| 1. |
- Akbari, Saeed, et al.
(författare)
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Ceramic Additive Manufacturing Potential for Power Electronics Packaging
- 2022
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Ingår i: IEEE Transactions on Components, Packaging, and Manufacturing Technology. - : Institute of Electrical and Electronics Engineers Inc.. - 2156-3950 .- 2156-3985. ; 12:11, s. 1857-1866
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Tidskriftsartikel (refereegranskat)abstract
- Compared with silicon-based power devices, wide band gap (WBG) semiconductor devices operate at significantly higher power densities required in applications such as electric vehicles and more electric airplanes. This necessitates development of power electronics packages with enhanced thermal characteristics that fulfil the electrical insulation requirements. The present research investigates the feasibility of using ceramic additive manufacturing (AM), also known as three-dimensional (3D) printing, to address thermal and electrical requirements in packaging gallium nitride (GaN) based high-electron-mobility transistors (HEMTs). The goal is to exploit design freedom and manufacturing flexibility provided by ceramic AM to fabricate power device packages with a lower junction-to-ambient thermal resistance (RθJA). Ceramic AM also enables incorporation of intricate 3D features into the package structure in order to control the isolation distance between the package source and drain contact pads. Moreover, AM allows to fabricate different parts of the packaging assembly as a single structure to avoid high thermal resistance interfaces. For example, the ceramic package and the ceramic heatsink can be printed as a single part without any bonding layer. Thermal simulations under different thermal loading and cooling conditions show the improvement of thermal performance of the package fabricated by ceramic AM. If assisted by an efficient cooling strategy, the proposed package has the potential to reduce RθJA by up to 48%. The results of the preliminary efforts to fabricate the ceramic package by AM are presented, and the challenges that have to be overcome for further development of this manufacturing method are recognized and discussed.
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| 2. |
- Akbari, Saeed, et al.
(författare)
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Large-Scale Robot-Based Polymer and Composite Additive Manufacturing : Failure Modes and Thermal Simulation
- 2022
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Ingår i: Polymers. - : MDPI. - 2073-4360. ; 14:9
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Tidskriftsartikel (refereegranskat)abstract
- Additive manufacturing (AM) of large-scale polymer and composite parts using robotic arms integrated with extruders has received significant attention in recent years. Despite the contributions of great technical progress and material development towards optimizing this manufacturing method, different failure modes observed in the final printed products have hindered its application in producing large engineering structures used in aerospace and automotive industries. We report failure modes in a variety of printed polymer and composite parts, including fuel tanks and car bumpers. Delamination and warpage observed in these parts originate mostly from thermal gradients and residual stresses accumulated during material deposition and cooling. Because printing large structures requires expensive resources, process simulation to recognize the possible failure modes can significantly lower the manufacturing cost. In this regard, accurate prediction of temperature distribution using thermal simulations is the first step. Finite element analysis (FEA) was used for process simulation of large-scale robotic AM. The important steps of the simulation are presented, and the challenges related to the modeling are recognized and discussed in detail. The numerical results showed reasonable agreement with the temperature data measured by an infrared camera. While in small-scale extrusion AM, the cooling time to the glassy state is less than 1 s, in large-scale AM, the cooling time is around two orders of magnitudes longer. © 2022 by the authors
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| 3. |
- Akbari, Saeed, et al.
(författare)
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Low Inductive SiC Power Electronics Module with Flexible PCB Interconnections and 3D Printed Casing
- 2022
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Ingår i: 2022 IMAPS Nordic Conference on Microelectronics Packaging, NordPac 2022. - : Institute of Electrical and Electronics Engineers Inc.. - 9789189711396
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Konferensbidrag (refereegranskat)abstract
- Silicon carbide (SiC) power devices are steadily increasing their market share in various power electronics applications. However, they require low-inductive packaging in order to realize their full potential. In this research, low-inductive layouts for half-bridge power modules, using a direct bonded copper (DBC) substrate, that are suitable for SiC power devices, were designed and tested. To reduce the negative effects of the switching transients on the gate voltage, flexible printed circuit boards (PCBs) were used to interconnect the gate and source pins of the module with the corresponding pads of the power chips. In addition, conductive springs were used as low inductive, solder-free contacts for the module power terminals. The module casing and lid were produced using additive manufacturing, also known as 3D printing, to create a compact design. It is shown that the inductance of this module is significantly lower than the commercially available modules.
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| 4. |
- Akbari, Saeed, et al.
(författare)
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Multimaterial 3D Printed Soft Actuators Powered by Shape Memory Alloy Wires
- 2019
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Ingår i: Sensors and Actuators A-Physical. - : Elsevier BV. - 0924-4247 .- 1873-3069. ; 290, s. 177-189
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Tidskriftsartikel (refereegranskat)abstract
- Shape memory alloys (SMAs) have been widely used to fabricate soft actuators by embedding SMA wires into various soft matrices manufactured by conventional moulding methods or novel three-dimensional (3D) printing techniques. However, soft matrices of SMA based actuators are typically fabricated from only one or two different materials. Here, we exploit the great manufacturing flexibility of multimaterial 3D printing to fabricate various bending, twisting and extensional actuators by precisely controlling the spatial arrangements of different printing materials with different stiffnesses. In order to achieve a broad range of deformations, ten different printing materials were characterized and used in the actuators design. In addition, we developed a finite element model to simulate complex deformations of the printed actuators and facilitate the design process. The model incorporates a user defined material subroutine that describes the nonlinear temperature dependant behavior of SMAs. The results show the efficiency and flexibility of multimaterial 3D printing in tailoring the deformed shape of the SMA based soft actuators, which cannot be accomplished using conventional manufacturing methods such as moulding.
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| 5. |
- Akbari, Saeed, et al.
(författare)
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Packaging Induced Stresses in Embedded and Molded GaN Power Electronics Components
- 2023
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Ingår i: Int. Conf. Therm., Mech. Multi-Phys. Simul. Exp. Microelectron. Microsyst., EuroSimE. - : Institute of Electrical and Electronics Engineers Inc..
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Konferensbidrag (refereegranskat)abstract
- Residual stresses created during the packaging process can adversely affect the reliability of electronics components. We used incremental hole-drilling method, following the ASTM E 837-20 standard, to measure packaging induced residual stresses in discrete packages of power electronics components. For this purpose, we bonded a strain gauge on the surface of a Gallium Nitride (GaN) power component, drilled a hole through the thickness of the component in several incremental steps, recorded the relaxed strain data on the sample surface using the strain gauge, and finally calculated the residual stresses from the measured strain data. The recorded strains and the residual stresses are related by the compliance coefficients. For the hole drilling method in the isotropic materials, the compliance coefficients are calculated from the analytical solutions, and available in the ASTM standard. But for the orthotropic multilayered components typically found in microelectronics assemblies, numerical solutions are necessary. We developed a subroutine in ANSYS APDL to calculate the compliance coefficients of the hole drilling test in the molded and embedded power electronics components. This can extend the capability of the hole drilling method to determine residual stresses in more complex layered structures found in electronics.
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| 6. |
- Akbari, Saeed, et al.
(författare)
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Shape memory alloy based 3D printed composite actuators with variable stiffness and large reversible deformation
- 2021
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Ingår i: Sensors and Actuators A-Physical. - : Elsevier B.V.. - 0924-4247 .- 1873-3069. ; 321
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Tidskriftsartikel (refereegranskat)abstract
- Soft composite actuators can be fabricated by embedding shape memory alloy (SMA) wires into soft polymer matrices. Shape retention and recovery of these actuators are typically achieved by incorporating shape memory polymer segments into the actuator structure. However, this requires complex manufacturing processes. This work uses multimaterial 3D printing to fabricate composite actuators with variable stiffness capable of shape retention and recovery. The hinges of the bending actuators presented here are printed from a soft elastomeric layer as well as a rigid shape memory polymer (SMP) layer. The SMA wires are embedded eccentrically over the entire length of the printed structure to provide the actuation bending force, while the resistive wires are embedded into the SMP layer of the hinges to change the temperature and the bending stiffness of the actuator hinges via Joule heating. The temperature of the embedded SMA wire and the printed SMP segments is changed sequentially to accomplish a large bending deformation, retention of the deformed shape, and recovery of the original shape, without applying any external mechanical force. The SMP layer thickness was varied to investigate its effect on shape retention and recovery. A nonlinear finite element model was used to predict the deformation of the actuators.
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| 7. |
- Akbari, Saeed, et al.
(författare)
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Shape-reversible 4D printing aided by shape memory alloys
- 2022
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Ingår i: Smart Materials in Additive Manufacturing, volume 2: 4D Printing Mechanics, Modeling, and Advanced Engineering Applications. - : Elsevier. - 9780323954303 - 9780323954310 ; , s. 387-406
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Four-dimensional (4D) printed structures fabricated from shape memory polymers (SMPs) are typically one-way actuators, that is, for each actuation cycle, they must be programmed to deform from the original (as-printed) shape to a secondary (programmed) shape. This is done by applying a combination of thermal and mechanical loads. Then, they restore the initial shape during the actuation process by applying a thermal load. Here, we generalize this concept to fabricate two-way actuators by embedding shape memory alloy (SMA) wires into the printed SMP structures. To explain this in greater detail, we describe the printing process of a two-way bending actuator whose bilayer hinges consist of stiff SMPs as well as elastomers with low modulus. Joule heating was employed to modulate the hinges bending stiffness. To this end, electrical current was applied to the resistive wires inserted into the hinges SMP layer to control their temperature. On the other hand, thermomechanical programming of the SMA wires, which were integrated into the actuator, provided the bending actuation force. The fabricated actuator was able to bend, maintain the deformed shape, and recover the as-fabricated shape in a fully automated manner. Further potentials of this design methodology were assessed using a nonlinear finite element model. The model incorporated user-defined subroutines to incorporate complex material behaviors of SMAs and SMPs.
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| 8. |
- Akbari-Zardkhaneh, Saeed, et al.
(författare)
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Five-Dimensional Personality Test: Development and Validation of a Persian Version
- 2018
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Ingår i: Psychological Studies. - : Springer. - 0033-2968 .- 0974-9861. ; 63:3, s. 219-227
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Tidskriftsartikel (refereegranskat)abstract
- Dimensional approach to personality disorders conceptualizes personality disorders quantitatively different from normal personality. Five-Dimensional Personality Test (5DPT; Coolidge et al. in Pers Individ Differ 44(6):1326–1334, 2008) provides an assessment based on this approach. The 5DPT holds considerable usefulness and potential for investigating personality, and this potential may be much better utilized through availability of abbreviated versions and culture-specific forms. This paper describes efforts to develop and validate a Persian form of 5DPT. Findings of the study showed that some items of the original form were not able to represent the theoretical factors. However, discarding these items did not affect the factor structure of the new measure. It was demonstrated that the Persian version is composed of five saturated factors (neuroticism, absorption, orderliness, extraversion, and insensitivity) fitted to the data. Also, the structural equivalence of the two forms was discussed. Since the final scale turned out to be more concise, consisting of 75 of the original 100 items, application of this measure in research and clinical settings is facilitated.
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| 9. |
- Bassani, Carlos L., et al.
(författare)
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Nanocrystal Assemblies : Current Advances and Open Problems
- 2024
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Ingår i: ACS Nano. - 1936-0851. ; 18:23, s. 14791-14840
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Forskningsöversikt (refereegranskat)abstract
- We explore the potential of nanocrystals (a term used equivalently to nanoparticles) as building blocks for nanomaterials, and the current advances and open challenges for fundamental science developments and applications. Nanocrystal assemblies are inherently multiscale, and the generation of revolutionary material properties requires a precise understanding of the relationship between structure and function, the former being determined by classical effects and the latter often by quantum effects. With an emphasis on theory and computation, we discuss challenges that hamper current assembly strategies and to what extent nanocrystal assemblies represent thermodynamic equilibrium or kinetically trapped metastable states. We also examine dynamic effects and optimization of assembly protocols. Finally, we discuss promising material functions and examples of their realization with nanocrystal assemblies.
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| 10. |
- Hosseini, S. M., et al.
(författare)
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Numerical and experimental studies of fabrication-induced thermal residual stresses in microelectronic packages
- 2021
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Ingår i: IEEE Transactions on Components, Packaging, and Manufacturing Technology. - : Institute of Electrical and Electronics Engineers Inc.. - 2156-3950 .- 2156-3985. ; 11:5, s. 755-764
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Tidskriftsartikel (refereegranskat)abstract
- Microelectronic packages are typically composed of different layers of materials with un-similar thermo-mechanical properties. Fabrication-induced residual stresses, resulting from the mismatch of layers’ thermo-mechanical properties, may lead to adverse effects such as warpage and delamination at the interface of layers. In this study, the fabrication process of the ball grid array (BGA) package was simulated to predict the thermal residual stresses through the thickness of the package. A finite element model incorporating realistic material behavior of the BGA package layers was developed. To this end, the epoxy molding compound (EMC) was modeled as a viscoelastic material, while the silicon chip, the die-attach, and the composite substrate were simulated using an elastic model during cooling. Since Young’s modulus of EMC is time and temperature-dependent, three different process temperatures were simulated to investigate the impact of viscoelastic properties of EMC, defined using Prony coefficients, on numerical residual stresses. To verify the simulation results, the incremental hole-drilling method was used to experimentally measure the residual stress components. It includes drilling a small hole at the center of a rosette strain gauge bonded on the BGA package surface and measuring the released strains on the surface. The relaxed strains were then converted to the residual stresses using a calibration matrix whose coefficients are determined from a finite element model. The reasonable agreement of numerical and experimental components of the residual stress throughout the thickness of the BGA package confirms the reliability of the proposed simulation approach in estimating residual stresses in microelectronics packages.
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| 11. |
- Hosseini, S. M., et al.
(författare)
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Residual stress measurement through the thickness of ball grid array microelectronics packages using incremental hole drilling
- 2019
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Ingår i: Microelectronics and reliability. - : Elsevier Ltd. - 0026-2714 .- 1872-941X. ; 102
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Tidskriftsartikel (refereegranskat)abstract
- Microelectronic packages typically consist of several layers of polymer, silicon, and composite materials, which are bonded together under heat and pressure. The mismatch in thermo-mechanical properties between different layers can induce significant residual stresses in the fabrication process that may lead to delamination at the interface between the bonded layers. Therefore, it is important to develop a reliable method to determine residual stresses. In this study, incremental hole drilling method was used to determine fabrication-induced residual stresses in a ball grid array (BGA) microelectronics package. First, a small hole was drilled in several steps at the center of a strain gauge rosette bonded to the surface of the BGA package. This released residual stresses trapped at each depth increment and deformed the component. The corresponding surface strains were measured in three directions using rosette gauges. Then, the residual stress was calculated based on the integral method, in which the measured strains are converted to the residual stresses using a calibration matrix whose elements are obtained from a finite element model. The three in-plane components of the residual stress through the thickness of different layers of a BGA package, including molding compound, silicon chip, die attach, and the composite substrate, were reported based on the incremental hole drilling method. These findings show that the incremental hole drilling method can be used as a reliable method to estimate the residual stresses over the entire thickness of microelectronic packages, and evaluate their effect on the reliability under service conditions.
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| 12. |
- Kormi-Nouri, Reza, 1954-, et al.
(författare)
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The effect of bilingualism on letter and category fluency tasks in primary school children : advantage or disadvantage?
- 2012
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Ingår i: Bilingualism. - : Cambridge University Press. - 1366-7289 .- 1469-1841. ; 15:2, s. 351-364
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Tidskriftsartikel (refereegranskat)abstract
- The aim of the current study was to examine the effects of bilingualism on letter and category fluency tasks. Participants were 1,600 monolingual and bilingual children from three cities in Iran: Tehran (Persian monolinguals), Tabriz (Turkish–Persian bilinguals), and Sanandaj (Kurdish–Persian bilinguals). We separately presented nine Persian letters and thirty-one categories to the participants, and asked them to generate as many words as possible using each of these initial letters and categories within a maximum of three minutes. Bilingual children generated more words than monolingual children in the letter fluency task; this effect was more pronounced in Grade 1 and for Turkish–Persian bilinguals. However, Persian monolinguals generated significantly more words than both bilingual groups in the category fluency task. Thus, bilingualism can be of both advantage and disadvantage, and produce a dissociative effect. We discuss the results on the basis of the specific nature and different cognitive demands of letter and category fluency tasks. We suggest that the degree of language proficiency of bilinguals should be considered as an important variable in future research on bilingualism.
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| 13. |
- Kormi-Nouri, Reza, 1954-, et al.
(författare)
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The effect of childhood bilingualism on episodic and semantic memory tasks
- 2008
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Ingår i: Scandinavian Journal of Psychology. - : Wiley. - 0036-5564 .- 1467-9450. ; 49:2, s. 93-109
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Tidskriftsartikel (refereegranskat)abstract
- Kormi-Nouri, Moniri and Nilsson (2003) demonstrated that Swedish-Persian bilingual children recalled at a higher level than Swedish monolingual children, when they were tested using Swedish materials. The present study was designed to examine the bilingual advantage of children who use different languages in their everyday life but have the same cultural background and live in their communities in the same way as monolingual children. In four experiments, 488 monolingual and bilingual children were compared with regard to episodic and semantic memory tasks. In experiments 1 and 2 there were 144 boys and 144 girls in three school groups (aged 9-10 years, 13-14 years and 16-17 years) and in three language groups (Persian monolingual, Turkish-Persian bilingual, and Kurdish-Persian bilingual). In experiments 3 and 4, there were 200 male students in two school groups (aged 9-10 years and 16-17 years) and in two language groups (Persian monolingual and Turkish-Persian bilingual). In the episodic memory task, children learned sentences (experiments 1-3) and words (Experiment 4). Letter and category fluency tests were used as measures of semantic memory. To change cognitive demands in memory tasks, in Experiment 1, the integration of nouns and verbs within sentences was manipulated by the level of association between verb and noun in each sentence. At retrieval, a recognition test was used. In experiments 2 and 3, the organization between sentences was manipulated at encoding in Experiment 2 and at both encoding and retrieval in Experiment 3 through the use of categories among the objects. At retrieval, free recall or cued recall tests were employed. In Experiment 4, the bilingual children were tested with regard to both their first and their second language. In all four experiments, a positive effect of bilingualism was found on episodic and semantic memory tasks; the effect was more pronounced for older than younger children. The bilingual advantage was not affected by changing cognitive demands or by using first/second language in memory tasks. The present findings support the cross-language interactivity hypothesis of bilingual advantage.
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| 14. |
- Lövberg, Andreas, et al.
(författare)
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On the formation and propagation of laminate cracks and their influence on the fatigue lives of solder joints
- 2018
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Ingår i: 2018 19th International Conference on Thermal, Mechanical and Multi-Physics Simulation and Experiments in Microelectronics and Microsystems, EuroSimE 2018. - 9781538623596 ; , s. 1-13
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Konferensbidrag (refereegranskat)abstract
- Lead-free solder joints have been shown to increase the risk for crack formation in the PCB laminate under the solder pads. As such cracks propagate during thermal cycling, they decrease the strain imposed on the solderjoint by acting as strain relief. In accelerated thermal cycling, these joints have been found to remain virtually undamaged even after a very high number of cycles. If these cracks do not form or propagate to the same extent under milder cycling conditions, typical of service conditions, it may lead to an overestimation of the fatigue life of the solder joints in accelerated testing. In this work, the extent of strain relief and the influence of grain orientations on the initiation and propagation of these cracks are investigated through FE-modelling and compared to what has been experimentally observed for cross-sections of solder joints moulded in epoxy resin with added fluorescent agent and inspected using UV-light and electron backscatter diffraction. Due to the strong anisotropy of lead-free solder joints, the stress transferred to the laminate will vary significantly depending on grain orientation. The presence of these laminate cracks adds another layer of uncertainty to the already complex SnAgCu system, where the strong effects of anisotropy, the continuously evolving secondary precipitate coarsening and its interaction with the recrystallisation process govern the damage evolution. If these effects are not properly accounted for, the interpretation of thermal cycling or modelling and simulation results may be strongly misleading.
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| 15. |
- Murray, Christopher J. L., et al.
(författare)
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Population and fertility by age and sex for 195 countries and territories, 1950–2017: a systematic analysis for the Global Burden of Disease Study 2017
- 2018
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Ingår i: The Lancet. - 1474-547X .- 0140-6736. ; 392:10159, s. 1995-2051
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Tidskriftsartikel (refereegranskat)abstract
- Background: Population estimates underpin demographic and epidemiological research and are used to track progress on numerous international indicators of health and development. To date, internationally available estimates of population and fertility, although useful, have not been produced with transparent and replicable methods and do not use standardised estimates of mortality. We present single-calendar year and single-year of age estimates of fertility and population by sex with standardised and replicable methods. Methods: We estimated population in 195 locations by single year of age and single calendar year from 1950 to 2017 with standardised and replicable methods. We based the estimates on the demographic balancing equation, with inputs of fertility, mortality, population, and migration data. Fertility data came from 7817 location-years of vital registration data, 429 surveys reporting complete birth histories, and 977 surveys and censuses reporting summary birth histories. We estimated age-specific fertility rates (ASFRs; the annual number of livebirths to women of a specified age group per 1000 women in that age group) by use of spatiotemporal Gaussian process regression and used the ASFRs to estimate total fertility rates (TFRs; the average number of children a woman would bear if she survived through the end of the reproductive age span [age 10–54 years] and experienced at each age a particular set of ASFRs observed in the year of interest). Because of sparse data, fertility at ages 10–14 years and 50–54 years was estimated from data on fertility in women aged 15–19 years and 45–49 years, through use of linear regression. Age-specific mortality data came from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2017 estimates. Data on population came from 1257 censuses and 761 population registry location-years and were adjusted for underenumeration and age misreporting with standard demographic methods. Migration was estimated with the GBD Bayesian demographic balancing model, after incorporating information about refugee migration into the model prior. Final population estimates used the cohort-component method of population projection, with inputs of fertility, mortality, and migration data. Population uncertainty was estimated by use of out-of-sample predictive validity testing. With these data, we estimated the trends in population by age and sex and in fertility by age between 1950 and 2017 in 195 countries and territories. Findings: From 1950 to 2017, TFRs decreased by 49·4% (95% uncertainty interval [UI] 46·4–52·0). The TFR decreased from 4·7 livebirths (4·5–4·9) to 2·4 livebirths (2·2–2·5), and the ASFR of mothers aged 10–19 years decreased from 37 livebirths (34–40) to 22 livebirths (19–24) per 1000 women. Despite reductions in the TFR, the global population has been increasing by an average of 83·8 million people per year since 1985. The global population increased by 197·2% (193·3–200·8) since 1950, from 2·6 billion (2·5–2·6) to 7·6 billion (7·4–7·9) people in 2017; much of this increase was in the proportion of the global population in south Asia and sub-Saharan Africa. The global annual rate of population growth increased between 1950 and 1964, when it peaked at 2·0%; this rate then remained nearly constant until 1970 and then decreased to 1·1% in 2017. Population growth rates in the southeast Asia, east Asia, and Oceania GBD super-region decreased from 2·5% in 1963 to 0·7% in 2017, whereas in sub-Saharan Africa, population growth rates were almost at the highest reported levels ever in 2017, when they were at 2·7%. The global average age increased from 26·6 years in 1950 to 32·1 years in 2017, and the proportion of the population that is of working age (age 15–64 years) increased from 59·9% to 65·3%. At the national level, the TFR decreased in all countries and territories between 1950 and 2017; in 2017, TFRs ranged from a low of 1·0 livebirths (95% UI 0·9–1·2) in Cyprus to a high of 7·1 livebirths (6·8–7·4) in Niger. The TFR under age 25 years (TFU25; number of livebirths expected by age 25 years for a hypothetical woman who survived the age group and was exposed to current ASFRs) in 2017 ranged from 0·08 livebirths (0·07–0·09) in South Korea to 2·4 livebirths (2·2–2·6) in Niger, and the TFR over age 30 years (TFO30; number of livebirths expected for a hypothetical woman ageing from 30 to 54 years who survived the age group and was exposed to current ASFRs) ranged from a low of 0·3 livebirths (0·3–0·4) in Puerto Rico to a high of 3·1 livebirths (3·0–3·2) in Niger. TFO30 was higher than TFU25 in 145 countries and territories in 2017. 33 countries had a negative population growth rate from 2010 to 2017, most of which were located in central, eastern, and western Europe, whereas population growth rates of more than 2·0% were seen in 33 of 46 countries in sub-Saharan Africa. In 2017, less than 65% of the national population was of working age in 12 of 34 high-income countries, and less than 50% of the national population was of working age in Mali, Chad, and Niger. Interpretation: Population trends create demographic dividends and headwinds (ie, economic benefits and detriments) that affect national economies and determine national planning needs. Although TFRs are decreasing, the global population continues to grow as mortality declines, with diverse patterns at the national level and across age groups. To our knowledge, this is the first study to provide transparent and replicable estimates of population and fertility, which can be used to inform decision making and to monitor progress. Funding: Bill & Melinda Gates Foundation.
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| 16. |
- Robert, Zhargalma Dandarova, et al.
(författare)
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A Web-based Database for Drawings of Gods: When the Digitals Go Multicultural
- 2016
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Ingår i: Archive for the Psychology of Religion/ Archiv für Religionspsychologie. - : Brill. - 0084-6724 .- 1573-6121. ; 38:3, s. 345-352
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Tidskriftsartikel (refereegranskat)abstract
- This original web-based database was developed at the University of Lausanne (Switzerland) as part of the international research project “Drawings of gods”, which explores children's representations of supernatural agents. Its primary purpose is to store and organize data and metadata to be easily accessible to all affiliated researchers. However, anyone interested in the matter can view the drawings, as they were made publicly available. At present, our corpus is composed of over 5'100 drawings collected in different parts of the world (i.e., Japan, Russia, Switzerland, Romania, USA and Iran) and yet constantly developing.
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| 17. |
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