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On HTLC-Based Protocols for Multi-Party Cross-Chain Swaps
In his 2018 paper, Herlihy introduced an atomic protocol for multi-party
asset swaps across different blockchains. His model represents an asset swap by
a directed graph whose nodes are the participating parties and edges represent
asset transfers, and rational behavior of the participants is captured by a
preference relation between a protocol's outcomes. Asset transfers between
parties are achieved using smart contracts. These smart contracts are quite
involved and they require storage and processing of a large number of paths in
the swap digraph, limiting practical significance of his protocol. His paper
also describes a different protocol that uses only standard hash time-lock
contracts (HTLC's), but this simpler protocol applies only to some special
types of digraphs. He left open the question whether there is a simple and
efficient protocol for cross-chain asset swaps in arbitrary digraphs. Motivated
by this open problem, we conducted a comprehensive study of \emph{HTLC-based
protocols}, in which all asset transfers are implemented with HTLCs. Our main
contribution is a full characterization of swap digraphs that have such
protocols
Observability of substructures in planet-forming disk in (sub)cm wavelength with SKA and ngVLA
Current imaging observations of protoplanetary disks using ALMA primarily
focus on the sub-millimeter wavelength, leaving a gap in effective
observational approaches for centimeter-sized dust, which is crucial to the
issue of planet formation. The forthcoming SKA and ngVLA may rectify this
deficiency. In this paper, we employ multi-fluid hydrodynamic numerical
simulations and radiative transfer calculations to investigate the potential of
SKA1-Mid, ngVLA, and SKA2 for imaging protoplanetary disks at sub-cm/cm
wavelengths. We create mock images with ALMA/SKA/ngVLA at multi-wavelengths
based on the hydrodynamical simulation output, and test different sensitivity
and spatial resolutions. We discover that both SKA and ngVLA will serve as
excellent supplements to the existing observational range of ALMA, and their
high resolution enables them to image substructures in the disk's inner region
( 5 au from the stellar). Our results indicate that SKA and ngVLA can be
utilized for more extended monitoring programs in the centimeter waveband.
While in the sub-centimeter range, ngVLA possesses the capability to produce
high-fidelity images within shorter observation times ( 1 hour on source
time) than previous research, holding potential for future survey observations.
We also discuss for the first time the potential of SKA2 for observing
protoplanetary disks at a 0.7 cm wavelength.Comment: 10 pages, 6 figures, accepted by ApJ. Welcome any comments and
suggestions
RACE-SM: Reinforcement Learning Based Autonomous Control for Social On-Ramp Merging
Autonomous parallel-style on-ramp merging in human controlled traffic
continues to be an existing issue for autonomous vehicle control. Existing
non-learning based solutions for vehicle control rely on rules and optimization
primarily. These methods have been seen to present significant challenges.
Recent advancements in Deep Reinforcement Learning have shown promise and have
received significant academic interest however the available learning based
approaches show inadequate attention to other highway vehicles and often rely
on inaccurate road traffic assumptions. In addition, the parallel-style case is
rarely considered. A novel learning based model for acceleration and lane
change decision making that explicitly considers the utility to both the ego
vehicle and its surrounding vehicles which may be cooperative or uncooperative
to produce behaviour that is socially acceptable is proposed. The novel reward
function makes use of Social Value Orientation to weight the vehicle's level of
social cooperation and is divided into ego vehicle and surrounding vehicle
utility which are weighted according to the model's designated Social Value
Orientation. A two-lane highway with an on-ramp divided into a taper-style and
parallel-style section is considered. Simulation results indicated the
importance of considering surrounding vehicles in reward function design and
show that the proposed model matches or surpasses those in literature in terms
of collisions while also introducing socially courteous behaviour avoiding near
misses and anti-social behaviour through direct consideration of the effect of
merging on surrounding vehicles.Comment: Updated explanation of TTC, page
On additive differential probabilities of the composition of bitwise exclusive-or and a bit rotation
Properties of the additive differential probability
of the composition of bitwise XOR and a bit
rotation are investigated, where the differences are expressed using addition
modulo . This composition is widely used in ARX constructions consisting
of additions modulo , bit rotations and bitwise XORs. Differential
cryptanalysis of such primitives may involve maximums of
, where some of its input or output differences are
fixed. Although there is an efficient way to calculate this probability
(Velichkov et al, 2011), many of its properties are still unknown. In this
work, we find maximums of , where the rotation is
one bit left/right and one of its input differences is fixed. Some symmetries
of are obtained as well. We provide all its
impossible differentials in terms of regular expression patterns and estimate
the number of them. This number turns out to be maximal for the one bit left
rotation and noticeably less than the number of impossible differentials of
bitwise XOR
A Knowledge-Injected Curriculum Pretraining Framework for Question Answering
Knowledge-based question answering (KBQA) is a key task in NLP research, and
also an approach to access the web data and knowledge, which requires
exploiting knowledge graphs (KGs) for reasoning. In the literature, one
promising solution for KBQA is to incorporate the pretrained language model
(LM) with KGs by generating KG-centered pretraining corpus, which has shown its
superiority. However, these methods often depend on specific techniques and
resources to work, which may not always be available and restrict its
application. Moreover, existing methods focus more on improving language
understanding with KGs, while neglect the more important human-like complex
reasoning. To this end, in this paper, we propose a general Knowledge-Injected
Curriculum Pretraining framework (KICP) to achieve comprehensive KG learning
and exploitation for KBQA tasks, which is composed of knowledge injection (KI),
knowledge adaptation (KA) and curriculum reasoning (CR). Specifically, the KI
module first injects knowledge into the LM by generating KG-centered
pretraining corpus, and generalizes the process into three key steps that could
work with different implementations for flexible application. Next, the KA
module learns knowledge from the generated corpus with LM equipped with an
adapter as well as keeps its original natural language understanding ability to
reduce the negative impacts of the difference between the generated and natural
corpus. Last, to enable the LM with complex reasoning, the CR module follows
human reasoning patterns to construct three corpora with increasing
difficulties of reasoning, and further trains the LM from easy to hard in a
curriculum manner. We provide an implementation of the general framework, and
evaluate the proposed KICP on four real-word datasets. The results demonstrate
that our framework can achieve higher performances.Comment: Accepted by WWW 202
Should the choice of BOIN design parameter p.tox only depend on the target DLT rate?
When the early stopping parameter n.earlystop is relatively small or the
cohortsize value is not optimized via simulation, it may be better to use p.tox
< 1.4 * target.DLT.rate, or try out different cohort sizes, or increase
n.earlystop, whichever is both feasible and provides better operating
characteristics. This is because if the cohortsize was not optimized via
simulation, even when n.earlystop = 12, the BOIN escalation/de-escalation rules
generated using p.tox = 1.4 * target.DLT.rate could be exactly the same as
those calculated using p.tox > 3 * target.DLT.rate, which might not be
acceptable for some pediatric trials targeting 10% DLT rate. The traditional
3+3 design stops the dose finding process when 3 patients have been treated at
the current dose level, 0 DLT has been observed, and the next higher dose has
already been eliminated. If additional 3 patients were required to be treated
at the current dose in the situation described above, the corresponding
boundary table could be generated using BOIN design with target DLT rates
ranging from 18% to 29%, p.saf ranging from 8% to 26%, and p.tox ranging from
39% to 99%. To generate the boundary table of this 3+3 design variant, BOIN
parameters also need to satisfy a set of conditions
The Carbon Isotopic Ratio and Planet Formation
We present the first detection of 13CCH in a protoplanetary disk (TW Hya).
Using observations of C2H we measure CCH/13CCH = 65 +/- 20 in gas with a CO
isotopic ratio of 12CO/13CO = 21 +/- 5 (Yoshida et al. 2022a). The TW Hya disk
exhibits a gas phase C/O that exceeds unity and C2H is the tracer of this
excess carbon. We confirm that the TW Hya gaseous disk exhibits two separate
carbon isotopic reservoirs as noted previously (Yoshida et al. 2022a). We
explore two theoretical solutions for the development of this dichotomy. One
model represents TW Hya today with a protoplanetary disk exposed to a cosmic
ray ionization rate that is below interstellar as consistent with current
estimates. We find that this model does not have sufficient ionization in cold
(T < 40 K) layers to activate carbon isotopic fractionation. The second model
investigates a younger TW Hya protostellar disk exposed to an interstellar
cosmic ray ionization rate. We find that the younger model has sources of
ionization deeper in a colder disk that generates two independent isotopic
reservoirs. One reservoir is 12C-enriched carried by methane/hydrocarbon ices
and the other is 13C-enriched carried by gaseous CO. The former potentially
provides a source of methane/hydrocarbon ices to power the chemistry that
generates the anomalously strong CH emission in this (and other) disk
systems in later stages. The latter provides a source of gaseous 13C-rich
material to generate isotopic enrichments in forming giant planets as recently
detected in the super-Jupiter TYC 8998-760-1 b by Zhang et al. (2021).Comment: 16 pages, 8 figures, accepted by the Astrophysical Journa
Meta-Cognitive Analysis: Evaluating Declarative and Procedural Knowledge in Datasets and Large Language Models
Declarative knowledge and procedural knowledge are two key parts in
meta-cognitive theory, and these two hold significant importance in
pre-training and inference of LLMs. However, a comprehensive analysis comparing
these two types of knowledge is lacking, primarily due to challenges in
definition, probing and quantitative assessment. In this paper, we explore from
a new perspective by providing ground-truth knowledge for LLMs and evaluating
the effective score. Through extensive experiments with widely-used datasets
and models, we get conclusions: (1) In most tasks, benefits from declarative
knowledge are greater than those from procedural knowledge. (2) Profits of
procedural knowledge are larger than declarative knowledge only in reasoning
tasks with simple logic. (3) As pre-training progresses and size increases,
model ability to utilize both kinds of knowledge significantly improves, but in
different speed. We do detailed analysis for the findings and this can provide
primary guidance for evaluation and enhancement of large language models.Comment: Accepted by LREC-COLING 2024 as a short pape
FedComLoc: Communication-Efficient Distributed Training of Sparse and Quantized Models
Federated Learning (FL) has garnered increasing attention due to its unique
characteristic of allowing heterogeneous clients to process their private data
locally and interact with a central server, while being respectful of privacy.
A critical bottleneck in FL is the communication cost. A pivotal strategy to
mitigate this burden is \emph{Local Training}, which involves running multiple
local stochastic gradient descent iterations between communication phases. Our
work is inspired by the innovative \emph{Scaffnew} algorithm, which has
considerably advanced the reduction of communication complexity in FL. We
introduce FedComLoc (Federated Compressed and Local Training), integrating
practical and effective compression into \emph{Scaffnew} to further enhance
communication efficiency. Extensive experiments, using the popular TopK
compressor and quantization, demonstrate its prowess in substantially reducing
communication overheads in heterogeneous settings
The Next Generation Virgo Cluster Survey (NGVS). XXVII.The Size and Structure of Globular Cluster Systems and their Connection to Dark Matter Halos
We study the size and structure of globular clusters (GC) systems of 118
early-type galaxies from the NGVS, MATLAS, and ACSVCS surveys. Fitting S\'ersic
profiles, we investigate the relationship between effective radii of GC systems
() and galaxy properties. GC systems are 2--4 times more
extended than host galaxies across the entire stellar mass range of our sample
(). The relationship between and galaxy stellar mass exhibits a characteristic "knee" at a stellar mass
of , similar to galaxy --stellar mass relationship.
We present a new characterization of the traditional blue and red GC color
sub-populations, describing them with respect to host galaxy color
(): GCs with similar colors to their hosts have a "red"
, and those significantly bluer GCs have a "blue" .
The GC populations with red , even in dwarf galaxies, are twice as
extended as the stars, suggesting that formation or survival mechanisms favor
the outer regions. We find a tight correlation between and the
total number of GCs, with intrinsic scatter dex spanning two and
three orders of magnitude in size and number, respectively. This holds for both
red and blue subpopulations, albeit with different slopes. Assuming that
correlates with , we find that the red GC systems have
effective radii of roughly 1-5\% , while the blue GC systems in
massive galaxies can have sizes as large as 10\% .
Environmental dependence on is also found, with lower density
environments exhibiting more extended GC systems at fixed mass.Comment: 28 pages, 18 Figures, 3 tables, accepted for publication in Ap