The Delta parallel robot establishes itself as one of the most successful parallel robot designs thanks to its intrinsic properties. Generally, based on the type of actuator, the 3-DOF Delta robot falls into two group...
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ISBN:
(纸本)9781538657041
The Delta parallel robot establishes itself as one of the most successful parallel robot designs thanks to its intrinsic properties. Generally, based on the type of actuator, the 3-DOF Delta robot falls into two groups, namely, revolute-input and prismatic-input. The main aim of this paper consists in evaluating and comparing the kinematic performance of the two foregoing types of Delta robots. So far, different kinematic sensitivity indices have been proposed. In this paper, by employing different kinematic sensitivity indices such as manipulability, dimensionally kinematic sensitivity and weighted kinematic sensitivity indices. the kinetostatic performance of the aforementioned robots are compared over a certain workspace. The obtained results showed that the sensitivity of prismatic Delta robot is high in the center of the workspace and the sensitivity increases when the end-effector moves to edges from the center. However sensitivity of the revolute Delta robot is totally different. It is high on the edges and it decreases by moving to center. weighted kinematic sensitivity results show that geometrical features of the robots are very important and it changes the sensitivity values and trend greatly. Moreover, in order to enhance the kinematic performance of the robots, the configuration of the robots are redesigned using optimization of the kinematic sensitivity indices. The results of this paper revealed that kinematic sensitivity indices can be employed in the design step of the robot to reach an optimal kinematic sensitivity in the workspace.
Speech enhancement is an essential technique to process degraded audio in various applications. Beamforming to eliminate interferences based on sensor arrays is the most well-known method for this issue. However, trad...
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Speech enhancement is an essential technique to process degraded audio in various applications. Beamforming to eliminate interferences based on sensor arrays is the most well-known method for this issue. However, trad...
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Speech enhancement is an essential technique to process degraded audio in various applications. Beamforming to eliminate interferences based on sensor arrays is the most well-known method for this issue. However, traditional beamformers often face magnitude incoherence towards received signals due to directional weighting. Therefore, a novel dual-channel beamformer based on time-delay compensation (TDC) and shifted principal components analysis (PCA) is presented in this work. Firstly, our enhancement algorithm utilizes TDC estimator to preserve binaural cues, including interaural time-delay and intensity difference. Then the estimated cues are comprised to improve the shifted PCA, which can reduce noise by extracting primary components. Finally, the aforehand processed audio are input to a beamformer with post-filter to obtain enhanced speech. Experiments have demonstrated that the proposed algorithm could achieve some superiorities in speech intelligibility compared with the state-of-the-arts against real scenarios.
Understanding Indirect Speech Acts (ISAs) is an integral function of human understanding of natural language. Recent attempts at understanding ISAs have used rule-based approaches to map utterances to deep semantics. ...
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This paper presents the results of a comprehensive study on the efficiency of planar parallel mechanisms, considering their kinetostatic performance and also, their workspace. This aim is approached upon proceeding si...
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With the enormous growth of online reviews in Internet, sentiment analysis has received more and more attention in information retrieval and natural language processing community. Up to now there are very few research...
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With the enormous growth of online reviews in Internet, sentiment analysis has received more and more attention in information retrieval and natural language processing community. Up to now there are very few researches conducted on sentiment analysis for Persian documents. This paper considers the problem of sentiment classification for online customer reviews in Persian language. One of the challenges of Persian language is using of a wide variety of declensional suffixes. Another common problem of Persian text is word spacing. In Persian in addition to white space as interwords space, an intra-word space called pseudo-space separates word's part. One more noticeable challenge in customer reviews in Persian language is that of utilizing many informal or colloquial words in text. In this paper we study these challenges by proposing a model for sentiment classification of Persian review documents. The proposed model is based on a lemmatization approach for Persian language and is employed Naive Bayes learning algorithm for classification. Additionally we present a new feature selection method based on the mutual information method to extract the best feature collection from the initial extracted features. Finally we evaluate the performance of the model on a manually gathered collection of cellphone reviews, where the results show the effectiveness of the proposed model.
In this paper, a valid frequency range of throat signal analyses is presented. Compare to speech signals, the throat signals have many differences in the amount of information. In this context, targeting on throat sig...
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ISBN:
(纸本)9781424492220
In this paper, a valid frequency range of throat signal analyses is presented. Compare to speech signals, the throat signals have many differences in the amount of information. In this context, targeting on throat signals to find valid frequency range is one of the most important analyses for the development of new breed of feature extraction algorithm. In this respect, using analysis similarity of throat signals feature distribution and correlation analysis of throat signals in the frequency domain, the frequency range can be found with effective and quick response time to be applied to a voice command recognition system using neck-microphone. As a result, the proposed frequency range is from 200Hz (center frequency) to 2001Hz (center frequency). For the neck-microphone voice command system using the proposed frequency range, a significant reduction in time complexity of 25% can be achieved without any loss in recognition rate.
The elderly represent a valid group of users who can potentially benefit greatly from engaging with technology, such as healthcare systems or playing digital games. Yet, less attention has been given to the significan...
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This paper presents an emotional exchange framework for a socially interactive robot. The purpose of emotional exchange in social interaction between a robot and people is to make people feel that the robot is a belie...
This paper presents an emotional exchange framework for a socially interactive robot. The purpose of emotional exchange in social interaction between a robot and people is to make people feel that the robot is a believable living assistant, not a mere machine for information translation. Our emotional exchange framework is composed of the emotion recognition, generation, and expression systems. A user's emotion is recognized by multi-modality such as voice, dialogue, and touch. The robot's emotion is generated according to a psychological theory about cognitive emotions caused by the social interaction within people. Furthermore, the emotion intensity is regulated by the loyalty level of a robot to various users. The generated emotion is dynamically expressed by facial expression, gesture, and the musical sound of the robot. The proposed system, which is composed of all the three components that are necessary for a full emotional interaction cycle, is implemented in the real robot system and tested. The proposed framework can be a cornerstone for the design of emotion interaction and generation systems for robots.
This paper introduces an emotion interaction system for a service robot. The purpose of emotion interaction systems in service robots is to make people feel that the robot is not a mere machine, but reliable living as...
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