Raksmey Phan | Ecole des Mines de Saint-Etienne (original) (raw)
Papers by Raksmey Phan
Annales des Mines - Responsabilité et environnement
2019 Winter Simulation Conference (WSC)
Considering the globally aging population, one of the main challenges the healthcare system would... more Considering the globally aging population, one of the main challenges the healthcare system would have to face is to help elderly people stay at home in good health conditions and as long as possible. Recent advances in technologies answer this need with Smart Homes and Ambient Assisted Living programs. Data collected by the sensors are labeled and used to monitor the inhabitant Activities of Daily Living (ADLs). This paper presents a new modeling framework of the smart home resident’s behavior that mimics his behavior on multiple aspects and is able to simulate the resident daily behavior. Our approach is illustrated by a real-life case study application. Results show that the presented framework enables the modeling of human behavior living alone in a smart home without prior knowledge on the inhabitant. Such results enable further research on frailty prediction through simulation.
2020 IEEE 16th International Conference on Automation Science and Engineering (CASE)
With the global population growing older and more vulnerable, healthcare systems are considering ... more With the global population growing older and more vulnerable, healthcare systems are considering new approaches to maintain people autonomous in their own homes. Recent advances in pervasive computing technologies have opened up new opportunities to unobtrusively monitor human behavior at home. Sensors data related to the activities of daily living (ADLs) performed by the inhabitant can be collected and labeled manually or by using activity recognition algorithms. The purpose of this work is to propose an approach for detecting changes (drift) in the inhabitant behavior in order to detect potential changes in the health-state of the inhabitant. Based on unsupervised clustering, our approach use activity starting time and duration as key features to detect changes between time periods. Variations from one behavior to another one can be identified for subsequent review or intervention by a healthcare professional. The relevance and the nature of the change are asserted using the clustering validation metric called Silhouette. Case study experiments on real life and simulated datasets suggest that some user's behavior can go through smooth or abrupt changes and that these changes can be highlighted using our approach.
HAL (Le Centre pour la Communication Scientifique Directe), 2020
La fragilité de la personne âgée est un syndrome clinique utile pour évaluer le risque de perte d... more La fragilité de la personne âgée est un syndrome clinique utile pour évaluer le risque de perte d'autonomie. D'après la Société française de gériatrie et de gérontologie, la fragilité reflète une diminution des capacités physiologiques de réserve qui altère les mécanismes d'adaptation au stress. La fragilité est un concept multidimensionnel (physique, sociale, cognitive, nutritionnelle, sensorielle et fonctionnelle) et son dépistage est nécessaire pour le maintien d'une personne âgée en bonne santé. D'importantes innovations technologiques ont été réalisées dans le domaine de la santé ces dernières années et plus particulièrement de la santé à domicile avec des habitats intelligents. Un habitat intelligent est une maison équipée de capteurs non invasifs dans le but de récolter des informations sur les activités effectuées par la personne âgée. Pour des personnes âgées vivant à domicile, l'utilisation de ces nouvelles technologies pourrait améliorer
2019 Winter Simulation Conference (WSC), 2019
An incisional hernia (IH) is a ventral hernia that develops after surgical trauma to the abdomina... more An incisional hernia (IH) is a ventral hernia that develops after surgical trauma to the abdominal wall, a laparotomy. IH repair is a common surgery that can generate chronic pain, decreased quality of life, and significant healthcare costs caused by hospital readmissions. The goal of this study is to analyze the clinical pathway of patients having an IH using a medico-administrative database. After a preliminary statistical analysis, a process mining approach is proposed to extract the most significant pathways from the database. The resulting causal net is converted into a statechart model that can be simulated. The model is used to understand times of occurrence of complications and associated costs. It enables the simulation of what-if scenarios to propose an improved care pathway for patients who are the most exposed, using in particular prophylactic mesh at the time of abdominal wall closure during a laparotomy on hospitalization costs and readmissions.
2017 Winter Simulation Conference (WSC), 2017
Health care system is one of the most critical units in case of disasters. Floods cause an increa... more Health care system is one of the most critical units in case of disasters. Floods cause an increase of emergency patient flow that may overwhelm hospital resources. In this paper, we present a simulation model that evaluates health care emergency plan and assesses the resilience of the Ile-de-France region in case of a major flood. We combined in the model the health care process with a Markov chain flood model. The results can be used to elaborate an optimized strategy for evacuation and transfer operations. We provide a case study on three specialties and quantify the impact of several flood scenarios on the health care system. Hospitals Capacity Flood risk ...
Une instance du probleme est un graphe, un ensemble F de sommets interdits et un ensemble R de so... more Une instance du probleme est un graphe, un ensemble F de sommets interdits et un ensemble R de sommets obligatoires. Nous montrons que construire un vertex cover, connexe ou pas, de taille minimale, contenant tous les sommets de R et aucun sommet de F, peut etre 2-approche (s'il existe). Nous montrons aussi que decider s'il existe ou pas un ensemble dominant independant contenant tout R et aucun sommet de F est NP-complet.
2018 IEEE Symposium Series on Computational Intelligence (SSCI), 2018
Readmission to the emergency department is an important indicator of the quality of care. By esti... more Readmission to the emergency department is an important indicator of the quality of care. By estimating the risk of readmission, measures may be taken and revisits avoided. In this study we use an optimization-based discriminant analysis model (DAMIP), in combination with different heuristics for feature selection, to predict emergency department readmission within 72 hours. For feature selection random search, particle swarm optimization, and tabu search are considered. The model offers the possibility to not classify some patients in order to ensure acceptable prediction accuracy. A balancing technique is used to generate balanced training sets to improve the prediction of the small readmission group.The proposed method is tested on French healthcare data including diagnosis-related group (DRG) and patient characteristics of over 12 million emergency stays, for which approximately 5% of the patients return within 72 hours to the emergency department. We compare the results to diff...
La fragilite de la personne âgee est un syndrome clinique utile pour evaluer le risque de perte d... more La fragilite de la personne âgee est un syndrome clinique utile pour evaluer le risque de perte d'autonomie. D'apres la Societe francaise de geriatrie et de gerontologie, la fragilite reflete une diminution des capacites physiologiques de reserve qui altere les mecanismes d'adaptation au stress. La fragilite est un concept multidimensionnel (physique, sociale, cognitive, nutritionnelle, sensorielle et fonctionnelle) et son depistage est necessaire pour le maintien d'une personne âgee en bonne sante. D'importantes innovations technologiques ont ete realisees dans le domaine de la sante ces dernieres annees et plus particulierement de la sante a domicile avec des habitats intelligents. Un habitat intelligent est une maison equipee de capteurs non invasifs dans le but de recolter des informations sur les activites effectuees par la personne âgee. Pour des personnes âgees vivant a domicile, l'utilisation de ces nouvelles technologies pourrait ameliorer
Nous présentons un travail réalisé en collaboration avec le Syndicat Intercommunal de Traitement ... more Nous présentons un travail réalisé en collaboration avec le Syndicat Intercommunal de Traitement des Ordures Ménagères (SICTOM) des Couze s et le laboratoire d’informatique (LIMOS) de Clermont-Ferrand. Nous avons été amenés à travailler sur le système d’information du SICTOM en faisant à la fois des propositions méthod ol giques et organisationnelles sur la gestion des chauffeurs, des congés et des camions. Le Systè me d’Information comprend un module de Recherche Opérationnelle modélisant le problème sou s la forme d’un PVRP (Periodic VRP). Les travaux sur les problèmes de tournées font rarement état du travail d’analyse des processus métiers de l’entreprise et de la collecte des données en am ont de la modélisation du problème, alors-même que cette partie est un préalable nécessaire à l'op timisation. L'objectif est de présenter notre reto ur d'expérience dans le domaine à la suite du travail ré lisé pour le SICTOM des Couzes.
2019 IEEE 15th International Conference on Automation Science and Engineering (CASE), 2019
With the global population growing older and more vulnerable, healthcare systems are considering ... more With the global population growing older and more vulnerable, healthcare systems are considering new approaches to maintain people autonomous in their own homes. Recent advances in pervasive computing technologies have opened up new opportunities to unobtrusively monitor human behavior at home. Sensors data related to the activities of daily living (ADLs) performed by the inhabitant can be collected and labeled manually or by using activity recognition algorithms. The purpose of this work is to propose an approach for detecting changes (drift) in the inhabitant behavior in order to detect potential changes in the health-state of the inhabitant. Based on unsupervised clustering, our approach use activity starting time and duration as key features to detect changes between time periods. Variations from one behavior to another one can be identified for subsequent review or intervention by a healthcare professional. The relevance and the nature of the change are asserted using the clustering validation metric called Silhouette. Case study experiments on real life and simulated datasets suggest that some user's behavior can go through smooth or abrupt changes and that these changes can be highlighted using our approach.
Operations Research for Health Care, 2021
Annals of Oncology, 2019
Background One third of early breast cancers (EBC) in women are diagnosed over 70 years (y) old. ... more Background One third of early breast cancers (EBC) in women are diagnosed over 70 years (y) old. In this population, clinicians look not only at EBC characteristics but also antecedents and comorbidities to determine the best treatment. Methods ConSoRe is a new generation data analytics solution using natural language processing and perform advanced data mining. It was used for data extraction from electronic patient record of 2048 patients (pts) of more than 70 years, operated for EBC in Centre Leon Berard since 1997. Patient and tumor characteristics, treatment and survival were extracted. Results Mean age was 75.5 y (range 70-100 y). Main comorbidities described were coronary heart disease: 340 pts (16,6%) and diabetes: 321 pts (15,7%). Distribution of body mass index (BMI) was under 18.5: 56 pts (3,3%), 18.5-25: 677 pts (39,6%); 25-30: 620 (36,3%) and over 30: 356 (20,8%). Mean tumor size was 23,5 mm (range 6 to 150), SBR grading was distributed as well: grade 1: 317 (17%) ; gra...
Expert Systems with Applications, 2016
This is a PDF file of an unedited manuscript that has been accepted for publication. As a service... more This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Highlights Investigating the TEE evaluation by predictive functions using smart-{phone, watch}. Using a personalized MET value in regard of the characteristics of participants. New activities classification model to obtain an TEE estimation. Gap less than 4% on both activities classification and TEE. Free Research application available on Google Play.
Les bases de données NoSQL, ou non relationnelles, procèdent d'une logique différente du modè... more Les bases de données NoSQL, ou non relationnelles, procèdent d'une logique différente du modèle SQL pour stocker de très grands volumes de données de natures variées. Elles s'affranchissent des contraintes classiques et fournissent une architecture nouvelle, souple et performante. Le Big Data rassemble des technologies répondant aux 4 V : Volume important, Variété d'informations, Vélocité du traitement, Variabilité des sources. L'ouvrage s'emploie à rendre ces techniques accessibles. Il propose une présentation synthétique des systèmes de bases de données NoSQL dans une approche transversale sur plusieurs plateformes : NetBeans et Eclipse. Le propos est constamment illustré par de nombreux exemples implémentés sous forme de travaux pratiques utilisant : Oracle, MongoDB, Cassandra, Neo4j, Redi et Hbase. Des vidéos et des compléments gratuits sont disponibles sur le site web du livre : http://www.isima.fr/~lacomme/NoSQL/.
This paper introduces a predictive function for total energy expenditure (TEE) estimation of the ... more This paper introduces a predictive function for total energy expenditure (TEE) estimation of the current life using the embedded smartphone accelerometer sensor. Our research encompasses definition of an energy-saving function without any hypothesis on its initial relative position. Six 25-year-old highly graduate participants wore a smartphone in a front pants pocket and a valid Armband device for a day of a desk job. The performance of the proposed function is estimated by using our smartphone application and evaluated by comparing TEE given by the function with TEE of Armband device. The mean gap of TEE between our function and Armband was less than 15%. This work is a preliminary step forward definition of a new predictive function well tuned for representative French population. Our work is now directed on validation on a larger population sample.
Lecture Notes in Computer Science, 2013
Annales des Mines - Responsabilité et environnement
2019 Winter Simulation Conference (WSC)
Considering the globally aging population, one of the main challenges the healthcare system would... more Considering the globally aging population, one of the main challenges the healthcare system would have to face is to help elderly people stay at home in good health conditions and as long as possible. Recent advances in technologies answer this need with Smart Homes and Ambient Assisted Living programs. Data collected by the sensors are labeled and used to monitor the inhabitant Activities of Daily Living (ADLs). This paper presents a new modeling framework of the smart home resident’s behavior that mimics his behavior on multiple aspects and is able to simulate the resident daily behavior. Our approach is illustrated by a real-life case study application. Results show that the presented framework enables the modeling of human behavior living alone in a smart home without prior knowledge on the inhabitant. Such results enable further research on frailty prediction through simulation.
2020 IEEE 16th International Conference on Automation Science and Engineering (CASE)
With the global population growing older and more vulnerable, healthcare systems are considering ... more With the global population growing older and more vulnerable, healthcare systems are considering new approaches to maintain people autonomous in their own homes. Recent advances in pervasive computing technologies have opened up new opportunities to unobtrusively monitor human behavior at home. Sensors data related to the activities of daily living (ADLs) performed by the inhabitant can be collected and labeled manually or by using activity recognition algorithms. The purpose of this work is to propose an approach for detecting changes (drift) in the inhabitant behavior in order to detect potential changes in the health-state of the inhabitant. Based on unsupervised clustering, our approach use activity starting time and duration as key features to detect changes between time periods. Variations from one behavior to another one can be identified for subsequent review or intervention by a healthcare professional. The relevance and the nature of the change are asserted using the clustering validation metric called Silhouette. Case study experiments on real life and simulated datasets suggest that some user's behavior can go through smooth or abrupt changes and that these changes can be highlighted using our approach.
HAL (Le Centre pour la Communication Scientifique Directe), 2020
La fragilité de la personne âgée est un syndrome clinique utile pour évaluer le risque de perte d... more La fragilité de la personne âgée est un syndrome clinique utile pour évaluer le risque de perte d'autonomie. D'après la Société française de gériatrie et de gérontologie, la fragilité reflète une diminution des capacités physiologiques de réserve qui altère les mécanismes d'adaptation au stress. La fragilité est un concept multidimensionnel (physique, sociale, cognitive, nutritionnelle, sensorielle et fonctionnelle) et son dépistage est nécessaire pour le maintien d'une personne âgée en bonne santé. D'importantes innovations technologiques ont été réalisées dans le domaine de la santé ces dernières années et plus particulièrement de la santé à domicile avec des habitats intelligents. Un habitat intelligent est une maison équipée de capteurs non invasifs dans le but de récolter des informations sur les activités effectuées par la personne âgée. Pour des personnes âgées vivant à domicile, l'utilisation de ces nouvelles technologies pourrait améliorer
2019 Winter Simulation Conference (WSC), 2019
An incisional hernia (IH) is a ventral hernia that develops after surgical trauma to the abdomina... more An incisional hernia (IH) is a ventral hernia that develops after surgical trauma to the abdominal wall, a laparotomy. IH repair is a common surgery that can generate chronic pain, decreased quality of life, and significant healthcare costs caused by hospital readmissions. The goal of this study is to analyze the clinical pathway of patients having an IH using a medico-administrative database. After a preliminary statistical analysis, a process mining approach is proposed to extract the most significant pathways from the database. The resulting causal net is converted into a statechart model that can be simulated. The model is used to understand times of occurrence of complications and associated costs. It enables the simulation of what-if scenarios to propose an improved care pathway for patients who are the most exposed, using in particular prophylactic mesh at the time of abdominal wall closure during a laparotomy on hospitalization costs and readmissions.
2017 Winter Simulation Conference (WSC), 2017
Health care system is one of the most critical units in case of disasters. Floods cause an increa... more Health care system is one of the most critical units in case of disasters. Floods cause an increase of emergency patient flow that may overwhelm hospital resources. In this paper, we present a simulation model that evaluates health care emergency plan and assesses the resilience of the Ile-de-France region in case of a major flood. We combined in the model the health care process with a Markov chain flood model. The results can be used to elaborate an optimized strategy for evacuation and transfer operations. We provide a case study on three specialties and quantify the impact of several flood scenarios on the health care system. Hospitals Capacity Flood risk ...
Une instance du probleme est un graphe, un ensemble F de sommets interdits et un ensemble R de so... more Une instance du probleme est un graphe, un ensemble F de sommets interdits et un ensemble R de sommets obligatoires. Nous montrons que construire un vertex cover, connexe ou pas, de taille minimale, contenant tous les sommets de R et aucun sommet de F, peut etre 2-approche (s'il existe). Nous montrons aussi que decider s'il existe ou pas un ensemble dominant independant contenant tout R et aucun sommet de F est NP-complet.
2018 IEEE Symposium Series on Computational Intelligence (SSCI), 2018
Readmission to the emergency department is an important indicator of the quality of care. By esti... more Readmission to the emergency department is an important indicator of the quality of care. By estimating the risk of readmission, measures may be taken and revisits avoided. In this study we use an optimization-based discriminant analysis model (DAMIP), in combination with different heuristics for feature selection, to predict emergency department readmission within 72 hours. For feature selection random search, particle swarm optimization, and tabu search are considered. The model offers the possibility to not classify some patients in order to ensure acceptable prediction accuracy. A balancing technique is used to generate balanced training sets to improve the prediction of the small readmission group.The proposed method is tested on French healthcare data including diagnosis-related group (DRG) and patient characteristics of over 12 million emergency stays, for which approximately 5% of the patients return within 72 hours to the emergency department. We compare the results to diff...
La fragilite de la personne âgee est un syndrome clinique utile pour evaluer le risque de perte d... more La fragilite de la personne âgee est un syndrome clinique utile pour evaluer le risque de perte d'autonomie. D'apres la Societe francaise de geriatrie et de gerontologie, la fragilite reflete une diminution des capacites physiologiques de reserve qui altere les mecanismes d'adaptation au stress. La fragilite est un concept multidimensionnel (physique, sociale, cognitive, nutritionnelle, sensorielle et fonctionnelle) et son depistage est necessaire pour le maintien d'une personne âgee en bonne sante. D'importantes innovations technologiques ont ete realisees dans le domaine de la sante ces dernieres annees et plus particulierement de la sante a domicile avec des habitats intelligents. Un habitat intelligent est une maison equipee de capteurs non invasifs dans le but de recolter des informations sur les activites effectuees par la personne âgee. Pour des personnes âgees vivant a domicile, l'utilisation de ces nouvelles technologies pourrait ameliorer
Nous présentons un travail réalisé en collaboration avec le Syndicat Intercommunal de Traitement ... more Nous présentons un travail réalisé en collaboration avec le Syndicat Intercommunal de Traitement des Ordures Ménagères (SICTOM) des Couze s et le laboratoire d’informatique (LIMOS) de Clermont-Ferrand. Nous avons été amenés à travailler sur le système d’information du SICTOM en faisant à la fois des propositions méthod ol giques et organisationnelles sur la gestion des chauffeurs, des congés et des camions. Le Systè me d’Information comprend un module de Recherche Opérationnelle modélisant le problème sou s la forme d’un PVRP (Periodic VRP). Les travaux sur les problèmes de tournées font rarement état du travail d’analyse des processus métiers de l’entreprise et de la collecte des données en am ont de la modélisation du problème, alors-même que cette partie est un préalable nécessaire à l'op timisation. L'objectif est de présenter notre reto ur d'expérience dans le domaine à la suite du travail ré lisé pour le SICTOM des Couzes.
2019 IEEE 15th International Conference on Automation Science and Engineering (CASE), 2019
With the global population growing older and more vulnerable, healthcare systems are considering ... more With the global population growing older and more vulnerable, healthcare systems are considering new approaches to maintain people autonomous in their own homes. Recent advances in pervasive computing technologies have opened up new opportunities to unobtrusively monitor human behavior at home. Sensors data related to the activities of daily living (ADLs) performed by the inhabitant can be collected and labeled manually or by using activity recognition algorithms. The purpose of this work is to propose an approach for detecting changes (drift) in the inhabitant behavior in order to detect potential changes in the health-state of the inhabitant. Based on unsupervised clustering, our approach use activity starting time and duration as key features to detect changes between time periods. Variations from one behavior to another one can be identified for subsequent review or intervention by a healthcare professional. The relevance and the nature of the change are asserted using the clustering validation metric called Silhouette. Case study experiments on real life and simulated datasets suggest that some user's behavior can go through smooth or abrupt changes and that these changes can be highlighted using our approach.
Operations Research for Health Care, 2021
Annals of Oncology, 2019
Background One third of early breast cancers (EBC) in women are diagnosed over 70 years (y) old. ... more Background One third of early breast cancers (EBC) in women are diagnosed over 70 years (y) old. In this population, clinicians look not only at EBC characteristics but also antecedents and comorbidities to determine the best treatment. Methods ConSoRe is a new generation data analytics solution using natural language processing and perform advanced data mining. It was used for data extraction from electronic patient record of 2048 patients (pts) of more than 70 years, operated for EBC in Centre Leon Berard since 1997. Patient and tumor characteristics, treatment and survival were extracted. Results Mean age was 75.5 y (range 70-100 y). Main comorbidities described were coronary heart disease: 340 pts (16,6%) and diabetes: 321 pts (15,7%). Distribution of body mass index (BMI) was under 18.5: 56 pts (3,3%), 18.5-25: 677 pts (39,6%); 25-30: 620 (36,3%) and over 30: 356 (20,8%). Mean tumor size was 23,5 mm (range 6 to 150), SBR grading was distributed as well: grade 1: 317 (17%) ; gra...
Expert Systems with Applications, 2016
This is a PDF file of an unedited manuscript that has been accepted for publication. As a service... more This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Highlights Investigating the TEE evaluation by predictive functions using smart-{phone, watch}. Using a personalized MET value in regard of the characteristics of participants. New activities classification model to obtain an TEE estimation. Gap less than 4% on both activities classification and TEE. Free Research application available on Google Play.
Les bases de données NoSQL, ou non relationnelles, procèdent d'une logique différente du modè... more Les bases de données NoSQL, ou non relationnelles, procèdent d'une logique différente du modèle SQL pour stocker de très grands volumes de données de natures variées. Elles s'affranchissent des contraintes classiques et fournissent une architecture nouvelle, souple et performante. Le Big Data rassemble des technologies répondant aux 4 V : Volume important, Variété d'informations, Vélocité du traitement, Variabilité des sources. L'ouvrage s'emploie à rendre ces techniques accessibles. Il propose une présentation synthétique des systèmes de bases de données NoSQL dans une approche transversale sur plusieurs plateformes : NetBeans et Eclipse. Le propos est constamment illustré par de nombreux exemples implémentés sous forme de travaux pratiques utilisant : Oracle, MongoDB, Cassandra, Neo4j, Redi et Hbase. Des vidéos et des compléments gratuits sont disponibles sur le site web du livre : http://www.isima.fr/~lacomme/NoSQL/.
This paper introduces a predictive function for total energy expenditure (TEE) estimation of the ... more This paper introduces a predictive function for total energy expenditure (TEE) estimation of the current life using the embedded smartphone accelerometer sensor. Our research encompasses definition of an energy-saving function without any hypothesis on its initial relative position. Six 25-year-old highly graduate participants wore a smartphone in a front pants pocket and a valid Armband device for a day of a desk job. The performance of the proposed function is estimated by using our smartphone application and evaluated by comparing TEE given by the function with TEE of Armband device. The mean gap of TEE between our function and Armband was less than 15%. This work is a preliminary step forward definition of a new predictive function well tuned for representative French population. Our work is now directed on validation on a larger population sample.
Lecture Notes in Computer Science, 2013