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排序方式: 共有274条查询结果,搜索用时 15 毫秒
1.
该文对高校科研管理工作进行了详细分析,结合高职院科研工作的特点,设计并开发了基于C/S和B/S混合模式的科研管理信息系统,该系统从某高职院科研管理工作的业务流程和教职工的实际需要出发,设计了相应的功能模块和操作流程,应用了正则表达式技术直接从“知网”提取教职工论文发表信息,节省了数据录入时间. 该系统投入运行近两年,使用结果表明,该科研管理系统使科研管理工作更加规范,工作效率大大提高.  相似文献   
2.
In this study, biomimetic sodium alginate (SA)/silk fibroin (SF) scaffolds were successfully fabricated by supercritical CO2 technology. The SA/SF scaffolds exhibited an interconnected porous and extracellular matrix (ECM)-like nanofibrous structures. Moreover, the SA microparticles were embedded in the SF scaffolds. Increasing the content of SA microparticles could improve tensile strength and compressive strength of the SF scaffolds and reduce the porosity of the SF scaffolds. The addition of the SA microparticles could also regulate the degradation rate of the SA/SF scaffolds. Furthermore, the results of in vitro biocompatibility evaluation, indicated that the SA/SF scaffolds exhibited no obvious cytotoxicity and higher cell adhesion ability and were more favorable for L929 fibroblasts proliferation than pure SF scaffolds. Therefore, the SA/SF scaffolds with ECM-like nanofibrous and interconnected porous structure have potential application in skin tissue engineering.  相似文献   
3.
基于正交实验设计的人工蜂群算法   总被引:1,自引:0,他引:1  
周新宇  吴志健  王明文 《软件学报》2015,26(9):2167-2190
人工蜂群算法是近年来提出的较为新颖的全局优化算法,已成功地应用于解决不同类型的实际优化问题.然而在该算法及相关的改进算法中,侦察蜂通常采用随机初始化的方法来生成新食物源.虽然这种方法较为简单,但易造成侦察蜂搜索经验的丢失.从算法搜索过程的内在机制出发,提出采用正交实验设计的方式来生成新的食物源,使得侦察蜂能够同时保存被放弃的食物源和全局最优解在不同维度上的有益信息,提高算法的搜索效率.在16个典型的测试函数上进行了一系列实验验证,实验结果表明:1) 该方法能够在基本不增加算法运行时间的情况下,显著地提高人工蜂群算法的求解精度和收敛速度;2) 与3种典型的变异方法相比,有更好的整体性能;3) 可作为提高其他改进人工蜂群算法性能的通用框架,具备有良好的普适性.  相似文献   
4.
More and more complicated conceptual design of ship’s engine room (CDSER) heavily depends on designers’ engineering knowledge and existing ship data. To achieve intelligent design at the initial ship design stage, many researchers have made much significant progress in this field, however, most of them only focused on how to find the similar constructed ships. At present, how to utilize these existing data remains an untouched topic. In order to make good use of the existing data and reduce the dependence on designers’ experience, a novel system named Expert System for Aided Conceptual Design of Ship’s Engine Room Automation (ESACD), is elaborated in this study. With the support of the constructed Ship Data Warehouse System, two core subsystems Configuration Selection Assistant (CSA) and Design Scheme Decision Assistant (DSDA) are included in ESACD. A promising approach integrating Fuzzy c-means algorithm (FCM) and Rough Sets Theory (RST) to extract configuration rules from the stored data is adopted in CSA. According to engineers’ proposals, RST is utilized to reason knowledge in incomplete scheme information systems for getting design scheme rules in DSDA, which are useful suggestions for engineers to get better schemes at this stage. Finally, the validity and necessity of this interactive expert system are demonstrated through the CDSER of a new 50,000 DWT Handymax bulk carrier. It is proved that ESACD can efficiently facilitate rapid and intelligent design in CDSER, and reduce the cost of a new ship design.  相似文献   
5.
该文提出了一种基于非线性预处理网络流量预测方法NLPP(Non-Linear Preprocessing Network Traffic Prediction)的分布式拒绝服务DDoS攻击检测算法,该算法是在分析DDoS攻击的网络流量特性基础上提出的,由一个基本检测算法和一个非线性预处理网络流量预测方法组成.通过与两种...  相似文献   
6.
为解决多阈值图像分割中分割区域数较难确定的问题,提出一种基于可逆跳跃马尔可夫链蒙特卡罗(RJMCMC)的自适应多阈值图像分割方法.基于图像直方图的多阈值分割的本质是寻找直方图各峰间的谷底,但其个数较难确定且各局部峰并非都是高斯分布.因此文中用更具普适性的混合α稳定分布拟合直方图,建立包含局部峰个数及各分布元参数的分层贝叶斯概率模型.采用RJMCMC后验概率推理自适应确定混合α稳定分布的分布元个数及各自参数,从而获得分割区域数和多阈值参数.针对单晶炉拉晶图像、人脑核磁共振图像及国际标准测试图进行测试,结果表明该方法准确地建立图像分割模型,得到满意的多阈值分割结果.  相似文献   
7.
摘要:目的 采用电感耦合等离子体质谱法(ICP-MS)测定辣椒中镉(Cd)含量,及评估测定过程产生的不确定度,以提高定量分析结果的可靠性。方法 建立数学模型,分析识别试样称量、试样定容、标准物质、标准溶液的配制、标准曲线的拟合、重复测量、回收试验等不确定度来源,量化各不确定度分量,计算合成标准不确定度。结果 辣椒中镉含量不确定度测定结果为:。结论 测定过程不确定度主要来源于标准溶液配制和标准曲线拟合。电感耦合等离子体质谱法测定辣椒中镉含量准确度高,重复性好,建立的不确定度评估能保证分析结果的质量。  相似文献   
8.
目的筛选对拟穴青蟹过敏原原肌球蛋白(tropomyosin,TM)抗原表位具有特异性结合能力的适配体小肽,并鉴定适配体小肽对TM的免疫结合活性的抑制作用。方法采用ExPASy peptide cutter软件预测TM分子中胰蛋白酶酶切位点,结合TM线性表位设计反义小肽,经AutoDock 4.0软件模拟分子对接,筛选得到适配体小肽。采用抑制性ELISA的方法,检测筛选的适配体小肽对TM与特异性IgG抗体结合活性的抑制作用。结果 TM氨基酸序列中有25个胰蛋白酶酶切位点,设计TM的31条反义小肽,利用分子对接筛选得到12个适配体小肽。抑制性ELISA结果显示,12条适配体小肽均能明显抑制TM与IgG抗体的特异性结合,其中适配体小肽5抑制能力最强,其抑制率为36.2%。结论通过分子对接筛选得到能明显抑制TM免疫结合活性的适配体小肽,为降低TM致敏性的研究提供理论参考。  相似文献   
9.
In this article, based on partial differential equations (PDEs), the flexible manipulator system with both dead-zone input and state constraints is studied. The dynamic model of the flexible manipulator system is described by PDEs. The parameters of the dead-zone input are unknown, and the state constraint problem is also considered. An adaptive approach is proposed to offset the effects caused by dead-zone input. Thus, to guarantee that all states remain within their respective constraint regions, the boundary control law based on the barrier Lyapunov function is given, and an adaptive controller is designed. According to the Lyapunov analysis method, the control method is given to ensure that all signals of the closed-loop system are bounded and all states satisfy the constraint conditions. Finally, simulation results show the effectiveness of the proposed control method in this article.  相似文献   
10.
Hu  Li-Bin  Huang  Xin-Yu  Zhang  Shan  Chen  Xue  Dong  Xian-Hui  Jin  He  Jiang  Zhen-Yu  Gong  Xiao-Ran  Xie  Yi-Xuan  Li  Chen  Chi  Zong-Tao  Xie  Wan-Feng 《Journal of Materials Science: Materials in Electronics》2021,32(19):23728-23736

Morphology transformation and crystal growth strategies of metal oxide semiconductors are still extensively studied in material science recently, because the morphology and crystallinity significantly affect the physicochemical characteristics of metal oxide nanomaterials. However, understanding the morphology changes of α-MoO3 induced by annealing is still a challenge. Herein, the nanostructure transition of α-MoO3 induced by the annealing temperature is carefully investigated via the XRD and SEM methods. It can be found that crystallization is highly dependent on the annealing temperature. Interestingly, the MoO3 nanoflowers can change into nanosheets at 500 °C. Afterward, the nanosheets turned into microrods with the increase in annealing temperature due to the continuous growth of MoO3 crystal. On the other hand, the sensing performances of various MoO3 nanostructures are studied toward ethanol gas. Compared to the MoO3 nanoflowers and microrods, the MoO3 nanosheets-based sensor exhibits superior sensing performance to ethanol, and the maximum response value is 8.06.

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