184 research outputs found
Influence of Social Network Integration on the Online Review Helpfulness
Online consumer reviews are important for consumers when they make purchasing decisions. However, the large volume of online reviews makes it difficult for consumers to identify those helpful reviews. The influencing factors on online review helpfulness have drawn great attention from different research fields. In recent years, online review websites start to exhibit more features of social media. For example, some websites allow users to integrate with other social media accounts. The influences of such social factors, however, are rarely studied in the literature. Drawing on a dataset from Qunar.com, this paper explores how social network integration and reviewer network centrality influence online review helpfulness through a negative binomial regression model. Our results show that both factors have a positive effect on review helpfulness, and that network centrality positively moderates the effect of social network integration. Our research results provide important implications for reviewers, industry practitioners, and online review websites
Effects of Cations and PH on Antimicrobial Activity of Thanatin and s-Thanatin against _Escherichia coli_ ATCC25922 and _B. subtilis_ ATCC 21332
Thanatin and s-thanatin were insect antimicrobial peptides which have shown potent antimicrobial activities on a variety of microbes. In order to investigate the effect of cations and pH on the activity of these peptides against Gram-negative bacteria and Gram-positive bacteria, the antimicrobial activities of both peptides were studied in increasing concentrations of monovalent cations (K^+^ and Na^+^), divalent cations (Ca^2+^ and Mg^2+^) and H^+^. The NCCLS broth microdilution method showed that both peptides were sensitive to the presence of cations. The divalent cations showed more antagonized effect on the activity against Gram-negative bacteria than the monovalent cations, since the two peptides lost the ability to inhibit bacterial growth at a very low concentration. In addition, the activities of both peptides tested were not significantly affected by pH. Comparing to studies of other antibacterial peptide activities, our data support a hypothesis that positive ions affect the sensitivity to cation peptides
Concatenation of the Gottesman-Kitaev-Preskill code with the XZZX surface code
Bosonic codes provide an alternative option for quantum error correction. An
important category of bosonic codes called the Gottesman-Kitaev-Preskill (GKP)
code has aroused much interest recently. Theoretically, the error correction
ability of GKP code is limited since it can only correct small shift errors in
position and momentum quadratures. A natural approach to promote the GKP error
correction for large-scale, fault-tolerant quantum computation is concatenating
encoded GKP states with a stabilizer code. The performance of the XZZX
surface-GKP code, i.e., the single-mode GKP code concatenated with the XZZX
surface code is investigated in this paper under two different noise models.
Firstly, in the code-capacity noise model, the asymmetric rectangular GKP code
with parameter is introduced. Using the minimum weight perfect
matching decoder combined with the continuous-variable GKP information, the
optimal threshold of the XZZX-surface GKP code reaches when
, compared with the threshold of the standard
surface-GKP code. Secondly, we analyze the shift errors of two-qubit gates in
the actual implementation and build the full circuit-level noise model. By
setting the appropriate bias parameters, the logical error rate is reduced by
several times in some cases. These results indicate the XZZX surface-GKP codes
are more suitable for asymmetric concatenation under the general noise models.
We also estimate the overhead of the XZZX-surface GKP code which uses about 291
GKP states with the noise parameter 18.5 dB () to
encode a logical qubit with the error rate , compared with
the qubit-based surface code using 3041 qubits to achieve almost the same
logical error rate.Comment: 17 pages, 10 figure
The News Delivery Channel Recommendation Based on Granular Neural Network
With the continuous maturation and expansion of neural network technology,
deep neural networks have been widely utilized as the fundamental building
blocks of deep learning in a variety of applications, including speech
recognition, machine translation, image processing, and the creation of
recommendation systems. Therefore, many real-world complex problems can be
solved by the deep learning techniques. As is known, traditional news
recommendation systems mostly employ techniques based on collaborative
filtering and deep learning, but the performance of these algorithms is
constrained by the sparsity of the data and the scalability of the approaches.
In this paper, we propose a recommendation model using granular neural network
model to recommend news to appropriate channels by analyzing the properties of
news. Specifically, a specified neural network serves as the foundation for the
granular neural network that the model is considered to be build. Different
information granularities are attributed to various types of news material, and
different information granularities are released between networks in various
ways. When processing data, granular output is created, which is compared to
the interval values pre-set on various platforms and used to quantify the
analysis's effectiveness. The analysis results could help the media to match
the proper news in depth, maximize the public attention of the news and the
utilization of media resources
A Multi-Transformation Evolutionary Framework for Influence Maximization in Social Networks
Influence maximization is a crucial issue for mining the deep information of
social networks, which aims to select a seed set from the network to maximize
the number of influenced nodes. To evaluate the influence spread of a seed set
efficiently, existing studies have proposed transformations with lower
computational costs to replace the expensive Monte Carlo simulation process.
These alternate transformations, based on network prior knowledge, induce
different search behaviors with similar characteristics to various
perspectives. Specifically, it is difficult for users to determine a suitable
transformation a priori. This article proposes a multi-transformation
evolutionary framework for influence maximization (MTEFIM) with convergence
guarantees to exploit the potential similarities and unique advantages of
alternate transformations and to avoid users manually determining the most
suitable one. In MTEFIM, multiple transformations are optimized simultaneously
as multiple tasks. Each transformation is assigned an evolutionary solver.
Three major components of MTEFIM are conducted via: 1) estimating the potential
relationship across transformations based on the degree of overlap across
individuals of different populations, 2) transferring individuals across
populations adaptively according to the inter-transformation relationship, and
3) selecting the final output seed set containing all the transformation's
knowledge. The effectiveness of MTEFIM is validated on both benchmarks and
real-world social networks. The experimental results show that MTEFIM can
efficiently utilize the potentially transferable knowledge across multiple
transformations to achieve highly competitive performance compared to several
popular IM-specific methods. The implementation of MTEFIM can be accessed at
https://github.com/xiaofangxd/MTEFIM.Comment: This work has been submitted to the IEEE Computational Intelligence
Magazine for publication. Copyright may be transferred without notice, after
which this version may no longer be accessibl
Optimizing energy efficiency of CNN-based object detection with dynamic voltage and frequency scaling
On the one hand, accelerating convolution neural networks (CNNs) on FPGAs requires ever increasing high energy efficiency in the edge computing paradigm. On the other hand, unlike normal digital algorithms, CNNs maintain their high robustness even with limited timing errors. By taking advantage of this unique feature, we propose to use dynamic voltage and frequency scaling (DVFS) to further optimize the energy efficiency for CNNs. First, we have developed a DVFS framework on FPGAs. Second, we apply the DVFS to SkyNet, a state-of-the-art neural network targeting on object detection. Third, we analyze the impact of DVFS on CNNs in terms of performance, power, energy efficiency and accuracy. Compared to the state-of-the-art, experimental results show that we have achieved 38% improvement in energy efficiency without any loss in accuracy. Results also show that we can achieve 47% improvement in energy efficiency if we allow 0.11% relaxation in accuracy
Asynchronous Multi-Agent Reinforcement Learning for Efficient Real-Time Multi-Robot Cooperative Exploration
We consider the problem of cooperative exploration where multiple robots need
to cooperatively explore an unknown region as fast as possible. Multi-agent
reinforcement learning (MARL) has recently become a trending paradigm for
solving this challenge. However, existing MARL-based methods adopt
action-making steps as the metric for exploration efficiency by assuming all
the agents are acting in a fully synchronous manner: i.e., every single agent
produces an action simultaneously and every single action is executed
instantaneously at each time step. Despite its mathematical simplicity, such a
synchronous MARL formulation can be problematic for real-world robotic
applications. It can be typical that different robots may take slightly
different wall-clock times to accomplish an atomic action or even periodically
get lost due to hardware issues. Simply waiting for every robot being ready for
the next action can be particularly time-inefficient. Therefore, we propose an
asynchronous MARL solution, Asynchronous Coordination Explorer (ACE), to tackle
this real-world challenge. We first extend a classical MARL algorithm,
multi-agent PPO (MAPPO), to the asynchronous setting and additionally apply
action-delay randomization to enforce the learned policy to generalize better
to varying action delays in the real world. Moreover, each navigation agent is
represented as a team-size-invariant CNN-based policy, which greatly benefits
real-robot deployment by handling possible robot lost and allows
bandwidth-efficient intra-agent communication through low-dimensional CNN
features. We first validate our approach in a grid-based scenario. Both
simulation and real-robot results show that ACE reduces over 10% actual
exploration time compared with classical approaches. We also apply our
framework to a high-fidelity visual-based environment, Habitat, achieving 28%
improvement in exploration efficiency.Comment: This paper is accepted by AAMAS 2023. The source code can be found in
https://github.com/yang-xy20/async_mapp
The efficacy and safety of anti-Aβ agents for delaying cognitive decline in Alzheimer’s disease: a meta-analysis
BackgroundThis meta-analysis evaluates the efficacy and safety of amyloid-β (Aβ) targeted therapies for delaying cognitive deterioration in Alzheimer’s disease (AD).MethodsPubMed, EMBASE, the Cochrane Library, and ClinicalTrials.gov were systematically searched to identify relevant studies published before January 18, 2023.ResultsWe pooled 33,689 participants from 42 studies. The meta-analysis showed no difference between anti-Aβ drugs and placebo in the Alzheimer’s Disease Assessment Scale–Cognitive Subscale (ADAS-Cog), and anti-Aβ drugs were associated with a high risk of adverse events [ADAS-Cog: MDs = −0.08 (−0.32 to 0.15), p = 0.4785; AEs: RR = 1.07 (1.02 to 1.11), p = 0.0014]. Monoclonal antibodies outperformed the placebo in delaying cognitive deterioration as measured by ADAS-Cog, Clinical Dementia Rating–Sum of Boxes (CDR-SB), Mini-Mental State Examination (MMSE) and Alzheimer’s Disease Cooperative Study–Activities of Daily Living (ADCS-ADL), without increasing the risk of adverse events [ADAS-Cog: MDs = −0.55 (−0.89 to 0.21), p = 0.001; CDR-SB: MDs = −0.19 (−0.29 to −0.10), p < 0.0001; MMSE: MDs = 0.19 (0.00 to 0.39), p = 0.05; ADCS-ADL: MDs = 1.26 (0.84 to 1.68), p < 0.00001]. Intravenous immunoglobulin and γ-secretase modulators (GSM) increased cognitive decline in CDR-SB [MDs = 0.45 (0.17 to 0.74), p = 0.002], but had acceptable safety profiles in AD patients. γ-secretase inhibitors (GSI) increased cognitive decline in ADAS-Cog, and also in MMSE and ADCS-ADL. BACE-1 inhibitors aggravated cognitive deterioration in the outcome of the Neuropsychiatric Inventory (NPI). GSI and BACE-1 inhibitors caused safety concerns. No evidence indicates active Aβ immunotherapy, MPAC, or tramiprosate have effects on cognitive function and tramiprosate is associated with serious adverse events.ConclusionCurrent evidence does not show that anti-Aβ drugs have an effect on cognitive performance in AD patients. However, monoclonal antibodies can delay cognitive decline in AD. Development of other types of anti-Aβ drugs should be cautious.Systematic Review RegistrationPROSPERO (https://www.crd.york.ac.uk/prospero/), identifier CRD42023391596
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