108 research outputs found
Influence of Environment on Ageing Behaviour of the Polyurethane Film
In this work, UV-Vis spectra, FT-IR spectra, colour difference, yellowness index, and SEM micrographs were used to study the accelerated ageing behaviour of polyurethane films that exposed to UV radiation, O3 atmosphere, and UV/O3 integrated environment. During 200 hours of exposure in three different environment, the UV absorbance, the colour difference, the yellowness, and the absorption of âNH/âOH and âC=O bands in FT-IR spectra of the films increase gradually with increasing exposure time, respectively, and the films exposed to the three environments have different colour difference, yellowness index, UV-Vis spectra, and FT-IR spectra. The films are vulnerable to degradation and yellowing in the following environment order: O3 < UV < UV/O3. After exposure to UV radiation or O3 atmosphere, some degradation products and blisters are formed on the film surface. After exposure to UV/O3 integrated environment, there are strip blisters and micro-cracks on the film surface, and exists an obvious synergism between UV radiation and O3 atmosphere in accelerating the ageing of the polyurethane films
InstructSeq: Unifying Vision Tasks with Instruction-conditioned Multi-modal Sequence Generation
Empowering models to dynamically accomplish tasks specified through natural
language instructions represents a promising path toward more capable and
general artificial intelligence. In this work, we introduce InstructSeq, an
instruction-conditioned multi-modal modeling framework that unifies diverse
vision tasks through flexible natural language control and handling of both
visual and textual data. InstructSeq employs a multimodal transformer
architecture encompassing visual, language, and sequential modeling. We utilize
a visual encoder to extract image features and a text encoder to encode
instructions. An autoregressive transformer fuses the representations and
generates sequential task outputs. By training with LLM-generated natural
language instructions, InstructSeq acquires a strong comprehension of free-form
instructions for specifying visual tasks. This provides an intuitive interface
for directing capabilities using flexible natural instructions. Without any
task-specific tuning, InstructSeq achieves compelling performance on semantic
segmentation, referring expression segmentation/comprehension, and image
captioning. The flexible control and multi-task unification empower the model
with more human-like versatility and generalizability for computer vision. The
code will be released soon at https://github.com/rongyaofang/InstructSeq.Comment: 10 page
Back to the Starting Point: on the Simulation of Initial Magnetic Fields and Spin Periods of Non-accretion Pulsars
Neutron stars (NSs) play essential roles in modern astrophysics. Magnetic
fields and spin periods of newborn (zero age) NSs have large impact on the
further evolution of NSs, which are however poorly explored in observation due
to the difficulty of finding newborn NSs. In this work, we aim to infer the
magnetic fields and spin periods (Bi and Pi) of zero-age NSs from the observed
properties of NS population. We select non-accretion NSs (NANSs) whose
evolution is solely determined by magnetic dipole radiation. We find that both
Bi and Pi can be described by log-normal distribution and the fitting
sensitively depends on our parameters.Comment: 8 pages, 5 figures, accepted for publication in Ap
Ghost in the Minecraft: Generally Capable Agents for Open-World Enviroments via Large Language Models with Text-based Knowledge and Memory
The captivating realm of Minecraft has attracted substantial research
interest in recent years, serving as a rich platform for developing intelligent
agents capable of functioning in open-world environments. However, the current
research landscape predominantly focuses on specific objectives, such as the
popular "ObtainDiamond" task, and has not yet shown effective generalization to
a broader spectrum of tasks. Furthermore, the current leading success rate for
the "ObtainDiamond" task stands at around 20%, highlighting the limitations of
Reinforcement Learning (RL) based controllers used in existing methods. To
tackle these challenges, we introduce Ghost in the Minecraft (GITM), a novel
framework integrates Large Language Models (LLMs) with text-based knowledge and
memory, aiming to create Generally Capable Agents (GCAs) in Minecraft. These
agents, equipped with the logic and common sense capabilities of LLMs, can
skillfully navigate complex, sparse-reward environments with text-based
interactions. We develop a set of structured actions and leverage LLMs to
generate action plans for the agents to execute. The resulting LLM-based agent
markedly surpasses previous methods, achieving a remarkable improvement of
+47.5% in success rate on the "ObtainDiamond" task, demonstrating superior
robustness compared to traditional RL-based controllers. Notably, our agent is
the first to procure all items in the Minecraft Overworld technology tree,
demonstrating its extensive capabilities. GITM does not need any GPU for
training, but a single CPU node with 32 CPU cores is enough. This research
shows the potential of LLMs in developing capable agents for handling
long-horizon, complex tasks and adapting to uncertainties in open-world
environments. See the project website at https://github.com/OpenGVLab/GITM
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Beneficial Effect of Young Oocytes for Rabbit Somatic Cell Nuclear Transfer
Abstract This study was designed to examine the effect of the age of rabbit oocytes on the developmental potential of cloned embryos. The metaphase II oocytes used for nuclear transfer (NT) were collected at 10, 12, 14, and 16h post-hCG injection (hpi). The total number of oocytes collected per donor (21.4-23.7) at 12 to 16 hpi was similar, but significantly higher than that collected at 10 hpi (16.2). Additionally, a significant improvement in blastocyst development was achieved with embryos generated by electrically mediated cell fusion (56.0%), compared to those from nuclear injection (13.1 %) (Experiment 1). Markedly higher blastocyst development (45.8-54.5%) was also achieved with oocytes collected at 10-12 hpi than from those collected 14-16 hpi (8.3-14.3%) (Experiment 2). In Experiment 3, the blastocyst rates of NT embryos derived from oocytes harvested 12 hpi (39.2-42.8 %) were significantly higher than from those collected at 16 hpi (6.8-8.4 %) (p<0.05), regardless of the donor cell age. Kinase activity assays showed variable changes of activity in rabbit oocytes over the period of 10-16 hpi; however, there was no correlation with preimplantational development (blastocyst rate vs. MPF, R=0.326; blastocyst rate vs. MAPK, R=0.131). Embryo transfer of NT embryos utilizing 12 hpi oocytes resulted in one full-term but stillborn, and one live cloned rabbit; thus, an efficiency of 1.7 % (n=117) (Experiment 4). These results demonstrated that NT utilizing relatively young rabbit oocytes, harvested at 10-12h after hCG injection, was beneficial for the development of NT embryos.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/78139/1/clo.2008.0042.pd
Mask TextSpotter: An End-to-End Trainable Neural Network for Spotting Text with Arbitrary Shapes
Recently, models based on deep neural networks have dominated the fields of
scene text detection and recognition. In this paper, we investigate the problem
of scene text spotting, which aims at simultaneous text detection and
recognition in natural images. An end-to-end trainable neural network model for
scene text spotting is proposed. The proposed model, named as Mask TextSpotter,
is inspired by the newly published work Mask R-CNN. Different from previous
methods that also accomplish text spotting with end-to-end trainable deep
neural networks, Mask TextSpotter takes advantage of simple and smooth
end-to-end learning procedure, in which precise text detection and recognition
are acquired via semantic segmentation. Moreover, it is superior to previous
methods in handling text instances of irregular shapes, for example, curved
text. Experiments on ICDAR2013, ICDAR2015 and Total-Text demonstrate that the
proposed method achieves state-of-the-art results in both scene text detection
and end-to-end text recognition tasks.Comment: To appear in ECCV 201
Challenges in the Technology Development for Additive Manufacturing in Space
Instead of foreseeing and preparing for all possible scenarios of machine failures, accidents, and other challenges arising in space missions, it appears logical to take advantage of the flexibility of additive manufacturing for âin-space manufacturingâ (ISM). Manned missions into space rely on complicated equipment, and their safe operation is a great challenge. Bearing in mind the absolute distance for manned missions to the Moon and Mars, the supply of spare parts for the repair and replacement of lost equipment via shipment from Earth would require too much time. With the high flexibility in design and the ability to manufacture ready-to-use components directly from a computer-aided model, additive manufacturing technologies appear to be extremely attractive in this context. Moreover, appropriate technologies are required for the manufacture of building habitats for extended stays of astronauts on the Moon and Mars, as well as material/feedstock. The capacities for sending equipment and material into space are not only very limited and costly, but also raise concerns regarding environmental issues on Earth. Accordingly, not all materials can be sent from Earth, and strategies for the use of in-situ resources, i.e., in-situ resource utilization (ISRU), are being envisioned. For the manufacturing of both complex parts and equipment, as well as for large infrastructure, appropriate technologies for material processing in space need to be developed
Sub-second periodic radio oscillations in a microquasar
Powerful relativistic jets are one of the ubiquitous features of accreting
black holes in all scales. GRS 1915+105 is a well-known fast-spinning
black-hole X-ray binary with a relativistic jet, termed as a ``microquasar'',
as indicated by its superluminal motion of radio emission. It exhibits
persistent x-ray activity over the last 30 years, with quasi-periodic
oscillations of Hz and 34 and 67 Hz in the x-ray band. These
oscillations likely originate in the inner accretion disk, but other origins
have been considered. Radio observations found variable light curves with
quasi-periodic flares or oscillations with periods of minutes.
Here we report two instances of 5 Hz transient periodic oscillation
features from the source detected in the 1.05-1.45 GHz radio band that occurred
in January 2021 and June 2022, respectively. Circular polarization was also
observed during the oscillation phase.Comment: The author version of the article which will appear in Nature on 26
July 2023, 32 pages including the extended data. The online publication
version can be found at the following URL:
https://www.nature.com/articles/s41586-023-06336-
Follicular Oocytes Better Support Development in Rabbit Cloning Than Oviductal Oocytes
This study was conducted to determine the effect of rabbit oocytes collected from ovaries or oviducts on the developmental potential of nuclear transplant embryos. Donor nuclei were obtained from adult skin fibroblasts, cumulus cells, and embryonic blastomeres. Rabbit oocytes were flushed from the oviducts (oviductal oocytes) or aspirated from the ovaries (follicular oocytes) of superovulated does at 10, 11, or 12-h post-hCG injection. The majority of collected oocytes were still attached to the sites of ovulation on the ovaries. We found that follicular oocytes had a significantly higher rate of fusion with nuclear donor cells than oviductal oocytes. There was no difference in the cleavage rate between follicular and oviductal groups, but morula and blastocyst development was significantly higher in the follicular group than in the oviductal group. Two live clones were produced in follicular group using blastomere and cumulus nuclear donors, whereas one live clone was produced in the oviductal group using a cumulus nuclear donor. These results demonstrate that cloned rabbit embryos derived from follicular oocytes have better developmental competence than those derived from oviductal oocytes.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90481/1/cell-2E2011-2E0030.pd
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