Searching frequent patterns in transactional databases is considered as one of the most important data mining problems and Apriori is one of the typical algorithms for this task. Developing fast and efficient algorith...
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Uniform linear array (ULA)-based TDL structure offers good performance metrics when the signal sources are located at the middle angles and it shows poor performance when the signal sources are close to the array endf...
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ISBN:
(纸本)9781467311496
Uniform linear array (ULA)-based TDL structure offers good performance metrics when the signal sources are located at the middle angles and it shows poor performance when the signal sources are close to the array endflre. In this paper, a new approach is proposed which offers higher performance and desired beamforming on TDL structure when the wideband uncorrelated radio sources are close to the array endfire. This new TDL structure is based on Shirvani-Akbari array (SAA). Numerical results of this investigation show that both ULA-based and SAA-based TDL structures offer the same performance where the signals of interest located at middle angles. But, where the signals are close to the array endfire the SAA-based TDL structure has much higher performance. The array factor (AF) in center frequency for different angles and three well-known performance metrics, normalized mean square error (NMSE), signal to interference plus noise ratio (SINK) and bit error rate (BER) are evaluated for both ULA-based and SAA-based TDL structures.
This paper presents a new fast template matching method with partial skipping using sub-template. In this method, we use sub-template to search point by point in the current searched window, and compare every SAD with...
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ISBN:
(纸本)9781467301732
This paper presents a new fast template matching method with partial skipping using sub-template. In this method, we use sub-template to search point by point in the current searched window, and compare every SAD with threshold, if some SAD exceeds the threshold, set the new threshold equal to this SAD value and this point is one potential optimization location, when all points in the current window are compared, we will get a minimum value and a optimization location, then skip the other points whose SAD is not the minimum value. In other words, the searching step is that template size subtracts the sub-template size, and we set the next threshold equal to the current optimization SAD value, we update the threshold and the optimal point until the end of the searched image like this, then will find the global minimum points and its SAD value. Experimental results show that the proposed method is near one hundred times faster than the conventional template match method.
Most existing cancelab.e biometrie frameworks are based on one-dimensional (ID) vectors rather than two-dimensional (2D) images or feature matrices. 2D cancelab.e biometrics, generated directly from images of feature ...
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Location Determination in an indoor environment is a challenge being faced by wireless industries. The concept of the indoor geolocation was established in order to provide the user's location inside buildings dur...
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Location Determination in an indoor environment is a challenge being faced by wireless industries. The concept of the indoor geolocation was established in order to provide the user's location inside buildings during an emergency where global navigation satellite system (GNSS) services are not availab.e. Keeping public safety in mind, it is important not only to estimate the position, but also to provide a high level of reliability. The paper presents practical results and issues related to the accuracy of an indoor geolocation system, which uses a wideband code division multiple access (WCDMA) signal at a 2.45 GHz carrier frequency. This experiment employs a hybrid Time Difference Of Arrival (TDOA) / Received signal Strength (RSS) algorithm and a TDOA only algorithm. Practical results indicate that the positioning performance is improved by using the hybrid TDOA/RSS algorithm as compared to the TDOA only algorithm.
In digital tomosynthesis (DTS), accurate scatter correction is often necessary for quantitative analysis. This is especially important because low energy x-ray of 10-40 keV, which is widely used for the breast imaging...
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ISBN:
(纸本)9781457718571
In digital tomosynthesis (DTS), accurate scatter correction is often necessary for quantitative analysis. This is especially important because low energy x-ray of 10-40 keV, which is widely used for the breast imaging to enhance the contrast between adipose and glandular, results in high scatter fraction. In this paper, we propose an iterative scatter correction for digital tomopsynthesis using composition ratio update and GPU based Monte Carlo simulation (MCS). One of the technical difficulty in scatter estimation using MCS for tomosynthesis is that accurate segmentation of 3D volume is very difficult due to the low resolution of the reconstruction object. Thus, an intermediate surrogate object is introduced to represent composition ratio between adipose and glandular. We show that the composition ratio can be calculated using average attenuation coefficients. Another technical challenge is extremely high computational cost of MCS. We overcome this using GPU based ultra-fast MCS. Our results demonstrate that our iterative scatter correction using composition ratio update is indeed effective in improving the quality of the reconstruction object in a reasonable time frame.
Recently, material decomposition using multi energy photon counting x-ray detector (PCXD) have been one of the very active areas of researches. Even with a few success, decomposition of three materials, including mali...
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ISBN:
(纸本)9781457718571
Recently, material decomposition using multi energy photon counting x-ray detector (PCXD) have been one of the very active areas of researches. Even with a few success, decomposition of three materials, including malignant tissue, has been still considered a difficult problem and systematic studies are still required. In this paper, we propose a statistical framework for decomposition of three material using PCXD. In particular, we derive an energy level optimization algorithm using the theory of minimum variance unbiased estimator (MVUE), and iterative update of material composition as well as system parameter estimation under a unified statistical estimation framework. Experiment results using physical breast phantom as well as real ex vivo breast data confirm that the proposed algorithm can accurately decompose three materials including malignant tissue.
Chiang's hierarchical phrase-based (HPB) translation model advances the state-of-the-art in statistical machine translation by expanding conventional phrases to hierarchical phrases - phrases that contain sub-phra...
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ISBN:
(纸本)9781622765928;1622765923
Chiang's hierarchical phrase-based (HPB) translation model advances the state-of-the-art in statistical machine translation by expanding conventional phrases to hierarchical phrases - phrases that contain sub-phrases. However, the original HPB model is prone to over-generation due to lack of linguistic knowledge: the grammar may suggest more derivations than appropriate, many of which may lead to ungrammatical translations. On the other hand, limitations of glue grammar rules in the original HPB model may actually prevent systems from considering some reasonable derivations. This paper presents a simple but effective translation model, called the Head-Driven HPB (HD-HPB) model, which incorporates head information in translation rules to better capture syntax-driven information in a derivation. In addition, unlike the original glue rules, the HD-HPB model allows improved reordering between any two neighboring non-terminals to explore a larger reordering search space. An extensive set of experiments on Chinese-English translation on four NIST MT test sets, using both a small and a large training set, show that our HD-HPB model consistently and statistically significantly outperforms Chiang's model as well as a source side SAMT-style model.
This paper presents an extension of Chiang's hierarchical phrase-based (HPB) model, called Head-Driven HPB (HD-HPB), which incorporates head information in translation rules to better capture syntax-driven informa...
ISBN:
(纸本)9781622761715
This paper presents an extension of Chiang's hierarchical phrase-based (HPB) model, called Head-Driven HPB (HD-HPB), which incorporates head information in translation rules to better capture syntax-driven information, as well as improved reordering between any two neighboring non-terminals at any stage of a derivation to explore a larger reordering search space. Experiments on Chinese-English translation on four NIST MT test sets show that the HD-HPB model significantly outperforms Chiang's model with average gains of 1.91 points absolute in BLEU.
Keyword spotting refers to detection of all occurrences of any given word in a speech utterance. In this paper, we define the keyword spotting problem as a binary classification problem and propose a discriminative ap...
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