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441.
442.
Shayan A. Tabrizi Azadeh Shakery Hamed Zamani Mohammad Ali Tavallaei 《Information processing & management》2018,54(4):630-656
Despite the importance of personalization in information retrieval, there is a big lack of standard datasets and methodologies for evaluating personalized information retrieval (PIR) systems, due to the costly process of producing such datasets. Subsequently, a group of evaluation frameworks (EFs) have been proposed that use surrogates of the PIR evaluation problem, instead of addressing it directly, to make PIR evaluation more feasible. We call this group of EFs, indirect evaluation frameworks. Indirect frameworks are designed to be more flexible than the classic (direct) ones and much cheaper to be employed. However, since there are many different settings and methods for PIR, e.g., social-network-based vs. profile-based PIR, and each needs some special kind of data to do the personalization based on, not all the evaluation frameworks are applicable to all the PIR methods. In this paper, we first review and categorize the frameworks that have already been introduced for evaluating PIR. We further propose a novel indirect EF based on citation networks (called PERSON), which allows repeatable, large-scale, and low-cost PIR experiments. It is also more information-rich compared to the existing EFs and can be employed in many different scenarios. The fundamental idea behind PERSON is that in each document (paper) d, the cited documents are generally related to d from the perspective of d’s author(s). To investigate the effectiveness of the proposed EF, we use a large collection of scientific papers. We conduct several sets of experiments and demonstrate that PERSON is a reliable and valid EF. In the experiments, we show that PERSON is consistent with the traditional Cranfield-based evaluation in comparing non-personalized IR methods. In addition, we show that PERSON can correctly capture the improvements made by personalization. We also demonstrate that its results are highly correlated with those of another salient EF. Our experiments on some issues about the validity of PERSON also show its validity. It is also shown that PERSON is robust w.r.t. its parameter settings. 相似文献
443.
Seyed Javad Mirabedini Mohammad Teshnehlab M. H. Shenasa Ali Movaghar Amir Masoud Rahmani 《浙江大学学报(A卷英文版)》2008,9(12):1666-1675
We propose a novel approach called adaptive fuzzy ant-based routing (AFAR), where a group of intelligent agents (or ants) builds paths between a pair of nodes, exploring the network concurrently and exchanging obtained information to update the routing tables. Routing decisions can be made by the fuzzy logic technique based on local information about the current network state and the knowledge constructed by a previous set of behaviors of other agents. The fuzzy logic technique allows multiple constraints such as path delay and path utilization to be considered in a simple and intuitive way. Simulation tests show that AFAR outperforms OSPF, AntNet and ASR, three of the currently most important state-of-the-art algorithms, in terms of end-to-end delay, packet delivery, and packet drop ratio. AFAR is a promising alternative for routing of data in next generation networks. 相似文献
444.
Turki Alquraini Ali Al-Odaib Hesham Al-Dhalaan Haniah Merza 《International Journal of Disability, Development & Education》2019,66(3):233-248
ABSTRACTThis investigation examined the consequences and effects of the severity of mothers psychosocial functioning as assessed by measures parenting stress and depression in a randomised control trial of a Relationship-based Intervention (RBI) called Responsive Teaching (RT). The sample included 28 parents and preschool aged children with Autism from Saudi Arabia. RT subjects received weekly parent–child intervention sessions for 4 months. Dependent variables were mothers’ style of interaction as assessed by the PICCOLO at post intervention as well as pre- and post-measures of parenting stress and depression. There were three findings from this study. First, mothers who participated in this study had extremely high levels of psychosocial dysfunction. Nearly all reported clinical levels of parenting stress and more than 40% reported clinical levels of depressive symptoms. Second, high levels of psychosocial dysfunction did not prevent mothers from participating in RT as indicated by their ability to integrate RT strategies into their interactions with their children. Third, RT was associated with substantial improvements in mother’s parenting stress and depression. Implication for early intervention practice are discussed. 相似文献
445.
Takbir Ali 《Teacher Development》2018,22(1):78-104
This study documented in detail teachers’ voices about their working conditions, professional development needs and opportunities to cater to these needs. The study reported in this paper was conducted as part of a large-scale study that used mixed methods to assess teachers’ professional development needs. The qualitative data reported in this paper were collected using focus group discussion with teachers (N = 481), classroom observation (N = 66), post-observation interviews with teachers (N = 24) and analysis of qualitative responses from survey questionnaires (N = 200). By bringing together a collection of teachers’ voices, the findings of the study illuminate a hope for positive change in teaching and learning in public schools in Khyber Pakhtunkhwa, provided that teachers are genuinely considered as part of the solution and are facilitated with necessary physical and structural resources and psychological incentives. The education system needs to create conditions in schools that support teachers’ work and their continued professional growth. 相似文献
446.
The primary purpose of this study was to investigate the combined and partial effects of the Integrated Reading/Study Strategy
and Conceptual Physics Approach on ninth grade private high school students’ achievement in and attitudes toward optics. The
Integrated Reading/Study Strategy is a new strategy which was developed by integrating previously existing reading strategies
of the KWL and SQ3R with classroom lecturing. The Conceptual Physics Approach is an instructional strategy developed on the
basis of Conceptual Physics suggested by Paul G. Hewitt. To investigate the partial and combined effects of methods, factorial
design was used. The study was conducted with 124 students from two private high schools in the ?ankaya district region of
Ankara, Turkey. Various teaching/learning materials were developed and used for the study. Two measuring tools, Achievement
Test about Optics and Attitude Scale about Optics were used as pre and post tests before and after instruction. The study
continued for a two-month treatment period. The results of the study showed that the combined effect of the Integrated Reading/Study
Strategy and Conceptual Physics Approach improved students’ achievement significantly compared to the separate individual
methods. Although the product of the Integrated Reading/Study Strategy and Conceptual Physics Approach increased students’
attitudes more compared to the remaining methods, the result is not statistically significant. 相似文献
447.
Zhenwei Liu Ali Saberi Anton A. Stoorvogel Donya Nojavanzadeh 《Journal of The Franklin Institute》2021,358(9):4864-4882
In this paper, we design scale-free collaborative protocols for state and regulated state synchronization of homogeneous multi-agent systems (MAS) with arbitrary fast convergence. The protocol design solely depends on the knowledge of the agents’ model and does not require any information about the communication network and the number of agents. Moreover, our protocols can achieve synchronization with any desired convergence rate by simply tuning a design parameter. 相似文献
448.
A novel technique for optimal placement of piezoelectric actuators on smart structures 总被引:3,自引:0,他引:3
The problem of positioning of actuators and sensors on smart materials has been a point of interest in recent years. This is due to the fact that in many practical applications there are limitations in space, weight, etc. of the smart structures, which make the problem of positioning more complex. In addition, it is required that the actuators/sensors have the best possible performance. The development of smart structures technology in recent years has provided numerous opportunities for vibration control applications. The use of piezoelectric ceramics or polymers has shown great promise in the development of this technology. The employment of piezoelectric material as actuators in vibration control is beneficial because these actuators only excite the elastic modes of the structures without exciting the rigid-body modes. This is important since very often only elastic motions of the structures are needed to be controlled. The purpose of this paper is to introduce a novel approach developed for optimizing the location of piezoelectric actuators for vibration suppression of flexible structures. A flexible fin with bonded piezoelectric actuators is considered in this study. The frequency response function (FRF) of the system is then recorded and maximization of the FRF peaks is considered as the objective function of the optimization algorithm to find the optimal placement of the piezoelectric actuators on the smart fin. Three multi-layer perceptron neural networks are employed to perform surface fitting to the discrete data generated by the finite element method (FEM). Invasive weed optimization (IWO), a novel numerical stochastic optimization algorithm, is then employed to maximize the weighted summation of FRF peaks. Results indicate an accurate surface fitting for the FRF peak data and an optimal placement of the piezoelectric actuators for vibration suppression is achieved. 相似文献
449.
Wongphaka Wongrat Ali Elkamel Peter L. Douglas Ali Lohi 《Journal of The Franklin Institute》2011,348(7):1318-1338
Rice drying synthesis is an essential operation that has to be done carefully and cost-effectively. Rice is harvested at high moisture content and hence must be dried within 24 h for safe storage. However, improper drying can cause fissuring in the rice grain, and thus greatly reduce its market value. Multi-pass drying systems are therefore used to gradually bring moisture content to desired level.The problem of rice synthesis, considered in this study, seeks the configuration of units and their corresponding operating conditions that maximize rice quality. This problem is formulated as a mixed-integer dynamic optimization problem. The integer part of the problem reflects process alternatives while the dynamic part originates from nonlinear differential-algebraic equations describing the drying behavior of a rice grain.Clearly such a formidable problem is not easy to solve. Hence, we propose an approach that makes use of two algorithms: a genetic algorithm to search for the best configuration of units and a control vector parameterization approach that optimizes the operating conditions for each configuration. We demonstrate the effectiveness of the approach on a case study. 相似文献
450.
Simin Sohrabi Azim Akbarzadeh Dariush Norouzian Ali Farhangi Mehri Mortazavi Mohammad Reza Mehrabi Mohsen Chiani Zahra Saffari Soheil Ghassemi 《Indian journal of clinical biochemistry : IJCB》2011,26(4):354-359
The attempt is made to produce recombinant factor VIII but the first step in producing such product is production and purification
of rabbit’s polyclonal antibody against factor VIII. The second and third steps involve monoclonal antibody and recombinant
factor VIII production. Factor VIII is one of the most important coagulating factor where its deficiency leads to diseases
like hemophilia type A or classic. It is an inherited disease. Previously, it was obtained through fractionation of blood
plasma of blood donors. After processing, factor VIII could be used to manage such patients. Due to transfer of viral disease
like hepatitis and HIV through factor VIII obtained by fractionation, high cost of production, insufficiency of the donors
and the process of virus removal, thus production of factor VIII through recombinant technology can be useful and helpful.
The reaction between antibody and antigen is one the most specific reaction; therefore, such reaction can be employed to identify
factor VIII. Thereby, rabbits were injected several times with adjuvant-linked antigen to produce antibody. The antibody was
separated from the blood sample, purified and used to identify factor VIII in the research. 相似文献