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Researchers have developed a new solution to tracking objects hidden behind scattering media by analyzing the fluctuations in optical "noise" created by their movement. In The Optical Society's journal for high impact research, Optica, researchers from the University of Central Florida (CREOL) demonstrate their technique by tracking the location of an object as it is moved within an enclosed box. The approach could help advance real-time remote sensing for military and other applications. For example, it could be used to track vehicles or aircraft traveling through fog. It could also be useful for areas of biomedical research that involve fast-moving particles that cannot be observed directly, according to the researchers. There are many technologies capable of detecting, describing and tracking objects that are far away or that cannot be observed visually. However, most existing technologies, such as Light Detection and Ranging (LIDAR), require a line of sight between the object and the sensor, which means they do not work well when the object is obscured by clouds, fog or other conditions that scatter light. "We are promoting a paradigm shift," said Aristide Dogariu from the University of Central Florida and leader of the research team. "Instead of illuminating the object with a coherent beam of light, we're illuminating it with random light. Looking at how the fluctuations of the light are modified by the interaction with the object allows us to retrieve information about the object." Existing tracking technologies use one of two approaches. Laser-based methods such as LIDAR point a beam of light at the object and then move the beam around to deduce information such as the object's size, shape and trajectory. Imaging-based methods, on the other hand, take a series of images of the object and then perform computations to track its movement over time. "These are very good strategies that have been in place for decades, and under ideal conditions their performance cannot be surpassed," said Dogariu. "But as soon as something in the line of sight scatters and randomizes the light, you run into problems." Dogariu's team has spent more than a decade learning how to infer information from the fluctuations in light; they previously applied these concepts to developing new tools for sensing the properties of materials and for super-resolution microscopy. In their latest research, they sought to track moving objects in conditions where it is not possible to see the object and not possible to control or pinpoint the directionality of the light shining on it. "An object that is hidden behind some scattering diffuser is not illuminated by a spatially coherent beam," said Dogariu. "The movement of the object, the size of the object and the properties of the object affect the statistical properties of the noise-like optical field, and this effect is what we measure." Because light behaves in a predictable way, Dogariu's team was able to develop statistical methods to separate natural noise from fluctuations that are created by the movement of the target object. To test the approach, the researchers enclosed a small object within a plastic box that is designed to scatter light. Shining a beam of coherent light onto one of the scattering walls creates a secondary light source inside the box. The target object scatters this light and then the light waves are further randomized when light passes back through the scattering walls. The light is then collected outside the box by an integrating detector, which uses an algorithm to distinguish natural noise from the fluctuations caused by the object. "If the target that is surrounded by this enclosure starts to move, then the fluctuations that it imposes on the light coming out of the box can be detected from any direction very efficiently," said Dogariu. Although it can detect the hidden object from any location outside the enclosure, the system cannot identify a non-moving object. Some other technologies have recently been developed that allow tracking of obscured objects by repeatedly scanning or imaging them over time. However, those approaches require complex optical instruments and large-scale data processing, which can make them impractical for following fast-moving objects. In their experiments, Dogariu's team was able to accurately track the movement of the object within the scattering enclosure in real time using a simpler and more versatile setup. "The advantage of recovering information based on fluctuations is that it is more robust against external perturbations," said Dogariu. "It is robust against disturbances between the light source and the object and between the object and the receiver." Because the system extracts information about movement in each direction independently, the approach efficiently senses position for all degrees of freedom (left-right, up-down and diagonal). In addition, because the method follows the motion of the target's center of mass, the tracking accuracy is not affected when the object tilts or rotates. The method's main drawback is the limited level of detail it can provide about the target object. While it can detect the speed and direction at which the object moves and may be able to reveal the object's size, it cannot reveal its color, material, or necessarily its shape. "You cannot recover detailed information with this method, but if you simplify the question to what you really need to know, you can solve certain task-oriented problems," said Dogariu. As a next step, the team is working to refine the approach to handle more complex environments, larger scenes and scenes with lower levels of incoming light. Their hope is that these improvements will bring the system closer to real-world applications in biomedicine, remote sensing and other areas. Though the research involved light waves, similar noise-based approaches could be implemented in other domains, such as acoustics or microwaves, Dogariu said.


Researchers have developed a new solution to tracking objects hidden behind scattering media by analyzing the fluctuations in optical "noise" created by their movement. In The Optical Society's journal for high impact research, Optica, researchers from the University of Central Florida (CREOL) demonstrate their technique by tracking the location of an object as it is moved within an enclosed box. The approach could help advance real-time remote sensing for military and other applications. For example, it could be used to track vehicles or aircraft traveling through fog. It could also be useful for areas of biomedical research that involve fast-moving particles that cannot be observed directly, according to the researchers. There are many technologies capable of detecting, describing and tracking objects that are far away or that cannot be observed visually. However, most existing technologies, such as Light Detection and Ranging (LIDAR), require a line of sight between the object and the sensor, which means they do not work well when the object is obscured by clouds, fog or other conditions that scatter light. "We are promoting a paradigm shift," said Aristide Dogariu from the University of Central Florida and leader of the research team. "Instead of illuminating the object with a coherent beam of light, we're illuminating it with random light. Looking at how the fluctuations of the light are modified by the interaction with the object allows us to retrieve information about the object." Existing tracking technologies use one of two approaches. Laser-based methods such as LIDAR point a beam of light at the object and then move the beam around to deduce information such as the object's size, shape and trajectory. Imaging-based methods, on the other hand, take a series of images of the object and then perform computations to track its movement over time. "These are very good strategies that have been in place for decades, and under ideal conditions their performance cannot be surpassed," said Dogariu. "But as soon as something in the line of sight scatters and randomizes the light, you run into problems." Dogariu's team has spent more than a decade learning how to infer information from the fluctuations in light; they previously applied these concepts to developing new tools for sensing the properties of materials and for super-resolution microscopy. In their latest research, they sought to track moving objects in conditions where it is not possible to see the object and not possible to control or pinpoint the directionality of the light shining on it. "An object that is hidden behind some scattering diffuser is not illuminated by a spatially coherent beam," said Dogariu. "The movement of the object, the size of the object and the properties of the object affect the statistical properties of the noise-like optical field, and this effect is what we measure." Because light behaves in a predictable way, Dogariu's team was able to develop statistical methods to separate natural noise from fluctuations that are created by the movement of the target object. To test the approach, the researchers enclosed a small object within a plastic box that is designed to scatter light. Shining a beam of coherent light onto one of the scattering walls creates a secondary light source inside the box. The target object scatters this light and then the light waves are further randomized when light passes back through the scattering walls. The light is then collected outside the box by an integrating detector, which uses an algorithm to distinguish natural noise from the fluctuations caused by the object. "If the target that is surrounded by this enclosure starts to move, then the fluctuations that it imposes on the light coming out of the box can be detected from any direction very efficiently," said Dogariu. Although it can detect the hidden object from any location outside the enclosure, the system cannot identify a non-moving object. Some other technologies have recently been developed that allow tracking of obscured objects by repeatedly scanning or imaging them over time. However, those approaches require complex optical instruments and large-scale data processing, which can make them impractical for following fast-moving objects. In their experiments, Dogariu's team was able to accurately track the movement of the object within the scattering enclosure in real time using a simpler and more versatile setup. "The advantage of recovering information based on fluctuations is that it is more robust against external perturbations," said Dogariu. "It is robust against disturbances between the light source and the object and between the object and the receiver." Because the system extracts information about movement in each direction independently, the approach efficiently senses position for all degrees of freedom (left-right, up-down and diagonal). In addition, because the method follows the motion of the target's center of mass, the tracking accuracy is not affected when the object tilts or rotates. The method's main drawback is the limited level of detail it can provide about the target object. While it can detect the speed and direction at which the object moves and may be able to reveal the object's size, it cannot reveal its color, material, or necessarily its shape. "You cannot recover detailed information with this method, but if you simplify the question to what you really need to know, you can solve certain task-oriented problems," said Dogariu. As a next step, the team is working to refine the approach to handle more complex environments, larger scenes and scenes with lower levels of incoming light. Their hope is that these improvements will bring the system closer to real-world applications in biomedicine, remote sensing and other areas. Though the research involved light waves, similar noise-based approaches could be implemented in other domains, such as acoustics or microwaves, Dogariu said.


Christodoulides D.N.,CREOL
Optics InfoBase Conference Papers | Year: 2016

By harnessing ideas stemming from non-Hermiticity and parity-time (PT) symmetry, novel classes of synthetic structures and devices with counter-intuitive properties can be realized. This could potentially enable new possibilities in the field of optics and integrated photonics. © 2016 OSA.


Li Y.,University of Strasbourg | Fine F.,Technical Institute for Oil Seeds | Fabiano-Tixier A.-S.,University of Strasbourg | Abert-Vian M.,University of Strasbourg | And 3 more authors.
Comptes Rendus Chimie | Year: 2014

This present study was designed to evaluate the performances of five alternative solvents (alcohols: ethanol, isopropanol and terpenes: d-limonene, α-pinene, p-cymene) compared to n-hexane in rapeseed oil extraction. The extracted oils were quantitatively and qualitatively analyzed to compare the solvents' performances in terms of kinetics, fatty acid compositions, lipid yields, and classes. Moreover, micronutrients in extracted oils were also respectively quantified by high-performance liquid chromatography (HPLC) and gas chromatography (GC). In addition, the interactions between alternative solvents and rapeseed oil have been theoretically studied with the Hansen solubility methodology to get a better comprehension of dissolving mechanisms. The results indicated that p-cymene could be the most promising solvent for n-hexane substitution with higher lipid yield and good selectivity, despite the micronutrient contents were relatively low. © 2013 Académie des sciences.


PubMed | University of Avignon, CREOL, SAIPOL and Technical institute for oilseed crops
Type: | Journal: Ultrasonics sonochemistry | Year: 2016

Ultrasound-assisted extraction of rapeseed oil was investigated and compared with conventional extraction for energy efficiency, throughput time, extraction yield, cleanness, processing cost and product quality. A multivariate study enabled us to define optimal parameters (7.7 W/cm(2) for ultrasonic power intensity, 40 C for processing temperature, and a solid/liquid ratio of 1/15) for ultrasound-assisted extraction of oil from oilseeds to maximize lipid yield while reducing solvent consumption and extraction time using response surface methodology (RSM) with a three-variable central composite design (CCD). A significant difference in oil quality was noted under the conditions of the initial ultrasound extraction, which was later avoided using ultrasound in the absence of oxygen. Three concepts of multistage cross-current extraction were investigated and compared: conventional multistage maceration, ultrasound-assisted maceration and a combination, to assess the positive impact of using ultrasound on the seed oil extraction process. The study concludes that ultrasound-assisted extraction of oil is likely to reduce both economic and ecological impacts of the process in the fat and oil industry.


Chapuis A.,Institute International Dingenierie Of Leau Et Of Lenvironnement 2Ie | Chapuis A.,French National Center for Scientific Research | Chapuis A.,CIRAD - Agricultural Research for Development | Blin J.,Institute International Dingenierie Of Leau Et Of Lenvironnement 2Ie | And 3 more authors.
Industrial Crops and Products | Year: 2014

The performance of oil expression from Jatropha curcas L. (Jatropha) seeds using a pilot scale continuous screw press was studied. The influence of seed pre-treatment, i.e. whole, crushed and deshelled seeds, screw-press operational settings (shaft rotational speed and press cake outlet section) was investigated. For each experiment, the material flows (seeds, press cake and crude oil) were measured and analysed for their oil, water and solids contents. The behaviour of oil expression was very sensitive to seeds preparation. It was shown that for whole seeds, a good reproducibility was obtained, whereas for crushed or deshelled seeds, heterogeneity of the feed led to unsteady pressing conditions and important discrepancies in the performance. The presence of seed shells contributes to build a porous solid matrix which favours oil flow through the press cake. For whole seeds, a correlation between oil recovery and seed throughput was proposed. The mass balance consistency was carefully analysed and oil yield was determined using a direct and an indirect method. A good linear correlation between seed and press cake throughputs was observed: the seed throughput is always divided in a stream of crude oil and a stream of press cake in the same proportion. This important result shows that the residual oil in press cake and the amount of solids carried by the oil are directly related and determine the efficacy of the separation. Thus, for a given screw press and feed material, the oil sediment content can be predicted knowing the oil recovery. The energy consumption during pressing was measured and modelled as a function of oil recovery and seeds oil content. The specific mechanical energy for oil expression was less than 5% of the energy content of the oil and a minimum mechanical energy requirement was generally observed at oil recoveries between 70% and 80%. © 2013 Elsevier B.V.


Quinsac A.,Terres Inovia | Carre P.,CREOL | Fine F.,Terres Inovia
European Journal of Lipid Science and Technology | Year: 2016

Cold-pressing has well-known adverse effects on solvent extraction performances from the resulting cakes. Here, we investigated the added value of an additional pelletizing step in a batch extractor (3.5 kg) to produce pellets with better physical quality (durability, wettability, and percolation speed) for hexane extraction and desolventization. We then led a second experiment in a pilot-scale continuous belt extractor (250 kg/h) to evaluate the feasibility of the process and its impacts on mass balance, oil and meal quality, and energy consumption. Results showed that pelletizing cold-pressed cakes enables suitable oil extraction and meal desolventization performances. Meal quality was preserved and press oil quality enhanced due to a very low phosphorus content (<10 ppm). The energy balance of cold-pressing was compared to the regular process using the flaking-cooking-pressing preparation before solvent extraction on the basis of data obtained here or from industrial crushing plants. Results showed that cold-pressing may lead to 69% energy savings in the preparation phase (40 vs. 131 kWh/t) and 32% energy savings at whole-process level (192 vs. 283 kWh/t). The scheme also has benefits in terms of greenhouse gas emissions (36.8 vs. 58.5 kg CO2 t−1). Practical applications: Industrial rapeseed oil extraction currently relies on a two-step process of preparation (conditioning, flaking, cooking, pressing) and solvent extraction (percolation, miscella distillation, meal desolventizing). Cooking and desolventizing are the biggest energy users in the process. Using cold-pressing to remove the cooking step was identified as a simple and effective way to reduce whole-process energy consumption. Our results show that pelletizing cold-pressed cakes not only avoids the adverse effects of cold-pressing on solvent extraction performances but can also lead to significant energy savings and better-quality pressing oil. Cold Pressing used as an alternative to traditional preparation allows substantial energy savings. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim


Carre P.,CREOL
OCL - Oleagineux Corps Gras Lipides | Year: 2012

Energy consumption in oil mills is a major item of costs and a sensitive point in the production of biofuels. To improve their performance, industrials can recover low-temperature heat thanks to a new technology of heat exchangers suitable for treating granular solid materials. Information about the energy requirements of the rapeseed crushing being not readily available, the article gives a detailed assessment of consumption items (per ton of seed: 263 MJ for preparation operations and 284 MJ for solvent extraction). These exchangers used as pre-conditioners saves about 55 MJ.t-1 of heat by use of steam condensates. We could go further in use of these devices on the one hand to recover heat from press cake and meal, and secondly to use recovered energy to dry and warm up the seeds before pre-pressing. In this configuration, the energy savings could reach 38% of current needs.


Sunflower meal is an alternative source of proteins for feedstuff but its high fiber content reduces the nutritional value. Different dehulling processes can improve the protein content and the nutritional value of meal. Partially dehulled sunflower meals with 32% and 36% of proteins produced in different crushing plants in France had been compared to non-dehulled sunflower meal (29% of proteins). The total French feedstuff production was simulated with a model including prices of raw materials observed during 2010-2011 campaign. The interest prices of the different qualities of sunflower meal compared to soybean meal varied from 0.43, 0.50 to 0.70 for 29, 32 and 36% of proteins content respectively. The 36% protein sunflower meal seems very well adapted to laying hens and ducks diets where 29% type should be more adapted to meat cows, sows and rabbits who need less concentrated diets. The new market for the 36 % protein sunflower meal type could notably help to provide local sources of proteins for high quality poultry production.


Carre P.,CREOL | Pouzet A.,CETIOM
OCL - Oilseeds and fats, crops and lipids | Year: 2014

Global rapeseed production has undergone sustained growth over the past 20 years. Having surpassed cottonseed production in the early 2000's, it is now the second most produced oilseed behind soybeans. The major producers are China, India, Canada and European Union (27). During this same period, rapeseed crushing has risen strongly, Europe being the major player in this expansion (development of biodiesel) followed to a lesser extent by Canada and China. World exports of rapeseeds are dominated by Canada, by far the largest exporter. Japan is a traditional importer, while China and the EU (27) are less regular buyers. Although less spectacular than palm oil growth, rapeseed oil growth is also remarkable. Its consumption occurs mainly in the crushing countries, the EU being the principal consumer. Rapeseed meal is the second major oilseed meal produced worldwide (after soybean meal). It has been following broadly the same trends as seeds and oils, this evolution was marked a short period of stagnation in the early 2000's. Consumption of rapeseed meal has grown strongly in the EU (which is deficient in protein feed), in China (due to its extraordinary economic development), and in the USA (due to milk producers' demand for feed). The main exporters of rapeseed meals are Canada and India. Oilseed prices spiked in 2008 and since 2010 are remaining at historically high levels: whilst prices fell sharply following the 2013 harvest, they remain well above the lows of 2009. Rape seed meal, however, will remain a secondary meal with known drawbacks; there is little prospect of its price going higher than 65-70% of that of soybean meal. © P. Carré 2014 A. Pouzet, published by EDP Sciences.

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