Journal of Science and Technique
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A NOVEL FRAMEWORK FOR HTTP/2 OVER MPQUIC: DESIGN AND IMPLEMENTATION
Get PDFThe growing demand for high-performance and reliable web communication has driven significant advancements in transport protocols. This paper introduces an innovative framework for deploying Hypertext Transfer Protocol Version 2 (HTTP/2) over Multipath QUIC (MPQUIC), designed to enhance data transmission efficiency in heterogeneous networks. By integrating HTTP/2’s multiplexing and prioritization capabilities with MPQUIC’s ability to utilize multiple network paths concurrently, the framework addresses critical challenges in stream scheduling and protocol compatibility. To validate its practicality, we design and implement several stream schedulers within the framework. Comprehensive experimental evaluations in Mininet-WiFi confirm the framework’s effectiveness and provide comparative insights into scheduler performance. This work lays a strong foundation for the future development of high-performance web browsing over MPQUIC
ENHANCING COPYRIGHT PROTECTION AND PROVENANCE IN NFTS WITH BLOCKCHAIN-INTEGRATED FREQUENCY-DOMAIN WATERMARKING
Get PDFThe rapid expansion of the Non-Fungible Token (NFT) market has underscored significant challenges in copyright protection and ownership authentication. While blockchain technology ensures the immutability and transparency of token transactions, the off-chain storage of metadata and original content remains a critical vulnerability, exposing NFTs to risks such as data loss, manipulation, and copyright disputes. In response to these challenges, this study proposes a blockchain-integrated watermarking framework that embeds resilient copyright information into digital assets via a general frequency-domain approach. The watermark is stored off-chain within the InterPlanetary File System (IPFS), while its associated Content Identifier (CID) is anchored in a smart contract, ensuring traceability of provenance and verification of authenticity. Comparative experiments with the Least Significant Bit (LSB) method demonstrate the superior robustness of the proposed frequency-domain technique against various attacks, including compression, noise, and image manipulation. The proposed framework significantly enhances copyright protection, facilitates transparent NFT provenance, and provides a scalable foundation for secure digital asset management within blockchain-based ecosystems
AMCF-NET: ADAPTIVE MULTI-SCALE CROSS-MODAL FUSION NETWORK FOR UAV-SATELLITE CROSS-VIEW LOCALIZATION
Get PDFCross-view localization between Unmanned Aerial Vehicle (UAV) and satellite imagery is crucial for autonomous navigation in GPS-denied environments. However, large domain gaps, including viewpoint discrepancies, scale variations, and appearance differences — pose significant challenges. In this paper, we propose the Adaptive Multi-scale Cross-modal Fusion Network (AMCF-Net), a novel approach that effectively addresses these limitations through a shared backbone architecture and adaptive fusion mechanisms. Unlike previous dual-backbone approaches that process UAV and satellite images separately, our method employs a unified FocalNet-Tiny backbone to extract cross-modal features, followed by a Spatially-adaptive Crossmodal Feature Fusion (AMCF) module that dynamically combines multi-scale similarities using learned adaptive weights. This shared representation learning enables better cross-modal alignment and significantly reduces computational overhead. Comprehensive experiments on the UL14 benchmark demonstrate that AMCF-Net achieves state-of-the-art performance, with a Relative Distance Score (RDS) of 78.12% and meter-level accuracy of 27.25% at 3 m, 50.16% at 5 m, 84.37% at 10 m, and finally 88.51% at 20 m. Ablation studies further validate the effectiveness of the shared backbone and adaptive fusion mechanism, demonstrating significant improvements over traditional separate processing approaches
NGHIÊN CỨU XÁC ĐỊNH THÔNG SỐ NHIỆT ĐỘNG HỌC SẢN PHẨM NỔ NHIÊN LIỆU METAN TRONG ĐỘNG CƠ NỔ
Get PDFBài báo trình bày cơ sở xây dựng mô hình tính toán, cho phép xác định trạng thái nhiệt động học sau mặt sóng nổ của hỗn hợp nhiên liệu hydrocarbon dựa trên giả thuyết Chapman-Jouget trong động cơ nổ. Kiểm chứng kết quả tính toán từ mô hình toán so với kết quả thực nghiệm đối với nhiên liệu metan – oxy. Nghiên cứu quy luật biến đổi các đặc trưng nổ của hỗn hợp nhiên liệu metan - không khí khi thay đổi điều kiện ban đầu, bao gồm tỷ lệ nhiên liệu và áp suất trước mặt sóng nổ. Xác định liệu tối ưu đối với hỗn hợp nhiên liệu metan – không khí . Thông qua khảo sát ảnh hưởng của áp suất ban đầu nhiên liệu, khẳng định tính ưu việt về năng lượng và kết cấu của động cơ nổ
EVALUATING HUMAN TOLERANCE UNDER THE EFFECT OF SHOCK WAVE PRESSURE FROM SURFACE EXPLOSIONS
Get PDFProtecting individuals and structures from the effects of blast loading is a critical challenge when calculating and designing defensive structures. Shock waves, fragments, and the acceleration of structures caused by explosions will cause lethal damage to humans, equipment, and structures. To ensure safety, studies and standards in Vietnam for calculating safe distances for construction and humans in mining operations and defence structure constructions have been implemented. However, detailed studies on the impact of blast wave pressure on humans, depending on the position, the posture of the victims, the direction of the blast loading, and varying degrees of impact due to weight, have not been specifically researched. Hence, this article will introduce and use UFC 3-340-02, "Structures to resist the effects of accidental explosions", to develop a procedure for assessing the safe distances for humans affected by the pressure of ground blast loading. The result can be applied to automatically estimate the survival probability of humans under the impact of blast loading on the ground
SEISMIC PERFORMANCE OF SUPERELASTIC BRACING SYSTEMS APPLIED TO STEEL FRAME STRUCTURES
Get PDFBracing systems have emerged as an effective solution for enhancing the resilience of steel frame structures under dynamic loads. Conventional steel bracings dissipate energy through bilinear hysteresis responses, ensuring structural safety but often resulting in significant residual displacements after strong earthquake impacts that necessitate costly maintenance and repairs. Shape memory alloys (SMAs), particularly superelastic alloys, have drawn interest due to their potential for both energy dissipation and self-centering capabilities. This study explores the use of SMA-based superelastic bracing systems in steel frame structures subject to seismic loading. Using nonlinear time-history analyses performed in ETABS, the study investigates the comparative response of conventional and superelastic bracing systems. The findings of this research suggest that SMA-based bracing systems may offer advantages in reducing column demands and residual displacements, indicating potential for further development in seismic design applications
EXPERIMENTAL EVALUATION OF NOISE REDUCTION EFFECTIVENESS OF SOUNDPROOFING PANEL SYSTEM
Get PDFMeasures to mitigate aviation noise at airports are increasingly critical, particularly for those near urban areas, requiring studies of effective noise reduction strategies. This article presents an experimental study evaluating and comparing the soundproofing efficiency of a 3 cm thick panel system made from different material combinations, including acoustic sonic felt, plywood, and black rubber. The study focuses on single-source noise with intensity levels equivalent to aircraft engine noise, measured at the noise measurement points recommended by ICAO. Through the shielding panel system, the noise level generated by the electrical blasting machine decreases linearly with the power of the noise source. The findings indicate that noise levels decrease proportionally as the power of the noise source is reduced. Among the tested configurations, the wood-felt-wood combination exhibited the highest sound insulation efficiency, reducing sound intensity levels by 9.48-7.58 dB, compared to 5.85-5.08 dB for the felt-wood-felt system and 5.42-3.14 dB for the uniform felt and black rubber system of the same thickness. These results provide an initial foundation for proposing effective soundproof panel combinations to mitigate both traffic and aviation noise
SYNTHESIS AND INVESTIGATION OF ANTIMICROORGANISM ACTIVITY OF MIRAMISTIN
No full textQuaternary ammonium compounds are known for their rich physicochemical and biological characteristics, and are widely used in many areas of life such as surface active properties and anti-microbial properties. Miramistin is a typical compound with full physicochemical and biological properties of quaternary amino compounds, has antimicrobial properties and is widely used in the medical and pharmaceutical fields. This article presents the results of research on the synthesis and optimization of the miramistin synthesis process based on the use of different starting compounds. In addition, the antimicroorganism properties of miramistin were tested and showed potential application as an antimicroorganism
OPTIMIZATION OF SYNTHESIS PARAMETERS AND CHARACTERIZATION OF 4,6-DIHYDROXY-2-METHYL PYRIMIDINE
Get PDF4,6-dihydroxy-2-methylpyrimidine (MPD) serves as a crucial precursor in the pharmaceutical industry and the synthesis of organic compounds and has recently gained attention as a key intermediate in the production of the energetic material FOX-7. A modern synthetic approach involves the condensation of acetamidinium chloride (C2H7ClN2) and diethyl malonate (C7H12O4) in an organic alkaline medium; however, limited data are available regarding the technological parameters that govern this process. In this study, the Taguchi experimental design method was employed to determine the optimal conditions for maximizing MPD yield. Validation experiments confirmed that the optimal parameters included a sodium methoxide concentration of 18%, a reaction time of 180 minutes, and a DEM/Ace·HCl molar ratio of 1.4. Under these conditions, a maximum MPD yield of 88.5% was achieved. The synthesized MPD was subsequently identified and characterized through nuclear magnetic resonance (NMR) spectroscopy, Fourier-transform infrared (FTIR) spectroscopy, and melting point determination. Additionally, powder X-ray diffraction (PXRD) analysis was conducted, with the PXRD pattern of MPD being reported for the first time, providing valuable structural insights into the synthesized compound
COMPARATIVE ANALYSIS OF TiO2 NANOTUBE LAYERS FORMED BY SINGLE- AND TWO-STEP ANODIZATION: SURFACE MORPHOLOGY, CORROSION RESISTANCE, AND CELLULAR RESPONSE
Get PDFThis study examines the influence of anodization procedures on the formation and properties of TiO₂ nanotube layers on commercially pure titanium (cp-Ti) for biomedical implant applications. Both single-step (TiO2 1S) and two-step (TiO2 2S) anodization produced nanotubular structures composed of anatase and rutile phases, with the two-step process yielding more uniform and vertically aligned nanotubes. Mechanical testing indicated an increase in surface hardness, while electrochemical analyses demonstrated enhanced corrosion resistance, particularly for the TiO2 2S sample. Furthermore, TiO2 2S surfaces promoted superior cell adhesion and spreading, with well-developed filopodia and lamellipodia. Overall, the two-step anodization produces a more stable, oxygen-rich oxide layer with improved durability and biocompatibility, highlighting its potential for bone implant applications