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  • 401.
    Almssad, Asaad
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Almusaed, Amjad
    Archcrea Institute.
    Bio-Ecological Sustainable Windows2005In: The International Conference Sustainable Building 2005 SB05, Tokyo: SB05Tokyo National Conference Board , 2005, p. 31-34Conference paper (Refereed)
    Abstract [en]

    Window is a vital part of any house they permit natural light into the house as long as views and fresh air. In the same time we can consider that the window is an extremely influential factor in climatic design, as the weakest climatic element of the building envelope. Well designed and protected windows improve comfort year round and reduce the need for heating in winter and cooling in summer. Aesthetics appearance, view, and optical performance, are usually quite important to the occupant. In reality, the serious lighting designer cannot take any notice of the energy implications of window choices. New technologies help to resolve the historic problem of the transaction between windows that reflect unwanted solar gains in the summer and those that admit a maximum quantity of useful light. Well-designed windows and shading devices allow solar heat gain in winter and shade and ventilation in summer while providing enough day lighting. Solar gain achieved by heaving 60% of the building’s windows orientated correctly can reduce the heating load of  house by _22%.In houses, low solar heat gain coefficient glazing should be used on east and west orientations, while high glazing should be used when passive solar and day lighting are being utilized.

    Today’s window technologies can replace more primitive strategies for shielding interior spaces from unwanted sunlight, such as tinted windows and curtains.

  • 402.
    Almssad, Asaad
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Almusaed, Amjad
    Archcrea Institute.
    Efficient daylighting approach by means of light-shelve device adequate for habitat program in Aarhus City2014In: International Journal of Smart Grid and Clean Energy, ISSN 2315-4462, Vol. 3, no 4, p. 441-453Article in journal (Refereed)
    Abstract [en]

    The concepts of light shelves consist of windows that have face towards the sun, which receive a vast quantity of energy that could be used for healthy day lighting. This paper debates a main assessment, investigates the optimization of daylight requirement by means of light shelves system. An experimental test was carried out assessing the measurements and lighting simulations of a model of a building in order to elucidate the characteristics of indoor lighting. Light shelf is an architectural element that permits daylight to enter deep into a building. It constitutes an optimal solution for an incorrect building orientation and less sunny days. The essential objective of this study is to highlight the vital role of light shelves in residential buildings in northern Europa where the requirement is to improve the daylight in the interior functional spaces. The main objects of this paper are to investigate the effect of daylight in the interior functional spaces using light shelves, the effect of natural light diffusion in interior space in the period of low daylight season, and glare effect in this field. This paper investigates a procedure for analysing the daylight performance using software habitat function

  • 403.
    Almssad, Asaad
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Almusaed, Amjad
    Albasrah University, Albasrah, Iraq.
    Environmental reply to vernacular habitat conformation from a vast areas of Scandinavia2015In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 48, p. 825-834Article in journal (Refereed)
    Abstract [en]

    There are many original ideas and useful system inputs embedded in the building of human settlements in Scandinavian regions, where the landscape and habitat are strongly interconnected. A cold climate and strong winds are the most prominent risks that affect habitats. The Longhouse is the foremost traditional habitat in the Scandinavian region, dating back to the Iron Age, 2000 BC. This study examines the influence of climate on the conformation of habitats. Climate had a solid impact on the conceptions of habitat form and internal space. Wind and extreme temperatures had firming consequences on the housing arrangements, layouts, orientations, and building materials used in the construction process. Habitats from this region were located in an optimal arrangement, and the south orientation was used effectively. This investigation will provide an evaluative interpretation and analysis of the real facts of vernacular habitats in the context of energy efficiency and ecological concepts, considering human settlement patterns, architectural creation and building material uses. (C) 2015 Elsevier Ltd. All rights reserved.

  • 404. Almssad, Asaad
    et al.
    Almusaed, Amjad
    Archcrea Institute.
    Green building: The optimal solution to combat the negative effects of global climate change2011In: UIA2011 TOKYO Academic Program: Research Papers and Design Works, Tokyo, Japan: The Japan Institute of Architects , 2011, p. 30303-Conference paper (Refereed)
  • 405.
    Almssad, Asaad
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Almusaed, Amjad
    Archcrea Institute.
    Green housing: The optimal Solution To Combat The Negative Effects Of Global Climatechange2010In: 3rd International Conference Palenc 2010 jointly organised with EPIC 2010 & 1st Cool Roofs Conference, University of Athens, Greece , 2010Conference paper (Refereed)
    Abstract [en]

    No Architectural concept is complete without green areas. The vital mission of biophilic architecture is to revised conceptualization of architecture in response to a myriad of contemporary concerns about the effects of human activity. Our earth is warming more rapidly than it has in the past according to the research of scientists. The green building of biophilic architecture combines the interests of sustainability, environmental consciousness, green areas of the large nature, and organic approaches to evolve design solutions from these requirements and from the characteristics of the site, its neighborhood context, and the local microclimate and topography. The biophilic concept provides us with the opportunity to reach extremely low levels of energy consumption by employing high quality, cost-efficient measures to general architectural components - such measures are in turn off advantage to the ecology and economy sector. Our essential task of this research is to make of the green covering a human strategy in urban and architectural manner and to be a human culture with helping of local governments; we can acquire the competent legislation, which protect our life and environment.

  • 406.
    Almssad, Asaad
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Almusaed, Amjad
    Archcrea Institute.
    Kalil Almusaed, Zaki
    Heat Island Effects Upon The Human Life On The City Of Basrah2007In: Building Low Energy Cooling and Advanced Ventilation Technologies in the 21st Century: 2nd PALENC Conference 28th AIVC Conference / [ed] M. Santamouris, P. Wouters, Crete island: University of Athens , 2007, p. 45-47Conference paper (Refereed)
    Abstract [en]

    After the terrible consequence of the Iraq –Iran war and recently USA attack over Iraq the urban green covering disappeared from large areas of the city, beside the extension of the building over the green areas. The negative effects of this phenomenon over human’s thermal comfort become more perceptive. Today we can observe clearly the negative effect of urban heat island in the center of Basra city, precisely in physical frameworks of the city; we can observe a typical phenomenon with a large negative effect for the period of summer heating that is a natural thermodynamic phenomenon. In the surfaces of physical framework, in the core of day between 12-15 pm, the sun is shining perpendicular above the earth surfaces (framework physic). Consequently the temperature on the earth surfaces increases surprisingly up to 60 ºC. Therefore there occurs a difference of temperature between the earth surfaces and cosmos space which conduce to generate a gigantic colonization of air from the earth surface to cosmos space, such resultants of this phenomenon is no air zones and under pressure on earth surfaces, with the intention of making a nasal bleeding, which seeking for a medical intervention aide.

  • 407.
    Almstedt, Åsa
    et al.
    Umeå universitet, Kulturgeografi.
    Brouder, Patrick
    Karlsson, Svante
    Umeå universitet, Institutionen för geografi och ekonomisk historia.
    Lundmark, Linda
    Umeå universitet, Institutionen för geografi och ekonomisk historia.
    Beyond Post-productivism: From Rural Policy Discource to Rural Diversity2014In: European Countryside, ISSN 1803-8417, E-ISSN 1803-8417, Vol. 6, no 4, p. 297-306Article in journal (Refereed)
    Abstract [en]

    There has been a strong discourse in public policy aimed at transforming rural places from venues of primary production into truly diverse socioeconomic landscapes. Yet conceptualisations of the rural as envisioned in the policy and politics of the ‘new economy’ often prove to be elusive on the ground. However, post-productive activity in rural areas has become a major focus for rural studies scholars. This paper investigates the ideas of post-productivism in the existing literature, and argues for a holistic understanding of post-productivism as an idea and political ambition rather than an imperative and irreversible change of rural economic activity. The purpose of the study is to make clear the division between post-productivism and the related concepts of post-production and post-productive activities in order to better understand processes of rural change in relation to different geographical contexts. It is argued that post-productivism as a concept stands apart from de facto post-production and alternative concepts such as multifunctionality and should be regarded as part of broader regional development discourses. The paper outlines several important fields in which post-productivism is a necessary component for rural transformation and development. While it is not always easily captured in indicators or empirical studies in rural locations, post- productivism exists at the level of discourse and planning and thus has real effects on the ground. The paper concludes by offering suggestions on how to apply the concepts of post-productivism, post-production and multifunctionality in future studies. 

  • 408.
    Almusaed, Amjad
    et al.
    Archcrea Institute.
    Almssad, Asaad
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Bioclimatic Interpretation Over Vernacular Houses From Historical city Basrah.2006In: PLEA 2006: 23rd International Conference on Passive and Low Energy Architecture., Geneve: Universite de Geneve , 2006, p. 87-91Conference paper (Refereed)
    Abstract [en]

    Basrah’s climate is hot, dry summer, mild to cold winter, and a pleasant spring and fall. The old builders from this region putted a big effort to create passive bioclimatic houses that corresponds the negative effects Basrah’s macroclimate. The courtyard is the central and dominant space in the house plan with a direct access to the living spaces. Houses from the city are compact with interior courtyard; the streets are sinuous and pass through houses volumes. The shady interior courtyard has the effect that the rooms do not communicate directly with the overheated air outside, but through intermediate buffer spaces. In the mean time between courtyard and street at least a wall or a building is always interposed. The House plan had an endomorphic form, (open tree form). The volumes were concept to create shadow which helps to move the air by natural movement to the deep superior side, that can be achieve through special holes. The architectural elements are strongly decorated, reproducing special typologies and traditional houses. Open spaces, covered by large roofs, are interesting due to the mix of diffuse light and shade that are an essential aesthetic factor in these buildings.

  • 409.
    Almusaed, Amjad
    et al.
    Archcrea Institute.
    Almssad, Asaad
    Biophilic Architecture,: The Concept Of Healthy Sustainable Architecture,2006In: PLEA 2006: 23rd International Conference on Passiveand Low Energy Architecture, Geneve: Universite de Geneve , 2006, p. 383-387Conference paper (Refereed)
    Abstract [en]

    Today, upon reflecting on the various settings and experiences of our lives, we should be able to find some fairly close matches between characteristics we like and characteristics that would have improved our chances of survival. In our course we perceive that the natural contiguous keeps us healthy and in turn, probably promotes physical performance as well. Occupants of built environments don’t want simply to work, play, eat, or sleep in a functional building. They want to be inspired, invigorated, comforted, and reassured by their surroundings. They want spaces that will make them more appropriate, comfortable. Biophilic architecture offers an exciting opportunity to achieve environmental, moral, social and economic benefits. Much remains to be understood about energy, environmental and life-cycle processes to engage young and enthusiastic researchers in the world-wide greenly architecture community and for those interested in biophilic architecture. The concept of biophilia deserves a deeper explanation. The hypothesis is that this affiliation leads to positive responses in terms of human performance and health even emotional states. The new movement aims to create environmentally friendly, energy-efficient buildings and developments by effectively managing natural resources.

  • 410.
    Almusaed, Amjad
    et al.
    Archcrea Institute.
    Almssad, Asaad
    Karlstad University, Faculty of Technology and Science, Department of Energy, Environmental and Building Technology.
    Biophilic Habitat: Environment Adaptability In Context Of BioEcological Architectural Conception2010In: 3rd International Conference Palenc 2010 jointly organised with EPIC 2010 & 1st Cool Roofs Conference, University of Athens, Greece , 2010Conference paper (Refereed)
    Abstract [en]

    The vital objective of biophilic habitat is to outline attributes and put them into a clear, sensible, organized format so developers, designers, planners, and architects can learn about the importance of a connection to the natural environment in all their building projects. Renew ability is the key to our human range and our prime resource for architecture. Every site is definite as to its location, natural relief, local vegetation, and its macro-microclimate.

    Biophilic habitat becomes an original utterance in social requirement. Moreover, this concept becomes a truly new orientation of human cultural life. Biophilic habitat is a part of a new concept in architecture, that work intensive with human health, ecology and sustainability precepts, such a integrate part of architectural formation which must be in optimal proportion with other buildings material. The position of green covering and its area depend basically on the category of functions that occur under this area. Biophilic habitat produces buildings that use less energy to operate because they feature efficient designs, materials and systems. The majority biophilic architectures have highly competent heating, cooling, ventilation, lighting systems, and appliances. In addition, these biophilic restructures are built of energy-efficient materials carefully installed to prevent the loss of conditioned.

  • 411.
    Almusaed, Amjad
    et al.
    Archcrea Institute.
    Almssad, Asaad
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Building materials in eco-energy houses from Iraq and Iran2015In: Case Studies in Construction Materials Journal, ISSN 2214-5095, Vol. 1, p. 42-54Article in journal (Refereed)
    Abstract [en]

    Builders from the Western part of Asia are trained to make buildings that can fulfil certain required functions while giving full consideration to all sites and environmental conditions. The research covers the zone between Iraq and Iran. The first investigated region is the ‘‘Mesopotamian Marshes’’ or Iraqi-Iran Marshes, a wetland zone situated in southern Iraq and partially in southwestern Iran. The other region is a desert district, which includes a prominent part of the southern and western parts of Iraq and part of Iran. The last is the centre city of Basra. The building materials were the most important building element that affected the conformation of vernacular habitats from the western part of Asia in general and the Iraq–Iran area in particular. In this study, we needed to focus on the effects of ecological and energy-efficiency processes in creating vernacular habitats and the selection of optimal building systems and materials in this part of the world, which can be an essential point for sustainable environmental building processes in the future. Reeds, clay, straw, bricks, and wood were the most popular building materials used by builders from this region. The impact of building material on the environment embodies the essential method implicitly significant in this research to effectively determine traditional building materials in the environment, in addition to comparative analysis. This presents an essential factor of our analysis, in addition to the impact of environments on building systems. The main target of this study is to benefit designers and building engineers in their pursuit to find optimal and competent solutions suitable for specific local microclimates using traditional methods in the design process that are sustainable and ecological.

  • 412.
    Almusaed, Amjad
    et al.
    Archcrea Institute.
    Almssad, Asaad
    Umeå Unversitet.
    Improvement of Thermal Insulation by Environmental Means2012In: Effective Thermal Insulation: The Operative Factor Of A Passive Buildning Model / [ed] Amjad Almusaed, Croatia: InTech, 2012, p. 3-22Chapter in book (Refereed)
  • 413.
    Almusaed, Amjad
    et al.
    Archcrea Institute.
    Almssad, AsaadKarlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences.
    Insulation Materials in Context of Sustainability2016Collection (editor) (Refereed)
  • 414.
    Almusaed, Amjad
    et al.
    archcrea-institute.
    Almssad, Asaad
    Passive and Low Energy Housing, Architectural Hypothesis upon Thermalperformance of Sustainable Habitat Management2011In: UIA2011 TOKYO Academic Program: Research Papers and Design Works, Tokyo: The Japan Institute of Architects. , 2011, p. 30302-Conference paper (Refereed)
  • 415.
    Almusaed, Amjad
    et al.
    Archcrea Institute.
    Almssad, Asaad
    Umeå universitet.
    Passive and Low Energy Housing by Optimization2012In: Effective Thermal Insulation: The Operative Factor Of A Passive Buildning Model / [ed] Amjad Almusaed, Croatia: InTech, 2012, p. 23-42Chapter in book (Refereed)
  • 416.
    Almusaed, Amjad
    et al.
    Archcrea Institute.
    Almssad, Asaad
    Passive And Low Energy Housing: In The Context Of “Archie-Metrics”Concept"2010In: lmssad, Rhodes Island: University of Athens, Greece , 2010Conference paper (Refereed)
    Abstract [en]

    The house is not only a roof, but also a home, the place where it is formed the moral climate and on which lasts the family spirit. The architectural product, being a product of the human work, a long time user product, like any other product it has not only to be produced but also to get the user’s disposal. The passive and low energy housing represents one of the most consistent concepts of sustainable building and brings with consideration of energy saving concept.

    Presently becomes incorrect work manner when we take the building phenomenon such as (passive and low energy building), detached from the large concept of architecture. Energy in

    passive and low energy building is an important factor; but it has an abstract act without human sentiments. Economy is other factor; all these factors classified such constant value. The human comfort is a vital aim of architecture, and it classified such variable level. The interaction always appears between the energy such abstract act and human comfort such human feeling. The balancing condition is extremely complex. Our job in this investigation is to establish a commune area by architectural conjecture over passive and low energy building.

  • 417.
    Almusaed, Amjad
    et al.
    Archcrea Institute.
    Almssad, Asaad
    Vernacular Passive Houses From Aarhus City2006In: PLEA 2006: 23rd International Conference on Passive and Low Energy Architecture., Geneve: Universite de Geneve , 2006, p. 91-94Conference paper (Refereed)
    Abstract [en]

    Danish landscape and Danish building are inseparable. Aarhus is a beautiful city situate in the western part of Denmark, and the eastern part of Jutland. Long house or one wing house is a traditional type of house that is dominant in Aarhus city, and other parts of Denmark, which goes back to the Iron Age, c.2000B.C. The aggressive effect of wind obliges builder to find a practical solutions to combat the negative effect of strong wind. Wind breaks around houses is a widespread tradition for determinate a better comfort around house and to save energy. The thermal influence on the built form and orientation of buildings has the strongest influence in the countryside.

  • 418.
    Almusaed, Amjad
    et al.
    Basra University, Iraq.
    Almssad, Asaad
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Alasadi, Asaad
    Basra University, Iraq.
    Analytical interpretation of energy efficiency concepts in the housing design process from hot climate2019In: Journal of Building Engineering, ISSN 2352-7102, Vol. 21, p. 254-266Article in journal (Refereed)
    Abstract [en]

    The classical understanding of an architectural product shows architecture as a series of complex activities, which aims to create an optimal material framework with well-organized functional spaces that can meet the material and human spiritual requirements. The vision of a multifaceted architecture shows that it is necessary to design and work cooperatively with an architectural theory to transform the lateral conceptual viewer of the multilateral design process. The effort has to focus on ensuring the active collaboration of sciences and techniques with the creative building design process. The real stages of house design theory still insufficiently incorporate natural phenomena such as thermography, climatology, aerodynamics, and thermodynamics in the building design approach. The primary target of this research is to define an efficient method of building design in which essential aspects are considered during the first phase of design ideas. The study concluded that using a classical design model is respectable. However, it can bring many mistakes in the confirmation of a holistic design assignment related to energy, thermal comfort, and economic factors that represents an essential tool for architectural creation products where the innovative model proceeds with all design elements, activities and space roles which can reunify in the interpretation of functional spaces by creating an interspace with a consistency habitat environment.

  • 419.
    Almusaed, Amjad
    et al.
    Archcrea Institute.
    Almssad, Asaad
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Almusaed, Ali
    Towards a Zero Energy House Strategy Fitting For South Iraq climate2008In: Passive and Low Energy Architecture 2008 Conference / [ed] Paul Kenny, Vivienne Brophy, J. Owen Lewis, Dublin: University College Dublin , 2008, p. 40-44Conference paper (Refereed)
  • 420.
    Almusaed, Amjad
    et al.
    Archcrea Institute.
    Almssad, Asaad
    Nathir, Ameer M
    Shading Effects Upon Cooling House Strategy In Iraq2007In: Building Low Energy Cooling and Advanced Ventilation Technologies in the 21st Century: 2nd PALENC Conference 28th AIVC Conference / [ed] M. Santamouris, P. Wouters, Crete island: University of Athens , 2007, p. 40-44Conference paper (Refereed)
    Abstract [en]

    Macroclimatic forces have been important factors ever since man first constructed shelter. Throughout architectural history, local buildings have used great in providing the most comfortable internal conditions possible within the exigencies and constraints of local climate. The habitual living way in Iraq is accurately reflected in the households’ organization, in their volumetric configuration, in the forms of useful locations they engender. Houses are compact with interior courtyard; the streets are sinuous and pass through houses volumes. The shady interior courtyard has the effect that the rooms do not communicate directly with the overheated air outside, but through intermediate buffer spaces. In the mean time between courtyard and street at least a wall or a building is always interposed. This isolation from the street indicates concerns for defense. The architectural elements are strongly decorated, reproducing special typologies and traditional houses. The socials relations are strong, a situation which leads to personal-social spaces. The shadow is wanted to create both by means of architectural details and volumes, which have become a landmark of the local architecture specific character, and by means of natural elements (vegetation, water, etc.). The northern orientation is perfect for the summer functional rooms.

  • 421. Almusaed, Amjad
    et al.
    Almusad, Asaad
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Natural Lighting Efficiency By Means of Sun- Skylight-Tubes2014In: International Journal of Engineering and Advanced Technology, ISSN 2249-8958, E-ISSN 2249-8958, Vol. 3, no 3, p. 16-20Article in journal (Refereed)
    Abstract [en]

    The notion of comfort a luminous ambience refers to the distribution of luminance and chromatic ties on the interior envelope of a space that is one of different fields of vision for a subject within an ambience. Luminance and chromatic ties are at present not often studied as far as comfort in buildings is concerned. Sun lighting and bioclimatic concept is inseparable considerations when designing a building because of the historical and practical significance of natural lighting in architecture. Sunlight is as old as architecture itself. Human life gets sufficient sunlight, in fact, we use more of 90 % of our day indoor, for this reason, specialists are now seeing how architecture can ameliorate the indoor-outdoor links. At present, by biological and technological investigation the trend is to search backwards towards the previous philosophies and advantages of more indoor / outdoor relationship. Plus homeowners who want to have healthy home environments might want to renew the most relevant facts of technology and biology.

  • 422.
    Alnebratt, Kerstin
    et al.
    Göteborgs universitet.
    Rönnblom, Malin
    Umeå universitet, Umeå centrum för genusstudier (UCGS).
    Feminism som byråkrati: Jämställdhetsintegrering som strategi2016Book (Other academic)
    Abstract [sv]

    Feminism som byråkrati beskriver utvecklingen av svensk jämställdhetspolitik. Främst behandlas idén om jämställdhetsintegrering. En historieskrivning, men också en analys. Från början av 1990-talet fram till idag. Vilka frågor och krav har kunnat ställas inom ramen för denna politik? Och inte minst, vad har gjorts omöjligt?

  • 423. Alriksson, Björn
    Ethanol from lignocellulose: Alkali detoxification of dilute-acid spruce hydrolysates2006Licentiate thesis, monograph (Other academic)
  • 424.
    Alriksson, Björn
    Karlstad University, Faculty of Technology and Science, Department of Chemistry and Biomedical Sciences.
    Ethanol from lignocellulose: Alkali detoxification of dilute-acid spruce hydrolysates2006Licentiate thesis, comprehensive summary (Other scientific)
    Abstract [en]

    Detoxification of dilute-acid lignocellulose hydrolysates by treatment with Ca(OH)2 (overliming) efficiently improves the production of fuel ethanol, but is associated with drawbacks like sugar degradation and CaSO4 precipitation. In factorial designed experiments, in which pH and temperature were varied, dilute-acid spruce hydrolysates were treated with Ca(OH)2, NH4OH or NaOH. The concentrations of sugars and inhibitory compounds were measured before and after the treatments. The fermentability was examined using the yeast Saccharomyces cerevisiae and compared with reference fermentations of synthetic medium without inhibitors. The treatment conditions were evaluated by comparing the balanced ethanol yield, which takes both the degradation of sugars and the ethanol production into account. Treatment conditions resulting in excellent fermentability and minimal sugar degradation were possible to find regardless of whether Ca(OH)2, NH4OH or NaOH was used. Balanced ethanol yields higher than those of the reference fermentations were achieved for hydrolysates treated with all three types of alkali. As expected, treatment with Ca(OH)2 gave rise to precipitated CaSO4. The NH4OH treatments gave rise to a brownish precipitate but the amounts of precipitate formed were relatively small. No precipitate was observed in treatments with NaOH. The possibility that the ammonium ions from the NH4OH treatments gave a positive effect as an extra source of nitrogen during the fermentations was excluded after experiments in which NH4Cl was added to the medium. The findings presented can be used to improve the effectiveness of alkali detoxification of lignocellulose hydrolysates and to minimize problems with sugar degradation and formation of precipitates.

  • 425.
    Alriksson, Björn
    Karlstad University, Faculty of Technology and Science, Department of Chemistry and Biomedical Sciences.
    Ethanol from lignocellulose: Management of by-products of hydrolysis2009Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Fuel ethanol can be produced from lignocellulosic materials, such as residues from agriculture and forestry. The polysaccharides of lignocellulose are converted to sugars by hydrolysis and the sugars can then be fermented to ethanol using microorganisms. However, during hydrolysis a wide range of by-products are also generated. By-product formation can affect ethanol yield and productivity. Management of by-products of hydrolysis is therefore important in the development of commercially viable production of cellulosic ethanol.

    Detoxification of inhibitory dilute-acid lignocellulose hydrolysates by treatment with Ca(OH)2 (overliming) efficiently improves the fermentability, but is associated with drawbacks like sugar degradation and CaSO4 precipitation. In factorial designed experiments, in which pH and temperature were varied, dilute-acid spruce hydrolysates were treated with Ca(OH)2, NH4OH or NaOH. The concentrations of sugars and inhibitory compounds were measured before and after the treatments. The fermentability was examined using the yeast Saccharomyces cerevisiae and compared with reference fermentations of synthetic medium without inhibitors. The treatment conditions were evaluated by comparing the balanced ethanol yield, which takes both the degradation of sugars and the ethanol production into account. Treatment conditions resulting in excellent fermentability and minimal sugar degradation were possible to find regardless of whether Ca(OH)2, NH4OH or NaOH was used. Balanced ethanol yields higher than those of the reference fermentations were achieved for hydrolysates treated with all three types of alkali. As expected, treatment with Ca(OH)2 gave rise to precipitated CaSO4. The NH4OH treatments gave rise to a brownish precipitate but the amounts of precipitate formed were relatively small. No precipitate was observed in treatments with NaOH. The findings presented can be used to improve the effectiveness of alkali detoxification of lignocellulose hydrolysates and to minimize problems with sugar degradation and formation of precipitates.

    Overexpression of different S. cerevisiae genes was investigated with the aim to engineer a biocatalyst with increased inhibitor tolerance. Overexpression of YAP1, a gene encoding a transcription factor, conveyed increased resistance to lignocellulose-derived inhibitors as well as to a dilute-acid hydrolysate of spruce.

    Recombinant Aspergillus niger expressing the Hypocrea jecorina endoglucanase Cel7B was cultivated on spent lignocellulose hydrolysate (stillage). The fungus simultaneously removed inhibitors present in the stillage and produced higher amounts of endoglucanase than when it was grown in a standard medium with comparable monosaccharide content. The concept can be applied for on-site production of enzymes in a cellulose-to-ethanol process and facilitate recycling of the stillage stream.

  • 426.
    Alriksson, Björn
    et al.
    Karlstad University, Division for Chemistry.
    Horváth, Ilona Sárvári
    Karlstad University, Division for Chemistry.
    Sjöde, Anders
    Karlstad University, Division for Chemistry.
    Nilvebrant, Nils-Olof
    Karlstad University, Division for Chemistry.
    Jönsson, Leif J
    Karlstad University, Division for Chemistry.
    Ammonium hydroxide detoxification of spruce acid hydrolysates.2005In: Applied Biochemistry and Biotechnology, ISSN 0273-2289, E-ISSN 1559-0291, Vol. 121-124, p. 911-22Article in journal (Refereed)
    Abstract [en]

    When dilute-acid hydrolysates from spruce are fermented to produce ethanol, detoxification is required to make the hydrolysates fermentable at reasonable rates. Treatment with alkali, usually by overliming, is one of the most efficient approaches. Several nutrients, such as ammonium and phosphate, are added to the hydrolysates prior to fermentation. We investigated the use of NH4OH for simultaneous detoxification and addition of nitrogen source. Treatment with NH4OH compared favorably with Ca(OH)2, Mg(OH)2, Ba(OH)2, and NaOH to improve fermentability using Saccharomyces cerevisiae. Analysis of monosaccharides, furan aldehydes, phenols, and aliphatic acids was performed after the different treatments. The NH4OH treatments, performed at pH 10.0, resulted in a substantial decrease in the concentrations of furfural and hydroxymethylfurfural. Under the conditions studied, NH4OH treatments gave better results than Ca(OH)2 treatments. The addition of an extra nitrogen source in the form of NH4Cl at pH 5.5 did not result in any improvement in fermentability that was comparable to NH4OH treatments at alkaline conditions. The addition of CaCl2 or NH4Cl at pH 5.5 after treatment with NH4OH or Ca(OH)2 resulted in poorer fermentability, and the negative effects were attributed to salt stress. The results strongly suggest that the highly positive effects of NH4OH treatments are owing to chemical conversions rather than stimulation of the yeast cells by ammonium ions during the fermentation.

  • 427.
    Alriksson, Björn
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Chemistry and Biomedical Sciences.
    Rose, Shaunita, H
    Department of Microbiology, University of Stellenbosch, South Africa.
    van Zyl, Wilhelm, H
    Department of Microbiology, University of Stellenbosch, South Africa.
    Sjöde, Anders
    Karlstad University, Faculty of Technology and Science, Department of Chemistry and Biomedical Sciences.
    Nilvebrant, Nils-Olof
    STFI-Packforsk AB, Stockholm, Sweden.
    Jönsson, Leif J.
    Karlstad University, Faculty of Technology and Science, Department of Chemistry and Biomedical Sciences.
    Cellulase Production from Spent Lignocellulose Hydrolysates with Recombinant Aspergillus niger.2009In: Applied and Environmental Microbiology, ISSN 0099-2240, E-ISSN 1098-5336, Vol. 75, no 8, p. 2366-2374Article in journal (Refereed)
  • 428.
    Alriksson, Björn
    et al.
    Karlstad University, Faculty of Technology and Science.
    Sjöde, Anders
    Karlstad University, Faculty of Technology and Science.
    Nilvebrant, Nils-Olof
    STFI-Packforsk, Stockholm, Sweden.
    Jönsson, Leif J.
    Karlstad University, Faculty of Technology and Science.
    Optimal conditions for alkaline detoxification of dilute-acid lignocellulose hydrolysates.2006In: Applied Biochemistry and Biotechnology, ISSN 0273-2289, E-ISSN 1559-0291, Vol. 129-132, p. 599-611Article in journal (Refereed)
    Abstract [en]

    Alkaline detoxification strongly improves the fermentability of dilute-acid hydrolysates in the production of bioethanol from lignocellulose with Saccharomyces cerevisiae. New experiments were performed with NH4OH and NaOH to define optimal conditions for detoxification and make a comparison with Ca(OH)2 treatment feasible. As too harsh conditions lead to sugar degradation, the detoxification treatments were evaluated through the balanced ethanol yield, which takes both the ethanol production and the loss of fermentable sugars into account. The optimization treatments were performed as factorial experiments with 3-h duration and varying pH and temperature. Optimal conditions were found roughly in an area around pH 9.0/60 degrees C for NH4OH treatment and in a narrow area stretching from pH 9.0/80 degrees C to pH 12.0/30 degrees C for NaOH treatment. By optimizing treatment with NH4OH, NaOH, and Ca(OH)2, it was possible to find conditions that resulted in a fermentability that was equal or better than that of a reference fermentation of a synthetic sugar solution without inhibitors, regardless of the type of alkali used. The considerable difference in the amount of precipitate generated after treatment with different types of alkali appears critical for industrial implementation.

  • 429.
    Alriksson, Björn
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Chemistry and Biomedical Sciences.
    Sárvári Horváth, Ilona
    Karlstad University, Faculty of Technology and Science, Department of Chemistry and Biomedical Sciences.
    Jönsson, Leif J.
    Karlstad University, Faculty of Technology and Science, Department of Chemistry and Biomedical Sciences.
    Overexpression of Saccharomyces cerevisiae transcription factor and multidrug resistance genes conveys enhanced resistance to lignocellulose-derived fermentation inhibitors.2010In: Process Biochemistry, ISSN 1359-5113, E-ISSN 1873-3298, Vol. 45, no 2, p. 264-271Article in journal (Refereed)
  • 430.
    Alsharoa, A.
    et al.
    University of Central Florida.
    Ghazzai, Hakim
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Yuksel, M.
    University of Central Florida.
    Kadri, A.
    Qatar Mobility Innovations Center (QMIC), Qatar University.
    Kamal, A. E.
    Iowa State University (ISU), Ames.
    Trajectory optimization for multiple UAVs acting as wireless relays2018In: 2018 IEEE International Conference on Communications Workshops, ICC Workshops 2018 - Proceedings, Institute of Electrical and Electronics Engineers Inc. , 2018, p. 1-6Conference paper (Refereed)
    Abstract [en]

    This paper proposes a novel wireless relay selection scheme involving multiple mobile Unmanned Aerial Vehicles (UAVs) to support communicating ground users. The goal is to optimize the transmit power levels and trajectories of the relaying UAVs in order to maximize the data rate transmission of the ground users which are suffering from the absence of direct link. Assuming that each UAV is initially characterized by a predefined trajectory for a primary task, we propose to modify it whenever it is needed and the energy and trajectory boundaries constraints allow. We propose to solve this problem using an iterative two steps solution; first, a Mixed Integer Linear Programming (MILP) problem is formulated to optimally determine the users- UAVs associations and the UAVs' corresponding transmit power levels. In the second step, an efficient algorithm based on a recursive shrink-and-realign process is proposed to optimize the UAV trajectories. The performance of the proposed method shows advantages in terms of average throughput compared to the predefined trajectories solution.

  • 431. Altun, Z.
    et al.
    Andersson, L.I.
    Blomberg, Lars G
    Karlstad University, Faculty of Technology and Science, Department of Chemistry and Biomedical Sciences.
    Abdel-Rehim, M.
    Some factors affecting the performance of microextraction in packed syringe (MEPS)2008In: submitted to Analyt. Chim. ActaArticle in journal (Refereed)
  • 432.
    Altun, Zeki
    Karlstad University, Division for Chemistry.
    New Techniques for Sample Preparation in Analytical Chemistry2005Licentiate thesis, comprehensive summary (Other scientific)
    Abstract [en]

    Sample preparation is often a bottleneck in systems for chemical analysis. The aim of this work was to investigate and develop new techniques to address some of the shortcomings of current sample preparation methods. The goal has been to provide full automation, on-line coupling to detection systems, short sample preparation times and high-throughput.

    A new technique for sample preparation that can be connected on-line to liquid chromatography (LC) and gas chromatography (GC) has been developed. Microextraction in packed syringe (MEPS) is a new solid-phase extraction (SPE) technique that is miniaturized and can be fully automated. In MEPS approximately 1 mg of sorbent material is inserted into a gas tight syringe (100-250 μL) as a plug. Sample preparation takes place on the packed bed. Evaluation of the technique was done by the determination of local anaesthetics in human plasma samples using MEPS on-line with LC and tandem mass spectrometry (MS-MS). MEPS connected to an autosampler was fully automated and clean-up of the samples took one minute. In addition, in the case of plasma samples the same plug of sorbent could be used for about 100 extractions before it was discarded.

    A further aim of this work was to increase sample preparation throughput. To do that disposable pipette tips were packed with a plug of porous polymer monoliths as sample adsorbent and were then used in connection with 96-well plates and LC-MS-MS. When roscovitine in human plasma and water samples was used as model substance, a 96-plate was handled in two minutes.

  • 433. Altun, Zeki
    New Techniques for Sample Preparation in Analytical Chemistry: - Microextraction in Packed Syringe (MEPS) and Methacrylate Based Monolithic Pipette Tips2008Doctoral thesis, monograph (Other academic)
  • 434.
    Altun, Zeki
    Karlstad University, Faculty of Technology and Science, Department of Chemistry and Biomedical Sciences.
    New Techniques for Sample Preparation in Analytical Chemistry: Microextraction in Packed Syringe (MEPS) and Methacrylate Based Monolithic Pipette Tips2008Doctoral thesis, comprehensive summary (Other scientific)
    Abstract [en]

    Sample preparation is often a bottleneck in systems for chemical analysis. The aim of this work was to investigate and develop new techniques to address some of the shortcomings of current sample preparation methods. The goal has been to provide full automation, on-line coupling to detection systems, short sample preparation times and high-throughput.

    In this work a new technique for sample preparation that can be connected on-line to liquid chromatography (LC) and gas chromatography (GC) has been developed. Microextraction in packed syringe (MEPS) is a new solid-phase extraction (SPE) technique that is miniaturized and can be fully automated. In MEPS approximately 1 mg of sorbent material is inserted into a gas tight syringe (100-250 μL) as a plug. Sample preparation takes place on the packed bed. Evaluation of the technique was done by the determination of local anaesthetics in human plasma samples using MEPS on-line with LC and tandem mass spectrometry (MS-MS). MEPS connected to an autosampler was fully automated and clean-up of the samples took about one minute. In addition, in the case of plasma samples the same plug of sorbent could be used for about 100 extractions before it was discarded.

    A further aim of this work was to increase sample preparation throughput. To do that disposable pipette tips were packed with a plug of porous polymer monoliths as sample adsorbent and were then used in connection with 96-well plates and LC-MS-MS. The evaluation of the methods was done by the analysis of local anaesthetics lidocaine and ropivacaine, and anti-cancer drug roscovitine in plasma samples. When roscovitine and lidocaine in human plasma and water samples were used as model substances, a 96-plate was handled in about two minutes. Further, disposable pipette tips may be produced at low cost and because they are used only once, carry-over is eliminated.

  • 435. Altun, Zeki
    et al.
    Abdel-Rehim, M.
    Blomberg, Lars G
    Karlstad University, Faculty of Technology and Science, Department of Chemistry and Biomedical Sciences.
    New trends in sample preparation: On-line microextraction in packed syringe (MEPS) for LC and GC applications. Part III Determination and validation of local anaesthetics in human plasma samples using a cation-exchange sorbent and MEPS-LC-MS-MS2004In: J. Chromatogr. B, 813 (2004) 129-135Article in journal (Refereed)
  • 436.
    Altun, Zeki
    et al.
    Karlstad University, Division for Chemistry.
    Abdel-Rehim, Mohamed
    Karlstad University, Division for Chemistry.
    Blomberg, Lars G.
    Karlstad University, Division for Chemistry.
    New trends in sample preparation: on-line microextraction in packed syringe (MEPS) for LC and GC applications Part III: Determination and validation of local anaesthetics in human plasma samples using a cation-exchange sorbent, and MEPS–LC–MS–MS2004In: Journal of chromatography. B, ISSN 1570-0232, E-ISSN 1873-376X, Vol. 813, no 1-2, p. 129-135Article in journal (Refereed)
  • 437.
    Altun, Zeki
    et al.
    Karlstad University, Faculty of Technology and Science, Department of Chemistry and Biomedical Sciences.
    Andersson, Lars I.
    AstraZeneca R&D Södertälje, DMPK & BAC, Södertälje, Sweden.
    Blomberg, Lars G.
    Karlstad University, Faculty of Technology and Science, Department of Chemistry and Biomedical Sciences.
    Abdel-Rehim, Mohamed
    Karlstad University, Division for Business and Economics.
    Some Factors Affecting the Performance of Microextraction in Packed Syringe (MEPS)Manuscript (Other academic)
  • 438. Altun, Zeki
    et al.
    Blomberg, Lars G
    Karlstad University, Faculty of Technology and Science, Department of Chemistry and Biomedical Sciences.
    Use of carbon dioxide and ammonia as nebulizer gases in mass spectrometry2002In: Rapid Comm. Mass Spectrometry, 16 (2002) 738-739Article in journal (Refereed)
  • 439.
    Altun, Zeki
    et al.
    Karlstad University, Faculty of Technology and Science.
    Blomberg, Lars G.
    Karlstad University, Faculty of Technology and Science.
    Abdel-Rehim, Mohamed
    AstraZeneca R & D, , Sweden.
    Increasing Sample Preparation Throughput Using Monolithic Methacrylate Polymer as Packing Material for 96-Tip Robotic Device2006In: Journal of Liquid Chromatography & Related Technologies, ISSN 1082-6076, E-ISSN 1520-572X, Vol. 29, no 10, p. 1477-1489Article in journal (Refereed)
  • 440.
    Altun, Zeki
    et al.
    Karlstad University, Division for Chemistry.
    Blomberg, Lars G.
    Karlstad University, Division for Chemistry.
    Abdel-Rehim, Mohamed
    Karlstad University, Division for Chemistry.
    Increasing Sample Preparation Throughput Using Monolithic Methacrylate Polymer as Packing Material for 96-Tips: 2 Minutes per 96-Well Plate2005Manuscript (preprint) (Other academic)
  • 441. Altun, Zeki
    et al.
    Hjelmström, Anette
    Abdel-Rehim, Mohamed
    Blomberg, Lars G
    Karlstad University, Faculty of Technology and Science, Department of Chemistry and Biomedical Sciences.
    Surface Modified Polypropylene Pipette Tips Packed with a Monolithic Plug of Adsorbent for High Throughput Sample Preparation2007In: J. Sep. Sci., 30 (2007) 1964-1972Article in journal (Refereed)
  • 442.
    Altun, Zeki
    et al.
    Karlstad University, Faculty of Technology and Science.
    Hjelmström, Anette
    Karlstad University, Faculty of Technology and Science.
    Abdel-Rehim, Mohamed
    Karlstad University, Faculty of Technology and Science.
    Blomberg, Lars G.
    Karlstad University, Faculty of Technology and Science.
    Surface modified polypropylene pipette tips packed with a monolithic plug of adsorbent for high-throughput sample preparation2007In: Journal of Separation Science, ISSN 1615-9306, E-ISSN 1615-9314, Vol. 30, no 12, p. 1964-1972Article in journal (Refereed)
  • 443. Altun, Zeki
    et al.
    Hjelmström, Anette
    Blomberg, Lars G
    Karlstad University, Faculty of Technology and Science, Department of Chemistry and Biomedical Sciences.
    Abdel-Rehim, Mohamed
    Evaluation of monolithic packed 96-tips for solid-phase extraction of local anesthetics from human plasma for quantitation by liquid chromatography tandem mass spectrometry2008In: J. Liq. Chromatogr. & Relat. Technol , 31 (2008) 743-751Article in journal (Refereed)
  • 444. Altun, Zeki
    et al.
    Jagerdeo, E.
    Blomberg, Lars G
    Karlstad University, Faculty of Technology and Science, Department of Chemistry and Biomedical Sciences.
    Abdel-Rehim, M.
    Drug screening using microextraction in packed syringe (MEPS) / LC-MS utilizing monolithic-based sorbent material,2006In: Journal of Liquid Chromatography and Related Technologies, 29 (2006) 829-839Article in journal (Refereed)
  • 445. Alty, S.
    et al.
    Jakobsson, Andreas
    Computationally Efficient Time-Varying ISAR Imaging2006Conference paper (Refereed)
  • 446. Alty, S.
    et al.
    Jakobsson, Andreas
    The Efficient Evaluation of Cholesky Factors of Centrosymmetric Matrices Using Displacement-Rank Structure2005Report (Other academic)
  • 447. Alty, S. R.
    et al.
    Benesty, J.
    Jakobsson, Andreas
    Efficient Implementation of the Local Capon Spectral Estimate2007Conference paper (Refereed)
  • 448. Alty, S. R.
    et al.
    Jakobsson, Andreas
    Larsson, E. G.
    Efficient implementation of the time-recursive Capon and APES Spectral Estimators2004Conference paper (Refereed)
  • 449. Alty, S. R.
    et al.
    Jakobsson, Andreas
    Larsson, E. G.
    Efficient Time-Recursive Implementation of Matched Filterbank Spectral Estimators2005In: IEEE Transactions on Circuits and Systems I: Fundamental Theory and Applications, Vol. 99, pp. 516-521, March 2005Article in journal (Refereed)
  • 450. Alty, S. R.
    et al.
    Millasseau, S. C.
    Chowienczyk, P.
    Jakobsson, Andreas
    Cardiovascular Disease Prediction using Support Vector Machines2003Conference paper (Refereed)
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