CURRENT SITUATION OF STUDENTS’ PSYCHOLOGICAL STATE BEFORE PRACTICAL COURSES’ FINAL EXAMS

The article aimed to determine the factors influencing students’ psychological state before the final exam of practical courses. The article used conventional scientific research methods in sports and physical training combined with psychological tests studied on fifty students at Ho Chi Minh City University of Physical Education and Sports (UPES). After reviewing related studies and consulting with experts, four tests were employed to assess the psychological state before the test of the research subjects. The results showed that students with a good psychological state to take the exam had good test results. Conversely, students with a feverish or lethargic state will have poor test results. The research results serve as the basis for proposing measures to adjust the psychological state before the exam, contributing to improving the learning results of students.  Article visualizations

A Target Threat Assessment Method for Application in Air Defense Command and Control Systems

Introduction. This paper presents a solution for threat assessment of air targets using the fuzzy logic inference method. The approach is based on the Sugeno fuzzy model, which has multiple inputs representing target trajectory parameters and a single output representing the target threat value. A set of IF–THEN fuzzy inference rules, utilizing the AND operator, is developed to assess the input information.Aim. To develop and test an algorithm model to calculate the threat value of an air target for use in real-time automated command and control systems.Materials and methods. An algorithm model was developed using a fuzzy model to calculate the threat value of a target. The model is presented in the form of a flowchart supported by a detailed stepwise implementation process. The accuracy of the proposed algorithm was evaluated using the available toolkit in MATLAB. Additionally, a BATE software testbed was developed to assess the applicability of the algorithm model in a real-time automated command and control system.Results. The efficiency of the proposed fuzzy model was evaluated by its simulation and testing using MATLAB tools on a set of 10 target trajectories with different parameters. Additionally, the BATE software was utilized to test the model under various air defense scenarios. The proposed fuzzy model was found to be capable of efficiently computing the threat value of each target with respect to the protected object.Conclusion. The proposed fuzzy model can be applied when developing tactical supporting software modules for real-time air defense command and control systems.Introduction. This paper presents a solution for threat assessment of air targets using the fuzzy logic inference method. The approach is based on the Sugeno fuzzy model, which has multiple inputs representing target trajectory parameters and a single output representing the target threat value. A set of IF–THEN fuzzy inference rules, utilizing the AND operator, is developed to assess the input information.Aim. To develop and test an algorithm model to calculate the threat value of an air target for use in real-time automated command and control systems.Materials and methods. An algorithm model was developed using a fuzzy model to calculate the threat value of a target. The model is presented in the form of a flowchart supported by a detailed stepwise implementation process. The accuracy of the proposed algorithm was evaluated using the available toolkit in MATLAB. Additionally, a BATE software testbed was developed to assess the applicability of the algorithm model in a real-time automated command and control system.Results. The efficiency of the proposed fuzzy model was evaluated by its simulation and testing using MATLAB tools on a set of 10 target trajectories with different parameters. Additionally, the BATE software was utilized to test the model under various air defense scenarios. The proposed fuzzy model was found to be capable of efficiently computing the threat value of each target with respect to the protected object.Conclusion. The proposed fuzzy model can be applied when developing tactical supporting software modules for real-time air defense command and control systems

Fabrication of Electrochemical Electrodes Based on Platinum and ZnO\text{ZnO} Nanofibers for Biosensing Applications

Platinum (Pt) electrodes were designed in imitation of screen-printed electrodes, and prepared by microelectronic techniques. These electrodes were then modified with zinc oxide (ZnO) nanofibers for biosensing applications. ZnO nanofibers with average length $\sim 20-30\; \mu$ m and diameter $\sim 150$ nm in hexagonal crystalline structure are prepared using electrospinning method. Their surface characteristics were analyzed by field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction. Electrochemical properties of modified Pt electrodes were investigated in comparison with commercial carbon screen-printed electrodes. The results showed that the cyclic voltammogram of modified Pt electrodes was stable, but has much lower resistance compared to that of carbon screen-printed electrodes

Метод обработки данных в комплексе прибрежных РЛС средней дальности

The article presents the basic principles of design and development of integrated middle range Coastal Surveillance System (CSS) used for water surface lookout. It provides solutions for such missions as command and control of maritime forces, border monitoring and control, prevention of illegal activities such as piracy, smuggling, illegal immigration, illegal fishing, supporting search and rescue (SAR) operations, and creates a common situation awareness picture of the Naval Theatre. The system structure diagram is designed to solve computational overload problem when processing large volume of data received from radar stations. The measurement-level fusion algorithm is developed based on the JPDA framework, in which radar data received from a single or group of radars and AIS data is aggregated in a processing center. The servers and workstations make use of local area network (LAN), using standard Gigabit Ethernet technologies for local network communications. Acquisition, analysis, storage and distribution of target data is executed in servers, then the data is sent to automated operator stations (console), where functional operations for managing, identifying and displaying of target on digital situational map are performed.Представлены основные принципы проектирования и построения интегрированной системы прибрежных РЛС средней дальности для наблюдения за надводной обстановкой в акваториях с интенсивным движением малых судов. Система предоставляет решения для таких целей, как командование и контроль над морскими силами, пограничный мониторинг и контроль, предотвращение незаконной деятельности (пиратства, контрабанды, незаконной иммиграции, незаконного промысла), поддержки операций по поиску и спасению и т. д. Комплекс прибрежного наблюдения должен интегрировать данные нескольких радаров SCORE 3000 и сообщения от автоматической идентификационной системы (АИС) и обеспечивать корреляцию данных этих систем. Разработана структурная схема системы, обеспечивающая распределение вычислительной нагрузки при обработке большого объема данных, поступающих от РЛС. Предложен алгоритм на основе структуры Joint Probabilistic Data Association (JPDA) для объединения радиолокационных данных от одной или нескольких РЛС и данных АИС, поступающих в центр обработки информации. Сбор, хранение, анализ и распределение данных осуществляются на компьютерном сервере, функции управления, идентификации и отображения целей на цифровой карте реализуются на автоматизированном рабочем месте

Синтез алгоритма траекторной обработки объектов методами теории кластеризации данных

Introduction.  Requirements for the quality of information about the trajectory of moving objects provided by sensor networks are increasingly becoming more stringent. For Information and Data Processing Centers (DPC) at control and management command posts, the issue of information mapping and forming the true trajectories of moving objects in the area of intersection of network detection zones is of particular importance. The use of conventional approaches to solving this problem involves issues  related to ensuring the efficient provision of users with complete and reliable information about trajectories in real time. In this article, wee propose a new approach to solving this problem using data mining theory, in particular, the methods of data clustering theory. Based on an analysis of the process of processing radar data in a DPC and its similarity with that of data clustering, we synthesized an algorithm for processing the trajectories of moving objects. The algorithm was verified by modelling and experimental research.Aim.  To develop a generalized scheme for processing object trajectories (TP) in a DPC and to synthesized a TP algorithm using the methods of data clustering theory.Materials  and  methods.  Data  Clustering  theory,  Systems   Engineering  theory,  Radar  Data  processing  theory (RD), methods of mathematical modelling and experimental research.Results.  Based on an analysis of the essence of radar data processing (RD) in a DPC and its similarity with the process of data clustering,  an algorithm for processing the trajectories of moving objects was synthesized and verified by modelling and experimental research. A generalized scheme for processing the trajectories of moving objects in a DPC and a TP algorithm for a DPC were synthesized.Conclusions.  An algorithm for processing object trajectories was proposed based on a new approach of data clustering theory. A generalized scheme and an algorithm for processing object trajectories (TP) in a DPC were suggested. These developments can be  effectively applied in various models, e.g. centralized, hierarchical and decentralized. The synthesized algorithm can provide output information about the true identified trajectories in terms of various indicators of data processing systems (DPS).Введение.  С  каждым  годом  становится  сложнее  совершенствовать  процесс  обработки  информации  о траекториях движения объектов, получаемой  из сенсорной сети. Этот процесс имеет особое значение для  центров обработки информации и данных (ЦОИД), в которых осуществляется контроль и управление, так как возникает вопрос сопоставления информации и формирования истинных траекторий объектов в области пересечения зон обнаружения сети. При использовании традиционных подходов  к  решению  данной  проблемы  возникают  вопросы,  связанные  с  обеспечением  эффективного  предоставления  пользователем  выходной  достоверной  траекторной  информации  в  реальном  времени.  В  данной статье предложен новый подход к решению этого вопроса на основе теории интеллектуального анализа данных (data mining) с помощью методов кластеризации данных.Цель работы. Разработка обобщенной схемы траекторной обработки (ТО) в ЦОИД и синтез алгоритма ТО с использованием методов кластеризации данных.Материалы и методы.  Теория кластеризации данных, теория системотехники,  теория обработки радиолокационной  информации  (РЛИ), методы математического моделирования и практического исследования.Результаты.  На основе анализа сущности процесса обработки  РЛИ  в ЦОИД и его сходства с процессом кластеризации  данных  синтезирован  алгоритм  траекторной  обработки  объектов,  проверенный  моделированием  и  экспериментально.  Помимо  алгоритма  синтезирована  структурная  схема  ТО  для  ЦОИД, полученной из сенсорной сети.Заключение.  Предложены обобщенная  структурная  схема  и  алгоритм  ТО  для  ЦОИД.  Они  могут  эффективно применяться для различных системных моделей ТО, таких, как  централизованная, иерархическая и децентрализованная.  Синтезированный  алгоритм  может  обеспечивать  предоставление  выходных данных об  истинных отождествленных траекториях по многим показателям системы обработки информации (СОИ)

A High-Quality Genome Assembly of Striped Catfish (Pangasianodon hypophthalmus) Based on Highly Accurate Long-Read HiFi Sequencing Data

The HiFi sequencing technology yields highly accurate long-read data with accuracies greater than 99.9% that can be used to improve results for complex applications such as genome assembly. Our study presents a high-quality chromosome-scale genome assembly of striped catfish (Pangasianodon hypophthalmus), a commercially important species cultured mainly in Vietnam, integrating HiFi reads and Hi-C data. A 788.4 Mb genome containing 381 scaffolds with an N50 length of 21.8 Mb has been obtained from HiFi reads. These scaffolds have been further ordered and clustered into 30 chromosome groups, ranging from 1.4 to 57.6 Mb, based on Hi-C data. The present updated assembly has a contig N50 of 14.7 Mb, representing a 245-fold and 4.2-fold improvement over the previous Illumina and Illumina-Nanopore-Hi-C based version, respectively. In addition, the proportion of repeat elements and BUSCO genes identified in our genome is remarkably higher than in the two previously released striped catfish genomes. These results highlight the power of using HiFi reads to assemble the highly repetitive regions and to improve the quality of genome assembly. The updated, high-quality genome assembled in this work will provide a valuable genomic resource for future population genetics, conservation biology and selective breeding studies of striped catfish

Синтез обобщенного алгоритма обработки и формирования данных по отраженным сигналам от сложных целей

Introduction. The quality of input information for trajectory processing (TP) systems can be improved by increasing the measurement accuracy of radar sensors (RS). However, in such a case, radar targets acquire the characteristics of complex targets having several marks at the output of the detector. This makes it difficult to accurately assess the kinetic parameters of targets in a TP system. In this respect, the development of a generalized algorithm for processing and generating data from the reflected signals of complex targets seems a relevant research task.Aim. To investigate reasons for the formation of complex targets and, using the theory of radar image processing, to synthesize an algorithm for processing and generating data on reflected signals from a complex target.Materials and methods. The following methodological approaches were used: the theory of digital signal processing; applied theory of radar image processing; MATLAB Simulink Toolboxes for simulating radar image processing; some prerequisites for fuzzy clustering methods.Results. Following an analysis of some characteristics of complex targets and the theory of radar image processing, an generalized algorithm was synthesized for processing and generating data of reflected signals from this class of targets. The results can be used to improve the measurement accuracy of their representative point when solving the TP problem.Conclusion. Reasons for the formation of complex targets in radar technology were analyzed. Their specific features consist in the need to accurately assess a true mark. A generalized algorithm for processing and generating these signals reflected from complex targets was proposed. The results can serve as a basis for solving the TP problem.Введение. Повышение качества входной информации для системы траекторной обработки (ТО) на основе повышения точности измерений радиолокационных (РЛ) сенсоров является одним из очевидных подходов. Однако при этом РЛ-цели могут стать "сложными целями", имеющими несколько отметок на выходе обнаружителя. Это затрудняет точную оценку кинетических параметров целей в системе ТО. В статье представлены результаты синтеза обобщенного алгоритма обработки и формирования данных из отраженных сигналов сложных целей, позволяющего точно оценить кинетические параметры для решения задачи ТО.Цель работы. Краткое изучение причин формирования "сложных целей". Синтез обобщенного алгоритма обработки и формирования данных по отраженным сигналам от сложных целей на основе теории обработки РЛ-изображений.Материалы и методы. Теория цифровой обработки сигналов; прикладная теория обработки РЛ-изображений; MATLAB Simulink Toolboxes для моделирования обработки РЛ-изображений; методы нечеткой кластеризации.Результаты. На основе анализа некоторых характеристик сложных целей и теории обработки РЛ-изображений синтезирован обобщенный алгоритм обработки и формирования данных отраженных сигналов от этого класса целей, являющихся предпосылкой для точной оценки их "представительной отметки" при решении задачи ТО.Заключение. В статье проведен анализ особенностей формирования сложных целей в РЛ-технике и их особенностей при точной оценке истинной отметки; синтезирован обобщенный алгоритм обработки и формирования РЛ-сигналов, отраженных от сложных целей, являющийся основой при решении задач ТО

Selective breeding of saline-tolerant striped catfish (Pangasianodon hypophthalmus) for sustainable catfish farming in climate vulnerable Mekong Delta, Vietnam

peer reviewedStriped catfish (Pangasianodon hypophthalmus), a freshwater species cultured mainly in the Mekong Delta region in Southern Vietnam, is facing a significant challenge due to salinity intrusion as a result of climatic changes. Given these evolving environmental conditions, selecting new strains with a higher salinity tolerance could make production of striped catfish economically feasible in brackish environments. In this study, we carried out a selection program aimed at developing a striped catfish strain able to survive and grow fast in a saline environment. To implement the selection program, we first collected males and females from different provinces in the Mekong delta. We next performed a factorial cross of these breeders to produce half- and full-sib families. When fish reached fry stage (47 dph), we put them in a saline environment (10 ppt) and subsequently kept 50 % of the fastest-growing fish after 143 days post hatching (dph). We repeated this mass selection procedure after 237 dph and 340 dph. We maintained in parallel a randomly selected group in saline conditions and a group of fish reared in freshwater to serve as controls. After crossing the selected individuals, we performed several tests on the next generation of fish to evaluate the effectiveness of selection after one generation in saline conditions. Average direct responses to selection were 18.0 % for growth and 11.4 % for survival rate after one generation of selection. We estimated a moderate realized heritability (0.29) for body weight. The genetic gains obtained in our study for body weight and survival rate after one generation of selection under saline conditions suggest that selection can be effective to improve ability of striped catfish to cope with saline stress. We conclude that our selection program has succeeded in developing a productive strain of striped catfish with better tolerance to salinity. © 2022 The Author

Farming systems in the sandy area of the Thua Thien Hue Province, Central Vietnam, survey of socio-economic situation and constraints identified by farmers

peer reviewe

THÀNH PHẦN HÓA HỌC VÀ HOẠT TÍNH CHỐNG OXY HÓA CỦA CÁC DỊCH CHIẾT TỪ HOA XUYẾN CHI (Bidens pilosa)

Bidens pilosa is used in traditional medicine in Vietnam. The antioxidant potential of the ethanol extract and fractions from the flowers of Bidens pilosa was evaluated through DPPH and ABTS radical scavenging and the total antioxidant capacity method. The ethyl acetate fraction exhibits the highest activity with the lowest IC50 value (IC50 = 31.54 μg·mL–1 and IC50 = 35.33 μg·mL–1 for DPPH and ABTS radical scavenging capacity), and the total antioxidant capacity was 85.05 ± 0.28 mg GA·g–1. The composition of Bidens pilosa flowers: the total phenolic, total flavonoid, polysaccharides, and triterpenoid, was examined by using the colorimetric method, and their quantities are equivalent to 59.35 ± 0.83 mg GAE·g–1, 42.35 ± 1.50 mg QE·g–1, 4.44 ± 0.02%, and 32.88 ± 0.66 mg acid oleanolic·g–1, respectively. Specifically, the polysaccharide and total triterpenoid content of Bidens pilosa flowers was reported for the first time.Xuyến chi đã được sử dụng trong các bài thuốc cổ truyền Việt Nam. Khả năng chống oxy hóa của cao toàn phần và các cao phân đoạn từ hoa cây Xuyến chi được đánh giá thông qua ba mô hình: tổng khả năng chống oxy hoá, khả năng bắt gốc tự do DPPH và khả năng bắt gốc ABTS. Kết quả cho thấy cao ethyl acetate có khả năng chống oxy hóa tốt nhất với IC50 nhỏ nhất (IC50 = 31,54 μg·mL–1 và           IC50 = 35,33 μg·mL–1 tương ứng với khả năng bắt gốc DPPH và ABTS) và hàm lượng các chất chống oxy hóa cao nhất (85,05 ± 0,28 mg·g–1 acid gallic). Hàm lượng các hợp chất có hoạt tính sinh học (tổng các hợp chất phenol, tổng flavonoid, tổng triterpenoid và polysaccharide) trong dịch chiết hoa cây Xuyến chi được xác định bằng phương pháp trắc quang. Hàm lượng tổng các hợp chất phenol và flavonoid là 59,35 ± 0,83 mg GAE·g–1 và 42,35 ± 1,50 mg QE·g–1; hàm lượng polysacharide và triterpenoid là 4,44 ± 0,02% và 32,88 ± 0,66 mg acid oleanolic·g–1. Lần đầu tiên, tổng hàm lượng triterpenoid và polysacharide trong hoa Xuyến chi được công bố