1,252 research outputs found
Characteristics of Human and Mouse Orthologous Protein-Coding Nucleotide Sequences with Large G+C Content Variations
Characteristics of human and mouse orthologous gene sequences which have large G+C content variations were investigated in this study. The orthologous gene pairs were classified into two groups according to the deviation between human and mouse G+C content at the third codon position (GC3) and were subsequently analyzed. In one group, mouse genes had higher GC3 than the corresponding human genes and in another group, human genes had higher GC3 than mouse. Furthermore, the orthologous pairs were separated based on the deviation between human or mouse GC3 and the G+C content at the third codon position of identical codons (IC3), to examine the effect of increased or decreased G+C content in human or mouse sequences. The nucleotide substitution patterns between human and mouse sequences in the two groups were remarkably distinct, and consistent with the state of G+C-rich or G+C-poor sequences. The effect of increase or decrease of G+C content in human or mouse sequences was not clear in the nucleotide substitution patterns. The chromosomal locations of human and mouse orthologous gene pairs were different between the two groups. The genes located on an identical syntenic segment showed the trend of having similar G+C content. Moreover, the same gene order of some genes on different chromosomes of both species demonstrated the gene rearrangements between human and mouse. Our study indicated that the chromosomal locations and rearrangements are associated with the GC3 variation between human and mouse sequences
A Serial Domain Decomposition Method for Discrete Element Method Simulation of Soil–Wheel Interactions
We applied a serial domain decomposition method (DDM) to our two-dimensional discrete element method (DEM) program and investigated the effectiveness of DDM in terms of computer hardware. The developed program could obtain sufficiently accurate results for wheel slip, traction, and gross traction, comparable to DEM without serial DDM. We also confirmed that the soil deformation field under the wheel for DEM with serial DDM was similar to that for DEM without DDM. Moreover, the increased sub-domain loop was effective in reducing computational time in the case of serial DDM. Since each sub-domain loop contains the time integration and coordinate update routine, further optimization of memory usage in our serial DDM may be possible, which would allow large-scale three-dimensional DEM analysis on an economical desktop PC system
siEDM: an efficient string index and search algorithm for edit distance with moves
Although several self-indexes for highly repetitive text collections exist,
developing an index and search algorithm with editing operations remains a
challenge. Edit distance with moves (EDM) is a string-to-string distance
measure that includes substring moves in addition to ordinal editing operations
to turn one string into another. Although the problem of computing EDM is
intractable, it has a wide range of potential applications, especially in
approximate string retrieval. Despite the importance of computing EDM, there
has been no efficient method for indexing and searching large text collections
based on the EDM measure. We propose the first algorithm, named string index
for edit distance with moves (siEDM), for indexing and searching strings with
EDM. The siEDM algorithm builds an index structure by leveraging the idea
behind the edit sensitive parsing (ESP), an efficient algorithm enabling
approximately computing EDM with guarantees of upper and lower bounds for the
exact EDM. siEDM efficiently prunes the space for searching query strings by
the proposed method, which enables fast query searches with the same guarantee
as ESP. We experimentally tested the ability of siEDM to index and search
strings on benchmark datasets, and we showed siEDM's efficiency.Comment: 23 page
ショウワキチ キショウ カンソクチ ノ トウケイ テキ チョウサ
1957年3月から1958年2月までの昭和基地の風向,風速,気温について,毎時の観測値を整理した結果を報告する.(1)風向 最多風向は3, 4,5の各月はNEで,その他の月はNNE,南よりの風(SE-SW)は4,5,9,12,2の各月に多く,静穏は7,8,9の3ヶ月に多い.1年を通じては,全観測回数の約60%はNNE-ENEの風である.(2)風速 風力9以上(20.8m/s以上)は3,7,8の各月に多く,それぞれの月の約6%風力3以下(3.4m/s以下)は8,9,10,12,2の各月に多く,それぞれの月の60%を越す.風速の日変化は,10月から2月までは規則的で,最大は5時前後,最小は20時前後である.(3)気温 1年を通じ,0℃以上は全観測回数の8%,-30℃以下は1%で,0.0-9.9℃が45%を占める.旬平均値によると,低温と弱風速および南よりの風がよく対応している
The spatiokinematical structure of H_2O and OH masers in the "water fountain" source IRAS 18460-0151
Using the Very Long Baseline Array and the European VLBI Network, we have
observed 22.2 GHz H_2O and 1612 MHz OH masers in the "water fountain" source
IRAS 18460-0151. The H_2O maser spectrum has a very wide line-of-sight velocity
range (~310 km/s) and consists of three groups of emission features at the
blue-shifted (-68 km/s <~ V_LSR <~ -17 km/s) and red-shifted (V_LSR ~= 240
km/s) edges as well as around the systemic velocity (112 km/s <~ V_LSR <~ 133
km/s). The first two H_2O spectral components exhibit a highly-collimated
high-velocity bipolar jet on the sky, with an angular separation of ~120
milliarcseconds (mas) (240 AU in linear length) and a three-dimensional flow
velocity of ~160 km/s. The flow dynamical age is estimated to be only ~6 yr (at
the time of the observation epochs of 2006--2007). Interestingly, the systemic
velocity component clearly exhibits a spherically-expanding outflow with a
radius of ~36 AU and a flow velocity of ~9 km/s. On the other hand, the OH
maser spectrum shows double peaks with a velocity separation of ~25 km/s
(V_LSR=$111--116 and 138--141 km/s), as typically seen in circumstellar
envelopes of OH/IR stars. The angular offset between the velocity-integrated
brightness peaks of the two high-velocity H_2O components is ~25 mas (50 AU).
The offset direction and the alignment of the red-shifted maser spots are
roughly perpendicular to the axis of the H_2O maser flow. High-accuracy
astrometry for the H_2O and OH masers demonstrates that the collimated fast jet
and the slowly expanding outflow originate from a single or multiple sources
which are located within 15 mas (30 AU). On the other hand, the estimated
systemic velocity of the collimated jet (V_sys ~87--113 km/s) has a large
uncertainty. This makes it difficult to provide strong constraints on models of
the central stellar system of IRAS 18460-0151.Comment: 25 pages, 5 figures, 8 tables, accepted for publication in Ap
Do Water Fountain Jets Really Indicate the Onset of the Morphological Metamorphosis of Circumstellar Envelopes?
The small-scale bipolar jets having short dynamical ages from "water fountain
(WF)" sources are regarded as an indication of the onset of circumstellar
envelope morphological metamorphosis of intermediate-mass stars. Such process
usually happens at the end of the asymptotic giant branch (AGB) phase. However,
recent studies found that WFs could be AGB stars or even early planetary
nebulae. This fact prompted the idea that WFs may not necessarily be objects at
the beginning of the morphological transition process. In the present work, we
show that WFs could have different envelope morphologies by studying their
spectral energy distribution profiles. Some WFs have spherical envelopes that
resembles usual AGB stars, while others have aspherical envelopes which are
more common to post-AGB stars. The results imply that WFs may not represent the
earliest stage of the morphological metamorphosis. We further argue that the
dynamical age of a WF jet, which can be calculated from maser proper motions,
may not be the real age of the jet. The dynamical age cannot be used to justify
the moment when the envelope begins to become aspherical, nor to tell the
concrete evolutionary status of the object. A WF jet could be the innermost
part of a larger well-developed jet, which is not necessarily a young jet.Comment: 21 pages, 4 figures, accepted for publication in MNRA
High Velocity Precessing Jets from the Water Fountain IRAS 18286-0959 Revealed by VLBA Observations
We report the results of multi-epoch VLBA observations of the 22.2GHz water
maser emission associated with the "water fountain" IRAS 18286-0959. We suggest
that this object is the second example of a highly collimated bipolar
precessing outflow traced by water maser emission, the other is W43A. The
detected water emission peaks are distributed over a velocity range from
-50km/s to 150km/s. The spatial distribution of over 70% of the identified
maser features is found to be highly collimated along a spiral jet (jet 1)
extended southeast to northwest, the remaining features appear to trace another
spiral jet (jet 2) with a different orientation. The two jets form a
"double-helix" pattern which lies across ~200 milliarcseconds. The maser
distribution is reasonably fit by a model consisting of two bipolar precessing
jets. The 3D velocities of jet 1 and jet 2 are derived to be 138km/s and
99km/s, respectively. The precession period of jet 1 is about 56 years. For jet
2, three possible models are tested and they give different values for the
kinematic parameters. We propose that the appearance of two jets is the result
of a single driving source with significant proper motion.Comment: 84 pages, 16 figures, accepted for publication in Ap
Energy Aware Scheduler of Single/Multi-Node Jobs Considering CPU Node Heterogeneity
2022 IEEE 13th International Green and Sustainable Computing Conference (IGSC), 24-25 October 2022, Pittsburgh, PA, USAModern CPUs suffer from power efficiency heterogeneity, which can result in additional energy cost or performance loss. On the other hand, future supercomputers are expected to be power constrained. This paper focuses on energy aware scheduling algorithms targeted on two situations considering this node heterogeneity. In single-node situation, workload consists of various single-node jobs, Combinatorial Optimization Algorithm saves energy by calculating a local optimal power efficiency node allocation plan from KM (Kuhn-Munkres) algorithm. In multi-node situation, power cap causes load unbalancing in multi-node jobs due to the node heterogeneity. Sliding Window Algorithm targets on reducing such unbalancing by sliding window. Proposed algorithms are evaluated in the simulation and real supercomputer environment. In single-node situation, Combinatorial Optimization Algorithm achieved up to 2.92% saving. For the multi-node situation, workload is designed based on real historic workload, and up to 5.36% saving was achieved by Sliding Window Algorithm
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