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1.
Recent research has shown the effectiveness of rich feature representation for tasks in natural language processing (NLP). However, exceedingly large number of features do not always improve classification performance. They may contain redundant information, lead to noisy feature presentations, and also render the learning algorithms intractable. In this paper, we propose a supervised embedding framework that modifies the relative positions between instances to increase the compatibility between the input features and the output labels and meanwhile preserves the local distribution of the original data in the embedded space. The proposed framework attempts to support flexible balance between the preservation of intrinsic geometry and the enhancement of class separability for both interclass and intraclass instances. It takes into account characteristics of linguistic features by using an inner product‐based optimization template. (Dis)similarity features, also known as empirical kernel mapping, is employed to enable computationally tractable processing of extremely high‐dimensional input, and also to handle nonlinearities in embedding generation when necessary. Evaluated on two NLP tasks with six data sets, the proposed framework provides better classification performance than the support vector machine without using any dimensionality reduction technique. It also generates embeddings with better class discriminability as compared to many existing embedding algorithms.  相似文献   

2.
In this paper, we address the relation between Leader‐Member Exchange (LMX; the quality of the relationship between leader and subordinate), employee creativity (the generation of novel and useful ideas), and employee innovation (the promotion and implementation of these ideas). In the current set of studies, we test the competing hypotheses that LMX will either have a direct effect on employee innovation, or an indirect effect through employee creativity. In a field study of leader–subordinate dyads (N = 118), we found that LMX had no direct effect on employee innovation, and that employee creativity fully mediated the relationship between LMX and innovation. In a follow‐up two‐wave field study of employees (N = 398), we found that the LMX dimension professional respect predicted innovation through creativity, while the other dimensions did not. The results of this work indicate that research on LMX and innovation requires a multidimensional perspective, and that it may be valuable to differentiate between creativity and innovation.  相似文献   

3.
High pixel per inch and high‐resolution micro‐LED displays are attracting more and more attentions. The increasing pixel number requires a large amount of bonding pads and brings huge difficulties to micro‐LED system design and lowers power efficiency as well. It is urgent to integrate row and column driving circuits onto the micro‐LED panel. Here, we report a fully integrated active matrix programmable micro‐LED system on panel (SoP) with ultraviolet and blue emission wavelengths. The micro‐LED SoP has a resolution of 60 × 60 and pixel pitch of 70 μm. The micro‐LED SoP was achieved by integrating micro‐LED arrays with silicon‐based p‐channel metal‐oxide semiconductor driving panel using fine‐toned flip‐chip bonding technology. With fully integrated scan and data circuits, the number of bonding pads was greatly reduced from 136 to 28, and large amount of metal interconnection lines were saved. The micro‐LED SoP panel was mounted on a periphery driving board, and representative characters were displayed successfully.  相似文献   

4.
Local search is a paradigm for search and optimization problems, which has recently evidenced to be very effective for a large number of combinatorial problems. Despite the increasing interest of the research community in this subject, there is still a lack of a widely‐accepted software tools for local search. We propose EASY LOCAL , an object‐oriented framework for the design and the analysis of local‐search algorithms. The abstract classes that compose the framework specify and implement the invariant part of the algorithm and are meant to be specialized by concrete classes that supply the problem‐dependent part. The framework provides the full control structures of the algorithms, and the user has only to write the problem‐specific code. Furthermore, the framework comes with some tools that simplify the analysis of the algorithms. The architecture of EASY LOCAL provides a principled modularization for the solution of combinatorial problems by local search and helps the user by deriving a neat conceptual scheme of the application. It also supports the design of combinations of basic techniques and/or neighborhood structures. The framework has been tested in some applicative domains and has proved to be flexible enough in the implementation of algorithms for the solution of various scheduling problems. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

5.
A sense of ‘we‐ness’– enacted through collective identity and culture – is both crucial in online, remote contexts, and particularly difficult to develop in such settings. Using Wittgenstein's concept of language games, we examine how participants of two online forums construct collective identity and culture through their discursive practices. We suggest a strong performative interpretation of the notion of language games, i.e. members of a community produce a sense of we‐ness through their participation in the language game while also defining their expected behaviours and actions. We illustrate how the notion of language games offers an approach for researching and analysing the emergence of collective identity and culture in online forums.  相似文献   

6.
7.
The theory of (n) truth degrees of formulas is proposed in modal logic for the first time. A consistency theorem is obtained which says that the (n) truth degree of a modality-free formula equals the truth degree of the formula in two-valued propositional logic. Variations of (n) truth degrees of formulas w.r.t. n in temporal logic is investigated. Moreover, the theory of (n) similarity degrees among modal formulas is proposed and the (n) modal logic metric space is derived therefrom which contains the classical logic metric space as a subspace. Finally, a kind of approximate reasoning theory is proposed in modal logic. Supported by the National Natural Science Foundation of China (Grant Nos. 10331010 and 10771129), and the Foundation of 211 Construction of Shaanxi Normal University  相似文献   

8.
Abstract— One of the most annoying distortions in (auto)stereoscopic displays is probably cross‐talk, visible as double edges, which is mainly caused by an imperfect separation of left‐ and right‐eye images. For different types of three‐dimensional (3‐D) displays, cross‐talk is caused by different origins, which could result in different levels of perceived image distortion. To evaluate the influence of (auto)stereoscopic display technology on cross‐talk perception, optical measurements and subjective assessments were performed with three different types of 3‐D displays. It is shown with natural still images that the 3‐D display technology with the lowest luminance and contrast level tolerates the highest level of cross‐talk, while still maintaining an acceptable image‐quality level.  相似文献   

9.
Abstract— Electroluminescent near‐infrared (NIR) emitters are of interest in creating special displays for applications such as communications, chemical sensoring, friend‐and‐foe identification, aligning and checking systems that detect NIR radiation, medicine, etc. By performing this research, known NIR emitters (thermal sources, semiconductor diodes and lasers, and solid‐state lasers) were supplemented by NIR‐emitting TFEL devices based on ZnS: Er(F) and ZnS(Se): Cr electron‐beam‐evaporated films. Some characteristics of these devices as NIR emitters are given. There are two narrow intensive bands at 980 and ~1530 nm in the emission spectrum of ZnS: Er(F) TFEL devices. The broadband emission is the range of from 1.8 μm up to 2.7 μm takes place in the ZnS(Se): Cr devices. The wavelength of the peak emission can be varied owing to interference. The mechanism of electroluminescence in the ZnS: Er(F) and ZnS(Se): Cr devices is the direct impact excitation of Er3+ and Cr2+ ions, respectively.  相似文献   

10.
The emergence of so-called free or open-source software and the growth of its economic importance in various industries make questions regarding the legal status of free/open-source licenses especially important. In December 2010, new draft amendments to the Civil Code were published, introducing new concepts in order to reflect the ideas pursued by these types of licenses. This article analyzes existing problems with the legal status of free/open-source licenses, whether proposed amendments may solve them, and what risks they may create. Since Russia is among the first countries trying to include provisions on free/open-source licenses in its legislation, such analysis may be of interest to foreign lawmakers since the concept of open source is universal all over the world.  相似文献   

11.
This study characterized students' online collaborative discourse from a theory‐building perspective and examined its relation to epistemic and conceptual understanding. Fifty‐two fifth graders' Knowledge Forum discussions on electricity were analysed. Discourse moves were coded within the inquiry threads, and two key epistemic patterns were identified: problem‐centred uptake and theory‐building moves. Analysis showed that higher‐quality discourse threads included more problem‐centred uptake moves in which ideas were built more coherently on each other to address the central problem. There were also more theory‐building moves on explanation and sustain inquiry. We also examined the relationship between discourse moves and conceptual‐epistemic understanding. Regression analyses showed that problem‐centred uptake predicted epistemic cognition beyond prior epistemic cognition and that theory‐building moves on explanation predicted students' conceptual understanding beyond their prior science understanding. Implications for fostering more productive discourse and sophisticated epistemic cognitions using online discussion are discussed.  相似文献   

12.
一般说来,寻找满足一定结构性质的对象结构是困难的。概率方法提供了解决此类问题的途径:证明满足一定结构性质的对象的概率大于零。在概率方法中,局部引理是一个关键技术。本文介绍了局部引理的基本原理和使用方法,并将其应用到估计(r,s)-SAT问题中临界函数的下界。  相似文献   

13.
Social networks have intruded in human life by providing new technological innovations in a range of fields, including the education. The use of social networks in education has the potential to extend e‐learning and to introduce new forms of tutoring, communication, and collaboration between students and instructors. Thus, e‐learning is the threshold of Social Networking‐based Learning (SN‐Learning). SN‐Learning consists of a new term, introduced in this paper, and involves e‐learning systems with social networking characteristics or learning through social networking platforms. To this direction, the main objective of this paper is to present this new technological advancement emerged nowadays and to evaluate relevant applications of the last decade using our adjusted evaluation framework, EV‐SNL, in order to highlight their strengths and weaknesses regarding digital learning. The major finding is that SN‐Learning systems focus mainly on the incorporation of social features and do not provide yet personalized and adaptive tutoring. This research provides guidelines to computer science researchers on the design and implementation of SN‐Learning platforms using artificial intelligence and modelling techniques. Moreover, it can support teachers of different fields so that they can enhance their instruction with new technologies. There is scope for a lot of improvement.  相似文献   

14.
While peer‐to‐peer (P2P) financing mechanisms have recently gained significant popularity, small and medium sized enterprise (SME) entrepreneurs still harbor a considerable degree of skepticism about the role of governments in promoting alternative supply chain finance (SCF) solutions in the re‐emergence of supply chain (SC) localization. This paper studies the SC financing problem of a capital‐constrained SME entrepreneur under two alternative financing schemes provided by an online P2P lending‐investment platform, namely debt financing (DF) and equity financing (EF). Considering the competition between a local and a foreign SC in a shared market, we investigate the direct (i.e., subsidizing domestic production) and indirect (i.e., subsidizing P2P platform service fee) roles of government intervention toward SC localization. Formulating a three‐level Stackelberg game model, this paper presents a scenario‐based decision‐making framework to jointly evaluate four different SCF scenarios through the lens of local SC, P2P financing platforms, and government. The results reveal that there exist three possible regions (i.e., DF, EF, and Conflict), within which the government and the P2P financing platforms can examine the alternative SCF schemes in order to achieve a mutually agreeable agreement. Our sensitivity analysis on interest rate and exchange ratio suggests that, when financed via an online P2P lending platform (i.e., DF), the local SC always achieves a higher profit under the direct intervention policy. The indirect policy, however, is preferred only when EF is the main source of SCF and the exchange ratio is sufficiently high.  相似文献   

15.
The literature on the challenges of and potential solutions to architecting cloud‐based systems is rapidly growing but is scattered. It is important to systematically analyze and synthesize the existing research on architecting cloud‐based software systems in order to build a cohesive body of knowledge of the reported challenges and solutions. We have systematically identified and reviewed 133 papers that report architecture‐related challenges and solutions for cloud‐based software systems. This paper reports the methodological details, findings, and implications of a systematic review that has enabled us to identify 44 unique categories of challenges and associated solutions for architecting cloud‐based software systems. We assert that the identified challenges and solutions classified into the categories form a body of knowledge that can be leveraged for designing or evaluating software architectures for cloud‐based systems. Our key conclusions are that a large number of primary studies focus on middleware services aimed at achieving scalability, performance, response time, and efficient resource optimization. Architecting cloud‐based systems presents unique challenges as the systems to be designed range from pervasive embedded systems and enterprise applications to smart devices with Internet of Things. We also conclude that there is a huge potential of research on architecting cloud‐based systems in areas related to green computing, energy efficient systems, mobile cloud computing, and Internet of Things. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

16.
C. M. Huang  M. Y. Jang  Y. C. Chao 《Software》2000,30(13):1485-1507
This work presents the development of an integrated computer and telephone‐accessed WWW system (CTW) to provide a ubiquitous web access service. The CTW system serves as an intermediary between the telephone user and web sites. The CTW system retrieves and then converts the proposed Hyper Phone Markup Language (HPML) specified web pages into speech patterns. Telephone users can access information, including form‐based transaction services, on HPML‐specified web pages using a telephone set anywhere in the world by connecting to the CTW system. Another feature of CTW is that HPML‐ specified web pages stored in cyberspace can also be accessed via regular browsers, including the current Netscape Navigator and Microsoft Internet Explorer. The CTW system provides a ubiquitous web access service for users at any degree of web‐literacy by integrating well‐installed telephone networks and the Internet. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   

17.
Abstract— The design and implementation of a wavelet‐based addressing technique capable of displaying gray shades is presented. The hardware complexity of the display drivers has been reduced by adding a few analog multiplexers that are common to the drivers. The controller was implemented by using a low‐cost complex programmable logic device (CPLD) and it was demonstrated by displaying 16 gray shades in a liquid‐crystal display.  相似文献   

18.
Mobile‐based micro‐learning has gained a lot of attention lately, especially for work‐based and corporate training. It combines features of mobile learning and micro‐learning to deliver small learning units and short‐term learning activities. The current study uses the lens of the Self‐Determination Theory of motivation and proposes a series of Mobile‐Based micro‐Learning and Assessment (MBmLA) homework activities to improve high school students' motivation and learning performance in science. An experiment was conducted to evaluate the effectiveness of the proposed approach. One hundred and eight students of a senior‐level high school in Europe were randomly assigned into either a control condition (conventional paper‐based homework approach) or an experimental (MBmLA approach) condition. The study carried out for a period of 5 weeks. From the experimental results, it was found that, in comparison to the conventional paper‐based approach, the proposed MBmLA approach enhanced students' basic psychological needs of self‐perceived autonomy, competence, and relatedness and improved students' exam performance in terms of factual knowledge. Moreover, students self‐reported greater learning satisfaction with the mobile‐based microassessment and micro‐learning homework tasks. Implications on educational practices as well as future research are discussed.  相似文献   

19.
The term waveform engineering denotes all those circuit design techniques that are based on shaping the transistor voltage and current waveforms. From a general perspective, these design techniques can be grouped in two main categories according to the adopted design tool: measurement‐ and model‐based. In the last two decades, thanks to the proliferation of setups enabling calibrated waveform acquisition at microwave frequencies, waveform engineering has attracted continuously increasing interest in the microwave engineering community. In this article, a comprehensive analysis of the waveform‐engineering based design techniques is reported, paying particular attention to the advantages and drawbacks associated to each approach.  相似文献   

20.
This paper investigates geometrically (Q,S,R)‐incremental dissipativity and incremental stability for switched time‐varying nonlinear discrete‐time systems. A geometrically (Q,S,R)‐incremental dissipativity concept is proposed for switched nonlinear discrete‐time systems by using multiple storage functions and multiple incremental supply rate. Furthermore, the sufficient conditions of geometrically (Q,S,R)‐incremental dissipativity are given under the design of state‐dependent switching law. The incremental stability conditions are derived for geometrically (Q,S,R)‐incrementally dissipative switched systems. By designing of a composite state‐dependent switching law, the feedback interconnected switched systems are ensured to be geometrically (Q,S,R)‐incrementally dissipative. A numerical example is given to illustrate the validity of the proposed approach.  相似文献   

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