Stochastic finite element analysis of the free vibration of non-uniform beams with uncertain material

This paper deal with the stochastic finite element method for investigating the eigenvalues of free vibration of non-uniform beams due to a random field of elastic modulus. The formulation of stochastic analysis of the non-uniform beam is established using perturbation method in conjunction with finite element method. Monte Carlo simulation (MCS) used for validation with stochastic finite element approach. The spectral representation was used to generate a random field to employ the Monte Carlo simulation. The performance of results of the uncertain eigenvalue problem of non-uniform beams with random field of elastic modulus by comparing the first-order perturbation technique with the same moments evaluated from the Monte Carlo simulation. The numerical results show that the response of coefficient of variation of eigenvalue increases when the ratio of correlation distance of random field increases

Stochastic finite element analysis of the free vibration of non-uniform beams with uncertain material

This paper deal with the stochastic finite element method for investigating the eigenvalues of free vibration of non-uniform beams due to a random field of elastic modulus. The formulation of stochastic analysis of the non-uniform beam is established using perturbation method in conjunction with finite element method. Monte Carlo simulation (MCS) used for validation with stochastic finite element approach. The spectral representation was used to generate a random field to employ the Monte Carlo simulation. The performance of results of the uncertain eigenvalue problem of non-uniform beams with random field of elastic modulus by comparing the first-order perturbation technique with the same moments evaluated from the Monte Carlo simulation. The numerical results show that the response of coefficient of variation of eigenvalue increases when the ratio of correlation distance of random field increases

Effects of protein levels of commercial diets on the growth performance and survival rate of rabbitfish (Siganus guttatus) at the nursing stage

This study aimed to determine the effect of a commercial diet's protein level on the fry-to-fingerling stage. Thirty days-old fries having the initial length and weight of 18.25 ± 0.15 mm fish-1 and 0.036 ± 0.50 g fish-1 respectively have been used in this study. Diet having three protein levels i.e. 30% (trial 1 as control), 35% (trial 2), 40% (trial 3), and 45% (trial 4), respectively, have been used to evaluate the effect of protein, and each trial has been repeated three times. During the study, stocking density was allocated to 1000 fish per composite tank with a volume of 1 m3. After 30 days of rearing, the weight of fingerlings in trial 1 reached up to 1.50 ± 0.02 g fish-1 and it was recorded as 1.52 ± 0.01g for trial 2, these two were lower than that of trials 3 and 4, where fingerling weight was reported 1.69 ± 0.01 and 1.58g fish-1 respectively and obtained the best weight compared to others. The length of fingerlings at the end of the experimental period was also changed in different trials and it was recorded 47.12; 46.92; 50.97; and 48.89 mm fish-1 for trail 1, 2, 3, and 4 respectively, among the tested combinations lower fingerlings length was recorded for trial 2 (35% CP), but it is not significantly different for trial 1 and 2 and a significant difference (P < 0.05) was reported for trail 2, 3, and 4. The survival rate of fingerlings ranged from 67.27 to 72.33%. Meanwhile, the herd distribution coefficient variation (CVW) in the treatment using 40% protein (trial 3) was the highest at 72.33% (p < 0.05). The results of the study can be concluded that the level of protein has a significant effect on the various growth parameters of fingerlings

ĐA DẠNG THÀNH PHẦN LOÀI CÁ RẠN SAN HÔ Ở VỊNH XUÂN ĐÀI TỈNH PHÚ YÊN

We identified 65 reef fish species belonging to 48 genera, 27 families, 15 orders, and 2 classes (Chondrichthyes and Osteichthyes) at Xuan Dai Gulf, Song Cau town, Phu Yen province. Of these, there are 30 species with high conservation value at different rankings; 26 species with recreational value and used in ornamental fish farming, scuba diving, and recreational fishing; 3 reared species and 4 species likely to be reared; 15 species probably harmful to humans by injuring with fin spines and tail fins.Đã xác định được 65 loài cá rạn san hô thuộc 48 giống, 27 họ, 15 bộ của 2 lớp (cá Sụn – Chondrichthyes và cá xương – Osteichthyes) ở vịnh Xuân Đài, thị xã Sông Cầu, tỉnh Phú Yên. Trong số này, ghi nhận 30 loài có giá trị bảo tồn theo các thứ hạng khác nhau; 26 loài có giá trị giải trí, dùng trong nuôi làm cảnh, lặn ngắm cá và sử dụng trong câu cá thư giãn; 3 loài nuôi và 4 loài có khả năng gây nuôi; 15 loài có thể gây hại cho con người thông qua sát thương bằng gai vây và bằng vây đuôi

ẢNH HƯỞNG CỦA NGUỒN THỨC ĂN ĐẾN SỰ SINH TRƯỞNG CỦA GIUN ĐẤT Amynthas rodericensis (Grube, 1879) TRONG ĐIỀU KIỆN NUÔI THỬ NGHIỆM

Amynthas rodericensis is a common earthworm species in Vietnam. The feeding material and substrate affect the growth and reproduction of earthworms. The individual size, total number, weight, and gain weight of earthworms under laboratory conditions were investigated. The experiment was designed with four treatments (100% pig manure; 75% pig manure and 25% substrate; 50% pig manure and 50% substrate; 25% pig manure and 75% substrate) with six replicates in a completely randomized design; the experiments lasted ten weeks. The maximum growth and reproduction of A. rodericensis are observed with 75% pig manure and 25% substrate.Amynthas rodericensis là loài giun đất phổ biến ở Việt Nam. Nguồn thức ăn và cơ chất là những yếu tố ảnh hưởng đến sự sinh trưởng của giun đất nói chung và A. rodericensis nói riêng. Các yếu tố ảnh hưởng đến sự sinh trưởng bao gồm kích thước, khối lượng cơ thể, số lượng cá thể và tăng trọng cơ thể. Thí nghiệm có bốn nghiệm thức tương ứng với các tỷ lệ phối trộn phân lợn và chất nền khác nhau (NT1: 100% phân lợn; NT2: 75% phân lợn và 25% chất nền; NT3: 50% phân lợn và 50% chất nền; NT4: 25% phân lợn và 75% chất nền); mỗi nghiệm thức lặp lại sáu lần, bố trí theo phương pháp ngẫu nhiên hoàn toàn và được theo dõi đến 10 tuần. Kết quả cho thấy tỷ lệ phối trộn phân lợn với chất nền có ảnh hưởng khác nhau đến khả năng sinh trưởng của giun đất A. rodericensis. Sự sinh trưởng của giun cao nhất ở nghiệm thức NT2 (75% phân lợn và 25% chất nền)

Performance of DASH over Multipath TCP

Recently, dynamic adaptive streaming over HTTP (DASH) is a dominated traffic in Internet. The client requests a suitable representation depending on the current network condition. On the other hand, multipath transmission control protocols emerges as potential data transmission utilizing multiple network paths concurrently. In this paper, we conduct extensively experiments to evaluate the performance of DASH over MPTCP. Four different performance metrics are investigated, i.e., time on high quality, impactful switches, switch frequency, and average bitrate. The results show that the performance of DASH decreases when the paths of MPTCP have different bandwidths

Simple thermal-electrical model of photovoltaic panels with cooler-integrated sun tracker

This paper presents a simple thermal-electrical model of a photovoltaic panel with a cooler-integrated sun tracker. Based on the model and obtained weather data, we analyzed the improved overall efficiency in a year as well as the performance in each typical weather case for photovoltaic panels with fixed-tilt systems with a tilt angle equal to latitude, fixed-tilt systems with cooler, a single-axis sun tracker, and a cooler-integrated single-axis sun tracker. The results show that on a sunny summer day with few clouds, the performance of the photovoltaic panels with the proposed system improved and reached 32.76% compared with the fixed-tilt systems. On a sunny day with clouds in the wet, rainy season, because of the low air temperature and the high wind speed, the photovoltaic panel temperature was lower than the cooler’s initial set temperature; the performance of the photovoltaic panel with the proposed system improved by 12.55% compared with the fixed-tilt system. Simulation results show that, over one year, the overall efficiency of the proposed system markedly improved by 16.35, 13.03, and 3.68% compared with the photovoltaic panel with the fixed-tilt system, the cooler, and the single-axis sun tracker, respectively. The simulation results can serve as a premise for future experimental models

Prescription of antipsychotics and prevalence of metabolic syndrome in Vietnamese inpatients with schizophrenia

Schizophrenia is a severe mental illness, characterized by psychotic symptoms including delusions, hallucinations, dystonia, adolescent behavior and language, and is accompanied by severe functional impairments. Antipsychotics, which are used mainly in the treatment of schizophrenia, have contributed to the development of metabolic syndrome. Studies on metabolic syndrome in schizophrenic patients have been still limited in Vietnam. The objective of this study was to investigate the prevalence of metabolic syndrome in Vietnamese inpatients with schizophrenia. The study population of this descriptive cross-sectional study was all patients with schizophrenia from September 2020 to June 2021 at Inpatient Department of Binh Dinh Provincial Psychiatric Hospital in Viet Nam. Three hundred and twelve patients who met the sampling requirements were enrolled in this study. The prevalence of schizophrenia in female patients was lower than in male patients (36.9% vs. 63.1%) in our study. The prevalence of metabolic syndrome was 30.4% (25.9% in men and 38.3% in women), more in patients ≥40 years old than in patients under 40 years old (the highest prevalence in patients ≥60 years). There was a significant relationship between age, body mass index (BMI), and duration of antipsychotic treatment with the frequency of metabolic syndrome. In conclusions, the prevalence of schizophrenia was higher in male inpatients than in female inpatients. However, the prevalence of metabolic syndrome was higher in female inpatients than male inpatients with schizophrenia, and increased with age, BMI, and duration of antipsychotic treatment

XGV-BERT: Leveraging Contextualized Language Model and Graph Neural Network for Efficient Software Vulnerability Detection

With the advancement of deep learning (DL) in various fields, there are many attempts to reveal software vulnerabilities by data-driven approach. Nonetheless, such existing works lack the effective representation that can retain the non-sequential semantic characteristics and contextual relationship of source code attributes. Hence, in this work, we propose XGV-BERT, a framework that combines the pre-trained CodeBERT model and Graph Neural Network (GCN) to detect software vulnerabilities. By jointly training the CodeBERT and GCN modules within XGV-BERT, the proposed model leverages the advantages of large-scale pre-training, harnessing vast raw data, and transfer learning by learning representations for training data through graph convolution. The research results demonstrate that the XGV-BERT method significantly improves vulnerability detection accuracy compared to two existing methods such as VulDeePecker and SySeVR. For the VulDeePecker dataset, XGV-BERT achieves an impressive F1-score of 97.5%, significantly outperforming VulDeePecker, which achieved an F1-score of 78.3%. Again, with the SySeVR dataset, XGV-BERT achieves an F1-score of 95.5%, surpassing the results of SySeVR with an F1-score of 83.5%