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41.
42.
无人机空中加油控制精度问题,无人受油机模型的各种不确定性与来自外部的各种干扰归结为扰动,造成控制精度差。为解决上述问题,提出一种免疫粒子群优化算法的自抗扰无人机自主空中加油飞行控制律设计方法。利用自抗扰控制能够自动检测并补偿内部与外部干扰影响的特点,并利用扩张状态观测器进行估计与补偿,从而增强了所设计飞行控制律的鲁棒性,用免疫粒子群优化算法对自抗扰控制器参数进行了优化研究,以提高设计效率。仿真结果表明,所设计的自抗扰自主空中加油控制系统具有优良的控制性能与较高的控制精度,能够满足无人机自主空中加油的要求。  相似文献   
43.
免疫遗传算法在烧结矿配料优化中的应用   总被引:4,自引:0,他引:4  
李智  姚驻斌 《上海金属》2004,26(6):23-28
运用免疫遗传算法和MATLAB语言 ,编制了钢铁烧结矿配料优化计算仿真程序 ,计算机仿真结果表明符合实际生产工艺要求 ,可直接应用于生产 ,提高各种烧结矿的综合利用率 ,降低成本 1 0 32 %。从而证明了免疫遗传算法是一种切实有效的优化方法 ,该算法为钢铁烧结矿配料问题的优化求解提供了新的思路和方法。  相似文献   
44.
Assessment of Manufacturing Operational Complexity   总被引:2,自引:0,他引:2  
The manufacturing system must balance human characteristics, needs, skills and capabilities within the technical and business environment, in order to be effective and successful. A Systems Analysis and Design approach was utilized to integrate manufacturing technologies with the capabilities of human workers, in order to augment the performance of both. A framework was created on which to build systems analysis tools that focus on realistic factors within the manufacturing environment, such as information quantity, diversity and content; complexity (product, process and operational); task effort, and so forth. A matrix methodology and an objective measure of complexity have been developed that assess the three levels of manufacturing complexity: product complexity, process complexity and operational complexity. The focus of this paper is the ‘operational complexity’ and it provides insight into the system performance and sensitivities when considering human characteristics.  相似文献   
45.
聚乙二醇化重组人生长激素的性质及活性   总被引:1,自引:0,他引:1  
目的 研究聚乙二醇化重组人生长激素的性质及活性。方法 通过分子筛高效液相 (SizeexclusionHPLC)、毛细管等电聚焦 (CIEF)、圆二色谱 (CD)以及荧光光谱等方法检测单聚PEG- GH的纯度、等电点、二级结构以及分子构象 ;采用妊娠兔肝细胞放射受体分析法 (RRA)检测单聚PEG GH的体外受体亲和力 ,采用未成年去垂体大鼠体重增加法检测体内生物活性。结果 分子筛高效液相图谱上仅出现一个峰 ,表明样品纯度很高 ,等电点范围为 5 .1~ 5 .2 ,与未修饰的rhGH的等电点相一致 ;CD谱与荧光光谱均表明单个mPEG ALD的修饰对rhGH的二级结构以及分子构象没有明显影响 ;与未修饰的rhGH相比 ,单聚PEG GH体外受体亲和力明显降低 ;但体内作用时间更长 ,且更加有效。结论 此结果为进一步研究和开发长效重组人生长激素提供了理论依据。  相似文献   
46.
采用人胎盘血为原料,利用Sephadex G-200,DEAE-Sephadex A-50层析,Sepharose 4B反相免疫亲和层析技术,获得妊娠相关血浆蛋白A(PAPP-A)纯品,经8.0%聚丙烯酰胺凝胶电泳、免疫电泳、双向免疫扩散证明,所提取的PAPP-A纯品为单一成分。免疫家兔获得抗血清,其效价在1:16以上。  相似文献   
47.
介绍了焦化污水生化处理系统的改造、开工、调试和运行情况.讨论了处理过程中的影响因素、操作管理经验以及污水处理工艺的特点和发展前景。  相似文献   
48.
目的在大肠杆菌中表达重组人白细胞介素-10(Interleukin-10,IL-10),并检测其生物学活性。方法将IL-10基因重组到质粒pET11c中,转化BL21(DE),提取质粒,经酶切鉴定和测序分析;在25℃用低浓度的IPTG诱导表达,对包涵体IL-10稀释复性;经ELISA检测其含量,MC/9细胞增殖法检测其生物学活性。结果工程菌IL-10/pET11c/BL21诱导表达的目的蛋白以可溶性和包涵体两种形式存在,Westernblot鉴定证实为IL-10蛋白,两种形式的IL-10均具有一定的生物学活性。结论已成功地在大肠杆菌中表达了IL-10,为进一步纯化和制备IL-10的基因工程药物打下了基础。  相似文献   
49.
Climate change is forecast to bring more frequent and intense precipitation to New York which has motivated research into the effects of floods on stream ecosystems. Macroinvertebrate assemblages were sampled at 13 sites in the Mohawk River basin during August 2011, and again in October 2011, following historic floods caused by remnants of Hurricane Irene and Tropical Storm Lee. The annual exceedance probabilities of floods at regional flow‐monitoring sites ranged from 0.5 to 0.001. Data from the first 2 surveys, and from additional surveys done during July and October 2014, were assessed to characterize the severity of flood impacts, effect of seasonality, and recovery. Indices of total taxa richness; Ephemeroptera, Plecoptera, and Trichoptera (EPT) richness; Hilsenhoff's biotic index; per cent model affinity; and nutrient biotic index‐phosphorus were combined to calculate New York State Biological Assessment Profile scores. Analysis of variance tests were used to determine if the Biological Assessment Profile, its component metrics, relative abundance, and diversity differed significantly (p ≤ .05) among the four surveys. Only total taxa richness and Shannon–Wiener diversity increased significantly, and abundance decreased significantly, following the floods. No metrics differed significantly between the July and August 2014 surveys which indicates that the differences denoted between the August and October 2011 surveys were caused by the floods. Changes in taxa richness, EPT richness, and diversity were significantly correlated with flood annual exceedance probabilities. This study increased our understanding of the resistance and resilience of benthic macroinvertebrate communities by showing that their assemblages were relatively impervious to extreme floods across the region.  相似文献   
50.
ContextSecurity in Process-Aware Information Systems (PAIS) has gained increased attention in current research and practice. However, a common understanding and agreement on security is still missing. In addition, the proliferation of literature makes it cumbersome to overlook and determine state of the art and further to identify research challenges and gaps. In summary, a comprehensive and systematic overview of state of the art in research and practice in the area of security in PAIS is missing.ObjectiveThis paper investigates research on security in PAIS and aims at establishing a common understanding of terminology in this context. Further it investigates which security controls are currently applied in PAIS.MethodA systematic literature review is conducted in order to classify and define security and security controls in PAIS. From initially 424 papers, we selected in total 275 publications that related to security and PAIS between 1993 and 2012. Furthermore, we analyzed and categorized the papers using a systematic mapping approach which resulted into 5 categories and 12 security controls.ResultsIn literature, security in PAIS often centers on specific (security) aspects such as security policies, security requirements, authorization and access control mechanisms, or inter-organizational scenarios. In addition, we identified 12 security controls in the area of security concepts, authorization and access control, applications, verification, and failure handling in PAIS. Based on the results, open research challenges and gaps are identified and discussed with respect to possible solutions.ConclusionThis survey provides a comprehensive review of current security practice in PAIS and shows that security in PAIS is a challenging interdisciplinary research field that assembles research methods and principles from security and PAIS. We show that state of the art provides a rich set of methods such as access control models but still several open research challenges remain.  相似文献   
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