An enhanced digital radiograph is obtained by multiplication between the digital radiograph and the digital Fourier transform of the second derivative of the Gaussian function ( Delta /sup 2/g) and inverse transformation, and the subsequent histogram equalization. Because image data includes only real values, the purely real-numbered transform, called the fast Hartley transform (FHT) is used to perform a digital Fourier transform of the image data. Preliminary results suggest that the transform of the Laplacian of the Gaussian may provide a more effective edge enhancement for medical imagery than space-domain convolution techniques such as the Sobel operator.<>
{"title":"Transform domain edge enhancement of digital radiographs","authors":"Paik Chul Hwa, M. Fox","doi":"10.1109/NEBC.1988.19410","DOIUrl":"https://doi.org/10.1109/NEBC.1988.19410","url":null,"abstract":"An enhanced digital radiograph is obtained by multiplication between the digital radiograph and the digital Fourier transform of the second derivative of the Gaussian function ( Delta /sup 2/g) and inverse transformation, and the subsequent histogram equalization. Because image data includes only real values, the purely real-numbered transform, called the fast Hartley transform (FHT) is used to perform a digital Fourier transform of the image data. Preliminary results suggest that the transform of the Laplacian of the Gaussian may provide a more effective edge enhancement for medical imagery than space-domain convolution techniques such as the Sobel operator.<<ETX>>","PeriodicalId":165980,"journal":{"name":"Proceedings of the 1988 Fourteenth Annual Northeast Bioengineering Conference","volume":"81 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122901357","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}
The optical configuration of the presented sensor consists of three imaging lenses mounted on a pair of eyeglass frames around the field of vision. This allows normal eye movement and unobstructed vision without distracting the subject. The optical sensors gather light reflected from the area of the sclera to the immediate left and right of the iris and transmit this light through optical fibers to remote detectors. The device determines horizontal position by utilizing the difference in reflectivity between the iris and sclera. Vertical position of the eye is determined similarly by monitoring either the upper or lower eyelid. Point-of-gaze and short period tracking measurements have been made in two dimensions with an accuracy of better than half a degree in the horizontal direction and three degrees in the vertical direction.<>
{"title":"A two dimensional fiber optic eye position sensor for tracking and point-of-gaze measurements","authors":"D.C. Johnson, D.M. Drouin, A. Drake","doi":"10.1109/NEBC.1988.19330","DOIUrl":"https://doi.org/10.1109/NEBC.1988.19330","url":null,"abstract":"The optical configuration of the presented sensor consists of three imaging lenses mounted on a pair of eyeglass frames around the field of vision. This allows normal eye movement and unobstructed vision without distracting the subject. The optical sensors gather light reflected from the area of the sclera to the immediate left and right of the iris and transmit this light through optical fibers to remote detectors. The device determines horizontal position by utilizing the difference in reflectivity between the iris and sclera. Vertical position of the eye is determined similarly by monitoring either the upper or lower eyelid. Point-of-gaze and short period tracking measurements have been made in two dimensions with an accuracy of better than half a degree in the horizontal direction and three degrees in the vertical direction.<<ETX>>","PeriodicalId":165980,"journal":{"name":"Proceedings of the 1988 Fourteenth Annual Northeast Bioengineering Conference","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114713646","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}
An output feedback controller for the Penn State rollerscrew electric ventricular assist device (EVAD) is discussed. The controller minimizes the electrical energy consumption while using the only observable state variable as its signal. The initial conditions on which the optimal control of the EVAD depends are based on cardiovascular data of the general population. Comparison of the Rollerscrew EVAD with the Cam EVAD reveals a striking difference in efficiency between the two devices. A patient with an optimally controlled Rollerscrew EVAD could function for 14.5 h without a recharge while the same patient with an optimally controlled Cam EVAD could function only for 8 h.<>
{"title":"Minimal power consumption of the Penn State rollerscrew EVAD through optimal and suboptimal control","authors":"G. Klute, U. Tsach, D. Geselowitz","doi":"10.1109/NEBC.1988.19347","DOIUrl":"https://doi.org/10.1109/NEBC.1988.19347","url":null,"abstract":"An output feedback controller for the Penn State rollerscrew electric ventricular assist device (EVAD) is discussed. The controller minimizes the electrical energy consumption while using the only observable state variable as its signal. The initial conditions on which the optimal control of the EVAD depends are based on cardiovascular data of the general population. Comparison of the Rollerscrew EVAD with the Cam EVAD reveals a striking difference in efficiency between the two devices. A patient with an optimally controlled Rollerscrew EVAD could function for 14.5 h without a recharge while the same patient with an optimally controlled Cam EVAD could function only for 8 h.<<ETX>>","PeriodicalId":165980,"journal":{"name":"Proceedings of the 1988 Fourteenth Annual Northeast Bioengineering Conference","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125567023","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}
Electrocardiography (ECG) monitoring during electrosurgery may become greatly distorted from the interference of the radio-frequency (RF) signals generated by the electrosurgical unit. A solution to this problem is discussed. In the ECG sampling unit the RF function generator used to drive an RF power amplifier for the cutting signal for the wand is controlled in such a way that a sample of the ECG is taken while the generator is off. This is done without significantly altering the cutting signal.<>
{"title":"ECG sampling unit for electrosurgical environments","authors":"G.T. Jankauskas, J. Lacourse, S. Selikowitz","doi":"10.1109/NEBC.1988.19348","DOIUrl":"https://doi.org/10.1109/NEBC.1988.19348","url":null,"abstract":"Electrocardiography (ECG) monitoring during electrosurgery may become greatly distorted from the interference of the radio-frequency (RF) signals generated by the electrosurgical unit. A solution to this problem is discussed. In the ECG sampling unit the RF function generator used to drive an RF power amplifier for the cutting signal for the wand is controlled in such a way that a sample of the ECG is taken while the generator is off. This is done without significantly altering the cutting signal.<<ETX>>","PeriodicalId":165980,"journal":{"name":"Proceedings of the 1988 Fourteenth Annual Northeast Bioengineering Conference","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122299346","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}
Experimental testing of a prototype knowledge-based message generation system (KMGS) is discussed. The test was conducted to better understand the potential of the use of artificial intelligence (AI) techniques in the development of a nonvocal communication device. The communication rate of the system with respect to user's motor ability, system's scanning tolerance, and the use of both fixed statistical information and dynamic speech information are examined. Test results and discussions are presented.<>
{"title":"Experimental testing of an AI-based communication aid","authors":"B.K. Sy, J. Deller","doi":"10.1109/NEBC.1988.19371","DOIUrl":"https://doi.org/10.1109/NEBC.1988.19371","url":null,"abstract":"Experimental testing of a prototype knowledge-based message generation system (KMGS) is discussed. The test was conducted to better understand the potential of the use of artificial intelligence (AI) techniques in the development of a nonvocal communication device. The communication rate of the system with respect to user's motor ability, system's scanning tolerance, and the use of both fixed statistical information and dynamic speech information are examined. Test results and discussions are presented.<<ETX>>","PeriodicalId":165980,"journal":{"name":"Proceedings of the 1988 Fourteenth Annual Northeast Bioengineering Conference","volume":"381 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134502625","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}
While cooccurrence matrices have been shown to be helpful in quantitating image texture, the amount of data associated with them can rapidly become unmanageable because a separate cooccurrence matrix can be calculated for each displacement vector chosen. Here, a method for choosing the direction of the displacement vector that is based on the most dominant edge obtained from gradient analysis is discussed. Also, the anatomy of the liver is used to suggest the most important intersample spacing in constructing cooccurrence matrices for the evaluation of diffuse liver disease.<>
{"title":"Effect of cooccurrence displacement vector on quantitating ultrasonic image texture","authors":"J. DaPonte, J. Gelber, M. Fox","doi":"10.1109/NEBC.1988.19411","DOIUrl":"https://doi.org/10.1109/NEBC.1988.19411","url":null,"abstract":"While cooccurrence matrices have been shown to be helpful in quantitating image texture, the amount of data associated with them can rapidly become unmanageable because a separate cooccurrence matrix can be calculated for each displacement vector chosen. Here, a method for choosing the direction of the displacement vector that is based on the most dominant edge obtained from gradient analysis is discussed. Also, the anatomy of the liver is used to suggest the most important intersample spacing in constructing cooccurrence matrices for the evaluation of diffuse liver disease.<<ETX>>","PeriodicalId":165980,"journal":{"name":"Proceedings of the 1988 Fourteenth Annual Northeast Bioengineering Conference","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134646013","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}
Vascular tissue O/sub 2/ partial pressure (PO/sub 2/) measurements with recessed cathode O/sub 2/ microelectrodes were made in the walls of isolated rabbit abdominal aortas during saline perfusion in vitro. Three months prior to the experiments, the aortic lumen was reduced by approximately 50% using a tantalum metal clip. A 2- to 3-cm segment of the abdominal aorta including the stenosis was removed and mounted in a chamber maintained at 19.9 kPa. With constant perfusion, the minimum tissue PO/sub 2/ in the wall varied axially along the segment. The minimum wall PO/sub 2/ (+or-SE) was 13.5+or-0.4 kPa at the location 5 mm upstream and 14.2+or-0.8 kPa at the location 5 mm downstream. The lowest value, 11.6+or-0.8 kPa, was found 1 mm downstream. O/sub 2/ disappearance rates (dPO/sub 2//dt) at each location were also measured after stopping perfusion to the segment. The disappearance rates varied axially, with the fastest rate, -4.1+or-0.6 kPa/min, found 1 mm upstream. At 4 and 5 mm upstream and downstream from the stenosis, the rates were essentially the same, at 2.8+or-0.3 kPa/min. The average value for O/sub 2/ metabolism at the upstream and downstream ends is 5.0*10/sup -4/ mL O/sub 2//mL tissue/min.<>
{"title":"O/sub 2/ metabolism in blood vessel walls with stenoses","authors":"D. Buerk, S. Dubin, K. Gealow","doi":"10.1109/NEBC.1988.19387","DOIUrl":"https://doi.org/10.1109/NEBC.1988.19387","url":null,"abstract":"Vascular tissue O/sub 2/ partial pressure (PO/sub 2/) measurements with recessed cathode O/sub 2/ microelectrodes were made in the walls of isolated rabbit abdominal aortas during saline perfusion in vitro. Three months prior to the experiments, the aortic lumen was reduced by approximately 50% using a tantalum metal clip. A 2- to 3-cm segment of the abdominal aorta including the stenosis was removed and mounted in a chamber maintained at 19.9 kPa. With constant perfusion, the minimum tissue PO/sub 2/ in the wall varied axially along the segment. The minimum wall PO/sub 2/ (+or-SE) was 13.5+or-0.4 kPa at the location 5 mm upstream and 14.2+or-0.8 kPa at the location 5 mm downstream. The lowest value, 11.6+or-0.8 kPa, was found 1 mm downstream. O/sub 2/ disappearance rates (dPO/sub 2//dt) at each location were also measured after stopping perfusion to the segment. The disappearance rates varied axially, with the fastest rate, -4.1+or-0.6 kPa/min, found 1 mm upstream. At 4 and 5 mm upstream and downstream from the stenosis, the rates were essentially the same, at 2.8+or-0.3 kPa/min. The average value for O/sub 2/ metabolism at the upstream and downstream ends is 5.0*10/sup -4/ mL O/sub 2//mL tissue/min.<<ETX>>","PeriodicalId":165980,"journal":{"name":"Proceedings of the 1988 Fourteenth Annual Northeast Bioengineering Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130000685","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}
The application of spectral analysis methods to radiologically gathered gastric data is discussed. The data is obtained by sampling counts of gamma rays present in the antrum section of the stomach of gastrointestinal patients after each patient was fed two scrambled eggs injected with a radioactive material. The primary goal of this investigation is to provide a noninvasive diagnostic tool to determine the stomach contraction pattern for normals and abnormals. The frequency components of contraction cycle are computed using three methods: (1) Fourier transform, (2) maximum entropy method (MEM), and (3) multiple signal classification (MUSIC). Statistical tests are performed on the frequencies of the normal and abnormal groups, to assess the discrimination powers of these methods. It is shown that Fourier transform performance is not adequate, while MEM and MUSIC produce very good results. The frequency components estimated agree with physiological findings for the normal and abnormal patients.<>
{"title":"Spectrum analysis of gastric emptying","authors":"R. Caponigro, R. Lo, J. Siegel, A. Abutaleb","doi":"10.1109/NEBC.1988.19396","DOIUrl":"https://doi.org/10.1109/NEBC.1988.19396","url":null,"abstract":"The application of spectral analysis methods to radiologically gathered gastric data is discussed. The data is obtained by sampling counts of gamma rays present in the antrum section of the stomach of gastrointestinal patients after each patient was fed two scrambled eggs injected with a radioactive material. The primary goal of this investigation is to provide a noninvasive diagnostic tool to determine the stomach contraction pattern for normals and abnormals. The frequency components of contraction cycle are computed using three methods: (1) Fourier transform, (2) maximum entropy method (MEM), and (3) multiple signal classification (MUSIC). Statistical tests are performed on the frequencies of the normal and abnormal groups, to assess the discrimination powers of these methods. It is shown that Fourier transform performance is not adequate, while MEM and MUSIC produce very good results. The frequency components estimated agree with physiological findings for the normal and abnormal patients.<<ETX>>","PeriodicalId":165980,"journal":{"name":"Proceedings of the 1988 Fourteenth Annual Northeast Bioengineering Conference","volume":"268 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115599147","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}
Recent advances in the development of detection schemes for myocardial ischemia which use frequency-domain parameters as detection statistics open up the possibility of using frequency-domain methods in the inverse problem of electrocardiography. The application of the minimum relative entropy (MRE) reconstruction principle to this problem is considered and its theoretical justification is given. The MRE method is compared to a standard time-domain least-squares method, constrained least squares (CLS). Initial results indicate that the MRE method promises to be able to overcome limitations of the time-domain least-squares methods which tend to make the latter difficult to apply in a clinical setting.<>
{"title":"A frequency domain inverse solution in electrocardiography","authors":"D.H. Brooks, C. Nikias, J. Siegel","doi":"10.1109/NEBC.1988.19376","DOIUrl":"https://doi.org/10.1109/NEBC.1988.19376","url":null,"abstract":"Recent advances in the development of detection schemes for myocardial ischemia which use frequency-domain parameters as detection statistics open up the possibility of using frequency-domain methods in the inverse problem of electrocardiography. The application of the minimum relative entropy (MRE) reconstruction principle to this problem is considered and its theoretical justification is given. The MRE method is compared to a standard time-domain least-squares method, constrained least squares (CLS). Initial results indicate that the MRE method promises to be able to overcome limitations of the time-domain least-squares methods which tend to make the latter difficult to apply in a clinical setting.<<ETX>>","PeriodicalId":165980,"journal":{"name":"Proceedings of the 1988 Fourteenth Annual Northeast Bioengineering Conference","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132604636","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}
Nonlinear interaction in the acoustic brainstem response can be demonstrated by subtracting the response to binaural stimulation from the sum of responses to monaural stimulation. The resulting binaural difference waveform is nonflat during peaks IV and/or V of the acoustic brainstem response. The nonlinearity probably arises at some neural elements which lie in the ascending auditory brainstem and which receive inputs from both ears. The growth of the binaural difference was tested in rats under an increasing-stimulus-level series and the results were compared with the responses of two hypothetical models that can account for the binaural difference generation. The data are in good agreement with one of the models, which assumes that binaural difference is generated from contralateral inhibition under binaural stimulation.<>
{"title":"Non-linear interaction of binaural stimuli","authors":"M. Psaltikidou, R. Gaumond","doi":"10.1109/NEBC.1988.19358","DOIUrl":"https://doi.org/10.1109/NEBC.1988.19358","url":null,"abstract":"Nonlinear interaction in the acoustic brainstem response can be demonstrated by subtracting the response to binaural stimulation from the sum of responses to monaural stimulation. The resulting binaural difference waveform is nonflat during peaks IV and/or V of the acoustic brainstem response. The nonlinearity probably arises at some neural elements which lie in the ascending auditory brainstem and which receive inputs from both ears. The growth of the binaural difference was tested in rats under an increasing-stimulus-level series and the results were compared with the responses of two hypothetical models that can account for the binaural difference generation. The data are in good agreement with one of the models, which assumes that binaural difference is generated from contralateral inhibition under binaural stimulation.<<ETX>>","PeriodicalId":165980,"journal":{"name":"Proceedings of the 1988 Fourteenth Annual Northeast Bioengineering Conference","volume":" 27","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132158707","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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