Inhomogeneity Image Segmentation with Optimal Spatial Scale

Xiaozhen Xie,Xiaoning Hu,Bo Yang 보안공학연구지원센터 2016 International Journal of Signal Processing, Image Vol.9 No.11

A novel local region-based active contour model is proposed to segment medical images with intensity inhomogeneities and various noises. The contribution of the proposed work is twofold. First, the anisotropy of evolution contours is exploited to characterize the local classification information around each pixel. Integrating it with local gray intensity information, the new model stabilizes the active contours in all evolving processes. Second, under the constraint of maximum absolute error of parameter estimation, the optimal spatial scales are automatically selected for the local segmentation models. It is demonstrated from the experiments that our algorithm achieves faster and more robust results than several same-type methods.

Aerodynamic Interference and Dynamic Influence of Wind Barrier on Train-bridge Coupling Vibration System

Xiaozhen Li,Yanxi Zhou,Ming Wang 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.7

Wind barrier is an important wind-resistant measure for the running performance of trains on long-span bridges. This study aims to clarify how the aerodynamic interference of wind barrier to the train-bridge system affects the dynamic response of the system. The aerodynamic interference and dynamic influence of wind barriers on the train-bridge system are studied by wind tunnel test and coupling vibration analysis. Wind barriers with different ventilation rates are selected to study their wind-resistant performance on trains travelling in four lanes on the bridge. The results show that installing wind barriers can increase the side and lift coefficients of bridge and decrease the side and lift coefficients of train. The maximum difference is that installing a wind barrier with ventilation of 0 can increase the side coefficient of the bridge by 0.6, while reducing the side coefficient of train in Lane 1 from 1.25 to -0.25. Although the wind barrier has changed the aerodynamic coefficient of the bridge, the maximum dynamic response of train-bridge system depends more on its influence on the aerodynamic coefficient of train. Installing a wind barrier with 0% ventilation rate can reduce the maximum lateral displacement at mid span of bridge by 10 mm, the maximum reduction rate of the wheel from 0.38 to 0.1, and the lateral car body acceleration from 1.1 m/s2 to 0.45 m/s2. The vertical dynamic response of train-bridge system is insensitive to wind barrier. The key effect of optimizing train side coefficient on wind-resistant performance of wind barrier is pointed out.

Temporal dynamics of Bactrocera (Zeugodacus) tau (Diptera: Tephritidae) adults in north Jiangxi, a subtropical area of China revealed by eight years of trapping with cuelure

Xiaozhen Li,Haiyan Yang,Kaiping Hu,Jianguo Wang 한국응용곤충학회 2020 Journal of Asia-Pacific Entomology Vol.23 No.1

Bactrocera (Zeugodacus) tau (Walker) (Diptera: Tephritidae), a quarantine pest of international concern, has become widespread and economically important in South and Southeast Asia. It has been introduced into north Jiangxi from Fujian, China and become a threat to local fruits and vegetables. Field trapping with cuelure (CUE) as lure is needed, not only for monitoring population dynamics of B. tau but also for direct control of population. In this study, we collected weekly tephritids from 4 CUE-baited McPhail traps every year from 2008 to 2015, analysing seasonal and inter-year B. tau population fluctuations. The total number of captured tephritids reached 7811, including B. tau (5321), B. scutellata (Hendel) (2375) and B. cucurbitae (Coquillett) (1 1 5). Among them, B. tau was the dominant species. It had 3–4 generations a year in north Jiangxi with high generation overlapping. The average number of trapped B. tau males did not differ significantly in different years, while the average monthly number showed large variation from June to December. No B. tau males were trapped before June in any year. Adult males were present from mid-June to late December, with distinct peaks between late August and mid-October. This fruit fly can withstand below 13℃ as a monthly minimal temperature under field conditions, and adult capture rates were significantly related to monthly minimal temperature and monthly total precipitation. These results can be used to predict the occurrence time and population size of B. tau in different seasons, enabling growers and extension personnel to take efficient management measures before they damage the host crops.

High performance proton-conducting solid oxide fuel cells with a layered perovskite GdBaCuCoO5+x cathode

Xiaozhen Zhang,Yuhua Jiang,Xuebing Hu,Liangliang Sun,Yihan Ling 대한금속·재료학회 2018 ELECTRONIC MATERIALS LETTERS Vol.14 No.2

Proton-conducting solid oxide fuel cell (H-SOFC) based on layered perovskite type GdBaCuCoO5+x (GBCC) cathodewas fabricated with in situ drop-coating BaZr0.1Ce0.7Y0.2O3−δ (BZCY) electrolyte membrane. The influences of Cu dopinginto Co sites of GdBaCo2O5+x on the electrical conductivity and conduction mechanism, thermal expansion propertyand electrochemical performance of cathode materials and corresponding single cell were investigated. Results show thatthe electrical conductivity decreased and the conduction mechanism would gradually transform to the semiconductor-likebehavior. A high maximum power density of 480 mW cm−2 was obtained for the anode supported NiO–BZCY/NiO–BZCY/BZCY/GBCC single cells with wet H2fuel at 700 °C. The corresponding polarization resistance was as low as 0.17 Ω cm2. The excellent electrochemical performance of as-prepared single cell indicates that GBCC is a good candidate of cathodematerials for H-SOFCs.

Deregulation of DNA Damage Signal Transduction by Herpesvirus Latency-Associated M2

Liang, Xiaozhen,Pickering, Mary T.,Cho, Nam-Hyuk,Chang, Heesoon,Volkert, Michael R.,Kowalik, Timothy F.,Jung, Jae U. American Society for Microbiology 2006 Journal of virology Vol.80 No.12

<B>ABSTRACT</B><P>Infected cells recognize viral replication as a DNA damage stress and elicit a DNA damage response that ultimately induces apoptosis as part of host immune surveillance. Here, we demonstrate a novel mechanism where the murine gamma herpesvirus 68 (γHV68) latency-associated, anti-interferon M2 protein inhibits DNA damage-induced apoptosis by interacting with the DDB1/COP9/cullin repair complex and the ATM DNA damage signal transducer. M2 expression constitutively induced DDB1 nuclear localization and ATM kinase activation in the absence of DNA damage. Activated ATM subsequently induced Chk activation and p53 phosphorylation and stabilization without eliciting H2AX phosphorylation and MRN recruitment to foci upon DNA damage. Consequently, M2 expression inhibited DNA repair, rendered cells resistant to DNA damage-induced apoptosis, and induced a G1 cell cycle arrest. Our results suggest that γHV68 M2 blocks apoptosis-mediated intracellular innate immunity, which might ultimately contribute to its role in latent infection.</P>

Chinese Medicine Granule Affects the Absorption and Transport of Glucose in Porcine Small Intestinal Brush Border Membrane Vesicles under Heat Stress

Song, Xiaozhen,Xu, Jianqin,Wang, Tian,Liu, Fenghua Asian Australasian Association of Animal Productio 2009 Animal Bioscience Vol.22 No.2

This study was conducted to investigate the effects of Chinese medicine granule (CMG, including Cortex Phellodendron, Atractylodes Rhizome, Agastache Rugosa and Gypsum Fibrosum) on absorption and transport of glucose in porcine small intestinal brush border membrane vesicles (BBMVs) under heat stress. Forty-eight 2-month-old Chinese experimental barrows were screened according to weight and litter origin, and then allotted to three groups and treated as follows: Normal temperature control group (NTCG; $23^{\circ}C$), high temperature control group (HTCG; $26^{\circ}C$ for 19 h, $40^{\circ}C$ for 5 h); Chinese medicine granule anti-stress group (CMGG; $26^{\circ}C$ for 19 h, $40^{\circ}C$ for 5 h) (n = 16 per group). The results showed that high temperature treatment decreased (p<0.05) the growth performance and intestinal glucose absorption but there was no change (p>0.05) in the expression of SGLT1 and GLUT2 genes in the small intestine of pigs compared with the NTCG. Dietary supplementation with CMG improved the growth performance, and increased the activity of disaccharidases in duodenum and jejunum of heat stressed pigs (p<0.05). CMG treatment increased (p<0.05) the protein levels of SGLT1 and GLUT2 in the small intestine, and up-regulated (p<0.05) the expression of SGLT1 and GLUT2 genes in the duodenum and jejunum but without changing (p>0.05) them in the ileum compared with the HTCG. These results indicated that CMG treatment significantly improved porcine growth performance, and increased intestinal glucose absorption and transport by BBMVs under heat stress, in addition to up-regulating the expression of SGLT1 and GLUT2 genes in porcine duodenum and jejunum.

Stochastic space vibration analysis of a train-bridge coupling system

Li, Xiaozhen,Zhu, Yan Techno-Press 2010 Interaction and multiscale mechanics Vol.3 No.4

The Pseudo-Excitation Method (PEM) is applied to study the stochastic space vibration responses of train-bridge coupling system. Each vehicle is modeled as a four-wheel mass-spring-damper system with two layers of suspension system possessing 15 degrees-of- freedom. The bridge is modeled as a spatial beam element, and the track irregularity is assumed to be a uniform random process. The motion equations of the vehicle system are established based on the d'Alembertian principle, and the motion equations of the bridge system are established based on the Hamilton variational principle. Separate iteration is applied in the solution of equations. Comparisons with the Monte Carlo simulations show the effectiveness and satisfactory accuracy of the proposed method. The PSD of the 3-span simply-supported girder bridge responses, vehicle responses and wheel/rail forces are obtained. Based on the $3{\sigma}$ rule for Gaussian stochastic processes, the maximum responses of the coupling system are suggested.

Traditional Chinese Medicine Prescriptions Enhance Growth Performance of Heat Stressed Beef Cattle by Relieving Heat Stress Responses and Increasing Apparent Nutrient Digestibility

Song, Xiaozhen,Luo, Junrong,Fu, Daibo,Zhao, Xianghui,Bunlue, Kornmatitsuk,Xu, Zhensong,Qu, Mingren Asian Australasian Association of Animal Productio 2014 Animal Bioscience Vol.27 No.10

The present aim was to investigate the effects of traditional Chinese medicine prescriptions (TCM) on body temperature, blood physiological parameters, nutrient apparent digestibility and growth performance of beef cattle under heat stress conditions. Twenty-seven beef cattle were randomly divided into three groups as following; i) high temperature control (HTC), ii) traditional Chinese medicine prescriptions I+high temperature (TCM I) and iii) traditional Chinese medicine prescriptions II+high temperature (TCM II) (n = 9 per group). The results showed that the mean body temperature declined in TCM II treatment (p<0.05). Serum $T_3$ and $T_4$ levels with TCM I and TCM II treatments elevated (p<0.05), and serum cortisol levels of TCM I treatments decreased (p<0.05), compared with the HTC group. Total protein, albumin, globulin in TCM II treatments elevated and blood urea nitrogen levels of both TCM treatments increased, but glucose levels of both TCM treatments decreased, compared with the HTC group (p<0.05). The apparent digestibility of organic matter and crude protein with TCM I treatment increased, and the apparent digestibility of acid detergent fiber elevated in both TCM treatments (p<0.05). Average daily feed intake was not different among three groups, however average daily gain increased and the feed:gain ratio decreased with both TCM treatments, compared with the HTC group (p<0.05). The present results suggest that dietary supplementation with TCM I or TCM II improves growth performance of heat stressed beef cattle by relieving heat stress responses and increasing nutrient apparent digestibility.

Reliability and Validity of Chinese Version of the Perceived Competence Scale for Disaster Mental Health Workforce: A Cross-Sectional Study

Qingqing Xiao(Qingqing Xiao),Xiaozhen Song(Xiaozhen Song),Xuehua Huang(Xuehua Huang),Xiandong Meng(Xiandong Meng) 대한신경정신의학회 2023 PSYCHIATRY INVESTIGATION Vol.20 No.3

Objective This study aimed to translate the English version of the Perceived Competence Scale for Disaster Mental Health Workforce (PCS-DMHW) into Chinese, and to test its reliability and validity in Chinese mental health workers.Methods With the consent of Professor Choi, Keimyung University, Korea, and the authorization of the scale, the English version of PCS-DMHW was translated, retranslated and culturally debugged to form the Chinese version of PCS-DMHW. The general information questionnaire and the Chinese version of PCS-DMHW scale were used to investigate 706 mental health workforce from 9 tertiary hospitals in Sichuan province in China from March 24, 2020 to April 14, 2020. The Cronbach’s α coefficient was used to evaluate the internal consistency reliability of the scale, and the test-retest correlation coefficient r was used to evaluate the test-retest reliability of the scale. The content validity indexes (CVI) and exploratory factor analysis (EFA) was used separately for evaluating the content validity and structure validity of the scale.Results The Cronbach’s α coefficient of the Chinese version of PCS-DMHW total scale, individual competences and organizational competences subscale was 0.978, 0.956, and 0.964, respectively. The test-retest reliability of the total scale, individual competences and organizational competences subscale was 0.949, 0.932 and 0.927, respectively. The item-level CVI of all scale were ranged from 0.833-1.000, the scale-level CVI (S-CVI)/universal agreement of the total scale, individual competences and organizational competences subscale was 0.833, 0.875, and 0.857, respectively, and the S-CVI/average was 0.972, 0.979, and 0.976, respectively. EFA showed that two principal components were extracted from the subscale of individual competences and organizational competences.Conclusion The Chinese version of PCS-DMHW has good reliability and validity, and can be widely used in China.

Acoustic Radiation and Dynamic Study of a Steel Beam Damped with Viscoelastic Material

Quanmin Liu,Xiaozhen Li,Peipei Xu,Linya Liu,Yun-Lai Zhou 대한토목학회 2020 KSCE JOURNAL OF CIVIL ENGINEERING Vol.24 No.7

Steel structures subject to dynamic loads are prior to generate excessive vibration and noise. Viscoelastic treatment is an effective measure to mitigate the vibration and noise from thin-walled structures in a broad frequency range. H-shaped steel beams are widely used in civil engineering. So an experiment system is established and a series of impact hammer tests are conducted to assess the modal parameters, dynamic response and acoustic behaviour of an H-shaped steel beam coated with various viscoelastic treatments. Firstly, the spectra of the velocity response and acoustic radiation of the bare beam are analysed based on the tested data. Secondly, the resonance frequencies and modal loss factors of the beam with various viscoelastic treatments derived from the frequency response function are compared. Finally, the effect of the layout and thickness of viscoelastic patches on the mitigation of vibration and noise is discussed experimentally. It is shown that the modal loss factor of the first mode increases from 0.012 to 0.191 when the web is treated with 5 mm thick constrained layer damping (CLD). The viscoelastic patches on the web of the H-shaped beam are more effective to control the vibration and noise of the beam than the patches on the flanges. The viscoelastic treatment has distinct effect on the reduction of structural vibration and noise owing to the different dominant frequencies of vibration and noise as well as the frequency-dependent radiation efficiency. The normal velocity level of the H-shaped beam with an 8 mmthick web can be reduced by more than 10 dB and the sound pressure level around the beam about 8 dB when the web is partially covered with the constrained layer damping composed of 2.0 mm thick damping layer and 3.0 mm thick constraining layer.