| 1. |
- Fernstad, Sara Johansson, et al.
(författare)
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To Explore What Isnt There-Glyph-Based Visualization for Analysis of Missing Values
- 2022
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Ingår i: IEEE Transactions on Visualization and Computer Graphics. - : IEEE COMPUTER SOC. - 1077-2626 .- 1941-0506. ; 28:10, s. 3513-3529
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Tidskriftsartikel (refereegranskat)abstract
- This article contributes a novel visualization method, Missingness Glyph, for analysis and exploration of missing values in data. Missing values are a common challenge in most data generating domains and may cause a range of analysis issues. Missingness in data may indicate potential problems in data collection and pre-processing, or highlight important data characteristics. While the development and improvement of statistical methods for dealing with missing data is a research area in its own right, mainly focussing on replacing missing values with estimated values, considerably less focus has been put on visualization of missing values. Nonetheless, visualization and explorative analysis has great potential to support understanding of missingness in data, and to enable gaining of novel insights into patterns of missingness in a way that statistical methods are unable to. The Missingness Glyph supports identification of relevant missingness patterns in data, and is evaluated and compared to two other visualization methods in context of the missingness patterns. The results are promising and confirms that the Missingness Glyph in several cases perform better than the alternative visualization methods.
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| 2. |
- Jalilzadehazhari, Elaheh, 1985-
(författare)
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A decision-making framework for enhancing client well-being : When designing windows and blinds
- 2019
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The current state of window and blind design moves beyond evaluating a single function, such as energy consumption, to include a human perspective in architectural design approach to create value. A current thought among architects and design professionals is that the highest value outcomes can be obtained when any architectural design contributes to enhanced well-being. Previous studies show that an individual’s well-being is determined by five main life domain factors: health, economy, personality, demographic variables and behavior variables. However, the life domain factors health and economy show stronger and more positive correlations to well-being. At this point, value creation within architectural design context, including window and blind design, can be seen as an attempt to enhance well-being by improving health and providing economic benefits for clients. Clients can represent i) owners who own a built asset, ii) investors who commit capital and expect to obtain financial return, or iii) occupants who live or work in the building every day. In the context of owner-occupied buildings, the value creation process is mainly seen as an attempt to enhance well-being for one entity by improving health and providing economic benefits. When considering investment properties or assets held for sale, the value creation process is mainly translated into an attempt to enhance well-being for several entities by improving health for occupants and providing economic benefits for owners and/or investors.Selecting a window and blind design to enhance client well-being remains a challenging task due to three main difficulties. The first difficulty relates to the contradictory effects of windows and blinds on visual and thermal comfort, energy consumption and life cycle cost. The second difficulty is the availability of a variety of window and blind designs in different sizes, positions and forms, making the selection of windows and blinds an intricate decision challenge for architects and designers. The third difficulty involves decisions about the selection of windows and blinds that should include all criteria and their interactions simultaneously.To resolve the abovementioned difficulties, this research applied the analytical hierarchy process (AHP) as a multi-criteria decision-making method to select a window and blind design based on a trade-off between visual comfort, thermal comfort, energy consumption and life cycle cost. The analyses of results show the capability of AHP in resolving difficulties, however its application is mainly limited to a small number of designs. To overcome this limitation, a decision-making framework was developed based on integration between non-dominated sorting genetic algorithm-II (NSGA-II) as an optimization algorithm and AHP. The strength and limitations of the decision-making framework were later tested by employing it in window and blind design practice. To investigate further benefits from the implementation of the framework, it was expanded by evaluating additional building envelopes, i.e. windows as well as external walls, roof and floor constructions, which made it possible to select a trade-off construction solution. The analyses of results show the framework’s ability to resolve difficulties and locate a trade-off design in a relatively short period of time. However, the decision-making framework only allows the analysis of the objective criteria for evaluating visual comfort, thermal comfort, energy consumption and life cycle cost. This is because it is necessary to rely on the creativity of the architects and designers when designing windows and blinds in order to consider subjective issues. The decision-making framework can be used either by design teams or customer service experts in window manufacturing companies. A literature study was therefore conducted to extend the technology acceptance model and thereby investigate the determinants of framework user acceptance of the decision-making framework. The results showed that organizational, individual, technological and environmental characteristics were the most influential external variables when investigating determinants of framework user acceptance of the framework. Organizational characteristics included top management support, training, organizational culture, and organizational size, while individual characteristics included the users’ previous knowledge and experience. Technological characteristics embraced information quality and system quality, meanwhile environmental characteristics comprised fulfillment of regulations and competitiveness.
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| 3. |
- Jalilzadehazhari, Elaheh, 1985-, et al.
(författare)
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Application of analytical hierarchy process for selecting an interior window blind
- 2017
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Ingår i: Architectural Engineering and Design Management. - : Taylor & Francis. - 1745-2007 .- 1752-7589. ; 13:4, s. 308-324
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Tidskriftsartikel (refereegranskat)abstract
- Window blinds have a substantial role in shaping the energy consumption and improving thermal comfort and visual comfort. However, difficulties in selecting a window blind remain, due to existence of potential conflicts between visual, thermal, energy and life cycle cost. To overcome this problem, this study evaluates the performance of interior blinds, including venetian with slat of 0° and 45°, roller and double pleated blinds with respect to visual, thermal, energy and life cycle cost. Later, the Analytical hierarchy method (AHP) is used for selecting the best blind based on trade-off among the visual, thermal, energy and life cycle cost. In using AHP, visual comfort is determined as most important objective with a weight of 52%. The results show that venetian blind with slat of 0° drawn 100% is the trade-off blind. Accomplishing the sensitivity analysis on blinds’ global weight shows that venetian blind with slat of 0° drawn 100% remains the trade-off blind until the weight of energy and life cycle cost is below 37% and 57% respectively and the weight of visual comfort is above 4%. However, changing thermal comfort weight has no impact on ranking of the blinds. This study shows the capability of AHP in managing the conflicts.
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| 4. |
- Jalilzadehazhari, Elaheh, 1985-, et al.
(författare)
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Application of multi-objective optimization for resolving conflicts when selecting windows
- 2019
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Ingår i: The 9<sup>th</sup> International Conference on Sustainable Development in the Building and Environment（SuDBE2019）& the International Forum of Green and Healthy Buildings.. - Reading and Cambridge, UK.
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Konferensbidrag (refereegranskat)abstract
- Sweden passed legislation to achieve a target of net zero greenhouse gas emissions by the end of 2045. The Energy Performance of Building Directive further obliged European countries to ensure zero-energy building codes and improve the quality of indoor environments when buildings are renovated, as approximately 40% of total greenhouse gas emissions in Sweden are produced while heating buildings. Windows currently play a significant role in improving the quality of indoor environments and cutting total energy consumption, thereby reducing greenhouse gas emissions and mitigating environmental impact. Selecting a suitable window design is a complicated task compounded by two main difficulties: i) the availability of multiple window designs, each with a different glazing system, size, form and position; and ii) conflict between visual comfort, thermal comfort and energy consumption. Previous studies have primarily analysed a limited selection of window designs; however, analysing a wide variety of glazing systems, sizes, forms and positions will help resolve the abovementioned difficulties, thereby ensuring zero-energy building codes while improving the quality of an indoor environment. A multi-objective optimization was therefore completed to analyse the performance of a wide variety of window design variables and select suitable designs for an office room in Sweden. The results show the potential of multi-objective optimisation to resolve the difficulties of selecting suitable window designs.
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| 5. |
- Jalilzadehazhari, Elaheh, 1985-, et al.
(författare)
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Determinants of users’ acceptance of a computer-based system
- 2019
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Ingår i: 36th CIB W78 2019 Conference ICT in Design, Construction and Management in Architecture, Engineering, Construction and Operations (AECO), 18-20 September, 2019. - Newcastle, United Kingdom : University of Northumbria.
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Konferensbidrag (refereegranskat)abstract
- Sweden has an ambitious target to attain 50% more efficient energy use by 2030. Improving the energy performance of buildings provides a great opportunity to achieve the above-mentioned target. At this point, windows play a substantial role in improving indoor environmental quality and reducing energy consumption and cost. A computer-based system was therefore developed, which allows selecting a suitable window design. The computer-based system was intended to be used in a large-sized window and door manufacturing company in Sweden. However, the benefits of implementing the computer-based system cannot be realized until users accept using it. Former literature employed the technology acceptance model to investigate the influence of external variables on cognitive beliefs and trace their effects on users’ intention and actual system use. A successful application of TAM relies on the specification of the external variable. Accordingly, this paper conducted a systematic literature review to determine the external variable, affecting users' acceptance, thereby extended TAM. The analyses of results showed that organizational, individual, technological and environmental characteristics were the most influential external variables when investigating determinants of users' acceptance toward a computer-based system. Organizational characteristics contained mainly top management support, training, organizational culture, and organizational size, while individual characteristics embraced users’ previous knowledge and experience. Technological characteristics comprised information quality and system quality, meanwhile environmental characteristics included fulfillment of regulations and competitiveness. The extended TAM overcomes limitations attributed to the unified theory of acceptance and use of technology model since it considers attitude as direct determinants of intentions. In addition, the extended TAM is advantageous when compared with technology, organization, environment framework, because it has clear constructs, which allows tracing the influence of external variables on cognitive beliefs, and thereby their effects on users’ intention and actual system use. The extended TAM will be used to investigate determinants of users’ acceptance of the computer-based system in the manufacturing company in Sweden and compare the effect of external variables on users' acceptance.
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| 6. |
- Jalilzadehazhari, Elaheh, 1985-, et al.
(författare)
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Developing a decision-making framework for resolving conflicts when selecting windows and blinds
- 2019
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Ingår i: Architectural Engineering and Design Management. - : Taylor & Francis. - 1745-2007 .- 1752-7589. ; 15:5, s. 357-381
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Tidskriftsartikel (refereegranskat)abstract
- Windows and blinds play a significant role in both shaping energy consumption and enhancing indoor comfort. But there are still difficulties with selecting windows and blinds due to the existence of potential conflicts between visual comfort, thermal comfort, energy consumption and life-cycle cost. A literature review was conducted with the purpose of developing a decision-making framework that resolves the conflicts, and allows selecting a window and blind design based on trade-off between visual comfort, thermal comfort, energy consumption and life-cycle cost. The decision-making framework was developed by integrating non-dominated sorting genetic algorithm-II as an optimization algorithm with analytical hierarchy process as a multi-criteria decision-making method. The optimization algorithm considers different window and blind design variables and analyses multiple designs, while the multi-criteria decision-making method ranks the optimization results and selects a trade-off design. An operating package enabled the decision-making framework to be automated. The operating package was obtained by coupling EnergyPlus as a simulation tool and modeFRONTIER as an integration platform. The decision-making framework was developed to select a trade-off window and blind design through intelligent use of simulation in analysing big-data in built environment, energy and cost sectors. Application of the framework ensures the minimum visual and thermal comfort thresholds with the lowest energy demand and cost. Architects and designers can use the framework during the design or renovation phase of residential and commercial buildings.
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| 7. |
- Jalilzadehazhari, Elaheh, 1985-
(författare)
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Windows and blinds selection for enhancing subjective well-being
- 2017
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Earlier studies in the context of windows and blinds selection have mostly tried to increase the awareness regarding various effects of windows and blinds selection on subjective well-being, including their effect on visual comfort, thermal comfort, energy consumption and life cycle cost. However, the main problem is the potential conflicts between visual comfort, thermal comfort, energy consumption and life cycle cost. Increased awareness about the contradictory effect of windows and blinds selection on subjective well-being on one hand and lack of a feasible method in managing the conflicts on the other hand may bind individuals, as decision-makers, in a situation where they follow the immediate economic benefits rather than the long-term visual and thermal benefits. To solve the mentioned problem, this study analysed first the degree of the conflicts between average daylight illuminance and total energy consumption in Sweden. This decision was made due to large variation in solar elevation angle and solar intensity between summer and winter in Sweden, which has significant effects on daylight illuminance and total energy consumption. Analysing the conflicts was accomplished by developing two multivariate linear regression models for calculating average daylight illuminance and total energy consumption. Comparison and analysis of the multivariate linear regression models showed the existence of a high degree of conflicts, which makes window and blind selection a rather complex multidimensional problem. Specifying the degree of the conflicts formed a hypothesis as: “A multi criteria decision-making method increases the controllability and manages the conflicts in selecting windows and blinds”. The developed hypothesis was later tested by employing analytical hierarchy process, as widely used multi criteria decisionmaking method. The analytical hierarchy process prioritizes decision-maker’ preferences and introduces a desired trade-off solution. The results of employing analytical hierarchy process showed the capability of it in managing the conflicts among visual comfort, thermal comfort, energy consumption and life cycle cost. Finally, the application of the analytical hierarchy process was expanded by integrating it with nondominated sorting genetic algorithm-II, as an optimization algorithm. Through this integration, optimization algorithm combines windows’ and blinds’ design variables and analyses a large number of solutions, while analytical hierarchy process ranks the solutions based on decision-makers’ preferences and introduces a desired trade-off solution. The integration between analytical hierarchy process and the nondominated sorting genetic algorithm-II was presented later as a conceptual framework. The developed conceptual framework can be used for selecting windows and blinds II in both residential and commercial buildings. In selecting windows and blinds, the conceptual framework is a novel solution to the lack of a feasible method for increasing the controllability for decision-makers and obtaining a desired trade-off solution.
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| 8. |
- Jern, Mikael, 1946-, et al.
(författare)
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The GAV Toolkit for Multiple Linked Views
- 2007
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Ingår i: Fifth International Conference on Coordinated and Multiple Views in Exploratory Visualization, 2007. CMV '07.. - Los Alamitos, CA, USA : IEEE Computer Society. - 0769529038 ; , s. 85-97
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Konferensbidrag (refereegranskat)abstract
- Implementing InfoVis multivariate data tools, timelinked coordinated views and visual dynamic queries with conditioning from scratch is not a simple programming task. Our research objective is to develop a generic GeoAnalytics visualization (GAV) component toolkit, based on the principles behind visual analytics (VA), for dynamically exploring time-varying, geographically referenced and multivariate attributes simultaneously. GAV includes components based on a synergy of technologies from information visualization, geovisualization and scientific visualization. Our research concentrates on improving visual user interfaces (VUI) methods and trying to extend existing visual representation techniques. The effectiveness of our proposed component toolkit and framework is demonstrated in two customized applications GeoWizard analysing multivariate energy usage data for Swedish municipalities and MD-Explorer exploring multivariate data using novel interactive ternary diagrams. We use parallel coordinates with embedded visual inquiry methods that serves as a visual control panel for dynamically linked and coordinated views. Finally, discoveries made during the visual exploration process can be captured and organized in a format for later recall and communication to others.
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| 9. |
- Johansson Fernstad, Sara, et al.
(författare)
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A Task Based Performance Evaluation of Visualization Approaches for Categorical Data Analysis.
- 2011
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Ingår i: Proceedings - 15th International Conferenceon Information Visualisation. - Los Alamitos, CA, USA : IEEE Computer Society. - 9781457708688 ; , s. 80-89
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Categorical data is common within many areas and efficient methods for analysis are needed. It is, however, often difficult to analyse categorical data since no general measure of similarity exists. One approach is to represent the categories with numerical values (quantification) prior to visualization using methods for numerical data. Another is to use visual representations specifically designed for categorical data. Although commonly used, very little guidance is available as to which method may be most useful for different analysis tasks. This paper presents an evaluation comparing the performance of employing quantification prior to visualization and visualization using a method designed for categorical data. It also provides a guidance as to which visualization approach is most useful in the context of two basic data analysis tasks: one related to similarity structures and one related to category frequency. The results strongly indicate that the quantification approach is most efficient for the similarity related task, whereas the visual representation designed for categorical data is most efficient for the task related to category frequency.
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| 10. |
- Johansson Fernstad, Sara, 1980-
(författare)
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Algorithmically Guided Information Visualization : Explorative Approaches for High Dimensional, Mixed and Categorical Data
- 2011
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Facilitated by the technological advances of the last decades, increasing amounts of complex data are being collected within fields such as biology, chemistry and social sciences. The major challenge today is not to gather data, but to extract useful information and gain insights from it. Information visualization provides methods for visual analysis of complex data but, as the amounts of gathered data increase, the challenges of visual analysis become more complex.This thesis presents work utilizing algorithmically extracted patterns as guidance during interactive data exploration processes, employing information visualization techniques. It provides efficient analysis by taking advantage of fast pattern identification techniques as well as making use of the domain expertise of the analyst. In particular, the presented research is concerned with the issues of analysing categorical data, where the values are names without any inherent order or distance; mixed data, including a combination of categorical and numerical data; and high dimensional data, including hundreds or even thousands of variables.The contributions of the thesis include a quantification method, assigning numerical values to categorical data, which utilizes an automated method to define category similarities based on underlying data structures, and integrates relationships within numerical variables into the quantification when dealing with mixed data sets. The quantification is incorporated in an interactive analysis pipeline where it provides suggestions for numerical representations, which may interactively be adjusted by the analyst. The interactive quantification enables exploration using commonly available visualization methods for numerical data. Within the context of categorical data analysis, this thesis also contributes the first user study evaluating the performance of what are currently the two main visualization approaches for categorical data analysis.Furthermore, this thesis contributes two dimensionality reduction approaches, which aim at preserving structure while reducing dimensionality, and provide flexible and user-controlled dimensionality reduction. Through algorithmic quality metric analysis, where each metric represents a structure of interest, potentially interesting variables are extracted from the high dimensional data. The automatically identified structures are visually displayed, using various visualization methods, and act as guidance in the selection of interesting variable subsets for further analysis. The visual representations furthermore provide overview of structures within the high dimensional data set and may, through this, aid in focusing subsequent analysis, as well as enabling interactive exploration of the full high dimensional data set and selected variable subsets. The thesis also contributes the application of algorithmically guided approaches for high dimensional data exploration in the rapidly growing field of microbiology, through the design and development of a quality-guided interactive system in collaboration with microbiologists.
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