A VQ based efficient speech recognition method is introduced, and the key parameters of this method are comparatively studied. This method is especially designed for mandarin speaker dependent small size word set r...A VQ based efficient speech recognition method is introduced, and the key parameters of this method are comparatively studied. This method is especially designed for mandarin speaker dependent small size word set recognition. It has less complexity, less resource consumption but higher ARR (accurate recognition rate) compared with traditional HMM or NN approach. A large scale test on the task of 11 mandarin digits recognition shows that the WER(word error rate) can reach 3 86%. This method is suitable for being embedded in PDA (personal digital assistant), mobile phone and so on to perform voice controlling like digits dialing, name dialing, calculating, voice commanding, etc.展开更多
The design of an FPGA( field programmable gate array) based programmable SONET (synchronous optical network) OC-192 10 Gbit/s PRBS (pseudo-random binary sequence) generator and a bit interleaved polarity 8 (BI...The design of an FPGA( field programmable gate array) based programmable SONET (synchronous optical network) OC-192 10 Gbit/s PRBS (pseudo-random binary sequence) generator and a bit interleaved polarity 8 (BIP-8) error detector is presented. Implemented in a parallel feedback configuration, this tester features PRBS generation of sequences with bit lengths of 2^7 - 1,2^10- 1,2^15 - 1,2^23 - land 2^31 - 1 for up to 10 Gbit/s applications with a 10 Gbit/s optical transceiver, via the SFI-4 (OC-192 serdes-framer interface). In the OC-192 frame alignment circuit, a dichotomy search algorithm logic which performs the functions of word alignment and STM-64/OC192 de-frame speeds up the frame sync logic and reduces circuit complexity greatly. The system can be used as a low cost tester to evaluate the performance of OC-192 devices and components, taking the replacement of precious commercial PRBS testers.展开更多
In this paper, a novel approach is proposed for denoising of Chinese calligraphy tablet documents. The method includes two phases: First, a partial differential equations (PDE) based the total variation model and Otsu...In this paper, a novel approach is proposed for denoising of Chinese calligraphy tablet documents. The method includes two phases: First, a partial differential equations (PDE) based the total variation model and Otsu thresholding method are used to preprocess the calligraphy document image. Second, a new method based on run-length statistics and structure charac- teristics of Chinese characters is proposed to remove some random and ant-like noises. This includes the optimal threshold se- lection from histogram of run-length probability density, and improved Hough transform algorithm for line shape noise detection and removal. Examples are given in the paper to demonstrate the proposed method.展开更多
This paper proposes a learning-based method for text detection and text segmentation in natural scene images. First, the input image is decomposed into multiple connected-components (CCs) by Niblack clustering algorit...This paper proposes a learning-based method for text detection and text segmentation in natural scene images. First, the input image is decomposed into multiple connected-components (CCs) by Niblack clustering algorithm. Then all the CCs including text CCs and non-text CCs are verified on their text features by a 2-stage classification module, where most non-text CCs are discarded by an attentional cascade classifier and remaining CCs are further verified by an SVM. All the accepted CCs are output to result in text only binary image. Experiments with many images in different scenes showed satisfactory performance of our proposed method.展开更多
Some important tidal features of 8 major tidal constituents ( M 2, S 2, K 1, O 1, P 1, Sa, N 2 and K 2 ) in the China Seas and their adjacent sea areas were obtained using six years’ TOPEX/POSEIDON altimeter data. Th...Some important tidal features of 8 major tidal constituents ( M 2, S 2, K 1, O 1, P 1, Sa, N 2 and K 2 ) in the China Seas and their adjacent sea areas were obtained using six years’ TOPEX/POSEIDON altimeter data. The results showed that the obtained co tidal and co range charts for these major tidal constituents agreed well with those of previous researches using observational data from coastal tidal gauge stations and numerical models.展开更多
To accurately describe damage within coal, digital image processing technology was used to determine texture parameters and obtain quantitative information related to coal meso-cracks. The relationship between damage ...To accurately describe damage within coal, digital image processing technology was used to determine texture parameters and obtain quantitative information related to coal meso-cracks. The relationship between damage and mesoscopic information for coal under compression was then analysed. The shape and distribution of damage were comprehensively considered in a defined damage variable, which was based on the texture characteristic. An elastic-brittle damage model based on the mesostructure information of coal was established. As a result, the damage model can appropriately and reliably replicate the processes of initiation, expansion, cut-through and eventual destruction of microscopic damage to coal under compression. After comparison, it was proved that the predicted overall stress-strain response of the model was comparable to the experimental result.展开更多
In order to improve the detection accuracy of small objects,a neighborhood fusion-based hierarchical parallel feature pyramid network(NFPN)is proposed.Unlike the layer-by-layer structure adopted in the feature pyramid...In order to improve the detection accuracy of small objects,a neighborhood fusion-based hierarchical parallel feature pyramid network(NFPN)is proposed.Unlike the layer-by-layer structure adopted in the feature pyramid network(FPN)and deconvolutional single shot detector(DSSD),where the bottom layer of the feature pyramid network relies on the top layer,NFPN builds the feature pyramid network with no connections between the upper and lower layers.That is,it only fuses shallow features on similar scales.NFPN is highly portable and can be embedded in many models to further boost performance.Extensive experiments on PASCAL VOC 2007,2012,and COCO datasets demonstrate that the NFPN-based SSD without intricate tricks can exceed the DSSD model in terms of detection accuracy and inference speed,especially for small objects,e.g.,4%to 5%higher mAP(mean average precision)than SSD,and 2%to 3%higher mAP than DSSD.On VOC 2007 test set,the NFPN-based SSD with 300×300 input reaches 79.4%mAP at 34.6 frame/s,and the mAP can raise to 82.9%after using the multi-scale testing strategy.展开更多
With PSU/NCAR nonhydrostatic mesoscale model MM5, the rainfall process of tropical storm Fitow(0114) is simulated for 00:00 UTC 31 Aug. – 00:00 UTC 2 Sept. 2001. Mesoscale separation is performed on the results with ...With PSU/NCAR nonhydrostatic mesoscale model MM5, the rainfall process of tropical storm Fitow(0114) is simulated for 00:00 UTC 31 Aug. – 00:00 UTC 2 Sept. 2001. Mesoscale separation is performed on the results with the filtering scheme. Analyses show that the MM5 model well reproduced the position and intensity of heavy rain. Mesoscale characteristics of heavy rain were well represented in rainfall time scale, rainfall area, stream field and divergence at lower and upper levels. The interaction between inverted typhoon troughs and the mesoscale systems lead to heavy rain occurrence. The distribution of divergence fields at lower and upper levels can have a kind of indication for the rainfall. Heavy rains are closely associated with topography and land-sea distribution in South China. Weak instability is favorable to the generation of heavy rain.展开更多
As a component of streamflow, baseflow is critical for regulating seasonal distribution of river fows and stabilizing water supplies. Water resources in the arid area of Northwest China are mainly from multiple catchm...As a component of streamflow, baseflow is critical for regulating seasonal distribution of river fows and stabilizing water supplies. Water resources in the arid area of Northwest China are mainly from multiple catchments in the alpine that could be influenced by varieties of climatic, land cover, soil and geological factors. While numerous studies have been done on streamflow, systematic analysis of baseflow in the alpine river systems is scare. Based on historical daily streamflow data and the automated digital filter method of baseflow separation, this study investigated characteristics of hydrographs of overland flow, streamflow and baseflowof river systems fed by rainfall, snowmelt, glacier melt or mixtures of these. This study also calculated the recession constants and baseflow indices of 65 river systems. While the recession constant was o.oo34- o.o728 with a mean of o.o18, the baseflow index was 0.27-0.79 with a mean of 0.57. Further, Spearman's correlation analysis showed that the baseflow index was significantly correlated with catchment climatic factors (e.g., precipitation and temperature), topographic factors (e.g., elevation and slope) and aquifer properties represented by the recession constant. Multiple regression analysis indicated that the factors explained 65% of the variability of baseflow index in the studv area.展开更多
This paper discusses a neglected theme in Wittgenstein's writings on meaning and psychology from the early 1930s until 1949. Throughout this period Wittgenstein deals with aspects of meaning of words and pictures tha...This paper discusses a neglected theme in Wittgenstein's writings on meaning and psychology from the early 1930s until 1949. Throughout this period Wittgenstein deals with aspects of meaning of words and pictures that cannot be accounted for in dispositional terms but have to be related to experience and perception. Wittgenstein's reading of William James, I argue, has sharpened his eye for the many pitfalls in coming to terms with this experiential notion of meaning. James's treatment of experiences of meaning succumbs to the temptation to postulate ~~meaning-bodies," bearers of meaning apart from the way and context in which we use the particular words. I argue that the conflation of what Wittgenstein calls the transitive and intransitive use of words is at the root of postulating meaning-bodies. I also argue that contemporary treatments of experiences of meaning are similarly vulnerable to James's confusion.展开更多
In photogrammetry and remote sensing, image matching is a basic and crucial process for automatic DEM generation. In this paper we presented a image relaxation matching method based on feature points. This method can ...In photogrammetry and remote sensing, image matching is a basic and crucial process for automatic DEM generation. In this paper we presented a image relaxation matching method based on feature points. This method can be considered as an extention of regular grid point based matching. It avoids the shortcome of grid point based matching. For example, with this method, we can avoid low or even no texture area where errors frequently appear in cross correlaton matching. In the mean while, it makes full use of some mature techniques such as probability relaxation, image pyramid and the like which have already been successfully used in grid point matching process. Application of the technique to DEM generaton in different regions proved that it is more reasonable and reliable.展开更多
Character derivation means that if a graph represents several meanings, a new graph based on the original one will be created to bear one or two of the meanings, which is a natural law in Chinese writing system. The o...Character derivation means that if a graph represents several meanings, a new graph based on the original one will be created to bear one or two of the meanings, which is a natural law in Chinese writing system. The old graph is called original character, and the new generated one is called derived character. Two kinds of phenomena-derivation of cognate words (同詞孳乳) and differentiation of unidentical words (異詞別異)-promote the derivation of Chinese characters. In return, derived characters not only bear meaning of the original one, but also serve as a symbol of an independent word and consolidate the graph-meaning relationship. It deserves much attention to the law of the process of character derivation.展开更多
By the use of cross-correlation measures, the response of a symmetric Schmitt trigger (ST) driven by a random binary signal and white Gaussian noise is investigated. The results show that the information transmission...By the use of cross-correlation measures, the response of a symmetric Schmitt trigger (ST) driven by a random binary signal and white Gaussian noise is investigated. The results show that the information transmission can be enhanced when a certain amount of noise is presented, i.e., aperiodic stochastic resonance (ASR). Then, the influence of signal amplitude and the ST threshold on ASR is examined, the applicability of the ST in reducing the noise level of random signal transmission and improving the quality of output signal via ASR effect is illustrated. This research is of great interest in the field of digital communications.展开更多
Aiming to investigate the fatigue damage mechanism and bearing characteristics of multi-pillar system under cyclic loading,a series of axial cyclic loading tests with different cyclic amplitudes were carried out on tr...Aiming to investigate the fatigue damage mechanism and bearing characteristics of multi-pillar system under cyclic loading,a series of axial cyclic loading tests with different cyclic amplitudes were carried out on triple-pillar marble specimens.The acoustic emission(AE)and digital image correlation(DIC)were jointly applied to monitoring and recording damage evolution and failure behavior of each pillar,which reproduced the cataclysmic instability process of underground pillar groups.Experimental results indicated that the cyclic amplitude exceeding the threshold of damage initiation weakened the resistance to deformation,resulting in obvious release of dissipated energy and the reduction of bearing capacity.Conversely,after low-amplitude cyclic loading,both the pre-peak bearing capacity and the post-peak ductility of the pillar system increased due to the compaction of initial defects,indicating that the peak bearing capacity was closely related to the extent of pre-peak fatigue damage.The axial strain of each pillar was measured by DIC virtual extensometer to present the damage extent during cyclic loading phase.Meanwhile,fracture evolution of typical load drop points was also characterized by transverse strain fields(εxx),and observations showed that the damage extent of key pillar undergoing high-amplitude cyclic loads was more serious and violent,accompanied by the ejection of rock debris and loud noises.展开更多
The paper describes the concept of plaintext encryption by using the Unicode characters. In the case of elliptic curve cryptography, there is not specified rule or algorithm to specify the letters of Tifinagh as well ...The paper describes the concept of plaintext encryption by using the Unicode characters. In the case of elliptic curve cryptography, there is not specified rule or algorithm to specify the letters of Tifinagh as well as special characters. So, the paper gives the transformation of characters Tifinagh into points on elliptic curve by using the corresponding characters Latin. The obtained correspondence has been applied in Menezes-Vanstone cryptosystem based on elliptic curve. Therefore, the paper explains in detail its implementation in Maple 12.展开更多
This paper proposed a novel multi-view interactive behavior recognition method based on local self-similarity descriptors and graph shared multi-task learning. First, we proposed the composite interactive feature repr...This paper proposed a novel multi-view interactive behavior recognition method based on local self-similarity descriptors and graph shared multi-task learning. First, we proposed the composite interactive feature representation which encodes both the spatial distribution of local motion of interest points and their contexts. Furthermore, local self-similarity descriptor represented by temporal-pyramid bag of words(BOW) was applied to decreasing the influence of observation angle change on recognition and retaining the temporal information. For the purpose of exploring latent correlation between different interactive behaviors from different views and retaining specific information of each behaviors, graph shared multi-task learning was used to learn the corresponding interactive behavior recognition model. Experiment results showed the effectiveness of the proposed method in comparison with other state-of-the-art methods on the public databases CASIA, i3Dpose dataset and self-built database for interactive behavior recognition.展开更多
Image authentication techniques used to protect the recipients against malicious forgery. In this paper, we propose a new image authentication technique based on digital signature. The authentication is verified by co...Image authentication techniques used to protect the recipients against malicious forgery. In this paper, we propose a new image authentication technique based on digital signature. The authentication is verified by comparing the features of the each block in tested image with the corresponding features of the block recorded in the digital signature. The proposed authentication scheme is capable of distinguishing visible but non-malicious changes due to common processing operations from malicious changes. At last our experimental results show that the proposed scheme is not only efficient to protect integrity of image, but also with low computation, which are feasible for practical applications.展开更多
Anatolia peninsula that is a bridge between Asia and Europe has become a house for many diverse nations and settlement for over centuries because of its unprecedented strategic location above mentioned. Every newly-ar...Anatolia peninsula that is a bridge between Asia and Europe has become a house for many diverse nations and settlement for over centuries because of its unprecedented strategic location above mentioned. Every newly-arrived community seems to have captured the native features. Regardless looking what their origins or from where they come this Anatolian culture, local features of which overrides, takes its base from Anatolia's distinctive geopolitical location. Situated in the crossroads of world's most beautiful and important roads Anatolia has lots of different geographical features that are isolated from each other by chain of mountains and include many units. And this allowed the peninsula to have different cultural features in almost every period of history. In Anatolia that has a very dynamic history, one of the most important element changing in time is the name of places. Despite the fact that there is not a precision in the change of names, it is generally related with the language used by prevailing public.展开更多
A novel torsion sensor,which can be embedded in the engineering material,is proposed.Based on the coupled mode theory and the characteristic of twisted high birefringence fiber,we have established the mathematical mod...A novel torsion sensor,which can be embedded in the engineering material,is proposed.Based on the coupled mode theory and the characteristic of twisted high birefringence fiber,we have established the mathematical model of twisted high birefringence fiber grating transfer matrix.Two numerical simulation methods based on the transfer matrix method and coupled mode theory were used to analyze the consequent changes in reflection spectra.The simulation results of the two methods show good agreement with each other.The two main peak wavelengths of the high birefringence fiber grating shift as the twist angle changes from 0 to 360.And a peak was produced among the wavelengths of two main peaks.Its wavelength basically does not change and is about 1 552.225 nm.Its corresponding reflected peak value R_c basically presents the linear relationship with the twist angle α.The experiments show that the system has a wide measurement range.The resolution is 0.012° and the sensitivity is 0.13/rad.Good agreements between experimental results and numerical simulations have been obtained.展开更多
文摘A VQ based efficient speech recognition method is introduced, and the key parameters of this method are comparatively studied. This method is especially designed for mandarin speaker dependent small size word set recognition. It has less complexity, less resource consumption but higher ARR (accurate recognition rate) compared with traditional HMM or NN approach. A large scale test on the task of 11 mandarin digits recognition shows that the WER(word error rate) can reach 3 86%. This method is suitable for being embedded in PDA (personal digital assistant), mobile phone and so on to perform voice controlling like digits dialing, name dialing, calculating, voice commanding, etc.
文摘The design of an FPGA( field programmable gate array) based programmable SONET (synchronous optical network) OC-192 10 Gbit/s PRBS (pseudo-random binary sequence) generator and a bit interleaved polarity 8 (BIP-8) error detector is presented. Implemented in a parallel feedback configuration, this tester features PRBS generation of sequences with bit lengths of 2^7 - 1,2^10- 1,2^15 - 1,2^23 - land 2^31 - 1 for up to 10 Gbit/s applications with a 10 Gbit/s optical transceiver, via the SFI-4 (OC-192 serdes-framer interface). In the OC-192 frame alignment circuit, a dichotomy search algorithm logic which performs the functions of word alignment and STM-64/OC192 de-frame speeds up the frame sync logic and reduces circuit complexity greatly. The system can be used as a low cost tester to evaluate the performance of OC-192 devices and components, taking the replacement of precious commercial PRBS testers.
基金Project supported by the National Basic Research Program (973) of China (No. 2002-CB-312101) and the National Natural Science Foundation of China (No. 60773037)
文摘In this paper, a novel approach is proposed for denoising of Chinese calligraphy tablet documents. The method includes two phases: First, a partial differential equations (PDE) based the total variation model and Otsu thresholding method are used to preprocess the calligraphy document image. Second, a new method based on run-length statistics and structure charac- teristics of Chinese characters is proposed to remove some random and ant-like noises. This includes the optimal threshold se- lection from histogram of run-length probability density, and improved Hough transform algorithm for line shape noise detection and removal. Examples are given in the paper to demonstrate the proposed method.
基金Project supported by the OMRON and SJTU Collaborative Founda-tion under PVS project (2005.03~2005.10)
文摘This paper proposes a learning-based method for text detection and text segmentation in natural scene images. First, the input image is decomposed into multiple connected-components (CCs) by Niblack clustering algorithm. Then all the CCs including text CCs and non-text CCs are verified on their text features by a 2-stage classification module, where most non-text CCs are discarded by an attentional cascade classifier and remaining CCs are further verified by an SVM. All the accepted CCs are output to result in text only binary image. Experiments with many images in different scenes showed satisfactory performance of our proposed method.
文摘Some important tidal features of 8 major tidal constituents ( M 2, S 2, K 1, O 1, P 1, Sa, N 2 and K 2 ) in the China Seas and their adjacent sea areas were obtained using six years’ TOPEX/POSEIDON altimeter data. The results showed that the obtained co tidal and co range charts for these major tidal constituents agreed well with those of previous researches using observational data from coastal tidal gauge stations and numerical models.
基金funding by the National Natural Science Foundation of China(Nos.51474039 and 51404046)the Project of Shanxi Provincial Federation of Coalbed Methane Research(No.2013012010)the Science Foundation of North University of China(No.XJJ2016033)
文摘To accurately describe damage within coal, digital image processing technology was used to determine texture parameters and obtain quantitative information related to coal meso-cracks. The relationship between damage and mesoscopic information for coal under compression was then analysed. The shape and distribution of damage were comprehensively considered in a defined damage variable, which was based on the texture characteristic. An elastic-brittle damage model based on the mesostructure information of coal was established. As a result, the damage model can appropriately and reliably replicate the processes of initiation, expansion, cut-through and eventual destruction of microscopic damage to coal under compression. After comparison, it was proved that the predicted overall stress-strain response of the model was comparable to the experimental result.
基金The National Natural Science Foundation of China(No.61603091)。
文摘In order to improve the detection accuracy of small objects,a neighborhood fusion-based hierarchical parallel feature pyramid network(NFPN)is proposed.Unlike the layer-by-layer structure adopted in the feature pyramid network(FPN)and deconvolutional single shot detector(DSSD),where the bottom layer of the feature pyramid network relies on the top layer,NFPN builds the feature pyramid network with no connections between the upper and lower layers.That is,it only fuses shallow features on similar scales.NFPN is highly portable and can be embedded in many models to further boost performance.Extensive experiments on PASCAL VOC 2007,2012,and COCO datasets demonstrate that the NFPN-based SSD without intricate tricks can exceed the DSSD model in terms of detection accuracy and inference speed,especially for small objects,e.g.,4%to 5%higher mAP(mean average precision)than SSD,and 2%to 3%higher mAP than DSSD.On VOC 2007 test set,the NFPN-based SSD with 300×300 input reaches 79.4%mAP at 34.6 frame/s,and the mAP can raise to 82.9%after using the multi-scale testing strategy.
基金The National Natural Science Foundation of China (No. 40375036) the Base Condition Flat Roof Item of the Ministry of Science and Technology (No.2003DIB4J145)
文摘With PSU/NCAR nonhydrostatic mesoscale model MM5, the rainfall process of tropical storm Fitow(0114) is simulated for 00:00 UTC 31 Aug. – 00:00 UTC 2 Sept. 2001. Mesoscale separation is performed on the results with the filtering scheme. Analyses show that the MM5 model well reproduced the position and intensity of heavy rain. Mesoscale characteristics of heavy rain were well represented in rainfall time scale, rainfall area, stream field and divergence at lower and upper levels. The interaction between inverted typhoon troughs and the mesoscale systems lead to heavy rain occurrence. The distribution of divergence fields at lower and upper levels can have a kind of indication for the rainfall. Heavy rains are closely associated with topography and land-sea distribution in South China. Weak instability is favorable to the generation of heavy rain.
基金funded by the International Co-operation Program of the Ministry of Science and Technology of China (Grant No. 2010DFA92720)the Project of the National Eleventh-Five Year Research Program of China (Grant No. 2012BAC19B07)
文摘As a component of streamflow, baseflow is critical for regulating seasonal distribution of river fows and stabilizing water supplies. Water resources in the arid area of Northwest China are mainly from multiple catchments in the alpine that could be influenced by varieties of climatic, land cover, soil and geological factors. While numerous studies have been done on streamflow, systematic analysis of baseflow in the alpine river systems is scare. Based on historical daily streamflow data and the automated digital filter method of baseflow separation, this study investigated characteristics of hydrographs of overland flow, streamflow and baseflowof river systems fed by rainfall, snowmelt, glacier melt or mixtures of these. This study also calculated the recession constants and baseflow indices of 65 river systems. While the recession constant was o.oo34- o.o728 with a mean of o.o18, the baseflow index was 0.27-0.79 with a mean of 0.57. Further, Spearman's correlation analysis showed that the baseflow index was significantly correlated with catchment climatic factors (e.g., precipitation and temperature), topographic factors (e.g., elevation and slope) and aquifer properties represented by the recession constant. Multiple regression analysis indicated that the factors explained 65% of the variability of baseflow index in the studv area.
文摘This paper discusses a neglected theme in Wittgenstein's writings on meaning and psychology from the early 1930s until 1949. Throughout this period Wittgenstein deals with aspects of meaning of words and pictures that cannot be accounted for in dispositional terms but have to be related to experience and perception. Wittgenstein's reading of William James, I argue, has sharpened his eye for the many pitfalls in coming to terms with this experiential notion of meaning. James's treatment of experiences of meaning succumbs to the temptation to postulate ~~meaning-bodies," bearers of meaning apart from the way and context in which we use the particular words. I argue that the conflation of what Wittgenstein calls the transitive and intransitive use of words is at the root of postulating meaning-bodies. I also argue that contemporary treatments of experiences of meaning are similarly vulnerable to James's confusion.
文摘In photogrammetry and remote sensing, image matching is a basic and crucial process for automatic DEM generation. In this paper we presented a image relaxation matching method based on feature points. This method can be considered as an extention of regular grid point based matching. It avoids the shortcome of grid point based matching. For example, with this method, we can avoid low or even no texture area where errors frequently appear in cross correlaton matching. In the mean while, it makes full use of some mature techniques such as probability relaxation, image pyramid and the like which have already been successfully used in grid point matching process. Application of the technique to DEM generaton in different regions proved that it is more reasonable and reliable.
文摘Character derivation means that if a graph represents several meanings, a new graph based on the original one will be created to bear one or two of the meanings, which is a natural law in Chinese writing system. The old graph is called original character, and the new generated one is called derived character. Two kinds of phenomena-derivation of cognate words (同詞孳乳) and differentiation of unidentical words (異詞別異)-promote the derivation of Chinese characters. In return, derived characters not only bear meaning of the original one, but also serve as a symbol of an independent word and consolidate the graph-meaning relationship. It deserves much attention to the law of the process of character derivation.
文摘By the use of cross-correlation measures, the response of a symmetric Schmitt trigger (ST) driven by a random binary signal and white Gaussian noise is investigated. The results show that the information transmission can be enhanced when a certain amount of noise is presented, i.e., aperiodic stochastic resonance (ASR). Then, the influence of signal amplitude and the ST threshold on ASR is examined, the applicability of the ST in reducing the noise level of random signal transmission and improving the quality of output signal via ASR effect is illustrated. This research is of great interest in the field of digital communications.
基金Project(2015CB060200)supported by the National Basic Research Program of ChinaProject(41772313)supported by the National Natural Science Foundation of ChinaProject(2017zzts185)supported by the Fundamental Research Funds for the Central Universities,China
文摘Aiming to investigate the fatigue damage mechanism and bearing characteristics of multi-pillar system under cyclic loading,a series of axial cyclic loading tests with different cyclic amplitudes were carried out on triple-pillar marble specimens.The acoustic emission(AE)and digital image correlation(DIC)were jointly applied to monitoring and recording damage evolution and failure behavior of each pillar,which reproduced the cataclysmic instability process of underground pillar groups.Experimental results indicated that the cyclic amplitude exceeding the threshold of damage initiation weakened the resistance to deformation,resulting in obvious release of dissipated energy and the reduction of bearing capacity.Conversely,after low-amplitude cyclic loading,both the pre-peak bearing capacity and the post-peak ductility of the pillar system increased due to the compaction of initial defects,indicating that the peak bearing capacity was closely related to the extent of pre-peak fatigue damage.The axial strain of each pillar was measured by DIC virtual extensometer to present the damage extent during cyclic loading phase.Meanwhile,fracture evolution of typical load drop points was also characterized by transverse strain fields(εxx),and observations showed that the damage extent of key pillar undergoing high-amplitude cyclic loads was more serious and violent,accompanied by the ejection of rock debris and loud noises.
文摘The paper describes the concept of plaintext encryption by using the Unicode characters. In the case of elliptic curve cryptography, there is not specified rule or algorithm to specify the letters of Tifinagh as well as special characters. So, the paper gives the transformation of characters Tifinagh into points on elliptic curve by using the corresponding characters Latin. The obtained correspondence has been applied in Menezes-Vanstone cryptosystem based on elliptic curve. Therefore, the paper explains in detail its implementation in Maple 12.
基金Project(51678075)supported by the National Natural Science Foundation of ChinaProject(2017GK2271)supported by Hunan Provincial Science and Technology Department,China
文摘This paper proposed a novel multi-view interactive behavior recognition method based on local self-similarity descriptors and graph shared multi-task learning. First, we proposed the composite interactive feature representation which encodes both the spatial distribution of local motion of interest points and their contexts. Furthermore, local self-similarity descriptor represented by temporal-pyramid bag of words(BOW) was applied to decreasing the influence of observation angle change on recognition and retaining the temporal information. For the purpose of exploring latent correlation between different interactive behaviors from different views and retaining specific information of each behaviors, graph shared multi-task learning was used to learn the corresponding interactive behavior recognition model. Experiment results showed the effectiveness of the proposed method in comparison with other state-of-the-art methods on the public databases CASIA, i3Dpose dataset and self-built database for interactive behavior recognition.
文摘Image authentication techniques used to protect the recipients against malicious forgery. In this paper, we propose a new image authentication technique based on digital signature. The authentication is verified by comparing the features of the each block in tested image with the corresponding features of the block recorded in the digital signature. The proposed authentication scheme is capable of distinguishing visible but non-malicious changes due to common processing operations from malicious changes. At last our experimental results show that the proposed scheme is not only efficient to protect integrity of image, but also with low computation, which are feasible for practical applications.
文摘Anatolia peninsula that is a bridge between Asia and Europe has become a house for many diverse nations and settlement for over centuries because of its unprecedented strategic location above mentioned. Every newly-arrived community seems to have captured the native features. Regardless looking what their origins or from where they come this Anatolian culture, local features of which overrides, takes its base from Anatolia's distinctive geopolitical location. Situated in the crossroads of world's most beautiful and important roads Anatolia has lots of different geographical features that are isolated from each other by chain of mountains and include many units. And this allowed the peninsula to have different cultural features in almost every period of history. In Anatolia that has a very dynamic history, one of the most important element changing in time is the name of places. Despite the fact that there is not a precision in the change of names, it is generally related with the language used by prevailing public.
基金Supported by National Natural Science Foundation of China(60377002)
文摘A novel torsion sensor,which can be embedded in the engineering material,is proposed.Based on the coupled mode theory and the characteristic of twisted high birefringence fiber,we have established the mathematical model of twisted high birefringence fiber grating transfer matrix.Two numerical simulation methods based on the transfer matrix method and coupled mode theory were used to analyze the consequent changes in reflection spectra.The simulation results of the two methods show good agreement with each other.The two main peak wavelengths of the high birefringence fiber grating shift as the twist angle changes from 0 to 360.And a peak was produced among the wavelengths of two main peaks.Its wavelength basically does not change and is about 1 552.225 nm.Its corresponding reflected peak value R_c basically presents the linear relationship with the twist angle α.The experiments show that the system has a wide measurement range.The resolution is 0.012° and the sensitivity is 0.13/rad.Good agreements between experimental results and numerical simulations have been obtained.