Dirk Ahlers

Dirk Ahlers
Norwegian University of Science and Technology | NTNU · Department of Architecture and Planning

Dr. rer. nat.

About

86
Publications
8,379
Reads
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821
Citations
Additional affiliations
April 2014 - present
Norwegian University of Science and Technology
Position
  • Researcher
April 2013 - March 2014
Norwegian University of Science and Technology
Position
  • PostDoc Position
January 2011 - December 2012
UNITEC - Central American Technological University
Position
  • Researcher and Lecturer

Publications

Publications (86)
Article
Full-text available
This article discusses early developments of the Positive Energy District (PED) concept, both in terms of its definition and of its implementation in real world demonstrators. Based on the specific challenges for creating an operational definition for the European +CityxChange project, the feasibility of creating a PED was practically explored by i...
Article
Full-text available
It is commonly assumed by the projects demonstrating concepts for positive energy districts in cities across Europe that citizens want and need to be involved in the development of these concepts as an essential condition for positive energy districts to be deployed successfully and to achieve the expected societal goals. Six different research and...
Article
Full-text available
It is assumed by the projects demonstrating Positive Energy District (PED) concepts in cities across Europe that citizens should want and need to be involved in the development of new energy concepts, such as PEDs for these concepts to be deployed successfully. Six different PED research and innovation projects are investigating the types and expec...
Article
LocWeb and TempWeb 2021 were the eleventh events in their workshop series and took place co-located on 12 th April 2021 in conjunction with The Web Conference WWW 2021. They were intended to be held in Ljubljana, Slovenia as a potentially hybrid event, but due to the pandemic, were fully moved online. LocWeb and TempWeb were held as one colocated s...
Article
Full-text available
The Positive Energy District (PED) concept is a localized city and district level response to the challenges of greenhouse gas emission reduction and energy transition. With the Strategic Energy Transition (SET) Plan aiming to establish 100 PEDs by 2025 in Europe, a number of PED projects are emerging in the EU member states. While the energy trans...
Article
Purpose-In smart cities pervasive systems are deployed by enterprises and stakeholders in municipalities to provide digital services to citizens. But cities are faced with the challenge of achieving system pluggability, mainly service integration due to numerous actors and systems needed for smart urban transformation. Hence, there is need to emplo...
Chapter
Full-text available
A key future challenge is to provide decentralized and sustainable energy (Rifkin 2011). Given that challenge, the theme of Post-Oil City asks how this can be accomplished for cities and regions which evolved using fossil fuels. The Horizon 2020 innovation project Positive City ExChange (+CityxChange) responds to this challenge and to the Sustainab...
Book
Full-text available
Positive Energy Districts (PEDs) are gaining importance, both as urban innovation labs and as concrete, on-the-ground projects for creating future proof, energy-positive and climate-neutral urban living environments. Where do they come from and why should one have one or more PEDs developed in one’s own city?
Article
LocWeb 2020 was the tenth workshop in the LocWeb workshop series at the intersection of location-based analytics and Web architecture and was held at The Web Conference, WWW 2020, on 21 st April 2020. The focus was on Web-scale services and systems facilitating location-aware information access as well as on Spatial Social Computing on the Web. The...
Article
Abstract Purpose- Electric Mobility as a Service (eMaaS) is suggested as a possible solution to ease transportation and lessen environmental issues by providing a collaborative transport sharing infrastructure that is based on Electric Vehicles (EVs) such as electric cars, electric bicycles, etc. Accordingly, this study proposes a multi-tier archit...
Article
Full-text available
A pragmatic and polity-focused solution for governing a smart city in the direction of sustainability is still missing in theory and practice. A debate about whether a smart city is a pragmatic solution for modern challenges or just a technology-led urban utopia is entangled with the vexed issue of governance. While ‘smart governance’ has drawn unp...
Article
Smart city has emerged as a universal term for the pervasive utilization of Information and Communication Technologies (ICTs) deployed to provide value-added services to citizens based on data generated from sectors such as energy, mobility, etc. However, current approaches are faced with interoperability as a challenging issue in processing big-da...
Article
Full-text available
The smart grid achieves bidirectional information and energy flow between energy consumer and utility grid, aiding energy users not only to utilize energy, but also to produce, sell, and share energy with other consumers or with the utility grid. This type of energy user is referred to as the "prosumer". Thus, prosumer management structures are imp...
Article
LocWeb 2019 was the ninth workshop in the LocWeb workshop series at the intersection of location-based services and Web architecture and was held at The Web Conference, WWW 2019, in San Francisco. It focused on Web-scale services and systems facilitating location-aware information access as well as on Spatial Social Behavior Analytics on the Web. T...
Article
Full-text available
A main challenge in building carbon-neutral built environments is the ability to scale and replicate solutions. We examine how to develop low-carbon neighbourhoods and districts, while aiming at climate-friendly and sustainable livable urban environments. We take a view that not only scales up individual building solutions, but embraces the added c...
Chapter
Smart city innovations can enhance the quality of citizens’ life through different smart technology management solutions, including resource management, data management, and software management. Nowadays, there are two primary proposals for smart technology management architectures in smart city environments, centralized, and distributed-to-central...
Conference Paper
As a part of their digital transformation, municipalities across Europe have taken initiatives to support Open Data platforms and provide services leveraging on data. This challenges the traditional business driven IT strategy promoted by several Enterprise Architecture methodologies, which are designed to operate within a single enterprise that ha...
Conference Paper
As a part of their digital transformation, municipalities across Europe have taken initiatives to support Open Data platforms and provide services leveraging on data. This challenges the traditional business driven IT strategy promoted by several Enterprise Architecture methodologies, which are designed to operate within a single enterprise that ha...
Chapter
As a part of their digital transformation, municipalities across Europe have taken initiatives to support Open Data platforms and provide services leveraging on data. This challenges the traditional business driven IT strategy promoted by several Enterprise Architecture methodologies, which are designed to operate within a single enterprise that ha...
Chapter
In this position paper we present IT-centered challenges that lie in designing an architecture for a flexible, open, transferable, and replicable smart city ecosystem spanning a plethora of suppliers and systems. The background is the smart city and energy project +CityxChange. Its vision is to enable the co-creation and development of Positive Ene...
Article
LocWeb 2018 continued the LocWeb workshop series at the intersection of location-based services and Web architecture and was held at The Web Conference, WWW 2018. It focused on Web-scale services and systems facilitating location-aware information access as well as on Spatial Social Behavior Analytics on the Web as part of social computing. The Loc...
Technical Report
Full-text available
This document outlines the definition, key performance indicators (KPI) and assessment criteria for the Research Centre on Zero Emission Neighbourhoods in Smart Cities (ZEN research centre). This first version of the ZEN definition includes contributions from the ZEN partners. In total, around 50 people involved in the ZEN research centre have cont...
Conference Paper
Full-text available
Smart cities attempt to use big data, machine learning, and other topical information and communication techniques (ICTs) to improve energy-consumption, mobility, waste management, and other crucial city functions. Many international research projects have been reported but, so far, few of them have addressed mobility in Norwegian cities specifical...
Conference Paper
It is our great pleasure to welcome you to the 8th International Workshop on Location and the Web (LocWeb2018) at WWW 2018. LocWeb 2018 will continue a successful workshop series at the intersection of location-based services and Web architecture. It focuses on Web-scale services and systems facilitating location-aware information access as well as...
Conference Paper
Full-text available
Cities worldwide aim to reduce their greenhouse gas emis- sions and improve air quality for their citizens. Therefore, there is a need to implement smart city approaches to monitor, model, and understand local emissions to better guide these actions. We present our approach that deploys a number of low-cost sensors through a wireless Internet of Th...
Conference Paper
New retrieval models promise deeper integration of multiple features and sources of information. The inclusion of thematic and location features in a joint factorization model allows location to be modeled as a first-class feature and can improve a range of tasks in geographic information retrieval and recommendation. In this position paper, we des...
Conference Paper
We examine the GeoNames gazetteer as a hub of Linked Geospatial Data. We survey quality and linkage characteristics to understand how well it supports the traversal of the Semantic Web and which limitations exist. We examine different traversal scenarios originating with GeoNames and present findings related to link availability and distribution al...
Conference Paper
We present CEST, a generic method for detection and rich summarization of events occurring in a city. CEST exploits Twitter metadata, does not need prior information on events, and is event category and structure agnostic. We developed CEST to process unstructured documents and take advantage of shorthand notations, hashtags, keywords, geographical...
Article
Location is an important feature in describing and understanding the real world. Consequently, it appears in many Web applications and mining approaches as a cross-cutting issue. LocWeb 2017 continues a workshop series addressing issues at the intersection of location-based services and Web architecture and was held in conjunction with WWW 2017. It...
Conference Paper
Business process modeling and business process management has been used to capture, support and improve a large variety of processes and practices in the private and public sector. Traditionally what is regarded as a good business process is strongly related to economic dimensions. With the increasing importance of assuring sustainable development,...
Article
Knowledge and information are valuable resources in enterprises for solution reuse. However, identifying relevant information from a rapidly growing number of unstructured resources is challenging for users. We discuss a personalized information access tool for professional workplaces based on recommender systems to provide relevant documents for u...
Chapter
Full-text available
Engineering is becoming more collaborative and increasingly global. However, inefficiencies in the communication and collaboration between engineers and engineering teams that are geographically distributed routinely cause competiveness and quality problems, as well as slowing the time to market for new innovations. Hence, networked knowledge excha...
Chapter
Full-text available
The LEAP collaboration system is a compilation of models, concepts, elements, and technology components that—when combined and structured in a meaningful way to teams of end users—enable companies to execute split-location engineering projects in a way that represents a competitive advantage. Written specifically for split-location and multidiscipl...
Article
For describing and understanding the real world, location is an important factor. Consequently, it also appears in many Web applications and mining approaches as a cross-cutting issue. LocWeb 2016 continues a workshop series addressing issues at the intersection of location-based services and Web architecture and was held at WWW 2016. It combines g...
Article
Full-text available
Cities are main drivers for climate change mitigation and emission reduction today. However, in many cases they lack reliable baselines of emissions to validate current developments over time, assess the impact of their projects, and prioritize investments and actions. They also need better data on a small geospatial and temporal scale to really un...
Conference Paper
Full-text available
Climate change is an important area of concern today. Yet it is often difficult for individuals to estimate their own climate footprint and to understand their personal climate impact. However, an activity tracking approach can help individuals to track and visualize their otherwise invisible climate impacts to better understand their personal impa...
Conference Paper
Full-text available
Urban mobility analysis usually examines large cities or even regions. We take another angle and examine a university campus as a city within a city to focus on small-scale and hyperlocal characteristics. The campus mobility data exhibits a high spatial and temporal granularity that we use to drive analyses and visualizations towards the aim of cam...
Conference Paper
Smart Cities denote a stronger integration of information technology into the organisation of a city and the interaction and participation of its citizens. In developing the concept further, we propose to understand Smart Cities through the lens of Social Machines and thus stronger focus on the city as a socio-technical construct. We draw from an i...
Article
Location is a major feature for describing the real world, appearing in many Web applications and search systems as a cross-cutting issue. Envisioning the establishment of an adequate venue for the location topic, LocWeb 2015 continued a workshop series at the intersection of geospatial search, information management, and Web architecture, with a m...
Conference Paper
We examine the notion of granularity for qualitative thinking about geospatial data and location references. Granularity can be understood as an abstraction of level of detail or spatial resolution. Pure coordinates, which may exhibit strong overprecision for some entities, can be combined with not only hierarchical gazetteer information, but also...
Conference Paper
This vision paper argues that a geospatial knowledge base combining textual descriptions for concepts such as places, together with place types, semantic relations between concepts and, most importantly, polygonal geometries associated to the geospatial concepts, constitutes a valuable resource for researchers working on the computational modeling...
Conference Paper
Geographical proximity is an important ranking feature in many context aware recommendation systems. News recommender systems are an example of such systems where the proximity between users and the news' geographical context is a particularly important relevance factor. In this paper, we will discuss ways to improve distance ranking by taking geog...
Article
Enterprise data is an amalgam of mostly semi-structured and unstructured data and documents stored in heterogeneous systems. The available structure is often not readily apparent or modelled to be useful. Formats such as PDF, DWG, Excel, or Word offer a high grade of flexibility; the issue is rather that their freeform content does not divulge its...
Conference Paper
Full-text available
In any larger engineering setting, there is a huge number of documents that engineers and others need to use and be aware of in their daily work. To improve the handling of this amount of documents, we propose to view it under the angle of a new domain for professional search, thus incorporating search engine knowledge into the process. We examine...
Conference Paper
Lots of professional collaborative work relies on shared networked file systems for easy collaboration, documentation, and as a joint workspace. We have found that in an engineering setting with tens of thousands of files, usual desktop search does not work as well, especially if the project space is huge, contains a large number of non-textual fil...
Article
Location is a major aspect behind many approaches in Information Retrieval, naturally appearing in diverse forms and as a cross-cutting topic. To give the location topic an adequate venue, LocWeb 2014 restarted a workshop series at the intersection of geospatial search, information management, and Web architecture, with a main focus on location-awa...
Article
The LocWeb 2014 workshop continues a successful workshop series at the intersection of geospatial search, information management, and Web architecture with a focus towards location-aware information access. The workshop reflects a multitude of fields that demand and utilize location features, featuring presentations that look at the topic of locati...
Conference Paper
Geographic search is routinely used in many services and applications that exploit the availability of Web content which is related to a real world place, region or object. However, do you trust the location information? Who has not made the experience that the restaurant you went to has just moved to another part of the city or shut down? Local se...
Article
This article reports on the efforts to establish a research project on a geospatial search engine for the Latin American country of Honduras during the author’s research stay at a local university. Honduras is an interesting example of the challenges for information and knowledge management in developing countries as it combines many of the issues...
Article
We examine the application of semantic context-aware Recommender Systems to improve interaction and navigation in a design-centric engineering domain. The small scale of this specialised environment renders most Web-scale solutions unsuitable, mandating tailored approaches. We report on initial work to identify challenges and promising categories o...
Conference Paper
Gazetteers are the basis of many geospatial applications and serve an important role to collect and make available knowledge about the physical world such as place names and their coordinates. GeoNames is one of the largest and most often used gazetteer and it is generally assumed to be of sufficient quality. In this paper, we examine the quality a...
Conference Paper
This paper gives a short overview of a project on Geographic Information Retrieval in developing countries in the form of an experience report based in Honduras. It provides some insights into encountered challenges of resource discovery, and georeferencing due to low Web coverage and informal location references as well as tested or proposed solut...
Conference Paper
Geospatial search as a special type of vertical search has specific requirements and challenges. While the general principle of resource discovery, extraction, indexing, and search holds, geospatial search systems are tailored to the specific use case at hand with many individual adaptations. In this short overview, we aim to collect and organize t...
Conference Paper
Different language versions of Wikipedia contain articles referencing the same place. However, an article in one language does not necessarily mean it is available in another language as well and linked to. This paper examines geotagged articles describing places in Honduras in both the Spanish and the English language versions. It demonstrates tha...
Conference Paper
Full-text available
The most common and visible use of geographic information retrieval (GIR) today is the search for specific points of interest that serve an information need for places to visit. However, in some planning and decision making processes, the interest lies not in specific places, but rather in the makeup of a certain region. This may be for tourist pur...
Article
Yellow pages have for a long time been the major providers of business' addresses and contact information. Nowadays, many people use local search engines for such information needs. Contrary to Web search, results for local search are expected to be much more precise and actually describe a pinpointed entity instead of giving out long result lists....
Conference Paper
Local search is a well-established mode of Web search engines today. For most developed countries, a huge amount of data is directly available on the Web and can be extracted and processed by search engines. In many developing countries, the Web coverage is much lower and only little information is directly available. To develop a Local Search that...
Chapter
Purpose — To provide a theoretical background to understand current local search engines as an aspect of specialized search, and understand the data sources and used technologies. Design/methodology/approach — Selected local search engines are examined and compared toward their use of geographic information retrieval (GIR) technologies, data source...
Conference Paper
Full-text available
Local Web search has become a major and popular means of gathering information with a geographic relation. Local search not only relies on powerful algorithms from Geographic Information Retrieval and other fields, but also on the broad availability of location-referenced data on the Web and in other sources. While available commercial systems work...
Chapter
Wer auf Hemingways Spuren durch das Montafon in Österreich wandert, kann sich über einen neuen Weggefährten freuen: Ein elektronischer Wanderführer kennt nicht nur zahlreiche attraktive Wanderwege, sondern verrät auch Wissenswertes über diese Alpenregion. Der mobile Wanderführer SmartGuide entstand im europäischen Projekt LOCCATA in einer Kooperati...
Article
Zusammenfassung Ein zukünftiges Fahrzeuginformationssystem mit Zugang zum Internet wird den Reisenden neue Dienste und Informationsangebote zur Verfügung stellen können. Im Gegensatz zur üblichen mobilen Nutzung des Internet stellt die Fahrzeugumgebung deutlich andere Anforderungen, bietet jedoch auch interessante Möglichkeiten, beispielsweise die...
Conference Paper
Within context-aware mobile applications, location information usually plays a major role for information selection and adaptivity. In this paper, we explore the geospatial dimension between simple position-aware and fully context-aware information systems by examining in-depth the features of spatial context beyond mere position. We describe how t...
Conference Paper
Location information on the Web is a precious asset for a multitude of applications and is becoming an increasingly important dimension in Web search. Even though more and more Web pages carry location information, they form only a small share of all pages and are scattered over the Web. To efficiently find and index location-related Web content, w...
Conference Paper
Geocoding is the conversion of a textual description of a location to geographic coordinates. With online geocoders being freely available to researchers and practitioners alike, their influence on data quality needs to be estimated. To this end, we first describe the basics of address-based geocod-ing and accuracy issues. We then look at two of th...
Conference Paper
Full-text available
Localization is a vital part of mobile applications. However, the quality of predominant GNSS-based localization remains inadequate for high-precision scenarios for mobile users. Based on previous work, we discuss the relevance of GNSS for mobile applications focusing in particular on mobile pedestrians. We present selected pedestrian-oriented appl...
Conference Paper
Full-text available
Web image search today is mostly keyword-based and explores the content surrounding the image. Searching for images related to a certain location quickly shows that Web images typically do not reveal their explicit relation to an actual geographic position. The geographic semantics of Web images are either not available at all or hidden somewhere w...
Conference Paper
Local search is increasingly becoming a major focus point of research interest. It is a widely-recognized speciality search with a large application area. Its data is usually aggregated from a variety of sources. One as yet largely untapped source of location data is the WWW. Today, the Web does not explicitly reveal its location-relation; rather t...
Conference Paper
Geospatial search for the Web determines the relation of documents' contents to a location within a region. For some pedestrian scenarios, information at a higher granularity down to individual buildings is necessary. In this paper, we describe a process for the extraction and simultaneous verification of precise addresses on German Web pages by a...
Conference Paper
This paper outlines the development and background for a non-intrusive location-based mobile hiking story guide for the Montafon region in Austria. The system comprises different classes of mobile applications and a remote media server, and is designed to be used by a wide userbase of hikers. Our system allows a tourism agency to put up location-ba...
Conference Paper
The Web today is considered to be a sheer unlimited re- source of interlinked information which can be explored fol- lowing links or can be found employing keyword-based search engines. A feature that becomes more and more relevant for our search and use of the Web is the geospatial reference of information. In this paper, we understand the Web as...
Chapter
In recent years, the relation of Web information to a physical location has gained much attention. However, Web content today often carries only an implicit relation to a location. In this chapter, we present a novel location-based search engine that automatically derives spatial context from unstructured Web resources and allows for location-based...