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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Conception pluridisciplinaire d’une méthode générale d’évaluation des flux de contaminants issus des ruissellements des matériaux de toitures à l’échelle urbaine : développement et illustration à partir du cas du zinc à Créteil / Multidisciplinary design of a general method for modelling roofing materials emissions on the city scale : development and illustration for zinc in the city of Créteil

Sellami, Emna 25 June 2014 (has links)
Ce travail de thèse vise à développer une méthode générale d'évaluation des flux de contaminants issus des ruissellements des matériaux de toiture à l'échelle urbaine. Cette méthode est fondée sur une démarche originale de changement d'échelles intégrant différents outils relevant des sciences de l'ingénieur et des sciences sociales. Le travail comprend la création d'une base de données bibliographique qui permet de disposer d'une vision synoptique des matériaux de toiture nouveaux et anciens utilisés à l'échelle urbaine, ainsi que des contaminants associés. La démarche de changement d'échelle – du toit à l'échelle urbaine – repose sur la notion de situation-type d'émission d'un contaminant par un matériau de toiture à laquelle est associé un flux unitaire unique. Cette notion propose une nouvelle définition de l'émission à l'échelle du toit incluant uniquement les paramètres pertinents à l'échelle urbaine. Afin de faciliter le calcul du flux à l'échelle urbaine, différents principes méthodologiques sont adoptés pour exploiter des bases de données urbaines existantes (base des modes d'occupation du sol, cadastre, images aériennes) et les adapter ou les interpréter au prisme de la problématique particulière des émissions de toitures. Ainsi, les principes de découpage et de croisement sont utilisés pour diviser l'échelle urbaine en entités homogènes. Une entité consiste en un regroupement de bâtiments, caractérisée par une répartition propre de matériaux de toitures. Ces entités sont obtenues en croisant une étude typologique des bâtiments (élaborée à partir de la base des modes d'occupation du sol) avec l'histoire urbaine et avec l'histoire des matériaux de toiture. La définition d'un ensemble de règles empiriques est nécessaire pour permettre la quantification des matériaux des différents éléments de toitures à l'échelle de la ville. Ces règles sont élaborées à partir d'une enquête et d'entretiens menés auprès d'experts des matériaux de toitures (fabricants, syndicats…) ainsi que d'une étude historique et d'une étude du marché des matériaux de toiture.Le développement intégral de la méthode jusqu'au calcul final rend indispensable le choix d'un terrain d'étude et d'un contaminant afin d'en illustrer en détail toutes les étapes de calcul. La ville de Créteil a été choisie car elle présente une mixité urbaine et historique suffisante pour embrasser la plupart des situations urbaines susceptibles d'être rencontrées en France. Elle offre également l'avantage de disposer d'un maximum de situations-types d'émissions renseignées pour le contaminant zinc qui a donc été retenu. Complétant les règles empiriques générales, une méthode statistique est développée sur ce cas d'étude. Croisée à une interprétation visuelle des matériaux de toiture à partir des images aériennes, elle permet d'évaluer la distribution des matériaux de toiture à partir d'un échantillonnage aléatoire simple de bâtiments appliqué à chaque entité homogène de la ville. Le couplage de cette distribution avec les situations-types concernées permet alors une estimation du flux de zinc émis par l'ensemble des toitures de Créteil, à savoir 813 kg.an-1 avec une incertitude de 16,6%.La méthode élaborée est généralisable à d'autres villes et d'autres contaminants. Dans cette optique, la démarche opérationnelle à suivre a été formulée de manière synthétique en fin de travail. Son utilisation peut permettre, d'une part d'évaluer à coût réduit l'impact des toitures d'une métropole ou d'une zone urbanisée sur l'environnement et, d'autre part, d'orienter les pratiques de gestion et l'utilisation des eaux de ruissellement en limitant l'apport de contaminants par les matériaux de toitures. Afin de pouvoir appliquer cette méthode à tout contaminant, des pistes ont été dressées pour définir une approche optimisant l'acquisition de données de flux annuels unitaires pour les différentes situations-types / This thesis aims to develop a general method for modelling roofing materials emissions on the city scale. This method is based on an original scaling approach integrating different tools within the engineering sciences and social sciences. The work includes the creation of a bibliographic database describing new and old roofing materials and their associated contaminants.The scaling approach - from roof to the city scale – is based on a new concept called typical-situation of contaminant emission from roofing material on the roof. For each typical situation a contaminant annual runoff rate is associated. This concept allows the transition between the roof scale and the city scale. To facilitate contaminant flow calculation on the city scale, different methodological principles are adopted to exploit and adapt existing urban databases (land use database, numerical cadastre, and aerial images) with respect to the specific issue of roofing material emissions. Thus, dividing and crossing principles are used to divide the city into homogeneous units. A unit is a cluster of buildings characterized by a specific roofing materials distribution. These units are obtained by crossing a typological buildings study (developed from the land use database) with the city urban history and the roofing material historical evolution. Defining empirical rules is necessary to quantify the distribution of the material in the different roofing elements on the city scale. These rules are developed from a survey made by conducting interviews with experts of the roofing material sector (industrials, masters of work, architects...) as well as a historical study and a market study for roofing materials.The full development of the method makes it essential to choose a study site and a contaminant in order to illustrate in detail all the calculation steps. Créteil city was selected because it presents a big diversity and a large number of buildings in order to represent most of the urban functions of any city in France. In the city of Créteil, zinc annual runoff rates have been produced for different metallic materials for the maximum of zinc typical-situation. A statistical approach was developed to complete empirical rules to compute roofing materials area distribution on the city scale. This approach is based on a stratified random sampling technique in conjunction with aerial images interpretation of the different roofing material element applied for each unit. Given the roofing material distribution and the zinc typical-situations, annual zinc flow from roofing material at Créteil city was estimated namely 813 kg.an-1 with an uncertainty of 16.6%.The developed method can be applied to other cities and other contaminants. In this context, the operational procedure of the application of this method was described at the end of this work. Our method can be used as a decision-making tool by urban planners at three levels to implement policies in order to reduce roofing pollutants emissions. In order to apply this method to any contaminant, different tracks were drawn to define an optimized approach to produce of runoff rates for different typical situations
12

Investigating the possibility of Jakobsgårdarna district in Borlänge, Sweden becoming a Positive Energy District (PED)

El Sawalhi, Rayan January 2022 (has links)
Climate change is a global phenomenon that strongly affect cities and urban areas. Due to the intensive industrial activities and global population growth leading to more fossil energy demands for the last century, the global warming effect appeared to have been significantly exacerbated. To overcome the issues related to the increase of greenhouse emissions amplifying the global warming, multiple initiatives and engagements have appeared for the last 10 years in order to reduce our global energy demands and reduce the dependency to fossil energy and engage a transition to renewable energy. One way to achieve these objectives is to engage a technological and societal shift in the building industry by reducing energy demands and increasing local energy productions based on renewable energy or, at least, carbon neutral systems. In order to qualify these new types of construction, the concept of positive energy district (PED) has arisen through multiple initiative around the world. This thesis aims to assess the possibility to meet the PED requirements for the new Jakobsgardarna district extension project proposed by Sweco in Borlange, Sweden. This project is based on 144 buildings composed of schools, residentials, retails shop, and offices spread on an 80 ha of land. The Building Energy Modelling (BEM) has been performed on IDA ICE to assess the energy demands and energy production of the entire district following multiple scenarios. These simulations have been performed with either a district heating system or a heat pump as base system. Then, the models have been extended with photovoltaic (PV) panel in multiple configurations in order to find the bes tsolution to meet the PED requirements. First results of the baseline configuration (district heating) shows that the yearly energy demand was around 14,227 MWh which represent almost 69 kWh/m2, mainly dominated up to 75% by the heating demands including domestic hot water (DHW). Moreover, an uncomfortable situation has been met in almost all residential building during summer with temperature reaching up to 31°C. The second configuration considering a heat pump with bore holes in replacement of the district heating shows an overall yearly energy demands of 9,738 MWh representing 47.2kWh/m2 per heated area. This results in a 67% reduction of the energy demands in comparison with the base case. This is due to the high coefficient of performance (COP=4) of the heat pump compared to the district heating system’s (COP=1). In this configuration the heating demands still corresponds to 70% of the overall energy demands. The addition of PV panels compensated the entire electrical needs of the district when combined with district heating and even allowed to reach the positive energy requirements when combined with heat pumps with bore holes. The latter case generates up to 20% of electrical energy in excess of what it produced, even while considering solar panels at a15° of tilt angle in a region where the optimal inclination is defined at 45°. According to the preliminary results obtained in this study, positive energy requirements could be met by the combination of heat pump and PV panels according to our assumptions. This work could then be used to further refine the district design and propose suggestions to improve both the thermal modeling of the district and the design rules for architects and local stakeholders.
13

Simulating the atmospheric primary and secondary organic aerosols / Μοντελοποίηση των πρωτογενών και δευτερογενών οργανικών σωματιδίων της ατμόσφαιρας

Τσιμπίδη, Αλεξάνδρα 14 December 2009 (has links)
Until recently, organic particulate material was simply classified as either primary or secondary with the primary component being treated in models as nonvolatile and inert. This framework is used to simulate the organic aerosol formation, growth and composition in the eastern United States during the four seasons of the year. The model predictions are evaluated against daily average PM2.5 (particulate matter smaller than 2.5 μm) measurements taken throughout the eastern United States by the Interagency Monitoring of Protected Visual Environments (IMPROVE) and the Speciation Trends Network (STN) monitoring networks. The performance of the model in reproducing organic mass concentrations is average during all four seasons of the year. The agreement between the predicted and observed temporal profiles suggests a reasonable understanding and depiction in the model of the corresponding processes. However, this oversimplified view fails to explain the observed highly oxygenated nature of ambient organic aerosols (OA), the relatively small OA concentration gradients between large urban areas and their surroundings, and the concentrations of OA during periods of high photochemical activity. To address the above issues new primary and secondary organic aerosol modules have been added to a three dimensional chemical transport model (PMCAMx) based on recent smog chamber studies. The new modeling framework is based on the volatility basis-set approach: both primary and secondary organic components are assumed to be semivolatile and photochemically reactive and are distributed in logarithmically spaced volatility bins. The resulting PMCAMx-2008 was applied in Mexico City Metropolitan Area (MCMA) for approximately a week during April of 2003. The model predictions are compared with Aerosol Mass Spectrometry (AMS) observations and their Positive Matrix Factorization (PMF) analysis. The final goal of this work is to provide information to the policy makers regarding the response of fine PM to emission controls. PMCAMx is used to investigate changes in PM2.5 concentrations in response to 50% emissions changes of oxides of nitrogen and anthropogenic volatile organic compounds during July 2001 and January 2002 in the Eastern United States. / Τα ατμοσφαιρικά οργανικά σωματίδια συνηθίζεται να χωρίζονται σε δυο κατηγορίες: πρωτογενή και δευτερογενή. Τα πρώτα εκπέμπονται κατευθείαν στην ατμόσφαιρα ενώ τα δευτερογενή δημιουργούνται με την μεταφορά μάζας αερίων χαμηλής πτητικότητας, που προκύπτουν από την οξείδωση πρωτογενών οργανικών αερίων, στα ατμοσφαιρικά σωματίδια. Ένα τρισδιάστατο χημικό μοντέλο (PMCAMx), βασιζόμενο σε αυτό το διαχωρισμό, χρησιμοποιήθηκε για την προσομοίωση της σύνθεσης και της μάζας των οργανικών σωματιδίων της ατμόσφαιρας, στις ανατολικές Ηνωμένες Πολιτείες της Αμερικής κατά τη διάρκεια των τεσσάρων εποχών του χρόνου. Οι προβλέψεις του μοντέλου αξιολογήθηκαν έναντι μετρήσεων που πραγματοποιήθηκαν από τα δίκτυα παρακολούθησης IMPROVE και STN στις ανατολικές ΗΠΑ. Η απόδοση του μοντέλου, όσον αφορά τον προσδιορισμό της συγκέντρωσης των οργανικών ενώσεων κατά τη διάρκεια όλων των εποχών είναι ιδιαίτερα ικανοποιητική. Ωστόσο, αν και οι προβλέψεις του μοντέλου για τη συγκέντρωση της οργανικής μάζας είναι ενθαρρυντικές, δεν είναι ξεκάθαρο εάν το μοντέλο προβλέπει τις σωστές τιμές για τους σωστούς λόγους. Συγκεκριμένα το μοντέλο δεν μπορεί να εξηγήσει την πολύ οξυγονωμένη χημική μορφή των ατμοσφαιρικών οργανικών σωματιδίων όπως αυτή αποτυπώθηκε σε μετρήσεις πεδίου. Για να αντιμετωπιστούν τα ανωτέρω ζητήματα αναπτύσσουμε μια νέα μέθοδο προσομοίωσης των διεργασιών σχηματισμού και χημικής γήρανσης των πρωτογενών και δευτερογενών οργανικών σωματιδίων της ατμόσφαιρας, στο τρισδιάστατο χημικό μοντέλο PMCAMx βασιζόμενοι σε πρόσφατα πειραματικά δεδομένα. Στο νέο αυτό πλαίσιο μοντελοποίησης τόσο τα πρωτογενή, όσο και τα δευτερογενή οργανικά συστατικά θεωρούνται ότι είναι ημιπτητικά και φωτοχημικά ενεργά και κατανέμονται λογαριθμικά σε ομάδες ενώσεων διαφορετικής πτητικότητας. Το βελτιωμένο PMCAMx (PMCAMx-2008) έχει εφαρμοστεί στην ευρύτερη περιοχή της πόλης του Μεξικού για περίπου μια βδομάδα τον Απρίλιο του 2003. Οι προβλέψεις του μοντέλου συγκρίνονται με μετρήσεις φασματογράφου μάζας αεροζόλ και άλλες μετρήσεις που πραγματοποιήθηκαν κατά τη διάρκεια της καμπάνιας MCMA-2003. Τέλος το PMCAMx έχει χρησιμοποιηθεί για να μελετηθούν διεξοδικά οι αλλαγές στη συγκέντρωση των οργανικών σωματιδίων διαμέτρου έως 2.5 μm που προκύπτουν από αλλαγές των εκπομπών NOx και VOCs κατά τη διάρκεια των μηνών του Ιουλίου 2001 και του Ιανουαρίου 2002 στις ανατολικές Ηνωμένες Πολιτείες της Αμερικής.
14

大眾運輸導向發展類型與指標之研究 -以臺北都會區捷運系統為例 / A Study of Transit Oriented Development Station Types and Markers –Examples for Taipei Metropolitan Mass Rapid Transit System

羅育華, Lou, Yu Hua Unknown Date (has links)
臺北都會區的土地利用,受到周圍環境變遷的影響,造成都市迅速擴張,產生許多邊緣城市的問題,面對都市成長所造成的外部性,為了解決都市蔓延與都市再生的問題,國內有許多研究提倡大眾運輸導向發展 (Transit Oriented Development, TOD)的理念,依據交通部的統計資料,捷運的使用率逐年提高,而臺北都會區大眾捷運系統路網,自西元1988年起陸續全面動工,分別於1996年3月至2013年11月完工通車,屬於發展成熟的交通路網,TOD的發展模式與場站周邊土地使用息息相關,因此,本研究參考國內外相關文獻關於TOD規劃設計的要素,以臺北捷運系統已通車路網103個捷運場站周邊500公尺為範圍,界定出與TOD規劃相關聯的指標,依捷運場站特性區分出不同的場站類型,就各個不同類型的場站分別提出TOD規劃的策略。 依實證結果,本研究提出核心商業型捷運站應強調都市設計,降低建蔽率,以增加開放空間;轉運中心型捷運站建議加寬人行道寬度,進行土地整合,提供外部公共空間和步行系統的連通設施,周邊地區利用公有土地,開闢公共設施;行政服務型捷運站可以朝多元化休閒、公益、商業的需求方向規劃;鄰近都市型捷運站可以藉由都市計畫調整商業區的劃設比例,增加公共設施的開闢率,提高都市服務設施;地區服務型捷運站可著重於遊憩規劃,強調良好的都市環境設計、街道與公共設施,提供具質量的自然環境、行人連結道,改善鄰里社區轉乘或步行至車站的便利性與連結性;產業發展型捷運站應透過都市計畫調整土地使用分區,增加住宅、商業、公園、廣場、綠地等土地使用類型,對於老舊之工業區並運用市地重劃等方式轉型為住、商、休憩均可使用之土地發展型態。每種類型的場站都能發展成為TOD捷運場站,但是,必須運用TOD的發展特性,進行場站及周邊土地使用之調整規劃。本研究提供TOD的關聯指標,以這些指標,可以評估各類型捷運場站的TOD如何發展,另外,提供一個經驗性的檢證,探討採用TOD的運作方式,如何形塑不同車站區域的長期發展策略。 / The land usage within the metropolitan areas of Taipei has promoted the rapid expansion of the city due to environmental changes and causing problems for the neighboring satellite cities. In order to solve the question of city expansion and renovation, many within the nation have set forth the concept of Transit Oriented Development (TOD). According to statistical data from the Ministry of Transportation, usage of mass rapid transit has increased annually and since the start of the Taipei Metropolitan Rapid Transit System in 1988 with lines finished and operating respectively from March of 1996 to November of 2013, it has become a mature and steadily growing traffic network. The framework behind TOD and the land usage along the stations are tightly linked, hence this paper taking into account both national and international related research on TOD related factors, focuses on the surrounding 500 meters alongside each of the 103 stations within the Taipei Metropolitan Rapid Transit highlighting TOD planning related markers according to station types and setting forth strategies for TOD planning. According to results, this research suggests that core business stations should emphasize city planning in order to lower building obstructions hence increasing open spaces; transit stations are suggested to increase the width of pedestrian walks providing open access to public areas; public service stations can follow a multi-directional approach based on recreation, philanthropy, and business; suburban stations can adjust business sector ratios to increase the area of public facilities with the application of city planning; local area stations can focus on leisure with emphasis on city environmental planning in regards to streets and public facilities providing a quality natural environment and pedestrian walkways improving the convenience of transfers and traffic to or from stations; industrial development stations should adjust land allocation through city planning increasing the number of residential dwellings, businesses, parks, squares, green areas, and so forth, but older industrial areas can be transformed for residential, business, or leisure purposes via methods such as rezoning to become land development models. Every type of station has the potential to become a TOD transit station, but measures must take into account the developmental characteristic of TOD to carry out station or adjoining land usage planning. This research provides TOD related markers to evaluate future development of transit stations and additionally first-hand verification of how the appliance of TOD can shape long term development strategy for different forms of transit areas.

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