Low cost, practical, all-digital open-loop fiber-optic gyroscope

A novel all-digital scheme for open-loop fiber-optic gyroscope (POG), where only two key points of output wave were digitized directly, has been proposed. A control equation, with which the modulation depth of PZT modulator is stable when setting the modulation depth as 4.35 and a calculation equation, with which the Sagnac phase can be worked out, are derived. A modulation depth control and an automatic correlation sampling and a gain control technology were induced. A photo-type FOG was made and tested. The good performance was achieved.     

The CBM experiment—a status report

The CBM experiment is being designed to study strongly interacting matter at high densities with nuclear collisions up to 45 A GeV beam energy at the future FAIR centre. With interaction rates unprecedented in heavy-ion collisions, CBM will give access also to extremely rare probes and thus to the early stage of the collisions, in search for the first-order phase transition from confined to deconfinedmatter and the QCD critical point. The conceptual design of the experiment is consolidated, and the project has entered the R&D and technical design phase. We report on the project status, putting enphasis on recent progress and developments.     

Nanotechnology as an experiment in democracy: how do citizens form opinions about technology and policy?

This article analyzes nanotechnology as an experiment in democratic deliberation, one that seems motivated both by a desire to improve deliberative democracy and to protect the technology from undue public interference. However, rather than involving amplified (overstated) risks, nanotechnology appears to involve attenuated (understated) risks. Results from a 3-year panel study are presented to illustrate the ways in which citizens form opinions about nanotechnology, supporting the assertion that public opinion about complex technology can be both reasonable and stable. Nevertheless, the authors also voice concern that, in the absence of public pressure, risk regulation may not evolve as swiftly as it should to protect both society and industry.     

Is the electron a composite particle? An experiment

The crucial problem of physics was first formulated by Democritus in the 5th century BC: to find the or smallest uncuttable bits of matter. That has not changed ever since. Among the current candidates are electron and positron, the least expensive of today's bona fide . Experimental tests of their non-compositeness by precisely measuring the gyromagnetic ratios of the individual trapped particles are reviewed.You know, it would be sufficient to really understand the electron.Albert Einstein     

Source location in a wedge waveguide:deconvolution filter experiment

Source location experiments in a wedge waveguide were conducted totest a single channel time domain technique for a known source.The laboratorymeasurements were made in the air wedge having rigid sheet rock boundaries.Thewedge angle was 6.6°.The source transmitted a short oscillatory signal having afrequency band of 3—13 kHz.The distances of the source and receiver from thewedge apex were 1.75m and 3.75m respectively.The Biot-Tolstoy wedge solutionwas used for calculating the source to receiver impulse response.For the geometry,all the arrivals are due to images.The deconvolution filter is used.The output ofthe deconvolution filter is cross correlated with the known input signal.Maps ofpossible source locations are made by(1)assuming a trial source location,(2)computing a theoretical impulse response and the corresponding deconvolution fil-ter,(3)filtering the signal,and(4)mapping the peak absolute maximum of thedeconvolution filter output.The actual source location is correctly mapped.Thereare severa     

The LPCTrap experiment: measurement of the ��-��?angular?correlation in 6He+ decay using a transparent Paul trap

The LPCTrap experiment is devoted to the precise measurement of the ??-?? angular correlation parameter, a _?|? , in the pure Gamow-Teller decay of ⁶He⁺. This experiment is motivated by the search of the presence of tensor type contributions in the weak interaction. The radioactive source is confined in a transparent Paul trap installed at LIRAT, the low energy beam line of the SPIRAL facility. The ??-?? correlation is studied by measuring the time of flight of the recoil ions detected in coincidence with the ?? particles. During the last experiment, a total of 4 × 10⁶ coincidence events have been recorded which would enable to determine the coefficient with a statistical uncertainty of 0.5%. The status of the analysis is presented in this contribution.     

The mystical interlinks:Mechanics,religion or optics?

正The beauty of this world relies on a fact that there is always this or that mystical interlink among different fields,one concept in a specific realm shines out with great brilliancy in another totally different territory.Catenary is the curve that a free-hanging chain assumes under its own weight,which is thought to be atrue mathematical and mechanical     

The Cryptocurrency Market in Transition before and after COVID-19: An Opportunity for Investors?

We analyze the correlation between different assets in the cryptocurrency market throughout different phases, specifically bearish and bullish periods. Taking advantage of a fine-grained dataset comprising 34 historical cryptocurrency price time series collected tick-by-tick on the HitBTC exchange, we observe the changes in interactions among these cryptocurrencies from two aspects: time and level of granularity. Moreover, the investment decisions of investors during turbulent times caused by the COVID-19 pandemic are assessed by looking at the cryptocurrency community structure using various community detection algorithms. We found that finer-grain time series describes clearer the correlations between cryptocurrencies. Notably, a noise and trend removal scheme is applied to the original correlations thanks to the theory of random matrices and the concept of Market Component, which has never been considered in existing studies in quantitative finance. To this end, we recognized that investment decisions of cryptocurrency traders vary between bearish and bullish markets. The results of our work can help scholars, especially investors, better understand the operation of the cryptocurrency market, thereby building up an appropriate investment strategy suitable to the prevailing certain economic situation.     

The course of science and technology,and acoustics:past,present and future——turning to information acoustics

In this paper,the historical development of acoustics has been brieflyreviewed.It can be concluded that acoustics study has been developed alongwith the same atream of the historical developments of science and technology,the category of acoustics has changed from the naturc-oriented and passivephysical acoustics to the human-oriented and active information acoustics.Ithas been extended over a variety of wide fields.     

The Massachusetts Toxics Use Reduction Act: a model for nanomaterials regulation?

Polyvinylimidazole (PVIm)-grafted superparamagnetic iron oxide nanoparticles (SPION) (Si-PVIm-grafted Fe₃O₄ NPs) were prepared by grafting of telomere of PVIm on the SPION. The product identified as magnetite, which has an average crystallite size of 9?±?2?nm as estimated from X-ray line profile fitting. Particle size was estimated as 10.0?±?0.5?nm from TEM micrographs. Mean particle size is found as 8.4?±?1.0?nm which agrees well with the values calculated from XRD patterns (9?±?2?nm). Vibrating Sample Magnetometer (VSM) analysis explained the superparamagnetic nature of the nanocomposite. Thermogravimetric analysis showed that the Si-Imi is 25?% of the Si-PVIm-grafted SPION, which means an inorganic content is about 75?%. Detailed electrical and dielectric properties of the properties of the product are also presented. The conductivity of the sample increases significantly with temperature and has the value in the range of 1.14?×?10^?7?C1.78?×?10^?4?S?cm^?1. Analysis of the real and imaginary parts of the permittivities indicated temperature and frequency dependency representing interfacial polarization and temperature-assisted reorganization effects.     

The structure of liquid methanol revisited: a neutron diffraction experiment at −80 °C and +25 °C

Pulsed neutron diffraction with isotope substitution on the hydroxyl hydrogens (H) is used to study the structure of pure liquid methanol at ?80 °C and +25 °C. Although this liquid has been studied with neutrons several times in the past this is the first time that the composite partial structure factors, XX, XH and HH, are derived from the diffraction data. Here X represents a weighted sum of correlations from carbon (C), oxygen (O), and methyl hydrogen (M) atoms on the methanol molecule. The data are used in an empirical potential structure refinement (EPSR) computer simulation of the liquid at both temperatures. Model distributions of molecules consistent with these data are used to estimate the individual site—site radial distribution functions, the coefficients of the spherical harmonic expansion of the orientational pair correlation function, and the length of possible chains of methanol molecules formed in the liquid. Although the results are qualitatively similar to those of earlier computer simulation studies of this liquid, they do differ in detail from previous work. In particular, although most molecules in the liquid are found as part of chains up to 10 molecules long, the average chain length is only about 2.7 molecules at both temperatures, there are about 1.3 hydrogen bonds per molecule on average, and the chains are highly nonlinear on average.     

The antiproton cell experiment—do antiprotons offer advantages over other particle beam modalities?

The use of heavy charged particles for cancer therapy has the potential for a significant improvement of the therapeutic window compared to standard X-ray treatments. This is due to the improved energy deposition profile, exhibiting a well-defined peak at a depth in target controllable by the initial energy of the beam. Particles heavier than protons in addition show an increase in biological effectiveness. Compared to protons or heavy ions, antiprotons deposit additional annihilation energy, mostly by low energy recoils, resulting in an increase of dose and also adding a component with high biological effectiveness in the target region. The relative magnitude of the physical energy deposition of antiprotons compared to protons was measured at Low Energy Antiproton Ring (LEAR) by A. Sullivan, but no study of the biological effect had been conducted prior to the Antiproton Cell Experiment (AD-4/ACE) experiment at CERN. The special conditions found at CERN present significant challenges, but also offer unique opportunities. 500?ns pulses of antiprotons are extracted from the Antiproton Decelerator (AD) at 500?MeV/c momentum. Biological cell samples are irradiated and clonogenic survival fractions are measured for various doses. To extract biological efficiency, the physical dose deposition is obtained by Monte-Carlo calculations in conjunction with shot-by-shot monitoring of the incoming beam intensity and profile using a silicon pixel detector. Also imaging of the pions resulting from antiproton annihilations in the target using silicon pixel detector technology to determine the actual range in more complex targets with strong variations in material densities was carried out. The feasibility of this technique using a novel arrangement of the detector was demonstrated. This paper describes the ACE experiment and focuses on the different detector activities within the AD-4/ACE collaboration, explaining the experimental set-up, physical and biological methods used, recent results, and future plans.     

The Roton Minimum: Is it a General Feature of Strongly Correlated Liquids?

The roton minimum is a deep minimum in the collective excitation spectrum of the liquid, forming around fairly high k ‐values. We have discovered, through MD simulations, that this appears to be a general feature of strongly coupled liquids and is ubiquitous in 2D and 3D Yukawa liquids. We suggest that the physical origin of the roton minimum has to be sought in the quasi‐localization of particles in a strongly correlated liquid and in the ensuing formation of local microcrystals whose averaged frequency dispersion would show roton minimum‐like feature (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

The state vector of a quantum system: Mathematical fiction or physical reality?

A version of an experiment with a correlated pair of entangled particles is considered. This experiment demonstrates an interesting effect of variations in the entangled photon polarization that shows the reality of all of the various superposition components and the corresponding state vector of the quantum system. The possible consequences of this are analyzed.     

Is econophysics a new discipline? The neopositivist argument

Econophysics is a new approach which applies various models and concepts associated with statistical physics to economic (and financial) phenomena. This field of research is a new step in the history and the evolution of Physics Sciences and the question about the disciplinary characteristics of this field must be asked. At first glance, it might appear that economics and econophysics share the same subject of research (that of analysis of economic reality). In this paper I will use neopositivism to show that econophysics is methodologically very different from economics and that it can be considered as a separate discipline. The neopositivist framework provides econophysics with some arguments for rejecting mainstream economics.