In this paper, we propose a new metric which measures the distance between two finite sets of tra... more In this paper, we propose a new metric which measures the distance between two finite sets of tracks (a track is a path of either a real or estimated target). This metric is based on the same principle as the Optimal Subpattern Assignment (OSPA) metric devised by Schuhmacher et al. Importantly however, the new metric measures the distance between two finite sets of tracks whereas the OSPA metric measures the distance between two finite sets of target states. By also considering the properties of false tracks, missed tracks and many tracks assigned to one track situations caused by missed detections and false alarms, the minimization of all distances between tracks across two finite sets of tracks employed by the new OSPAMT metric enables performance evaluation of multi-target tracking (MTT) algorithms in a more comprehensive and accurate manner than existing metrics such as the OSPA metric and the enhanced OSPAT metric introduced by Ristic et al which measures the distance between two finite sets of labeled target states.
In the context of energy transition, major oil and gas companies (such as Total, BP, Equinor, She... more In the context of energy transition, major oil and gas companies (such as Total, BP, Equinor, Shell, Eni, Petronas, and Osted, etc.) have diversified their investment portfolios with new energy projects, including those in offshore wind power. Resolution No. 55-NQ/TW dated 11 February 2020 of the Politburo on the orientation of Vietnam's national energy development strategy to 2030, vision to 2045 sets the target: the proportion of renewables in the total primary energy supply will reach about 15-20% by 2030; and 25 - 30% by 2045. For wind power, priority should be given to development in accordance with the ability to ensure system safety with reasonable electricity prices; and formulation of supporting policies and breakthrough mechanisms for offshore wind power development in association with the implementation of the Vietnam Maritime Strategy. The paper focuses on assessing the potential market size for wind power services to 2030 and evaluating the possibility of diversifi...
Intelligent Information and Database Systems, 2018
In this paper, we propose using dynamic ensemble selection (DES) method on ensemble generated bas... more In this paper, we propose using dynamic ensemble selection (DES) method on ensemble generated based on random projection. We first construct the homogeneous ensemble in which a set of base classifier is obtained by a learning algorithm on different training schemes generated by projecting the original training set to lower dimensional down spaces. We then develop a DES method on those base classifiers so that a subset of base classifiers is selected to predict label for each test sample. Here competence of a classifier is evaluated based on its prediction results on the test sample’s \( k - \) nearest neighbors obtaining from the projected data of validation set. Our proposed method, therefore, gains the benefits not only from the random projection in dimensionality reduction and diverse training schemes generation but also from DES method in choosing an appropriate subset of base classifiers for each test sample. The experiments conducted on some datasets selected from four different sources indicate that our framework is better than many state-of-the-art DES methods concerning to classification accuracy.
Using a customer-supplier matched sample of US-listed firms from 1980 to 2016, we study the corpo... more Using a customer-supplier matched sample of US-listed firms from 1980 to 2016, we study the corporate cash-holding relationship between suppliers and their major customers. The key findings suggest that the cash-holding levels of suppliers are positively affected by those of their major customers, consistent with the liquidity argument. The effects are more pronounced when the major customers are in more favourable financial conditions and when they are considered more important to their suppliers. Our results are robust to various endogeneity problems and additional tests. Taken together, these results bring forth an important corporate cash-holding link within the supply chain.
Proceedings of the National Academy of Sciences of the United States of America, Jan 26, 2017
The wMel strain of Wolbachia can reduce the permissiveness of Aedes aegypti mosquitoes to dissemi... more The wMel strain of Wolbachia can reduce the permissiveness of Aedes aegypti mosquitoes to disseminated arboviral infections. Here, we report that wMel-infected Ae. aegypti (Ho Chi Minh City background), when directly blood-fed on 141 viremic dengue patients, have lower dengue virus (DENV) transmission potential and have a longer extrinsic incubation period than their wild-type counterparts. The wMel-infected mosquitoes that are field-reared have even greater relative resistance to DENV infection when fed on patient-derived viremic blood meals. This is explained by an increased susceptibility of field-reared wild-type mosquitoes to infection than laboratory-reared counterparts. Collectively, these field- and clinically relevant findings support the continued careful field-testing of wMel introgression for the biocontrol of Ae. aegypti-born arboviruses.
This paper proposes a new metric based on the Optimal Subpattern Assignment (OSPA) metric for eva... more This paper proposes a new metric based on the Optimal Subpattern Assignment (OSPA) metric for evaluating the performance of multiple target tracking algorithms. It is shown in this paper that by considering the properties of false tracks, missing tracks and miss-detections, the minimization of all distances between tracks enables performance evaluation of multi-target algorithms in a more comprehensive manner than is possible with the OSPA metric for track (OSPAT) introduced by Ristic et al. Keywords: Optimal Subpattern Assignment (OSPA), OSPA metric for track (OSPAT metric), OSPA metric for multiple tracks (OSPAMT), Multi-target Tracking (MTT).
We propose a new multi-target tracking (MTT) algorithm capable of tracking an unknown number of t... more We propose a new multi-target tracking (MTT) algorithm capable of tracking an unknown number of targets that move close and/or cross each other in a dense environment. The optimal Bayes MTT problem is formulated in the Random Finite Set framework and Particle Markov Chain Monte Carlo (PMCMC) is applied to compute the multi-target posterior distribution. The PMCMC technique is a combination of Markov chain Monte Carlo (MCMC) and sequential Monte Carlo methods to design an efficient high dimensional proposal distributions for MCMC algorithms. This technique allows our multi-target tracker to handle high track densities in a computationally feasible manner. Our simulations show that under scenarios with a large number of closely spaced tracks the estimated number of tracks and their trajectories are reliable.
The efficient dispersion of powders in liquids is required in many fields. For this reason, it is... more The efficient dispersion of powders in liquids is required in many fields. For this reason, it is useful to understand the mechanisms of dispersion and the physical properties of powders which influence the dispersion rate. Here, we have chosen to work with a low fat cocoa powder commonly used in the food industry. Firstly, we have determined the physical properties of the powder (densities, cohesion, flowability, size and surface energy) and then measured the dispersion times of cocoa in water using a novel optical method. Further experiments, using the same technique, are performed using larger grains obtained by granulating cocoa powder. It is found that the dispersion times are shorter for the granules and much shorter than the dispersion time for ungranulated powder. The dispersion times for granules increase with the size of granules
This paper presents the MediaGrid project whose goal is the definition of a mediation framework f... more This paper presents the MediaGrid project whose goal is the definition of a mediation framework for transparent access to largely distributed sources. Frameworks are reusable pieces of design being expressed as a set of interfaces and components together with the description of their collaboration. Research topics addressed by the MediaGrid project include meta-data design, generation of mediation queries and adaptive and interactive query evaluation.
We propose a Bayesian multi-target batch processing algorithm capable of tracking an unknown numb... more We propose a Bayesian multi-target batch processing algorithm capable of tracking an unknown number of targets that move close and/or cross each other in a dense clutter environment. The optimal Bayes multi-target tracking problem is formulated in the random finite set framework and a Particle Marginal Metropolis-Hastings (PMMH) technique which is a combination of Metropolis-Hastings (MH) algorithm and sequential Monte Carlo methods is applied to compute the multitarget posterior distribution. The PMMH technique is used to design a high dimensional proposal distributions for the MH algorithm and allows the proposed batch process multi-target tracker to handle a large number of tracks in a computationally feasible manner. Our simulations show that the proposed tracker reliably estimates the number of tracks and their trajectories in scenarios with a large number of closely spaced tracks in a dense clutter environment albeit, more expensive than on-line methods.
Proceedings of the 2008 international symposium on Database engineering & applications - IDEAS '08, 2008
... query brokers Christophe Bobineau Grenoble Informatics Laboratory Grenoble Institute of Techn... more ... query brokers Christophe Bobineau Grenoble Informatics Laboratory Grenoble Institute of Technology Grenoble, France [email protected] Christine Collet Grenoble Informatics Laboratory Grenoble Institute of Technology Grenoble, France [email protected] ...
QBF: A Query Broker Framework for Adaptable Query Evaluation* Christine Collet and Tuyet-Trinh Vu... more QBF: A Query Broker Framework for Adaptable Query Evaluation* Christine Collet and Tuyet-Trinh Vu LSR-IMAG Laboratory, INP Grenoble BP 72, 38402 Saint-Martin d'Heres, France {Christine. Collet, Tuyet-Triah. Vujfflimag. fr Abstract. We present QBF (Query Broker ...
Proceedings. International Database Engineering and Applications Symposium, 2004. IDEAS '04.
This paper shows how to provide adaptable query eval-uation using QBF, a Query Broker Framework t... more This paper shows how to provide adaptable query eval-uation using QBF, a Query Broker Framework that pro-vides a set of tools facilitating the design and implemen-tation of query function in data-intensive distributed appli-cations. The framework allows the use of multiple mech- ...
T he efficient dispersion of powders in liquids is required in many fields. However, there are on... more T he efficient dispersion of powders in liquids is required in many fields. However, there are only a few studies on the physicochemical properties of the powders and the dispersion rate. The process of dispersing an agglomerated powder is mainly controlled by the forces acting between the primary particles, and between particles and liquid. In this paper, we present an experimental study of the dispersion kinetics of a hydrophobic powder (cocoa) in water. We firstly determined the surface free energy of the powder using several methods (static wettability, dynamic wettability). Interpretation of calculated values of spreading coefficients and interaction parameters revealed no energetically favoured cocoa-water interactions. A series of dispersion experiments were conducted in a stirred vessel to investigate the influence of stirring speed, temperature and concentration of powder in water. The dispersion concentration was measured using an optical scattering method, which was shown to give good information for evaluating the dispersion process. The experimental data fit an exponential mathematical model with two parameters (A, a): X(t) ¼ A[1 2 exp(2at)]. It was found that the rate of dispersion depends on the agitation speed with a critical speed 630 rpm. All results are discussed as a function of the agitation speed and temperature.
Proc. of the Conference RIVF, Hanoi, Vietnam, 2003
Abstract This paper presents our work on supporting flexi-ble query evaluation over large distri... more Abstract This paper presents our work on supporting flexi-ble query evaluation over large distributed, heterogeneous, and autonomous sources. Flexibility means that the query evalua-tion process can be configured according to application context-specific, ...
In this paper, we propose a new metric which measures the distance between two finite sets of tra... more In this paper, we propose a new metric which measures the distance between two finite sets of tracks (a track is a path of either a real or estimated target). This metric is based on the same principle as the Optimal Subpattern Assignment (OSPA) metric devised by Schuhmacher et al. Importantly however, the new metric measures the distance between two finite sets of tracks whereas the OSPA metric measures the distance between two finite sets of target states. By also considering the properties of false tracks, missed tracks and many tracks assigned to one track situations caused by missed detections and false alarms, the minimization of all distances between tracks across two finite sets of tracks employed by the new OSPAMT metric enables performance evaluation of multi-target tracking (MTT) algorithms in a more comprehensive and accurate manner than existing metrics such as the OSPA metric and the enhanced OSPAT metric introduced by Ristic et al which measures the distance between two finite sets of labeled target states.
In the context of energy transition, major oil and gas companies (such as Total, BP, Equinor, She... more In the context of energy transition, major oil and gas companies (such as Total, BP, Equinor, Shell, Eni, Petronas, and Osted, etc.) have diversified their investment portfolios with new energy projects, including those in offshore wind power. Resolution No. 55-NQ/TW dated 11 February 2020 of the Politburo on the orientation of Vietnam's national energy development strategy to 2030, vision to 2045 sets the target: the proportion of renewables in the total primary energy supply will reach about 15-20% by 2030; and 25 - 30% by 2045. For wind power, priority should be given to development in accordance with the ability to ensure system safety with reasonable electricity prices; and formulation of supporting policies and breakthrough mechanisms for offshore wind power development in association with the implementation of the Vietnam Maritime Strategy. The paper focuses on assessing the potential market size for wind power services to 2030 and evaluating the possibility of diversifi...
Intelligent Information and Database Systems, 2018
In this paper, we propose using dynamic ensemble selection (DES) method on ensemble generated bas... more In this paper, we propose using dynamic ensemble selection (DES) method on ensemble generated based on random projection. We first construct the homogeneous ensemble in which a set of base classifier is obtained by a learning algorithm on different training schemes generated by projecting the original training set to lower dimensional down spaces. We then develop a DES method on those base classifiers so that a subset of base classifiers is selected to predict label for each test sample. Here competence of a classifier is evaluated based on its prediction results on the test sample’s \( k - \) nearest neighbors obtaining from the projected data of validation set. Our proposed method, therefore, gains the benefits not only from the random projection in dimensionality reduction and diverse training schemes generation but also from DES method in choosing an appropriate subset of base classifiers for each test sample. The experiments conducted on some datasets selected from four different sources indicate that our framework is better than many state-of-the-art DES methods concerning to classification accuracy.
Using a customer-supplier matched sample of US-listed firms from 1980 to 2016, we study the corpo... more Using a customer-supplier matched sample of US-listed firms from 1980 to 2016, we study the corporate cash-holding relationship between suppliers and their major customers. The key findings suggest that the cash-holding levels of suppliers are positively affected by those of their major customers, consistent with the liquidity argument. The effects are more pronounced when the major customers are in more favourable financial conditions and when they are considered more important to their suppliers. Our results are robust to various endogeneity problems and additional tests. Taken together, these results bring forth an important corporate cash-holding link within the supply chain.
Proceedings of the National Academy of Sciences of the United States of America, Jan 26, 2017
The wMel strain of Wolbachia can reduce the permissiveness of Aedes aegypti mosquitoes to dissemi... more The wMel strain of Wolbachia can reduce the permissiveness of Aedes aegypti mosquitoes to disseminated arboviral infections. Here, we report that wMel-infected Ae. aegypti (Ho Chi Minh City background), when directly blood-fed on 141 viremic dengue patients, have lower dengue virus (DENV) transmission potential and have a longer extrinsic incubation period than their wild-type counterparts. The wMel-infected mosquitoes that are field-reared have even greater relative resistance to DENV infection when fed on patient-derived viremic blood meals. This is explained by an increased susceptibility of field-reared wild-type mosquitoes to infection than laboratory-reared counterparts. Collectively, these field- and clinically relevant findings support the continued careful field-testing of wMel introgression for the biocontrol of Ae. aegypti-born arboviruses.
This paper proposes a new metric based on the Optimal Subpattern Assignment (OSPA) metric for eva... more This paper proposes a new metric based on the Optimal Subpattern Assignment (OSPA) metric for evaluating the performance of multiple target tracking algorithms. It is shown in this paper that by considering the properties of false tracks, missing tracks and miss-detections, the minimization of all distances between tracks enables performance evaluation of multi-target algorithms in a more comprehensive manner than is possible with the OSPA metric for track (OSPAT) introduced by Ristic et al. Keywords: Optimal Subpattern Assignment (OSPA), OSPA metric for track (OSPAT metric), OSPA metric for multiple tracks (OSPAMT), Multi-target Tracking (MTT).
We propose a new multi-target tracking (MTT) algorithm capable of tracking an unknown number of t... more We propose a new multi-target tracking (MTT) algorithm capable of tracking an unknown number of targets that move close and/or cross each other in a dense environment. The optimal Bayes MTT problem is formulated in the Random Finite Set framework and Particle Markov Chain Monte Carlo (PMCMC) is applied to compute the multi-target posterior distribution. The PMCMC technique is a combination of Markov chain Monte Carlo (MCMC) and sequential Monte Carlo methods to design an efficient high dimensional proposal distributions for MCMC algorithms. This technique allows our multi-target tracker to handle high track densities in a computationally feasible manner. Our simulations show that under scenarios with a large number of closely spaced tracks the estimated number of tracks and their trajectories are reliable.
The efficient dispersion of powders in liquids is required in many fields. For this reason, it is... more The efficient dispersion of powders in liquids is required in many fields. For this reason, it is useful to understand the mechanisms of dispersion and the physical properties of powders which influence the dispersion rate. Here, we have chosen to work with a low fat cocoa powder commonly used in the food industry. Firstly, we have determined the physical properties of the powder (densities, cohesion, flowability, size and surface energy) and then measured the dispersion times of cocoa in water using a novel optical method. Further experiments, using the same technique, are performed using larger grains obtained by granulating cocoa powder. It is found that the dispersion times are shorter for the granules and much shorter than the dispersion time for ungranulated powder. The dispersion times for granules increase with the size of granules
This paper presents the MediaGrid project whose goal is the definition of a mediation framework f... more This paper presents the MediaGrid project whose goal is the definition of a mediation framework for transparent access to largely distributed sources. Frameworks are reusable pieces of design being expressed as a set of interfaces and components together with the description of their collaboration. Research topics addressed by the MediaGrid project include meta-data design, generation of mediation queries and adaptive and interactive query evaluation.
We propose a Bayesian multi-target batch processing algorithm capable of tracking an unknown numb... more We propose a Bayesian multi-target batch processing algorithm capable of tracking an unknown number of targets that move close and/or cross each other in a dense clutter environment. The optimal Bayes multi-target tracking problem is formulated in the random finite set framework and a Particle Marginal Metropolis-Hastings (PMMH) technique which is a combination of Metropolis-Hastings (MH) algorithm and sequential Monte Carlo methods is applied to compute the multitarget posterior distribution. The PMMH technique is used to design a high dimensional proposal distributions for the MH algorithm and allows the proposed batch process multi-target tracker to handle a large number of tracks in a computationally feasible manner. Our simulations show that the proposed tracker reliably estimates the number of tracks and their trajectories in scenarios with a large number of closely spaced tracks in a dense clutter environment albeit, more expensive than on-line methods.
Proceedings of the 2008 international symposium on Database engineering & applications - IDEAS '08, 2008
... query brokers Christophe Bobineau Grenoble Informatics Laboratory Grenoble Institute of Techn... more ... query brokers Christophe Bobineau Grenoble Informatics Laboratory Grenoble Institute of Technology Grenoble, France [email protected] Christine Collet Grenoble Informatics Laboratory Grenoble Institute of Technology Grenoble, France [email protected] ...
QBF: A Query Broker Framework for Adaptable Query Evaluation* Christine Collet and Tuyet-Trinh Vu... more QBF: A Query Broker Framework for Adaptable Query Evaluation* Christine Collet and Tuyet-Trinh Vu LSR-IMAG Laboratory, INP Grenoble BP 72, 38402 Saint-Martin d'Heres, France {Christine. Collet, Tuyet-Triah. Vujfflimag. fr Abstract. We present QBF (Query Broker ...
Proceedings. International Database Engineering and Applications Symposium, 2004. IDEAS '04.
This paper shows how to provide adaptable query eval-uation using QBF, a Query Broker Framework t... more This paper shows how to provide adaptable query eval-uation using QBF, a Query Broker Framework that pro-vides a set of tools facilitating the design and implemen-tation of query function in data-intensive distributed appli-cations. The framework allows the use of multiple mech- ...
T he efficient dispersion of powders in liquids is required in many fields. However, there are on... more T he efficient dispersion of powders in liquids is required in many fields. However, there are only a few studies on the physicochemical properties of the powders and the dispersion rate. The process of dispersing an agglomerated powder is mainly controlled by the forces acting between the primary particles, and between particles and liquid. In this paper, we present an experimental study of the dispersion kinetics of a hydrophobic powder (cocoa) in water. We firstly determined the surface free energy of the powder using several methods (static wettability, dynamic wettability). Interpretation of calculated values of spreading coefficients and interaction parameters revealed no energetically favoured cocoa-water interactions. A series of dispersion experiments were conducted in a stirred vessel to investigate the influence of stirring speed, temperature and concentration of powder in water. The dispersion concentration was measured using an optical scattering method, which was shown to give good information for evaluating the dispersion process. The experimental data fit an exponential mathematical model with two parameters (A, a): X(t) ¼ A[1 2 exp(2at)]. It was found that the rate of dispersion depends on the agitation speed with a critical speed 630 rpm. All results are discussed as a function of the agitation speed and temperature.
Proc. of the Conference RIVF, Hanoi, Vietnam, 2003
Abstract This paper presents our work on supporting flexi-ble query evaluation over large distri... more Abstract This paper presents our work on supporting flexi-ble query evaluation over large distributed, heterogeneous, and autonomous sources. Flexibility means that the query evalua-tion process can be configured according to application context-specific, ...
Uploads
Papers by Tuyet Vu