325 research outputs found
Prevention of Catastrophic Volcanic Eruptions
Giant volcanic eruptions emit sulphate aerosols as well as volcanic ash. Needless to say that volcanic ash causes significant damage to the environment and human at large. However, the aerosols are even worse. They reach the Stratosphere and stay there for months to years reflecting insolation. As a result, air temperature at the Earth's surfaces drops. Even a slight temperature drop may cause severe food shortage. Yellowstone supervolcano, for example, can even make human in the Northern Hemisphere extinct in several hundred thousand years. Therefore, gradual energy release by supercritical geothermal power generation was proposed to prevent such catastrophic eruptions. The necessary technical innovation is drilling into the depth. However, after the innovation, the power generation itself would be profitable. The risk is unpredicted induction of unwanted catastrophic eruptions.ISERME 2017:International Symposium on Earth Resources Management & Environment. 29-30 August 2017, Colombo, Sri Lank
Impact on permeability due to axial stress disturbances for cretaceous sandy shale
Seismic waves generated from earthquakes and artificial surface vibration might alter the water level in the wells and oil or gas production. These transient stress disturbances prospectively caused the permeability change due to new pathway occurring or existing pathway being cleared. The permeability change might encourage enhancing gas recovery, inducing small earthquakes preventing future large earthquakes, and de-routing underground water flow for various purposes. The prospective permeability increase by axial stress disturbances of Cretaceous sandy shale may effectively expand the capacity of methane gas recovery of Kushiro Coal Mine. The paper observes the permeability change of intact or triaxially fractured Kushiro Cretaceous sandy shale by axial stress disturbances. It will be shown that increasing and decreasing factors might work together on permeability.MMIJ Fall Meeting 2017, Sept. 26-28 2017, Sapporo, Japan (資源・素材2017(札幌): 平成29年度資源・素材関係学協会合同秋季大会, 2017年9月26日~28日, 北海道大学, 札幌市
Redshift Dependent Lag-Luminosity Relation in 565 BASTE Gamma Ray Bursts
We compared redshifts from Yonetoku relation and from the
lag-luminosity relation for 565 BASTE GRBs and were surprised to find that the
correlation is very low. Assuming that the luminosity is a function of both
and the intrinsic spectral lag , we found a new redshift
dependent lag-luminosity relation as with the correlation coefficient of 0.77
and the chance probability of . To check the validity of
this method, we examined the other luminosity indicator, Amati relation, using
and the observed fluence and found the correlation coefficient of 0.92
and the chance probability of . Although the spectral lag
is computed from two channels of BATSE, our new lag-luminosity relation
suggests that a possible lag-luminosity relation in the \swift era should also
depend on redshift
Are Red Tidal Features Unequivocal Signatures of Major Dry Mergers?
We use a cosmological numerical simulation to study the tidal features
produced by a minor merger with an elliptical galaxy. We find that the
simulated tidal features are quantitatively similar to the red tidal features,
i.e., dry tidal features, recently found in deep images of elliptical galaxies
at intermediate redshifts. The minor merger in our simulation does not trigger
star formation due to active galactic nuclei heating. Therefore, both the tidal
features and the host galaxy are red, i.e. a dry minor merger. The stellar mass
of the infalling satellite galaxy is about 10^10 Msun, and the tidal debris
reach the surface brightness of mu_R~27 mag arcsec^-2. Thus, we conclude that
tidal debris from minor mergers can explain the observed dry tidal features in
ellipticals at intermediate redshifts, although other mechanisms (such as major
dry mergers) may also be important.Comment: 7 pages, 7 figures, accepted for publication in Ap
Constraints on and of Dark Energy from High Redshift Gamma Ray Bursts
We extend the Hubble diagram up to using 63 gamma-ray bursts (GRBs)
via peak energy-peak luminosity relation (so called Yonetoku relation), and
obtain constraints on cosmological parameters including dynamical dark energy
parametrized by . It is found that
the current GRB data are consistent with the concordance model, (), within two sigma level.
Although constraints from GRBs themselves are not so strong, they can improve
the conventional constraints from SNeIa because GRBs have much higher
redshifts. Further we estimate the constraints on the dark-energy parameters
expected by future observations with GLAST (Gamma-ray Large Area Space
Telescope) and \swift by Monte-Carlo simulation. Constraints would improve
substantially with another 150 GRBs.Comment: 5 pages, 6 figures. Submitted tu MNRA
Effects of Intermittent Breath Holding during Prolonged Exercise on Ventilation and Blood Lactate Responses
Galactic Wind Signatures around High Redshift Galaxies
We carry out cosmological chemodynamical simulations with different strengths
of supernova (SN) feedback and study how galactic winds from star-forming
galaxies affect the features of hydrogen (HI) and metal (CIV and OVI)
absorption systems in the intergalactic medium at high redshift. We find that
the outflows tend to escape to low density regions, and hardly affect the dense
filaments visible in HI absorption. As a result, the strength of HI absorption
near galaxies is not reduced by galactic winds, but even slightly increases. We
also find that a lack of HI absorption for lines of sight (LOS) close to
galaxies, as found by Adelberger et al., can be created by hot gas around the
galaxies induced by accretion shock heating. In contrast to HI, metal
absorption systems are sensitive to the presence of winds. The models without
feedback can produce the strong CIV and OVI absorption lines in LOS within 50
kpc from galaxies, while strong SN feedback is capable of creating strong CIV
and OVI lines out to about twice that distance. We also analyze the mean
transmissivity of HI, CIV, and OVI within 1 h Mpc from star-forming
galaxies. The probability distribution of the transmissivity of HI is
independent of the strength of SN feedback, but strong feedback produces LOS
with lower transmissivity of metal lines. Additionally, strong feedback can
produce strong OVI lines even in cases where HI absorption is weak. We conclude
that OVI is probably the best tracer for galactic winds at high redshift.Comment: 16 pages, 16 figures, ApJ in press. Higher resolution version
available at http://www.ociw.edu/~dkawata/research/papers.htm
SimplyRetrieve: A Private and Lightweight Retrieval-Centric Generative AI Tool
Large Language Model (LLM) based Generative AI systems have seen significant
progress in recent years. Integrating a knowledge retrieval architecture allows
for seamless integration of private data into publicly available Generative AI
systems using pre-trained LLM without requiring additional model fine-tuning.
Moreover, Retrieval-Centric Generation (RCG) approach, a promising future
research direction that explicitly separates roles of LLMs and retrievers in
context interpretation and knowledge memorization, potentially leads to more
efficient implementation. SimplyRetrieve is an open-source tool with the goal
of providing a localized, lightweight, and user-friendly interface to these
sophisticated advancements to the machine learning community. SimplyRetrieve
features a GUI and API based RCG platform, assisted by a Private Knowledge Base
Constructor and a Retrieval Tuning Module. By leveraging these capabilities,
users can explore the potential of RCG for improving generative AI performance
while maintaining privacy standards. The tool is available at
https://github.com/RCGAI/SimplyRetrieve with an MIT license.Comment: 12 pages, 6 figure
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