399 research outputs found
XFEM/Level-set for modelling of coated inclusion composites
In this paper, Extended Finite Element method (XFEM) is used to model the embedded coated inclusion composite. The coated inclusion with finite thickness is associated with two level-set functions, which describe its inside and outside interfaces. A simple integration rule is employed for numerical quadrature in elements cut by two interfaces. Accuracy and efficiency of the proposed approach are demonstrated through 3D numerical examples and applied to homogenization of such materials
The Relationship between Organizational Culture, Job Satisfaction, and Commitment of Lecturers at Universities
Purpose: The study aimed to determine the influence of factors on job satisfaction and the relationship between satisfaction, organizational culture, and the organizational commitment of lecturers at universities in Ho Chi Minh City. Design/Methodology/Approach: This was a quantitative study in which the authors compile theories, analyze and synthesize scales for research concepts, and propose research models. The online survey collected 532 answer sheets from professors and lecturers from universities in Ho Chi Minh City, of which 525 were valid and included in SmartPLS 3 to evaluate the validity and reliability of the scale and to analyze the relationship among the concepts in the suggested model. Findings: The results show that several factors significantly impact employee satisfaction in the field of education, such as job promotion, leadership or supervision, working environment, income, and the job itself. In addition, both satisfaction and organizational culture impact organizational commitment. The study's findings have implications for educational institutions, lecturers, policymakers, researchers, and funding agencies. They highlight the importance of factors like leadership development and organizational culture in enhancing job satisfaction and commitment among lecturers, offering valuable insights for improving the educational environment in Ho Chi Minh City and beyond. Originality: The results aligned with previous studies presented in the literature section. However, this study revealed some specific characteristics of lecturers in universities in Ho Chi Minh City, Vietnam, where lecturers focused on personal development but were committed to the organization via job satisfaction and culture. Doi: 10.28991/ESJ-2023-SIED2-021 Full Text: PD
Robust Diffusion GAN using Semi-Unbalanced Optimal Transport
Diffusion models, a type of generative model, have demonstrated great
potential for synthesizing highly detailed images. By integrating with GAN,
advanced diffusion models like DDGAN \citep{xiao2022DDGAN} could approach
real-time performance for expansive practical applications. While DDGAN has
effectively addressed the challenges of generative modeling, namely producing
high-quality samples, covering different data modes, and achieving faster
sampling, it remains susceptible to performance drops caused by datasets that
are corrupted with outlier samples. This work introduces a robust training
technique based on semi-unbalanced optimal transport to mitigate the impact of
outliers effectively. Through comprehensive evaluations, we demonstrate that
our robust diffusion GAN (RDGAN) outperforms vanilla DDGAN in terms of the
aforementioned generative modeling criteria, i.e., image quality, mode coverage
of distribution, and inference speed, and exhibits improved robustness when
dealing with both clean and corrupted datasets
SHEDDING TO GROW: THE COMING DOI MOI 2.0 IN VIETNAM’S FOREIGN POLICY
Purpose of the study: The purpose of this study is to revisit the characteristics of Vietnam’s foreign policy since its renovation in 1986, also known as Doi Moi, and explore its future trajectory in the coming decades.
Methodology: This study employs a well-established analytical framework relying on the two-level game theory in foreign policy analysis which denotes that a state’s foreign policy is shaped by both external and domestic factors. Primary data are collected from a wide range of trusted resources and databases and communications of the authors with Vietnamese veteran diplomats and foreign policymakers.
Main finding: This article finds that three decades since the launching of Doi Moi in 1986, fundamental principles of Vietnam’s foreign policy remains intact. Because both domestic and external foundations for the initial stage of renovation have fundamentally been replaced by new contexts, Hanoi will likely move towards the so-called Doi Moi 2.0 characterized by greater proactiveness and determination.
Applications of this study: This study has implication for policymakers, scholars and experts in the disciplines and subfields of politics, international relations, foreign policy analysis given that Vietnam has been well known for its significant achievements in its diplomatic relations after the Cold War and it is playing a growing role in regional and international affairs.
The originality of this study: This study makes an original contribution to the existing literature of Vietnam’s foreign policy because it digs into an issue where only a few numbers of scholars have touched upon and provides a comprehensive analysis of the factors influencing Hanoi’s mindset, shaping Vietnam’s national interests and formulating Vietnam’s foreign policy in the coming decades
India-China strategic competition in the Indian Ocean
The XXI is considered by major countries in the Asia-Pacific region as ‘the century of sea and ocean' and is accompanied by fierce competition among the nations to gain interest in the sea regions. On the basis that previously only considered the competition for military objectives, geostrategic bases and traffic channels through the straits, nowadays, countries worldwide have stepped up the competition for economic interests and marine resources. The development of military power and the competitive activities for resources at sea show clear the tendency to use the sea to contain the continent. In that context, the Indian Ocean, as the world's third largest ocean, has an important geographic location and rich and diverse natural resources; the arterial sea route is gradually becoming the center of new world geopolitics and an important area in the strategic competition between two 'Asian giants' - India and China. The competition between these countries in the Indian Ocean is growing and profoundly impacts the region's stability and security. This article focuses on the position and important role of the Indian Ocean in the policies of India and China, the fierce competition between the two countries in nearly two decades of the XXI century
Reducing Training Time in Cross-Silo Federated Learning using Multigraph Topology
Federated learning is an active research topic since it enables several
participants to jointly train a model without sharing local data. Currently,
cross-silo federated learning is a popular training setting that utilizes a few
hundred reliable data silos with high-speed access links to training a model.
While this approach has been widely applied in real-world scenarios, designing
a robust topology to reduce the training time remains an open problem. In this
paper, we present a new multigraph topology for cross-silo federated learning.
We first construct the multigraph using the overlay graph. We then parse this
multigraph into different simple graphs with isolated nodes. The existence of
isolated nodes allows us to perform model aggregation without waiting for other
nodes, hence effectively reducing the training time. Intensive experiments on
three public datasets show that our proposed method significantly reduces the
training time compared with recent state-of-the-art topologies while
maintaining the accuracy of the learned model. Our code can be found at
https://github.com/aioz-ai/MultigraphFLComment: accepted in ICCV 202
Joint Transaction Transmission and Channel Selection in Cognitive Radio Based Blockchain Networks: A Deep Reinforcement Learning Approach
To ensure that the data aggregation, data storage, and data processing are
all performed in a decentralized but trusted manner, we propose to use the
blockchain with the mining pool to support IoT services based on cognitive
radio networks. As such, the secondary user can send its sensing data, i.e.,
transactions, to the mining pools. After being verified by miners, the
transactions are added to the blocks. However, under the dynamics of the
primary channel and the uncertainty of the mempool state of the mining pool, it
is challenging for the secondary user to determine an optimal transaction
transmission policy. In this paper, we propose to use the deep reinforcement
learning algorithm to derive an optimal transaction transmission policy for the
secondary user. Specifically, we adopt a Double Deep-Q Network (DDQN) that
allows the secondary user to learn the optimal policy. The simulation results
clearly show that the proposed deep reinforcement learning algorithm
outperforms the conventional Q-learning scheme in terms of reward and learning
speed
Application of hybrid control algorithm for the vehicle active suspension system to reduce the vibration
This research proposes a hybrid control algorithm to enhance smoothness in a vehicle’s motion. The control signal is synthesized from two separate controllers, Proportional Integral Derivative (PID) and Sliding Mode Control (SMC), to achieve superior control performance. The novelty of the proposed control algorithm lies in using a double-loop algorithm to determine the controller parameters. The algorithm proposed in this research involves two computational processes to determine the model's optimal values including the raw value and the acceptable value. The proposed control algorithm has been simulated considering three specific cases corresponding to the three types of road stimuli. The results demonstrate that the values of sprung mass displacement and acceleration dropped considerably with the application of the proposed algorithm. Moreover, the change in vertical force at the wheel is also reduced with the application of the algorithm particularly in the third case where the vertical force at the wheel has reached to zero. The average values of vehicle body displacement are found to be 166.17mm (for passive case), 54.20mm (for PID) and 42.52mm (for SMC). The proposed control algorithm managed to reduce this value to 8.95mm as evidenced by simulation results. Finally, the response of the control system when subjected to an excitation signal from the road surface further demonstrates efficacy of the proposed hybrid control algorithm
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