G. Glaspell, J. Wilkins, John Anderson, M. S. El-shall
Rare earth doped upconverting nanoparticles have been synthesized via laser vaporization controlled condensation (LVCC) and their photoluminescence properties were characterized using 980 nm laser diode excitation. This procedure is highly tunable, specifically by increasing the Yb3+ to Er3+ concentration the observed green emission decreases and the observed red emission increases. We have also shown that nearly equal peaks of blue, green and red emissions producing a virtually white upconverter could be synthesized by appropriately mixing Tm3+, Ho3+, and Er3+. We have also investigated the upconversion efficiency in a variety of lattices including Y2O3, Gd2O3 and La2O3. TEM confirmed that the as-formed particles were ~ 10 nm in size and XRD indicated that the overall crystal structure was predominately cubic.
{"title":"Formation of rare-earth upconverting nanoparticles using laser vaporization controlled condensation","authors":"G. Glaspell, J. Wilkins, John Anderson, M. S. El-shall","doi":"10.1117/12.778030","DOIUrl":"https://doi.org/10.1117/12.778030","url":null,"abstract":"Rare earth doped upconverting nanoparticles have been synthesized via laser vaporization controlled condensation (LVCC) and their photoluminescence properties were characterized using 980 nm laser diode excitation. This procedure is highly tunable, specifically by increasing the Yb3+ to Er3+ concentration the observed green emission decreases and the observed red emission increases. We have also shown that nearly equal peaks of blue, green and red emissions producing a virtually white upconverter could be synthesized by appropriately mixing Tm3+, Ho3+, and Er3+. We have also investigated the upconversion efficiency in a variety of lattices including Y2O3, Gd2O3 and La2O3. TEM confirmed that the as-formed particles were ~ 10 nm in size and XRD indicated that the overall crystal structure was predominately cubic.","PeriodicalId":133868,"journal":{"name":"SPIE Defense + Commercial Sensing","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121097800","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}
This paper presents a wireless distributed pyroelectric sensor system, whose sensing visibilities are modulated by Frensnel lens arrays and coded masks, for multiple human walker recognition. One goal of our research is to make wireless distributed pyroelectric sensor nodes an alternative to the centralized infrared video sensors, with lower cost, lower detectability, lower power consumption and computation, and less privacy infringement. In our previous study, we succeeded in identifying individuals walking along the same path, or just randomly inside a room, with an identification rate higher than 80$%$ for around 10 subjects, only using one wireless sensor node. To improve the identification rate and the number of subjects that can be recognized, one-by-one or simultaneously, we employ multiple sensor nodes to leverage the performance of the distributed sensor system. The fusion of pyroelectric biometrics from multiple nodes is performed at four different levels: sample, feature, score, and decision. The experimental results show that the proposed pyroelectric sensor system has potential to be a reliable biometric system for the verification/identification of a small group of human objects. Its applications include security monitoring, human-machine interfaces, and virtual environments.
{"title":"Multiple walker recognition using wireless distributed pyro-electric sensors","authors":"Nanxiang Li, Qi Hao","doi":"10.1117/12.777253","DOIUrl":"https://doi.org/10.1117/12.777253","url":null,"abstract":"This paper presents a wireless distributed pyroelectric sensor system, whose sensing visibilities are modulated by Frensnel lens arrays and coded masks, for multiple human walker recognition. One goal of our research is to make wireless distributed pyroelectric sensor nodes an alternative to the centralized infrared video sensors, with lower cost, lower detectability, lower power consumption and computation, and less privacy infringement. In our previous study, we succeeded in identifying individuals walking along the same path, or just randomly inside a room, with an identification rate higher than 80$%$ for around 10 subjects, only using one wireless sensor node. To improve the identification rate and the number of subjects that can be recognized, one-by-one or simultaneously, we employ multiple sensor nodes to leverage the performance of the distributed sensor system. The fusion of pyroelectric biometrics from multiple nodes is performed at four different levels: sample, feature, score, and decision. The experimental results show that the proposed pyroelectric sensor system has potential to be a reliable biometric system for the verification/identification of a small group of human objects. Its applications include security monitoring, human-machine interfaces, and virtual environments.","PeriodicalId":133868,"journal":{"name":"SPIE Defense + Commercial Sensing","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123377973","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}
Chart Venture Partners' (CVP) approach to investing in Chemical, Biological, Radiological, Nuclear, and Explosives (CBRNE) detection technologies can be best understood in the context of the unique partnership between the firm's two founding institutions. CVP was founded as a partnership between the Chart Group, a New York-based merchant banking and venture capital boutique, and InSitech Incorporated, a 501(c)(3) non-profit commercial partnership intermediary for the U.S. Army's Armament Research Development and Engineering Center (ARDEC) at Picatinny Arsenal in New Jersey. The partnership between Chart Group and Insitech has yielded a new investment model. Unlike most venture funds, CVP operates with a singular focus on early-stage defense and security technologies, with the important caveat that everything we invest in must also have dual-use application in large-scale commercial markets. CVP believes that early-stage CBRNE companies require five qualities to be viable investment candidates and successful start-up companies: Great Science, Strong IP Positions, Recognized Scientific Champions, Identified Dual-Use Market Pull, and "Real World" Technical Performance Data. When earlystage CBRNE companies decide to seek venture capital and pursue higher growth dual-use business models, we often find that certain issues arise that are not always fully contemplated at the outset, and that can create gaps between what the start-up companies are offering to investors and what those investors are seeking from their potential portfolio companies. These same issues can have significant positive or negative impact on shareholder value over time, depending on how they are managed. Specifically, startups should consider carefully their strategies related to business development, market positioning, government funding, and investment syndicate formation.
{"title":"Chart Venture Partners' perspective on dual-use CBRNE technologies","authors":"C. S. Van Nice, P. J. Gardner","doi":"10.1117/12.783461","DOIUrl":"https://doi.org/10.1117/12.783461","url":null,"abstract":"Chart Venture Partners' (CVP) approach to investing in Chemical, Biological, Radiological, Nuclear, and Explosives (CBRNE) detection technologies can be best understood in the context of the unique partnership between the firm's two founding institutions. CVP was founded as a partnership between the Chart Group, a New York-based merchant banking and venture capital boutique, and InSitech Incorporated, a 501(c)(3) non-profit commercial partnership intermediary for the U.S. Army's Armament Research Development and Engineering Center (ARDEC) at Picatinny Arsenal in New Jersey. The partnership between Chart Group and Insitech has yielded a new investment model. Unlike most venture funds, CVP operates with a singular focus on early-stage defense and security technologies, with the important caveat that everything we invest in must also have dual-use application in large-scale commercial markets. CVP believes that early-stage CBRNE companies require five qualities to be viable investment candidates and successful start-up companies: Great Science, Strong IP Positions, Recognized Scientific Champions, Identified Dual-Use Market Pull, and \"Real World\" Technical Performance Data. When earlystage CBRNE companies decide to seek venture capital and pursue higher growth dual-use business models, we often find that certain issues arise that are not always fully contemplated at the outset, and that can create gaps between what the start-up companies are offering to investors and what those investors are seeking from their potential portfolio companies. These same issues can have significant positive or negative impact on shareholder value over time, depending on how they are managed. Specifically, startups should consider carefully their strategies related to business development, market positioning, government funding, and investment syndicate formation.","PeriodicalId":133868,"journal":{"name":"SPIE Defense + Commercial Sensing","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124777765","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}
A key to mastering asymmetric warfare is the acquisition of accurate intelligence on adversaries and their assets in urban and open battlefields. To achieve this, one needs adequate numbers of tactical sensors placed in locations to optimize coverage, where optimality is realized by covering a given area of interest with the least number of sensors, or covering the largest possible subsection of an area of interest with a fixed set of sensors. Unfortunately, neither problem admits a polynomial time algorithm as a solution, and therefore, the placement of such sensors must utilize intelligent heuristics instead. In this paper, we present a scheme implemented on parallel SIMD processing architectures to yield significantly faster results, and that is highly scalable with respect to dynamic changes in the area of interest. Furthermore, the solution to the first problem immediately translates to serve as a solution to the latter if and when any sensors are rendered inoperable.
{"title":"A heuristic for deriving the optimal number and placement of reconnaissance sensors","authors":"S. Nanda, J. Weeks, M. Archer","doi":"10.1117/12.780282","DOIUrl":"https://doi.org/10.1117/12.780282","url":null,"abstract":"A key to mastering asymmetric warfare is the acquisition of accurate intelligence on adversaries and their assets in urban and open battlefields. To achieve this, one needs adequate numbers of tactical sensors placed in locations to optimize coverage, where optimality is realized by covering a given area of interest with the least number of sensors, or covering the largest possible subsection of an area of interest with a fixed set of sensors. Unfortunately, neither problem admits a polynomial time algorithm as a solution, and therefore, the placement of such sensors must utilize intelligent heuristics instead. In this paper, we present a scheme implemented on parallel SIMD processing architectures to yield significantly faster results, and that is highly scalable with respect to dynamic changes in the area of interest. Furthermore, the solution to the first problem immediately translates to serve as a solution to the latter if and when any sensors are rendered inoperable.","PeriodicalId":133868,"journal":{"name":"SPIE Defense + Commercial Sensing","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124546728","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}
J. Vaillancourt, Xuejun Lu, Xuliang Han, D. Janzen, W. Shih
A high-speed flexible transistor made with an ultrapure carbon nanotube (CNT) solution is reported. The carrier transport layer of the CNT-based flexible transistor is formed at room temperature by dispensing a tiny droplet of an electronics-grade CNT solution. Ultra high field-effect mobility of ~ 48,000 cm2/(V×s) has been demonstrated on a thin-film field effect transistor (TFT). A simple trans-impedance voltage follower circuit was made using the CNT-TFT on a transparency film. The circuit exhibited a high modulation speed of 312 MHz and a large current-carrying capacity beyond 20 mA. The transparency and the sheet resistance of the CNT-film were also characterized at different wavelengths. The ink-jet printing-compatible process would enable mass production of large-area electronic circuits on virtually any desired flexible substrate at low cost and high throughput.
{"title":"High-speed transparent flexible electronics","authors":"J. Vaillancourt, Xuejun Lu, Xuliang Han, D. Janzen, W. Shih","doi":"10.1117/12.777348","DOIUrl":"https://doi.org/10.1117/12.777348","url":null,"abstract":"A high-speed flexible transistor made with an ultrapure carbon nanotube (CNT) solution is reported. The carrier transport layer of the CNT-based flexible transistor is formed at room temperature by dispensing a tiny droplet of an electronics-grade CNT solution. Ultra high field-effect mobility of ~ 48,000 cm2/(V×s) has been demonstrated on a thin-film field effect transistor (TFT). A simple trans-impedance voltage follower circuit was made using the CNT-TFT on a transparency film. The circuit exhibited a high modulation speed of 312 MHz and a large current-carrying capacity beyond 20 mA. The transparency and the sheet resistance of the CNT-film were also characterized at different wavelengths. The ink-jet printing-compatible process would enable mass production of large-area electronic circuits on virtually any desired flexible substrate at low cost and high throughput.","PeriodicalId":133868,"journal":{"name":"SPIE Defense + Commercial Sensing","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127890418","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}
Steven P. Williams, Iii a J. Arthur, K. Shelton, Iii Lawrence J. Prinzel, Dr. R. Michael
The Crew Vehicle Interface (CVI) group of the Integrated Intelligent Flight Deck Technologies (IIFDT) has done extensive research in the area of Synthetic Vision (SV), and has shown that SV technology can substantially enhance flight crew situation awareness, reduce pilot workload, promote flight path control precision and improve aviation safety. SV technology is being extended to evaluate its utility for lunar and planetary exploration vehicles. SV may hold significant potential for many lunar and planetary missions since the SV presentation provides a computer-generated view of the terrain and other significant environment characteristics independent of the outside visibility conditions, window locations, or vehicle attributes. SV allows unconstrained control of the computer-generated scene lighting, terrain coloring, and virtual camera angles which may provide invaluable visual cues to pilots/astronauts and in addition, important vehicle state information may be conformally displayed on the view such as forward and down velocities, altitude, and fuel remaining to enhance trajectory control and vehicle system status. This paper discusses preliminary SV concepts for tactical and strategic displays for a lunar landing vehicle. The technical challenges and potential solutions to SV applications for the lunar landing mission are explored, including the requirements for high resolution terrain lunar maps and an accurate position and orientation of the vehicle that is essential in providing lunar Synthetic Vision System (SVS) cockpit displays. The paper also discusses the technical challenge of creating an accurate synthetic terrain portrayal using an ellipsoid lunar digital elevation model which eliminates projection errors and can be efficiently rendered in real-time.
{"title":"Synthetic vision for lunar and planetary landing vehicles","authors":"Steven P. Williams, Iii a J. Arthur, K. Shelton, Iii Lawrence J. Prinzel, Dr. R. Michael","doi":"10.1117/12.777079","DOIUrl":"https://doi.org/10.1117/12.777079","url":null,"abstract":"The Crew Vehicle Interface (CVI) group of the Integrated Intelligent Flight Deck Technologies (IIFDT) has done extensive research in the area of Synthetic Vision (SV), and has shown that SV technology can substantially enhance flight crew situation awareness, reduce pilot workload, promote flight path control precision and improve aviation safety. SV technology is being extended to evaluate its utility for lunar and planetary exploration vehicles. SV may hold significant potential for many lunar and planetary missions since the SV presentation provides a computer-generated view of the terrain and other significant environment characteristics independent of the outside visibility conditions, window locations, or vehicle attributes. SV allows unconstrained control of the computer-generated scene lighting, terrain coloring, and virtual camera angles which may provide invaluable visual cues to pilots/astronauts and in addition, important vehicle state information may be conformally displayed on the view such as forward and down velocities, altitude, and fuel remaining to enhance trajectory control and vehicle system status. This paper discusses preliminary SV concepts for tactical and strategic displays for a lunar landing vehicle. The technical challenges and potential solutions to SV applications for the lunar landing mission are explored, including the requirements for high resolution terrain lunar maps and an accurate position and orientation of the vehicle that is essential in providing lunar Synthetic Vision System (SVS) cockpit displays. The paper also discusses the technical challenge of creating an accurate synthetic terrain portrayal using an ellipsoid lunar digital elevation model which eliminates projection errors and can be efficiently rendered in real-time.","PeriodicalId":133868,"journal":{"name":"SPIE Defense + Commercial Sensing","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124532692","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}
Hyperspectral imagery (HSI) data has proven useful for discriminating targets, however the relatively slow speed at which HSI data is gathered for an entire frame reduces the usefulness of fusing this information with grayscale video. A new sensor under development has the ability to provide HSI data for a limited number of pixels while providing grayscale video for the remainder of the pixels. The HSI data is co-registered with the grayscale video and is available for each frame. This paper explores the exploitation of this new sensor for target tracking. The primary challenge of exploiting this new sensor is to determine where the gathering of HSI data will be the most useful. We wish to optimize the selection of pixels for which we will gather HSI data. We refer to this as spatial sampling. It is proposed that spatial sampling be solved using a utility function where pixels receive a value based on their nearness to a target of interest (TOI). The TOIs are determined from the tracking algorithm providing a close coupling of the tracking and the sensor control. The relative importance or weighting of the different types of TOI will be accomplished by a genetic algorithm. Tracking performance of the spatially sampled tracker is compared to both tracking with no HSI data and although physically unrealizable, tracking with complete HSI data to demonstrate its effectiveness within the upper and lower bounds.
{"title":"A genetic algorithm approach to optimal spatial sampling of hyperspectral data for target tracking","authors":"Barry R. Secrest, J. Vasquez","doi":"10.1117/12.783188","DOIUrl":"https://doi.org/10.1117/12.783188","url":null,"abstract":"Hyperspectral imagery (HSI) data has proven useful for discriminating targets, however the relatively slow speed at which HSI data is gathered for an entire frame reduces the usefulness of fusing this information with grayscale video. A new sensor under development has the ability to provide HSI data for a limited number of pixels while providing grayscale video for the remainder of the pixels. The HSI data is co-registered with the grayscale video and is available for each frame. This paper explores the exploitation of this new sensor for target tracking. The primary challenge of exploiting this new sensor is to determine where the gathering of HSI data will be the most useful. We wish to optimize the selection of pixels for which we will gather HSI data. We refer to this as spatial sampling. It is proposed that spatial sampling be solved using a utility function where pixels receive a value based on their nearness to a target of interest (TOI). The TOIs are determined from the tracking algorithm providing a close coupling of the tracking and the sensor control. The relative importance or weighting of the different types of TOI will be accomplished by a genetic algorithm. Tracking performance of the spatially sampled tracker is compared to both tracking with no HSI data and although physically unrealizable, tracking with complete HSI data to demonstrate its effectiveness within the upper and lower bounds.","PeriodicalId":133868,"journal":{"name":"SPIE Defense + Commercial Sensing","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115568545","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}
Verification of the low measurement uncertainty of a group of eight newly developed pyroelectric detectors at the output of a traditional monochromator is described. The frequency compensated hybrid detector-amplifier packages have fixed 1010 Ω feedback resistors. The characterizations verified that the 3 dB upper roll-off frequencies of the signal-gain curves are close to 100 Hz and the temperature coefficient of responsivity is 0.14 %/oC. The hybrid packages were tested for noise performance in the f/8 beam of a grating monochromator between 900 nm and 2.7 μm. The monochromator output beam-power, the output signal, and the output noise of the hybrid packages were measured and compared. The NEPs were between 3.3 nW/Hz1/2 and 10 nW/Hz1/2. The relative standard uncertainty of the noise measurements was 20 % (k=1). The noise tests were utilized to select hybrid packages with NEPs that are one order of magnitude lower than that of traditional pyroelectric detectors and current-amplifiers. The power responsivity of one hybrid was calibrated against an absolute cryogenic radiometer. With this detector, the measured signal-to-noise ratios were higher than 400 between 1.1 μm and 2.1 μm and 250 at 2.5 μm using a lock-in integrating time-constant of 1 s. The noise test results show that using a hybrid detector with an NEP equal to the group average of about 6 nW/Hz1/2, spectral responsivity measurements with a relative standard uncertainty of 0.2 % to 0.4 % (k=1) can be achieved.
{"title":"Low NEP pyroelectric radiometer standards","authors":"G. Eppeldauer, J. Zeng, H. Yoon","doi":"10.1117/12.776940","DOIUrl":"https://doi.org/10.1117/12.776940","url":null,"abstract":"Verification of the low measurement uncertainty of a group of eight newly developed pyroelectric detectors at the output of a traditional monochromator is described. The frequency compensated hybrid detector-amplifier packages have fixed 1010 Ω feedback resistors. The characterizations verified that the 3 dB upper roll-off frequencies of the signal-gain curves are close to 100 Hz and the temperature coefficient of responsivity is 0.14 %/oC. The hybrid packages were tested for noise performance in the f/8 beam of a grating monochromator between 900 nm and 2.7 μm. The monochromator output beam-power, the output signal, and the output noise of the hybrid packages were measured and compared. The NEPs were between 3.3 nW/Hz1/2 and 10 nW/Hz1/2. The relative standard uncertainty of the noise measurements was 20 % (k=1). The noise tests were utilized to select hybrid packages with NEPs that are one order of magnitude lower than that of traditional pyroelectric detectors and current-amplifiers. The power responsivity of one hybrid was calibrated against an absolute cryogenic radiometer. With this detector, the measured signal-to-noise ratios were higher than 400 between 1.1 μm and 2.1 μm and 250 at 2.5 μm using a lock-in integrating time-constant of 1 s. The noise test results show that using a hybrid detector with an NEP equal to the group average of about 6 nW/Hz1/2, spectral responsivity measurements with a relative standard uncertainty of 0.2 % to 0.4 % (k=1) can be achieved.","PeriodicalId":133868,"journal":{"name":"SPIE Defense + Commercial Sensing","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114774713","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}
We can be inspired by biological systems, but that does not mean we should attempt to directly implement the components from which those biological systems are built. Particularly with cognitive systems, the properties of the components are submerged by a higher level organization which is not deducible from the components. It may be easier to use a process of reverse engineering of the product of a biological system to understand its operation, than theorizing about its operation or attempting to build up the working system from its perceived components. The reverse engineering of a cognitive system to handle a high level task is described, including the extensions required to an already undirected structure. It is shown how construction of operators built on demand at a ground state can be used to make up for the lack of the massively parallel activity of a biological cognitive system.
{"title":"Bio-inspiration not bio-imitation","authors":"Jim Brander","doi":"10.1117/12.771762","DOIUrl":"https://doi.org/10.1117/12.771762","url":null,"abstract":"We can be inspired by biological systems, but that does not mean we should attempt to directly implement the components from which those biological systems are built. Particularly with cognitive systems, the properties of the components are submerged by a higher level organization which is not deducible from the components. It may be easier to use a process of reverse engineering of the product of a biological system to understand its operation, than theorizing about its operation or attempting to build up the working system from its perceived components. The reverse engineering of a cognitive system to handle a high level task is described, including the extensions required to an already undirected structure. It is shown how construction of operators built on demand at a ground state can be used to make up for the lack of the massively parallel activity of a biological cognitive system.","PeriodicalId":133868,"journal":{"name":"SPIE Defense + Commercial Sensing","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130407610","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}
Metallic nanoparticles usually exhibit localized surface plasmon resonance (LSPR) due to the collective oscillation of electrons upon light excitation. Different applications require specific LSPR wavelengths and absorbance spectra. The ability to engineer the nanostructure and to tune the location of the LSPR wavelength is very important for the sensing applications. We present a simple but versatile fabrication technique, the oblique angle deposition, to tune the LSPR wavelength of Ag thin films. Oblique angle deposition was used to produce silver nanoparticle films with nominal thickness from 5 nm to 100nm and two deposition angles, 0° and 85°. With increasing thickness, the LSPR wavelength is blue shifted. At the large deposition angle, the LSPR wavelength is blue shifted by 3nm on average with every 5nm thickness increment. The stability of the Ag LSPR substrate under liquid environment has been studied, and a surface passivation method is proposed. Those substrates are capable of detection 10-10 M NeutrAvidin.
{"title":"Fine tune localized surface plasmon resonance for chemical and biological sensors","authors":"J.-X. Fu, Y. Zhao","doi":"10.1117/12.776909","DOIUrl":"https://doi.org/10.1117/12.776909","url":null,"abstract":"Metallic nanoparticles usually exhibit localized surface plasmon resonance (LSPR) due to the collective oscillation of electrons upon light excitation. Different applications require specific LSPR wavelengths and absorbance spectra. The ability to engineer the nanostructure and to tune the location of the LSPR wavelength is very important for the sensing applications. We present a simple but versatile fabrication technique, the oblique angle deposition, to tune the LSPR wavelength of Ag thin films. Oblique angle deposition was used to produce silver nanoparticle films with nominal thickness from 5 nm to 100nm and two deposition angles, 0° and 85°. With increasing thickness, the LSPR wavelength is blue shifted. At the large deposition angle, the LSPR wavelength is blue shifted by 3nm on average with every 5nm thickness increment. The stability of the Ag LSPR substrate under liquid environment has been studied, and a surface passivation method is proposed. Those substrates are capable of detection 10-10 M NeutrAvidin.","PeriodicalId":133868,"journal":{"name":"SPIE Defense + Commercial Sensing","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2008-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117286419","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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