Well-Rounded ideal lattices of cyclic cubic and quartic fields

In this paper, we find criteria for when cyclic cubic and cyclic quartic fields have well-rounded ideal lattices. We show that every cyclic cubic field has at least one well-rounded ideal. We also prove that there exist families of cyclic quartic fields which have well-rounded ideals and explicitly construct their minimal bases. In addition, for a given prime number $p$, if a cyclic quartic field has a unique prime ideal above $p$, then we provide the necessary and sufficient conditions for that ideal to be well-rounded. Moreover, in cyclic quartic fields, we provide the prime decomposition of all odd prime numbers and construct an explicit integral basis for every prime ideal.Comment: 26 page

Well-Rounded Twists of Ideal Lattices from Imaginary Quadratic Fields

In this paper, we investigate the properties of well-rounded twists of a given ideal lattice of an imaginary quadratic field $K$. We show that every ideal lattice $I$ of $K$ has at least one well-rounded twist lattice. Moreover, we provide an explicit algorithm to compute all well-rounded twists of $I$.Comment: 24 page

A Scalable Wi-Fi Based Localization Algorithm

This paper proposes an applicable and scalable approach which allows deploying the fingerprint Wi-Fi localization algorithm for different mobile devices. The original fingerprint localization algorithm performs accurately when the mobile device used in the deployment phase is the same as the mobile device used in the training phase. However, when a different mobile device is used in the deployment phase, a time-consuming re-training step (in the order of hours or days) is required to achieve the equivalent degree of accuracy. Our proposed approach replaces this re-training step by a short period of calibration (in the order of a few minutes), which can be done transparently to the user. To validate our approach, we did an analysis on collected data from a large scale experiment (14 laptops and 2 smartphones with 224-hour of collected data) and evaluated the performance on the real devices

ZSM-5/SBA-15 versus Al-SBA-15 as supports for the hydrocracking/hydroisomerization of alkanes

[EN] Al-SBA-15 and ZSM-5/SBA-15 (ZSC) composite were synthesized following hydrothermal procedures in the presence of triblock copolymer Poly(ethylene glycol)- poly(propylene glycol)-poly(ethylene glycol) (Pluronic P123) and a mixture of tetrapropylammonium bromide (TPABr)/Pluronic P123 templates, respectively. Pt (0.5 wt.%)/Al-SBA-15 and ZSC bifunctional catalysts were then prepared by a wet impregnation methodology and investigated in the hydrocracking/hydroisomerization of n-decane. Pt/ZSC, containing a trimodal porous texture and high Bronsted acidity, exhibited hydrocracking activity while Pt/Al-SBA-15, showing merely Lewis acidity, was active for hydroisomerization. At 300 degrees C the conversion of n-decane on Pt/ZSC reached 98% and cracking selectivity was about 99%. Both catalysts were exhaustively characterized.This research is funded by Vietnam National Foundation for Science and Technology Development (NAFOSTED) under grant number 104.05-2014.21. CM aknowledges financial support by the Spanish Government-MINECO through "Severo Ochoa" (SEV 2012-0267) and CTQ2015-70126-R.Huyen, PT.; Nam, LTH.; Vinh, TQ.; Martínez, C.; Parvulescu, VI. (2018). ZSM-5/SBA-15 versus Al-SBA-15 as supports for the hydrocracking/hydroisomerization of alkanes. Catalysis Today. 306:121-127. https://doi.org/10.1016/j.cattod.2017.03.040S12112730

HybridMingler: Towards Mixed-Reality Support for Mingling at Hybrid Conferences

Mingling, the activity of ad-hoc, private, opportunistic conversations ahead of, during, or after breaks, is an important socializing activity for attendees at scheduled events, such as in-person conferences. The Covid-19 pandemic had a dramatic impact on the way conferences are organized, so that most of them now take place in a hybrid mode where people can either attend on-site or remotely. While on-site attendees can resume in-person mingling, hybrid modes make it challenging for remote attendees to mingle with on-site peers. In addressing this problem, we propose a collaborative mixed-reality (MR) concept, including a prototype, called HybridMingler. This is a distributed MR system supporting ambient awareness and allowing both on-site and remote conference attendees to virtually mingle. HybridMingler aims to provide both on-site and remote attendees with a spatial sense of co-location in the very same venue location, thus ultimately improving perceived presence

Photo-to-heat conversion of broadband metamaterial absorbers based on TiN nanoparticles under laser and solar illumination

We theoretically investigate photothermal heating of ultra-flexible metamaterials, which are obtained by randomly mixing TiN nanoparticles in polydimethylsiloxane (PDMS). Due to the plasmonic properties of TiN nanoparticles, incident light is perfectly absorbed in a broadband range (300-3000 nm) to generate heat within these metamaterials. Under irradiation of an 808 nm near-infrared laser with different intensities, our predicted temperature rises as a function of time agree well with recent experimental data. For a given laser intensity, the temperature rise varies non-monotonically with concentration of TiN nanoparticles because the enhancement of thermal conductivity and absorbed energy as adding plasmonic nanostructures leads to opposite effects on the heating process. When the model is extended to solar heating, photothermal behaviors are qualitatively similar but the temperature increase is less than 13 $K$. Our studies would provide good guidance for future experimental studies on the photo-to-heat conversion of broadband perfect absorbers.Comment: 8 pages, 7 figures, accepted for publications in Materials Today Communication

EFFECT OF VISCOUS HEAT GENERATION ON TEMPERATURE OF RAREFIED GAS MICROFLOWS DRIVEN BY MOVING SURFACE

Good understanding of the gas flow under rarefied conditions is important for designing the micro-electro-mechanical systems. The Navier-Stokes-Fourier equations with the slip and jump conditions can capture the rarefied gas flows in the slip regime. In this paper, we focus on evaluating new type of the Smoluchowski jump condition that was recently proposed in our previous work by considering the viscous heat generation. It was validated for external highspeed rarefied gas flows over the stationary surface. Our investigation is undertaken for internal rarefied gas microflows past the moving surfaces. The lid driven microcavity and Couette cases are adopted for this investigation with Knudsen number ranging from 0.05 to 1, the surface velocity varying from 50 m/s to 200 m/s, and argon as working gas. All simulations are run within the OpenFOAM framework. The gas temperatures along the moving surface and those across the microchannel predicted by new type of the Smoluchowski jump condition are close to the DSMC and R13-moment data in all cases considere

Unifying CP violations of quark and lepton sectors

A preliminary determination of the Dirac phase in the PMNS matrix is \dell\approx -\frac{\pi}{2}. A rather accurately determined Jarlskog invariant $J$ in the CKM matrix is close to the maximum. Since the phases in the CKM and PMNS matrices will be accurately determined in the future, it is an interesting problem to relate these two phases. This can be achieved in a families-unified grand unification if the weak CP violation is introduced spontaneously {\it \`a la} Froggatt and Nielsen at a high energy scale, where only one meaningful Dirac CP phase appears.Comment: 10 pages with 3 figure