Ändra sökning
Avgränsa sökresultatet
1 - 22 av 22
RefereraExporteraLänk till träfflistan
Permanent länk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Träffar per sida
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sortering
  • Standard (Relevans)
  • Författare A-Ö
  • Författare Ö-A
  • Titel A-Ö
  • Titel Ö-A
  • Publikationstyp A-Ö
  • Publikationstyp Ö-A
  • Äldst först
  • Nyast först
  • Skapad (Äldst först)
  • Skapad (Nyast först)
  • Senast uppdaterad (Äldst först)
  • Senast uppdaterad (Nyast först)
  • Standard (Relevans)
  • Författare A-Ö
  • Författare Ö-A
  • Titel A-Ö
  • Titel Ö-A
  • Publikationstyp A-Ö
  • Publikationstyp Ö-A
  • Äldst först
  • Nyast först
  • Skapad (Äldst först)
  • Skapad (Nyast först)
  • Senast uppdaterad (Äldst först)
  • Senast uppdaterad (Nyast först)
Markera
Maxantalet träffar du kan exportera från sökgränssnittet är 250. Vid större uttag använd dig av utsökningar.
  • 1. Biteus, Jonas
    et al.
    Lindgren, Tony
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för data- och systemvetenskap.
    Planning Flexible Maintenance for Heavy Trucks using Machine Learning Models, Constraint Programming, and Route Optimization2017Ingår i: SAE International Journal of Materials & Manufacturing, ISSN 1946-3979, E-ISSN 1946-3987, Vol. 10, nr 3, 306-315 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Maintenance planning of trucks at Scania have previously been done using static cyclic plans with fixed sets of maintenance tasks, determined by mileage, calendar time, and some data driven physical models. Flexible maintenance have improved the maintenance program with the addition of general data driven expert rules and the ability to move sub-sets of maintenance tasks between maintenance occasions. Meanwhile, successful modelling with machine learning on big data, automatic planning using constraint programming, and route optimization are hinting on the ability to achieve even higher fleet utilization by further improvements of the flexible maintenance. The maintenance program have therefore been partitioned into its smallest parts and formulated as individual constraint rules. The overall goal is to maximize the utilization of a fleet, i.e. maximize the ability to perform transport assignments, with respect to maintenance. A sub-goal is to minimize costs for vehicle break downs and the costs for maintenance actions. The maintenance planner takes as input customer preferences and maintenance task deadlines where the existing expert rule for the component has been replaced by a predictive model. Using machine learning, operational data have been used to train a predictive random forest model that can estimate the probability that a vehicle will have a breakdown given its operational data as input. The route optimization takes predicted vehicle health into consideration when optimizing routes and assignment allocations. The random forest model satisfactory predicts failures, the maintenance planner successfully computes consistent and good maintenance plans, and the route optimizer give optimal routes within tens of seconds of operation time. The model, the maintenance planner, and the route optimizer have been integrated into a demonstrator able to highlight the usability and feasibility of the suggested approach.

  • 2.
    Giannoulis, Constantinos
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för data- och systemvetenskap.
    Kabilan, Vandana
    A Method for VVA Tailoring: The REVVA Generic Process Tailoring Case Study2007Konferensbidrag (Refereegranskat)
  • 3.
    Giannoulis, Constantinos
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för data- och systemvetenskap.
    Svee, Eric-Oluf
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för data- och systemvetenskap.
    Zdravkovic, Jelena
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för data- och systemvetenskap.
    Capturing Consumer Preference in System Requirements Through Business Strategy2013Ingår i: International Journal of Information System Modeling and Design, ISSN 1947-8186, Vol. 4, nr 4, 1-26 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A core concern within Business-IT alignment is coordinating strategic initiatives and plans with Information Systems (IS). Substantial work has been done on linking strategy to requirements for IS development, but it has usually been focused on the core value exchanges offered by the business, and thus overlooking other aspects that influence the implementation of strategy. One of these, consumer preferences, has been proven to influence the successful provisioning of the business's customer value proposition, and this study aims to establish a conceptual link between both strategy and consumer preferences to system requirements. The core contention is that reflecting consumer preferences through business strategy in system requirements allows for the development of aligned systems, and therefore systems that better support a consumer orientation. The contribution of this paper is an approach to establish such alignment, with this being accomplished through the proposal of a consumer preference meta-model mapped to a business strategy meta-model further linked to a system requirements technique. The validity of this proposal is demonstrated through a case study carried out within an institution of higher education in Sweden.

  • 4.
    Giannoulis, Constantinos
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för data- och systemvetenskap.
    Zdravkovic, Jelena
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för data- och systemvetenskap.
    A Design Science Perspective on Business Strategy Modeling2014Ingår i: Enterprise, Business-Process and Information Systems Modeling: 15th International Conference, BPMDS 2014, 19th International Conference, EMMSAD 2014, Held at CAiSE 2014, Thessaloniki, Greece, June 16-17, 2014. Proceedings / [ed] Ilia Bider, Khaled Gaaloul, John Krogstie, Selmin Nurcan, Henderik A. Proper, Rainer Schmidt, Pnina Soffer, Springer Berlin/Heidelberg, 2014, 424-438 s.Konferensbidrag (Refereegranskat)
    Abstract [en]

    An important topic in the modeling for IS development concerns quality of obtained models, especially when these models are to be used in global scopes, or as references. So far, a number of model quality frameworks have been established to assess relevant criteria such as completeness, clarity, modularity, or generality. In this study we take a look at how a research process contributes to the characteristics of a model produced during that process. For example: what should be observed; what research methods should be selected and how should they be applied; what kind of results should be expected; how they should be evaluated, etc. We report a result on this concern by presenting how we applied Design Science Research to model business strategy.

  • 5.
    Jalali, Amin
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för data- och systemvetenskap.
    Aspect-Oriented Business Process Management2016Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Att separera angelägenheter har länge ansetts som en effektiv och ändamålsenlig strategi för att hantera komplexitet i informationssystem. Sådana angelägenheter, till exempel säkerhet och enskildhet, kan skära tvärs över andra angelägenheter i ett system, och de kallas därför övergripande angelägenheter. Hanteringen av dessa kan vara utspridda genom hela systemet, vilket ökar komplexiteten.

    Aspektorientering är ett paradigm som syftar till att modularisera övergripande angelägenheter. Detta paradigm är väl utforskat i programvaruområdet, där många aspektorienterade programmeringsspråk utvecklats. Paradigmet har också undersökts i andra områden som kravhantering och tjänstesammansättning. I ärendehanteringsområdet (BPM) syftar aspektorienterad processmodellering till att inkapsla övergripande angelägenheter i processmodeller. Det är dock inte klart hur dessa modeller bör stödjas i hela ärendehanteringslivscykeln. Dessutom är existerande stöd för att utforma dessa modeller begränsat till tvingande processmodeller som enbart stödjer rigida affärsprocesser. Det har inte heller undersökts hur denna modulariseringsteknik kan stödjas genom deklarativa eller hybridmodeller för att hantera separation av övergripande angelägenheter för flexibla affärsprocesser.

    Därför undersöker denna avhandling hur aspektorientering kan stödjas i hela ärendehanteringslivscykeln med hjälp av tvingande aspektorienterade affärsprocessmodeller. Den undersöker också hur deklarativa och hybridaspektorienterade affärsprocessmodeller kan stödja separation av övergripande angelägenheter i BPM-området. Avhandlingens resultat bygger på designvetenskaplig forskning, och de presenteras som en uppsättning av artefakter (i form av konstruktioner, modeller, metoder och instansieringar) och som empiriska iakttagelser.

    De framtagna artefakterna stödjer modellering, analys, genomförande, konfiguration, övervakning och modifiering av övergripande angelägenheter i affärsprocesser. Artefakterna erbjuder stöd för hantering av dessa angelägeheter för hela ärendehanteringslivscykeln. Användningen av dessa artefakter och deras tillämpningar visar att de kan minska komplexiteten i processmodeller genom att separera övergripande angelägenheter.

  • 6.
    Jalali, Amin
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för data- och systemvetenskap.
    Foundation of Aspect Oriented Business Process Management2012Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Reducing the complexity in information systems is a main concern on which researchers work. Separation of concerns, also known as the principle of ‘divide and conquer’, has long time been a strategy for dealing with complexity. Two examples of the application of this principle in the area of information system design are the break out the data management into Database Management Systems(DBMSs) and the separation of the business logic from the application logic into Business Process Management Systems (BPMSs). However, separation of cross-cutting concerns from the core-concern of a business process is not yet supported in the Business Process Management (BPM) area. Aspect Oriented principle recommends such a separation. When looking into the business process, several concerns, such as security and privacy, can be identified. Therefore, a formal model that provides a foundation for enabling BPMSs to support separation of concerns in BPM area is needed. This thesis provides a formal model for dealing with separation of concerns in the BPM area. Implementing this model in BPMSs would facilitate the design and implementation of business processes with a lower level of complexity, which in turn would reduce the costs associated with BPM projects. The thesis starts with a literature review on aspect orientation both in programming and in the BPM areas. Based on this study, a list of requirements for an Aspect Oriented Service for BPMSs is compiled. Then a formal model for such a service, fulfilling a set of these requirements, is designed using Coloured Petri Nets and implemented in CPN Tools. The model is evaluated through the execution of a number of scenarios. The solution is also validated through an industrial case study. The results of the case study are presented the direction for future work outlined. The case study demonstrates that separation of concerns through aspect orientation does indeed reduce the complexity of business process models.

  • 7.
    Jalali, Amin
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för data- och systemvetenskap.
    Service Oriented Modularization using Coloured Petri Nets2012Konferensbidrag (Övrig (populärvetenskap, debatt, mm))
    Abstract [en]

    Modelling service oriented systems using Coloured Petri Nets usually results in cluttered nets which are hard to understand and modify. This complexity is a result of many interactions among services. This paper presents a method for designing service oriented models using coloured petri nets.This method results us in less complex nets which could be extended easier.The validation of the method is given through demonstrating its impact on defining operational semantics of a service.

  • 8.
    Jalali, Amin
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för data- och systemvetenskap.
    Supporting Enactment of Aspect Oriented Business Process Models: an approach to separate cross-cutting concerns in action2013Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Coping with complexity in Information Systems and Software Engineering is an important issue in both research and industry. One strategy to deal with this complexity is through a separation of concerns, which can result in reducing the complexity, improving the re-usability, and simplifying the evolution.Separation of concerns can be addressed through the Aspect Oriented paradigm. Although this paradigm has been well researched in the field of programming, it is still in a preliminary stage in the area of Business Process Management. While some efforts have been made to propose aspect orientation for business process modeling, it has not yet been investigated how these models should be implemented, configured, run, and adjusted.Such a gap has restrained the enactment of aspect orientated business process models in practice.Therefore, this research enables the enactment of such models to support the separation of cross-cutting concerns in the entire business process management life-cycle.It starts by defining the operational semantics for the Aspect Oriented extension of the Business Process Model and Notation.The semantics specifies how such models can be implemented and configured, which can be used as a blueprint to support the enactment of aspect oriented business process models.The semantics is implemented in the form of artifacts, which are then used in a banking case study to investigate the current modeling technique.This investigation revealed new requirements, which should be considered in aspect oriented modeling approaches.Thus, the current modeling notation has been extended to include new requirements.The extended notation has been formalized, and investigated through re-modeling the processes in the case study. The results from this investigation show the need to refine the separation rules to support the encapsulation of aspects based on different business process perspectives. Therefore, the new refinement is proposed, formalized, and implemented.The implementation is then used as a prototype to evaluate the result through a case study.

  • 9.
    Juell-Skielse, Gustaf
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för data- och systemvetenskap.
    Improving Organizational Effectiveness through Standard Application Packages and IT Services2011Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Today, the design, use and distribution of standard application packages are changing due to the emergence of service orientation. In the private sector, Enterprise Resource Planning (ERP) systems are extended to include IT services. In the public sector, standard application packages are integrated with IT services which are often referred to as e-Government. E-Government can be extended with mobile technology to add mobility to public processes, so called m-Government.

    The problem addressed in this thesis is how to improve organizational effectiveness through the use of standard application packages and IT services. The objectives are to:

    • ­Develop a model for explaining the level of adoption of extended ERP among small and medium sized companies.  
    • ­Identify implications and design patterns of business models for service oriented ERP.
    • ­Establish principles for the design of local government m-services.
    • ­Develop a method for benefits evaluation of information systems with integrated services.

    The thesis contributes with theory for analyzing, explaining and predicting how the use of standard application packages as well as IT services affects organizational effectiveness. To practice, it provides new concepts that can change the perceptions and mental models that IS-professionals, such as management consultants, use in their professional lives. In particular, it provides implications, design principles, a model and a method for the use of services in conjunction with standard application packages in public and private sector organizations.

    For future research it is suggested to investigate how service orientation affects implementation methods for standard application packages and to investigate the requirements of completely integrated e-Government on e-services, business models and back-office systems.

  • 10.
    Juell-Skielse, Gustaf
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för data- och systemvetenskap.
    Enquist, Håkan
    School of Business, Economics and Law, University of Gothenburg.
    Implications of ERP as Service2011Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper we present implications for using and delivering Enterprise Resource Planning as services (ERP-as-a-service). The objective is to construct a framework of opportunities and challenges for users and suppliers of ERP-as-a-service. The framework is based on a combination of literature study and field study and includes approximately 80 implications. New implications, not found in literature, were identified in the field study. Examples of new implications include: more focus on IT-value; simplified phasing of implementation and improved supplier brand. For future research it is suggested that the framework is tested in a larger setting and that implications are prioritized for certain industries and types of business models.

  • 11.
    Juell-Skielse, Gustaf
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för data- och systemvetenskap.
    Perjons, Erik
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för data- och systemvetenskap.
    VAMEE: A Value Aware Method for Evaluating Inclusive E-Government Initiatives2011Ingår i: The Practice of Enterprise Modeling / [ed] Johannesson, P., Krogstie, J., Opdahl, A., Heidelberg: Springer , 2011, 97-111 s.Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    The growing use of ICT solutions for improving the public sector has created a need for valuating e-government initiatives. A number of methods for this purpose have been developed, but they are typically restricted to analyzing the benefits and costs of only one single actor. There is, therefore, a need for methods that take a broader view and take into account entire networks of actors. This paper proposes a novel method, called VAMEE, the purpose of which is to produce a well-grounded and easily understandable valuation of an e-government initiative that takes into consideration the benefits, costs, and interrelationships of all actors concerned. The basis of the proposed method is a combination of enterprise modeling techniques, in particular goal modeling and value modeling, with an established method for cost benefit analysis (i.e. Peng). VAMEE is designed to be inclusive, easily understandable, and visual. These properties of the method will support accurate and unbiased valuations as well as improved innovation in the development of e-government initiatives.

  • 12.
    Kajko-Mattsson, Mira
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för data- och systemvetenskap.
    Upfront corrective maintenance at the front-end support level2005Ingår i: Managing corporate information systems evolution and maintenance / [ed] Khaled M. Khan, Yan Zhang, Hershey, PA: Idea Group Publishing, 2005, 75-107 s.Kapitel i bok, del av antologi (Övrigt vetenskapligt)
    Abstract [en]

    This chapter presents the process of upfront corrective maintenance at the front-end support level. The chapter is logically divided into two parts. The first part introduces the domain of the upfront corrective maintenance process, and presents its current status practiced in the industry. It first describes the process, places it within a global virtual IT enterprise and explains its role within the enterprise. It then puts the process in the context of a total front-end support process, the process performing a multitude of diverse types of support activities. Finally, it lists the problems encountered by the front-support organisations today. The second part provides a glimpse into Corrective Maintenance Maturity Model (CM3): Upfront Maintenance, a process model specialized in upfront corrective maintenance. It describes its process phases, maturity levels, and collaboration with the CM3: Problem Management model, a problem management process model at the back-end support level. The goal of this chapter is to provide a detailed insight of the process of upfront corrective maintenance.

  • 13.
    Karokola, Geoffrey Rwezaura
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för data- och systemvetenskap.
    A Framework for Securing e-Government Services: The Case of Tanzania2012Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    e-Government services are becoming one of the most important and efficient means by which governments (G) interact with businesses (B) and citizens (C). This has brought not only tremendous opportunities but also serious security challenges. Critical information assets are exposed to current and emerging security risks and threats. In the course of this study, it was learnt that e-government services are heavily guided and benchmarked by e-Government maturity models (eGMMs). However, the models lack built-in security services, technical as well as non-technical; leading to lack of strategic objectives alignment between e-government services and security services. Information security has an important role in mitigating security risks and threats posed to e-government services. Security improves quality of the services offered.

    In light of the above, the goal of this research work is to propose a framework that would facilitate government organisations to effectively offer appropriate secure e-government services. To achieve this goal, an empirical investigation was conducted in Tanzania involving six government organizations. The investigations were inter-foiled by a sequence of structural compositions resulting in a proposition of a framework for securing e-government services which integrates IT security services into eGMMs. The research work was mainly guided by a design science research approach complemented in parts by systemic-holistic and socio-technical approaches.

    The thesis contributes to the empirical and theoretical body of knowledge within the computer and systems sciences on securing e-government structures. It encompasses a new approach to secure e-government services incorporating security services into eGMMs. Also, it enhances the awareness, need and importance of security services to be an integral part of eGMMs to different groups such as researched organizations, academia, practitioners, policy and decision makers, stakeholders, and the community.

  • 14.
    Lansner, Anders
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Numerisk analys och datalogi (NADA). Royal Institute of Technology, Sweden.
    Benjaminsson, Simon
    Nexa: A scalable neural simulator with integrated analysis2012Ingår i: Network: Computation in Neural Systems, ISSN 0954-898X, Vol. 23, nr 4, 254-271 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Large-scale neural simulations encompass challenges in simulator design, data handling and understanding of simulation output. As the computational power of supercomputers and the size of network models increase, these challenges become even more pronounced. Here we introduce the experimental scalable neural simulator Nexa, for parallel simulation of large-scale neural network models at a high level of biological abstraction and for exploration of the simulation methods involved. It includes firing-rate models and capabilities to build networks using machine learning inspired methods for e.g. self-organization of network architecture and for structural plasticity. We show scalability up to the size of the largest machines currently available for a number of model scenarios. We further demonstrate simulator integration with online analysis and real-time visualization as scalable solutions for the data handling challenges.

  • 15.
    Nyfjord, Jaana
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för data- och systemvetenskap.
    Kajko-Mattsson, Mira
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för data- och systemvetenskap.
    Integrating risk management with software development: state of practice2008Ingår i: Proceedings of The International MultiConference of Engineers and Computer Scientists 2008 Vol. I / [ed] S. I. Ao, Oscar Castillo, Craig Douglas, David Dagan Feng, Jeong-A Lee, Newswood Limited , 2008, 878-884 s.Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    In this paper, we investigate the state of practice of integrating risk management with software development in 37 software organizations. We do this by using a set of evaluation criteria covering various process integration aspects. Our results recognize that process integration in this domain is still in its infancy. There is a great need for process integration and process integration models within the industry studied.

  • 16.
    Nyfjord, Jaana
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för data- och systemvetenskap.
    Kajko-Mattsson, Mira
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för data- och systemvetenskap.
    Software risk management: practice contra standard models2008Ingår i: PROCEEDINGS OF THE SECOND INTERNATIONAL CONFERENCE ON RESEARCH CHALLENGES IN INFORMATION SCIENCE RCIS 2008 Marrakech, June 3-6, Morocco / [ed] Colette Rolland, Martine Collard, Oscar Pastor, André Flory, Jean Louis Cavarero, IEEE Computer Society Press , 2008, 65-70 s.Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Little is known about the compliance of risk management models with the industrial practice and vice versa. In this paper, we compare the industrial risk management practice against a risk management model that we have synthesized from a set of current risk management models. This comparison has resulted in several discrepancies observed. As a result, this paper suggests a list of issues that need to be addressed in both the industrial and standard models.

  • 17.
    Rahman, Hasibur
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för data- och systemvetenskap.
    Self-Organizing Logical-Clustering Topology for Managing Distributed Context Information2015Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Internet of Things (IoT) is on the verge of experiencing a paradigm shift, the focus of which is the integration of people, services, context information, and things in the Connected Society, thus enabling Internet of Everything (IoE). Hundreds of billions of things will be connected to IoT/IoE by 2020. This massive immersion of things paves the way for sensing and analysing anything, anytime and anywhere. This everywhere computing coupled with Internet or web-enabled services have allowed access to a vast amount of distributed context information from heterogeneous sources. This enormous amount of context information will remain under-utilized if not properly managed. Therefore, this thesis proposes a new approach of logical-clustering as opposed to physical clustering aimed at enabling efficient context information management.

    However, applying this new approach requires many research challenges to be met. By adhering to a design science research method, this thesis addresses these challenges and proposes solutions to them. The thesis first outlines the architecture for realizing logical-clustering topology for which a two-tier hierarchical-distributed hash table (DHT) based system architecture and a Software Defined Networking (SDN)-like approach are utilized whereby the clustering identifications are managed on the top-level overlay (as context storage) and heterogeneous context information sources are controlled via the bottom level. The feasibility of the architecture has been proven with an ns-3 simulation tool. The next challenge is to enable scalable clustering identification dissemination, for which a distributed Publish/Subscribe (PubSub) model is developed. The massive number of immersed nodes further necessitates a dynamic self-organized system. The thesis concludes by proposing new algorithms with regard to autonomic management of IoT to bring about the self-organization. These algorithms enable to structure the logical-clustering topology in an organized way with minimal intervention from outside sources and further ensure that it evolves correctly. A distributed IoT context information-sharing platform, MediaSense, is employed and extended to prove the feasibility of the dynamic PubSub model and the correctness of self-organized algorithms and to utilize them as context storage. Promising results have provided a high number of PubSub messages per second and fast subscription matching. Self-organization further enabled logical-clustering to evolve correctly and provided results on a par with the existing MediaSense for entity joining and high discovery rates for non-concurrent entity joining.

    The increase in context information requires its proper management. Being able to cluster (i.e. filter) heterogeneous context information based on context similarity can help to avoid under-utilization of resources. This thesis presents an accumulation of work which can be comprehended as a step towards realizing the vision of logical-clustering topology.

  • 18.
    Sotomane, Constantino
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för data- och systemvetenskap.
    Factors affecting the use of data mining in Mozambique: Towards a framework to facilitate the use of data mining2014Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Advances in technology have enabled organizations to collect a variety ofdata at high speed and provided the capacity to store them. As a result theamount of data available is increasing daily at a rapid rate. The data stored inorganizations hold important information to improve decision making andgain competitive advantage. To extract useful information from these hugeamounts of data, special techniques such as data mining are required. Datamining is a technique capable of extracting useful knowledge from vastamounts of data. The successful application of data mining in organizationsdepends on several factors that may vary in relation to the environment. InMozambique, these factors have never been studied. The study of the factorsaffecting the use of data mining is important to determine which aspectsrequire special attention for the success of the application of data mining.This thesis presents a study of the level of awareness and use of datamining in Mozambique and the factors affecting its use. It is a step towardsthe development of a framework to facilitate the application of data miningin Mozambique. The study is exploratory and uses multiple case studies intwo institutions in Maputo city, the capital of Mozambique, one in the areaof agriculture and the other in the field of electricity, and of Maputo citymore broadly. The study involved a combination of observations, focusgroup discussions and enquiries directed at managers and practitioners onaspects of information technology (IT) and data analysis. The results of the study reveal that the level of awareness and use of datamining in Mozambique is still very weak. Only a limited number ofprofessionals in IT are aware of the concept or its uses. The main factorsaffecting the use of data mining in Mozambique are: the quality, availabilityand integration of, access to data, skill in data mining, functional integration,alignment of IT and business, interdisciplinary learning, existence ofchampions, commitment of top management, existence of changemanagement, privacy, cost and the availability of technology. Threeapplications were developed in two real settings, which showed that thereare problems to be solved with data mining. The two examples in the area ofelectricity demonstrate how data mining is used to develop models toforecast electricity consumption and how they can enhance the estimation ofelectricity to be sold to the international market. The application in the areaof agriculture extracts associations between the characteristics of smallfarmers and the yield of maize from a socioeconomic database with hundreds of attributes. The applications provide practical examples of howdata mining can help to discover patterns that can lead to the development ofmore accurate models and find interesting associations between variables inthe dataset. The factors identified in this thesis can be used to determine thefeasibility of the implementation of data mining projects and ensure itssuccess.

  • 19.
    Sundholm, Hillevi
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för data- och systemvetenskap.
    Artman, Henrik
    Ramberg, Robert
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för data- och systemvetenskap.
    Backdoor creativity: collaborative creativity in technology supported teams2004Ingår i: Cooperative systems design: senario-based design of collaborative systems / [ed] Francoise Darses, Rose Dieng, Carla Simone, Manuel Zacklad, Amsterdam: IOS Press, 2004, 99-114 s.Konferensbidrag (Refereegranskat)
  • 20.
    Verhagen, Harko
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för data- och systemvetenskap.
    Autonomy and reasoning for natural and artificial agents2004Ingår i: Agents and computational autonomy: potential, risks, and solutions / [ed] Matthias Nickles, Michael Rovatsos, Gerhard Weiss, Berlin: Springer Berlin/Heidelberg, 2004, Vol. 2969 , 83-94 s.Konferensbidrag (Övrigt vetenskapligt)
  • 21.
    Wu, Desheng D.
    et al.
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Företagsekonomiska institutionen. University of Toronto, Canada.
    Olson, David L.
    Luo, Cuicui
    A Decision Support Approach for Accounts Receivable Risk Management2014Ingår i: IEEE Transactions on Systems, Man, and Cybernetics: Systems, ISSN 2168-2216, Vol. 44, nr 12, 1624-1632 s.Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Financial disasters in private firms led to increased emphasis on various forms of risk management, to include market risk management, operational risk management, and credit risk management. Financial institutions are motivated by the need to meet increased regulatory requirements for risk measurement and capital reserves. This paper describes and demonstrates a model to support risk management of accounts receivable. We present a decision support model for a large bank enabling assessment of risk of default on the part of loan recipients. A credit scoring model is presented to assess account creditworthiness. Alternative methods of risk measurement for fault detection are compared, and a logistic regression model selected to analyze accounts receivable risk. Accuracy results of this model are presented, enabling accounts receivable managers to confidently apply statistical analysis through data mining to manage their risk.

  • 22.
    Xiao, Bin
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Institutionen för data- och systemvetenskap.
    Data-Centric Network of Things: A Method for Exploiting the Massive Amount of Heterogeneous Data of Internet of Things in Support of Services2017Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Internet of things (IoT) generates massive amount of heterogeneous data, which should be efficiently utilized to support services in different domains. Specifically, data need to be supplied to services by understanding the needs of services and by understanding the environment changes, so that necessary data can be provided efficiently but without overfeeding. However, it is still very difficult for IoT to fulfill such data supply with only the existing supports of communication, network, and infrastructure; while the most essential issues are still unaddressed, namely the heterogeneity issue, the recourse coordination issue, and the environments’ dynamicity issue. Thus, this necessitates to specifically study on those issues and to propose a method to utilize the massive amount of heterogeneous data to support services in different domains.

    This dissertation presents a novel method, called the data-centric network of things (DNT), which handles heterogeneity, coordinates resources, and understands the changing IoT entity relations in dynamic environments to supply data in support of services. As results, various services based on IoT (e.g., smart cities, smart transport, smart healthcare, smart homes, etc.) are supported by receiving enough necessary data without overfeeding.

    The contributions of the DNT to IoT and big data research are: firstly the DNT enables IoT to perceive data, resources, and the relations among IoT entities in dynamic environments. This perceptibility enhances IoT to handle the heterogeneity in different levels. Secondly, the DNT coordinates IoT edge resources to process and disseminate data based on the perceived results. This releases the big data pressure caused by centralized analytics to certain degrees. Thirdly, the DNT manages entity relations for data supply by handling the environment dynamicity. Finally, the DNT supply necessary data to satisfy different service needs, by avoiding either data-hungry or data-overfed status.

1 - 22 av 22
RefereraExporteraLänk till träfflistan
Permanent länk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf