740 research outputs found
An Equal-Size Hard EM Algorithm for Diverse Dialogue Generation
Open-domain dialogue systems aim to interact with humans through natural
language texts in an open-ended fashion. Despite the recent success of super
large dialogue systems such as ChatGPT, using medium-to-small-sized dialogue
systems remains the common practice as they are more lightweight and
accessible; however, generating diverse dialogue responses is challenging,
especially with smaller models. In this work, we propose an Equal-size Hard
Expectation--Maximization (EqHard-EM) algorithm to train a multi-decoder model
for diverse dialogue generation. Our algorithm assigns a sample to a decoder in
a hard manner and additionally imposes an equal-assignment constraint to ensure
that all decoders are well-trained. We provide detailed theoretical analysis to
justify our approach. Further, experiments on two large-scale open-domain
dialogue datasets verify that our EqHard-EM algorithm generates high-quality
diverse responses.Comment: Accepted by ICLR 202
Exponential stability for formation control systems with generalized controllers: A unified approach
This paper discusses generalized controllers for distance-based rigid formation shape stabilization and aims to provide a unified approach for the convergence analysis. We consider two types of formation control systems according to different characterizations of target formations: minimally rigid target formation and non-minimally rigid target formation. For the former case, we firstly prove the local exponential stability for rigid formation systems when using a general form of shape controllers with certain properties. From this viewpoint, different formation controllers proposed in previous literature can be included in a unified framework. We then extend the result to the case that the target formation is non-minimally rigid, and show that exponential stability of the formation system is still guaranteed with generalized controllers
EBBS: An Ensemble with Bi-Level Beam Search for Zero-Shot Machine Translation
The ability of zero-shot translation emerges when we train a multilingual
model with certain translation directions; the model can then directly
translate in unseen directions. Alternatively, zero-shot translation can be
accomplished by pivoting through a third language (e.g., English). In our work,
we observe that both direct and pivot translations are noisy and achieve less
satisfactory performance. We propose EBBS, an ensemble method with a novel
bi-level beam search algorithm, where each ensemble component explores its own
prediction step by step at the lower level but they are synchronized by a "soft
voting" mechanism at the upper level. Results on two popular multilingual
translation datasets show that EBBS consistently outperforms direct and pivot
translations as well as existing ensemble techniques. Further, we can distill
the ensemble's knowledge back to the multilingual model to improve inference
efficiency; profoundly, our EBBS-based distillation does not sacrifice, or even
improves, the translation quality
EUCLIA - Exploring the UV/optical continuum lag in active galactic nuclei. I. a model without light echoing
The tight inter-band correlation and the lag-wavelength relation among
UV/optical continua of active galactic nuclei have been firmly established.
They are usually understood within the widespread reprocessing scenario,
however, the implied inter-band lags are generally too small. Furthermore, it
is challenged by new evidences, such as the X-ray reprocessing yields too much
high frequency UV/optical variations as well as it fails to reproduce the
observed timescale-dependent color variations among {\it Swift} lightcurves of
NGC 5548. In a different manner, we demonstrate that an upgraded inhomogeneous
accretion disk model, whose local {\it independent} temperature fluctuations
are subject to a speculated {\it common} large-scale temperature fluctuation,
can intrinsically generate the tight inter-band correlation and lag across
UV/optical, and be in nice agreement with several observational properties of
NGC 5548, including the timescale-dependent color variation. The emergent lag
is a result of the {\it differential regression capability} of local
temperature fluctuations when responding to the large-scale fluctuation. An
average speed of propagations as large as of the speed of light
may be required by this common fluctuation. Several potential physical
mechanisms for such propagations are discussed. Our interesting
phenomenological scenario may shed new light on comprehending the UV/optical
continuum variations of active galactic nuclei.Comment: 18 pages, 8 figures. ApJ accepted. Further comments are very welcome
PAEDID: Patch Autoencoder Based Deep Image Decomposition For Pixel-level Defective Region Segmentation
Unsupervised pixel-level defective region segmentation is an important task
in image-based anomaly detection for various industrial applications. The
state-of-the-art methods have their own advantages and limitations:
matrix-decomposition-based methods are robust to noise but lack complex
background image modeling capability; representation-based methods are good at
defective region localization but lack accuracy in defective region shape
contour extraction; reconstruction-based methods detected defective region
match well with the ground truth defective region shape contour but are noisy.
To combine the best of both worlds, we present an unsupervised patch
autoencoder based deep image decomposition (PAEDID) method for defective region
segmentation. In the training stage, we learn the common background as a deep
image prior by a patch autoencoder (PAE) network. In the inference stage, we
formulate anomaly detection as an image decomposition problem with the deep
image prior and domain-specific regularizations. By adopting the proposed
approach, the defective regions in the image can be accurately extracted in an
unsupervised fashion. We demonstrate the effectiveness of the PAEDID method in
simulation studies and an industrial dataset in the case study
The universal "heartbeat" oscillations in black hole systems accross the mass-scale
The hyperluminous X-ray source (HLX-1, the peak X-ray luminosity ) near the spiral galaxy ESO 243-49 is possibly the best
candidate for intermediate mass black hole (IMBH), which underwent recurrent
outbursts with a period of days. The physical reason for this
quasi-periodic variability is still unclear. We explore the possibility of
radiation-pressure instability in accretion disk by modeling the light curve of
HLX-1, and find that it can roughly reproduce the duration, period and
amplitude of the recurrent outbursts HLX-1 with an IMBH of ~10^5Msun. Our
result provides a possible mechanism to explain the recurrent outbursts in
HLX-1. We further find a universal correlation between the outburst duration
and the bolometric luminosity for the BH sources with a very broad mass range
(e.g., X-ray binaries, XRBs, HLX-1 and active galactic nuclei, AGNs), which is
roughly consistent with the prediction of radiation-pressure instability of the
accretion disk. These results imply that "heartbeat" oscillations triggered by
radiation-pressure instability may appears in different-scale BH systems.Comment: ApJ in press; 15 pages, 5 Figure
VISION Datasets: A Benchmark for Vision-based InduStrial InspectiON
Despite progress in vision-based inspection algorithms, real-world industrial
challenges -- specifically in data availability, quality, and complex
production requirements -- often remain under-addressed. We introduce the
VISION Datasets, a diverse collection of 14 industrial inspection datasets,
uniquely poised to meet these challenges. Unlike previous datasets, VISION
brings versatility to defect detection, offering annotation masks across all
splits and catering to various detection methodologies. Our datasets also
feature instance-segmentation annotation, enabling precise defect
identification. With a total of 18k images encompassing 44 defect types, VISION
strives to mirror a wide range of real-world production scenarios. By
supporting two ongoing challenge competitions on the VISION Datasets, we hope
to foster further advancements in vision-based industrial inspection
High-Sensitivity C-Reactive Protein: An Independent Risk Factor for Left Ventricular Hypertrophy in Patients with Lupus Nephritis
Objective. To determine the prevalence of left ventricular hypertrophy (LVH) and its associated risk factors in lupus nephritis (LN) patients. Methods. 287 LN patients (age: 38.54 ± 13.31, 262 female) were recruited. Echocardiography and serum high-sensitivity C-reactive protein (hs-CRP) were measured. Their relationship was evaluated by univariate correlation analysis and multivariate regression analysis.
Results. The prevalence of LVH in this cohort was 21.25% (n = 61). Serum hs-CRP level was significantly elevated in patients with LVH compared to those without (8.03 (3.22–30.95) versus 3.93 (1.48–9.48) mg/L, P < .01), and correlated with left ventricular mass index (LVMI) (r = 0.314, P = .001). Multivariate regression analysis further confirmed that hs-CRP was an independent risk factor (β = 0.338, P = .002) for LVH in patients with LN. Conclusions. Our findings demonstrated that serum hs-CRP level is independently correlated with LVMI and suggested that measurement of hs-CRP may provide important clinical information to investigate LVH in LN patients
Serum IL-18 Is Closely Associated with Renal Tubulointerstitial Injury and Predicts Renal Prognosis in IgA Nephropathy
Background. IgA nephropathy (IgAN) was thought to be benign but recently found it slowly progresses and leads to ESRD eventually. The aim of this research is to investigate the value of serum IL-18 level, a sensitive biomarker for proximal tubule injury, for assessing the histopathological severity and disease progression in IgAN.
Methods. Serum IL-18 levels in 76 IgAN patients and 36 healthy blood donors were measured by ELISA. We evaluated percentage of global and segmental sclerosis (GSS) and extent of tubulointerstitial damage (TID). The correlations between serum IL-18 levels with clinical, histopathological features and renal prognosis were evaluated. Results. The patients were 38.85 ± 10.95
years old, presented with 2.61 (1.43∼4.08) g/day proteinuria. Serum IL-18 levels were significantly elevated in IgAN patients. Baseline serum IL-18 levels were significantly correlated with urinary protein excretion (r = 0.494, P = 0.002), Scr (r = 0.61, P < 0.001), and eGFR (r = −0.598, P < 0.001). TID scores showed a borderline significance with serum IL-18 levels (r = 0.355, P = 0.05). During follow-up, 26 patients (34.21%) had a declined renal function. Kaplan-Meier analysis found those patients with elevated IL-18 had a significant poor renal outcome (P = 0.03), and Cox analysis further confirmed that serum IL-18 levels were an independent predictor of renal prognosis (β = 1.98, P = 0.003)
Bastimolide B, an Antimalarial 24-Membered Marine Macrolide Possessing a tert-Butyl Group
We reported previously the discovery of the potent antimalarial 40-membered macrolide bastimolide A (1) from the tropical marine cyanobacterium Okeania hirsute. Continued investigation has led to the discovery of a new analogue, bastimolide B (2), a 24-membered polyhydroxy macrolide with a long aliphatic chain and unique terminal tertbutyl group. Its complete structure was determined by a combination of extensive spectroscopic methods and comparative analysis of its methanolysis products with those of bastimolide A. A methanolysis mechanism for bastimolide A is proposed, and one unexpected isomerization product of the C2−C3 double bond, 2-(E)-bastimolide A (3), was obtained. Bastimolide B (2) showed strong antimalarial activity against chloroquine-sensitive Plasmodium falciparum strain HB3. A preliminary investigation of the structure−activity relationship based on six analogues revealed the importance of the double bond as well as the 1,3-diol and 1,3,5-triol functionalities.We reported previously the discovery of the potent antimalarial 40-membered macrolide bastimolide A (1) from the tropical marine cyanobacterium Okeania hirsute. Continued investigation has led to the discovery of a new analogue, bastimolide B (2), a 24-membered polyhydroxy macrolide with a long aliphatic chain and unique terminal tertbutyl group. Its complete structure was determined by a combination of extensive spectroscopic methods and comparative analysis of its methanolysis products with those of bastimolide A. A methanolysis mechanism for bastimolide A is proposed, and one unexpected isomerization product of the C2−C3 double bond, 2-(E)-bastimolide A (3), was obtained. Bastimolide B (2) showed strong antimalarial activity against chloroquine-sensitive Plasmodium falciparum strain HB3. A preliminary investigation of the structure−activity relationship based on six analogues revealed the importance of the double bond as well as the 1,3-diol and 1,3,5-triol functionalities
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