918 resultados para Strongly Semantic Information
Resumo:
Internet chatrooms are common means of interaction and communications, and they carry valuable information about formal or ad-hoc formation of groups with diverse objectives. This work presents a fully automated surveillance system for data collection and analysis in Internet chatrooms. The system has two components: First, it has an eavesdropping tool which collects statistics on individual (chatter) and chatroom behavior. This data can be used to profile a chatroom and its chatters. Second, it has a computational discovery algorithm based on Singular Value Decomposition (SVD) to locate hidden communities and communication patterns within a chatroom. The eavesdropping tool is used for fine tuning the SVD-based discovery algorithm which can be deployed in real-time and requires no semantic information processing. The evaluation of the system on real data shows that (i) statistical properties of different chatrooms vary significantly, thus profiling is possible, (ii) SVD-based algorithm has up to 70-80% accuracy to discover groups of chatters.
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Affect is an important feature of multimedia content and conveys valuable information for multimedia indexing and retrieval. Most existing studies for affective content analysis are limited to low-level features or mid-level representations, and are generally criticized for their incapacity to address the gap between low-level features and high-level human affective perception. The facial expressions of subjects in images carry important semantic information that can substantially influence human affective perception, but have been seldom investigated for affective classification of facial images towards practical applications. This paper presents an automatic image emotion detector (IED) for affective classification of practical (or non-laboratory) data using facial expressions, where a lot of “real-world” challenges are present, including pose, illumination, and size variations etc. The proposed method is novel, with its framework designed specifically to overcome these challenges using multi-view versions of face and fiducial point detectors, and a combination of point-based texture and geometry. Performance comparisons of several key parameters of relevant algorithms are conducted to explore the optimum parameters for high accuracy and fast computation speed. A comprehensive set of experiments with existing and new datasets, shows that the method is effective despite pose variations, fast, and appropriate for large-scale data, and as accurate as the method with state-of-the-art performance on laboratory-based data. The proposed method was also applied to affective classification of images from the British Broadcast Corporation (BBC) in a task typical for a practical application providing some valuable insights.
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Effective leaders are believed to inspire followers by providing inclusive visions of the future that followers can identify with. In the present study, we examined the neural mechanisms underlying this process, testing key hypotheses derived from transformational and social identity approaches to leadership. While undergoing functional MRI, supporters from the two major Australian political parties (Liberal vs. Labor) were presented with inspirational collective-oriented and noninspirational personal-oriented statements made by in-group and out-group leaders. Imaging data revealed that inspirational (rather than noninspirational) statements from in-group leaders were associated with increased activation in the bilateral rostral inferior parietal lobule, pars opercularis, and posterior midcingulate cortex: brain areas that are typically implicated in controlling semantic information processing. In contrast, for out-group leaders, greater activation in these areas was associated with noninspirational statements. In addition, noninspirational statements by in-group (but not out-group) leaders resulted in increased activation in the medial prefrontal cortex, an area typically associated with reasoning about a person’s mental state. These results show that followers processed identical statements qualitatively differently as a function of leaders’ group membership, thus demonstrating that shared identity acts as an amplifier for inspirational leadership communication.
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PROFESSION, PERSON AND WORLDVIEW AT A TURNING POINT A Study of University Libraries and Library Staff in the Information Age 1970 - 2005 The incongruity between commonly held ideas of libraries and librarians and the changes that have occurred in libraries since 2000 provided the impulse for this work. The object is to find out if the changes of the last few decades have penetrated to a deeper level, that is, if they have caused changes in the values and world views of library staff and management. The study focuses on Finnish university libraries and the people who work in them. The theoretical framework is provided by the concepts of world view (values, the concept of time, man and self, the experience of the supernatural and the holy, community and leadership). The viewpoint, framework and methods of the study place it in the area of Comparative Religion by applying the world view framework. The time frame is the information age, which has deeply affected Finnish society and scholarly communication from 1970 to 2005. The source material of the study comprises 30 life stories; somewhat more than half of the stories come from the University of Helsinki, and the rest from the other eight universities. Written sources include library journals, planning documents and historical accounts of libraries. The experiences and research diaries of the research worker are also used as source material. The world view questions are discussed on different levels: 1) recognition of the differences and similarities in the values of the library sphere and the university sphere, 2) examination of the world view elements, community and leadership based on the life stories, and 3) the three phases of the effects of information technology on the university libraries and those who work in them. In comparing the values of the library sphere and the university sphere, the appreciation of creative work and culture as well as the founding principles of science and research are jointly held values. The main difference between the values in the university and library spheres concerns competition and service. Competition is part of the university as an institution of research work. The core value of the library sphere is service, which creates the essential ethos of library work. The ethical principles of the library sphere also include the values of democracy and equality as well as the value of intellectual freedom. There is also a difference between an essential value in the university sphere, the value of autonomy and academic freedom on the one hand, and the global value of the library sphere - organizing operations in a practical and efficient way on the other hand. Implementing this value can also create tension between the research community and the library. Based on the life stories, similarities can be found in the values of the library staff members. The value of service seems to be of primary importance for all who are committed to library work and who find it interesting and rewarding. The service role of the library staff can be extended from information services provider to include the roles of teacher, listener and even therapist, all needed in a competitive research community. The values of democracy and equality also emerge fairly strongly. The information age development has progressed in three phases in the libraries from the 1960s onward. In the third phase beginning in the mid 1990s, the increased usage of electronic resources has set fundamental changes in motion. The changes have affected basic values and the concept of time as well as the hierarchies and valuations within the library community. In addition to and as a replacement for the library possessing a local identity and operational model, a networked, global library is emerging. The changes have brought tension both to the library communities and to the relationship between the university community and the library. Future orientation can be said to be the key concept for change; it affects where the ideals and models for operations are taken from. Future orientation manifests itself as changes in metaphors, changes in the model of a good librarian and as communal valuations. Tension between the libraries and research communities can arise if the research community pictures the library primarily as a traditional library building with a local identity, whereas the 21st century library staff and directors are affected by future orientation and membership in a networked library sphere, working proactively to develop their libraries.
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Practical usage of machine learning is gaining strategic importance in enterprises looking for business intelligence. However, most enterprise data is distributed in multiple relational databases with expert-designed schema. Using traditional single-table machine learning techniques over such data not only incur a computational penalty for converting to a flat form (mega-join), even the human-specified semantic information present in the relations is lost. In this paper, we present a practical, two-phase hierarchical meta-classification algorithm for relational databases with a semantic divide and conquer approach. We propose a recursive, prediction aggregation technique over heterogeneous classifiers applied on individual database tables. The proposed algorithm was evaluated on three diverse datasets. namely TPCH, PKDD and UCI benchmarks and showed considerable reduction in classification time without any loss of prediction accuracy. (C) 2012 Elsevier Ltd. All rights reserved.
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Resumen: La memoria semántica permite almacenar información acerca del significado de los objetos, las palabras y del mundo en general. Este conocimiento se altera en pacientes con Demencia Semántica, Enfermedad de Alzheimer y encefalitis por virus herpes, entre otros. El compromiso de la información semántica debe ser evaluado con herramientas que contemplen los diferentes aspectos que sustentan su organización. El objetivo del presente trabajo es hacer una revisión exhaustiva de las diferentes tareas que permiten indagar el procesamiento semántico e indicar aquellas que han sido diseñadas o adaptadas para ser usadas en la población rioplatense.
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The brain extracts useful features from a maelstrom of sensory information, and a fundamental goal of theoretical neuroscience is to work out how it does so. One proposed feature extraction strategy is motivated by the observation that the meaning of sensory data, such as the identity of a moving visual object, is often more persistent than the activation of any single sensory receptor. This notion is embodied in the slow feature analysis (SFA) algorithm, which uses “slowness” as an heuristic by which to extract semantic information from multi-dimensional time-series. Here, we develop a probabilistic interpretation of this algorithm showing that inference and learning in the limiting case of a suitable probabilistic model yield exactly the results of SFA. Similar equivalences have proved useful in interpreting and extending comparable algorithms such as independent component analysis. For SFA, we use the equivalent probabilistic model as a conceptual spring-board, with which to motivate several novel extensions to the algorithm.
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The broadcast soccer video is usually recorded by one main camera, which is constantly gazing somewhere of playfield where a highlight event is happening. So the camera parameters and their variety have close relationship with semantic information of soccer video, and much interest has been caught in camera calibration for soccer video. The previous calibration methods either deal with goal scene, or have strict calibration conditions and high complexity. So, it does not properly handle the non-goal scene such as midfield or center-forward scene. In this paper, based on a new soccer field model, a field symbol extraction algorithm is proposed to extract the calibration information. Then a two-stage calibration approach is developed which can calibrate camera not only for goal scene but also for non-goal scene. The preliminary experimental results demonstrate its robustness and accuracy. (c) 2010 Elsevier B.V. All rights reserved.
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在低挡微机中速度较慢的串行处理硬设备条件下,利用本文提出的启发式概念,分层搜索和匹配策略以及设置最大搜索长度等方法,可使推理速度提高一个数量级以上.此外,通过引入语义信息,分阶段消除歧义,自顶向下与自底向上相结合,以及把一般疑问句一律变成相应陈述句的方法,解决了自动英语句法分析中的一系列难题,缩小了知识库的规模。
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This study was aimed at examining the effects of contexts on pronouns comprehension in discourse comprehension. When a pronoun appears in a discourse in which there are not less than two antecedents, its comprehension may be influenced by the local and global contexts. This study explored the effects of global and local contexts on pronouns comprehension, the comprehension process of implicature in pronouns comprehension, the relationship between the effects of local and global contexts on pronouns comprehension . The main conclusions of the present study were: 1 The global contexts and the local contexts prior to the pronoun both influenced the pronouns comprehension, and the effects of the two contexts were additive. When the global contexts were inconsistent with the local context, the comprehender understood the pronouns based on the local context. 2 When a pronoun appears in a discourse, the comprehender understand the pronouns based on the global context immediately. After the local context appears in succession, the comprehender understand the pronouns based on the local context. 3 If the semantic information posterior to the pronouns are needed to decide the antecedent of the pronouns, the semantic information would be influenced by the global contexts prior to pronouns. 4 When a pronoun appears in global contexts and local contexts prior to the pronouns, the pronouns comprehension were influenced by the two contexts. The global contexts played role in the initial stage of pronouns comprehension, and the local contexts, in despite of being prior to the pronouns, played role in the later stage of pronouns comprehension. 5 Language was not an absolute incremental semantic interpretation process. Some information prior the target words didn’t influence the processing of target words immediately, but played role in later stage.
Resumo:
As Levelt and Meyer (2000) noted, because studies of lexical access during multiword utterances production such as phrases and sentences, they raise two novel questions which studies of single word production do not. Firstly, does the access of different words in a sentence occur in a parallel or a serial fashion? Secondly, does the access of the different words in a sentence occur in an interactive or a discrete fashion? The latter question concerns the horizontal information flow (Smith & Wheeldon, 2004), which is a very important aspect of continuous speech production. A variant of the picture–word interference paradigm combining with eye-tracking technique and a dual task paradigm was used in 7 experiments to investigate the horizontal information flow of semantic and phonological information between nouns in spoken Mandarin Chinese sentences. The results suggested that: 1. Before speech onset, semantic information of different words accross the whole sentence has been activated, while phonological activation has been limited within the first phrase of the sentence. 2. Before speech onset, speaker will look ahead and check the semantic information of latter words as the first noun is beening processed, such looking ahead for phonological information can just occur within the first phrase of the sentence. 3. After speech onset, speaker will concentrate on the content words beyond the first one and will check the semantic information of other words with the same sentence. 4. The result suggested that the lexical accesses of multiple words during spoken sentence production are processed in a partly serial and partly parallel manner and stands for the Unit-by-Unit and Incremental view proposed by Levelt (2000). 5. The horizontal information flow during spoken sentence production is not an automatic process and is constrained by cognitive resource.
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A number of functional neuroimaging studies with skilled readers consistently showed activation to visual words in the left mid-fusiform cortex in occipitotemporal sulcus (LMFC-OTS). Neuropsychological studies also showed that lesions at left ventral occipitotemporal areas result in impairment in visual word processing. Based on these empirical observations and some theoretical speculations, a few researchers postulated that the LMFC-OTS is responsible for instant parallel and holistic extraction of the abstract representation of letter strings, and labeled this piece of cortex as “visual word form area” (VWFA). Nonetheless, functional neuroimaging studies alone is basically a correlative rather than causal approach, and lesions in the previous studies were typically not constrained within LMFC-OTS but also involving other brain regions beyond this area. Given these limitations, it remains unanswered for three fundamental questions: is LMFC-OTS necessary for visual word processing? is this functionally selective for visual word processing while unnecessary for processing of non-visual word stimuli? what are its function properties in visual word processing? This thesis aimed to address these questions through a series of neuropsychological, anatomical and functional MRI experiments in four patients with different degrees of impairments in the left fusiform gyrus. Necessity: Detailed analysis of anatomical brain images revealed that the four patients had differential foci of brain infarction. Specifically, the LMFC-OTS was damaged in one patient, while it remained intact in the other three. Neuropsychological experiments showed that the patient with lesions in the LMFC-OTS had severe impairments in reading aloud and recognizing Chinese characters, i.e., pure alexia. The patient with intact LMFC-OTS but information from the left visual field (LVF) was blocked due to lesions in the splenium of corpus callosum, showed impairment in Chinese characters recognition when the stimuli were presented in the LVF but not in the RVF, i.e. left hemialexia. In contrast, the other two patients with intact LMFC-OTS had normal function in processing Chinese characters. The fMRI experiments demonstrated that there was no significant activation to Chinese characters in the LMFC-OTS of the pure alexic patient and of the patient with left hemialexia when the stimuli were presented in the LVF. On the other hand, this patient, when Chinese characters were presented in right visual field, and the other two with intact LMFC-OTS had activation in the LMFC-OTS. These results together point to the necessity of the LMFC-OTS for Chinese character processing. Selectivity: We tested selectivity of the LMFC-OTS for visual word processing through systematically examining the patients’ ability for processing visual vs. auditory words, and word vs. non-word visual stimuli, such as faces, objects and colors. Results showed that the pure alexic patients could normally process auditory words (expression, understanding and repetition of orally presented words) and non-word visual stimuli (faces, objects, colors and numbers). Although the patient showed some impairments in naming faces, objects and colors, his performance scores were only slightly lower or not significantly different relative to those of the patients with intact LMFC-OTS. These data provide compelling evidence that the LMFC-OTS is not requisite for processing non-visual word stimuli, thus has selectivity for visual word processing. Functional properties: With tasks involving multiple levels and aspects of word processing, including Chinese character reading, phonological judgment, semantic judgment, identity judgment of abstract visual word representation, lexical decision, perceptual judgment of visual word appearance, and dictation, copying, voluntary writing, etc., we attempted to reveal the most critical dysfunction caused by damage in the LMFC-OTS, thus to clarify the most essential function of this region. Results showed that in addition to dysfunctions in Chinese character reading, phonological and semantic judgment, the patient with lesions at LMFC-OTS failed to judge correctly whether two characters (including compound and simple characters) with different surface features (e.g., different fonts, printed vs. handwritten vs. calligraphy styles, simplified characters vs. traditional characters, different orientations of strokes or whole characters) had the same abstract representation. The patient initially showed severe impairments in processing both simple characters and compound characters. He could only copy a compound character in a stroke-by-stroke manner, but not by character-by-character or even by radical-by-radical manners. During the recovery process, namely five months later, the patient could complete the abstract representation tasks of simple characters, but showed no improvement for compound characters. However, he then could copy compound characters in a radical-by-radical manner. Furthermore, it seems that the recovery of copying paralleled to that of judgment of abstract representation. These observations indicate that lesions of the LMFC-OTS in the pure alexic patients caused several damage in the ability of extracting the abstract representation from lower level units to higher level units, and the patient had especial difficulty to extract the abstract representation of whole character from its secondary units (e.g., radicals or single characters) and this ability was resistant to recover from impairment. Therefore, the LMFC-OTS appears to be responsible for the multilevel (particularly higher levels) abstract representations of visual word form. Successful extraction seems independent on access to phonological and semantic information, given the alexic patient showed severe impairments in reading aloud and semantic processing on simple characters while maintenance of intact judgment on their abstract representation. However, it is also possible that the interaction between the abstract representation and its related information e.g. phonological and semantic information was damaged as well in this patient. Taken together, we conclude that: 1) the LMFC-OTS is necessary for Chinese character processing, 2) it is selective for Chinese character processing, and 3) its critical function is to extract multiple levels of abstract representation of visual word and possibly to transmit it to phonological and semantic systems.
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Unlike alphabetic languages, Chinese language is ideographical writing system. Each Chinese character is single-syllable and usually has a direct meaning. So Chinese characters are a kind of valuable experimental material used for research on reading and comparisons of the reading mechanism of different language. In this paper, the normal persons and the patients with semantic dementia were respectively scheduled for two parts of experimental studies on the orthographic, phonologic, semantic and frequency effects of reading of Chinese characters. The Stroop-like character-picture interference experimental paradigm was used to investigate the orthographic, phonologic, semantic and frequency effects of Chinese characters on picture naming when they were presented with pictures to normal persons. The results indicated that the orthographic facilitation effect, phonologic facilitation effect, and semantic interference effect occurred at different SOA values. The orthographic and phonologic facilitation effects were independent. It was for the first time shown that the interaction between orthographic variable and semantic variable occurred when the high-frequency Chinese characters were read. Phonologic representation was activated quicker than semantic representation, by comparison of their SOA. Generally, it means that there is reading without meaning in Chinese character among the normal persons. The orthographic, phonologic, semantic, frequency and concrete effects of Chinese characters were further investigated among the dementia patients with DAT(dementia of Alzheimer's type disease) or CVA or both. They all have an impaired semantic memory. The results showed that patients with dementia could read the names of the pictures aloud while they could not name them or match them with a right character correctly. This is reading impairment without meaning in Chinese among the dementia patients. Meanwhile, they had a selective reading impairment and more LARC(a legitimate alternative reading of components) mistakes especially when reading low-frequency irregular, low-frequency inconsistent and abstract Chinese characters. With the patients' semantic impairment developed, their ability to read the pictures names would remain whereas their ability to read low-frequency irregular and low-frequency inconsistency Chinese characters was reduced. These results indicated that low-frequency irregular Chinese characters can be read correctly only when it is supported by their semantic information. Based on the above results of reading without meaning and of reading of low-frequency irregular Chinese characters supported by their semantic information, it is reasonable to suggest that at least two routes are involved in the process of reading Chinese characters. They are direct phonologic route and indirect semantic route; moreover, the two routes are independent.
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The research has studied, how Selectivity of attention develops from children (grade 2) to young adults (undergraduates) by the means of incidental learning tasks, in which two variates were used. One was the Semantic relation between target and context, the other was methods of processing (identifying) target. The results were: (1) Selectivity of attention develops with increasing of age. (2) Selectivity of attention is more greatly affected by the semantic relation between target and context with increasing of age. The phenomeon may be caused by that the adults are more proficient in processing semantic information than the children. (3) The older the individual is, the less Selectivity of attention is affected by the processing methods. It perhaps proves that the adults process semantic information more automaticly.
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According to PDP theory, the author tries to use ANN method in sentence understanding. In input layer, distributed knowledge representation and integrate syntactic, semantic information (of the word in Chinese sentence) and context information are used to complete the case role assignment of six types of Chinese sentence by parallel processing. The model is a four-layer forward network, consisting of input layer, two hidden layers, and output layer(case role layer). In addition, the neural network method and the traditional symbol processing method used in natural language understanding is compared and analyzed, and a conclusion could be made: the neural network should be used as a powerful tool in this area.