Pub Date : 1991-05-09DOI: 10.1109/PACRIM.1991.160752
R. Schaphorst, J. Roth
A description is presented of three different techniques for measuring motion distortion in video teleconferencing and videophone (VTC/VP) systems: temporal frequency response, scene cut response, and transmitted frame rate. All three techniques satisfy the two basic requisites for a measurement procedure to be practical. First, the measurements are performed using only the output processed picture. Second, the techniques for generating the test signal and analyzing the output signal are not excessively complex so there is promise of developing practical test equipment to implement the test procedure.<>
{"title":"Techniques for objectively measuring motion distortion in video teleconferencing systems","authors":"R. Schaphorst, J. Roth","doi":"10.1109/PACRIM.1991.160752","DOIUrl":"https://doi.org/10.1109/PACRIM.1991.160752","url":null,"abstract":"A description is presented of three different techniques for measuring motion distortion in video teleconferencing and videophone (VTC/VP) systems: temporal frequency response, scene cut response, and transmitted frame rate. All three techniques satisfy the two basic requisites for a measurement procedure to be practical. First, the measurements are performed using only the output processed picture. Second, the techniques for generating the test signal and analyzing the output signal are not excessively complex so there is promise of developing practical test equipment to implement the test procedure.<<ETX>>","PeriodicalId":289986,"journal":{"name":"[1991] IEEE Pacific Rim Conference on Communications, Computers and Signal Processing Conference Proceedings","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1991-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121792480","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1991-05-09DOI: 10.1109/PACRIM.1991.160845
Chen Yi, Fu Yuqing, Fei Zhong
An approach for extracting human body in motion images from a real world scene is presented. It is based on accumulating several difference pictures to recover a moving human body. In difference operations, a technique is proposed to threshold the difference picture, in which an exponential data fitting method is applied to histogram analysis. Then a region-based classification which works on the principle of maximizing the between-class variance is performed to remove the static background that survived. Experimental results show that, owing to utilization of more motion information contained in the sequence, the proposed approach produces a robust and efficient segmentation by only two simple operations of difference and accumulation.<>
{"title":"Accumulative difference method for human body motion segmentation in a real-world scene","authors":"Chen Yi, Fu Yuqing, Fei Zhong","doi":"10.1109/PACRIM.1991.160845","DOIUrl":"https://doi.org/10.1109/PACRIM.1991.160845","url":null,"abstract":"An approach for extracting human body in motion images from a real world scene is presented. It is based on accumulating several difference pictures to recover a moving human body. In difference operations, a technique is proposed to threshold the difference picture, in which an exponential data fitting method is applied to histogram analysis. Then a region-based classification which works on the principle of maximizing the between-class variance is performed to remove the static background that survived. Experimental results show that, owing to utilization of more motion information contained in the sequence, the proposed approach produces a robust and efficient segmentation by only two simple operations of difference and accumulation.<<ETX>>","PeriodicalId":289986,"journal":{"name":"[1991] IEEE Pacific Rim Conference on Communications, Computers and Signal Processing Conference Proceedings","volume":"113 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1991-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124178551","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1991-05-09DOI: 10.1109/PACRIM.1991.160835
Z. Ulman, M. Czyzak, J. Zurada
A residue division technique is presented. The technique is based on the use of a number system termed the radix-based residue number system (RNS) and, associated with it, the homogeneous mixed-radix number system (HMRS). The quotient is obtained as the sum of the rounded partial quotients of the HMRS weights and the divisor. The division is fast, noniterative, and implementable in a parallel look-up table based architecture. Contrary to binary division by right shifting, the division time is fixed and independent of the divisor value.<>
{"title":"Fast division in residue arithmetic","authors":"Z. Ulman, M. Czyzak, J. Zurada","doi":"10.1109/PACRIM.1991.160835","DOIUrl":"https://doi.org/10.1109/PACRIM.1991.160835","url":null,"abstract":"A residue division technique is presented. The technique is based on the use of a number system termed the radix-based residue number system (RNS) and, associated with it, the homogeneous mixed-radix number system (HMRS). The quotient is obtained as the sum of the rounded partial quotients of the HMRS weights and the divisor. The division is fast, noniterative, and implementable in a parallel look-up table based architecture. Contrary to binary division by right shifting, the division time is fixed and independent of the divisor value.<<ETX>>","PeriodicalId":289986,"journal":{"name":"[1991] IEEE Pacific Rim Conference on Communications, Computers and Signal Processing Conference Proceedings","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1991-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129026055","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1991-05-09DOI: 10.1109/PACRIM.1991.160828
M. A. Hasan, J. Lee, V. Bhargava
In the presence of strong jamming signals, the use of interference cancellers with spread-spectrum modulation has proved to be effective in providing a sufficient degree of interference rejection capability in data transmission systems. An adaptive interference canceller with an adjustable center weight is proposed to improve the performance of the conventional canceller. The input signal of the canceller is assumed to consist of the data, interference, and additive white Gaussian noise. The results obtained can readily be applied to data transmission systems such as normal binary phase shift keying (BPSK) and direct-sequence spread-spectrum BPSK modems. The performance of the interference canceller is shown to be better than the conventional canceller by analysis and computer simulations.<>
{"title":"Performance of a narrowband interference canceller with an adjustable center weight","authors":"M. A. Hasan, J. Lee, V. Bhargava","doi":"10.1109/PACRIM.1991.160828","DOIUrl":"https://doi.org/10.1109/PACRIM.1991.160828","url":null,"abstract":"In the presence of strong jamming signals, the use of interference cancellers with spread-spectrum modulation has proved to be effective in providing a sufficient degree of interference rejection capability in data transmission systems. An adaptive interference canceller with an adjustable center weight is proposed to improve the performance of the conventional canceller. The input signal of the canceller is assumed to consist of the data, interference, and additive white Gaussian noise. The results obtained can readily be applied to data transmission systems such as normal binary phase shift keying (BPSK) and direct-sequence spread-spectrum BPSK modems. The performance of the interference canceller is shown to be better than the conventional canceller by analysis and computer simulations.<<ETX>>","PeriodicalId":289986,"journal":{"name":"[1991] IEEE Pacific Rim Conference on Communications, Computers and Signal Processing Conference Proceedings","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1991-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131201379","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1991-05-09DOI: 10.1109/PACRIM.1991.160795
S. Massoumi, S. Kallel
An adaptive scheme for trellis coded modulation of multiple phase shift keying (MPSK) signals, called adaptive trellis coded MPSK (ATCMPSK), is proposed for the Rayleigh fading channel. The adaptive scheme is based on varying the coding/modulation (codulation) rate according to channel conditions. Slow fading and ideal channel information at the receiver are assumed. It is shown that ATCMPSK results in a considerable improvement in bit error rate (BER) performance of MPSK signals under fading.<>
{"title":"Adaptive trellis coded modulation for mobile communications","authors":"S. Massoumi, S. Kallel","doi":"10.1109/PACRIM.1991.160795","DOIUrl":"https://doi.org/10.1109/PACRIM.1991.160795","url":null,"abstract":"An adaptive scheme for trellis coded modulation of multiple phase shift keying (MPSK) signals, called adaptive trellis coded MPSK (ATCMPSK), is proposed for the Rayleigh fading channel. The adaptive scheme is based on varying the coding/modulation (codulation) rate according to channel conditions. Slow fading and ideal channel information at the receiver are assumed. It is shown that ATCMPSK results in a considerable improvement in bit error rate (BER) performance of MPSK signals under fading.<<ETX>>","PeriodicalId":289986,"journal":{"name":"[1991] IEEE Pacific Rim Conference on Communications, Computers and Signal Processing Conference Proceedings","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1991-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129532944","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1991-05-09DOI: 10.1109/PACRIM.1991.160859
D. Noel, G. Dew, S. Kumar, M. Fiala-Timlin, K. Mann
The 1200/8000 b/s GMSK-like modem utilizing a digital signal processor (DSP) and the required support circuitry is being developed. The modem functions are implemented using a DSP-based assembler. Both data transmission speeds are accommodated and are user selectable depending upon the position of a hardware selection switch (prototype only). The design eliminates the need for external DSP memory, as both the transmit and receive software, each restricted in size to 512 words of 24 bits, will reside on the DSP while being used. The DSP forms the heart of the modem. The controller section makes use of an Intel microprocessor, RAM, PROM, EEPROM, a gate array to provide an interface to the radio, and a combination of a communications controller with EIA drivers to create a standard user terminal interface.<>
{"title":"The development of an 8 kbps GMSK-like modem for Mobitex","authors":"D. Noel, G. Dew, S. Kumar, M. Fiala-Timlin, K. Mann","doi":"10.1109/PACRIM.1991.160859","DOIUrl":"https://doi.org/10.1109/PACRIM.1991.160859","url":null,"abstract":"The 1200/8000 b/s GMSK-like modem utilizing a digital signal processor (DSP) and the required support circuitry is being developed. The modem functions are implemented using a DSP-based assembler. Both data transmission speeds are accommodated and are user selectable depending upon the position of a hardware selection switch (prototype only). The design eliminates the need for external DSP memory, as both the transmit and receive software, each restricted in size to 512 words of 24 bits, will reside on the DSP while being used. The DSP forms the heart of the modem. The controller section makes use of an Intel microprocessor, RAM, PROM, EEPROM, a gate array to provide an interface to the radio, and a combination of a communications controller with EIA drivers to create a standard user terminal interface.<<ETX>>","PeriodicalId":289986,"journal":{"name":"[1991] IEEE Pacific Rim Conference on Communications, Computers and Signal Processing Conference Proceedings","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1991-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129980190","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1991-05-09DOI: 10.1109/PACRIM.1991.160841
W. Little, P. Baker, D. Fraser, J. Aune, B. Sauder
The authors describe array-tag technology and its application in the forest industry. Array tag technology uses 2-D printed tag symbols consisting of an array of cells and tag readers consisting of a lens system and a video camera interfaced via a frame grabber to an image processing computer. The authors outline various array tag configurations, tag materials, and printing options. They describe the computer hardware and software image processing algorithms, and optical subsystems of array tag readers. In addition, example additions of the technology to lumber and log tracking and inventory control are discussed.<>
{"title":"Array tags in forestry","authors":"W. Little, P. Baker, D. Fraser, J. Aune, B. Sauder","doi":"10.1109/PACRIM.1991.160841","DOIUrl":"https://doi.org/10.1109/PACRIM.1991.160841","url":null,"abstract":"The authors describe array-tag technology and its application in the forest industry. Array tag technology uses 2-D printed tag symbols consisting of an array of cells and tag readers consisting of a lens system and a video camera interfaced via a frame grabber to an image processing computer. The authors outline various array tag configurations, tag materials, and printing options. They describe the computer hardware and software image processing algorithms, and optical subsystems of array tag readers. In addition, example additions of the technology to lumber and log tracking and inventory control are discussed.<<ETX>>","PeriodicalId":289986,"journal":{"name":"[1991] IEEE Pacific Rim Conference on Communications, Computers and Signal Processing Conference Proceedings","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1991-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128713069","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1991-05-09DOI: 10.1109/PACRIM.1991.160763
S. Foda, P. Agathoklis
An algebraic test for asymptotic stability independent of delay for delay differential systems is presented. The test is developed using the Kronecker product formulation of the frequency dependent Lyapunov equation for delay differential systems. Sufficient conditions for asymptotic stability independent of delay are shown to be equivalent to testing the eigenvalues of a set of constant matrices. Numerical aspects of the algorithms are also discussed.<>
{"title":"An algebraic test for asymptotic stability of delay differential systems with commensurate delays","authors":"S. Foda, P. Agathoklis","doi":"10.1109/PACRIM.1991.160763","DOIUrl":"https://doi.org/10.1109/PACRIM.1991.160763","url":null,"abstract":"An algebraic test for asymptotic stability independent of delay for delay differential systems is presented. The test is developed using the Kronecker product formulation of the frequency dependent Lyapunov equation for delay differential systems. Sufficient conditions for asymptotic stability independent of delay are shown to be equivalent to testing the eigenvalues of a set of constant matrices. Numerical aspects of the algorithms are also discussed.<<ETX>>","PeriodicalId":289986,"journal":{"name":"[1991] IEEE Pacific Rim Conference on Communications, Computers and Signal Processing Conference Proceedings","volume":"90 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1991-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124282928","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1991-05-09DOI: 10.1109/PACRIM.1991.160868
S. A. Altekar, N. Beaulieu
The authors derive some upper bounds to the error probability of decision feedback equalization (DFE). The bounds are valid for the same conditions as the bounds of D.L. Duttweiler et al. (1974). The bounds are as much as 2.8 dB tighter in signal-to-noise ratio (SNR) than those of Duttweiler for certain channels. An upper bound based on considering distinct single error states is derived. A second bound based on examining distinct single and distinct double consecutive error states is presented. Worthwhile improvement over the second bound is obtained by adding all distinct double error states to the reduced state model. Triple consecutive error state bounds are considered, and a revised comparison of DFE with linear equalization is made using the tighter bounds.<>
{"title":"Tight upper bounds to the error probability of decision feedback equalization","authors":"S. A. Altekar, N. Beaulieu","doi":"10.1109/PACRIM.1991.160868","DOIUrl":"https://doi.org/10.1109/PACRIM.1991.160868","url":null,"abstract":"The authors derive some upper bounds to the error probability of decision feedback equalization (DFE). The bounds are valid for the same conditions as the bounds of D.L. Duttweiler et al. (1974). The bounds are as much as 2.8 dB tighter in signal-to-noise ratio (SNR) than those of Duttweiler for certain channels. An upper bound based on considering distinct single error states is derived. A second bound based on examining distinct single and distinct double consecutive error states is presented. Worthwhile improvement over the second bound is obtained by adding all distinct double error states to the reduced state model. Triple consecutive error state bounds are considered, and a revised comparison of DFE with linear equalization is made using the tighter bounds.<<ETX>>","PeriodicalId":289986,"journal":{"name":"[1991] IEEE Pacific Rim Conference on Communications, Computers and Signal Processing Conference Proceedings","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1991-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126733208","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1991-05-09DOI: 10.1109/PACRIM.1991.160755
T. Calvert, J. Dickinson, J. Dill, W. Havens, J. Jones, L. Bartram
A description is presented of the first steps towards an intelligent CAD system based on a mixed-initiative approach. The expert system is an object-oriented model-based reasoning engine using constraint propagation and dependency backtracking. The architecture is built around the expert system, a CAD engine, and a user interface/controller module mediating the mixed-initiative relationship between designer and system. Initial experience has shown the need to model both experts and objects in the knowledge base and both the need and difficulty of representing design and constraint spaces to the designer. The preliminary results of a study of how people use a CAD system to better understand the design process itself suggest directions for the development of intelligent CAD.<>
{"title":"An intelligent basis for design","authors":"T. Calvert, J. Dickinson, J. Dill, W. Havens, J. Jones, L. Bartram","doi":"10.1109/PACRIM.1991.160755","DOIUrl":"https://doi.org/10.1109/PACRIM.1991.160755","url":null,"abstract":"A description is presented of the first steps towards an intelligent CAD system based on a mixed-initiative approach. The expert system is an object-oriented model-based reasoning engine using constraint propagation and dependency backtracking. The architecture is built around the expert system, a CAD engine, and a user interface/controller module mediating the mixed-initiative relationship between designer and system. Initial experience has shown the need to model both experts and objects in the knowledge base and both the need and difficulty of representing design and constraint spaces to the designer. The preliminary results of a study of how people use a CAD system to better understand the design process itself suggest directions for the development of intelligent CAD.<<ETX>>","PeriodicalId":289986,"journal":{"name":"[1991] IEEE Pacific Rim Conference on Communications, Computers and Signal Processing Conference Proceedings","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1991-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127185711","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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