Francisco Jara-Rojas - Academia.edu (original) (raw)
Papers by Francisco Jara-Rojas
OENO One, 2009
... different soil management strategies. H Valdés-Gómez, Christian Gary, Philippe Cartolaro, M L... more ... different soil management strategies. H Valdés-Gómez, Christian Gary, Philippe Cartolaro, M Lolas-Caneo, Agnès Calonnec in Crop Protection (2011). 1 reader Save reference to library · Related research. SOIL WATER STORAGE ...
VII International Symposium on Olive Growing, 2014
ABSTRACT Stomatal conductance (gs) is a plant variable normally used in models that estimate plan... more ABSTRACT Stomatal conductance (gs) is a plant variable normally used in models that estimate plant water requirements, and furthermore can be used as an integrative tool to monitoring the level of plant water restriction. However, gs requires skills and heavy devices, which drastically limit the number of replications either in space or in time. Moreover, due to the significant spatial variability in olive orchards, extrapolation of one measurement on a whole field or on a whole orchard scale can hardly be done. The aim of this paper is to propose a model that uses only one measurement performed on a reference site in order to predict gs and its spatial variability over the whole field. An experiment to identify and test the model was carried out over a commercial drip-irrigated olive orchard (Olea europaea L. ‘Arbequina’) located in Pencahue valley, Maule Region, Chile (35°23’LS; 71°44’LW; WGS 84; 96 m a.s.l.). Measurements of gs were done in 29 dates using a porometer (PP Systems, PMR-5, Amesbury, Massachusetts, USA) during three growing seasons (2008-09, 2009-10, 2010-11). A regular grid of 30 measurement sites was distributed over the field. Results showed a significant within-field variability of gs over space and time, and the existence of significant linear relations among gs values. Also, the model was able to predict spatial variability of gs with a spatial and temporal mean error of 53.3 and 52.0 mmol m-2 s-1, respectively. Further studies will aim to confirm the relevancy of this approach for different cultivars and locations
2011 IEEE International Symposium on VR Innovation, 2011
Page 1. Real-Time Scalable Recognition and Tracking based on the Server-Client Model for Mobile A... more Page 1. Real-Time Scalable Recognition and Tracking based on the Server-Client Model for Mobile Augmented Reality Jaewon Ha, Kyusung Cho, Francisco A. Rojas, Hyun S. Yang Computer Science Department, Korea Advanced Institute of Science and Technology ...
2014 International Conference on Cyberworlds, 2014
Our paper introduces a novel approach for collision avoidance (CA) among social groups that uses ... more Our paper introduces a novel approach for collision avoidance (CA) among social groups that uses the collective gaze-movement angle (CGMA) between groups as the primary approach for collision prediction. Rules are used for handling the CA steering such that it mimics how real human groups travel together in wide-open walkable areas. We also show how to apply reciprocal velocity obstacle (RVO) based CA to groups as an alternative, and we use this alternative as a baseline for comparison in our approach for group-to-group CA. In an immersive evaluation using a head-mounted display, a group of people determined that our CA approach was much more believable than the RVO based CA approach for groups.
Earth Observing Systems V, 2000
Earth Observing Systems VI, 2002
ABSTRACT
2014 International Conference on Cyberworlds, 2014
Most prior crowd simulations do not have groups of people moving in a social manner. In our work,... more Most prior crowd simulations do not have groups of people moving in a social manner. In our work, we use a two level steering system based on two classes: group agent and pedestrian agent. By interpolating the current and desired slot positions of the group agent according to formation templates, dynamic social group formations can be achieved and can also adapt to the width of passageways by using our proposed ray casting technique. Based on this interpolation approach, we introduce slot-locking which keeps subgroups in a group shoulder-to-shoulder regardless of the current formation state assuming sufficient surrounding space exists. When this happens, hand holding between adjacent members may occur. Individual characteristics such as age and body shape impact the overall group speed. In an immersive evaluation using a head-mounted display (HMD), participants validated the realism of dynamic social group behavior as virtual pedestrians safely navigated via traffic light crosswalks and sidewalks with vehicular traffic encountered on the way.
Remote Sensing of Environment, 2002
A project to characterize the Moderate Resolution-Imaging Spectroradiometer (MODIS) spatial respo... more A project to characterize the Moderate Resolution-Imaging Spectroradiometer (MODIS) spatial response (SR) using preflight Modulation Transfer Function (MTF) validation data and on-orbit imagery is described, and the results from the analyses are presented. The preflight ...
Journal of Pineal Research, 1999
other antioxidants prolong the postmortem activity of the outer hair cells of the organ of Corti:... more other antioxidants prolong the postmortem activity of the outer hair cells of the organ of Corti: Its relation to the type of death. J. Pineal Res. 1999; 27:73-77. 0 Munksgaard, Copenhagen
Journal of Pineal Research, 2000
The mechanism of the ototoxicity caused by cisplatin is based in the generation of reactive oxyge... more The mechanism of the ototoxicity caused by cisplatin is based in the generation of reactive oxygen species, which interferes with the antioxidant protection of the organ of Corti. Conversely, the protection of the cochlea with antioxidants ameliorates the ototoxicity by cisplatin. The ototoxicity produced by cisplatin can be reversible or persistent, depending on the age of the patient, cumulative doses, number of chemotherapy cycles, history of noise exposure, and deteriorating renal function. We have obtained in rats an ototoxic chart utilizing cisplatin (10 mg/kg body weight injected intraperitoneally, once only). Together with this treatment, the animals were treated with melatonin in the drinking water (10 mg/L) or injected subcutaneously (250 mg), and with an antioxidant mixture, injected subcutaneously, composed of 0.25 mg alpha-tocopherol acid succinate, 3 mg ascorbic acid, 1 mg glutathione, and 60 mg N-acetylcysteine. The distortion product otoacoustic emissions were determined for a prolonged period of time for each animal. The ototoxicity produced by cisplatin was maximal from days 7 to 10 post-treatment, returning to normal values in a month. When melatonin and the antioxidant mixture were present, the recovery was between days 10 and 15 post-treatment, independent of the means of administration of the pineal product. We conclude that the ototoxicity caused by cisplatin is ameliorated by melatonin and other antioxidants.
Journal of Oral and Maxillofacial Surgery, 2012
International Urogynecology Journal, 2006
We describe the anatomy of the uterosacral ligament with respect to the sacral plexus. In six adu... more We describe the anatomy of the uterosacral ligament with respect to the sacral plexus. In six adult female embalmed cadavers, we identified the uterosacral ligament and its lateral nerve relations. Using the ischial spine as the starting point and measuring along the axis of the uterosacral ligament, we noted that the S1 trunk of the sacral plexus passes under the ligament 3.9 cm [95% confidence interval (CI), 2.1-5.8 cm] superior to the ischial spine. The S2 trunk passes under the ligament at 2.6 cm (95% CI; 1.5, 3.6 cm), the S3 trunk passes under the ligament at 1.5 cm (95% CI; 0.7, 2.4 cm), and the S4 trunk passes under the ligament at 0.9 cm (95% CI; 0.3, 1.5 cm) superior to the ischial spine. The pudendal nerve forms lateral to the uterosacral ligament. Our data demonstrate that the S1-S4 trunks of the sacral plexus, not the pudendal nerve, are vulnerable to injury during uterosacral ligament suspension.
Computers & Graphics, 2012
Advancements in mobile devices and vision technology have enabled mobile Augmented Reality (AR) t... more Advancements in mobile devices and vision technology have enabled mobile Augmented Reality (AR) to be serviced in real-time using natural features. However, in viewing AR while moving around in the real world, users often encounter new and diverse target objects. Whether the AR system is scalable to the number of target objects is a very crucial issue for mobile AR services in the real world. This scalability, however, has been severely limited because of the small internal storage capacity and memory of the mobile devices. In this paper, a new framework is proposed that achieves scalability for mobile AR. The scalability is achieved with a bag-of-visual-words based recognition module on the server side that is connected to the clients, which are mobile devices, through a conventional Wi-Fi network. On the client side, the coarse-to-fine tracking module enables robust tracking performance with natural features in real-time. In this study, we optimized modules in mobile devices for expediting pose-tracking processing and simultaneously enabled 3D rendering and animation in real-time. We also propose an efficient recognition method in which metadata are provided by the sensors of mobile devices. In the experiment, it takes approximately 0.2 s for the cold start of an AR service initiated on a 10 K object database with a recognition accuracy of 99.87%, which should be acceptable for a variety of real-world mobile AR applications.
Computer Animation and Virtual Worlds, 2013
This paper proposes a collision avoidance behavior model for crowd simulation based on psychologi... more This paper proposes a collision avoidance behavior model for crowd simulation based on psychological findings of human behaviors such as gaze movement angle (GMA), side stepping, gait motion, and personal reaction bubble to have better results in crowd simulation. By calculating the GMA between agents, collision can be predicted and avoided without knowing the exact trajectories of the agents. The proposed model consists of four phases: (1) GMA-based collision prediction for mid/long range by using speed-variant information process space, (2) collision avoidance steering, (3) gait-based locomotion generation, and (4) space keeping based on personal reaction bubble. The effectiveness of the proposed speed-variant information process space was tested on various types of agent flows with different densities. The total loss of kinetic energy accumulated during an agent's movement and the ratio of the length of the path actually traveled to the length of the original path are used as key metrics to figure out the features between the different types of flows. Finally, examples of tuning the parameters with well-known fundamental diagrams are presented. Copyright © 2013 John Wiley & Sons, Ltd.
Chilean journal of agricultural research, 2009
The coupled model of assimilation and stomatal conductance (A-gs) was evaluated to estimate leaf ... more The coupled model of assimilation and stomatal conductance (A-gs) was evaluated to estimate leaf stomatal conductance of a drip-irrigated vineyard (Vitis vinifera L. cv. Cabernet Sauvignon) located in the Pencahue Valley (35º22' S, 71°47' W, 150 m.a.s.l.), Maule Region, Chile, during the 2003-2004 and the 2004-2005 growing seasons.
OENO One, 2009
... different soil management strategies. H Valdés-Gómez, Christian Gary, Philippe Cartolaro, M L... more ... different soil management strategies. H Valdés-Gómez, Christian Gary, Philippe Cartolaro, M Lolas-Caneo, Agnès Calonnec in Crop Protection (2011). 1 reader Save reference to library · Related research. SOIL WATER STORAGE ...
VII International Symposium on Olive Growing, 2014
ABSTRACT Stomatal conductance (gs) is a plant variable normally used in models that estimate plan... more ABSTRACT Stomatal conductance (gs) is a plant variable normally used in models that estimate plant water requirements, and furthermore can be used as an integrative tool to monitoring the level of plant water restriction. However, gs requires skills and heavy devices, which drastically limit the number of replications either in space or in time. Moreover, due to the significant spatial variability in olive orchards, extrapolation of one measurement on a whole field or on a whole orchard scale can hardly be done. The aim of this paper is to propose a model that uses only one measurement performed on a reference site in order to predict gs and its spatial variability over the whole field. An experiment to identify and test the model was carried out over a commercial drip-irrigated olive orchard (Olea europaea L. ‘Arbequina’) located in Pencahue valley, Maule Region, Chile (35°23’LS; 71°44’LW; WGS 84; 96 m a.s.l.). Measurements of gs were done in 29 dates using a porometer (PP Systems, PMR-5, Amesbury, Massachusetts, USA) during three growing seasons (2008-09, 2009-10, 2010-11). A regular grid of 30 measurement sites was distributed over the field. Results showed a significant within-field variability of gs over space and time, and the existence of significant linear relations among gs values. Also, the model was able to predict spatial variability of gs with a spatial and temporal mean error of 53.3 and 52.0 mmol m-2 s-1, respectively. Further studies will aim to confirm the relevancy of this approach for different cultivars and locations
2011 IEEE International Symposium on VR Innovation, 2011
Page 1. Real-Time Scalable Recognition and Tracking based on the Server-Client Model for Mobile A... more Page 1. Real-Time Scalable Recognition and Tracking based on the Server-Client Model for Mobile Augmented Reality Jaewon Ha, Kyusung Cho, Francisco A. Rojas, Hyun S. Yang Computer Science Department, Korea Advanced Institute of Science and Technology ...
2014 International Conference on Cyberworlds, 2014
Our paper introduces a novel approach for collision avoidance (CA) among social groups that uses ... more Our paper introduces a novel approach for collision avoidance (CA) among social groups that uses the collective gaze-movement angle (CGMA) between groups as the primary approach for collision prediction. Rules are used for handling the CA steering such that it mimics how real human groups travel together in wide-open walkable areas. We also show how to apply reciprocal velocity obstacle (RVO) based CA to groups as an alternative, and we use this alternative as a baseline for comparison in our approach for group-to-group CA. In an immersive evaluation using a head-mounted display, a group of people determined that our CA approach was much more believable than the RVO based CA approach for groups.
Earth Observing Systems V, 2000
Earth Observing Systems VI, 2002
ABSTRACT
2014 International Conference on Cyberworlds, 2014
Most prior crowd simulations do not have groups of people moving in a social manner. In our work,... more Most prior crowd simulations do not have groups of people moving in a social manner. In our work, we use a two level steering system based on two classes: group agent and pedestrian agent. By interpolating the current and desired slot positions of the group agent according to formation templates, dynamic social group formations can be achieved and can also adapt to the width of passageways by using our proposed ray casting technique. Based on this interpolation approach, we introduce slot-locking which keeps subgroups in a group shoulder-to-shoulder regardless of the current formation state assuming sufficient surrounding space exists. When this happens, hand holding between adjacent members may occur. Individual characteristics such as age and body shape impact the overall group speed. In an immersive evaluation using a head-mounted display (HMD), participants validated the realism of dynamic social group behavior as virtual pedestrians safely navigated via traffic light crosswalks and sidewalks with vehicular traffic encountered on the way.
Remote Sensing of Environment, 2002
A project to characterize the Moderate Resolution-Imaging Spectroradiometer (MODIS) spatial respo... more A project to characterize the Moderate Resolution-Imaging Spectroradiometer (MODIS) spatial response (SR) using preflight Modulation Transfer Function (MTF) validation data and on-orbit imagery is described, and the results from the analyses are presented. The preflight ...
Journal of Pineal Research, 1999
other antioxidants prolong the postmortem activity of the outer hair cells of the organ of Corti:... more other antioxidants prolong the postmortem activity of the outer hair cells of the organ of Corti: Its relation to the type of death. J. Pineal Res. 1999; 27:73-77. 0 Munksgaard, Copenhagen
Journal of Pineal Research, 2000
The mechanism of the ototoxicity caused by cisplatin is based in the generation of reactive oxyge... more The mechanism of the ototoxicity caused by cisplatin is based in the generation of reactive oxygen species, which interferes with the antioxidant protection of the organ of Corti. Conversely, the protection of the cochlea with antioxidants ameliorates the ototoxicity by cisplatin. The ototoxicity produced by cisplatin can be reversible or persistent, depending on the age of the patient, cumulative doses, number of chemotherapy cycles, history of noise exposure, and deteriorating renal function. We have obtained in rats an ototoxic chart utilizing cisplatin (10 mg/kg body weight injected intraperitoneally, once only). Together with this treatment, the animals were treated with melatonin in the drinking water (10 mg/L) or injected subcutaneously (250 mg), and with an antioxidant mixture, injected subcutaneously, composed of 0.25 mg alpha-tocopherol acid succinate, 3 mg ascorbic acid, 1 mg glutathione, and 60 mg N-acetylcysteine. The distortion product otoacoustic emissions were determined for a prolonged period of time for each animal. The ototoxicity produced by cisplatin was maximal from days 7 to 10 post-treatment, returning to normal values in a month. When melatonin and the antioxidant mixture were present, the recovery was between days 10 and 15 post-treatment, independent of the means of administration of the pineal product. We conclude that the ototoxicity caused by cisplatin is ameliorated by melatonin and other antioxidants.
Journal of Oral and Maxillofacial Surgery, 2012
International Urogynecology Journal, 2006
We describe the anatomy of the uterosacral ligament with respect to the sacral plexus. In six adu... more We describe the anatomy of the uterosacral ligament with respect to the sacral plexus. In six adult female embalmed cadavers, we identified the uterosacral ligament and its lateral nerve relations. Using the ischial spine as the starting point and measuring along the axis of the uterosacral ligament, we noted that the S1 trunk of the sacral plexus passes under the ligament 3.9 cm [95% confidence interval (CI), 2.1-5.8 cm] superior to the ischial spine. The S2 trunk passes under the ligament at 2.6 cm (95% CI; 1.5, 3.6 cm), the S3 trunk passes under the ligament at 1.5 cm (95% CI; 0.7, 2.4 cm), and the S4 trunk passes under the ligament at 0.9 cm (95% CI; 0.3, 1.5 cm) superior to the ischial spine. The pudendal nerve forms lateral to the uterosacral ligament. Our data demonstrate that the S1-S4 trunks of the sacral plexus, not the pudendal nerve, are vulnerable to injury during uterosacral ligament suspension.
Computers & Graphics, 2012
Advancements in mobile devices and vision technology have enabled mobile Augmented Reality (AR) t... more Advancements in mobile devices and vision technology have enabled mobile Augmented Reality (AR) to be serviced in real-time using natural features. However, in viewing AR while moving around in the real world, users often encounter new and diverse target objects. Whether the AR system is scalable to the number of target objects is a very crucial issue for mobile AR services in the real world. This scalability, however, has been severely limited because of the small internal storage capacity and memory of the mobile devices. In this paper, a new framework is proposed that achieves scalability for mobile AR. The scalability is achieved with a bag-of-visual-words based recognition module on the server side that is connected to the clients, which are mobile devices, through a conventional Wi-Fi network. On the client side, the coarse-to-fine tracking module enables robust tracking performance with natural features in real-time. In this study, we optimized modules in mobile devices for expediting pose-tracking processing and simultaneously enabled 3D rendering and animation in real-time. We also propose an efficient recognition method in which metadata are provided by the sensors of mobile devices. In the experiment, it takes approximately 0.2 s for the cold start of an AR service initiated on a 10 K object database with a recognition accuracy of 99.87%, which should be acceptable for a variety of real-world mobile AR applications.
Computer Animation and Virtual Worlds, 2013
This paper proposes a collision avoidance behavior model for crowd simulation based on psychologi... more This paper proposes a collision avoidance behavior model for crowd simulation based on psychological findings of human behaviors such as gaze movement angle (GMA), side stepping, gait motion, and personal reaction bubble to have better results in crowd simulation. By calculating the GMA between agents, collision can be predicted and avoided without knowing the exact trajectories of the agents. The proposed model consists of four phases: (1) GMA-based collision prediction for mid/long range by using speed-variant information process space, (2) collision avoidance steering, (3) gait-based locomotion generation, and (4) space keeping based on personal reaction bubble. The effectiveness of the proposed speed-variant information process space was tested on various types of agent flows with different densities. The total loss of kinetic energy accumulated during an agent's movement and the ratio of the length of the path actually traveled to the length of the original path are used as key metrics to figure out the features between the different types of flows. Finally, examples of tuning the parameters with well-known fundamental diagrams are presented. Copyright © 2013 John Wiley & Sons, Ltd.
Chilean journal of agricultural research, 2009
The coupled model of assimilation and stomatal conductance (A-gs) was evaluated to estimate leaf ... more The coupled model of assimilation and stomatal conductance (A-gs) was evaluated to estimate leaf stomatal conductance of a drip-irrigated vineyard (Vitis vinifera L. cv. Cabernet Sauvignon) located in the Pencahue Valley (35º22' S, 71°47' W, 150 m.a.s.l.), Maule Region, Chile, during the 2003-2004 and the 2004-2005 growing seasons.