| 1. |
- Adnan, Safdar, et al.
(författare)
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Evaluation of microstructural development in electron beam melted Ti-6Al-4V
- 2012
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Ingår i: Materials Characterization. - : Elsevier BV. - 1044-5803 .- 1873-4189. ; 65, s. 8-15
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Tidskriftsartikel (refereegranskat)abstract
- In the current work an investigation of the microstructures of EBM built Ti-6Al-4V test bars has been performed using OM, SEM, TEM and XRD. It has been found that the prior beta phase, that formed during the initial solidification, possesses a column shaped morphology with growing direction parallel to built direction. Typical (alpha+beta) structures namely Widmanstatten alpha platelets with rod-like beta phase formed on the interfaces of the fine alpha grains, have been observed in the columnar prior beta grains. Grain boundary alpha phase was found to be formed around the boundaries of the columnar prior beta grains. Different phases present in the parts, especially the BCC beta phases have been characterized. The TEWEDX results indicate very high V composition in the beta phase. Results of TEWSAED and XRD also revealed that a superlattice structure could be present in the beta phase. Phase transformation sequence is discussed according to the processing history and the microstructures observed.
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| 2. |
- Alégroth, Emil, 1984, et al.
(författare)
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JAutomate: A tool for system- and acceptance-test automation
- 2013
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Ingår i: Proceedings - IEEE 6th International Conference on Software Testing, Verification and Validation, ICST 2013. - : IEEE. - 9780769549682 ; , s. 439-446
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Konferensbidrag (refereegranskat)abstract
- System- and acceptance-testing are primarily performed with manual practices in current software industry. However, these practices have several issues, e.g. they are tedious, error prone and time consuming with costs up towards 40 percent of the total development cost. Automated test techniques have been proposed as a solution to mitigate these issues, but they generally approach testing from a lower level of system abstraction, leaving a gap for a flexible, high system-level test automation technique/tool. In this paper we present JAutomate, a Visual GUI Testing (VGT) tool that fills this gap by combining image recognition with record and replay functionality for high system-level test automation performed through the system under test's graphical user interface. We present the tool, its benefits compared to other similar techniques and manual testing. In addition, we compare JAutomate with two other VGT tools based on their static properties. Finally, we present the results from a survey with industrial practitioners that identifies testrelated problems that industry is currently facing and discuss how JAutomate can solve or mitigate these problems. © 2013 IEEE.
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| 3. |
- Alégroth, Emil, 1984, et al.
(författare)
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Transitioning manual system test suites to automated testing: An industrial case study
- 2013
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Ingår i: Proceedings - IEEE 6th International Conference on Software Testing, Verification and Validation, ICST 2013. - : IEEE. - 9780769549682 ; , s. 56-65
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Konferensbidrag (refereegranskat)abstract
- Visual GUI testing (VGT) is an emerging technique that provides software companies with the capability to automate previously time-consuming, tedious, and fault prone manual system and acceptance tests. Previous work on VGT has shown that the technique is industrially applicable, but has not addressed the real-world applicability of the technique when used by practitioners on industrial grade systems. This paper presents a case study performed during an industrial project with the goal to transition from manual to automated system testing using VGT. Results of the study show that the VGT transition was successful and that VGT could be applied in the industrial context when performed by practitioners but that there were several problems that first had to be solved, e.g. testing of a distributed system, tool volatility. These problems and solutions have been presented together with qualitative, and quantitative, data about the benefits of the technique compared to manual testing, e.g. greatly improved execution speed, feasible transition and maintenance costs, improved bug finding ability. The study thereby provides valuable, and previously missing, contributions about VGT to both practitioners and researchers. © 2013 IEEE.
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| 4. |
- Alenezi, Ali, et al.
(författare)
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Characteristics of 2 Different Commercially Available Implants with or without Nanotopography
- 2013
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Ingår i: International Journal of Dentistry. - : Hindawi Limited. - 1687-8736 .- 1687-8728. ; 2013:Art. no. 769768
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to assess histologically and histomorphometrically the early bone forming properties after 3 weeks for 2 commercially available implants, one supposedly possessing nanotopography and one without, in a rabbit femur model. Twenty-four implants divided equally into 2 groups were utilized in this study. The first group (P-I MICRO+NANO) was a titanium oxide (TiO2) microblasted and noble gas ion bombarded surface while the second group (Ospol) was anodic oxidized surface with calcium and phosphate incorporation. The implants were placed in the rabbit femur unicortically and were allowed to heal for 3 weeks. After euthanasia, the samples were subjected to histologic sectioning and bone-implant contact and bone area were evaluated histomorphometrically under an optical microscope. The histomorphometric evaluation presented that the P-I MICRO+NANO implants demonstrated significantly higher new bone formation as compared to the Ospol implants. Within the limitations of this study, the results suggested that nanostructures presented significantly higher bone formation after 3 weeks in vivo, and the effect of chemistry was limited, which is indicative that nanotopography is effective at early healing periods.
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| 5. |
- Alenezi, Ali, et al.
(författare)
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Development of a photon induced drug-delivery implant coating
- 2019
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Ingår i: Materials Science and Engineering C. - : Elsevier BV. - 0928-4931 .- 1873-0191. ; 98, s. 619-627
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Tidskriftsartikel (refereegranskat)abstract
- A thin surface coating intended for medical devices such as implants where local drug release is enabled using near infrared light (NIR) as an external stimulus has been developed. The delivery system consists of a thin Poly (N-isopropylacrylamide)-co-acrylamide (PNIPAAm-AAm) polymer layer with incorporated gold nanorods (GNRs). The aspect ratio of the GNRs were chosen to absorb NIR light, thus fitting the biological window of low tissue absorption, to locally heat the polymeric layer to initiate a drug release. Hence, controlled drug delivery from a surface within tissue orchestrated from outside the body is achievable. Composition of the PNIPAAm-AAm co-polymer was systematically varied to find a suitable phase transition temperature for in vivo applications. Differential scanning calorimetry (DSC) analysis showed that PNIPAAm-AAm containing 10% acrylamide had an appropriate phase transition temperature of 42 °C. As visualized by scanning electron microscopy (SEM), the surface coating consisted of 200 nm uniform polymer layer. Quartz crystal microbalance with dissipation monitoring (QCM-D) analysis coupled with in situ NIR irradiation demonstrated a dramatic shift in frequency that was attributed to mass being released from the surface upon irradiation. This mass release correlated well with the drug release profile as determined using UV/VIS spectroscopy with phenol as a model drug. In addition, proof-of-concept of the drug-delivery system was demonstrated by releasing the antibiotic vancomycin to eradicate Staphylococcus epidermidis bacteria in culture.
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| 6. |
- Alenezi, Ali, et al.
(författare)
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Osseointegration effects of local release of strontium ranelate from implant surfaces in rats
- 2019
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Ingår i: Journal of Materials Science: Materials in Medicine. - : Springer Science and Business Media LLC. - 0957-4530 .- 1573-4838. ; 30:10, s. 116-
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND : Numerous studies have reported the beneficial effects of strontium on bone growth, particularly by stimulating osteoblast proliferation and differentiation. Thus, strontium release around implants has been suggested as one possible strategy to enhance implant osseointegration. AIM : This study aimed to evaluate whether the local release of strontium ranelate (Sr-ranelate) from implants coated with mesoporous titania could improve bone formation around implants in an animal model. MATERIALS AND METHODS : Mesoporous titania (MT) thin coatings were formed utilizing the evaporation induced self-assembly (EISA) method using Pluronic (P123) with or without the addition of poly propylene glycol (PPG) to create materials with two different pore sizes. The MT was deposited on disks and mini-screws, both made of cp Ti grade IV. Scanning electron microscopy (SEM) was performed to characterize the MT using a Leo Ultra55 FEG instrument (Zeiss, Oberkochen, Germany). The MT was loaded with Sr-ranelate using soaking and the drug uptake and release kinetics to and from the surfaces were evaluated using quartz crystal microbalance with dissipation monitoring (QCM-D) utilizing a Q-sense E4 instrument. For the in vivo experiment, 24 adult rats were analyzed at two time points of implant healing (2 and 6 weeks). Titanium implants shaped as mini screws were coated with MT films and divided into two groups; supplied with Sr-ranelate (test group) and without Sr-ranelate (control group). Four implants (both test and control) were inserted in the tibia of each rat. The in vivo study was evaluated using histomorphometric analyses of the implant/bone interphase using optical microscopy. RESULTS : SEM images showed the successful formation of evenly distributed MT films covering the entire surface with pore sizes of 6 and 7.2 nm, respectively. The QCM-D analysis revealed an absorption of 3300 ng/cm2 of Sr-ranelate on the 7.2 nm MT, which was about 3 times more than the observed amount on the 6 nm MT (1200 ng/cm2). Both groups showed sustained release of Sr-ranelate from MT coated disks. The histomorphometric analysis revealed no significant differences in bone implant contact (BIC) and bone area (BA) between the implants with Sr-ranelate and implants in the control groups after 2 and 6 weeks of healing (BIC with a p-value of 0.43 after 2 weeks and 0.172 after 6 weeks; BA with a p-value of 0.503 after 2 weeks, and 0.088 after 6 weeks). The mean BIC and BA values within the same group showed significant increase among all groups between 2 and 6 weeks. CONCLUSION : This study could not confirm any positive effects of Sr-ranelate on implant osseointegration.
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| 7. |
- Andersson, Jacob, et al.
(författare)
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Gamification of publication metadata : to playfully explore our data
- 2015
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This report describes a project that aimed to create game concepts and games based on a set of data about research publications. This was done using linked open data, procedural content generation of game content, and iterative game development, with the aim of creating useful games and game concepts.
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| 8. |
- Backlund, Emil, 1988, et al.
(författare)
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Automated User Interaction Analysis for Workflow-Based Web Portals
- 2014
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Ingår i: Software Business. - Cham : Springer. ; 182, s. 148-162
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Konferensbidrag (refereegranskat)abstract
- Success in the software market requires constant improvement of the software. These improvements however have to directly align with the needs of the users of the software. A recent trend in software engineering is to collect post-deployment data about how users use a software system. We report in this paper about a case study with an industrial partner in which (1) we identified which data has to be collected for a web-based portal system, (2) implemented the data collection, and (3) performed an experiment comparing the collected data with answers of the test subjects in a survey.
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| 9. |
- Barkarmo, Sargon, et al.
(författare)
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Enhanced bone healing around nanohydroxyapatite-coated polyetheretherketone implants : An experimental study in rabbit bone
- 2014
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Ingår i: Journal of biomaterials applications. - : Sage Publications. - 0885-3282 .- 1530-8022. ; 29:5, s. 737-747
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Tidskriftsartikel (refereegranskat)abstract
- Objective: To investigate the bone response to threaded polyetheretherketone (PEEK) implants coated with nanohydroxyapatite. Materials and methods: A total of 39 PEEK implants were coated with nanocrystalline hydroxyapatite and 39 uncoated implants were used as controls. The implant surface was characterized by optical interferometry and scanning electron microscope. The implants were inserted in the tibia and femur of 13 rabbits. After 6 weeks of healing, quantitative and qualitative analyses were performed. Results: The test implants showed significantly higher removal torque test values compared with the control group. Histomorphometric evaluation demonstrated higher bone-to-implant contact for the test implants; however, there were no differences in bone area between the groups. Qualitative histological analyses demonstrated inflammatory cellular reactions in close vicinity of both implant surfaces. A two-cell layer of foreign body giant cells was observed irrespective of sample type. Conclusion: Our findings demonstrate that implants with a threaded design render good stability to PEEK in both coated and uncoated implants. Nanohydroxyapatite-coated PEEK implants demonstrated improved bone formation compared with uncoated controls.
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| 10. |
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