Static analysis of 2D-FG nonlocal porous tube using gradient strain theory and based on the first and higher-order beam theory

Xiaozhong Zhang,Jian-Feng Li,Yan Cui,Mostafa Habibi,H. Elhosiny Ali,Ibrahim AlBaijan,Tayebeh Mahmoudi 국제구조공학회 2023 Steel and Composite Structures, An International J Vol.49 No.3

This article focuses on the study of the buckling behavior of two-dimensional functionally graded (2D-FG) nanosize tubes, including porosity, based on the first shear deformation and higher-order theory of the tube. The nano-scale tube is simulated using the nonlocal gradient strain theory, and the general equations and boundary conditions are derived using Hamilton’s principle for the Zhang-Fu’s tube model (as a higher-order theory) and Timoshenko beam theory. Finally, the derived equations are solved using a numerical method for both simply-supported and clamped boundary conditions. A parametric study is performed to investigate the effects of different parameters, such as axial and radial FG power indices, porosity parameter, and nonlocal gradient strain parameters, on the buckling behavior of the bi-dimensional functionally graded porous tube. Keywords: Nonlocal strain gradient theory; buckling; Zhang-Fu’s tube model; Timoshenko theory; Two-dimensional functionally graded materials; Nanotubes; Higher-order theory.

Off-grid direction-of-arrival estimation for wideband noncircular sources

Xiaoyu Zhang1,Haihong Tao,Ziye Fang,Jian Xie 한국전자통신연구원 2023 ETRI Journal Vol.45 No.3

Researchers have recently shown an increased interest in estimating the direction-of-arrival (DOA) of wideband noncircular sources, but existing studies have been restricted to subspace-based methods. An off-grid sparse recovery-based algorithm is proposed in this paper to improve the accuracy of existing algorithms in low signal-to-noise ratio situations. The covariance and pseudo covariance matrices can be jointly represented subject to block sparsity constraints by taking advantage of the joint sparsity between signal components and bias. Furthermore, the estimation problem is transformed into a single measurement vector problem utilizing the focused operation, resulting in a significant reduction in computational complexity. The proposed algorithm's error threshold and the Cramer–Rao bound for wideband noncircular DOA estimation are deduced in detail. The proposed algorithm's effectiveness and feasibility are demonstrated by simulation results.

A New ent-Kaurane type Diterpenoid Glycoside from Inula japonica Thunb

Jiang Jiang Qin,Jia Xian Zhu,Wei Dong Zhang1,2,Yan Zhu,Jian Jun Fu,Xiao Hua Liu,Hui Zi Jin 대한약학회 2009 Archives of Pharmacal Research Vol.32 No.10

A new ent-kaurane type diterpenoid glycoside, 17-O-β-D-glucopyranosyl-16α-ent-kauran-19-oic acid (1), together with 17-hydroxy-16α-ent-kauran-19-oic acid (2), 16α,17-dihydroxyl-ent-kauran-19-oic acid (3), and 16α-hydroxy-17-acetoxy-ent- kauran-19-oic acid (4) were isolated from the aerial parts of Inula japonica Thunb. The structure of 1 was determined mainly by use of 1D and 2D NMR spectroscopic techniques including HSQC, 1H-1H COSY, HMBC, and NOESY. In addition, 4 exhibited significant inhibitory activity on NO production in LPS-stimulated RAW264.7 cells with IC50 value of 14.3 μg/mL.

Carbon dispersed iron-manganese catalyst for light olefin synthesis from CO hydrogenation

Jianli Zhang,Kegong Fang,Kan Zhang,Wenhuai Li,Yuhan Sun 한국화학공학회 2009 Korean Journal of Chemical Engineering Vol.26 No.3

High performance iron-manganese catalysts dispersed with carbon to produce light olefins from CO hydrogenation were prepared by sol-gel method using citric acid as precursor. The effects of carbon content on the bulk structure, the water gas shift reaction, the chain propagation ability and the activity and selectivity of the catalysts were investigated. The results showed that the catalysts were gradually reduced during the decomposition of the precursor when calcined under pure N2. The formation of iron-manganese mixed crystallites was favored and stabilized because of the enhanced interaction of iron and manganese with increasing carbon content. During the subsequent CO hydrogenation reaction, all the catalysts showed high activity and olefin selectivity. With increasing carbon content, the water gas shift (WGS) reaction was restrained and the chain propagation ability was inhibited. Catalysts with higher carbon content showed much lighter hydrocarbon products; however, the selectivity of CH4 was almost unchanged.

Optimal layout of long-gauge sensors for deformation distribution identification

Jian Zhang,Qingqing Zhang,Qi Xia,Zhishen Wu 국제구조공학회 2016 Smart Structures and Systems, An International Jou Vol.18 No.3

Structural deflection can be identified from measured strains from long gague sensors, but the sensor layout scheme greatly influences on the accuracy of identified resutls. To determine the optimal sensor layout scheme for accurate deflection identification of the tied arch bridge, the method of optimal layout of long-gauge fiber optic sensors is studied, in which the characteristic curve is first developed by using the bending macro-strain curve under multiple target load conditions, then optimal sensor layout scheme with different number of sensors are determined. A tied arch bridge is studied as an example to verify the effectiveness and robustness of the proposed method for static and dynamic deflection identification.

Supplementation of guanidinoacetic acid and rumen-protected methionine increased growth performance and meat quality of Tan lambs

Zhang Jian Hao,Li Hai Hai,Zhang Gui Jie,Zhang Ying Hui,Liu Bo,Huang Shuai,Guyader Jessie,Zhong Rong Zhen 아세아·태평양축산학회 2022 Animal Bioscience Vol.35 No.10

Objective: Tan lambs (n = 36, 3 mo old, 19.1±0.53 kg) were used to assess effects of dietary guanidinoacetic acid (GAA) and rumen-protected methionine (RPM) on growth performance, carcass traits, meat quality, and serum parameters. Methods: Lambs were randomly assigned to three treatment groups, with 6 pens per group and 2 lambs per pen. Dietary treatments were: basal diet alone (I); basal diet supplemented with 0.08% GAA+0.06% RPM (II); and basal diet supplemented with 0.08% GAA+0.08% RPM (III). Diets were provided three times a day for 90 d. Intake per pen was recorded daily and individual lamb body weight (BW) was measured monthly. Carcass traits were measured after slaughter and meat quality at the end of the experiment, blood samples were taken on a subgroup of lambs for analysis of indicators mostly related to protein metabolism. Results: Final BW and average daily gain for the first and second month, and for the entire experiment were greater in Treatment II compared to Treatment I (p<0.05), whereas feed to gain ratio was lower (p<0.05). Treatment II had the optimal dressing percentage and net meat weight proportion, as well as crude protein and intramuscular fat concentrations in muscles. Treatment II improved meat quality, as indicated by the greater water holding capacity, pH after 45 min and 48 h, and lower shear force and cooking loss. Dietary supplementation of GAA and RPM also increased the meat color a* and b* values at 24 h. Finally, Treatment II increased total protein, and serum concentrations of albumin and creatinine, but decreased serum urea nitrogen concentrations, indicating improved protein efficiency. Conclusion: In this study, 0.08% GAA+0.06% RPM supplementation improved growth performance and meat quality of Tan lambs. Objective: Tan lambs (n = 36, 3 mo old, 19.1±0.53 kg) were used to assess effects of dietary guanidinoacetic acid (GAA) and rumen-protected methionine (RPM) on growth performance, carcass traits, meat quality, and serum parameters.Methods: Lambs were randomly assigned to three treatment groups, with 6 pens per group and 2 lambs per pen. Dietary treatments were: basal diet alone (I); basal diet supplemented with 0.08% GAA+0.06% RPM (II); and basal diet supplemented with 0.08% GAA+0.08% RPM (III). Diets were provided three times a day for 90 d. Intake per pen was recorded daily and individual lamb body weight (BW) was measured monthly. Carcass traits were measured after slaughter and meat quality at the end of the experiment, blood samples were taken on a subgroup of lambs for analysis of indicators mostly related to protein metabolism.Results: Final BW and average daily gain for the first and second month, and for the entire experiment were greater in Treatment II compared to Treatment I (p<0.05), whereas feed to gain ratio was lower (p<0.05). Treatment II had the optimal dressing percentage and net meat weight proportion, as well as crude protein and intramuscular fat concentrations in muscles. Treatment II improved meat quality, as indicated by the greater water holding capacity, pH after 45 min and 48 h, and lower shear force and cooking loss. Dietary supplementation of GAA and RPM also increased the meat color a* and b* values at 24 h. Finally, Treatment II increased total protein, and serum concentrations of albumin and creatinine, but decreased serum urea nitrogen concentrations, indicating improved protein efficiency.Conclusion: In this study, 0.08% GAA+0.06% RPM supplementation improved growth performance and meat quality of Tan lambs.

Effect of Different Levels of Nitrogen, Phosphorus, and Potassium on Root Activity and Chlorophyll Content in Leaves of Brassica oleracea Seedlings Grown in Vegetable Nursery Substrate

Jian Zhang,Yan Wang,Pengcheng Wang,Qi an Zhang,Congsheng Yan,Feifei Yu,Jianqun Yi,Ling Fang 한국원예학회 2017 Horticulture, Environment, and Biotechnology Vol.58 No.1

Nutrients in the substrate are important for plant growth, particularly during the development of vegetableseedlings. The continued development of intensive methods to produce seedlings has made growing healthy and high-gradeseedlings a requirement for nurseries. This study evaluated the effect of nitrogen (N), phosphorus (P), and potassium(K) on the root activity, dry weight, and chlorophyll content in leaves of Brassica oleracea seedlings. D-optimal designwas used in this study because of its accuracy. A total of 10 treatments (T1–T10) were designed, and differentconcentrations were chosen in the following ranges: N (0.6-5.0 g·kg-1), P (0.2-6.0 g·kg-1), and K (0.7-7.0 g·kg-1). Our studyshows that the application of N, P, and K to the substrate significantly influenced the growth of B. oleracea seedlings. T6significantly increased root activity, root dry weight, chlorophyll content in leaves when compared with the control T1,which had added nutrient concentrations at normal levels. However, the addition of high levels of N (5.0 g·kg-1) withhigh (7.0 g·kg-1) or low (0.7 g·kg-1) levels of K (T2 and T9) not only significantly decreased the root dry weight but alsodecreased leaf area. Our results suggest that N, P, and K can be added to the substrate at an appropriate ratio togrow vigorous B. oleracea seedlings under intensive seedling production conditions. The present results give insightinto the nutrient requirements during early growth of B. oleracea seedlings in growth substrate.

Energy-Efficient Adaptive Dynamic Sensor Scheduling for Target Monitoring in Wireless Sensor Networks

Jian Zhang,Cheng-dong Wu,Yun-zhou Zhang,Peng Ji 한국전자통신연구원 2011 ETRI Journal Vol.33 No.6

Due to uncertainties in target motion and randomness of deployed sensor nodes, the problem of imbalance of energy consumption arises from sensor scheduling. This paper presents an energy-efficient adaptive sensor scheduling for a target monitoring algorithm in a local monitoring region of wireless sensor networks. Owing to excessive scheduling of an individual node, one node with a high value generated by a decision function is preferentially selected as a tasking node to balance the local energy consumption of a dynamic clustering, and the node with the highest value is chosen as the cluster head. Others with lower ones are in reserve. In addition, an optimization problem is derived to satisfy the problem of sensor scheduling subject to the joint detection probability for tasking sensors. Particles of the target in particle filter algorithm are resampled for a higher tracking accuracy. Simulation results show this algorithm can improve the required tracking accuracy, and nodes are efficiently scheduled. Hence, there is a 41.67% savings in energy consumption.

Discrete Poisson Noise Logging Image Repair Based on Schatten Matrix Operator

Zhang Jian,Yang Jie,Zhang bin 보안공학연구지원센터 2016 International Journal of Multimedia and Ubiquitous Vol.11 No.3

In order to solve the problem that the present logging image reconstruction algorithm has certain staircase effect and ring effect during the discrete Poisson noise image repair process, a noise reduction algorithm based on Schatten matrix operator for discrete Poisson logging image is proposed in this article. Specifically, Schatten norm matrix of Hessian operator is adopted to estimate each pixel value of the image, and meanwhile the non-quadratic regularization function is adopted to eliminate the staircase effect; then Poisson measurement model is integrated with Schatten regularization function to construct the minimum objective function; then norm proximal mapping estimation algorithm is defined and is adopted to decouple the data fidelity item and the regularization matrix in the objective function, thus to recover the image. The simulation result shows: compared with present denoising technology, the algorithm proposed in this article has better repair effect and greater similarity in the aspect of processing the discrete Poisson noise.

Preparation, self-assembly and performance modulation of gold nanoparticles decorated ferrocene-containing hybrid block copolymer multifunctional materials

Jian-Guo Zhang,Xue-Yin Zhang,Hua Yu,Yan-Ling Luo,Feng Xu,Ya-Shao Chen 한국공업화학회 2018 Journal of Industrial and Engineering Chemistry Vol.65 No.-

Gold nanoparticles decorated stimuli-responsive copolymer hybrids, poly(2-methacryloyloxyethyl ferrocenecarboxylate)-block-poly(N-isopropylacryamide) decorated with gold nanoparticles, were synthesized through two-step successive RAFT and ensuing in-situ reduction. The hybrids could self-assemble into interesting micelle structures from globular, wormlike to rodlike shapes by altering the quality and compositions of solvents and ionic strength, and exhibited multifunctionality including quasi-reversible electrochemical behavior, redox-stress responsiveness and temperature sensitivity. The physicochemical and electrochemical properties were modulated by tailor-making the system compositions and redox reaction. The copolymer hybrids were expected to broaden their applications in nanobiomedicine including targeted drug carriers and magnetic resonance imaging, optical, electrochemical catalyst, optoelectronics and sensors etc.