Tiny Difference Research Articles

Discovery reach for wino and higgsino dark matter with a disappearing track signature at a 100 TeV pp collider

Within the theory of supersymmetry, the lightest neutralino is a dark matter candidate and is often assumed to be the lightest supersymmetric particle (LSP) as well. If the neutral wino or higgsino is dark matter, the upper limit of the LSP mass is determined by the observed relic density of dark matter. If the LSP is a nearly-pure neutral state of the wino or higgsino, the lightest chargino state is expected to have a significant lifetime due to a tiny mass difference between the LSP and the chargino. This article presents discovery potential of the 100 TeV future circular hadron collider (FCC) for the wino and higgsino dark matter using a disappearing-track signature. The search strategy to extend the discovery reach to the thermal limits of wino/higgsino dark matter is discussed with detailed studies on the background rate and the reference design of the FCC-hadron detector under possible running scenarios of the FCC-hadron machine. A proposal of modifying the detector layout and several ideas to improve the sensitivity further are also discussed.

Design of a three degrees-of-freedom biomimetic microphone array based on a coupled circuit

Inspired by the fly Ormia ochracea, a miniature sound source localization sensor was developed by designing a three degrees-of-freedom biomimetic microphone array, which uses the mechanical-circuit equivalent theory and realizes the location of the azimuth angle. The sensor is based on a coupled circuit, which receives three signals with only a tiny phase difference and produces three signals with an obvious intensity difference. The response sensitivity can be adjusted through the coupled circuit parameters. The experimental results indicate that the equivalent analog circuit sensor can effectively locate sound sources. At the same time, it can cope with various occasions by changing its circuit parameters conveniently. The designed system has significant advantages in various applications where the microphone array size is limited to localize the low frequency sound sources.

A theoretical exploration on why the replacement of hexyl group by alkoxycarbonyl in P3HT could greatly improve the performance of non-fullerene organic solar cell

• A comparation between P3HT and PDCBT with a tiny structure difference were investigated based on MD simulations and DFT calculations in non-fullerene OSCs. • V OC , absorption spectra, and the hole mobility which is in relation to the ability of charge transport were researched in depth. • By considering both of electron and hole transfer processes, the interface CS/CR rates were calculated. The PDCBT shows much better performance than P3HT in non-fullerene organic solar cell although the former only replaces hexyl by alkoxycarbonyl group compared with the latter. In this work, we will focus on this tiny difference in structure and huge difference in performance between these two polymers from theoretical perspective. Thus we present a comparative study based on the dependent/time-dependent density functional theory (DFT/TDDFT) calculations and molecular dynamic (MD) simulations. The results reveal that PDCBT not only possesses lower molecular orbital energy levels which leads to the increasement of the open circuit voltage ( V OC ), but also exhibits better planarity and larger hole mobility than P3HT . In particular, comparing with P3HT system, PDCBT system also displays the higher charge separation rate and smaller charge recombination rate both in hole transfer and electron transfer process at the interface, which promote the enhancement of short-circuit current density. Therefore, this work provides a fundamental understanding of the prominent influence of the replacement of hexyl group by alkoxycarbonyl in P3HT on the cell performance and also provides some theoretical guidance for further optimization of donor materials in non-fullerene organic solar cells (OSCs).

Global sensitivity analysis of static characteristics of tilting-pad journal bearing to manufacturing tolerances

A tiny difference between nominal dimension and actual processing dimension in the range of manufacturing tolerance can vary the performance of journal bearing. For minimizing this variation, sensitivity analysis is usually conducted. In present paper, the variance-based global sensitivity analysis was introduced to deal with the uncertainty quantification problem for a five-pad journal bearing. By using Fourier Amplitude Sensitivity Test (FAST) method, the first-order sensitivity indices of static characteristics including capacity, power loss and inlet flow were analyzed and evaluated for five normal distributed processing parameters: pad internal radius, shaft radius, pivot radius, pivot position and pad angular extent. The FAST method was proved perfectly suited to the bearing model. The quantitative sensitivities of output to each input parameter were obtained.

The cancer incidence and mortality among children and adolescents during the period of 2010-2014 in Henan Province, China.

ObjectiveThe cancer etiology in children and adolescents is largely different with that in adults, and the description in epidemiology still remains deficiency. Therefore, we described the cancer incidence and related epidemiological features in children and adolescents to provide clues for etiological studies.MethodsCancer incidence stratified by age, gender, and areas was calculated using data extracted from population‐based cancer registries in Henan Province, China. All cancer among children aged 0‐19 years were reclassified according to category criteria of the International Classification of Childhood Cancer, 3rd Edition (ICCC‐3). Age‐standardized rate (WSR) was calculated using Segi's world standardized population by the direct method, and it was expressed per million person‐years.ResultsThe crude cancer incidence and mortality were 87.56 and 36.32 per million person‐years among children aged 0‐19 years, and the WSRs slightly changed compared with crude incidence and mortality, and they were 87.36 and 35.46 per million person‐years. Leukemia and central nervous system neoplasms (CNS) were the most common cancer categories both in children aged 0‐14 years and in adolescents aged 15‐19 years in regardless of gender and areas. Tiny difference of incidence and mortality existed in different age groups across 0‐14 years; however, they were higher in adolescents aged 15‐19 years than that in children aged 0‐14 years. Among children aged 0‐19 years, the cancer incidence and mortality were predominant in boys, and the sex ratio was 1.19; however, it was varied by diagnostic categories.ConclusionThis is the first study that described the cancer incidence and mortality among children aged 0‐19 in Henan Province, and it would help researchers to understand the burden and epidemiological characteristics of childhood cancer, and hence suggested clues for the etiological studies.

Research on Undetected Overheat Fault of the GIS Bus Bar Contacts Based on Infrared Thermal Imaging

The overheating problem of GIS contacts would lead to a major accident. Recently, it was found that the infrared thermal imager cannot detect the overheating fault timely in many cases. In order to solve the above issues, a temperature rise test platform of the 252 kV GIS bus bar was built, and the bus bar temperature field distribution under normal operation and fault conditions was obtained. Then a three-dimensional simulation model was established based on the experimental platform. With the use of the finite element method, the temperature distribution of the GIS bus bar were compared with the experimental data. Results show that the temperature rise at normal contact condition is very small. The temperature distribution of the three-phase conductor is basically the same. The temperature of the SF6 gas is tiny difference in the upper area of the GIS cavity while the SF6 gas temperature is significantly different in the area below the GIS cavity. The air temperature outside the shell gradually decreases from the top to the bottom along the vertical direction, with the highest temperature at the top and the lowest at the bottom. However, the contact temperature would rise greatly rapidly at poor contacts while the shell temperature changes very small. Therefore, the method of measuring the shell temperature by infrared thermal imager can only be applied to the relatively slow temperature rise process in the GIS, in which the slow change of the contact temperature can be reflected on the shell. On the contrary, this method cannot be applied to the fault with fast temperature rise, as the contact temperature changes cannot be reflected on the shell timely. The above research work could provide theoretical basis and data support for revealing the temperature distribution inside GIS and determining the most sensitive position of temperature monitoring.

The pricing kernel puzzle: A behavioral explanation

We show that if sophisticated institutional managers and individual investors perceive tail-risks differently, then a new explanation for the pricing kernel puzzle emerges. We show, by example, that even a tiny difference in tail-risk perception by the two investor types can explain the pricing kernel puzzle.

Quantum Entanglement & Special Relativity Connected with Everything from Neutrons, Dark Matter & Ocean Tides to Matrix Maths, Dark Energy & Higher Dimensions

A few years ago, I first posted these ideas of mine online as preprints and have been developing the details since then. The earliest record I can find about writing on Mobius strips and matrix mathematics in relation to higher dimensions is an article in May 2018. Early n July 2019, I started thinking deeply about the role of neutrons in atoms. Then later that month, I saw Karl Kruszelnicki, who's known as Dr. Karl, on TV talking about higher dimensions and neutron decay. This reminded me of my earlier writings - and I put together the present article combining neutrons with Mobius strips, quantum spin, Earth’s tides, M-sigma, Saturn’s moon Enceladus, geometry, matrix mathematics, dark matter, dark energy, and higher dimensions. It also seemed necessary to add thoughts about binary digits, topology, supersymmetry, and Wick rotation’s proposed function in Special Relativity and quantum entanglement. The matrix mathematics/matrix mechanics of 90+90 equalling either 180 or 90 can also be related to the stable and radioactive isotopes of iron. This bonus section was inspired by the astronomy/astrophysics course “Greatest Unsolved Mysteries of the Universe”. It was prepared by ANU (the Australian National University), was put on the Internet by edX, and the two presenters in the course’s videos are Dr. Paul Francis and Brian Schmidt (yes, the co-winner of the 2011 Nobel Prize for Physics himself). In the video “V5.8: 21 centimetre radiation and the first stars,” Brian said, “(To get emission from the hydrogen atom) we're going to have to resort to a little trick of quantum mechanics that is provided for the hydrogen atom, which is that the proton and electron within quantum mechanics have a spin. It's analogous to a top spinning. It turns out that the hydrogen atom has a different energy if those spins are in opposite directions. It turns out it actually has a lower energy and so you can have an energy transition when that flip occurs and a photon comes out.” Then Paul said, “It's a bit like having two bar magnets. If you have them with north pole to north pole, or north pole to south pole, you'll feel a different amount of force between them; a different energy between these two things. When these things are spinning the same way or the opposite way there's a little tiny energy difference between them.” The following explains analogy of quantum spin to maths’ matrix and how, using that analogy, the statements by Brian and Paul can be converted into a mathematical origin of electromagnetism and gravitation.

Silica Nano-particle Anneal Treatment and Its Effect on Chemical Mechanical Polishing

Introduction Chemical mechanical polishing is the only one technology to obtain global planarization, which is widely applied to polish silicon, copper dual damascene structure, high/low K dielectric materials, tungsten plugs, poly-silicon gates and shallow trench isolation structure. SiO2 is widely used as abrasive for its superior properties like stability, suspension property and low viscosity There are lots of studies on silica properties. However, the detailed silica surface, inner characteristic and its effect on polishing performance are still unclear. we must also explore the silica nano-particle tiny structure difference, so we designed an experiment that we anneal the colloid silica and re-dispersed it to analyze the variety of particles properties and its influences on CMP performance.

Viscoelastic change of block copolymer ion gels in a photo-switchable azobenzene ionic liquid triggered by light.

A photo-switchable ionic liquid solvent bearing an azobenzene moiety induced a viscoelastic change of block copolymer ion gels by light. ABA triblock copolymers having poly(phenethyl methacrylate) and poly(benzyl methacrylate) as A blocks exhibited opposite photoinduced rheological responses although they had only a tiny structural difference in the alkyl chain length.

Uncertainty Analysis of Two Copula-Based Conditional Regional Design Flood Composition Methods: A Case Study of Huai River, China

The issue of regional design flood composition should be considered when it comes to the analysis of multiple sections. However, the uncertainty accompanied in the process of regional design flood composition point identification is often overlooked in the literature. The purpose of this paper, therefore, is to uncover the sensibility of marginal distribution selection and the impact of sampling uncertainty caused by the limited records on two copula-based conditional regional design flood composition methods, i.e., the conditional expectation regional design flood composition (CEC) method and the conditional most likely regional design flood composition (CMLC) method, which are developed to derive the combinations of maximum 30-day flood volumes at the two sub-basins above Bengbu hydrological station for given univariate return periods. An experiment combing different marginal distributions was conducted to explore the former uncertainty source, while a conditional copula-based parametric bootstrapping (CC-PB) procedure together with five metrics (i.e., horizontal standard deviation, vertical standard deviation, area of 25%, 50%, 75% BCIs (bivariate confidence intervals)) were designed and employed subsequently to evaluate the latter uncertainty source. The results indicated that the CEC and CMLC point identification was closely bound up with the different combinations of univariate distributions in spite of the comparatively tiny difference of the fitting performances of seven candidate univariate distributions, and was greatly affected by the sampling uncertainty due to the limited observations, which should arouse critical attention. Both of the analyzed sources of uncertainty increased with the growing T (univariate return period). As for the comparison of the two proposed methods, it seemed that the uncertainty due to the marginal selection had a slight larger impact on the CEC scheme than the CMLC scheme; but in terms of sampling uncertainty, the CMLC method performed slightly stable for large floods, while when considering moderate and small floods, the CEC method performed better.

The complete mitochondrial genome of Fimbriaria fasciolaris (Hymenolepididae)

The complete mitochondrial genome of Fimbriaria fasciolaris is reported for the first time in this study. Its entire mitogenome is 13,543 bp in length, contained 12 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes, and 2 non-coding regions. The arrangement of the twelve PCGs was identical to that of most cestode mtDNA sequence. Among all the cestodes mitochondrial genomes consulted from GenBank database, there existed a tiny difference in the order of trnY, trnL1, trnL2, and trnS2. The phylogenetic analysis by Bayesian inference method shows that F. fasciolaris of this study was confirmed to be a member of family Hymenolepididae.

An Improved GMM-Based Algorithm With Optimal Multi-Color Subspaces for Color Difference Classification of Solar Cells

Automatic color classification for solar cells is challenging because of the tiny color difference and low contrast. To address this problem, a color feature selection and classification frame is proposed in this paper. First, an intuitive multi-color space feature performance evaluation scheme is presented to select the optimal color subspaces that help to enormously enlarge the tiny color difference of solar cell images. And the optimal color subspaces can also be illustrated by employing multi-color space visualization method with combinational Mosaic images. Second, a nine-dimensional feature vector consisting of mean, variance, and skewness in the three optimal subspaces is extracted by utilizing the serial fusion technique. Third, an improved Gaussian mixture model in supervised manner for color classification is proposed by employing a k-means method based on adjacent rules, which helps to eliminate isolated points and enhances the classification performance. Finally, experimental results show that the overall performance of the proposed method achieves 97.9%, and outperform other algorithms especially for the tiny color difference of solar cell images.

Perturbation theories behind thermal mode spectroscopy for high-accuracy measurement of thermal diffusivity of solids

ABSTRACTThermal mode spectroscopy (TMS) has been recently proposed for accurately measuring thermal diffusivity of solids from a temperature decay rate of a specific thermal mode selected by three-dimensional (anti)nodal information [Phys. Rev. Lett., 117, 195901 (2016)]. In this paper, we find out the following advantages of TMS by use of perturbation analyses. First, TMS is applicable to the measurement of high-thermal diffusivity with a small-size specimen. Second, it is less affected by thermally resistive films on a specimen in the sense that the resistance at the interface does not affect the first-order correction of thermal diffusivity. Third, it can perform doubly accurate measurement of the thermal diffusivity specified at a thermal equilibrium state even if the diffusivity depends on temperature in the sense that the measurement can be performed within tiny temperature difference from the given state and that the decay rate of the slowest decaying mode is not affected by the dependence.

A novel evaluation on fracture pressure in depleted shale gas reservoir

AbstractFracture pressure is the key parameter both for horizontal drilling and hydraulic fracturing in the shale gas reservoir. Reservoir depletion will push for the change of the fracture pressure. Previous studies showed that fracture pressure will be decreased with reservoir depletion, which is not suitable for the anisotropic shale gas reservoir. Aiming at resolving this problem, a novel evaluation was established, which can be used to evaluate the influence on fracture pressure of the reservoir depletion, the anisotropy, and the well inclination. The results showed that the fracture pressure will be increased for the strongly anisotropic reservoir with reservoir depletion, and the fracture pressure has a tiny difference between the various anisotropic reservoirs before reservoir depleted, but a larger difference will appear after reservoir depleted, at the later depletion period, the fracture pressure is higher for the stronger anisotropic one. When the anisotropy and the depletion are both the same, the fracture pressure for the higher deviated well is lower. The method and the results can provide a theoretical basis both for the drilling and hydraulic fracturing in depleted shale gas reservoir.

Simple Synthetic Molecular Hydrogels from Self-Assembling Alkylgalactonamides as Scaffold for 3D Neuronal Cell Growth.

In this work, we demonstrated that the hydrogel obtained from a very simple and single synthetic molecule, N-heptyl-galactonamide was a suitable scaffold for the growth of neuronal cells in 3D. We evidenced by confocal microscopy the presence of the cells into the gel up to a depth of around 200 μm, demonstrating that the latter was permissive to cell growth and enabled a true 3D colonization and organization. It also supported successfully the differentiation of adult human neuronal stem cells (hNSCs) into both glial and neuronal cells and the development of a really dense neurofilament network. So the gel appears to be a good candidate for neural tissue regeneration. In contrast with other molecular gels described for cell culture, the molecule can be obtained at the gram scale by a one-step reaction. The resulting gel is very soft, a quality in accordance with the aim of growing neuronal cells, that requires low modulus substrates similar to the brain. But because of its fragility, specific procedures had to be implemented for its preparation and for cell labeling and confocal microscopy observations. Notably, the implementation of a controlled slow cooling of the gel solution was needed to get a very soft but nevertheless cohesive gel. In these conditions, very wide straight and long micrometric fibers were formed, held together by a second network of flexible narrower nanometric fibers. The two kinds of fibers guided the neurite and glial cell growth in a different way. We also underlined the importance of a tiny difference in the molecular structure on the gel performances: parent molecules, differing by a one-carbon increment in the alkyl chain length, N-hexyl-galactonamide and N-octyl-galactonamide, were not as good as N-heptyl-galactonamide. Their differences were analyzed in terms of gel fibers morphology, mechanical properties, solubility, chain parity, and cell growth.

THE BAPTISM OF A PRODIGAL SON IN MARILYNNE ROBINSON’S GILEAD

As a contemporary American female writer, a devout Christian, Marilynne Robinson gets her religious thoughts fully manifested in her Gilead. The novel is actually a home epistle that an aged and ailing father Ames passes to his 7-year-old innocent son, which narrates the three priesthood generations’ life changes from the Civil War to 1956 by making use of Ames’s first-person narration. However, the outsider John Ames Boughton (Jack) has been subject to diverse academic interest, which proves that he dominates an important textual place. This research makes the priest Ames’s baptism for prodigal Jack as an entry point. Ames has baptized Jack and has to reluctantly confer the name “John Ames” to Jack under the request of his bosom friend Boughton. Due to Ames’s mixed feelings (jealousy) in addition to Jack’s own diverse prodigality, Ames does not want to accept Jack at all. With the focus on the tiny difference between the religious ritual baptism and the true meaning of baptism in the novel, this research aims to put forward that the priest Ames has dilemma in conveying the Bible doctrine “love your neighbors”. However, at the end of novel, after seeing the unacceptable prodigal’s love and responsibility toward his old father, colored wife and interracial son, Ames starts to introspect his inappropriate attitude toward Jack. Under the guidance of the divine epiphany, Ames is willing to accept Jack and to give Jack the spiritual consolation. By analyzing Ames’s inner conflicts between his own “covetise” and the divine epiphany—the developmental process of Ames’s acceptance of unacceptable prodigal godson, this paper hopes to argue that the last blessing Ames gives to Jack reveals that Ames’s divine epiphany overwhelms his human nature—covetise which enables him to accept even to love the unacceptable people or unpleasant things in life so as to make faith and spiritual pursuit truly become a part of contemporary life.

Revealing two radio-active galactic nuclei extremely near PSR J0437−4715

Newton's gravitational constant $G$ may vary with time at an extremely low level. The time variability of $G$ will affect the orbital motion of a millisecond pulsar in a binary system and cause a tiny difference between the orbital period-dependent measurement of the kinematic distance and the direct measurement of the annual parallax distance. PSR J0437$-$4715 is the nearest millisecond pulsar and the brightest at radio. To explore the feasibility of achieving a parallax distance accuracy of one light-year, comparable to the recent timing result, with the technique of differential astrometry, we searched for compact radio sources quite close to PSR J0437$-$4715. Using existing data from the Very Large Array and the Australia Telescope Compact Array, we detected two sources with flat spectra, relatively stable flux densities of 0.9 and 1.0 mJy at 8.4 GHz and separations of 13 and 45 arcsec. With a network consisting of the Long Baseline Array and the Kunming 40-m radio telescope, we found that both sources have a point-like structure and a brightness temperature of $\geq$10$^7$ K. According to these radio inputs and the absence of counterparts in the other bands, we argue that they are most likely the compact radio cores of extragalactic active galactic nuclei rather than Galactic radio stars. The finding of these two radio active galactic nuclei will enable us to achieve a sub-pc distance accuracy with the in-beam phase-referencing very-long-baseline interferometric observations and provide one of the most stringent constraints on the time variability of $G$ in the near future.

Polarizer-free two-pixel polarimetric camera by compressive sensing.

We propose an original concept of compressive sensing (CS) polarimetric imaging based on a digital micromirror (DMD) array and two single-pixel detectors, without using any polarizer. The polarimetric sensitivity of the proposed setup is due to the tiny difference in Fresnel's coefficients of reflecting mirrors, which is exploited here to form an original reconstruction problem including a CS problem and a source-separation task. We show that a two-step approach, tackling each problem successively, is outperformed by a dedicated combined reconstruction method, which is demonstrated in this paper and preferably implemented through a reweighted fast iterative shrinkage-thresholding algorithm. The combined reconstruction approach is then further improved by including physical constraints specific to the polarimetric imaging context considered, which are implemented in an original constrained generalized forward-backward algorithm. Numerical simulations demonstrate the efficiency of the two-pixel CS polarimetric imaging setup at retrieving polarimetric contrast data with significant compression rate and good reconstruction quality. The influence of experimental imperfections of the DMD is also analyzed through numerical simulations, and 2D polarimetric imaging reconstruction results are finally presented.

Single-Molecule Nanocatalysis of Pt Nanoparticles

Because of the inhomogeneous structure of nanoparticles, many underlying catalytic details of these catalysts are hidden in the ensemble-averaged measurements. The single-molecule approach enables studying the catalytic behavior of nanoparticles at the single-particle level in single-turnover resolution. Here, on the basis of such a method, we study the catalytic behaviors of individual Pt nanoparticles to reveal the catalytic properties of nanoparticles of the product formation and desorption process. It is found that the catalytic reaction on Pt nanoparticles follows competitive mechanism in product formation process, while the product desorption process shows no selectivity between the indirect and direct desorption pathways. Moreover, the dynamic heterogeneity of Pt nanoparticles in product formation and desorption process is revealed to be due to the catalysis-induced surface restructuring. Surprisingly, it is found both experimentally and theoretically that the tiny difference in substrate molecules could lead to a huge difference in surface restructuring even on the same type of nanoparticle.