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A survey on the Metaheuristics for Cryptanalysis of Substitution and Transposition Ciphers

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Computer Systems Science & Engineering 2021年第10期39卷 87-106页

作者： Arkan kh Shakr Sabonchi Bahriye Akay Computer Engineering Department Erciyes UniversityKayseri38039MelikgaziTurkey

This paper presents state-of-art cryptanalysis studies on attacks of the substitution and transposition ciphers using various metaheuristic *** cryptanalysis methods employ an exhaustive search,which is computationally ***,metaheuristics have attracted the interest of researchers in the cryptanalysis *** algorithms are known for improving the search for the optimum solution and include Genetic Algorithm,Simulated Annealing,Tabu Search,Particle Swarm Optimization,Differential Evolution,Ant Colony,the Artificial Bee Colony,Cuckoo Search,and Firefly *** most important part of these various applications is deciding the fitness function to guide the *** review presents how these algorithms have been implemented for cryptanalysis *** paper highlights the results and findings of the studies and determines the gaps in the literature.

关键词： Cryptanalysis metaheuristic algorithms substitution cipher transposition cipher

Flexible impedance and capacitive tensile load sensor based on CNT composite

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Chinese Physics B 2016年第2期25卷 568-572页

作者： Zubair Ahmad kh S Karimov Farid Touati Department of Electrical Engineering College of Engineering Qatar University Doha 2713 Qatar Ghulam Ishaq khan Institute of Engineering Sciences and Technology Topi District Swabi KPK 23640 Pakistan Center for Innovative Development of Science and New Technologies Academy of Sciences Aini St. 299/2 Dushanbe 734063 Tajikistan

In this paper, the fabrication and investigation of flexible impedance and capacitive tensile load sensors based on carbon nanotube（CNT） composite are reported. On thin rubber substrates, CNTs are deposited from suspension in water and pressed at elevated temperature. It is found that the fabricated load cells are highly sensitive to the applied mechanical force with good repeatability. The increase in impedance of the cells is observed to be 2.0 times while the decrease in the capacitance is found to be 2.1 times as applied force increases up to 0.3 N. The average impedance and capacitive sensitivity of the cell are equal to 3.4 N^（-1） and 1.8 N^（-1）, respectively. Experimental results are compared with the simulated values,and they show that they are in reasonable agreement with each other.

关键词： carbon nanotubes flexible tensile load impedance capacitive

Hump nosed viper bite in Sri Lanka-descriptive observational study of 1543 cases

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Asian Pacific Journal of Tropical Medicine 2010年第11期3卷 902-905页

作者： Wijewantha HS Sellahewa kh National Hospital of Sri Lanka Colombo 10Sri Lanka

Objective:To identify the clinical manifestations of hump nosed viper envenomation and to recognize the available treatment methods to prevent ***:Descriptive observational study involving a series of 1 543 patients admitted with hump nosed viper bite to 5 major hospitals in Sri Lanka was *** collection was done consecutively during February 1990 and February *** Hypnale,identification of the biting snake was made by the corresponding author after visual examination of the dead or live snakes,which were brought to ***:Sixty seven(4.34%) patients developed systemic effects and two (0.1%) patients died due to effects of envenomation or complications of *** effects varied from coagulopathy,nephropathy to some neurological *** nine (3.8%) patients had only coagulopathy and they received either,intravenous isotonic saline to ensure adequate urine out put i.e.0.5 mL/kg /hour or 15 mL/kg of fresh frozen plasma(FFP). None of the patients that had coagulopathy developed renal *** of the sample by mildly venomous species of Hypnale may have contributed to the low incidence of systemic ***:It is likely that early hydration with normal saline or FFP can prevent acute renal *** showed a tendency for early correction of *** of FFP in hump nosed viper envenomation is worth studying in randomized double blind controlled clinical trials.

关键词： Snake bites Hump nosed viper Clinical manifestations Prevention of complications Fresh frozen plasma

The micropolar fluid model for blood flow through a tapered artery with a stenosis

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Acta Mechanica Sinica 2008年第6期24卷 637-644页

作者： kh.S.Mekheimer M.A.El Kot Department of Mathematics Faculty of ScienceAl-Azhar UniversityNasr CityCairo 11884Egypt Department of Mathematics Faculty of EducationSuez Canal UniversitySuezEgypt

A micropolar model for axisymmetric blood flow through an axially nonsymmetreic but radially symmetric mild stenosis tapered artery is presented. To estimate the effect of the stenosis shape, a suitable geometry has been considered such that the axial shape of the stenosis can be changed easily just by varying a parameter （referred to as the shape parameter）. The model is also used to study the effect of the taper angle Ф. Flow parameters such as the velocity, the resistance to flow （the resistance impedance）, the wall shear stress distribution in the stenotic region and its magnitude at the maximum height of the stenosis （stenosis throat） have been computed for different values of the shape parameter n, the taper angle Ф, the coupling number N and the micropolar parameter m. It is shown that the resistance to flow decreases with increasing the shape parameter n and the micropolar parameter m while it increases with increasing the coupling number N. So, the magnitude of the resistance impedance is higher for a micropolar fluid than that for a Newtonian fluid model. Finally, the velocity profile, the wall shear stress distribution in the stenotic region and its magnitude at the maximum height of the stenosis are discussed for different values of the parameters involved on the problem.

关键词： Micropolar fluid Blood flow Tapered artery

THE　STRUCTURAL　ELUCIDATION　AND　ABSOLUTE　CONFIGURATIONS　OF　TWO　NEW　POLYOXYGENATED　CYCLOHEXENES　FROM　UVARIA　GRANDIFLORA　ROXB．

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Chinese Chemical Letters 1996年第3期7卷 241-244页

作者： Pan, XP Yu, DQ Lee, kh BEIJING UNION MED COLL BEIJING 100050PEOPLES R CHINA UNIV N CAROLINA SCH PHARMNAT PROD LABDIV MED CHEM & NAT PRODCHAPEL HILLNC 27599 CHINESE ACAD MED SCI INST MAT MEDBEIJING 100050PEOPLES R CHINA

Two new polyoxygenated cyclohexenes,named uvarigranol E (I) andF(VII),were isolated from the rhizome of Uvaria grandiflora. On the basis ofspectral analysis and chemical derivatizations, including preparation of Mosheresters,the structures of I and VII were established as IR-acetoxymethyl-l,2Sdihydroxy-3 R,6S-dibenzoyloxy-cyclohex-4-ene and IR-hydroxymethyl-l,2Sdihydroxy-3R,6S-dibenzoyloxy cyclohex-4-ene.

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Pion parton distribution function in light-front holographic QCD

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Chinese Physics C 2020年第11期44卷 163-167页

作者： Lei Chang khépani Raya Xiaobin Wang School of Physics Nankai UniversityTianjin 300071China

The valence-quark distribution function of the pion has been of interest for decades;particularly,the profile it should adopt when x→1(the large-x behavior)has been the subject of a long-standing *** the light-front holographic QCD(LFHQCD)approach,this behavior is controlled by the so-called reparametrization function,wτ(x),which is not fully determined from first *** show that,owing to the flexibility of wτ(x),the large-x profile u^π(x)∼(1−x)^2 can be contained within the LFHQCD *** is in contrast to a previous LFHQCD study(Guy *** Teramond et al.,***.,120(18),2018)in which u^π(x)∼(1−x)^1 was found *** our observations,augmented by perturbative QCD and recent lattice QCD results,we state that the large-x exponent of“2”cannot be excluded.

关键词： pion parton distribution function QCD

Deuterium retention in chemically vapor deposited tungsten carbide coatings and hot-rolled tungsten exposed to low-energy deuterium plasma

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Tungsten 2022年第1期4卷 10-19页

作者： Vladimir kh.Alimov Joachim Roth Frumkin Institute of Physical Chemistry and Electrochemistry Russian Academy of SciencesMoscow 119071Russia Max-Planck-Institut fur Plasmaphysik 85748 GarchingGermany

Samples of chemically vapor deposited(CVD)coatings of tungsten carbides W_(45)C_(55)and W_(60)C_(40)and samples of hot-rolled tungsten were exposed to deuterium(D)plasma at sample temperatures ranging from 323 to 813 K,as a result of which the samples were irradiated with D ions with an energy of about 200 eV per D particle at a flux of D particles of about1.1×10^(21)D·m^(-2)·s^(-1)to a fluence of about 2×10^(24)D·m^(-2).The concentration of deuterium in these samples was examined by the D(3 He,p)4 He nuclear *** on the measured deuterium depth profiles and assuming that these profiles are determined by diffusing D atoms,the diffusion coefficients of deuterium in the CVD tungsten carbide coatings were *** these diffusion coefficients,an estimate of the Arrhenius relation for the diffusion coefficients of deuterium in CVD tungsten carbide coatings was obtained:D=2.5×10^(-3)exp(-1.12 eV/kT)m~2·s^(-1),where T is temperature expressed in Kelvin,and k is the Boltzmann *** concentration of trapped deuterium in the bulk of CVD tungsten carbide coatings is practically independent of the stoichiometry of the *** decreases from about 5×10^(-2)to about 7×10^(-4)D/(W+C)with an increase in the deuterium plasma exposure temperature from 373 to 813 *** concentration of trapped deuterium in hot-rolled tungsten,expressed in units of the D/W atomic ratio,is more than an order of magnitude lower than the concentration of deuterium in tungsten carbides,and also decreases with increasing plasma exposure temperature.

关键词： Chemically vapor deposited tungsten carbides Tungsten Deuterium plasma Deuterium depth profiles Deuterium diffusion coefficients

Performance Evaluation and Effectiveness of the Reverberation Room

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Sound & Vibration 2021年第1期55卷 43-55页

作者： Mohamed Abd-Elbasseer Hatem kh Mohamed Acoustics Laboratory National Institute of Standards(NIS)GizaEgypt

This research presents a thorough evaluation of the reverberation room at Acoustics Laboratory in National Institute of Standards(NIS)according to the related international *** evaluation aims at examining the room performance and exploring its effectiveness in the frequency range from 125 Hz to 10000 Hz according to the international standard *** room,which was designed and built several years ago,is an irregular rectangular shape free from *** volume is about 158.84 m^(3),which meets the requirement of the ISO 354 standard Lmax00 Hz respectively;however Schroder frequency is 400 *** of cut-off frequency and modal density showed adequate modes that give acceptable uniformity starting comfortably from frequency of 125 *** room has a reverberation time that is suitable for its size over the frequency range of *** room sound absorption surface area and its sound absorption coefficient satisfy the criteria given in ISO 3741 and ISO *** is an accepted diffuse sound field inside the room due to the standard deviation of measured sound level,which is less than 1.5 dB over all the frequency *** only exception was 125 Hz which may be due to a lack of diffusivity of the sound field at this *** evaluation proves that the NIS reverberation room is in full agreement with the international standards,which in turns qualifies the room to host measurements inside without concerns.

关键词： Reverberation room cut-off frequency sound absorption spatial uniformity modal counts

Synthesis of thiopyrano[4″,3″:4′,5′]pyrido[3′,2′:4,5]furo[3,2-d]pyrimidines

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Chinese Chemical Letters 2010年第6期21卷 669-673页

作者： Essam kh. Ahmed Mohamed A. Ameen Chemistry Department Faculty of ScienceEl Minia UniversityEl Minia 61519Egypt

Reactions of the 6-hydroxy-thiopyrano[3,4-c]pyridine-5-carbonitrile derivative 1 withα-halo-carbonyl compounds gave the ortho-substituted intermediates 2a-c which were converted into furo[2,3-b]thiopyrano[4,3-d]pyridines 3a-c by fusion of a furan moiety under basic *** cyclization of 3a-c led to a fusion of a pyrimidine ring,yielding the tetracyclic products 6,7 and *** addition,condensation of 6 with various aromatic aldehydes afforded the corresponding imines 9a,*** reaction of 7 gave products 10a,b.

关键词： S N-Heterocycles S N O-Heterocyles Furo[2 3-b]thiopyrano[4 3-d]pyridine Thiopyranopyridofuropyrimidines