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Text Indexing for Long Patterns: Anchors are All you Need
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The source code, data, and/or other artifacts have been made available at https://github.com/lorrainea/BDA- index.Copyright © 2023 the owner/author(s). In many real-world database systems, a large fraction of the data is represented by strings: sequences of letters over some alphabet. This is because strings can easily encode data arising from different sources. It is often crucial to represent such string datasets in a compact form but also to simultaneously enable fast pattern matching queries. This is the classic text indexing problem. The four absolute measures anyone should pay attention to when designing or implementing a text index are: (i) index space; (ii) query time; (iii) construction space; and (iv) construction time. Unfortunately, however, most (if not all) widely-used indexes (e.g., suffix tree, suffix array, or their compressed counterparts) are not optimized for all four measures simultaneously, as it is difficult to have the best of all four worlds. Here, we take an important step in this direction by showing that text indexing with locally consistent anchors (lc-anchors) offers remarkably good performance in all four measures, when we have at hand a lower bound l on the length of the queried patterns --- which is arguably a quite reasonable assumption in practical applications. Specifically, we improve on the construction of the index proposed by Loukides and Pissis, which is based on bidirectional string anchors (bd-anchors), a new type of lc-anchors, by: (i) designing an average-case linear-time algorithm to compute bd-anchors; and (ii) developing a semi-external-memory implementation to construct the index in small space using near-optimal work. We then present an extensive experimental evaluation, based on the four measures, using real benchmark datasets. The results show that, for long patterns, the index constructed using our improved algorithms compares favorably to all classic indexes: (compressed) suffix tree; (compressed) suffix array; and the FM-index.European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreements No 872539 and 956229, respectively; and by UKRI through REPHRAIN (EP/V011189/1)
Gas Sensors Based on Conducting Polymers
Since the discovery of conducting polymers (CPs), their unique properties and tailor-made structures on-demand have shown in the last decade a renaissance and have been widely used in fields of chemistry and materials science. The chemical and thermal stability of CPs under ambient conditions greatly enhances their utilizations as active sensitive layers deposited either by in situ chemical or by electrochemical methodologies over electrodes and electrode arrays for fabricating gas sensor devices, to respond and/or detect particular toxic gases, volatile organic compounds (VOCs), and ions trapping at ambient temperature for environmental remediation and industrial quality control of production. Due to the extent of the literature on CPs, this chapter, after a concise introduction about the development of methods and techniques in fabricating CP nanomaterials, is focused exclusively on the recent advancements in gas sensor devices employing CPs and their nanocomposites. The key issues on nanostructured CPs in the development of state-of-the-art miniaturized sensor devices are carefully discussed. A perspective on next-generation sensor technology from a material point of view is demonstrated, as well. This chapter is expected to be comprehensive and useful to the chemical community interested in CPs-based gas sensor applications
Cauchy Problem for Fractional Ricatti Differential Equations Type with Alpha Order Caputo Fractional Derivatives
In this paper, we investigate solution of the fractional Ricatti differential equations (FRDEs) with alpha order Caputo fractional derivatives. In fact, FRDEs are analogous of the Ricatti ordinary differential equations. The multi power series method is used to obtain a useful formula that is implemented to find an explicit solution of Cauchy problem for FRDEs without solving any integral. This formula is explicit and easy to compute by using Maple software to get explicit solution. Also, it is shown that the proposed formula can be used to solve the Cauchy problem for Ricatti ordinary differential equations
Atmospheric transport of hydrogen sulfide from proposed geothermal power plant (unit 13). Predictions by physical modeling in a wind tunnel
CER76-77RLP-JEC-SA51.Prepared for Aminoil USA, Incorporated.Includes bibliographical references (page 32).April 1977
Circulation of vented gases around biomedical research facility
For the University of New Mexico.July 1979.CER79-80JEC-RLP-SSA18.Includes bibliographical references
Pedal towards Safety: The Development and Evaluation of a Risk Index for Cyclists †
Cyclists are at a higher risk of being involved in accidents. To this end, a safer environment for cyclists should be pursued so that they can feel safe while riding their bicycles. Focusing on safety risks that cyclists may face is the main key to preserving safe mobility, reducing accidents, and improving their level of safety during their travel. Identifying and assessing risk factors, as well as informing cyclists about them may lead to an efficient and integrated transportation system. Therefore, the purpose of this research is to introduce a risk index that can be adapted to different road areas in order to measure the degree of how risky these areas are for biking. Cyclists’ behavior and demographics were integrated into the risk index calculation. The methodology followed to obtain the risk index composed of four phases: risk factor identification, risk factor weighting, risk index formulation, and risk index validation. Nineteen risk factors are categorized into four major groups: facility features, infrastructure features, cyclist behavior, and weather and traffic conditions
Evidence for low-density lipoprotein–induced expression of connective tissue growth factor in mesangial cells
Evidence for low-density lipoprotein–induced expression of connective tissue growth factor in mesangial cells.BackgroundAlthough hyperlipidemia is a risk factor for the progression of renal damage, the relationship between increased plasma lipoproteins and glomerular injury is poorly defined. Connective tissue growth factor (CTGF) is emerging as a key determinant of progressive fibrotic diseases and its expression is up-regulated by diabetes. To define the mechanisms through which low-density lipoproteins (LDLs) promote glomerular injury, we evaluated whether LDL can modulate the expression of CTGF and collagen I.MethodsThe effects of LDL on CTGF and collagen I expression were carried out in rat mesangial cells.ResultsTreatment of mesangial cells with LDL for 24 hours produced a significant increase in the protein levels of CTGF and collagen I compared to unstimulated controls. To explore if CTGF and collagen I are downstream targets for regulation by transforming growth factor-β (TGF-β), mesangial cells were treated with various concentration of TGF-β for 24 hours. TGF-β produced a concentration-dependent increase in the protein levels of CTGF and collagen I. The increase in CTGF and collagen I induced by LDL was significantly inhibited by neutralizing anti-TGF-β antibodies. Inhibition of p38mapk or p42/44mapk activities did not affect LDL-induced TGF-β1, CTGF, and collagen I expression, whereas inhibition of c-Jun NH2-terminal kinase (JNK) suppressed LDL-induced TGF-β, CTGF, and collagen I expression.ConclusionThese findings implicate JNK pathway and TGF-β1 as key players in LDL signaling leading to CTGF and collagen I expression in mesangial cells. The data also point to a potential mechanistic pathway through which lipoproteins may promote glomerular injury
ELECTROMAGNETIC RADIATION SHIELDING PROPERTIES OF COPPER CONTAINING ACTIVATED CARBON
It's proposed to modify the consist and electromagnetic radiation shielding properties of powdery activated carbon by the method of chemical deposition of copper clusters on the surface of fractions of such material. The choice of these element caused by it resistance to the environment conditions, which could determines the stability of the shielding properties of materials including of these elements. Regularities of electromagnetic radiation interaction with powdery activated carbon modified by the proposed method were researched. According to the results of this research it's established that electromagnetic radiation reflection coefficient in frequency range 8…12 GHz of shields made with powdery activated carbon decreases from –2 to –14 dB after modification of such material consist.It's proposed to modify the consist and electromagnetic radiation shielding properties of powdery activated carbon by the method of chemical deposition of copper clusters on the surface of fractions of such material. The choice of these element caused by it resistance to the environment conditions, which could determines the stability of the shielding properties of materials including of these elements. Regularities of electromagnetic radiation interaction with powdery activated carbon modified by the proposed method were researched. According to the results of this research it's established that electromagnetic radiation reflection coefficient in frequency range 8…12 GHz of shields made with powdery activated carbon decreases from –2 to –14 dB after modification of such material consist
Ice-lens formation and geometrical supercooling in soils and other colloidal materials
We present a new, physically-intuitive model of ice-lens formation and growth
during the freezing of soils and other dense, particulate suspensions.
Motivated by experimental evidence, we consider the growth of an ice-filled
crack in a freezing soil. At low temperatures, ice in the crack exerts large
pressures on the crack walls that will eventually cause the crack to split
open. We show that the crack will then propagate across the soil to form a new
lens. The process is controlled by two factors: the cohesion of the soil, and
the geometrical supercooling of the water in the soil; a new concept introduced
to measure the energy available to form a new ice lens. When the supercooling
exceeds a critical amount (proportional to the cohesive strength of the soil) a
new ice lens forms. This condition for ice-lens formation and growth does not
appeal to any ad hoc, empirical assumptions, and explains how periodic ice
lenses can form with or without the presence of a frozen fringe. The proposed
mechanism is in good agreement with experiments, in particular explaining
ice-lens pattern formation, and surges in heave rate associated with the growth
of new lenses. Importantly for systems with no frozen fringe, ice-lens
formation and frost heave can be predicted given only the unfrozen properties
of the soil. We use our theory to estimate ice-lens growth temperatures
obtaining quantitative agreement with the limited experimental data that is
currently available. Finally we suggest experiments that might be performed in
order to verify this theory in more detail. The theory is generalizable to
complex natural-soil scenarios, and should therefore be useful in the
prediction of macroscopic frost heave rates.Comment: Submitted to PR
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