Modified Decentralized Control for Multiphase Converters

Quoc-Dung Phan,An-Nhuan Le,Dinh-Tuyen Nguyen,Minh-Thien Nguyen,Guillaume Gateau 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5

In this paper, the modified decentralized modulation for the control of multiphase converters using phase-shifted carriers is presented. In difference of principle using local interconnections from two neighbor independent elementary controllers in the conventional decentralized control, the proposed method uses local informations from only one neighbor independent elementary controller allowing them to self-align their own carriers regardless the number of actives cells. Moreover, the same principle is applied for decentralized current control in the parallel phases in order to achieve a perfect sharing of the output current. The simulation results show the feasibility and effectiveness of the proposed method.

A Hybrid Fault-Tolerant Routing based on Gaussian Network for Wireless Sensor Network

Dung Nguyen Quoc,Niansheng Liu,Donghui Guo 한국통신학회 2022 Journal of communications and networks Vol.24 No.1

In this paper, we have proposed a hybrid faulttolerantrouting to solve fault-tolerant issue in wireless sensornetworks (WSNs) based on hierarchical topology. The hierarchicaltopology is a combination of clustering and the labeling ofsensor nodes as Gaussian integers. Accordingly, the network areais divided into small square grids, the cluster head of each gridis represented by a Gaussian integer. These cluster heads areconnected together to create a Gaussian network. Through nodesymmetry, and the shortest distance in the Gaussian network,as well as the advantages of multi-path routing, this paperproposes a hybrid fault-tolerant clustering routing protocol basedon Gaussian network for wireless sensor network (FCGW). Thepurpose of FCGW is to improve fault tolerance, increase datareliability and reduce energy consumption for wireless sensornetworks. The experimental results of the proposed scheme showthat FCGW protocol has high data reliability. In addition, theFCGW protocol consumes about 48% of the energy in thenetwork, while other protocols consume 70% more energy.

A survey of IoT malware and detection methods based on static features

Quoc-Dung Ngo,Huy-Trung Nguyen,Van-Hoang Le,Doan-Hieu Nguyen 한국통신학회 2020 ICT Express Vol.6 No.4

Due to a lack of security design as well as the specific characteristics of IoT devices such as the heterogeneity of processor architecture, IoT malware detection has to deal with very unique challenges, especially on detecting cross-architecture IoT malware. Therefore, the IoT malware detection domain is the focus of research by the security community in recent years. There are many studies taking advantages of well-known dynamic or static analysis for detecting IoT malware; however, static-based methods are more effective when addressing the multi-architecture issue. In this paper, we give a thorough survey of static IoT malware detection. We first introduce the definition, evolution and security threats of IoT malware. Then, we summarize, compare and analyze existing IoT malware detection methods proposed in recent years. Finally, we carry out exactly the methods of existing studies based on the same IoT malware dataset and an experimental configuration to evaluate objectively and increasing the reliability of these studies in detecting IoT malware.

Treatment of surface water using cold plasma for domestic water supply

Dung Van Nguyen,Phong Quoc Ho,Toan Van Pham,Tuyen Van Nguyen,Lavane Kim 대한환경공학회 2019 Environmental Engineering Research Vol.24 No.3

This paper presents the results of using cold plasma to treat surface water for domestic use purpose. Experimental results showed that cold plasma was an effective method for destroying bacteria in water. After treatment with cold plasma, concentration of coliform and Escherichia coli dramatically reduced. Besides, cold plasma significantly removed water odor, increased dissolved oxygen and decreased the concentration of chemical oxygen demand. However, cold plasma significantly raised the concentration of nitrite and nitrate. Other disadvantages of treating with cold plasma were conductivity increase and pH reduction. Pretreatment steps of coagulation, flocculation, sedimentation and sand filtration followed by disinfection with cold plasma exhibited a high efficiency in surface water treatment. All parameters of surface water after treatment by using the prototype satisfied with the allowance standard of domestic water quality.

Generating High-Resolution Fire Images with Controllable Attributes via Generative Adversarial Networks

Nguyen Quoc Dung,Hakil Kim 제어로봇시스템학회 2022 제어로봇시스템학회 국제학술대회 논문집 Vol.2022 No.11

Obtaining realistic fire images using deep learning models and recent versions of Generative adversarial networks (GAN) has been proven to be a difficult task due to the unnatural appearance of the generated results. This paper provides a novel approach based on StarGANv2 to generate fire kernels from any input provided as a reference. In addition, a deep learning-based image blending technique performs the migration of the fire kernels to the target scenes. By using any input as a reference, the generated fire image could be controlled to accommodate different environmental factors, resulting in a diverse but equally pseudo-real synthetic dataset. The proposed method generates images that achieve better FID and LPIPS values than StarGANv2 for both a public dataset (AI Hub) and a privately-owned dataset (Visionin). In addition, YOLOv4 is used as a fire detection model to evaluate the synthetic data on improving the performance of the detected network. Compared to the model trained on the real data, the model trained on the combined dataset outperforms 2%∼14% higher.

Building Principles of High Voltage Relay Protection

Nguyen Doan Quoc Anh,Tran Hoang Quang Minh,Nguyen Quang Dung,Shmoilov A.V 보안공학연구지원센터 2016 International Journal of u- and e- Service, Scienc Vol.9 No.10

Main characteristic of relay protection (RP) is selectivity. The fullest realization of this characteristic is given on principle operation of differential protection. On the ground of this reason and analysis of the arc monitoring the short circuits, two principles of the building RP are formulated: usual metric (which is used for building all the types existing RP with measuring relays) and proposed logical principle (on which is built arc protection, on flash of the electric arc at short circuits (SC)). The differential metric principle RP is proved to be the most appropriate for building RP on logical scheme. There are compared factors existing RZ by the approximation to logical principle of the building RP. As special principle of the building RP is distinguished the distance protection. The advantage the logical scheme of the building RZ are discussed in contrast with existing metric.

Factors Affecting Night-Time Economic Development: Research in Hanoi, Vietnam

Ngoc Son NGUYEN(Ngoc Son NGUYEN ),Vu Hiep HOANG(Vu Hiep HOANG ),Quoc Dung NGO(Quoc Dung NGO ),Van Hoa HOANG(Van Hoa HOANG ) 한국유통과학회 2023 Asian Journal of Business Environment (AJBE) Vol.13 No.2

Purpose: The purpose of the study is to explore the factors which influence the night-time economic development in Hanoi, Vietnam. The results can help policymakers achieve a scientific basis to plan the development of night-time economy in Hanoi. Research design, data and methodology: The research model is developed from literature review with 7 independent variables, including natural conditions and resources, infrastructure, safety, environmental issues, promotion and international integration, development of sharing economy, and institution and policy. This model is then adjusted by exploratory factors analysis to have 4 new variables: Institution and environment, Infrastructure and safety, Promotion and sharing, and Nature and resources. The model is regressed based on the data of 463 observations of night-time economy in Hanoi, Vietnam. Results: Consistent with the current literature addressing night-time economy, the results show positive impacts of all of the independent variables studied. Conclusions: It is recommended for the local authorities to strengthen advertising and promoting investment for NTE development in Hanoi city and also enhance the role of state management in NTE activities by raising awareness of the state management apparatus towards a more open-minded multi-dimensional view of the NTE, developing the NTE to overcome the barrier of thinking “if it cannot be managed, it is forbidden” in state management agencies, and defining responsibilities and authority among state management agencies in the management of NTE activities and strengthening decentralization and decentralization of powers for localities in the management and development of NTE.

The Effects of Corporate Governance on Segment Reporting Disclosure: A Case Study in Vietnam

Quoc Thinh TRAN,Ngoc Khanh Dung NGUYEN,Xuan Thuy LE 한국유통과학회 2021 The Journal of Asian Finance, Economics and Busine Vol.8 No.4

Accounting information is essential for users. Useful information helps users to make appropriate investment-related decisions. Segment reporting disclosure plays a practical role for an investor in a business. The article data was surveyed by ordinary least squares to test the effects of corporate governance on the segment reporting disclosure. The article employed time-series data with 136 observations of the top 100 non-financial Vietnamese enterprises listed on the stock exchange in the period of 2018–2019. The research used two popular theories related to stakeholder and agency to explain the effects of factors on segment reporting disclosure. The results have identified two factors that have a positive impact on segment reporting disclosure, namely, the size of the board and the ratio of foreign members to the total number of the board. Accordingly, the managers of the top 100 Vietnamese listed enterprises should increase the number of board members as well as pay attention to the number of foreign members to contribute to improving the information disclosure on the segment reporting. It is the basis to improve the quality of information to ensure completeness and transparency. It contributes to attracting foreign investment to meet the trend of international economic integration.

Influence of Ownership Structure on Voluntary Accounting Information Disclosure: Evidence from Top 100 Vietnamese Companies

Quoc Thinh TRAN,Ngoc Khanh Dung NGUYEN,Xuan Thuy LE 한국유통과학회 2021 The Journal of Asian Finance, Economics and Busine Vol.8 No.1

Accounting information disclosure by enterprises is important for third-party entities (suppliers, creditors, banks, regulators, etc.). Voluntary accounting information disclosure (VAID) refers to additional information related to business activities shown on the annual report above and beyond the required information about business results and financial position as well as cash flow. This supports the stakeholders gaining useful information to make proper business decisions. The article examines the influence of ownership structure on the voluntary accounting information disclosure of the top 100 Vietnamese listed companies (VN100). Data collected by authors on regular annual reports totaled 425 observations from 2015 to 2019. The article uses OLS to test multivariate regression models with time-series data. The research results show that there are three variables affecting voluntary accounting information disclosure, of which foreign ownership and institution ownership have a positive impact, while concentration ownership has an opposite impact. Accordingly, the managers of VN100 should raise awareness in order to demonstrate the obligation of information providers to users to ensure clarity and completeness. The state agencies should encourage VN100 to enhance voluntary accounting information disclosure. This contributes to improve the information level of Vietnamese listed companies to embrace the trend of international economic integration.

Financial Ratios Affecting Disclosure Level in Interim Report of Vietnamese Listed Enterprises

TRAN, Quoc Thinh,NGUYEN, Ngoc Khanh Dung,TO, Pham Que Anh Korea Distribution Science Association 2020 The Journal of Asian Finance, Economics and Busine Vol.7 No.10

Disclosure level in interim financial reporting is important for information users to make business decisions. This has received much attention from the information users. The article is aimed at determining the factors of financial ratios, which impact on the disclosure level in interim financial reporting. The authors use the ordinary least squares to test. The sample consists of 418 VN100 over a 6-year period from 2014 to 2019. The results show that there are four factors that positively impact on the disclosure level in interim financial reporting: Enterprise size (SIZE); Liquidity (LIQI); Sales growth (GROW) and Profitability (ROE). The article proposes some policy recommendations to contribute to improving disclosure level in interim financial reporting. Accordingly, State Securities Commission of Vietnam should strengthen the regular inspection of VN100's disclosure level in interim financial reporting and also should enforce strict sanctions or may consider delisting in cases of listed enterprises with incomplete disclosure. The managers of VN100 need to raise the sense of responsibility of information providers to ensure adequate information in interim financial reporting. Investors should also pay attention to the financial ratios of VN100 such as firm size, return-on-equity, liquidity, and sales growth to get useful information and ensure sound business decisions.