Observer based leader-following consensus of second-order multi-agent systems with nonuniform sampled position data     

Syed Ali Ajwad  Tomas Ménard  Emmanuel Moulay  Michael Defoort  Patrick Coirault 《Journal of The Franklin Institute》2019,356(16):10031-10057

This paper deals with the leader-following consensus problem of multi-agent systems with the consideration that each agent can only transmit its position state to the neighbors at irregular discrete sampling times. In the proposed algorithm, a continuous-discrete time observer is designed for the continuous estimation of both position and velocity from the discrete position information of the neighbors. These estimated states are then used for designing a continuous control law which solves the leader-following consensus problem. Moreover, the dynamics of the leader is not fixed and can be controlled through an external input. The stability analysis has been carried out by employing the Lyapunov approach which provides sufficient conditions to tune the parameters according to the maximum allowable sampling period. The developed algorithm has been simulated and then tested on an actual multi-robot system consisting of three differential drive wheeled robots. Both simulation and hardware results validate the effectiveness of the control algorithm.  相似文献   

Profile and Motivations of Registered Whole-Body Donors in Turkey: Istanbul University Experience     

İlke Ali Gürses  Ahmet Ertaş  Başak Gürtekin  Osman Coşkun  Mehmet Üzel  Özcan Gayretli  Mehmet Selman Demirci 《Anatomical sciences education》2019,12(4):370-385

Little is known regarding the profiles of whole body donors in Muslim majority countries where donation is scarce. Therefore, this study aims to profile registered donors in Turkey by means of a survey. The explored data could be used to improve ongoing campaign efforts and ethical practices such as commemoration services. Registered donors of the donation programs at the two faculties of medicine of Istanbul University were compared with the national population and a cluster analysis was performed to reveal any concealed sub-groups. Data from 188 respondents were analyzed. The majority of registered donors were married (42%), male (65.4%), aged over 50 years (76%), held a tertiary education degree (49.7%), and were irreligious (58.5%). Cluster analysis revealed two groups with significantly different educational levels, marital statuses, and religious choices. Regarding whether their bodies could be used for education or research, the majority (64.5%) of the respondents left the decision to the anatomy department. Similarly, 73.8% approved indefinite use of their organs, body parts and/or skeletons. The respondents were also willing to share their medical history (94.2%) and personal information (81.6%) if needed. Motivational themes for body donation including usefulness, impermanence, religion, awareness, and kinship were devised after a thematic analysis. Among the respondents, 56.5% were registered organ donors and 63.3% were frequent blood donors. The results of this study provide data that may help revising informed consent forms, developing and implementing thanksgiving ceremonies, and selecting additional targets for supporting body donation campaign activities such as organ and blood donation units.  相似文献   

Neural embedding-based indices for semantic search     

Fatemeh Lashkari  Ebrahim Bagheri  Ali A. Ghorbani 《Information processing & management》2019,56(3):733-755

Traditional information retrieval techniques that primarily rely on keyword-based linking of the query and document spaces face challenges such as the vocabulary mismatch problem where relevant documents to a given query might not be retrieved simply due to the use of different terminology for describing the same concepts. As such, semantic search techniques aim to address such limitations of keyword-based retrieval models by incorporating semantic information from standard knowledge bases such as Freebase and DBpedia. The literature has already shown that while the sole consideration of semantic information might not lead to improved retrieval performance over keyword-based search, their consideration enables the retrieval of a set of relevant documents that cannot be retrieved by keyword-based methods. As such, building indices that store and provide access to semantic information during the retrieval process is important. While the process for building and querying keyword-based indices is quite well understood, the incorporation of semantic information within search indices is still an open challenge. Existing work have proposed to build one unified index encompassing both textual and semantic information or to build separate yet integrated indices for each information type but they face limitations such as increased query process time. In this paper, we propose to use neural embeddings-based representations of term, semantic entity, semantic type and documents within the same embedding space to facilitate the development of a unified search index that would consist of these four information types. We perform experiments on standard and widely used document collections including Clueweb09-B and Robust04 to evaluate our proposed indexing strategy from both effectiveness and efficiency perspectives. Based on our experiments, we find that when neural embeddings are used to build inverted indices; hence relaxing the requirement to explicitly observe the posting list key in the indexed document: (a) retrieval efficiency will increase compared to a standard inverted index, hence reduces the index size and query processing time, and (b) while retrieval efficiency, which is the main objective of an efficient indexing mechanism improves using our proposed method, retrieval effectiveness also retains competitive performance compared to the baseline in terms of retrieving a reasonable number of relevant documents from the indexed corpus.  相似文献   

The perspective of six Malaysian students on playing video games： Beneficial or detrimental？   总被引：1，自引：0，他引：1  

Roselan Baki Eow Yee Leng Wan Zah Wan Ali Rosnaini Mahmud Mohd. Sahandri Gani Hamzah 《美中教育评论》2008,5(11):11-21

This study provides a glimpse into understanding the potential benefits as well as harm of playing video games from the perspective of six Malaysian secondary school students, aged 16-17 years old. The rationale of the study is to enable parents, educators, administrators and policy makers to develop a sound understanding on the impact of playing video games before making any judgment on the contemporary youth culture. Thus, further decision on the acceptance of video games as a new innovation in school or at home could be considered. Although this study is not very extensive, the findings suggest that playing video games contributes to cognitive, social, motivational and emotional development. However, potential harms do exist. Parents play an important role in guiding their children either directly or indirectly, as indicated by the respective students. Caution is advised in the interpretation of the study＇s findings as it is solely based on the perspectives of the students, as the first person＇s views. Nevertheless, each student has their very own perspective on the impact of video games on them.  相似文献   

全流通后我国上市公司筹资方式新视野     

周阿立  王华春 《广东技术师范学院学报》2008,(8)

从十多年证券市场的发展历程来看,股权筹资处于主导地位,而债权筹资不足.近几年衍生金融工具筹资有了一些新的发展,如可转债、权证、资产支持证券等,为上市公司筹资提供了更多可供选择的筹资渠道体系.2000年以后股权筹资金额逐年下降,债权筹资逐年上升,资本结构逐步趋于合理.全流通后,上市公司的筹资市场环境将发生巨大的变化,企业的筹资成本与风险也会发生很大的变化,股权筹资稀释控制权的后果将会显现出来,负债筹资的优势也会更加明显.上市公司应充分利用不同筹资工具的优势和特色,降低企业的资金成本和筹资风险,优化资本结构.  相似文献   

团学活动在高职生关键能力培养中的拓展作用   总被引：1，自引：0，他引：1  

吴阿莉 《石家庄铁路职业技术学院学报》2008,7(3)

在比较、分析关键能力内涵的基础上,指出应很好地重视和发挥团学活动在高职生关键能力培养中作用,并结合实际提出通过团学活动培养和提高高职生关键能力应遵循的四条原则。  相似文献   

Pursuing higher education: adaptation challenges and coping strategies of rural students at urban universities in Bangladesh     

Ali  Shoukot  Sarker  Md Fouad Hossain  Islam  M. Saiful  Islam  Md Kabirul  Al Mahmud  Rafi 《Tertiary Education and Management》2021,27(2):91-106

Tertiary Education and Management - This study examines how students from rural areas in Bangladesh face particular challenges in adapting to university dormitories in urban areas. There has been...  相似文献   

The effects of function-based communication intervention for a student with emotional disturbance in a general education setting     

Celal Perihan  Ali Bicer 《Journal of Research in Special Educational Needs》2021,21(2):63-72

Research has shown that most children with emotional disturbance (ED) are struggling to use communication skills and they may tend to use inappropriate behaviours as a form of communication to disclose their needs. A function-based communication intervention might be an effective approach to decrease inappropriate behaviours of children with ED. The purpose of this single-case multiple baseline reversal design (ABAB) study was to examine the effectiveness of the function-based communication intervention for on-task and disruptive behaviours of an 8-year-old student with ED. Functional behavioural assessment (FBA) was conducted and based on the findings of FBA, a colour-coded communication system, was implemented during reading and math classes. The findings indicated that function-based communication intervention was effective in increasing on-task as well as decreasing disruptive behaviours. Furthermore, the function-based communication intervention improved communication between the teacher and the student that resulted in decreasing disruptive behaviours in a general classroom setting. The generalisability of the findings due to the limited number of participants was an important limitation for this study. Future directions, as well as implications for practices, are discussed.  相似文献   

Creating Connections: Using a Narrative Approach in Career Group Counseling With College Students From Diverse Cultural Backgrounds     

Mary Ann Clark  Lisa Severy  Shanaz Ali Sawyer 《Journal of College Counseling》2004,7(1):24-31

Changes in the world of work as well as demographic shifts toward a more diverse college population and workforce require changes in the way career counseling is provided on college campuses. The authors propose using a narrative group counseling approach to serve college and university students from various cultural backgrounds. Through this approach, students develop their own career/life stories, incorporating their cultural values, family and community considerations, and life roles.  相似文献   

The tortoise and the hare enigma in e-transformation in Japanese and Korean higher education     

Colin Latchem  Insung Jung  Kumiko Aoki  Ali Ekrem Ozkul 《British journal of educational technology : journal of the Council for Educational Technology》2008,39(4):610-630

Japan and Korea have highly developed information and communications technology infrastructures and have recently reformed their higher education systems and encouraged e-transformation. However, Japanese universities have not embraced e-learning as wholeheartedly as their Korean counterparts. The paper concludes that this is due to governmental and institutional failure to develop a cogent vision and strategic plan for e-learning, to recognise the need for fundamental shifts in organisational cultures and structures and pedagogy and to provide training, funding, recognition and reward for such development. It attributes this to differences in the cultural perspectives, values and customs of the two countries' policy makers, managers and faculty members. The findings are seen to hold important lessons for other countries embarking on e-transformation.  相似文献