Sök i SwePub databas

  Utökad sökning

Träfflista för sökning "LAR1:hh "

Sökning: LAR1:hh

Sortera/gruppera träfflistan
  • Agelis, Sacki, et al. (författare)
  • Visualizing the Potential of Reconfigurable Shuffle-Patterns in Optoelectronic Routers by the Use of MOEMS
  • 2004
  • Ingår i: Proceedings of the IASTED International Conference Communication Systems and Networks. - Calgary, Canada : ACTA Press. - 0-88986-450-0 ; s. 148-154
  • Konferensbidrag (refereegranskat)abstract
    • <p>A reconfigurable high performance multistage router architecture is presented and simulated. The router backbone network is an optical shuffle exchange network that has the power of reconfigurability through the use of micro-optical-electrical mechanical systems (MOEMS). The router is subjected to different application classes. The application classes have different characteristics in terms of symmetric/asymmetric traffic properties. We compare our reconfigurable shuffle-pattern for all three application classes for the specified router architecture.</p>
  • Aghaeipour, Mahtab, et al. (författare)
  • Comparative study of absorption efficiency of inclined and vertical InP nanowires
  • 2017
  • Ingår i: Physics, Simulation, and Photonic Engineering of Photovoltaic Devices VI. - Bellingham, WA : SPIE - International Society for Optical Engineering. - 978-1-5106-0640-1
  • Konferensbidrag (refereegranskat)abstract
    • <p>Geometrically designed III-V nanowire arrays are promising candidates for optoelectronics due to their possibility to excite nanophotonic resonances in absorption spectra. Strong absorption resonances can be obtained by proper tailoring of nanowire diameter, length and pitch. Such enhancement of the light absorption is, however, accompanied by undesired resonance dips at specific wavelengths. In this work, we theoretically show that tilting of the nanowires mitigates the absorption dips by exciting strong Mie resonances. In particular, we derive a theoretical optimum inclination angle of about 30 degrees at which the inclined nanowires gain 8% in absorption efficiency compared to vertically standing nanowires in a spectral region matching the intensity distribution of the sun. The enhancement is due to engineering the excited modes inside the nanowires regarding the symmetry properties of the nanowire/light system without increasing the absorbing material. We expect our results to be important for nanowire-based photovoltaic applications. © 2017 SPIE.</p>
  • Aghaeipour, Mahtab, et al. (författare)
  • Considering Symmetry Properties of InP Nanowire/Light Incidence Systems to Gain Broadband Absorption
  • 2017
  • Ingår i: IEEE Photonics Journal. - Piscataway : IEEE. - 1097-5764 .- 1943-0655. ; 9:3
  • Tidskriftsartikel (refereegranskat)abstract
    • <p>Geometrically designed III-V nanowire arrays are promising candidates for disruptive optoelectronics due to the possibility of obtaining a strongly enhanced absorption resulting from nanophotonic resonance effects. With normally incident light on such vertical nanowire arrays, the absorption spectra exhibit peaks that originate from excitation of HE1m waveguide modes in the constituent nanowires. However, the absorption spectra typically show dips between the absorption peaks. Conventionally, such weak absorption has been counteracted by either making the nanowires longer or by decreasing the pitch of the array, both alternatives effectively increasing the volume of absorbing material in the array. Here, we first study two approaches for compensating the absorption dips by exciting additional Mie resonances: 1) oblique light incidence on vertical InP nanowire arrays and 2) normal light incidence on inclined InP nanowire arrays. We then show that branched nanowires offer a novel route to achieve broadband absorption by taking advantage of simultaneous excitations of Mie resonances in the branches and guided HE1m modes in the stem. Finite element method calculations show that the absorption efficiency is enhanced from 0.72 for vertical nanowires to 0.78 for branched nanowires under normal light incidence. Our work provides new insight for the development of novel efficient photovoltaics with high efficiency and reduced active material volume.</p>
  • Aghaeipour, Mahtab, et al. (författare)
  • Enhanced broadband absorption in nanowire arrays with integrated Bragg reflectors
  • 2018
  • Ingår i: Nanophotonics. - Berlin : De Gruyter Open. - 2192-8614. ; 7:5, s. 819-825
  • Tidskriftsartikel (refereegranskat)abstract
    • <p>A near-unity unselective absorption spectrum is desirable for high-performance photovoltaics. Nanowire arrays are promising candidates for efficient solar cells due to nanophotonic absorption resonances in the solar spectrum. The absorption spectra, however, display undesired dips between the resonance peaks. To achieve improved unselective broadband absorption, we propose to enclose distributed Bragg reflectors (DBRs) in the bottom and top parts of indium phosphide (InP) nanowires, respectively. We theoretically show that by enclosing only two periods of In<sub>0.56</sub>Ga<sub>0.44</sub>As/InPDBRs, an unselective 78% absorption efficiency (72% for nanowires without DBRs)is obtained at normal incidence in the spectral range from 300 nm to 920 nm. Under oblique light incidence, the absorption efficiency is enhanced up to about 85% at an incidence angle of 50º. By increasing the number of DBR periods from two to five, the absorption efficiency is further enhanced up to 95% at normal incidence. In this work we calculated optical spectra for InP nanowires, but the results are expected to be valid for other direct band gap III-V semiconductor materials. We believe that our proposed idea of integrating DBRs in nanowires offers great potential for high-performance photovoltaic applications. ©2018 Håkan Pettersson et al., published by De Gruyter, Berlin/Boston.</p>
  • Aghaeipour, Mahtab, et al. (författare)
  • Enhanced optical absorption in nanowires over a desire range of wavelengths
  • 2017
  • Ingår i: MOC2017 : technical digest of the Twenty-Second Microoptics Conference : November 19-22, 2017, Institute of Industrial Science, The University of Tokyo, Japan. - 978-4-8634-8609-6 - 978-1-5090-4924-0 ; s. 360-361
  • Konferensbidrag (refereegranskat)abstract
    • <p>Engineering optical absorption in nanowires, over a desire range of wavelengths is of importance to design high-performance nanowire-based photovoltaics. To this end, we integrate the nanowires with distributed Bragg reflectors to enhance absorption spectra of the nanowires and relate the consequent enhancement to increasing the optical path lengths of the modes. © 2017 The Japan Society of Applied Physics.</p>
  • Aghaeipour, Mahtab, 1982- (författare)
  • Tailoring the Optical Response of III-V Nanowire Arrays
  • 2017
  • Doktorsavhandling (övrigt vetenskapligt)abstract
    • <p>Semiconductor nanowires show a great deal of promise for applications in a wide range of important fields, including photovoltaics, biomedicine, and information technology. Developing these exciting applications is strongly dependent on understanding the fundamental properties of nanowires, such as their optical resonances and absorption spectra. In this thesis we explore optical absorption spectra of arrays of vertical III-V nanowires with a special emphasis on structures optimized to enhance absorption in the solar spectrum. First, we analyze experimentally determined absorption spectra of both indium phosphide (InP) and gallium phosphide (GaP) nanowire arrays. The study provides an intuitive understanding of how the observed absorption resonances in the nanowires may be tuned as a function of their geometrical parameters and crystal structure. As a consequence, the spectral position of absorption resonances can be precisely controlled through the nanowire diameter. However, the results highlight how the blue-shift in the optical absorption resonances as the diameter of the nanowires decreases comes to a halt at low diameters. The stop point is related to the behavior of the refractive indices of the nanowires. The wavelength of the stop is different for nanowire polytypes of similar dimensions due to differences in their refractive indices. We then present a theoretical argument that it is important to consider symmetry properties when tailoring the optical modes excited in the nanowires for enhanced absorption. We show that absorption spectra may be enhanced compared to vertical nanowires at normal incidence by tilting the nanowires with normal incidence light, or by using off-normal incidence with vertical nanowires. This is because additional optical modes inside the nanowires are excited when the symmetry is broken. Looking forward to omnidirectional applications, we consider branched nanowires as a way to enhance the absorption spectra at normal incidence by taking advantage of simultaneous excitation of the spectrally different optical modes in the branches and the stems. Third, we describe in theoretical terms how integrating distributed Bragg reflectors (DBRs) with the nanowires can improve absorption spectra compared to conventional nanowires. DBRs provide a way to employ light trapping mechanisms which increases the optical path length of the excited modes and thereby improves the absorption of the excited modes. At normal incidence, DBR-nanowires improve the absorption efficiency to 78%, compared to 72% for conventional nanowires. We show that the efficiency is increased to 85% for an off-normal incident angle of 50˚. Overall, our results show that studies of optical resonances in nanowires that take the light-matter interaction into account provide opportunities to develop novel optical and optoelectronic functionalities in nanoscience and nanotechnology.</p>
  • Agostino, Alessandro, et al. (författare)
  • Cloud solution in Business Intelligence for SMEs – vendor and customer perspectives
  • 2013
  • Ingår i: Journal of Intelligence Studies in Business. - Halmstad : Halmstad University. - 2001-015X .- 2001-015X. ; 3:3, s. 5-28
  • Tidskriftsartikel (refereegranskat)abstract
    • <p>The aim of this study was to identify key success factor for SME customers of cloud based Business Intelligence products. A deep interview was made with four producers and a questionnaire was carried out among 36 SMEs. The findings suggest that the most important CSFs were the level of software functionalities, the ubiquitous access to data, responsive answers to customer support requests, handling large amounts of data and implementation cost. Each of these factors addresses a specific area that customers pay close attention to during the adoption process of a cloud BI solution. Offering ubiquitous access to date and respsonsive answers to customer requests are particularly emphasized for SMEs. We also found that industry tailored software is preferred, monthly or quarterly billings, and contact by email or phone for service. The paper shows recommendations, implications of research and suggests further research on the topic.</p>
  • Ahankoob, Alireza, et al. (författare)
  • The role of contractors’ building information modelling (BIM) experience in realising the potential values of BIM
  • 2019
  • Ingår i: International Journal of Construction Management. - Abingdon : Taylor & Francis. - 1562-3599 .- 2331-2327.
  • Tidskriftsartikel (refereegranskat)abstract
    • <p>There has been recently a growing attention towards the potential benefits of building informa- tion modelling (BIM) in construction business processes from both academia and industry practi- tioners. While prior research has emphasised that there is a link between the proficiency of construction companies to use BIM and the realisation of BIM benefits, little evidence exists to capture this relationship. The aim of this study is to explore the extent to which prior BIM expe- riences influence the perception of industry experts on potential BIM benefits. The influence of years of BIM experience on the discernment of BIM potential benefits was examined through a survey of Australian building contractors. The results of the analysis of variance (ANOVA) showed that BIM experience was a significant factor in the realisation of potential BIM benefits. The results suggest that an increase in years of BIM experience foster a better understanding of BIM benefits, which consequently can lead to a more inspiring movement towards the adoption of BIM by construction organisations. The main contribution of this article is to increase awareness towards the adoption and implementation of BIM by making a link between BIM proficiency and an increased perception of BIM potential benefits in construction organisations. © 2019 Informa UK Limited, trading as Taylor &amp; Francis Group.</p>
  • Ahlborg, Mikael, 1985-, et al. (författare)
  • Into the realm of social capital for adolescents A latent profile analysis
  • 2019
  • Ingår i: PLoS ONE. - San Francisco, CA : Public Library of Science. - 1932-6203. ; 14:2
  • Tidskriftsartikel (refereegranskat)abstract
    • <p>Background</p><p>Recent reports of increasing prevalence of frequent health complaints and mental health problems among adolescents call for directing more attention on determinants of adolescent health. The relationship between health and social capital has gained increased attention since the early 2000’s and research at review level confirms the importance of social capital for health outcomes, despite methodological heterogeneity. The aim of this study was to identify distinct profiles of family, school and peer social capital in a nationally representative sample of adolescents and to explore health outcomes in those profiles.</p><p>Method</p><p>Cross-sectional data from the Swedish Health Behaviour of School-aged Children 2013/14 was used for this study. The analytical sample consisted of 7,804 adolescents aged 11-, 13- and 15-years. Items representing sense of belonging and emotional support were assessed in three contexts; family, school and among peers. Latent profile analyses (LPA) were run to determine social capital profiles. Health outcomes included frequent health complaints and life satisfaction, while socioeconomic status and genders were included as predictors.</p><p>Results</p><p>The results show that five distinct profiles best represent the data for 11- and 15-year olds, while a four-profile model was optimal for 13-year olds. Some profiles were recurrent between age groups but unique profiles were also found. Health outcomes were significantly different between profiles depending on levels of social capital in the different contexts.</p><p>Conclusions</p><p>This study provides novel insight into how social capital co-occurs among adolescents within the contexts of family, school and peers and how this translates into differences in health outcomes. The national representativeness of the sample increases the implications of the results and contributes to meaningful insights that help explain the interactions of social capital in multiple contexts, complementing what is previously known about the relationship with adolescent health. © 2019 Ahlborg et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.</p>
  • Ahlborg, Mikael, 1985-, et al. (författare)
  • Socioeconomic inequalities in health among Swedish adolescents - adding the subjective perspective
  • 2017
  • Ingår i: BMC Public Health. - London : BioMed Central. - 1471-2458 .- 1471-2458. ; 17
  • Tidskriftsartikel (refereegranskat)abstract
    • <p>Background</p><p>Socioeconomic inequalities in adolescent health predict future inequalities in adult health. Subjective measures of socioeconomic status (SES) may contribute with an increased understanding of these inequalities. The aim of this study was to investigate socioeconomic health inequalities using both a subjective and an objective measure of SES among Swedish adolescents.</p><p>Method</p><p>Cross-sectional HBSC-data from 2002 to 2014 was used with a total sample of 23,088 adolescents aged 11–15 years. Three measures of self-rated health (dependent variables) were assessed: multiple health complaints, life satisfaction and health perception. SES was measured objectively by the Family Affluence Scale (FAS) and subjectively by “perceived family wealth” (independent variables). The trend for health inequalities was investigated descriptively with independent t-tests and the relationship between independent and dependent variables was investigated with multiple logistic regression analysis. Gender, age and survey year was considered as possible confounders.</p><p>Results</p><p>Subjective SES was more strongly related to health outcomes than the objective measure (FAS). Also, the relation between FAS and health was weakened and even reversed (for multiple health complaints) when subjective SES was tested simultaneously in regression models (FAS OR: 1.03, CI: 1.00;1.06 and subjective SES OR: 0.66, CI: 0.63;0.68).</p><p>Conclusions</p><p>The level of socioeconomic inequalities in adolescent health varied depending on which measure that was used to define SES. When focusing on adolescents, the subjective appraisals of SES is important to consider because they seem to provide a stronger tool for identifying inequalities in health for this group. This finding is important for policy makers to consider given the persistence of health inequalities in Sweden and other high-income countries. ©  The Author(s). 2017</p>
Skapa referenser, mejla, bekava och länka
fritt online (1730)
Typ av publikation
tidskriftsartikel (3434)
konferensbidrag (2738)
bokkapitel (830)
rapport (356)
doktorsavhandling (198)
annan publikation (187)
visa fler...
bok (127)
licentiatavhandling (84)
recension (84)
samlingsverk (redaktörskap) (71)
proceedings (redaktörskap) (51)
forskningsöversikt (41)
patent (31)
konstnärligt arbete (8)
visa färre...
Typ av innehåll
refereegranskat (6244)
övrigt vetenskapligt (5151)
populärvet., debatt m.m. (392)
Vinel, Alexey, 1983- ... (193)
Stambulova, Natalia, ... (160)
Svensson, Göran, 196 ... (150)
Fridlund, Bengt, (147)
Jonsson, Magnus, 196 ... (137)
Bergman, Stefan, 195 ... (127)
visa fler...
Solberg Søilen, Klau ... (113)
Johnson, Urban, 1961 ... (112)
Bremander, Ann, 1957 ... (110)
Andersson, Svante, 1 ... (109)
Svedberg, Petra, 197 ... (109)
Iagnemma, Karl, (96)
Ivarsson, Andreas, 1 ... (92)
Bacauskiene, Marija, (86)
Verikas, Antanas, (84)
Gabrielsson, Jonas, ... (79)
Nilsson, Pernilla, 1 ... (78)
Pettersson, Håkan, 1 ... (72)
Bååth, L.B., 1948-, (71)
Rosen, Bengt-Göran, ... (71)
Skärsäter, Ingela, 1 ... (70)
Gelzinis, Adas, (69)
Bigun, Josef, 1961-, (67)
Karlsson, Staffan, 1 ... (66)
Jormfeldt, Henrika, ... (65)
Taha, Walid, 1971-, (64)
Svensson, Göran, (62)
Erlandsson, Lena-Kar ... (62)
Stambulova, Natalia (62)
Verikas, Antanas, 19 ... (59)
Berg, Martin, 1977-, (58)
Ziegert, Kristina, 1 ... (57)
Werner, Sven, 1952-, (57)
Rosén, Bengt-Göran, (55)
Tideman, Magnus, 195 ... (55)
Mousavi, Mohammad Re ... (54)
Larsson, Ingrid, 196 ... (54)
Nowaczyk, Sławomir, ... (54)
Fridlund, Bengt, 195 ... (53)
Bigun, Josef, (52)
Samuelson, Lars, (49)
Wood, Greg, (49)
Haglund, Emma, 1970- ... (45)
Svensson, Bertil, (45)
Arvidsson, Barbro, (45)
Åkesson, Maria, 1963 ... (44)
Nygren, Jens M., 197 ... (43)
Lindwall, Magnus, 19 ... (43)
Carlsson, Ing-Marie, ... (43)
Jonasson, Mikael, 19 ... (43)
visa färre...
Högskolan i Halmstad (8232)
Engelska (6783)
Svenska (1293)
Tyska (45)
Spanska (23)
Norska (10)
Danska (8)
visa fler...
Bulgariska (7)
Ukrainska (6)
Kinesiska (3)
Franska (2)
Portugisiska (2)
Ryska (1)
Finska (1)
Nederländska (1)
Turkiska (1)
visa färre...
Forskningsämne (UKÄ/SCB)
Samhällsvetenskap (3213)
Teknik (1864)
Medicin och hälsovetenskap (1609)
Naturvetenskap (1233)
Humaniora (539)
Lantbruksvetenskap (25)


pil uppåt Stäng

Kopiera och spara länken för att återkomma till aktuell vy