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1.
Since the inception of blockchain-related technologies over a decade ago, investors’ uptake of the technologies has grown rapidly. But even with the advancement in standing from conceptual beginnings to real-world experimentation, mainstream adoption of the technologies in either organizational or individual contexts has yet to eventuate. To resolve this paradox, we examine progression of the technologies’ diffusion instead, and in the process, seek to uncover the underlying dynamics of sentiments at play. Diffusion involves multiple actions by different parties, with social discourses via diverse media playing an essential role. In demonstrating the interplay of support to resistance via media framing and the diffusion of innovation theory, findings from our paper contribute to the technology adoption literature. Understanding resistant behavior toward a new technology area could help resolve potential issues that may arise. This would hopefully lead to better technological implementation outcomes in future. 相似文献
2.
We examine the quantum effect of cooling down the environment temperature of mesoscopic LC circuit, and find that the ground state of the circuit is no longer in the thermo vacuum state, but in a negative binomial state. We calculate energy of the circuit in this new state, which increases with the cooling of the environment. 相似文献
3.
Tahir Mahmood 《Quality and Reliability Engineering International》2020,36(5):1570-1591
Emerge in technology brought well-organized manufacturing systems to produce high-quality items. Therefore, monitoring and control of products have become a challenging task for quality inspectors. From these highly efficient processes, produced items are mostly zero-defect and modeled based on zero-inflated distributions. The zero-inflated Poisson (ZIP) and zero-inflated Negative Binomial (ZINB) distributions are the most common distributions, used to model the high-yield and rare health-related processes. Therefore, data-based control charts under ZIP and ZINB distributions (i.e., Y-ZIP and Y-ZINB) are proposed for the monitoring of high-quality processes. Usually, with the defect counts, few covariates are also measured in the process, and the generalized linear model based on the ZIP and ZINB distributions are used to estimate their parameters. In this study, we have designed monitoring structures (i.e., PR-ZIP and PR-ZINB) based on the ZIP and ZINB regression models which will provide the monitoring of defect counts by accounting the single covariate. Further, proposed model-based charts are compared with the existing data-based charts. The simulation study is designed to access the performance of monitoring methods in terms of run length properties and a case study on the number of flight delays between Atlanta and Orlando during 2012–2014 is also provided to highlight the importance of the stated research. 相似文献
4.
Yo-Sheng Lin Kai-Siang Lan Ming-Yuan Chuang Yu-Ching Lin 《International Journal of Electronics》2018,105(6):1063-1077
This paper reports a 94 GHz CMOS voltage-controlled oscillator (VCO) using both the negative capacitance (NC) technique and series-peaking output power and phase noise (PN) enhancement technique. NC is achieved by adding two variable LC networks to the source nodes of the active circuit of the VCO. NMOSFET varicaps are adopted as the required capacitors of the LC networks. In comparison with the conventional one, the proposed active circuit substantially decreases the input capacitance (Cin) to zero or even a negative value. This leads to operation (or oscillation) frequency (OF) increase and tuning range (TR) enhancement of the VCO. The VCO dissipates 8.3 mW at 1 V supply. The measured TR of the VCO is 91~96 GHz, close to the simulated (92.1~96.7 GHz) and the calculated one (92.2~98.2 GHz). In addition, at 1 MHz offset from 95.16 GHz, the VCO attains an excellent PN of – 98.3 dBc/Hz. This leads to a figure-of-merit (FOM) of ?188.5 dBc/Hz, a remarkable result for a V- or W-band CMOS VCO. The chip size of the VCO is 0.75 × 0.42 mm2, i.e. 0.315 mm2. 相似文献
5.
Milinda Pattanayak Md Nadim F Hoque Zhaoyang Fan Ayrton A. Bernussi 《Science and Technology of Advanced Materials》2018,19(1):693-701
We report large amplitude modulation waveforms as large as ~ 10 V using vanadium dioxide micro-channel devices operating under current-controlled conditions. The self-sustained electrical oscillations were generated by controlling the applied current in the negative differential resistance region of the investigated devices. An appropriate value of internal capacitance was achieved as parasitic capacitance in the device structure to stabilize the electrical oscillations. This eliminates the need of an external pulsed source or any external passive component connected to the micro-channel devices. Amplitude and frequency of the oscillation were tuned by illuminating the device micro-channel with an external laser. An equivalent circuit model was developed to simulate the waveforms. A good agreement between experiment and simulation was verified. 相似文献
6.
针对尾撑式风洞模型强方向性振动问题,基于异位配置加速度负反馈控制器对风洞模型振动主动控制方法进行研究。首先,通过模态分析得到系统低阶模态振动的强方向性并基于系统特性设计了具有结构耦合性的内嵌压电陶瓷作动器的风洞模型振动主动控制系统。然后,基于异位配置NAF控制器分别设计了针对第二阶模态和前两阶模态的单模态NAF控制算法和双模态NAF控制算法。最后,进行了实验验证,结果表明:双模态NAF控制算法控制效果较好,前两阶模态阻尼比分别提高近13倍和近40倍,镇定时间分别缩短近11s和近26s。 相似文献
7.
Magalí Rey-Campos Beatriz Novoa Alberto Pallavicini Marco Gerdol Antonio Figueras 《International journal of molecular sciences》2021,22(6)
Mytimycins are cysteine-rich antimicrobial peptides that show antifungal properties. These peptides are part of the immune network that constitutes the defense system of the Mediterranean mussel (Mytilus galloprovincialis). The immune system of mussels has been increasingly studied in the last decade due to its great efficiency, since these molluscs, particularly resistant to adverse conditions and pathogens, are present all over the world, being considered as an invasive species. The recent sequencing of the mussel genome has greatly simplified the genetic study of some of its immune genes. In the present work, we describe a total of 106 different mytimycin variants in 16 individual mussel genomes. The 13 highly supported mytimycin clusters (A–M) identified with phylogenetic inference were found to be subject to the presence/absence variation, a widespread phenomenon in mussels. We also identified a block of conserved residues evolving under purifying selection, which may indicate the “functional core” of the mature peptide, and a conserved set of 10 invariable plus 6 accessory cysteines which constitute a plastic disulfide array. Finally, we extended the taxonomic range of distribution of mytimycins among Mytilida, identifying novel sequences in M. coruscus, M. californianus, P. viridis, L. fortunei, M. philippinarum, M. modiolus, and P. purpuratus. 相似文献
8.
AbstractA mechanical model of steel-concrete composite beams considering horizontal slip and vertical pull-out effects under negative bending moment was established based on the theory of elastic deformation. By using the principle of force equilibrium and deformation compatibility condition, the differential equation was derived and deduced using computational calculation program, in which the formula of the pull-out force in shear connectors under negative bending moment was obtained. The experiment was conducted in order to verify the reliability of theoretical results. The results show: under the same load condition, the pull-out force of a single stud increases with the increase of the stud spacing. All the theoretical results were verified by comparing with experiment results to illustrate the accuracy and reliability of the calculation method. It provides a theoretical reference for the study of the interface interaction considering horizontal slip and vertical pull-out effect in the negative bending moment region of continuous composite beams. 相似文献
9.
隔震技术能有效减小核电厂上部结构的加速度响应,但强地震作用下隔震层位移过大会导致管道断裂。本文基于曲面运动原理及预压弹簧伸缩特性提出了一种负刚度阻尼系统,通过球铰在拱球面曲线运动实现负刚度特性,并在弹簧压缩方向提供黏滞阻尼性能。提出了负刚度系统的理论恢复力模型并进行了力学特性分析,设计了负刚度装置并完成了静力试验,结果显示理论恢复力模型与试验结果的一致性较理想。将核电厂负刚度阻尼隔震结构与核电厂隔震结构进行了地震响应对比分析,比较了不同地震波输入下的地震响应。结果表明负刚度阻尼系统可有效同时减小核电厂上部加速度响应和隔震层位移响应。 相似文献
10.
In May 2018,the primetime news casted a shocking report saying that radon concentration on a certain model of bed mattress found to be as high as 2 200 Bq/m3.After a humble,the Nuclear Safety and Security Commission(NSSC) of Korea confirmed that significant amount of thoron gas is emanated from several mattress models marketed by a company claiming beneficial health effects of negative ions.Laboratory analysis showed that some internal fabric sheets of those mattresses contain high concentration of Th-232.It was revealed that the manufacture treated the material with so-called ‘negative ion powder’ procured from the market and NSSC found that its radioactive content is the monazite powder.Although measurements with reliable instruments resulted in somewhat lower values,the tentative but conservative estimates of doses to the users are still remarkable,ranging from a few to 14 mSv a year.Most of the affected models have been marketed from 2010 but earlier models,with lower thorium content,were supplied from 2006.As many as 88,000 mattresses have been produced.The manufacturer with help of the government,recalled all the affected models and separated the radioactive internals.A large amount of waste is waiting for the government decision on disposal method.Similar problems were identified in other consumer products including latex mattresses and pillows imported,hot pads,and several models of sanitary or health-aid goods.These episodes called for revisiting NORM control strategy in Korea. 相似文献