3 - 12 w/o SiO2) is 1 × 10-4/K as compared to 3.3 × 10-3/K for that of the undoped sample. The change in the temperature dependence of the field-current density characteristics is more related to the barrier height change than the refractory behavior of the glass employed. Heat treatment is very effective in recovering the degraded samples by providing the activation energy for the diffusion of Zn interstitials. The experimental results can be explained with a Schottky barrier model.  相似文献   
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89.
Catalytic incineration is one of the cost-effective technologies to solve troublesome volatile organic compounds. However, some sulfur containing volatile organic compounds, such as ethyl mercaptan, may deactivate the Pt catalyst that is commonly used in the catalytic incineration process. This paper provides information on the poisoning effect of ethyl mercaptan. The catalytic incineration of ethyl mercaptan, typically emitted from the petrochemical industry, over a Pt/Al2O3 fixed-bed catalytic reactor was studied. The effects of operating parameters including inlet temperature, space velocity, C2H5SH concentration, O2 concentration, and catalyst size were characterized. Catalytic incineration on a mixture of C2H5SH with CH3SH was also tested. The results show that the conversions of C2H5SH increase as the inlet temperature increases and the space velocity decreases. For the temperature from 200–260°C, the higher the C2H5SH concentration is, the lower its conversion. The O2 concentration has a positive effect on the conversion of C2H5SH. C2H5SH has a poisoning effect on the Pt/Al2O3 catalyst, especially at lower temperature. The existence of CH3SH has no effects on the conversion of C2H5SH.  相似文献   
90.
Computational Economics - With the progress of financial technology (FinTech), real-time information from FinTech is huge and complicated. For various fields of research, identifying intrinsic...  相似文献   
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