Three parallel algorithms for classical molecular dynamics are presented. The first assigns each processor a fixed subset of atoms; the second assigns each a fixed subset of inter-atomic forces to compute; the third assigns each a fixed spatial region. The algorithms are suitable for molecular dynamics models which can be difficult to parallelize efficiently—those with short-range forces where the neighbors of each atom change rapidly. They can be implemented on any distributed-memory parallel machine which allows for message-passing of data between independently executing processors. The algorithms are tested on a standard Lennard-Jones benchmark problem for system sizes ranging from 500 to 100,000,000 atoms on several parallel supercomputers--the nCUBE 2, Intel iPSC/860 and Paragon, and Cray T3D. Comparing the results to the fastest reported vectorized Cray Y-MP and C90 algorithm shows that the current generation of parallel machines is competitive with conventional vector supercomputers even for small problems. For large problems, the spatial algorithm achieves parallel efficiencies of 90% and a 1840-node Intel Paragon performs up to 165 faster than a single Cray C9O processor. Trade-offs between the three algorithms and guidelines for adapting them to more complex molecular dynamics simulations are also discussed.

Fast parallel algorithms for short-range molecular dynamics

다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

Thank you for downloading using multivariate statistics. As you may know, people have look hundreds times for their favorite novels like this using multivariate statistics, but end up in infectious downloads. Rather than reading a good book with a cup of tea in the afternoon, instead they juggled with some harmful bugs inside their laptop. using multivariate statistics is available in our digital library an online access to it is set as public so you can download it instantly. Our books collection saves in multiple locations, allowing you to get the most less latency time to download any of our books like this one. Merely said, the using multivariate statistics is universally compatible with any devices to read.

Using Multivariate Statistics

Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

Phd by thesis

The tensile strengths of individual multiwalled carbon nanotubes (MWCNTs) were measured with a “nanostressing stage” located within a scanning electron microscope. The tensile-loading experiment was prepared and observed entirely within the microscope and was recorded on video. The MWCNTs broke in the outermost layer (“sword-in-sheath” failure), and the tensile strength of this layer ranged from 11 to 63 gigapascals for the set of 19 MWCNTs that were loaded. Analysis of the stress-strain curves for individual MWCNTs indicated that the Young's modulus E of the outermost layer varied from 270 to 950 gigapascals. Transmission electron microscopic examination of the broken nanotube fragments revealed a variety of structures, such as a nanotube ribbon, a wave pattern, and partial radial collapse.

https://science.sciencemag.org/content/sci/287/5453/637.full.pdf

Strength and breaking mechanism of multiwalled carbon nanotubes under tensile load

Dynamic behavior of silicon carbide

https://doi.org/10.1016/j.matt.2020.10.029 We thank Huskey, Westneat, and Grubich for the detailed account on the arapaima and piranha. Their article is not only informational but adds to our understanding of the complex relationship between evolution, environment, and predator-prey dynamics. We are by no means evolutionary biologists, but materials scientists, and the sole goal of our contributions has been to clearly demonstrate that the arapaima scales are a formidable biological structure with great toughness, among the highest among biological materials, with an impressive JIc fracture toughness of ~200 kJm . We unknowingly narrowed Currey’s conclusion about the protection offered by the arapaima scale to piranhas. He states: ‘‘The huge teleost freshwater fish Arapaima gigas, which can exceed 3 m in length, has somewhat similarly layered scales, which probably make it effectively immune to attack (Torres et al., 2008).’’ Torres et al. preceded us in the publication of the results and were the first to analyze the structure of the scale and to suggest their outstanding toughness. Thus, these scales are a superb defense against predators.

Offering Toughness and Protection, Arapaima Scales Provide Effective Defense against Predation

Erratum to “Heusler alloys: Past, properties, new alloys, and prospects” [Progress Mater. Sci. 132 (2023) 101017]

: This program supported the visit of Professor V. F. Nesterenko, Lavrentiev Institute of Hydrodynamics, Novosibirsk, Russia to UCSD, La Jolla, CA. Associated research focused on shock and shear-initiated chemical reactions and the use of the thick- walled cylinder method for the generation of high shears at high strain rates. The program was successfully completed with the firm establishment of collaborative research and opening of new research areas.

Marc A. Meyers

Papers

Dynamic behavior of silicon carbide

Offering Toughness and Protection, Arapaima Scales Provide Effective Defense against Predation

Erratum to “Heusler alloys: Past, properties, new alloys, and prospects” [Progress Mater. Sci. 132 (2023) 101017]

A Fundamental Investigation of Shock-Induced Reactions: The Role of Plastic Deformation and Synthesis of Ultra-Hard Materials

Jackfruit: Composition, structure, and progressive collapsibility in the largest fruit on the Earth for impact resistance.