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141.
谢俊 《数字社区&智能家居》2009,(36)
介绍了在Delphi环境下基于OLE技术和WORD对象模型实现通用题库中试题和试卷编辑、浏览的基本原理,并在此基础上给出了具体的实现过程。 相似文献
142.
葛华丽 《数字社区&智能家居》2009,(26)
该文介绍了一种基于知识点的,采用离散型随机变量的二项分布函数构造选题算法的方法。该算法把题型平均难度系数、题型个数作为主要控制目标,以包含题目题型作为主要条件筛选知识点,以此选择试题,而后对题目按知识点的各难度等级分类,从而按知识点选题组卷,并运用适当的组卷策略优化组卷结果。 相似文献
143.
赵丽维 《电脑编程技巧与维护》2009,(18):25-27
系统以英语教育为背景进行设计,旨在提供一个适合形成性测试和阶段性测试的自动组卷系统,能快速方便地提供各种要求的试卷,帮助教师把握教学的进度,及时地反馈教学中的问题,以使改进教学方法和调整教学重点。 相似文献
144.
系统以教育测量理论为基础,分析了试卷生成的约束条件,采用离散型随机变量的二项分布函数建立难度—分数对应关系模型,并以此为依据,利用自适应遗传算法生成和优化试卷。通过调用WebEditor插件,模拟Word环境,实现试题和试卷的操作,使命题环境更接近于传统命题环境;根据频繁访问数据库的特点,利用Hibernate进行对象和关系之间的映射,提高数据库访问效率,具备一定的稳定性和可移植性。 相似文献
145.
146.
油浸纸绝缘套管作为变压器的关键组件,其绝缘受损会威胁变压器主设备的运行安全。针对此现状,提出一种基于多源融合的油纸绝缘套管缺陷辨识及绝缘状态评估方法。首先,根据实际运行工况制备典型缺陷试验套管,并开展频域介电响应、局部放电及红外热成像联合试验,辨识套管缺陷种类。然后,提取套管绝缘指标量,引入隶属度函数及状态得分算子,建立基于博弈论组合赋权法的套管绝缘状态评估模型。最后,分别采用组合赋权法和单一赋权法的评估模型,对正常以及缺陷套管进行算例分析。结果表明:联合试验可以准确辨识套管缺陷种类。组合赋权法弥补了单一赋权法评估结果片面的不足,且正常套管的模型评估分数均高于缺陷套管。评估结果与套管实际绝缘状态一致,验证了套管绝缘状态评估模型的正确性及有效性。 相似文献
147.
Wenlong Li Haoxiang Chen Jingfeng Cai Miao Wang Xi Zhou Lei Ren 《Advanced functional materials》2023,33(49):2303147
Bacterial infection and impaired angiogenesis make the treatment of diabetic foot ulcers (DFU) extremely challenging. Cationic polymers are expected to treat infected wounds due to their excellent antibacterial properties, but still, it is difficult to meet the therapeutic needs of pro-angiogenesis and anti-infections due to their simple construction units and outmoded synthesis methods. Herein, a cationic poly(pentahydropyrimidine) (PPHP) library with strong modifiability is synthesized to construct a hybrid hydrogel with synergistic therapeutic effects for the treatment of infected DFUs. It is found that the as-synthesized hybrid hydrogel can up-regulate angiogenesis-related gene (HIF-1, VEGF, and bFGFR/bFGF) expression and targeted disruption of bacterial cell membranes, which finally promotes the healing of infected DFU (wound healing rate: 92%) within 10 days. This hydrogel, thus, holds great promise in developing new strategies to significantly enhance the treatment of DFU and other bacterial-infected pathological diagnoses. 相似文献
148.
Siyu Wang Yuqian Qiao Xiangmei Liu Shengli Zhu Yufeng Zheng Hui Jiang Yu Zhang Jie Shen Zhaoyang Li Yanqin Liang Zhenduo Cui Paul K. Chu Shuilin Wu 《Advanced functional materials》2023,33(3):2210098
Temperature variation-induced thermoelectric catalytic efficiency of thermoelectric material is simultaneously restricted by its electrical conductivity, Seebeck coefficient, and thermal conductivity. Herein, Bi2Te3 nanosheets are in situ grown on reduced graphene oxides (rGO) to generate an efficient photo-thermoelectric catalyst (rGO-Bi2Te3). This system exhibits phonon scattering effect and extra carrier transport channels induced by the formed heterointerface between rGO and Bi2Te3, which improves the power factor value and reduces thermal conductivity, thus enhancing the thermoelectric performance of 2.13 times than single Bi2Te3. The photo-thermoelectric catalysis of rGO-Bi2Te3 significantly improves the reactive oxygen species yields, resulting from the effective electron–hole separation caused by the unique thermoelectric field and heterointerfaces of rGO-Bi2Te3. Correspondingly, the electrospinning membranes containing rGO-Bi2Te3 nanosheets exhibit high antibacterial efficiency in vivo (99.35 ± 0.29%), accelerated tissue repair ability, and excellent biosafety. This study provides an insight into heterointerface design in photo-thermoelectric catalysis. 相似文献
149.
Kai Li Wenxiu Xu Yi Chen Xiaoyi Liu Lanbo Shen Junkun Feng WeiWei Zhao Wenjun Wang Junling Wu Baojin Ma Shaohua Ge Hong Liu Jianhua Li 《Advanced functional materials》2023,33(28):2214522
Treating bacterial biofilm infections on implanted materials remains challenging in clinical practice, as bacteria can be resistant by weakening the host defense from immune cells like macrophages. Herein, a metal-piezoelectric hetero-nanostructure with mechanical energy-driven antimicrobial property is in situ constructed on the Ti implant. Under ultrasonic irradiation, the formed piezotronic Ti (piezoTi) can promote the generation of reactive oxygen species (ROS) by facilitating local charge transfer at the surface, thus leading to piezodynamic killing of Staphylococcus aureus (S. aureus) while downregulating biofilm-forming genes. In addition, the stimulated macrophages on piezoTi display potent phagocytosis and anti-bacterial activity through the activation of PI3K-AKT and MAPK pathway. As a demonstration, one-time ultrasound irradiation of piezoTi pillar implanted in an osteomyelitis model efficiently eliminates the S. aureus biofilm infection and rescues the implant with enhanced osteointegration. By the synergistic effect of ultrasound-driven piezodynamic therapy and immuno-regulation, the proposed piezoelectric nanostructured surface can endow Ti implants with highly efficient antibacterial performance in an antibiotic-free, noninvasive, and on-demand manner. 相似文献
150.
Ming Yi Thi Dao Nguyen Huan Liu Yafang Liu Shu Xiong Yan Wang 《Advanced functional materials》2023,33(26):2213471
Membrane decorated with biocides is an effective way to suppress biofilm growth. However, their immediate biocidal effect usually suffers from a significant decline due to the irreversible consumption of the biocides. Here, a smart nanofiltration membrane is reported with rechargeable antibacterial capability that is fabricated by a facile interfacial polymerization via 3-aminophenylboronic acid and trimesoyl chloride on a polysulfone substrate. Biocides bearing diol groups can be grafted onto the membrane surface under neutral/alkaline condition and then released from the surface under acidic environment, due to the pH-responsive feature of boronate ester complexes. The resultant membrane exhibits integrated properties of fast bacterial inactivating efficiency, rechargeable antibacterial capability, and impressive stability. In addition, the achieved membrane shows remarkable separation efficiency to dye/monovalent salt system. The successful fabrication of the membrane with rechargeable anti-bacterial property provides new insights into the development of pH-responsive and sustainable antibacterial membranes. 相似文献