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基于改进生成对抗网络的半监督语义分割

四川大学学报（自然科学版） 2024年第5期61卷 99-107页

作者：王小成胡亚琦王一中兰州交通大学电子与信息工程学院兰州730070

为了解决对抗式半监督语义分割网络在训练过程中稳定性较差,传统语义分割网络难以对像素之间远距离依赖关系建模等问题,提出了一种结合谱归一化生成对抗网络和坐标注意力机制的半监督语义分割网络.利用谱归一化使对抗网络判别器满足利... 详细信息

为了解决对抗式半监督语义分割网络在训练过程中稳定性较差,传统语义分割网络难以对像素之间远距离依赖关系建模等问题,提出了一种结合谱归一化生成对抗网络和坐标注意力机制的半监督语义分割网络.利用谱归一化使对抗网络判别器满足利普西茨连续性,从而提高了网络训练过程的稳定性且避免了梯度消失的问题;在分割网络中融入坐标注意力机制,使网络能够获取远距离像素之间的依赖关系,并扩大感受野.与基准模型相比,在PASCAL VOC 2012增强数据集中采用1/50、1/20和1/8标记数据集时,MIoU分别提升了2.2%、1.4%和1.8%;在Cityscapes城市街景数据集中采用1/8、1/4和1/2标记数据集时,MIoU分别提升了1.9%、2.1%和1.3%.实验结果证明,与其他基于对抗学习的半监督语义分割网络相比,该算法在半监督语义分割任务中具有较好的稳定性和准确性.

关键词：语义分割半监督学习生成对抗网络谱归一化注意力机制

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Optimized XML Storage in NXD Based on Tree-Structure Disassemble

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Wuhan University Journal of Natural Sciences 2006年第1期11卷 93-99页

作者： LIU Yun-sheng wang yi zhong Hao School of Computer Science and Technology Huazhong University of Science and Technology Wuhan 430074Hubei China

Independent XML storage based on XSD （XML Schema Document） is adopted in NXD（Native XML Data base）, XMI. storage structure based on tree-structure disassemble and the algorithm used in dynamically updating XML document are provided in this paper. The main idea is that in term of data model of XML document, XML document is parsed to Document Structure-Tree with Hierarchical Model and Leaf-Data with Relation Model for storage. Simultaneously Proxy node is imported in order to solve the problem that XML data store in cross-blocks. And with XSD model information, sparse index is constructed to save storage space. It is proved that this storage structure could improve efficiency of XML document operation.

关键词： XML storage storage model NXD (native XML database) document trees regular expression

金鱼草GAE基因家族鉴定及核盘菌抗性基因挖掘

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农业生物技术学报 2024年第9期32卷 2049-2059页

作者：夏文念杨冬梅宋佳怡杨洁汪仲毅蔺海娣胡慧贞西南林业大学园林园艺学院/云南省功能性花卉资源及产业化技术工程研究中心

果胶是植物细胞壁的重要成分，在植物生长发育和细胞壁抗性中发挥重要作用，合成其骨架结构的单糖供体—UDP-半乳糖醛酸(UDP-α-D-galacturonic acid, UDP-GalA)由葡萄糖醛酸异构酶(UDP-Dglucuronate 4-epimerase, GAE)催化合成。为了... 详细信息

果胶是植物细胞壁的重要成分，在植物生长发育和细胞壁抗性中发挥重要作用，合成其骨架结构的单糖供体—UDP-半乳糖醛酸(UDP-α-D-galacturonic acid, UDP-GalA)由葡萄糖醛酸异构酶(UDP-Dglucuronate 4-epimerase, GAE)催化合成。为了探究金鱼草(Antirrhinum majus) GAE家族成员介导的细胞壁抗性，本研究在全基因组水平鉴定出了8个AmGAEs基因，对其理化性质、亚细胞定位、系统发育、保守基序、基因结构、染色体定位和顺式作用元件等进行生物信息学分析，发现AmGAE家族成员均为碱性亲水蛋白，定位于高尔基体，其基因启动子区域具有防御和胁迫、茉莉酸甲酯(methyl jasmonate, MeJA)、水杨酸(salicylic acid, SA)和脱落酸(abscisic acid, ABA)等响应元件。进一步对金鱼草抗、感核盘菌(Sclerotinia sclerotiorum)材料进行转录组测序(RNA-seq)分析和实时荧光定量PCR (quantitative real-time PCR, qRT-PCR)验证，发现AmGAE1a、AmGAE3、AmGAE5和AmGAE2基因表达在抗性材料Am6 (R)中显著被诱导，而AmGAE7和AmGAE4基因表达则在感病材料Am1 (S)中显著被诱导，其中AmGAE1a、AmGAE3、AmGAE7和AmGAE4基因在qRT-PCR中的表达模式与RNA-seq的差异表达结果一致，确定为金鱼草抗核盘菌的候选基因。本研究为深入探讨AmGAE家族基因抗核盘菌的分子机制提供了理论基础和新的基因资源。

关键词：金鱼草 GAE基因家族核盘菌抗性转录组分析候选基因挖掘

金鱼草WAK/WAKL基因家族鉴定及抗核盘菌候选基因挖掘

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南方农业学报 2024年第1期55卷 24-36页

作者：杨冬梅夏文念宋佳怡杨洁严苍海苏芸丽汪仲毅胡慧贞西南林业大学园林园艺学院/云南省功能性花卉资源及产业化技术工程研究中心云南昆明650224

【目的】鉴定金鱼草细胞壁相关受体激酶(Wall-associated kinase,WAK)及类WAK蛋白(WAK-like kinases,WAKL)基因家族成员,并挖掘抗核盘菌的候选基因,为深入解析金鱼草抗核盘菌的WAK/WAKL分子调控机制提供理论参考。【方法】以拟南芥WAK/W... 详细信息

【目的】鉴定金鱼草细胞壁相关受体激酶(Wall-associated kinase,WAK)及类WAK蛋白(WAK-like kinases,WAKL)基因家族成员,并挖掘抗核盘菌的候选基因,为深入解析金鱼草抗核盘菌的WAK/WAKL分子调控机制提供理论参考。【方法】以拟南芥WAK/WAKL家族蛋白为参考序列,利用生物信息学方法从金鱼草基因组数据库中鉴定出WAK/WAKL基因家族成员,并对其理化性质、系统发育、基因结构、保守基序、顺式作用元件及共线性关系等进行预测分析,并通过转录组测序和实时荧光定量PCR对该家族基因在金鱼草抗感核盘菌材料中的表达模式进行分析。【结果】从金鱼草基因组中共鉴定出27个WAK/WAKL基因家族成员,其中WAK家族基因16个(AmWAK1~AmWAK16),WAKL家族基因11个(AmWAKL1~AmWAKL11),编码的氨基酸数量为615~1085个;理论等电点(pI)为4.94~8.69,绝大多数蛋白呈酸性;所有蛋白的总平均亲水性指数(GRAVY)值小于0,均为亲水性蛋白;大多数蛋白亚细胞定位于细胞质膜区域,少部分定位于细胞外、液泡、高尔基体和细胞核。27个WAK/WAKL基因家族成员不均匀地分布在金鱼草的8条染色体上,且与拟南芥WAK/WAKL家族基因存在7对共线性同源基因;基因启动子区域含有与防御和胁迫响应、茉莉酸甲酯响应及水杨酸响应等顺式作用元件。通过叶片离体接种核盘菌试验,筛选出抗性差异明显的易感病品种Am1和抗病品种Am6。有12个WAK/WAKL家族基因在金鱼草抗感材料中显著差异表达(P<0.05),有9个基因表达模式与转录组测序结果基本一致。这9个基因中,有5个基因(AmWAK7、AmWAKL2、AmWAKL8、AmWAK6和AmWAK13)在金鱼草的根、茎和叶组织中高表达,而剩余4个基因(AmWAK2、AmWAK8、AmWAK9和AmWAK12)在根、茎和叶中基本不表达。【结论】筛选出的27个金鱼草WAK/WAKL基因家族成员,具有相似的基因结构和蛋白功能结构域,其中AmWAK6、AmWAK7、AmWAK13、AmWAKL2和AmWAKL8为金鱼草抗核盘菌的关键候选基因,具有介导抗病的潜在功能。

关键词：金鱼草 WAK/WAKL基因家族鉴定核盘菌抗性转录组测序候选基因挖掘

Effects of Magnesium and Ferric Ions on Crystallization of Calcium Sulfate Dihydrate Under the Simulated Conditions of Wet Flue-gas Desulfurization

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Chemical Research in Chinese Universities 2008年第6期24卷 688-693页

作者： GAO Xiang HUO wang zhong yi LUO zhong-yang CEN Ke-fa NI Ming-jiang CHEN Le-ming State Key Laboratory of Clean Energy Utilization Institute of Thermal Energy and Power Engineering Zhejiang University Hangzhou 310027 P. R. China

The influences of magnesium and ferric ions in their different ratios on the rate of gypsum crystallization were studied under the conditions similar to those of wet flue-gas desulfurization（WFGD）. The results show that addition of both Mg^2＋ and Fe^3＋ increased induction time and decreased the growth efficiency up to 50% compared with the baseline（without impurities） depending on the concentration and the type of impurity. The effects of Mg^2＋ and Fe^3＋ on the surface energy and the rate of nucleation were estimated by employing the classical nucleation theory. The surface energy decreased by 8% and 14% with the addition of 0.02 mol/L magnesium or ferric ions, respectively, compared to the baseline. Mg^2＋ and Fe^3＋ made the growth rate of the （020）, （021） and （040） faces of gypsum crystal a much greater reduction, which leads to the formation of needle crystals compared to the baseline which favors the formation of plate or flakes. Furthermore, an edge detection program was developed to quantify the effects of impurities on the filtration rate of gypsum product. The results show that the inhibition efficiency of the presence of 0.02 mol/L Mg^2＋ and Fe^3＋ on the filtration rate of gypsum crystal ranges from 22% to 39%.

关键词： Calcium sulfate dihydrate Morphology Wet flue-gas desulfurization Filtration rate

Recent advances and key perspectives of in-situ studies for oxygen evolution reaction in water electrolysis

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Green Energy & Environment 2024年第10期9卷 1497-1517页

作者： yi wang Zichen Xu Xianhong Wu zhong-Shuai Wu State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences Shijingshan District Dalian National Laboratory for Clean Energy Chinese Academy of Sciences

Electricity-driven water splitting to produce hydrogen is one of the most efficient ways to alleviate energy crisis and environmental pollution problems, in which the anodic oxygen evolution reaction(OER) is the key half-reaction of performance-limiting in water splitting. Given the complicated reaction process and surface reconstruction of the involved catalysts under actual working conditions, unraveling the real active sites, probing multiple reaction intermediates and clarifying catalytic pathways through in-situ characterization techniques and theoretical calculations are essential. In this review, we summarize the recent advancements in understanding the catalytic process, unlocking the water oxidation active phase and elucidating catalytic mechanism of water oxidation by various in-situ characterization techniques. Firstly, we introduce conventionally proposed traditional catalytic mechanisms and novel evolutionary mechanisms of OER, and highlight the significance of optimal catalytic pathways and intrinsic stability. Next, we provide a comprehensive overview of the fundamental working principles,different detection modes, applicable scenarios, and limitations associated with the in-situ characterization techniques. Further, we exemplified the in-situ studies and discussed phase transition detection, visualization of speciation evolution, electronic structure tracking, observation of reaction active intermediates, and monitoring of catalytic products, as well as establishing catalytic structure–activity relationships and catalytic mechanism. Finally, the key challenges and future perspectives for demystifying the water oxidation process are briefly proposed.

关键词： In-situ studies Water splitting Oxygen evolution reaction Catalytic mechanism

Reliable calculations of nuclear binding energies by the Gaussian process of machine learning

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Nuclear Science and Techniques 2024年第6期35卷 130-144页

作者： Zi-yi Yuan Dong Bai Zhen wang zhong-Zhou Ren School of Physics Science and Engineering Tongji UniversityShanghai 200092China College of Science Hohai UniversityNanjing 211100China Key Laboratory of Advanced Micro-Structure Materials Ministry of EducationShanghai 200092China

Reliable calculations of nuclear binding energies are crucial for advancing the research of nuclear physics. Machine learning provides an innovative approach to exploring complex physical problems. In this study, the nuclear binding energies are modeled directly using a machine-learning method called the Gaussian process. First, the binding energies for 2238 nuclei with Z > 20 and N > 20 are calculated using the Gaussian process in a physically motivated feature space, yielding an average deviation of 0.046 MeV and a standard deviation of 0.066 MeV. The results show the good learning ability of the Gaussian process in the studies of binding energies. Then, the predictive power of the Gaussian process is studied by calculating the binding energies for 108 nuclei newly included in AME2020. The theoretical results are in good agreement with the experimental data, reflecting the good predictive power of the Gaussian process. Moreover, the α-decay energies for 1169 nuclei with 50 ≤ Z ≤ 110 are derived from the theoretical binding energies calculated using the Gaussian process. The average deviation and the standard deviation are, respectively, 0.047 MeV and 0.070 MeV. Noticeably, the calculated α-decay energies for the two new isotopes ^ (204 )Ac(Huang et al. Phys Lett B 834, 137484(2022)) and ^ (207) Th(Yang et al. Phys Rev C 105, L051302(2022)) agree well with the latest experimental data. These results demonstrate that the Gaussian process is reliable for the calculations of nuclear binding energies. Finally, the α-decay properties of some unknown actinide nuclei are predicted using the Gaussian process. The predicted results can be useful guides for future research on binding energies and α-decay properties.

关键词： Nuclear binding energies decay Machine learning Gaussian process

Fuzzy Adaptive Control of Stochastic Nonlinear Systems with Unknown Virtual Control Gain Function

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自动化学报 2006年第2期32卷 170-178页

作者： wang ying-Chun ZHANG Hua-Guang wang yi-zhong Institute of Electrical Automation Northeastern University Shenyang 110004

The problem of track control is studied for a class of strict-feedback stochastic nonlinear systems in which unknown virtual control gain function is the main feature. First, the so-called stochastic LaSalle theory is extended to some extent, and accordingly, the results of global ultimate boundedness for stochastic nonlinear systems are developed. Next, a new design scheme of fuzzy adaptive control is proposed. The advantage of it is that it does not require priori knowledge of virtual control gain function sign, which is usually demanded in many designs. At the same time, the track performance of closed-loop systems is improved by adaptive modifying the estimated error upper bound. By theoretical analysis, the signals of closed-loop systems are globally ultimately bounded in probability and the track error converges to a small residual set around the origin in 4th-power expectation.

关键词：随机非线性系统模糊自适应控制虚拟控制增益函数

Novel Mechanism,Drug Target and Therapy in Epilepsy

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Neuroscience Bulletin 2024年第5期40卷 561-563页

作者： Cenglin Xu yi wang zhong Chen Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province School of Pharmaceutical ScienceZhejiang Chinese Medical UniversityHangzhou310053China

Epilepsy,which is characterized by unprovoked seizures and has a prevalence of nearly 1%,is becoming one of the leading causes of disability and death globally[1].The exact mechanisms behind epilepsy are still unknown,which contributes to the inadequate efficacy of anti-seizure medications(ASMs)that mainly target membrane ion channels and neurotransmission[2].

关键词： epilepsy Therapy death