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MTLM: a multi-task learning model for travel time estimation / Saijun Xu in Geoinformatica [en ligne], vol 26 n° 2 (April 2022)
Titre : MTLM: a multi-task learning model for travel time estimation Type de document : Article/Communication Auteurs : Saijun Xu, Auteur ; Ruoqian Zhang, Auteur ; Wanjun Cheng, Auteur ; Jiajie Xu, Auteur Année de publication : 2022 Article en page(s) : pp 379 - 395 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géomatique
[Termes IGN] analyse coût-avantage
[Termes IGN] apprentissage automatique
[Termes IGN] données d'entrainement (apprentissage automatique)
[Termes IGN] durée de trajet
[Termes IGN] modèle de simulation
[Termes IGN] transport collectif
[Termes IGN] transport intermodal
Résumé : (auteur) Travel time estimation (TTE) is an important research topic in many geographic applications for smart city research. However, existing approaches either ignore the impact of transportation modes, or assume the mode information is known for each training trajectory and the query input. In this paper, we propose a multi-task learning model for travel time estimation called MTLM, which recommends the appropriate transportation mode for users, and then estimates the related travel time of the path. It integrates transportation-mode recommendation task and travel time estimation task to capture the mutual influence between them for more accurate TTE results. Furthermore, it captures spatio-temporal dependencies and transportation mode effect by learning effective representations for TTE. It combines the transportation-mode recommendation loss and TTE loss for training. Extensive experiments on real datasets demonstrate the effectiveness of our proposed methods. Numéro de notice : A2022-325 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : https://doi.org/10.1007/s10707-020-00422-x Date de publication en ligne : 15/08/2020 En ligne : https://doi.org/10.1007/s10707-020-00422-x Format de la ressource électronique : URL article Permalink :
in Geoinformatica [en ligne] > vol 26 n° 2 (April 2022) . - pp 379 - 395[article]GIS analysis of the trafficability determined by slope in the eastern Tyrol front (WWI, Eastern Alps) : a military history reading / Mauricio Nicolas Vergara in Cartography and Geographic Information Science, Vol 45 n° 6 (November 2018)
Titre : GIS analysis of the trafficability determined by slope in the eastern Tyrol front (WWI, Eastern Alps) : a military history reading Type de document : Article/Communication Auteurs : Mauricio Nicolas Vergara, Auteur ; Aldino Bondesan, Auteur ; Francesco Ferrarese, Auteur Année de publication : 2018 Article en page(s) : pp 477 - 494 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications SIG
[Termes IGN] analyse coût-avantage
[Termes IGN] carte ancienne
[Termes IGN] carte militaire
[Termes IGN] fortification
[Termes IGN] pente
[Termes IGN] Tyrol (Autriche)
[Termes IGN] vingtième siècle
Résumé : (Auteur) In the autumn of 1914, Austria-Hungary began to prepare for the possibility of an Italian offensive by building field fortifications, which formed the Tyrol Defense Line (TDL). Mountainous areas, such as the area of the TDL, present obstacles to trafficability in large part caused by terrain slope. On the eastern Tyrol front, steep slope obstructed trafficability when the Italians attacked the TDL and represented, in turn, an advantage for the Austro-Hungarian defense. This paper focuses on the assessment of the conditions of trafficability determined by slope in the eastern Tyrol front, using a GIS cost distance analysis. Key sources were the maps of Austrian and Italian official histories, parameters derived mainly from Marinelli’s slope classification, and from the interpretation of the particular historical circumstances. The advantages and disadvantages were considered from the perspective of the defensive and offensive and their significance for the history of this conflict. In particular, these were related to the perimeter to be defended by alternative Austro-Hungarian lines. Numéro de notice : A2018-472 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/15230406.2017.1399828 Date de publication en ligne : 04/12/2017 En ligne : https://doi.org/10.1080/15230406.2017.1399828 Format de la ressource électronique : URL article Permalink :
in Cartography and Geographic Information Science > Vol 45 n° 6 (November 2018) . - pp 477 - 494[article]
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Code-barres Cote Support Localisation Section Disponibilité 032-2018061 SL Revue Centre de documentation Revues en salle DisponibleAssessing the economic value of 3D geo-information / Andrew Coote (01/11/2017)
Titre : Assessing the economic value of 3D geo-information Type de document : Rapport Auteurs : Andrew Coote, Auteur ; Phil Knight, Auteur ; Tina Svan Colding, Auteur ; et al., Auteur ; Frédéric Cantat , Auteur Editeur : Dublin : European Spatial Data Research EuroSDR Année de publication : 01/11/2017 Collection : EuroSDR official publication, ISSN 0257-0505 num. 68 Importance : 127 p. Format : 21 x 30 cm Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Information géographique
[Termes IGN] analyse coût-avantage
[Termes IGN] données localisées 3D
[Termes IGN] valeur économique
Index. décimale : 37.00 Géomatique - information géographique - infrastructure de données Résumé : (auteur) The use of 3D geo-information has rapidly developed in recent years. Technological advances have driven this evolution and reduced the costs involved in the procurement and processing of 3D geo - information. Consequently, National Mapping Agencies (NMA’s) are actively seeking to transform their data operations and processes to produce such enhanced products. However, budgetary constraints in the public sector necessitate a rigorous assessment of costs and benefits before opportunities can be developed. This report is the culmination of a EuroSDR project that undertook a business case analysis over 12 months in collaboration with 11 European national and regional mapping agencies.
The analysis undertaken was structured around use cases (in order to examine the value derived within specific business contexts) and employed two methodologies: (i) value chain analysis and (ii) cost - benefit analysis to identify the quantification of value add identified by value chain analysis and the assessment of costs.
Value chain analysis identifies the connections between the supply and demand sides of a product or service and qualitatively identifies the value that is added throughout the chain of processes from source to end-user. Cost - benefit analysis facilitates an estimation of Return on Investment (RoI) by quantifying the costs and quantifiable benefits that arise from an investment over a defined period of time.
The project’s stakeholders initially selected six use cases for study: forestry management, flood management, 3D cadastre and valuation, resilience (civil contingency), asset management and urban planning. Over the course of six different workshops value chain analysis was applied to each of these use cases. Out of this process, two use cases were then selected for quantification using cost-benefit analysis: flood management due to the ubiquity of the challenge and its high political profile, and urban planning as 3D geo - information has a significant potential to contribute to the problems of managing urban growth. The process ended with the findings and outcomes being shared and consolidated at a workshop attended by delegates from each stakeholder.
Urban planning cost-benefit analysis - the costs are based on real - world cost estimates from Denmark, scaled up for the Republic of Ireland using the comparative land areas. The benefits are based on the following examples of financial impacts (for urban areas only):
• Local Area Plan (LAP) revision and the impact on the planning authority • Visual impact assessment and the reduced costs for developers
• Reduced time for citizens to make LAP submissions and major scheme objections
• General improvements to public sector efficiency.
Based on a 10 year project life cycle and discount rate of 4%, the results indicate a benefit to cost ratio of 2.1:1 and Net Present Value of € 22 million.
Flood management cost-benefit analysis - the same financial model as was applied to the urban planning case was also used for flood management. However, three approaches were taken to “triangulate” the assessment and to illustrate the use of different methodologies:
Cost Avoidance (Option 1) - this estimates the damages and losses that could have been avoided had 3D geo - information been used rather than the information used currently. The avoided damages are then interpreted as the benefits of using 3D geo - information. It has the advantage of requiring only limited inputs and is based on data available from Switzerland: (i) historical information on the loss and damage from previous events and (ii) interviews 8 with experts to indicate the positive effects of a high accuracy DTM. This resulted in a benefit to cost ratio of 3.3:1 and Net Present Value (after 10 years) of € 8.9 million.
Case Study (Option 2) - this uses case study evidence from the Netherlands on public sector benefits from data sharing and the reduced costs of: (i) land survey work, (ii) failures resulting from earlier detection of design errors and (iii) environmental impact assessment s. This assessment gives a benefit to cost ratio of 3.2:1 and Net Present Value (after 10 years) of € 8.6 million.
Benefits Transfer (Option 3) - this uses information from a comparable study undertaken for USGS study entitled, ‘National Enhanced Elevation Assessment’ [Dewberry 2012]. Belgium has been used to illustrate this approach, although results for other countries involved in the study can also be automatically calculated within the financial model. This assessment method gives a benefit to cost ratio of 5.3:1 and Net Present Value (after 10 years) of € 27 million. The higher return calculated by this approach can be explained as Belgium would be unlikely to achieve the economies of scale of data capture costs in the US. A benefit to cost ratio “write down” of 50% would bring it into line with the returns predicted by the other two approaches.
The cost-benefit analysis demonstrated in both of the selected use cases that benefits outstrip costs by a multiple of between two and three times even when considering each use cases in isolation. As further applications of 3D geo–information are added, additional costs should rise more slowly, whilst benefits should accrue at a similar rate, thereby enhancing the overall rate of return. Investment proposals with the type of return profile found in this study would be expected to be positively received, provided the funds were available from public sources.
Further work using this methodology could usefully be considered in relation to the following use cases:
3D Cadastre and Valuation – in the consultant’s view this represents the best opportunity to complete cost - benefit analysis for one of the remaining use cases for which value chain mapping was undertaken. The timing of ground - breaking work in Denmark may mean that access to their internal economic assessment might now be publicly released making this a relatively quick and easy extension of the study into a potentially very financially attractive application.
Asset management – this should be approached by the creation of value chains for significant subsets of this large and complex use case, particularly transport asset management and streetworks. The recent study in Queensland may provide an opportunity for a cost - effective benefits transfer process to be applied.
Note de contenu : 1 INTRODUCTION
2 ECONOMIC CONCEPTS
2.1 The Value of Information
2.2 Methodologies used to assess the value of 3D geo-information in this project
3.2 Peer Review
3.3 Skill Transfers
4 VALUE CHAIN ANALYSIS RESULTS
4.1 Forest Management
4.2 Flood Management
4.3 3D Cadastre and Valuation
4.4 Resilience (civil contingency)
4.5 Asset Management
4.6 Urban Planning
5 COST-BENEFIT ANALYSIS RESULTS
5.1 Selected Use Cases for Cost-Benefit Analysis
5.2 Urban Planning
5.3 Flood Management
Numéro de notice : 17508 Affiliation des auteurs : IGN+Ext (2012-2019) Thématique : GEOMATIQUE Nature : Rapport nature-HAL : RappRech DOI : sans En ligne : http://www.eurosdr.net/sites/default/files/uploaded_files/pub68_economicvalue-3d [...] Format de la ressource électronique : URL Permalink :
Assessing the economic value ... - pdf éditeurAdobe Acrobat PDF
The confirmed realities and myths about the benefits and costs of 3D Visualization and virtual reality in discrete event modeling and simulation: A descriptive meta-analysis of evidence from research and practice / Ikpe Justice Akpan in Computers & Industrial Engineering, vol 112 (October 2017)
Titre : The confirmed realities and myths about the benefits and costs of 3D Visualization and virtual reality in discrete event modeling and simulation: A descriptive meta-analysis of evidence from research and practice Type de document : Article/Communication Auteurs : Ikpe Justice Akpan, Auteur ; Murali Shanker, Auteur Année de publication : 2017 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] analyse coût-avantage
[Termes IGN] interface utilisateur
[Termes IGN] quantité discrète
[Termes IGN] réalité virtuelle
[Termes IGN] simulation 3D
[Termes IGN] visualisation 3D
[Vedettes matières IGN] Géovisualisation
Résumé : (auteur) The past seventeen years has witnessed a significant transformation in discrete event modeling and simulation, and the introduction of new modeling methodology based on three-dimensional (3D) visualization and virtual reality (VR) technologies. While several studies demonstrate the benefits and costs of 3D and VR modeling in discrete event simulation (DES) based on empirical evidence, others rely on anecdotal evidence and experience from practice. Further, there are still some unsubstantiated claims about the gains and challenges arising from the application of 3D and VR technologies in DES. This paper synthesizes the realized benefits and costs associated with modeling and simulation in 3D and VR while differentiating the realities from claims (myths). The results show that 3D and VR techniques offer significant benefits in the major modeling and simulation tasks than speculated among practitioners in the simulation community. Numéro de notice : A2017-409 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1016/j.cie.2017.08.020 En ligne : https://doi.org/10.1016/j.cie.2017.08.020 Format de la ressource électronique : URL article Permalink :
in Computers & Industrial Engineering > vol 112 (October 2017)[article]The direction-constrained k nearest neighbor query dealing with spatio-directional objects / Min-Joong Lee in Geoinformatica [en ligne], vol 20 n° 3 (July - September 2016)
Titre : The direction-constrained k nearest neighbor query dealing with spatio-directional objects Type de document : Article/Communication Auteurs : Min-Joong Lee, Auteur ; Dong-Wan Choi, Auteur ; SangYeon Kim, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 471 – 502 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] analyse coût-avantage
[Termes IGN] classification barycentrique
[Termes IGN] contrainte de direction
[Termes IGN] données massives
[Termes IGN] index spatial
[Termes IGN] objet géographique
[Termes IGN] plus proche voisin, algorithme du
[Termes IGN] requête spatiale
Résumé : (auteur) Finding k nearest neighbor objects in spatial databases is a fundamental problem in many geospatial systems and the direction is one of the key features of a spatial object. Moreover, the recent tremendous growth of sensor technologies in mobile devices produces an enormous amount of spatio-directional (i.e., spatially and directionally encoded) objects such as photos. Therefore, an efficient and proper utilization of the direction feature is a new challenge. Inspired by this issue and the traditional k nearest neighbor search problem, we devise a new type of query, called the direction-constrained k nearest neighbor (DCkNN) query. The DCkNN query finds k nearest neighbors from the location of the query such that the direction of each neighbor is in a certain range from the direction of the query. We develop a new index structure called MULTI, to efficiently answer the DCkNN query with two novel index access algorithms based on the cost analysis. Furthermore, our problem and solution can be generalized to deal with spatio-circulant dimensional (such as a direction and circulant periods of time such as an hour, a day, and a week) objects. Experimental results show that our proposed index structure and access algorithms outperform two adapted algorithms from existing kNN algorithms. Numéro de notice : A2016-378 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1007/s10707-016-0245-2 En ligne : http://dx.doi.org/10.1007/s10707-016-0245-2 Format de la ressource électronique : URL article Permalink :
in Geoinformatica [en ligne] > vol 20 n° 3 (July - September 2016) . - pp 471 – 502[article]On the use of IT investment assessment methods in the area of spatial data infrastructure / Agnieszka Zwirowicz-Rutkowska in Geodesy and cartography, vol 65 n° 1 (June 2016)PermalinkEconomic assessment of the use value of geospatial information / Richard Bernknopf in ISPRS International journal of geo-information, vol 4 n°3 (September 2015)PermalinkGIS-ready sUAS / Jarlath P. M. O'Neil-Dunne in xyHt, vol 2015 n° 6 (June 2015)PermalinkBringing in GIS (3): benefits modelling / A. Davidson in GIM international, vol 22 n° 10 (October 2008)PermalinkGIS in response time analysis / M. Landre in GIM international, vol 22 n° 2 (February 2008)PermalinkEtude sur la vulnérabilité des territoires essonniens face au risque inondation / Jean-Philippe Ast (2008)PermalinkMultistate supernetwork approach to modelling multi-activity, multimodal trip chains / Theo Arentze in International journal of geographical information science IJGIS, vol 18 n° 7 (november 2004)PermalinkIntérêt de la fusion d'images à haute résolution spatiale pour la classification de l'occupation du sol en milieu urbain / Yves Cornet in Revue internationale de géomatique, vol 14 n° 3 - 4 (septembre 2004 – février 2005)PermalinkAspects organisationnels des SIG / Stéphane Roche (2004)PermalinkMaking the trade-off between decision quality and information cost / S. De Bruin in Photogrammetric Engineering & Remote Sensing, PERS, vol 69 n° 1 (January 2003)Permalink