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Job shop scheduling problem with alternative machines using genetic algorithms

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Journal of Central South University 2012年第5期19卷 1322-1333页

作者： i.A.Chaudhry National University of Sciences and Technology IslamabadPakistan

The classical job shop scheduling problem(JSP) is the most popular machine scheduling model in practice and is known as *** formulation of the JSP is based on the assumption that for each part type or job there is only one process plan that prescribes the sequence of operations and the machine on which each operation has to be ***,JSP with alternative machines for various operations is an extension of the classical JSP,which allows an operation to be processed by any machine from a given set of *** this problem requires an additional decision of machine allocation during scheduling,it is much more complex than *** present a domain independent genetic algorithm(GA) approach for the job shop scheduling problem with alternative *** GA is implemented in a spreadsheet *** performance of the proposed GA is analyzed by comparing with various problem instances taken from the *** result shows that the proposed GA is competitive with the existing approaches.A simplified approach that would be beneficial to both practitioners and researchers is presented for solving scheduling problems with alternative machines.

关键词： alternative machine genetic algorithm (GA) job shop, scheduling spreadsheet

Effect of the high-power electromagnetic pulses on the reactivity of the coal-water slurry in hot environment

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Chinese Journal of Chemical Engineering 2020年第12期28卷 3145-3151页

作者： M.V.Belonogov R.i.Taburchinov R.i.Egorov National Research Tomsk Polytechnic University TomskRussian Federation

An effect of the high-power electromagnetic pulses onto the droplet of coal-water slurry inside the furnace was *** contrary to the previously investigated laser-induced fuel atomization that occurs at the room temperature,the pre-heated(to 400 K)slurry becomes dry enough to prevent the explosion-like steam ***,fuel does not atomize and the ignition does not ***,the absorption of several laser pulses leads to evident sintering of irradiated surface with following increase of the ignition delay time for up to 24%.Variation of the pulse energy in range 48-118 mJ(corresponding intensity up to 2.4 J·cm^-2)leads to certain variation of the increase of ignition *** strong pulsed overheating of the coal water slurry which does not initiate the fine atomization of the fuel generally makes its ignition longer.

关键词： Waste-derived fuels Coal-water slurry Auto-ignition ignition delay time High-power laser pulse

Host-guest complexes of cucubit[8]uril with phenanthrolines and some methyl derivatives

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Science China Chemistry 2005年第4期48卷 305-314页

作者： DAY Anthony i Chemistry Discipline School of Physical Environmental and Mathematical SciencesUniversity College UNSWAustralian Defence Force AcademyCanberraACT2600 Australia

The host-guest relationship between cucurbit[8]uril,phenanthrolines and some methyl substituted 1,10-phenanthrolines has been investigated by using 1H NMR spectroscopy and fluorescence *** results showed that phenanthrolines as molecular guests bind in the cavity and portal of cucurbit[8]uril in a ratio of 2:1 (guest to host).The phenanthroline isomers 1,10-,1,7-and 4,7-showed red shifts between 47 and 108 nm and pronounced in-creases in fluorescent *** same isomers produced inclusion complexes with cucur-bit[8]uril which had moderate to fast exchange rates on the 1H NMR time *** methyl substituted 1,10-phenanthrolines studied gave stable inclusion complexes in a ratio of 2:1 which showed slow exchange *** guests formed p-p stacked pairs which were cavity bound but also partly protruded from only one portal forming unsymmetrical host-guest *** addition,these p-p stacked pairs formed orientation isomers within the confines of the cucur-bit[8]uril cavity.

关键词： 1H NMR technique, fluorescence, cucurbituril, phenanthroline, host-guest, orientation isomers.

Characterization of Arithmetic Functions that Preserve the Sum-of-squares Operation

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Acta Mathematica Sinica,English Series 2014年第4期30卷 689-695页

作者： Bojan BAi Department of Mathematics and informatics University of Novi Sad

We characterize all functions f ： N → C such that f（m^2 ＋ n^2） = f（m）^2 ＋ f（n）^2 for all m, n ∈ N. it turns out that all such functions can be grouped into three families, namely f ≡ 0, f（n） = ±n （subject to some restrictions on when the choice of the sign is possible） and f（n） =±l/2（again subject to some restrictions on when the choice of the sign is possible）.

关键词： Arithmetic function functional equation sum of squares

A precise monitoring of snow surface height in the region of Lambert Glacier basin-Amery ice Shelf,East Antarctica

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Science China Earth Sciences 2005年第1期48卷 100-111页

作者： i.Allison Australian Antarctic Division and Antarctic Climate and Ecosystems CRC

The net surface snow accumulation on the Antarctic ice sheet is determined by a combination of precipitation, sublimation and wind redistribution. We present a one-year record of hourly snow-height measurements at LGB69 (70°50'S, 77°04'E, 1850 m a.s.l.). east side of Lambert Glacier basin (LGB), and 4 year record at G3 (70°53'S, 69°52'E, 84 m a.s.l.), Amery ice Shelf (AiS). The measurements were made with ultrasonic sensors mounted on automatic weather stations installed at two sites. The snow accumulation at LGB69 is approximately 70 cm. Throughout the winter, between April and September, there was little change in surface snow height (SSH) at the two sites. The negative SSH change is due to densification at LGB69, and is due to both ablation and densification at G3. The strongest accumulation at two sites occurred during the period between October and March (accounting for 101.6% at LGB69), with four episodic increasing events occurring during 2002 for LGB69, and eight events during 1999-2002 for G3 (2 to 3 events per year). At LGB69, these episodic events coincided with obvious humidity 'pulses' and decreases of incoming solar radiation as recorded by the AWS. Observations of the total cloud amount at Davis station, 160 km NNE of LGB69, showed good correlation with major accumulation events recorded at LGB69. There was an obvious anti-correlation between the lowest cloud height at Davis and the daily accumulation rate at LGB69. Although there was no correlation over the total year between wind speed and accumulation at LGB69, large individual accumulation events are associated with episodes of strong wind (>7 m/s), we estimate drift snow may contribute to total SSH up to 35%. Strong accumulation events at LGB69 are associated with major storms in the region and inland transport of moist air masses from the coast.

关键词： Antarctica, Lambert Glacier basin, Amery ice Shelf, accumulation, katabatic wind.

Single and multi domain buckled germanene phases on Al(111)surface

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Nano Research 2019年第12期12卷 2988-2996页

作者： Dmitriy A.Muzychenko Sergey i.Oreshkin Vladimir i.Panov Chris Van Haesendonck Andrey i.Oreshkin Faculty of Physics Lomonosov Moscow State University119991 MoscowRussia Sternberg Astronomical institute Lomonosov Moscow State University119234 MoscowRussia Solid-State Physics and Magnetism Section KU LeuvenBE-3001 LeuvenBelgium

The simultaneous formati on of single domain(3×3)and multi domai n(√7×√7)R(±19.1°)germa nene phases on Al(111)surface in thesub-monolayer range was studied using seanning tunneling microscopy(STM)and density functional theory(DFT)based *** results revealed that both germa nene phases nu cleate and grow in dependently from each other and regardless of Al substratetemperature within significantly expanded range Ts=27-200℃.Our results unambiguously showed that STM images with hexagonalcontrast yield correct-resolved structure for both germanene phases,while honeycomb contrast is a result of an artificial tip-induced STM ***-principles calculations suggested atomic models with strongly buckled germanene(2×2)/Al(111)(3×3)and(√3×√3)R30°/Al(111)(√7×√7)R(±19.1°)with one of eight and one of six Ge atoms protruding upward respectively,that consistently describe the experimentally observed STM images both for single and multi domai n surface *** to the DFT based simulati ons both germa nene(2×2)and(√3×√3)R30°superstructures have a stretched lattice strain with respect to the ideal free-standing germa nene by 6.2%and 13.9%,***,numerous small domains separated by domain boundaries in the(√3×√3)R30°/Al(111)(√7×√7)R(±19.1°)germanenephase tend to reduce the surface energy and prevent the formation of extended single domains,in contrast to the(2×2)/Al(111)(3×3)***,our experimental results showed that the nucleation and growth of germa nene on Al(111)surface yield strong modifications of Alsurface even at room temperature(RT),which may be contributed to the formation of Al-Ge alloy due to Ge surface solid-states reactivitythat was ignored in recent *** is already evident from our present findings that the role of Al atoms in the formation of(3×3)and(√7×√7)R(±19.1°)germa nene phases is worthy to be carefully studied in the future,which could be an important knowledge for large-quantityfabrication of germane

关键词： germanene two-dimensional(2D)materials scanning tunneling microscopy density functional theory aluminum

On Evaluation of Overlap integrals with Noninteger Principal Quantum Numbers

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Communications in Theoretical Physics 2004年第5X期42卷 753-756页

作者： i.i.Guseinov B.A.Mamedov DepartmentofPhysics FacultyofArtsandSciencesOnsekizMartUniversityCanakkaleTurkey DepartmentofPhysics FacultyofArtsandSciencesGaziosmanpasaUniversityTokatTurkey

By use of complete orthonormal sets of ψα exponential-type orbitals (ψα-ETOs, α = 1, 0,-1,-2, ...) the series expansion formulas for the noninteger n* Slater-type orbitals (NiSTOs) in terms of integer n Slater-type orbitals(iSTOs) are derived. These formulas enable us to express the overlap integrals with NiSTOs through the overlap integrals over iSTOs with the same and different screening constants. By calculating concrete cases the convergence of the series for arbitrary values of noninteger principal quantum numbers and screening constants of NiSTOs and internuclear distances is tested. The accuracy of the results is quite high for quantum numbers, screening constants and location of STOs.

关键词：指数轨道游标量子数迭代积分 NiSTOS 原子核

Simulation of detection and scattering of sound waves by the lateral line of a fish

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Chinese Physics B 2022年第2期31卷 398-404页

作者： V M Adamyan i Y Popov i V Blinova V V Zavalniuk Odessa i.i.Mechnikov National University Dvoryanskaya Str.2Odesa65082Ukraine iTMO University Kronverkskiy49Saint Petersburg197101Russia Odessa Military Academy 10 Fontanska RoadOdesa 65009Ukraine

A solvable model of lateral line of a fish based on a wave equation with additional boundary conditions on a set of isolated points is *** the framework of this model it is shown that the ratio of pressures on lateral lines on different fish flanks,as well as the cross section of sound scattering on both the lines,strongly depends on angles of incidence of incoming sound *** strong angular dependence of the pressure ratio seems to be sufficient for the fish to determine the directions from which the sound is coming.

关键词： acoustic equation point self-adjoint perturbations of Laplace operator scattering lateral line

Knowledge Attitude and Practice about Water-Pipe Smoking among Saudi Population

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Journal of Biosciences and Medicines 2020年第3期8卷 58-72页

作者： Reema Fahad Abdulrahman Alnumair Amal Hussain Mohammed Ali hussam Ahmed Mohammed Alghamdi Department of Medical Laboratories College of Applied Medical Sciences Qassim University Qassim Kingdom of Saudi Arabia

Water pipe smoking has been practiced extensively for about 400 years. Water pipe smoking is common in the Saudi Arabia. Water-pipe smoking exposes smokers to high levels of tobacco and toxins. An observational and cross-sectional survey carried among 1170 participants to determine the knowledge, attitude, and practice about water-pipe smoking among Saudi population. Data was collected and obtained by the online questionnaire that has been created in Google form and then published in different social media platforms over a period from September 2019 to November 2019. The data were entered in Excel and analyzed in Epiinfo7 statistical software to get descriptive statistics. Results: About 70% were females and 30% male, 43% of them are university students with 83% in the age group of the 18 - 25 high participants. Low knowledge of Carbon monoxide poisoning effects = 78%, While 54% of the participants showed low knowledge about infectious disease transmitted by water-pipe. The Knowledge about water pipe contents and carbon monoxide poisoning was low. Further efforts will be necessary to increase the level of awareness among participants in Saudi Arabia regarding water pipe contents and carbon monoxide poisoning.

关键词： Knowledge Attitude Practice Water-Pipe Smoking Saudi