Acoustic detection of air shower cores

At an altitude of 1890m, a pre-test with an Air shower (AS) core selector and a small acoustic array set up in an anechoic pool with a volume of 20x7x7 cu m was performed, beginning in Aug. 1984. In analyzing the waveforms recorded during the effective working time of 186 hrs, three acoustic signals which cannot be explained as from any source other than AS cores were obtained, and an estimation of related parameters was made

Deep Learning Based Vehicle Make-Model Classification

This paper studies the problems of vehicle make & model classification. Some of the main challenges are reaching high classification accuracy and reducing the annotation time of the images. To address these problems, we have created a fine-grained database using online vehicle marketplaces of Turkey. A pipeline is proposed to combine an SSD (Single Shot Multibox Detector) model with a CNN (Convolutional Neural Network) model to train on the database. In the pipeline, we first detect the vehicles by following an algorithm which reduces the time for annotation. Then, we feed them into the CNN model. It is reached approximately 4% better classification accuracy result than using a conventional CNN model. Next, we propose to use the detected vehicles as ground truth bounding box (GTBB) of the images and feed them into an SSD model in another pipeline. At this stage, it is reached reasonable classification accuracy result without using perfectly shaped GTBB. Lastly, an application is implemented in a use case by using our proposed pipelines. It detects the unauthorized vehicles by comparing their license plate numbers and make & models. It is assumed that license plates are readable.Comment: 10 pages, ICANN 2018: Artificial Neural Networks and Machine Learnin

International Trade in Natural Gas: Golden Age of LNG?

The introduction of liquefied natural gas (LNG) as an option for international trade has created a market for natural gas where global prices may eventually be differentiated by the transportation costs between world regions. LNG’s trade share in 2013 was only about 30 percent of the total global trade in natural gas, but use of LNG is on the rise with numerous projects in planning or construction stages. Considering LNG projects that are under construction, planned, or proposed, we provide an analysis of LNG prospects for the next decade. LNG has substantial unexploited potential in terms of reducing capital requirements (especially for liquefaction projects), expanding new technology frontiers (e.g. floating LNG), serving new markets, and establishing new pricing schemes that better reflect the fundamentals of supply and demand. Trade volumes are projected to increase from about 240 Mt LNG in 2013 to about 340–360 Mt LNG in 2021. Despite potential challenges from weaker demand in Asia, longer-term projections show that LNG trade is bound to show substantial growth, partially due to geopolitical tensions that might increase LNG flows to Europe. However, these perspectives largely depend on demand choices, the availability and evolution of alternative fuels (e.g. renewable energies), and—most importantly—political decisions framing economic behavior.We thank The Cyprus Research Promotion Foundation for their support of this study. The interim report focused on the economics of project development options is available at: https://mitei.mit.edu/publications/reports-studies/interim-report-study-natural-gas-monetization-pathways-cyprus. This study was conducted by the MIT Energy Initiative and the MIT Joint Program on the Science and Policy of Global Change, where the authors are employed. MIT Energy Initiative is supported by its members listed at: http://mitei.mit.edu. The MIT Joint Program on the Science and Policy of Global Change is supported by a consortium of government, industry and foundation sponsors listed at http://globalchange.mit.edu/sponsors/current.html. Funding for this study is provided solely by The Cyprus Research Promotion Foundation. While Eni S.p.A. and Total are members of the MIT Energy Initiative, sponsors of the MIT Joint Program, and have exploration interests in Cyprus as described in the interim report, they have not contributed to any input, output, or funding related to this research. The views and opinions expressed in this report are those of the authors

Fractional Quantum Hall Effect in Suspended Graphene: Transport Coefficients and Electron Interaction Strength

Strongly correlated electron liquids which occur in quantizing magnetic fields reveal a cornucopia of fascinating quantum phenomena such as fractionally charged quasiparticles, anyonic statistics, topological order, and many others. Probing these effects in GaAs-based systems, where electron interactions are relatively weak, requires sub-kelvin temperatures and record-high electron mobilities, rendering some of the most interesting states too fragile and difficult to access. This prompted a quest for new high-mobility systems with stronger electron interactions. Recently, fractional-quantized Hall effect was observed in suspended graphene (SG), a free-standing monolayer of carbon, where it was found to persist up to T=10 K. The best results in those experiments were obtained on micron-size flakes, on which only two-terminal transport measurements could be performed. Here we pose and solve the problem of extracting transport coefficients of a fractional quantum Hall state from the two-terminal conductance. We develop a method, based on the conformal invariance of two-dimensional magnetotransport, and illustrate its use by analyzing the measurements on SG. From the temperature dependence of longitudinal conductivity, extracted from the measured two-terminal conductance, we estimate the energy gap of quasiparticle excitations in the fractional-quantized nu=1/3 state. The gap is found to be significantly larger than in GaAs-based structures, signaling much stronger electron interactions in suspended graphene. Our approach provides a new tool for the studies of quantum transport in suspended graphene and other nanoscale systems

A study on inclusion formation mechanism in alpha-LiIO sub 3 crystals

The spatial distribution of inclusions in alpha-LiIO3 crystals by means of an argon laser beam scanning technique is studied. The effects of crystal dimensions and solution fluid flow on the inclusion formation in the alpha-LiIO3 crystals were observed. It was further shown that the fluid flow plays an important role in the formation of inclusions. The results obtained were further applied and verified by growing a perfect alpha-LiIO3 single crystal. An experimental foundation for further theoretical studies on the causes of inclusions may be provided

Charmless two-body B decays: A global analysis with QCD factorization

In this paper, we perform a global analysis of $B \to PP$ and $PV$ decays with the QCD factorization approach. It is encouraging to observe that the predictions of QCD factorization are in good agreement with experiment. The best fit $\gamma$ is around $79^\circ$. The penguin-to-tree ratio $|P_{\pi \pi}/T_{\pi \pi}|$ of $\pi^+ \pi^-$ decays is preferred to be larger than 0.3. We also show the confidence levels for some interesting channels: $B^0 \to \pi^0 \pi^0$, $K^+ K^-$ and $B^+ \to \omega \pi^+$, $\omega K^+$. For $B \to \pi K^\ast$ decays, they are expected to have smaller branching ratios with more precise measurements.Comment: 20 pages, 4 figures, version to appear in Phys. Rev.

Hybrid Superpixel Segmentation

Poster presentation: paper no. 27postprin