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A self-adaptive correction method for perspective distortions of image

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Frontiers of Computer Science 2019年第3期13卷 588-598页

作者： Lihua WU Qinghua SHANG Yupeng SUN xu bai School of Measurement and Communication Harbin University of Science and Technology Harbin 150080 China

Frequently, the shooting angles available to photograph an object are limited, and the resultant images contain perspective distortions. These distortions make more difficult to perform subsequent tasks like feature extraction and information identification. This paper suggested a perspective correction method that extracts automatically distortion features through edge detection. Results showed that this method is powerful in correcting images with perspective distortions. The corrected image has virtually little information missing, clear features and high recovery rate.

关键词： perspective correction perspective transformation Hough transform edge detection

牦牛STAG3基因克隆及其在不同年龄段牦牛睾丸中的表达定位

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农业生物技术学报 2024年第2期32卷 344-354页

作者：石军陈文丽白旭李建富袁宝赵兴绪张全伟甘肃农业大学生命科学技术学院甘肃省动物生殖生理及繁殖调控重点实验室甘肃农业大学动物医学院

基质抗原3(stromal antigen 3, STAG3)是黏连蛋白复合体的重要成分之一，在动物卵泡发育、卵巢早衰和癌症发生等生物学过程中发挥重要调节作用，其在牦牛(Bos grunniens)生殖和发育过程中的作用尚不明确。本研究以不同岁龄(2, 4, 6和8岁... 详细信息

基质抗原3(stromal antigen 3, STAG3)是黏连蛋白复合体的重要成分之一，在动物卵泡发育、卵巢早衰和癌症发生等生物学过程中发挥重要调节作用，其在牦牛(Bos grunniens)生殖和发育过程中的作用尚不明确。本研究以不同岁龄(2, 4, 6和8岁龄)牦牛睾丸组织为材料，通过反转录PCR(reverse transcription-PCR, RT-PCR)克隆STAG3基因编码区序列(CDS)，利用STRING蛋白质互作数据库(STRING:functional protein association networks)和基因本体(Gene Ontology, GO)预测分析STAG3互作蛋白及生物学功能；通过苏木精-伊红(hematoxylin-eosin, HE)染色观察不同年龄牦牛睾丸组织形态结构；免疫组织化学(immunohistochemistry, IHC)染色和qRT-PCR分析STAG3分布及表达规律。结果显示，牦牛STAG3基因CDS区全长3 679 bp，开放阅读框为1 659 bp，编码552个氨基酸，蛋白无跨膜结构区，可能参与第一次减数分裂、联会复合和染色体浓缩等生物学过程；STAG3蛋白在各年龄段牦牛睾丸组织中均有表达，主要定位于初级精母细胞和次级精母细胞；2岁龄牦牛睾丸组织STAG3表达最高，且随年龄增长表达逐渐降低。结果表明，STAG3在动物进化中较为保守，各年龄段牦牛睾丸组织均有表达，其可能在牦牛生殖过程中发挥重要作用。本研究为解析牦牛生殖过程中STAG3功能及调控机制提供了参考依据。

关键词：牦牛基质抗原3(STAG3) 基因克隆生物信息学分析

Prediction Model of Kinetic Energy Conversion of Tandem Dual-Oscillator Based on Flow-Induced Vibration Experiment

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China Ocean Engineering 2022年第5期36卷 707-719页

作者： bai xu SUN Meng HAN Chuan-yu SUN Hai School of Naval Architecture&Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China Marine Renewable Energy Laboratory Department of Naval Architecture&Marine EngineeringUniversity of MichiganAnn Arbor MI 48109-2145USA College of Aerospace and Civil Engineering Harbin Engineering UniversityHarbin 150001China

Flow-induced vibration energy harvesting devices typically use an elastically supported body immersed in an oncoming flow to convert the sea and river current's hydrokinetic energy into electrical *** proportion of energy the device collects is greatly influenced by parameters such as the water flow velocity,spacing between device components,structure size,and damping *** parameter optimization and performance predictions of flow-induced vibration energy harvesting devices,we train a model of the power harvesting efficiency under different damping ratios,stiffnesses,spacing ratios,and reduced velocities based on experimental *** improve the prediction accuracy,a feedforward network structure is optimized by using the topological evolutionary algorithm and a radial basis function *** analysis reveals that the radial basis function network model provides the best agreement with the experimental results and realizes accurate predictions of the power harvested by a dual-oscillator system in the vortex-induced vibration,transition region,and *** prediction results show that the model's maximum power harvesting efficiency occurs in the vortex-induced *** efficiency increases and then decreases with increasing stiffness and reduced velocity in this phase;an increase in the spacing ratio causes the effi-ciency to decrease and then increase;finally,increasing the damping ratio enhances the *** device achieves maximum power harvesting efficiency at a reduced velocity of U_(r)=*** proposed model effectively predicts the maximum efficiency and the corresponding damping ratio and stiffness of the vortex-induced vibration and galloping,providing a new method for predicting tandem dual-oscillator hydrodynamic power conversion in flow-induced vibration.

关键词： flow-induced vibration tandem double-oscillator radial basis function prediction

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四种水溶性毒物中毒机理及检测方法研究进展

刑事技术 2024年第2期49卷 171-176页

作者：梁如柯白旭辛国斌张高勤朱军山西医科大学山西晋中030600 山西省公安厅刑事科学技术研究所山西晋中030601 北京市公安司法鉴定中心法庭毒物分析公安部重点实验室北京100192 公安部鉴定中心北京100038

水溶性毒物是指在水中具有较高溶解度的毒物,一般具有吸收迅速及毒性较高的特点,极易通过血液循环分布到体内各器官组织,从而对人体造成危害。本文选择氰化物、亚硝酸盐、氟乙酸钠和硼砂四种常见水溶性毒物,对其理化性质、毒理机制、中... 详细信息

水溶性毒物是指在水中具有较高溶解度的毒物,一般具有吸收迅速及毒性较高的特点,极易通过血液循环分布到体内各器官组织,从而对人体造成危害。本文选择氰化物、亚硝酸盐、氟乙酸钠和硼砂四种常见水溶性毒物,对其理化性质、毒理机制、中毒症状、体内代谢过程及国内外检测技术发展现状和未来趋势进行综述,希望为法庭科学水溶性毒物检验鉴定和中毒死亡案件原因调查提供参考。

关键词：法医毒物学亚硝酸盐氰化物氟乙酸钠硼砂水溶性毒物

3D non-isothermal phase-field simulation of microstructure evolution during selective laser sintering

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npj Computational Materials 2019年第1期5卷 442-453页

作者： Yangyiwei Yang Olav Ragnvaldsen Yang bai Min Yi bai-Xiang xu Mechanics of Functional Materials Division Institute of Materials ScienceTechnische Universität Darmstadt64287 DarmstadtGermany Department of Materials Science and Engineering Norwegian University of Science and Technology7491 TrondheimNorway State Key Laboratory of Mechanics and Control of Mechanical Structures&Key Laboratory for Intelligent Nano Materials and Devices of Ministry of Education&College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics(NUAA)210016 NanjingChina

During selective laser sintering(SLS),the microstructure evolution and local temperature variation interact *** of conventional isothermal sintering model is thereby insufficient to describe *** this work,we construct our model from entropy level,and derive the non-isothermal kinetics for order parameters along with the heat transfer equation coupled with microstructure *** from partial melting and laser-powder interaction are also *** then perform 3D finite element non-isothermal phase-field simulations of the SLS single *** confront the high computation cost,we propose a novel algorithm analogy to minimum coloring problem and manage to simulate a system of 200 grains with grain tracking algorithm using as low as 8 non-conserved order ***,applying the model to SLS of the stainless steel 316L powder,we identify the influences of laser power and scan speed on microstructural features,including the porosity,surface morphology,temperature profile,grain geometry,and *** further validate the first-order kinetics of the transient porosity during densification,and demonstrate the applicability of the developed model in predicting the linkage of densification factor to the specific energy input during SLS.

关键词： microstructure isothermal kinetics

Respiratory manifestations in amyloidosis

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Chinese Medical Journal 2005年第24期118卷 2027-2033页

作者： xu Ling CAI bai-qiang ZHONG xu ZHU Yuan-jue Department of Respiratory Medicine Peking Union Medical CollegeHospital Peking Union Medical College Chinese Academy ofMedical Sciences Beijing 100730 China

Background Amyloidosis is a collection of diseases in which different proteins are deposited. Amyloid deposits occur in systemic and organ-limited forms. In both systemic and localized forms of the disease, lung can he involved. The aim of this study was to explore the different respiratory manifestations of amyloidosis. Methods Chest radiology, clinical presentations, bronchoscopic/laryngoscopic findings and lung function data of 59 patients with amyloidosis involving respiratory tract collected during January 1986 to March 2005, were analysed. Results Of the 16 cases with localized respiratory tract amyloidosis, 8 had the lesions in the trachea and the bronchi, 2 in the larynx and the trachea, 5 in the larynx and/or the pharynx, and 1 in the lung parenchyma. Of 43 systemic amyloidosis with respiratory tract involvement, 3 had the lesions in bronchi, 13 in lung parenehyma, 33 in pleura, 8 in mediastina, 1 in nose and 1 in pharynx. Chest X-rays were normal in most cases of tracheobronchial amyloidosis. CT, unlike chest X-rays, showed irregular luminal narrowing, airway wall thickening with calcifications and soft tissue shadows in airway lumen. Localized lung parenchymal amyloidosis presented as multiple nodules. Multiple nodular opacities, patch shadows and reticular opacities were the main radiological findings in systemic amyloidosis with lung parenchymal involvement. In pleural amyloidosis, pleural effusions and pleural thickening were detected. Mediastinal and/or hilar adenopathy were also a form of lung involvement in systemic amyloidosis. The major bronehoseopie findings of tracheobronchial amyloidosis were narrowing of airway lumen, while nodular, ＇ tumour like＇ or ＇ bubble like＇ masses, with missing or vague cartilaginous rings, were detected in about half of the patients. Conclusions Localized respiratory tract amyloidosis mostly affects the trachea and the bronchi. Chest X-rays are not sensitive to detect these lesions. Systemic amyloidosis often invo

关键词： amyloiclosis trachea bronchus lung pleural effusion

Voltage-driven charge-mediated fast 180 degree magnetization switching in nanoheterostructure at room temperature

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npj Computational Materials 2017年第1期3卷 137-145页

作者： Min Yi Hongbin Zhang bai-Xiang xu Department of Materials and Earth Sciences Technische Universitat Darmstadt64287 DarmstadtGermany

Voltage-driven 180°magnetization switching without electric current provides the possibility for revolutionizing the *** demonstrated the voltage-driven charge-mediated 180°magnetization switching at room temperature by combining firstprinciples calculations and temperature-dependent magnetization dynamics *** electric field(E)-induced interface charge is found to allow a giant modulation of the magnetic anisotropy(K)of the *** K is revealed to vary linearly with respect to E and the epitaxial *** dynamics simulations using the so-obtained K show that both inplane and perpendicular 180°switching can be achieved by E *** temperature effect renders the 180°switching as probability *** analysis indicates a fast(around 4 ns)and low-error-probability 180°switching achievable at room temperature by controlling the magnitude of E and the pulse *** study inspires the rational design of miniaturized nanoscale spintronic devices where thermal fluctuation has a great impact.

关键词： magnetization charge render

苏南太湖流域农田土壤重金属输入输出清单构建及风险预警

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中国环境科学 2024年第9期44卷 5085-5098页

作者：杨雳董欣平林静薄文浩白宗旭陈涛西北农林科技大学资源环境学院陕西杨凌712100 农业农村部西北植物营养与农业环境重点实验室陕西杨凌712100

为指导产地环境管理策略、巩固污染防治成果,以公开数据为基础构建了苏南太湖流域农田土壤重金属的输入输出清单,探究了土壤中八大重金属元素(As、Cd、Cr、Cu、Hg、Ni、Pb和Zn)的累积现状并预测了未来发展趋势.其中,输入途径主要包括大... 详细信息

为指导产地环境管理策略、巩固污染防治成果,以公开数据为基础构建了苏南太湖流域农田土壤重金属的输入输出清单,探究了土壤中八大重金属元素(As、Cd、Cr、Cu、Hg、Ni、Pb和Zn)的累积现状并预测了未来发展趋势.其中,输入途径主要包括大气沉降、畜禽粪便、灌溉水和化肥农药施用,输出途径主要包括作物收获和土壤渗流.结果表明,As、Cd、Cu、Cr和Hg元素主要通过灌溉用水输入农田,Ni主要通过大气沉降、化肥施用和灌溉水输入农田,Pb和Zn主要通过大气沉降进入农田;As、Cr、Cu、Hg和Pb主要通过土壤渗流输出农田,Cd和Zn主要通过作物收获输出农田.Cd是苏南太湖流域农田土壤中最需关注的重金属元素,在短期内其可能达到风险阈值,其余重金属元素均存在不同程度累积但远未达到风险阈值.

关键词：输入输出清单农田土壤重金属风险预警太湖流域

Electric field induced magnetization reversal in magnet/insulator nanoheterostructure

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International Journal of Smart and Nano Materials 2020年第3期11卷 298-309页

作者： Qihua Gong Min Yi bai-Xiang xu Institute of Materials Science Technische Universität DarmstadtDarmstadtGermany State Key Lab of Mechanics and Control of Mechanical Structures&Key Lab for Intelligent Nano Materials and Devices of Ministry of Education&College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics(NUAA)NanjingChina

Electric-field control of magnetization reversal is promising for lowpower *** in a magnet/insulator nanoheterostructure which is the fundamental unit of magnetic tunneling junction in spintronics,we demonstrate the electric field induced 180°magne-tization switching through a multiscale study combining firstprinciples calculations and finite-temperature magnetization *** the model nanoheterostructure MgO/Fe/Cu with insu-lator MgO,soft nanomagnet Fe and capping layer Cu,through firstprinciples calculations we find its magnetocrystalline anisotropy linearly varying with the electric *** finite-temperature magnetization dynamics which is informed by the first-principles results,we disclose that a room-temperature 180°magnetization switching with switching probability higher than 90%is achievable by controlling the electric-field pulse and the nanoheterostructure *** 180°switching could be fast realized within 5 *** study is useful for the design of low-power,fast,and miniaturized nanoscale electric-field-controlled spintronics.

关键词： Magnetization reversal nanoheterostructure electric field spintronics multiscale simulations switching probability