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the mean value concept in mono-linear regression of multi-variables and its application to trace studies in geosciences

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Science China Earth Sciences 2007年第12期50卷 1828-1834页

作者： A J t JULL NSF-AMS laboratory University of Arizona

the "mean value concept" in a mono-linear regression of multi-variables is *** applications to reconstruction of the past 90-year salinity of the sea surface water in Xisha Islands and to tracing the past 80 ka paleo-geomagnetic events from the Luochuan loess 10Be record are introduced in detail,which show the significance and the potential of the "mean value concept" in geoscience research.

关键词： mean value concept, linear regression, trace, reconstruction

thermobaric and enhanced blast explosives(tBX and EBX)

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Defence technology（防务技术） 2016年第6期12卷 423-445页

作者： Lemi tüRKER Department of Chemistry Middle East Technical University

In this review, excerpts from the literature of thermobaric(tBX) and enhanced blast explosives(EBX) that are concentrated on studies that include their compositions, properties, reactive metal components, modeling and... 详细信息

关键词： thermobaric explosives Enhanced blast explosives Reactive metals High explosives Explosives

Modelling of Energy Storage Photonic Medium by Wavelength-Based Multivariable Second-Order Differential Equation

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Computer Modeling in Engineering & Sciences 2020年第4期123卷 333-351页

作者： t.Binesh Government Model Engineering College Ernakulam682021India

Wavelength-dependent mathematical modelling of the differential energy change of a photon has been performed inside a proposed hypothetical optical *** existence of this medium demands certain mathematical constraints,which have been derived in *** reverse modelling,a medium satisfying the derived conditions is proven to store energy as the photon propagates from the entry to exit point.A single photon with a given intensity is considered in the analysis and hypothesized to possess a definite non-zero probability of maintaining its energy and velocity functions analytic inside the proposed optical medium,despite scattering,absorption,fluorescence,heat generation,and other nonlinear *** energy and velocity functions are thus singly and doubly differentiable with respect to *** solution of the resulting second-order differential equation in two variables proves that energy storage or energy flotation occurs inside a medium with a refractive index satisfying the described mathematical *** minimum-value-normalized refractive index profiles of the modelled optical medium for transformed wavelengths both inside the medium and for vacuum have been *** proofs,design equations,and detailed numerical analyses are presented in the paper.

关键词： Optical medium modelling energy storage multivariable second order differential equation numerical analysis minimum value-normalized refractive index profile

trans-dinitroglycoluril isomers-A DFt treatment

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Defence technology（防务技术） 2017年第1期13卷 6-15页

作者： Lemi türker Middle East technical University Department of ChemistryAnkaraTurkey

Isomers of trans-1,4-Dinitroglycoluril(trans-DINGU) and their 1,3-tautomers are considered within the constraints of B3LYP/6-31ttG(d,p) and B3LYP/CC-PVtZ levels of DFt calculations. Additionally, the interactions of these isomers and proton in vacuum are investigated. the data have revealed that two of the three isomers undergo C — H bond cleavage as the result of interaction with proton in vacuum. the total energies, some structural properties, the calculated IR and UV spectra are discussed.

关键词： trans-dinitroglycoluril DINGU Nitramines DFt calculations Protonation tautomerism

the evolution and refinement of vasoepididymostomy techniques

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Asian Journal of Andrology 2013年第1期15卷 49-55页

作者： Peter t Chan Department of Urology Royal Victoria Hospital McGill University Health Center Montreal Quebec H3A 1A1 Canada

Obstructive azoospermia secondary to epididymal obstruction can be corrected by microsurgical reconstruction with vasoepididymostomy （VE）. Although alternative management such as epididymal or testicular sperm aspiration in conjunction with intracytoplasmic sperm injection is feasible, various studies have established the superior cost-effectiveness of VE as a treatment of choice. Microsurgical VE is considered one of the most technically challenging microsurgeries. Its success rate is highly dependent on the skills and experience of the surgeons. Various techniques have been described in the literature for VE. We have pioneered a technique known as longitudinal intussusception VE （LIVE） in which the epididymal tubule is opened longitudinally to obtain a larger opening to allow its tubular content to pass through the anastomosis. Our preliminary data demonstrated a patency rate of over 90%. this technique has been widely referenced in the recent literature including robotic-assisted microsurgery. the history of the development of different VE approaches, the oreoDerative evaluation along with the techniaues of various VE will be described in this article.

关键词： longitudinal intussusception vasoepididymostomy (LIVE) intracytoplasmic sperm injection (ICSI) male infertility microsurgery obstructive azoospermia vasoepididymostomy (VE)

Acoustic band gaps in two-dimensional square arrays of semi-hollow circular cylinders

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Science China(technological Sciences) 2009年第2期52卷 303-312页

作者： t. Kim MOE Key Laboratory for Strength and Vibration School of Aerospace Xi'an Jiaotong University

Concave surfaces focus sound while convex surfaces disperse sound. It is therefore interesting to know if it is possible to make use of these two opposite characteristics to enhance the band gap performance of periodic arrays of solid cylinders in air. In this paper, the band gap characteristics of a 2-D square array of semi-hollow circular cylinders embedded in air are investigated, both experimentally and theoretically. In comparison with the types of inclusion studied by previous researchers, a semi-hollow circular cylinder is unique in the sense that it has concave inner surfaces and convex outer surfaces. the finite difference time domain (FDtD) method is employed to study the propagation behavior of sound across the new phononic crystal of finite extent, and the influences of sample size and inclusion orientation on band gap characteristics are quantified in order to obtain the maximum band gap. For reference, the band gap behaviors of solid circular cylinder/air and hollow circular cylinder/air systems are considered and compared with those of semi-hollow circular cylinder/air systems. In addition to semi-hollow circular cylinders, other inclusion topologies such as semi-hollow triangular and square cylinders are also investigated. to validate the theoretical predictions, experimental measurements on square arrays of hollow Al cylinders in air and semi-hollow Al cylinders in air are carried out. the results demonstrate that the semi-hollow circular cylinder/air system has the best overall band gap performance.

关键词： phononic crystals PDtD semi-hollow circular cylinders band gaps experimental verification

Hollow dimension of modules

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2005年第10期6卷 1055-1057页

作者： ORHAN Nil KESKiN tütüNCü Derya Department of Mathematics University of HacettepeBeytepe 06532 AnkaraTurkeyDepartment of Mathematics University of Hacettepe Beytepe 06532 AnkaraTurkey

In this paper, we are interested in the following general question： Given a module Mwhich has finite hollow dimension and which has a finite collection of submodules Ki （ 1≤i≤n） such that M=K1 ＋... ＋Kn can we find an expression for the hollow dimension of Min terms of hollow dimensions of modules built up in some way from Kt… ,Kn？ We prove the following theorem： Let Mbe an amply supplemented module having finite hollow dimension and let Ki （ 1 ≤i≤n） be a finite collection of submodules of M such that M=K1 ＋... ＋Kn. then the hollow dimension h（M） of M is the sum of the hollow dimensions of Ki （1≤i≤n） if and only if Ki is a supplement of K1＋...＋K（i-1）＋K（i＋1）＋...＋Kn in M for each 1≤i≤n.

关键词： Hollow dimension Supplement submodule

Numerical damage evaluation of perforated steel columns subjected to blast loading

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Defence technology（防务技术） 2022年第5期18卷 735-746页

作者： Mahmoud t.Nawar Ibrahim t.Arafa Osama M.Elhosseiny Structural Engineering Department Zagazig UniversityZagazig44519Egypt

the structural performance of perforated steel columns(PSCs)is significantly more complex than the one of solid web I-shaped elements under the diversity of blast loading *** damage criterion of PSCs is not only related to initial deformation response during the blast but also the residual axial load capacity and it can be considered as a reliable index after the blast ***,the PSCs damages will be studied in two stages;direct and post blast *** the present study,the dynamic response of PSCs was numerically evaluated under different levels of blast threats using LS-DYNA *** explicit finite element(FE)analyses are carried out to investigate the effect of various parameters,such as web opening shapes,boundary conditions and strengthening details on the damage index and toughness of the PSCs compared to the parent steel *** results of the comparative study show that the damage and toughness decrease when the support condition changes from pinned to fixed ends through the two stages of *** give high toughness compared to its parent sections during blast shock stage while,a remarkable decrease in toughness is observed during the application of axial gravity after blast ***,the web opening shapes have slight effects on the global dynamic behavior of PSCs,particularly in terms of residual *** the contrary,the retrofitting strategy using both closed holes at end and vertical stiffeners have an effective enhancement to get higher toughness in case of the extreme blasts.

关键词： Perforated steel columns Blast load Damage criterion Numerical modeling Explicit finite element analysis Web-opening shapes

Indium antimonide based HEMt for RF applications

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Journal of Semiconductors 2014年第11期35卷 20-22页

作者： t.D.Subash t.Gnanasekaran K.N.S.K College of Engineering Nagercoil-629901India RMK College of Engineering and technology Tamil Nadu601206India

We report on an indium antimonide high electron mobility transistor with record cut-off frequency characteristics. For high frequency response it is important to minimize parasitic resistance and capacitance to improve short-channel effects. For analog applications adequate pinch-off behavior is demonstrated. For proper device scaling we need high electron mobility and high electron density. toward this end, the device design features and simulation are carried out by the Synopsys tCAD tool. A 30 nm InSb HEMt exhibits an excellent cut-off frequency of 586 GHz. to the knowledge of the authors, the obtained cut-off frequency is the highest ever reported in any FEt on any material system.

关键词： HEMt InSb gate length cut-off frequency short-channel effects