Adaptive formation control for obstacle avoidance of USVs with asymmetric input saturation.

Due to the complex maritime navigation environment, Unmanned Surface Vessels (USVs) are influenced by unknown nonlinear dynamics arising from external disturbances and internal uncertainties. Achieving effective formation control while maintaining obstacle avoidance performance presents significant challenges. This article proposes a Neural Networks (NNs) adaptive formation Artificial Potential Field (APF) obstacle avoidance control method for multiple USVs.

Research on Drivers and Barriers to the Implementation of Cold Ironing Technology in Zero Emissions Port.

Ports play an important role in connecting the domestic and global economies. Zero emissions port models are actively developed and frequently utilized to fulfill economic objectives while reducing environmental effect. The cold ironing system is one of technological methods assisting ports in transitioning to zero emissions port models.

Assessment of the level and risk of radioactive hazards in coastal sediments in northern Vietnam.

Radioactivity in coastal sediments in northern Vietnam was examined using data from five sediment cores to assess radioactivity concentrations and radiation risk indices. Radiation risk indices included radium equivalent activity (Ra), the absorbed dose rate (ADR), the annual effective dose equivalent (AEDE), the activity utilization index (AUI), the external hazard index (H), the representative level gamma index (I), and the annual gonadal effective dose rate (AGDE). The radioactivity concentrations of K, Th, Ra, U, and Cs were 567, 56.

Dataset for analysing the ESG-oriented technical efficiency of VNSI listed companies.

In tandem with the evolution of the "green economy and finance" paradigm, a number of sustainability assessment metrics tailored to businesses has been meticulously researched and refined. Among the established benchmarks, the Environmental, Social, and Governance (ESG) index has emerged prominently. With the strategic guidance of governments across diverse nations, this index has progressively assumed a central role as a guiding compass for enterprises with aspirations of sustainable development and the pursuit of long-term investment strategies coveted by discerning investors.

Investigating the Drivers of the Reverse Logistics Implementation in Reducing Waste in Vietnam.

Reverse logistics systems are now acknowledged as being crucial for enterprises to enhance their overall financial and environmental performance, particularly in developing nations where they face more challenges on both fronts. The majority of researchers examined drivers and barriers to implementation in developed nations. This study aims to investigate the main factors that positively influence the practice of reverse logistics in a developing country such as Vietnam.

Electronic and optical properties of the hydrogen boride sheet from the many-body perturbation theory.

We study the electronic and optical properties of the hydrogen boride sheet by using the many-body perturbation theory with the perturbative(G0W0) approximation. It was found that the hydrogen boride sheet shows a semimetallic electronic structure, supporting the previous theoretical study based on the semilocal density functional theory calculations. It was also found that the optical spectrum calculated based on the quasiparticle energies agrees well with the experiments.

Novel gain-tuning for sliding mode control of second-order mechanical systems: theory and experiments.

The sliding mode control is well-known as a useful control technique that can be applied in several real-world applications. However, a straightforward and efficient process of selecting the sliding mode control gains remains a challenging but interesting topic. This paper investigates a novel gain tuning method for the sliding mode control of second-order mechanical systems.

Steam explosion as sustainable biomass pretreatment technique for biofuel production: Characteristics and challenges.

The biorefining process of lignocellulosic biomass has recently emerged as one of the most profitable biofuel production options. However, pretreatment is required to improve the recalcitrant lignocellulose's enzymatic conversion efficiency. Among biomass pretreatment methods, the steam explosion is an eco-friendly, inexpensive, and effective approach to pretreating biomass, significantly promoting biofuel production efficiency and yield.

Assessment of the distribution and ecological risks of heavy metals in coastal sediments in Vietnam's Mong Cai area.

Coastal sediments in the Mong Cai area were collected and analyzed for grain size, heavy metals, total organic carbon, and isotopes (Pb, Ra, δN, δC) to assess sediment quality. The most common sediments were fine sand in surface sediment, very fine sand in core C1, and very coarse and coarse silt in core C2. The total organic carbon was highest in C2 next to the surface and lowest in C1, with content levels of 1.

Data for the link between HEXACO personality traits and job search outcomes in Vietnam.

The purpose of this research data is to mention a correlation matrix of data-analytic estimates between the HEXACO personality traits and number of job interviews and job offers through job search networking behavior. The data-analytic correlations are based on 773 graduated students in universities in the North of Vietnam. This data used self-report surveys to collect the data.

Designing a novel heterostructure AgInS@MIL-101(Cr) photocatalyst from PET plastic waste for tetracycline degradation.

Semiconductor-containing porous materials with a well-defined structure could be unique scaffolds for carrying out selective organic transformations driven by visible light. We herein introduce for the first time a heterostructure of silver indium sulfide (AgInS) ternary chalcogenide and a highly porous MIL-101(Cr) metal-organic framework (MOF) synthesised from polyethylene terephthalate plastic waste. Our results demonstrate that AgInS nanoparticles were uniformly attached to each lattice plane of the octahedral MIL-101(Cr) structure, resulting in a nanocomposite with a high distribution of semiconductors in a porous media.

Hydrothermal carbonization of food waste as sustainable energy conversion path.

Every day, a large amount of food waste (FW) is released into the environment, causing financial loss and unpredictable consequences in the world, highlighting the urgency of finding a suitable approach to treating FW. As moisture content makes up 75% of the FW, hydrothermal carbonization (HTC) is a beneficial process for the treatment of FW since it does not require extensive drying. Moreover, the process is considered favorable for carbon sequestration to mitigate climate change in comparison with other processes because the majority of the carbon in FW is integrated into hydrochar.

Computational Analysis of Correlations between Image Aesthetic and Image Naturalness in the Relation with Image Quality.

The main purpose of this paper is the study of the correlations between Image Aesthetic (IA) and Image Naturalness (IN) and the analysis of the influence of IA and IN on Image Quality (IQ) in different contexts. The first contribution is a study about the potential relationships between IA and IN. For that study, two sub-questions are considered.

Photoreduction of CO to CH over Efficient Z-Scheme -FeO/g-CN Composites.

A series of composite -FeO/g-CN (denoted as xFeCN with equal 5, 10, 15, and 20 of -FeO percentage in weight) was prepared by calcination and precipitation-impregnation methods. X-ray diffraction (XRD), Fourier transform infrared (FTIR), and X-ray photoelectron spectrometry (XPS) characterizations indicated the successful synthesis of Z-scheme FeCN composites. A red shift of the light absorption region was revealed by UV-vis diffuse reflectance spectroscopy (UV-DRS).

Adsorption of toxic gases on borophene: surface deformation links to chemisorptions.

β borophene has received great attention because of its intriguing mechanical and electronic properties. One of the possible applications of borophene is gas sensing. However, the interaction between common gases and β borophene remains to be clarified.

Self-Assembly of Porphyrin Nanofibers on ZnO Nanoparticles for the Enhanced Photocatalytic Performance for Organic Dye Degradation.

Synthesizing novel photocatalysts that can effectively harvest photon energy over a wide range of the solar spectrum for practical applications is vital. Porphyrin-derived nanostructures with properties similar to those of chlorophyll have emerged as promising candidates to meet this requirement. In this study, tetrakis(4-carboxyphenyl) porphyrin (TCPP) nanofibers were formed on the surface of ZnO nanoparticles using a simple self-assembly approach.

Image Aesthetic Assessment Based on Image Classification and Region Segmentation.

The main goal of this paper is to study Image Aesthetic Assessment (IAA) indicating images as high or low aesthetic. The main contributions concern three points. Firstly, following the idea that photos in different categories (human, flower, animal, landscape, …) are taken with different photographic rules, image aesthetic should be evaluated in a different way for each image category.

Sorbent-based devices for the removal of spilled oil from water: a review.

Always, oil spills do cause serious and dire consequences for the environment, nature, and society that it consumes much time and socio-economic resources to overcome such consequences. Oil spills, hence, posed a big challenge in searching the advanced technologies and devices to recover spilled oil rapidly and efficiently. Indeed, sorbents have been found to play an extremely critical role in the spilled-oil remediation processes.

Advanced super-hydrophobic polymer-based porous absorbents for the treatment of oil-polluted water.

The threat of environmental pollution caused by spilled oil is rapidly increasing along with the expansion of oil exploration, the development of maritime activities and industrial growth. Oil spill incidents usually affect seriously the ecosystem and human life. Therefore, the treatment and recovery of the oil spill have been considered as an ultra-important issue to protect the environment and to minimize its negative impacts on socio-economic activities.

Synthesis of ZnO/Au Nanorods for Self Cleaning Applications.

Zinc oxide (ZnO) is a well-known semiconductor with valuable characteristics: wide direct band gap of ˜3.3 eV, large exciton binding energy of 60 meV at room temperature, high efficient photocatalyst, etc. which have been applied in many fields such as optical devices (LEDs, laser), solar cells and sensors.

Robust Position Control of an Over-actuated Underwater Vehicle under Model Uncertainties and Ocean Current Effects Using Dynamic Sliding Mode Surface and Optimal Allocation Control.

Underwater vehicles (UVs) are subjected to various environmental disturbances due to ocean currents, propulsion systems, and un-modeled disturbances. In practice, it is very challenging to design a control system to maintain UVs stayed at the desired static position permanently under these conditions. Therefore, in this study, a nonlinear dynamics and robust positioning control of the over-actuated autonomous underwater vehicle (AUV) under the effects of ocean current and model uncertainties are presented.

Carbon Nanomaterial-Based Nanofluids for Direct Thermal Solar Absorption.

Recently, many scientists have been making remarkable efforts to enhance the efficiency of direct solar thermal absorption collectors that depends on working fluids. There are a number of heat transfer fluids being investigated and developed. Among these fluids, carbon nanomaterial-based nanofluids have become the candidates with the most potential by the heat absorbing and transfer properties of the carbon nanomaterials.

Scalable Fabrication of Modified Graphene Nanoplatelets as an Effective Additive for Engine Lubricant Oil.

The use of nano-additives is widely recognized as a cheap and effective pathway to improve the performance of lubrication by minimizing the energy loss from friction and wear, especially in diesel engines. In this work, a simple and scalable protocol was proposed to fabricate a graphene additive to improve the engine lubricant oil. Graphene nanoplates (GNPs) were obtained by a one-step chemical exfoliation of natural graphite and were successfully modified with a surfactant and an organic compound to obtain a modified GNP additive, that can be facilely dispersed in lubricant oil.

A Self-Powered and Low Pressure Loss Gas Flowmeter Based on Fluid-Elastic Flutter Driven Triboelectric Nanogenerator.

A self-powered and low pressure loss gas flowmeter is presently proposed and developed based on a membrane's flutter driven triboelectric nanogenerator (TENG). Such a flowmeter, herein named "TENG flowmeter", is made of a circular pipe in which two copper electrodes are symmetrically fixed and a nonconductive, thin membrane is placed in the middle plane of the pipe. When a gas flows through the pipe at a sufficiently high speed, the membrane will continuously oscillate between the two electrodes, generating a periodically fluctuating electric voltage whose frequency can be easily measured.