面向视觉问答的多模块协同注意模型

视觉问答（VQA）是计算机视觉和自然语言处理领域中典型的多模态问题，然而传统VQA模型忽略了双模态中语义信息的动态关系和不同区域间丰富的空间结构。提出一种新的多模块协同注意力模型，对视觉场景中对象间关系的动态交互和文本上下文表示进行充分理解，根据图注意力机制建模不同类型对象间关系，学习问题的自适应关系表示，将问题特征和带关系属性的视觉关系通过协同注意编码，加强问题词与对应图像区域间的依赖性，通过注意力增强模块提升模型的拟合能力。在开放数据集VQA 2.0和VQA-CP v2上的实验结果表明，该模型在“总体”、“是/否”、“计数”和“其他”类别问题上的精确度明显优于DA-NTN、ReGAT和ODA-GCN等对比方法，可有效提升视觉问答的准确率。     

Evolution of microstructure and electrical properties of Aurivillius phase (CaBi4Ti4O15)1-x(Bi4Ti3O12)x ceramics

(CaBi₄Ti₄O₁₅)_1-x(Bi₄Ti₃O₁₂)_x (CBT-xBIT) Aurivillius phase ceramics were synthesized by the conventional solid reaction method. The evolution of the structure and the electrical properties of CBT-xBIT ceramics were systematically investigated. Due to the enhanced spontaneous polarization induced by internal stresses on the Bi₂O₂ layers in the CBT-xBIT structure, the optimal piezoelectric coefficient (d₃₃ ~ 13?pC/N) was obtained in the ceramics with x?=?0.3 while exhibiting a relatively good thermal stability in the temperature range of 20–700?°C. The dc resistivity (ρ_dc) of the CBT-xBIT ceramics exhibited a higher value (≥?10⁹ Ω?cm) at room temperature, and the tan δ value of CBT-xBIT (x= 0, 0.1 and 0.3) within the temperature range of 20–500?°C maintained stability as a result of the domain structure and point defect concentration in the ceramics. In addition, a distinctive double dielectric peak anomaly was observed in the ε_r-T curves of the CBT-xBIT (x= 0.3, 0.5 and 0.7) ceramics, and it plays a remarkable role in the thermal stability of the piezoelectricity of CBT-xBIT ceramics. As a result, such research can benefit high temperature practical piezoelectric devices.     

Recent advances in the technology of quick-frozen baozi: a review

Baozi is a traditional staple steamed food in China. Current consumer trends urge the production of quick-frozen baozi on large scales and the formulation of healthier varieties. These demands require a better definition of the relationship between the raw material and/or technological factors and the quality of the quick-frozen baozi to be developed. This review summarised the recent advances made in understanding the roles of the production process and the ingredients in the appearance, texture, sensory characteristics, nutrition and shelf-life properties of quick-frozen baozi. The mechanism of the chemical changes of each component and physical changes of the dough blank during each processing stage is reviewed. In addition, suggestions for further research to improve the quality of frozen steamed products have been proposed.     

6M25-185／31．4A压缩机活塞杆改造

6M25—185／31．4A氢氮压缩机一、二、六段活塞杆断裂。论述断裂原因及解决改造方法。     

The optimization of aqueous two‐phase extraction of lysozyme from crude hen egg white using response surface methodology

BACKGROUND: Aqueous two‐phase extraction is a versatile method for separating biological particles and macromolecules. In the present wok, the feasibility of using PEG 4000/potassium citrate aqueous two‐phase system (ATPS) for recovering and purifying lysozyme was investigated. Response surface methodology was used to determine an optimized ATPS for purification of lysozyme from crude hen egg white. RESULTS: Mathematical models concerning the purification of lysozyme from chicken egg white in polyethylene glycol 4000 (PEG 4000)/potassium citrate ATPS are established using response surface methodology. Screening experiments using fractional factorial designs show that the pH of the system significantly affects the recovery and purification of lysozyme. An optimized ATPS was proved to be at pH 5.5 and 30 °C and contained 18% (w/w) PEG, 16% (w/w) potassium citrate, 3.75% (w/w) potassium chloride (KCl). Under those conditions, the specific activity, purification factor and activity yield for lysozyme were 31100 U mg^?1, 21.11 and 103%, respectively. CONCLUSION: The PEG 4000/potassium citrate ATPS has the potential to be applied to establish bioprocesses for the primary recovery and partial purification of lysozyme. © 2012 Society of Chemical Industry     

Degradable and Excretable Ultrasmall Transition Metal Selenide Nanodots for High-Performance Computed Tomography Bioimaging-Guided Photonic Tumor Nanomedicine in NIR-II Biowindow

Transition metal selenide nanodots (NDs) represent distinctive antitumor agents for cancer treatment, but their non-biodegradability may bring serious adverse effects and potential long-term toxicity to internal tissues/organs, which substantially hinder their further clinical translations. In this work, the construction of a multifunctional theranostic nanosystem based on degradable and excretable ultrasmall Rh₃Se₈ NDs by a general bovine serum albumin-templated strategy is reported. The constructed Rh₃Se₈ NDs exhibit distinctively high photothermal-conversion efficiency (57.5%) in the second near-infrared biowindow, making them highly applicable for photoacoustic imaging and photonic hyperthermia at the desired wavelength. Rh₃Se₈ NDs exhibit a high tumor growth inhibition rate (98.1%) on 4T1 breast tumor-bearing mice due to the desirable photonic hyperthermia performances. Especially, the fabricated Rh₃Se₈ NDs feature the large X-ray attenuation coefficients of the Rh component for contrast-enhanced X-ray computed tomography imaging. Importantly, the prominent biodegradability of Rh₃Se₈ NDs enables their quick excretion out of the body for potentially avoiding inflammation and mitigating long-term toxicity. Therefore, this work highlights the construction of proof-of-concept biodegradable and excretable ultrasmall inorganic theranostic nanosystems for multiple bioimaging-guided cancer nanotherapeutics, guaranteeing the further clinical translations of inorganic nanoparticles in biomedicine.     

Nanoporous bismuth electrocatalyst with high performance for glucose oxidation application

Although direct glucose fuel cell (DGFC) is widely regarded as one of the most promising energy systems, the low catalytic activity and inferior instability of most anode catalysts during electro-oxidation of glucose has greatly hampered its potential applications. In this work, an efficient and durable anode catalyst of nanoporous bismuth (Bi) for the alkaline electro-oxidation of glucose was proposed just by a simple de-alloying method. The microstructure and catalytic performance of nanoporous bismuth could be finely tuning through actively controlling the composition of precursor Mg–Bi alloy. A three-dimension structure was formed after de-alloying Mg–Bi precursor, giving rise to an increased specific surface area and correspondingly resulting in an enhanced electro-catalytic performance. It has intimated that the optimal nanoporous Bi catalyst with an open, bi-continuous interpenetrating pore-to-ligament structure was constructed based on Mg₆₅Bi₃₅ alloy etching and exhibited an enhanced current density (as high as 8.04 mA/cm²) during alkaline electro-oxidation of glucose, together with the lowest poisoning rate of 5.6 × 10^?3%. The remarkable electrochemical performance of the nanoporous Bi catalyst, coupling with facile dealloying strategy may facilitate design and development of renewable energy device.     

频谱资源经济价值评估和定价机制研究及展望

首先从自然资源价值的角度，对频谱资源的价值构成、时间性、整体性、结构性、社会性等价值特征以及价值存在形式进行阐述，并尝试给出频谱资源经济价值评估和频谱资源定价的定义和内涵，最后对基于频谱费的定价方法、基于行政管理费的定价方法、基于用户总收入的定价方法和机会成本法 4 种频谱资源定价方法，以及调研了解的部分国家采用的频谱资源定价方法进行梳理分析，并就我国进一步完善频谱资源经济价值评估和定价机制提出了建议。     

复杂地质条件下外海风电场高桩承台基础植入式嵌岩桩施工技术

在外海风电站工程中,基础结构形式普遍采用高桩承台基础,嵌岩施工时将面临施工工艺复杂、工序烦琐、所需各种专用船机设备型号多等难题.结合工程实例,从成孔、钢管桩植入、封底混凝土浇筑等方面,总结了高桩承台基础植入式嵌岩桩的关键施工技术,可为类似工程提供参考.