Chattering-free full-order recursive sliding mode control for finite-time attitude synchronization of rigid spacecraft     

Zhuoyue Song  Chao Duan  Jianan Wang  Qinghe Wu 《Journal of The Franklin Institute》2019,356(2):998-1020

This paper investigates a quaternion-based finite-time cooperative attitude synchronization and tracking of multiple rigid spacecraft with a virtual leader subject to bounded external disturbances. Firstly, the communication network between followers is assumed to be an undirected graph and every follower can get a direct access to the virtual leader, by using two neighborhood attitude error signals, a novel chattering-free recursive full-order sliding mode control algorithm is proposed such that all follower spacecraft synchronize to the virtual leader in finite time. In the proposed algorithm, the sliding mode surface is constructed by two layers of sliding mode surfaces, which are called as the outer and the inner sliding mode surfaces. To achieve finite-time performance of sliding mode dynamics, the outer sliding mode surface is designed as a terminal sliding mode manifold, and the inner one is designed as a fast nonsingular terminal sliding mode manifold, respectively. Then, to reduce the heavy communication burden, a distributed recursive full-order sliding mode control law is designed by introducing a distributed finite-time sliding mode estimator such that only a subset of the group members has access to the virtual leader. Finally, a numerical example is illustrated to demonstrate the validity of the proposed results.  相似文献   

Gradient based approach for generalized discrete-time periodic coupled Sylvester matrix equations     

Lingling Lv  Zhe Zhang  Lei Zhang  Xianxing Liu 《Journal of The Franklin Institute》2018,355(15):7691-7705

The paper is dedicated to solving the generalized periodic discrete-time coupled Sylvester matrix equation, which is frequently encountered in control theory and applied mathematics. The solvable condition and a iterative algorithm for this equation are presented. The proposed method is developed from a point of least squares method. The rationality of the method is testified by theoretical analysis, which shows that the algorithm can solve the problem within finite number of iterations. The presented approach is numerically reliable and requires less computation. A numerical example illustrates the effectiveness of the raised result.  相似文献   

The Buddhist Institute at Phnom Penh,the International Council of Women,and the Rome International Institute for Educational Cinematography: intersections of internationalism and imperialism, 1931–1934     

Joyce Goodman 《History of education》2018,47(3):415-431

This article explores the intersection of aspects of imperialism and internationalism in discussion of cinematography at the League of Nations, at the International Council of Women (ICW), and as they played out in the imperial, national and local flows around educational cinematography in the work of Suzanne Karpelès at the Institute of Buddhist Studies in Phnom Penh, Cambodia. It focuses on the 1931 ICW cinematograph conference organised by Laura Dreyfus-Barney at the League’s Rome International Institute for Educational Cinematography (IIEC) and on the IIEC’s 1934 cinematography congress, when Dreyfus-Barney fed Karpelès’ ideas about educational film into the congress. The article looks at the notion of rapprochement (of nations) within internationalism as this became articulated at both the League and the ICW with notions about mentalities within imperialism. It also traces the intersection of rapprochement and mentalities in Karpelès’ promotion of educational cinematography from her base in Phnom Penh. The article concludes that various elements around the cinematic at the League, the ICW and at Phnom Penh illustrate articulations of internationalism in the domains of nationalism and imperialism as well as articulations of the national and imperial in the domain of the international.  相似文献   

Psychological responses to reservation-based discrimination: A qualitative study of socially marginalized youth at a premier Indian university     

《International Journal of Educational Development》2020

Given the history of caste politics in India, it is not surprising that the socially marginalized students face discrimination, especially after the introduction of the reservation policy (affirmative action) in educational institutes. Our qualitative study, informed by Meyer’s Minority Stress model, analysed in-depth interviews with 30 undergraduate students, 3 faculty members, and 4 administrative officials at a premier Indian university to examine the psychological wellbeing of the reserved category students. We analysed how the discrimination processes contributed to students’ poor academic performance, low self-esteem, and weak motivation. Student group affiliations and university resources created a supportive environment for the socially marginalized, despite a small risk of stigmatization due to enrolment in a few campus support-programs. Moreover, there existed a palpable frustration among the socially privileged students, resulting in discriminatory attitudes against reserved categories but not “lower” caste. Our findings call for the attention of college administrators, policymakers, and the society at large to ensure that well-intended social justice policies are efficiently implemented, to deliver justice to the underprivileged students of India.  相似文献   

大型科研院所的综合竞争力评价研究   总被引：4，自引：0，他引：4       下载免费PDF全文

柴国荣  徐渝  董书宁 《科研管理》2006,27(3):110-115

大型科研院所的竞争环境在转制后发生了质的变化,如何科学评价其综合竞争力具有重要的理论意义和实践价值。本文构建了大型科研院所的竞争力评价指标体系,设计了兼顾"功能性"和"协调性"的综合性评价方法,最后运用于煤炭科学研究总院下辖某分院的综合竞争力评价,并根据评价结果对其市场竞争态势进行了分析。  相似文献   

孔子的师德思想管见     

张运霞 《培训与研究》2006,23(3):27-29

孔子是我国历史上第一位提出教师职业道德要求的人。他不仅提出了师德要求,而且还进行了多方面的论述和概括,从而形成了中国教育史上第一个教师职业道德的规范体系。其师德思想内涵丰富,主要表现在以下四点:热爱学生,有教无类;因材施教,循循善诱;学而不厌,诲人不倦;以身作则、为人师表。  相似文献   

对孔子“君君臣臣”思想的再审视     

梁振杰 《云南师范大学学报(哲学社会科学版)》2006,38(2):69-74

“君君，臣臣，父父，子子”是孔子“正名”思想的重要表述。考察孔子原意主要是针对统治者而言的，要求君要行“君道”，强调的重点在“君”一方。今天所说的“君臣、父子、夫妇”尊卑等级思想并非孔子思想的本来面貌，是后儒对孔子思想的过度阐释，是对孔子思想的偏离和歪曲。  相似文献   

"仁"与"法":比较法视角的孔子和亚里斯多德     

祁建平 《哈尔滨学院学报》2006,27(10):52-55

孔子和亚里斯多德是古代中国和西方两位杰出的思想家。他们的法律思想分别在中国和西方法律思想史上占有重要地位,对他们的法律思想进行比较研究,可以给我们以许多有益的启示。文章对生活在同一历史时期的中西方两位伟大的思想家———孔子和亚里斯多德的法律思想从政治倾向性、方法论基础、正义观、伦理基础、“人治”和“法治”论等五个方面进行了比较研究。  相似文献   

孔门弟子未仕原因探析     

褚为强 《南宁师范高等专科学校学报》2006,23(3):18-20

孔门弟子一向积极用世,崇尚“学而优则仕”。然而,事实上,孔门中也有很多弟子未曾出仕。如颜回、闵子蹇、原宪、公析哀、子夏、子羔、子我等。主要原因是,当时社会政治秩序混乱,不利于或不适合出仕,加之各人个性上的特点,有好几位弟子主动选择了不出仕。另外,孔子本人考虑到几位弟子的个性特点,反对他们出仕。  相似文献   

《韩诗外传》与《论语》异同浅议     

张岩 《大连大学学报》2004,25(5):27-28

从《韩诗外传》与《论语》相比较的角度,剖析《韩诗外传》内容和形式上的一些特点,及其与《论语》的传承关系,浅析其相同与不同,并进而肯定了《韩诗外传》的价值。  相似文献