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Urban Regeneration of Large Housing Estates in Europe: Hamburg and Niš Narratives
Get PDFAs a response to rapid urbanization, the construction and expansion of Large Housing Estates (LHEs) have played a significant role in housing provision throughout Europe. The provision and allocation of housing varies greatly among countries, particularly between the Western and Central and Eastern Europe. These differences can be referred to the different political and economic approaches and regimes. In Western Europe, the rapid expansion of large, post-war housing estates occurred as a response to cover the shortages in housing stock after WWII. These housing developments were constructed mostly at city outskirts and overtime have been concerned with social decline due to the concentration of lower-income, vulnerable and marginalized groups of people complemented with cuts in public expenditure and liberalization. As a result, LHEs face often-social problems and are viewed with skepticism and negativism. In contrast, in Central and Eastern Europe and particularly in former socialist countries, LHEs are still seen as a desirable housing environment until today. Nevertheless, there have been great concerns as well as the decline of LHEs in the post-socialist era. These concerns are focused on issues related to ownership and lack of maintenance, as a result of the political, economic and social transition of post-socialist countries. On the micro-level of housing projects, residents and local actors have been interpreting marketization into their daily practices and decisions, which shaped different LHEs transformation types.
In post-socialist Serbia, as in other transition countries, the city of Niš has experienced the same urban regeneration challenge of LHE. The former state-owned property was privatized to the sitting tenants in a low price form. The rapid withdrawal of the state from housing sector in the early phase of transition raised a set of issues, and led to different transformation types, such us, new infill housing and commercial development, expansion of multi-storey extensions, transformation and adaptation of garages and increase in commercial functions ''garage capitalism'', the quantitative and qualitative decrease of public open spaces, as well as a wide range of individual, building-based transformation. Difficulties to afford flats maintenance and renovation, as well as to refurbish entire blocks, are also present.
The participation of society is necessary for the successful implementation of integrated and sustainable development concepts. This document presents oral and visual narratives from Niš and Hamburg and reflects on both experiences in an effort to better understand the complexities of urban transformation in post-socialist cities, and to link them to the urban renewal processes of those similar in Western European cities
Prototypology for a circular building industry: the potential of re-used and recycled building materials
Get PDFThe growing scarcity of resources calls for a paradigm shift from linear material consumption to circular economy – especially in the construction industry. This shift involves a complete rethinking of design principles, materials, construction technics and technologies, as well as the introduction of new business models evolving from these reconfigurations within the field. This paper will show on-going research on these themes with a focus on direct material re-use and recycling through the discussion of a prototypology – the recently concluded Mehr.WERT.Pavillon (MWP) at the BUGA 2019 in Heilbronn. The research specifically addresses a reversible, mono-material structure that is made from re-used structural steel and recycled glass. The concept of cycles therefor is significant: Utilized materials are not consumed and disposed of; instead, they are borrowed from their material cycle for a certain period of time and later returned there at equal value and utility. Sourced from recycled materials, the prototypology is a built example of urban mining; designed for disassembly at the end of its service time, it also represents a material banks for future projects – while proofing the claim, that it is possible already today to build within a circular system
PCCT: A Point Cloud Classification Tool to Create 3D Training Data to Adjust and Develop 3D ConvNet
Get PDFPoint clouds give a very detailed and sometimes very accurate representation of the geometry of captured objects. In surveying, point clouds captured with laser scanners or camera systems are an intermediate result that must be processed further. Often the point cloud has to be divided into regions of similar types (object classes) for the next process steps. These classifications are very time-consuming and cost-intensive compared to acquisition. In order to automate this process step, conventional neural networks (ConvNet), which take over the classification task, are investigated in detail. In addition to the network architecture, the classification performance of a ConvNet depends on the training data with which the task is learned. This paper presents and evaluates the point clould classification tool (PCCT) developed at HCU Hamburg. With the PCCT, large point cloud collections can be semi-automatically classified. Furthermore, the influence of erroneous points in three-dimensional point clouds is investigated. The network architecture PointNet is used for this investigation
AVANTPARK – draußen *urban* angeeignet
Get PDFStädte wachsen unaufhaltsam, Mieten steigen, Plätze und Freiräume werden knapp. Zwischen Studium, Nine-to-fi ve-Jobs oder der ständigen Erreichbarkeit steigt die Sehnsucht nach Alltagsausbrüchen, Erholung im Grünen und echter Freizeit inmitten der Hektik der Stadt.
Unser Magazin, die AVANTPARK, wirft einen vielseitigen Blick auf Hamburger Parks - mal klassisch, mal um die Ecke gedacht. Sie gibt Anstöße für die Aneignung der Stadt als Freizeitraum und hinterfragt gegenwärtiges und zukünftiges Konfl iktpotential zwischen Freizeit, Arbeit und Wohnen.
In unterschiedlichen Formaten nimmt sich die AVANTPARK den gesellschaftlichen Bedürfnissen nach Erholung, Ausgelassenheit und Adrenalin an.
Die Redaktion dieses Magazins hat sich aus einer Gruppe Studierender des Studiengangs Kultur der Metropole zusammengefunden, um den Versuch zu wagen, Themen der Urbanistik aus ihren unterschiedlichen Perspektiven zu erzählen, zu erklären und im Konkreten zu erkunden
Datenbasiert lernende und modellprädiktive Regelung für Heizungssysteme
Get PDFIm Gebäudebereich werden heutzutage rund 40 % der gesamten in Deutschland verbrauchten Energie, eingesetzt. Bis zu 80 % der verbrauchten Energie in Gebäuden wird für die Erwärmung des Gebäudes und die Warmwasserbereitung verwendet. Das bedeutet, dass der Heizungsanlage im Gebäude auf Grund des hohen Energieverbrauchs eine besondere Bedeutung zukommt. Durch den hohen Energieverbrauch ergibt sich auch ein entsprechendes Einsparpotential, welches unter anderem durch eine verbesserte Betriebsführung, z.B. durch die Verwendung neuartiger Regelungskonzepte, ausgenutzt werden kann.
Diese Arbeit beschäftigt sich mit der Frage, wie gespeicherte Messdaten, welche oftmals nur für Monitoringzwecke verwendet werden, für die Optimierung von Regelungen genutzt werden können. Die entwickelten Regler werden am Beispiel von Heizungsanlagen getestet und die Ergebnisse ausgewertet. Modellprädiktive Regelungen (model predictive control - MPC) haben sich als geeignet für Systemen mit Totzeiten erwiesen, zu denen Heizungsanlagen gehören. Durch die Nutzung eines Modells für den MPC kann das künftige Anlagenverhalten berechnet werden und auf Änderungen in den Umgebungsbedingungen, durch die Nutzung von Vorhersagen, frühzeitig reagiert werden. Der MPC löst ein Optimierungsproblem, welches eine Kostenfunktion minimiert unter Berücksichtigung des Anlagenverhaltens, welches durch das Model wiedergegeben wird. Ein Aspekt der Nutzung von Daten ist die Modellbildung für die prädiktive Regelung.
Anhand eines Beispiels einer Heizungsanlage werden zwei Regelungen vorgestellt, wie sie heutzutage verwendet werden. Auf der einen Seite der proportionale-integrale (PI) Regler und auf der anderen Seite ein linearer MPC. Der PI-Regler ist ein Standardregler, der in vielen Anwendungsbereichen genutzt wird, auch für Heizungssysteme. Die Ergebnisse werden für Vergleiche mit den weiteren Regelungen genutzt. Sowohl der PI-Regler, als auch der MPC verwenden für die Regelung eine Referenz. Eine geeignete Referenz zu finden kann mitunter aufwendig und schwierig sein.
Ein sogenannter EMPC (economic model predictive controller), nutzt auch ein Modell des Systems und löst ein Optimierungsproblem, allerdings ohne Verwendung einer Referenz. Stattdessen wird die Optimierung unter Randbedingungen ausgeführt welche durch die Anforderungen des Systems definiert werden. Für Heizungsanlagen können z.B. die Komfortbedingungen an die Raumtemperatur über die Randbedingungen abgebildet werden. Dieser Ansatz wird um zeitabhängige Randbedingungen und diskrete Stellsignale erweitert. Durch die diskreten Stellsignalen wird das Optimierungsproblem zu einem gemischt-ganzzahligen Problem und die Lösung wesentlich komplexer und zeitaufwendiger. Der EMPC wurde auf eine Heizungsanlage angewandt, die Simulationsergebnisse mit denen des linearen MPC verglichen und anschließend in einer realen Heizungsanlage implementiert.
Die vorgestellten prädiktiven Regelungen nutzen ein lineares Modell. Wenn die Beschreibung des Systemverhaltens durch ein lineares Modell nicht ausreichend genau ist, führt dies im Allgemeinen zu nichtlinearen Modellen. Eine Unterklasse der nichtlinearen Modelle bilden die multilinearen zeit-invarianten (multilinear time-invariant MTI) Modelle. Unter Verwendung von MTI Modellen wurde die Struktur des MPC Optimierungsproblems auf Konvexität untersucht. Es konnte gezeigt werden, dass das Optimierungsproblem für Unterklassen der MTI Systeme und bestimmte Vorhersagehorizonte konvex ist.
Ein weiterer Ansatz, um Messdaten zu verwenden, ist die iterativ lernenden Regelung (iterative learning control - ILC). Dabei nutzt ein ILC gespeicherte Daten, um das Stellsignal der nächsten Iteration zu berechnen. Es wurde ein datanbasierter ILC eingeführt und Kriterien für die Wahl eines gespeicherten Datensatzes definiert. Die Kombination eines datenbasierten ILC mit einem linearen MPC wurde vorgestellt, in Simulation getestet und anschließend in einem prototypischen Heizungssystem implementiert. Der datenbasierte ILC speichert die Daten von vergangen Iterationen. Um eine Anwendung auf Plattformen mit wenig Speicherplatz zu ermöglichen, wurden die Messdaten in einer Tensorstruktur gespeichert und die kanonisch-polyadische Tensorzerlegung angewandt. Es konnte gezeigt werden, dass die Berechnungen des Ähnlichkeitskriteriums für die Auswahl eines Datensatzes auf Basis des zerlegten Tensors erfolgen kann, wodurch der Speicherbedarf um ein Vielfaches gesenkt werden konnte.
Das heißt, in dieser Arbeit wurden Messdaten zum einen für die Modellbildung für prädiktive Regelungen verwendet um das zukünftige Verhalten des Systems zu berücksichtigen und zum anderen für die lernende Regelung, welche aufgrund der verwendeten Messdaten das vergangene Verhalten des Systems berücksichtigt. Die entwickelten Regelungen wurden auf Heizungssysteme angewandt und die Ergebnisse mit denen der Standardregelungen verglichen.Up to 40% of the total energy consumption in Germany is used in buildings. Up to 80 % of the total energy consumed by buildings is used for heating the rooms and supplying the buildings with warm water. This means that the heating system of a building consumes the larges part of the total energy demand of the building. The high energy consumption in the building sector results in a large potential for energy savings. This potential can be utilized by optimizing the building automation systems, e.g., using new control methods for the heating systems.
This thesis deals with the question how stored measurement data, which are often used for monitoring purposes only, can be used for optimizing the control strategies. The developed controllers will be applied to a heating system and the results will be evaluated. Model predictive methods are a suitable choice for the control of systems with delay times, such as heating systems. The model predictive controller (MPC) uses a model to calculate the future behavior of the plant, so that the controller can react early to changes in the environmental conditions. For heating systems, the weather forecast is used for the MPC. An MPC solves an optimization problem by minimizing a cost function with respect to the future behavior of the plant, represented by the model. One aspect of this thesis is the modeling of heating systems by using stored measurement data.
First, two control strategies for today’s applications will be introduced and applied to a heating system example. On the one hand the classical proportional-integral (PI) controller and on the other hand a linear MPC. The PI controller is a standard controller for many applications and also for heating systems. The simulation results will be used in the following for the comparison with other control methods. Both controllers use a reference trajectory. Finding a suitable reference can be difficult and time consuming.
An economic model predictive controller (EMPC) will be introduced next. The EMPC uses also a model of the system and optimizes a cost function, but without using any reference signals. That means, that no reference has to be defined and the optimization is solved with constraints. The constraints are defined by the system requirements, such as the comfort conditions of the room temperature for heating systems. Additionally, time dependent constraints were introduced and the possibility to use discrete input signals. The discrete input signals change the optimization problem to a mixed-integer optimization problem, which leads to more complex and time consuming computations. The EMPC was applied to a heating system and the simulation results were compared with the results of the linear MPC. A real-time implementation of the EMPC for a heating system of an office building was stated and the results are evaluated.
A linear MPC uses a linear model of the system. If the system description by a linear model is not accurate anymore, the modeling of the system leads, in general, to a nonlinear model. A subclass of the general nonlinear model class are the multilinear time-invariant (MTI) models. The structure of the MPC optimization problem was investigated with the assumption that an MTI model is used, with the focus on the convexity analysis of the optimization problem. It could be proven that the optimization problem is convex for a subclass of MTI systems and a restricted prediction horizon.
An iterative learning controller (ILC) is another approach to use measurement data for control. An ILC uses the stored data for the calculation of the input signal of the next iteration. A data-driven ILC was introduced as well as an element selector for choosing a stored data set. For the element selector an optimization problem was formulated. A combined data-driven learning MPC was presented and tested by an application example. This combined control approach was implemented for a prototype heating system. The data-driven ILC collects and stores the data of all historic iterations. The historic data was stored in a tensor structure and the canonical-polyadic (CP) decomposition method was applied to reduce the storage demand and enlarge the possible implementation platforms to hardware with limited storage capacities. It could be shown that the calculation of the similarity criterion for the choice of a historic data set can be
performed with the CP decomposed tensor, which leads to a significant reduction of the storage demand.
In this thesis, measurement data was used for the modeling process for predictive control methods to take the future behavior of the plant into account and for iterative learning control, which uses the measurement data to consider the past behavior of the system. The developed control methods were applied to a heating system and compared to the results with a standard controller
Nachhaltiges und integriertes Sanitärmanagement in Entwicklungsländern: Der Fall der informellen Siedlungen in Kabul
Get PDFAfghanistans Hauptstadt sowie größte Stadt Kabul ist überwiegend auf hauseigene sanitäre Versorgungssysteme angewiesen. In den Vororten Kabuls gibt es einige wenige dezentrale Abwassersysteme, die größtenteils von privaten Firmen errichtet worden sind, jedoch ohne ordnungsgemäße Kontrolle von Seiten der Regierungsbehörden betrieben werden. Zudem versorgt ein semi-zentrales Abwassersystem aus der Zeit der Sowjetunion im Zentrum der Stadt Kabul die angrenzenden Wohnblöcke der Region als sanitäre Einrichtung. In weiten Teilen der Stadt werden jedoch größtenteils Trocken-Latrinen oder Spültoiletten verwendet, die an eine Senkgrube oder Abwassertank angeschlossen sind.
In den Großstädten Afghanistans, einschließlich Kabul, stellt der Mangel an angemessenem Fäkalschlamm-Management ein großes und vor allem wachsendes Problem für die Bevölkerung dar. Jede Maßnahme im Bereich Abwassermanagement, insbesondere in der Stadt Kabul, sollte ein angemessenes Fäkalschlamm-Management System entwickeln sowie seinen Anwendungsbereich von der Haushaltsebene auf die gesamte sanitäre Versorgungskette ausweiten.
Der größte Teil der Stadt Kabul besteht aus ungeplanten und informellen Wohngebieten. Momentan werden einige Bestrebungen verschiedener nationaler und internationaler Organisationen angestellt, um die schlechte sanitäre Grundversorgung in Kabul zu verbessern. Diese Dissertation konzentrierte sich auf die als informell bezeichneten Stadtteile von Kabul, um einen nachhaltigen und integrierten Ansatz zum Thema nachhaltige Abwassersysteme zu definieren und die Verbindung mit einer flächendeckenden, städtischen Sanitärversorgung herzustellen. Unter Berücksichtigung der Typographie von Kabul, wurden unter anderem Haushaltsbefragungen in zwei verschiedenen informellen Siedlungen durchgeführt.
Diese Forschungsarbeit stellt die Nachhaltigkeitskriterien von SuSanA in den Mittelpunkt der Identifizierung zweckmäßiger Technologien sowie der Vorschläge für ihre Untersuchungsstandorte. Zudem wurden die Nachhaltigkeitskriterien für alle informellen Siedlungen von Kabul angewandt. Zu diesem Zweck wurden primäre Hygienesysteme anhand von Indikatoren und Maßnahmen ausgewählt, welche auf Grundlage der Nachhaltigkeitskriterien entwickelt wurden. Als Schlussfolgerung wurden drei primäre Hygienesysteme, darunter ein Würmer-Faulbehälter, eine „pour-flush pit“ und eine Trockentoilette, als die am besten geeigneten Hygienesysteme für die informellen Stadtteile von Kabul vorgeschlagen.
Basierend auf geophysikalischen, sozialen und städtischen Daten wurde Kabul City in vier Hygienezonen unterteilt, einschließlich formeller sowie auch informeller Bereiche. Als nächster Schritt wurde die Integration der Kabuler Sanitärzonen in stadtweite Sanitäranlage bewertet. Darüber hinaus wurden die Verknüpfungen der verschiedenen Komponenten umweltgerechter Sanitäranlagen anhand der vorgeschlagenen, nachhaltigen und integrierten Sanitärsystem diskutiert.
Der letzte Teil dieser Dissertation stellt einen Vergleich der Ergebnisse von Kabul mit den Ergebnissen anderer Studien zu den Städten Beirut und Erbil dar. Der Vergleich hat dabei unterstützt, eine Verallgemeinerung für Länder mit niedrigem Einkommen und ähnlichem Kontext hervorzuheben. Die Regierungen der Länder mit niedrigem Einkommen müssen sich in ihrer Gesellschaft mit der Bekämpfung der Armut und der Bereitstellung von Grundversorgung, einschließlich sanitärer Einrichtungen, befassen. Solche Bemühungen der Regierungen sollten eine hohe Priorität haben und sich auf die am stärksten gefährdeten sozialen Gruppen konzentrieren.Kabul City as the capital and largest Afghan city mostly relies on on-site sanitation. There are some decentralized sanitation systems in the suburbs of Kabul City constructed mostly by the private sector without any proper monitoring by the government authorities. There is also a major semi-centralized sewerage system in central Kabul constructed during the Soviet Era providing services to the apartment blocks in the area. The other parts of the city usually use raised-vault dry latrines or flush toilets connected to soak wells or septic tanks.
Lack of proper faecal sludge management is a growing concern in the main cities of Afghanistan including Kabul. Any sanitation intervention, especially in Kabul City should develop proper faecal sludge management, and expand its scope from the household level to the whole sanitation chain.
The major part of Kabul City is unplanned and informal areas. There are various efforts undertaken by different national and international organizations to improve the poor sanitation situation in Kabul City. This dissertation focused on Kabul’s informal areas to define and conceptualize a sustainable and integrated sanitation approach linked to the city-wide sanitation. Considering Kabul’s typology, household surveys in two different informal settlements were conducted.
This research put SuSanA’s sustainability criteria at the center of technology identification & suggestions for its study sites, and later for all of Kabul’s informal settlements. To do so, primary sanitation systems were selected in accordance with indicators & measures developed based on the sustainability criteria. As conclusion, three prioritized sanitation systems including vermidigester, pour-flush pit, and dry toilet were suggested as the most suitable sanitation systems for Kabul’s informal areas.
Based on geophysical, social, and urban services data Kabul City was divided into four sanitation zones including formal and informal areas. As the next step, integration of Kabul’s sanitation zones to the city-wide sanitation was evaluated. Furthermore, the interlinkages of the different components of environmental sanitation to the proposed sustainable and integrated sanitation system was discussed.
The last part of the dissertation is a comparison of Kabul’s findings with the results of the studies on Beirut and Erbil Cities. The comparison helped us to make a generalization for low-income countries with similar context. Governments of low-income countries need to address poverty alleviation and provision of basic services, including sanitation, in their societies. Such efforts by the governments should be prioritized and focused on the most vulnerable groups
Urban Regions Shifting to Circular Economy: Understanding Challenges for New Ways of Governance
Get PDFUrban areas account for around 50% of global solid waste generation. In the last decade, the European Union has supported numerous initiatives aiming at reducing waste generation by promoting shifts towards Circular Economy (CE) approaches. Governing this process has become imperative. This article focuses on the results of a governance analysis of six urban regions in Europe involved in the Horizon 2020 project REPAiR. By means of semi-structured interviews, document analysis and workshops with local stakeholders, for each urban area a list of governance challenges which hinder the necessary shift to circularity was drafted. In order to compare the six cases, the various challenges have been categorized using the PESTEL-O method. Results highlight a significant variation in policy contexts and the need for these to evolve by adapting stakeholders’ and policy-makers’ engagement and diffusing knowledge on CE. Common challenges among the six regions include a lack of an integrated guiding framework (both political and legal), limited awareness among citizens, and technological barriers. All these elements call for a multi-faceted governance approach able to embrace the complexity of the process and comprehensively address the various challenges to completing the shift towards circularity in cities
Influence of Viewing Field on Zoom Levels in Pedestrian Orientation Task Using Smartphones
Get PDFPsychological findings indicate that the scale of human perception has implications on optimal map design. According to the map-based orientation in the real environment, this viewing scale depends on the visual field and is graphically reproduced using zoom levels, which significantly influences the map display area on smartphones. However, it is still unclear how to determine these zoom levels in the pedestrian navigation application. The purpose of this article is to adapt the map display area to the location-related viewing field using a corresponding zoom level. This optimal map display area should make it easier for the pedestrians’ self-location and navigational decisions. The results of the experiments have shown that there was a close relationship between the viewing field and the zoom level on the smartphone. However, if the first decision point of changing direction was in the viewing field, the distance between the viewpoint (You-Are-Here point) and this decision point influenced the zoom level. Otherwise, this distance did not have any influence on the zoom level. In this case, the distance between the viewpoint and the local landmarks determined the zoom level
Driving factors of sustainable transportation: Satisfaction with mode choices and mobility challenges in Oxfordshire and Hamburg
Get PDFRecent decades have seen a shift towards more sustainable transport and support of more balanced development of all modes of transport by many governments, with scholarly articles contributing to the discourse. However, users’ attitudes and satisfaction with existing modes of transport determine ultimate acceptance of new transport opportunities. Inclusion of the public is also essential to make a change towards new and more sustainable mobility choices. Accordingly, travel satisfaction as a source of travel mode choice is a significant aspect in the analysis of urban mobility. Different travellers with varying mode choices have different needs and priorities, influencing appreciation of and satisfaction with various aspects of travel.
This paper investigates key factors influencing individual travel behaviours for different travel modes by examining the interactions of mode choice and traveller satisfaction with mobility challenges. Primary data were collected through online surveys conducted as a part of the EU-Horizon 2020-funded Cities-4-People project. Quantitative data were collected to analyse the socio-demographic charac- teristics of citizens moving daily in the city, their routes, mobility challenges and satisfaction with travelling. This paper presents the findings of the survey conducted in Hamburg-Altona (Germany) and Oxfordshire (UK).
Survey results confirm previous findings and contribute additional evidence suggesting that the main sources of satisfaction from sustainable transportation modes appear to be service quality and infrastructure. Deeper consideration of satisfaction by mode usage allows for some pronounced differences between user types to be analysed
Adaptive architecture as mediator between humans and earth
Get PDFIl contributo riporta alcune riflessioni sul potenziale dell’Architettura Adattiva come mediatrice, non solo tecnicamente ma anche socialmente ed esteticamente, fra gli uominie l’ambiente. La compensazione degli effetti del cambiamento globale attraverso l’Architettura non muta il comportamento umano; la sfida è quella di coinvolgere e muovere all’azione ciascun singolo abitante. Attuando il principio dell’adattamento in ogni dimensione, è possibile compiere un nuovo passo verso un rapporto più sano e reciproco fra gli uomini e la Terra. Attraverso un approccio olistico vengono discussi progettidel passato e contemporanei di Architettura e di Arte, presentando prospettive sistemiche, esplorative, sociali ed estetiche. Nel ruolo di mediatrice, l’Architettura Adattiva permette di sperimentare un sistema globale in ambito locale, aiutando i suoi abitanti amigliorare il proprio rapporto con la Terra.This paper describes the potential of adaptive architecture to mediate not only technically but also socially and aesthetically between humans and the environment. Compensating global change through architecture does not change human behaviour; the challenge is to involve and activate each inhabitant. By implementing the principle of adaptation in all dimensions, a step towards a healthy and resilient relationship between humans and earth can be taken. In this holistic approach, historical and contemporary projects in Architecture and Art are discussed and systemic, explorative, social and aesthetic perspectives are taken. As a mediator adaptive architecture makes a global system experienceable in the local, supports its inhabitants to improve their relationship to the Earth and adapt