| 1. |
- Lidberg, Tina, 1982-, et al.
(författare)
-
Environmental impact of energy refurbishment of buildings within different district heating systems
- 2018
-
Ingår i: Applied Energy. - : ELSEVIER SCI LTD. - 0306-2619 .- 1872-9118. ; 227, s. 231-238
-
Tidskriftsartikel (refereegranskat)abstract
- The refurbishment of existing buildings is often considered a way to reduce energy use and CO2 emissions in the building stock. This study analyses the primary energy and CO2 impact of refurbishing a multi-family house with different refurbishment packages, given various district heating systems. Four models of typical district heating systems were defined to represent the Swedish district heating sector. The refurbishment packages were chosen to represent typical, yet innovative ways to improve the energy efficiency and indoor climate of a multi-family house. The study was made from a system perspective, including the valuation of changes in electricity use on the margin. The results show a significant difference in primary energy use for the different refurbishment packages, depending on both the package itself as well as the type of district heating system. While the packages with heat pumps had the lowest final energy use per m(2) of floor area, air heat recovery proved to reduce primary energy use and emissions of CO2-equivalents more, independent of the type of district heating system, as it leads to a smaller increase in electricity use.
|
|
| 2. |
- Sattari, Amir, 1980-
(författare)
-
Investigations of Flow Patterns in Ventilated Rooms Using Particle Image Velocimetry : Applications in a Scaled Room with Rapidly Varying Inflow and over a Wall-Mounted Radiator
- 2015
-
Konstnärligt arbete (övrigt vetenskapligt/konstnärligt)abstract
- This thesis introduces and describes a new experimental setup for examining the effects of pulsating inflow to a ventilated enclosure. The study aimed to test the hypothesis that a pulsating inflow has potential to improve ventilation quality by reducing the stagnation zones through enhanced mixing. The experimental setup, which was a small-scale, two-dimensional (2D), water-filled room model, was successfully designed and manufactured to be able to capture two-dimensional velocity vectors of the entire field using Particle Image Velocimetry (PIV). Using in-house software, it was possible to conclude that for an increase in pulsation frequency or alternatively in the flow rate, the stagnation zones were reduced in size, the distribution of vortices became more homogeneous over the considered domain, and the number of vortices in all scales had increased. Considering the occupied region, the stagnation zones were moved away in a favorable direction from a mixing point of view. In addition, statistical analysis unveiled that in the far-field occupied region of the room model, stronger eddies were developed that we could expect to give rise to improved mixing. As a fundamental experimental study performed in a 2D, small-scale room model with water as operating fluid, we can logically conclude that the positive effect of enhanced mixing through increasing the flow rate could equally be accomplished through applying a pulsating inflow.In addition, this thesis introduces and describes an experimental setup for study of air flow over a wall-mounted radiator in a mockup of a real room, which has been successfully designed and manufactured. In this experimental study, the airflow over an electric radiator without forced convection, a common room-heating technique, was measured and visualized using the 2D PIV technique. Surface blackening due to particle deposition calls for monitoring in detail the local climate over a heating radiator. One mechanism causing particle deposition is turbophoresis, which occurs when the flow is turbulent. Because turbulence plays a role in particle deposition, it is important to identify where the laminar flow over radiator becomes turbulent. The results from several visualization techniques and PIV measurements indicated that for a room with typical radiator heating, the flow over the radiator became agitated after a dimensionless length, 5.0–6.25, based on the radiator thickness.Surface properties are among the influencing factors in particle deposition; therefore, the geometrical properties of different finishing techniques were investigated experimentally using a structured light 3D scanner that revealed differences in roughness among different surface finishing techniques. To investigate the resistance to airflow along the surface and the turbulence generated by the surfaces, we recorded the boundary layer flow over the surfaces in a special flow rig, which revealed that the types of surface finishing methods differed very little in their resistance and therefore their influence on the deposition velocity is probably small.
|
|
| 3. |
- Lindberg, Siv M, et al.
(författare)
-
A product semantic study of the influence of the sense of touch on the evaluation of wood-based materials
- 2013
-
Ingår i: Materials & design. - : Elsevier BV. - 0264-1275 .- 1873-4197 .- 0261-3069. ; 52, s. 300-307
-
Tidskriftsartikel (refereegranskat)abstract
- Based on product semantics, this study investigated how the tactile attributes of wood and wood-based composites are perceived and interpreted semantically. The wood-based samples included ash, birch, elm, oak, pine, OSB (oriented strand board), two wood pulp-reinforced polylactide composites, Comp A and B and one wood-fiber reinforced polypropene composite, Comp C. The subjects rated the samples by the descriptive words natural, exclusive, eco-. friendly, rough, inexpensive, reliable, warm, modern, snug and solid. The most significant differences between the samples were found for roughness and for the descriptors, reliable, natural and solid. A principal component analysis yielded three attributes based on the tactile perceptions: reliable, old-. fashioned and smooth. The solid wood pieces were perceived as natural and oak was perceived as being exclusive. The composite materials presented a greater variation in terms of perceived attributes than the wood specimens.
|
|
| 4. |
- Lidberg, Tina, 1982-, et al.
(författare)
-
Comparing different building energy efficiency refurbishment packages performed within different district heating systems
- 2017
-
Ingår i: Energy Procedia. - : Elsevier BV. - 1876-6102. ; 105, s. 1719-1724, s. 1719-1724, s. 1719-1724
-
Tidskriftsartikel (refereegranskat)abstract
- This study analyses the differences in primary energy (PE) use of a multi-family building refurbished with different refurbishment packages situated in different district heating systems (DHS). Four models of typical DHS are defined to represent the Swedish DH sector. The refurbishment packages are chosen to represent typical, yet innovative ways to improve the energy efficiency of a representative multi-family building in Sweden. The study was made from a broad system perspective, including valuation of changes in electricity use on the margin. The results show a significant difference in PE savings for the different refurbishment packages, depending on both the package itself as well as the type of DHS. Also, the package giving the lowest specific energy use per m2 was not the one which saved the most PE. © 2017 The Authors.
|
|
| 5. |
- Sattari, Amir, 1980-, et al.
(författare)
-
INDUSTRIAL NANOPARTICLES HEALTH RISKS AND ADVANTAGES OF A DECENT INDUSTRIAL VENTILATION SYSTEM IN REDUCING THE RELATED RISKS
- 2012
-
Ingår i: INDUSTRIAL NANOPARTICLES HEALTH RISKS AND ADVANTAGES OF A DECENT INDUSTRIAL VENTILATION SYSTEM IN REDUCING THE RELATED RISKS. ; , s. -6
-
Konferensbidrag (refereegranskat)abstract
- With the fast-growing use of nanoparticles (NPs) in a wide range of production and manufacturing processes, and great health and environmental risks associated to NPs, it is important to treat the industry-produced NPs in a proper way. Ventilation of industrial workplaces lies within the concept of sustainability challenges for the development of nanoproducts. Due to the decreased grain size of material to nano limits and thus the appearance of either new or changed properties, health risk of workers in such environments is critical concerning the complicated and unknown characteristics of nanoparticles. There is great evidence over the past few years that ultrafine particles and especially NPs in the breathing air are strong toxins. Different mitigation measures for air-borne nanoparticles in industrial workplaces are substitution, engineering controls such as ventilation and provision of personal protective equipment. In this paper selection criteria for ventilation systems and different ventilation methods (hood ventilation and global enclosure/room ventilation systems) as engineering controls of nanoparticles within industrial enclosures will be reviewed. Novel methods for improvement of ventilation efficiency in general and industrial work places with an eye on ventilation of nanoparticles will be presented.
|
|
| 6. |
- Gren, Åsa, et al.
(författare)
-
How smart is smart growth? : Examining the environmental validation behind city compaction
- 2019
-
Ingår i: Ambio. - : Springer Netherlands. - 0044-7447 .- 1654-7209. ; 48:6, s. 580-589
-
Forskningsöversikt (refereegranskat)abstract
- Smart growth (SG) is widely adopted by planners and policy makers as an environmentally friendly way of building cities. In this paper, we analyze the environmental validity of the SG-approach based on a review of the scientific literature. We found a lack of proof of environmental gains, in combination with a great inconsistency in the measurements of different SG attributes. We found that a surprisingly limited number of studies have actually examined the environmental rationales behind SG, with 34% of those studies displaying negative environmental outcomes of SG. Based on the insights from the review, we propose that research within this context must first be founded in more advanced and consistent knowledge of geographic and spatial analyses. Second, it needs to a greater degree be based on a system's understanding of urban processes. Third, it needs to aim at making cities more resilient, e.g., against climate-change effects.
|
|
| 7. |
- Ljunggren Söderman, Maria, 1967, et al.
(författare)
-
Integrated Economic and Environmental Assessment of Waste Policy Instruments
- 2016
-
Ingår i: Sustainability. - : MDPI AG. - 2071-1050. ; 8:5
-
Tidskriftsartikel (refereegranskat)abstract
- The need for new policy instruments supporting the on-going transition from end-of-pipe waste treatment to resource management has been recognized in European policy. Instruments need to be carefully assessed before implementation to promote the desired changes and avoid problem shifting. Mathematical models may assist policy makers in such assessments. This paper presents a set of soft-linked models for assessing the economic and environmental impacts of policy instruments for both the prevention and management of waste and discusses its strengths and limitations. Consisting of (1) a macro-economic model, (2) a systems engineering model for waste management and (3) a life cycle assessment model for waste management, the set is primarily suited to assessing market-based instruments and environmental regulations. Considerable resources were needed for developing and using the set, and there are clear limits as to what can be addressed. However, if only one of the models had been used, neither the range of instruments nor the scope of impacts would have been possible to cover. Furthermore, soft-linked models allow many disciplines to contribute within one harmonized framework. Such integrated assessments may become increasingly useful for continuing the implementation of policy for sustainable governance of society's material resources.
|
|
| 8. |
- Dabhilkar, Mandar, et al.
(författare)
-
Supplier selection or collaboration? : Determining factors of performance improvement when outsourcing manufacturing
- 2009
-
Ingår i: Journal of Purchasing and Supply Management. - : Elsevier BV. - 1478-4092 .- 1873-6505. ; 15:3, s. 143-153
-
Tidskriftsartikel (refereegranskat)abstract
- An empirical study was designed to determine factors of performance improvement when outsourcing manufacturing. Findings from a survey of 136 manufacturing plants in Sweden show that most of them achieve their outsourcing motives, but not without trade-offs. Factors of performance improvements such as economies of scale or operations in low-cost countries can improve one performance dimension, such as product cost, yet negatively impact volume flexibility, speed or product innovation. The results show part characteristics and supplier operating capabilities are more important than supplier relationship strategies when outsourcing manufacturing, meaning that supplier selection trumps supplier collaboration in the make-or-buy decision.
|
|
| 9. |
- Petrović, Bojana, et al.
(författare)
-
Carbon Assessment of a Wooden Single-Family Building : Focusing on Re-Used Building Products
- 2024
-
Ingår i: Buildings. - : MDPI. - 2075-5309. ; 14:3
-
Tidskriftsartikel (refereegranskat)abstract
- Previous research has shown a lack of studies with comparisons between primary (virgin) and secondary (re-used) building materials, and their embodied emissions. The creation of different scenarios comparing the environmental impact of virgin vs. re-used materials is also motivated by the scarcity of raw materials in the world and the emergency of mitigating greenhouse gas (GHG) emissions from buildings. The aim of this study was to investigate scenarios, including new vs. re-used building products, applying the LCA method for a wooden single-family building. The findings showed a 23% reduction potential for total released (positive) CO2e when comparing the Reference scenario with Scenario I, using re-used wooden-based materials. Further, Scenario II, using all re-used building materials except for installations, showed a 59% CO2e reduction potential compared to the Reference scenario. Finally, Scenario III, which assumes all re-used building products, showed a 92% decreased global warming potential (GWP) impact compared to the Reference scenario. However, when including biogenic carbon and benefits (A5 and D module), the Reference scenario, based on newly produced wooden building materials, has the largest negative GHG emissions. It can be concluded that the re-use of building products leads to significant carbon savings compared to using new building products.
|
|
| 10. |
- Wlazlak, Paraskeva, et al.
(författare)
-
Original equipment manufacturer (OEM)-supplier integration to prepare for production ramp-up
- 2019
-
Ingår i: Journal of Manufacturing Technology Management. - : Emerald Group Publishing Limited. - 1741-038X .- 1758-7786. ; 30:2, s. 506-530
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose: Although prior research provides evidence that production ramp-up is often disrupted by supplier-related problems, it fails to discuss how the original equipment manufacturer (OEM) and various types of suppliers integrate their functions and operations to secure preparations for production ramp-up. The purpose of this paper is to investigate OEM–supplier integration in a new product development (NPD) project to prepare for production ramp-up.Design/methodology/approach: The results presented in this paper are based on a real-time, longitudinal study of a single collaborative NPD project in the mechanical engineering industry. The NPD project involves seven suppliers and it is carried out in a large Swedish company (the OEM) and fits the theory-elaborating approach of this research.Findings: This study argues that the aspect of timing in OEM–supplier integration, the OEM’s research and development (R&D) attitude toward collaboration and the OEM’s (R&D) operating procedure are challenges affecting the preparation for production ramp-up. The following three mechanisms to facilitate OEM–supplier integration in order to prepare for production ramp-up are also discussed: the mediator’s role, the OEM’s face-to-face meeting at the project level and suppliers’ formal face-to-face meetings with the OEM and internally.Originality/value: This paper elaborates on and extends prior research on production ramp-up by conducting an empirical analysis that incorporates supplier integration in NPD. It bridges the gap between the literature on production ramp-up and on supplier integration in NPD and clearly indicates that supplier integration is an important prerequisite for successful production ramp-up.
|
|
