History and applications of concrete steel composite structure

The composite steel-and-concrete structure is a modern structure, combines the advantages of concrete and steel one. Nowadays, it is widely utilized all over the world but not much in Vietnam. Studying the history of formation and development is very meaningful in understanding and applying this type of structure in practice. This article focuses on presenting the formation and development of the composite structure and, at the same time, introduces the potential and applications of the composite structure to the current construction practice in Vietnam

A Novel High-Speed Architecture for Integrating Multiple DDoS Countermeasure Mechanisms Using Reconfigurable Hardware

In this paper, we proposed a novel high-speed architecture to incorporate multiple stand-alone DDoS countering mechanisms. The architecture separates DDoS filtering mechanisms, which are algorithms, out of packet decoder, which is the basement. The architecture not only helps developers to give more concentration on optimizing algorithms but also integrate multiple algorithms to achieve more efficient DDoS defense mechanism. The architecture is implemented on reconfigurable hardware, which helps algorithms to be flexibly changed or updated. We implemented and experimented the system using NetFPGA 10G board with incorporation of Port Ingress/Egress Filtering and Hop-Count Filtering to classify IP spoofing packets. The synthesis results show that the system runs at 118.907 MHz, utilizes 38.99% Registers, and 44.75% BlockRAMs/FIFOs of the NetFPGA 10G board. The system achieves the detection rate of 100% with false negative rate at 0%, and false positive rate closed to 0.16%. The experimental results prove that the system achieves packet decoding throughput at 9.869 Gbps in half-duplex mode and 19.738 Gbps in full-duplex mode

Improving multiphase induction-heating systems: several configurations and resonant control show promise

This article presents a new configuration for multiphase induction-heating (IH) systems and their control schemes. Instead of using separate voltage inverters to supply the required current to the inductors in each phase, we specifically configured the inverters to reduce the number of power switches. A modification of the inverter-setting parameters ensured the proper operation of the system. We obtained the best references through a specific optimization procedure and tested several solutions for neutral current minimization, including a new arrangement of the coils. In addition, proportional-resonant (PR) controllers allowed us to achieve current control in the different phases. We developed the application on a reduced-power, three-phase coupled resonant test bench, which provided simulation and experimental results

FPGA-Based Multiple DDoS Countermeasure Mechanisms System Using Partial Dynamic Reconfiguration

In this paper, we propose a novel FPGA-based high-speed DDoS countermeasure system that can flexibly adapt to DDoS attacks while still maintaining system performance. The system includes a packet decoder module and multiple DDoS countermeasure mechanisms. We apply dynamic partial reconfiguration technique in this system so that the countermeasure mechanisms can be flexibly changed or updated on-the-fly. The proposed system architecture separates DDoS protection modules (which implement DDoS countermeasure techniques) from the packet decoder module. By using this approach, one DDoS protection module can be reconfigured without interfering with other modules. The proposed system is implemented on a NetFPGA 10G board. The synthesis results show that the system can work at up to 116.782 MHz while utilizing up to 39.9% Registers and 49.85% BlockRAM of the Xilinx Virtex xcv5tx240t FPGA device on the NetFPGA 10G board. The system achieves the detection rate of 100% with the false negative rate at 0% and false positive rate closed to 0.16%. The prototype system achieves packet decoding throughput at 9.869 Gbps in half-duplex mode and 19.738 Gbps in full-duplex mode

Identification of rose black spot pathogen in Sa Đéc city, Đồng Tháp province of Vietnam

Black spot is one of the most destructive diseases of roses, causing premature defoliation, thus progressively weakening the plant and even leading to death. This study aimed at identifying the pathogen causing black spot on Rosa chinensis Jacq. cv. nhung (Hồng Nhung) and R. chinensis Jacq. var. minima (Hồng Tỉ Muội) in Sa Đéc city, Đồng Tháp province, Vietnam, using a combination of conidia morphology and pathogenicity tests including detached leaf and intact plant techniques. A total of 32 infected leaf samples with the black spot typical symptoms were collected from six rose cultivation areas. The morphological characterization of the conidia obtained from these samples was elliptical, hyaline, two-celled and had vacuole-like structures, similar to those produced by Diplocarpon. In pathogenicity test, the symptoms were observed on cv. nhung but not var. minima in the detached leaf technique while symptoms were observed on both cultivars in intact plants technique. These included black spots with perforated edges, aggregating into bigger patches. The infected leaves could yellow and defoliate at 21 days after inoculation. Compared to the previous pathogenic studies and description of diseases on roses, the fungal pathogen was identified as fungus Diplocarpon rosae

LIGNANS FROM LEAVES OF AMESIODENDRON CHINENSE AND THEIR CYTOTOXIC ACTIVITY

ABSTRACTFrom leaves of Amesiodendron chinense (Mer.) Hu four lignans (+)-aptosimon (1), (+)-isolariciresinol (2), (-)-cleomiscosin A (3), and (-)-cleomiscosin C (3) were isolated. Their structures were determined by spectroscopic analysis including MS, 1D and 2D NMR as well as by comparison with reported data in literature. All compounds were evaluated for cytotoxic activities against five human cancer cell lines, KB, SK-LU-1, MCF-7, HepG-2, and SW-480. They showed weak cytotoxic activity on five tested human cancer cell lines with IC50 values ranging from 32.61 to 95.18 µg/ml

Phenolic compounds from leaves of Amensiodendron chinese (Sapindaceae)

From the ethyl acetate extract of the leaves of Amensiodendron chinense (Merr.) Hu (Sapindaceae), we isolated three known phenolic compounds: 4-hydroxy-3-methoxybenzaldehyde (1), methyl 3,4-dihydroxybenzoate (2), and 3,4-dihydroxybenzoic acid (3). We elucidated their chemical structures from the spectral data and compared them with those reported in the literature.3 hợp chất phenolic được phân lập từ cao chiết ethyl acetate của lá thuộc loài Amensiodendron chinese (Merr.) Hu (Sapindaceae) bao gồm : 4-hydroxy-3-methoxybenzaldehyde (1), methyl 3,4-dihydroxybenzoate (2), 3,4-dihydroxybenzoic acid (3). Cấu trúc hóa học được xác định dựa vào dữ liệu phổ và so sánh với tài liệu tham khảo