Comparative Investigation of the High Pressure Autoignition of the Butanol Isomers

Investigation of the autoignition delay of the butanol isomers has been performed at elevated pressures of 15 bar and 30 bar and low to intermediate temperatures of 680-860 K. The reactivity of the stoichiometric isomers of butanol, in terms of inverse ignition delay, was ranked as n-butanol > sec-butanol ~ iso-butanol > tert-butanol at a compressed pressure of 15 bar but changed to n-butanol > tert-butanol > sec-butanol > iso-butanol at 30 bar. For the temperature and pressure conditions in this study, no NTC or two-stage ignition behavior were observed. However, for both of the compressed pressures studied in this work, tert-butanol exhibited unique pre-ignition heat release characteristics. As such, tert-butanol was further studied at two additional equivalence ratios ($\phi$ = 0.5 and 2.0) to help determine the cause of the heat release.Comment: 4 pages, 4 figures, presented at the 2011 Meeting of the Eastern States Sections of the Combustion Institut

Accelerating moderately stiff chemical kinetics in reactive-flow simulations using GPUs

The chemical kinetics ODEs arising from operator-split reactive-flow simulations were solved on GPUs using explicit integration algorithms. Nonstiff chemical kinetics of a hydrogen oxidation mechanism (9 species and 38 irreversible reactions) were computed using the explicit fifth-order Runge-Kutta-Cash-Karp method, and the GPU-accelerated version performed faster than single- and six-core CPU versions by factors of 126 and 25, respectively, for 524,288 ODEs. Moderately stiff kinetics, represented with mechanisms for hydrogen/carbon-monoxide (13 species and 54 irreversible reactions) and methane (53 species and 634 irreversible reactions) oxidation, were computed using the stabilized explicit second-order Runge-Kutta-Chebyshev (RKC) algorithm. The GPU-based RKC implementation demonstrated an increase in performance of nearly 59 and 10 times, for problem sizes consisting of 262,144 ODEs and larger, than the single- and six-core CPU-based RKC algorithms using the hydrogen/carbon-monoxide mechanism. With the methane mechanism, RKC-GPU performed more than 65 and 11 times faster, for problem sizes consisting of 131,072 ODEs and larger, than the single- and six-core RKC-CPU versions, and up to 57 times faster than the six-core CPU-based implicit VODE algorithm on 65,536 ODEs. In the presence of more severe stiffness, such as ethylene oxidation (111 species and 1566 irreversible reactions), RKC-GPU performed more than 17 times faster than RKC-CPU on six cores for 32,768 ODEs and larger, and at best 4.5 times faster than VODE on six CPU cores for 65,536 ODEs. With a larger time step size, RKC-GPU performed at best 2.5 times slower than six-core VODE for 8192 ODEs and larger. Therefore, the need for developing new strategies for integrating stiff chemistry on GPUs was discussed.Comment: 27 pages, LaTeX; corrected typos in Appendix equations A.10 and A.1

UConnRCMPy: Python-based data analysis for rapid compression machines

The ignition delay of a fuel/air mixture is an important quantity in designing combustion devices, and these data are also used to validate chemical kinetic models for combustion. One of the typical experimental devices used to measure the ignition delay is called a Rapid Compression Machine (RCM). This paper presents UConnRCMPy, an open-source Python package to process experimental data from the RCM at the University of Connecticut. Given an experimental measurement, UConnRCMPy computes the thermodynamic conditions in the reaction chamber of the RCM during an experiment along with the ignition delay. UConnRCMPy implements an extensible framework, so that alternative experimental data formats can be incorporated easily. In this way, UConnRCMPy improves the consistency of RCM data processing and enables the community to reproduce data analysis procedures.Comment: 8 pages, 3 figures, presented at the 10th US National Combustion Meetin

Ultrabright Backward-wave Biphoton Source

We calculate the properties of a biphoton source based on resonant backward-wave spontaneous parametric down-conversion. We show that the biphotons are generated in a single longitudinal mode having a subnatural linewidth and a Glauber correlation time exceeding 65 ns.Comment: 4 pages, 3 figure

Unfair Competition Issues of Big Data in China

The sound development of the market in the data-driven economy depends on the free and fair competition of big data in the industries. Since 2015, more and more unfair competition cases concerning big data have occurred in China, such as masking advertisement, click fraud, malicious incompatibility, and gathering user’s personal data from competitors by unfair means, which can be categorized to unfair competition about illegal collection/use of competitors’ big data and about network traffic. Whether China’s current legal system of anti-unfair competition can resolve the above-mentioned disputes is concerned in this article. As the Paris Convention only regulates the basic principles of “fairness” and “honest practice” for anti-unfair competition, member states have room to develop their own legal systems according to their special economic, social and cultural conditions. In order to usher in the era of digital economy and big data and to regulate more and more unfair competition events, China amended the Anti-Unfair Competitive Law in 2017 in which a new provision for regulating the operation of e-commerce was added. This article finds that the 2017 Amendment, which is far more specific and clearer than the Paris Convention, has significantly improved China’s ability to deal with unfair competition behaviors regarding big data. However, since the patterns of unfair competition in big data are changing and “innovating” quickly and constantly, law amendments will hardly or even never catch up with the changes, so judgement of unfair competition is inherently difficult. The court cannot determine that a company constitutes unfair competition simply because its business operations have substantially reduced the performance or operating effectiveness of its competitors. When judging whether an enterprise’s competitive behavior constitutes unfair competition, no matter the court is applying one of the specific provisions or the general provision, it is essential to consider whether the enterprise has malicious and dishonest practices

When Open Source Software Encounters Patents: Blockchain as an Example to Explore the Dilemma and Solutions, 18 J. Marshall Rev. Intell. Prop. L. 55 (2018)

The original blockchain developers set the core programs, development interfaces, and application software of the blockchain as open source software, which are open to all developers for free. They have never thought of collecting royalties by claiming copyright, nor did they apply for patents. Since then, however, many follow-up blockchain developers applied the core programs to further developments and filed a large numbers of patent applications, causing the original blockchain developers to be very concerned about whether these patents will otherwise slow down or even endanger the innovation of blockchain technology. Consequently, finding legal solutions for the conflicts between open source software and patent rights hence becomes an important research topic in the field of intellectual property rights. This article discusses three possible solutions to the conflict: the licensing schemes of industrial standard, the licensing schemes of open source software, and the open patent campaigns, pointing out that at the moment all three have an opportunity to solve the problem, while also acknowledging that there are still many issues to be solved. In terms of the licensing schemes of industrial standard, this article considers that the industrial standard of blockchain should require the patentees involved in standard setting to disclose their patents, and should require the owners of the standard essential patents to not refuse the patent licensing. To determine what licensing scheme the blockchain standard should adopt, this article conducts a legal and economic analysis by studying its technical attributes, the process of patent thicketing, and the development of the industry, suggesting that the “Patent Policy” of the blockchain standard should at least follow the fair, reasonable, and non-discriminatory (FRAND) license adopted by many industrial standards such as the telecommunication industry. As a result, users of blockchain could access the patented technologies more conveniently. In terms of the licensing schemes of open source software, this article finds that the MIT license for the Bitcoin Blockchain and the GNU GPL license for the Ethereum Blockchain cannot solve the problem of follow-up developers not drafting a software code, but instead applying for patents for the resulting follow-up developments. This article compares the similarities and differences of other open source software programs, studies the original philosophical spirit and technological and industrial development of blockchains, and suggests a suitable licensing scheme of open source software for the blockchain technology. Lastly, this article finds open patents to be a possible solution to the patent problems faced by the blockchain technology, but concludes that this solution is more challenging with blockchain than in other industries because open patent campaigns rely on the spontaneous action of the patentee. The blockchain industry, especially the original developers of the core blockchain technology, should provide incentives for the right holders of subsequent patent applications to willingly and spontaneously open their patents