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

抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

Single-layer metal dichalcogenides are two-dimensional semiconductors that present strong potential for electronic and sensing applications complementary to that of graphene.

/pdf/electronics-and-optoelectronics-of-two-dimensional-2jbqr1unvw.pdf

Electronics and optoelectronics of two-dimensional transition metal dichalcogenides.

[신간의 별자리x] 우리/미술, 그리고 ‘슬픔의 박물관’

Unsupervised image morphing is a very challenging task in machine learning, whereas it is relatively easy and common for the human brain. Even a simple deformation of an object such as a translation or scaling operation follows a complex curved trace in a high-dimensional image space. The learning of such a complex curved manifold needs human assistance or sufficiently dense intermediate data points. Presented is a novel transformation framework with which a curved manifold describing the deformation of images turns into a simple linear structure in the transformed space. Therefore, image morphing can be achieved by simple linear superposition using the conjugate image representation.

Unsupervised morphing by conjugate image processing

The effect of block lengths on micelle structure in blends of styrene–isoprene diblock copolymer and poly(vinyl methyl ether)

Biomimetic Metal–Organic Framework-Derived Porous Carbon Welded Carbon Nanotube Networks for Strain Sensors with High Sensitivity and Wide Sensing Range

Observation of the Initial Stage of 3C-SiC Heteroepitaxial Growth on the Si Nanomembrane

We report mode-locking of an optically pumped VECSEL using a graphene-based saturable absorber mirror (GSAM). Self-starting and stable modelocked operation is demonstrated with 473 fs pulses at 1.5 GHz repetition rate and 949 nm center wavelength. Wavelength tuning is achieved over a 46 nm bandwidth. We discuss the mirror design, the fabrication of the GSAMs, and give an outlook on further optimization of the design, including dielectric top coatings to protect the graphene and to increase the flexibility in the design.

/pdf/graphene-saturable-absorbers-for-vecsels-24l9x4qib7.pdf

Jong Hyun Ahn

Papers

Unsupervised morphing by conjugate image processing

The effect of block lengths on micelle structure in blends of styrene–isoprene diblock copolymer and poly(vinyl methyl ether)

Biomimetic Metal–Organic Framework-Derived Porous Carbon Welded Carbon Nanotube Networks for Strain Sensors with High Sensitivity and Wide Sensing Range

Observation of the Initial Stage of 3C-SiC Heteroepitaxial Growth on the Si Nanomembrane

Graphene saturable absorbers for VECSELs