| 51. |
- Abdalla, Suliman A
(författare)
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Architecture and circuit design of photon counting readout for X-ray imaging sensors
- 2007
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Hybrid pixel array detectors for X-ray imaging are based on different technologies for sensor and readout electronics. The readout electronics are based on standard CMOS technologies that are experiencing continuously rapid improvements by means of down-scaling the feature sizes, which in turn lead to higher transistor densities, lower power consumption, and faster circuits. For pixel-array imaging sensors the improvements in CMOS technology opens up new possibilities of integrating more functionality in the pixels for local processing of the sensor data. However, new issues related to the tight integration of both analog and digital processing circuits within the small area of a pixel must also be evaluated. The advantages of down-scaling the CMOS technology can be utilized to increase the spatial resolution by reducing the pixel sizes. Recent research indicates however that the bottleneck in reaching further spatial resolution in X-ray imaging sensors may not be limited by the circuit area occupied by the functions necessary in the pixels, but are instead related to problems associated with charge-sharing of charges generated by the sensor which are distributed over a neighbourhood of pixels and will limit the spatial resolution and lead to a distortion of the energy spectrum. In this thesis a mechanism to be implemented in the readout circuits is proposed in order to suppress the charge-sharing effects. The proposed architecture and its circuit implementation are evaluated with respect to circuit complexity (area) and power consumption. For a photon-counting pixel it is demonstrated that the complete pixel, with charge-sharing suppression mechanism, can be implemented using 300 transistors with an idle power consumption of 2.7μW in a 120nm CMOS technology operating with a 1.2V power supply. The improvements in CMOS technology can also be used for increasing the range of applications for X-ray imaging sensors. In this thesis, an architecture is proposed for multiple energy discrimination, called color X-ray imaging. The proposed solution is the result of balancing the circuit complexity and the image quality. The method is based on color sub-sampling with intensity biasing. For three-level energy discrimination, that corresponds to color imaging systems for visible light with R, G, and B color components, the increase in circuit complexity will be only 20% higher than that for the Bayer method but results in significantly better image quality. As the circuit complexity in the digital processing within each pixel is increased, the digitally induced noise may play an increasingly important role for the signal-to-noise ratio in the measurements. In this thesis an initial study is conducted regarding how the digital switching noise affects the analog amplifiers in the photon-counting pixel.
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| 52. |
- Abdalla, Suliman, et al.
(författare)
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Architecture and Circuit Design for Color X-Ray Pixal Array Detector Read-Out Electronics
- 2007
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Ingår i: 24th Norchip Conference, 2006. - New York : IEEE conference proceedings. - 9781424407729 ; , s. 271-276
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Konferensbidrag (refereegranskat)abstract
- This paper proposes an area- and power-efficient implementation of the read-out electronics for color X-ray pixel detectors for imaging. Introducing multiple levels of energy discrimination will increase the complexity of the read-out electronics in each pixel. The proposed architecture has full resolution for the intensity and reduced resolution for the energy spectrum (color), which leads to a good compromise of image quality and circuit complexity. We show that the increase in complexity, compared to single energy-range pixel, will lead to increase in circuit area of less than 20%.
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| 53. |
- Abdalla, Suliman, et al.
(författare)
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Circuit Implementation of Mechanism for Charge-Sharing Suppression for Photon-Counting Pixel Arrays
- 2005
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Ingår i: 23rd NORCHIP Conference 2005. - : IEEE conference proceedings. - 1424400643 ; , s. 137-140
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Konferensbidrag (refereegranskat)abstract
- This work proposes an efficient circuit implementation of a mechanism for charge-sharing suppression in photon-counting pixel arrays based on current-mode circuits for the analog parts. The additional circuits needed for charge-sharing suppression in a four-pixel cluster, leads to an increase in power consumption of 36% and only a marginal increase in circuit area. The implemented pixel with window-discrimination, managing charge-sharing in a four-pixel cluster and with an event-counter of 13 bits, consists of 300 transistors and has a power consumption of 2.7 μW when idle. It is implemented in a 120nm CMOS process and the presented results are based on simulations.
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| 54. |
- Abdipour, Morteza, et al.
(författare)
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A Design Research Lab—An Integrated Model to Identify Conscious and Unconscious Behavior in the Design Process
- 2016
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Ingår i: Advances in Design for Inclusion. - Cham : Springer. - 9783319419619 - 9783319419626
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Konferensbidrag (refereegranskat)abstract
- To understand how different design solutions affect users, designers traditionally use different evaluation methods that mainly rely on conscious feedback from the users. However, the complexity of human behaviour, where a large part is unconscious, point to a need for an extended tool box addressing the part not accessible to human conscious knowledge. Here, we describe a design research lab where traditional methods are complemented with tools to measure physiological signals influenced by emotional and sympathetic responses. These tools include galvanic skin response (GSR), electrocardiograph (ECG), and electroencephalograph (EEG). Typical sessions with acquired data of conscious and unconscious user reactions are described. The large body of data collected, which also require non-design expertise for interpretation, suggest that a further development towards simplified output data of the unconscious reactions is needed to allow wider use within industrial design work.
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| 55. |
- Abdul Djalil, Muslim, et al.
(författare)
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The importance of entrepreneurial leadership in fostering bank performance
- 2023
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Ingår i: International Journal of Bank Marketing. - 0265-2323 .- 1758-5937. ; 41:4, s. 926-948
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Tidskriftsartikel (refereegranskat)abstract
- Purpose – This study investigates how entrepreneurial leadership fosters market orientation, bankinnovativeness and bank performance; it also investigates how market orientation contributes to brandorientation, bank innovativeness and bank performance.Design/methodology/approach – In total, 1500 questionnaires were distributed to 100 bank branches inIndonesia (500 to managers and 1000 to employees); 300 responses (20% response rate) were used for furtherstatistical analysis.Findings – The results confirmed the existence of relationships among entrepreneurial leadership, marketorientation, bank innovativeness, brand orientation and bank performance. The role of entrepreneurialleadership in fostering market orientation, bank innovativeness, brand orientation and bank performancedemonstrates that leaders can motivate employees to complete their tasks.Practical implications – The findings suggest that entrepreneurial leadership, new ideas and innovativeproducts and services can foster bankperformance.Originality/value – The emerging banking industry in Indonesia has witnessed changing market conditions.Banks will benefit from being more market-driven and diverse in their customer relationships togenerate value.
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| 56. |
- Abdul Waheed, Malik, 1981-, et al.
(författare)
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Generalized Architecture for a Real-time Computation of an Image Component Features on a FPGA
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- This paper describes a generalized architecture for real-time component labeling and computation of image component features. Computing real-time image component features is one of the most important paradigms for modern machine vision systems. Embedded machine vision systems demand robust performance, power efficiency as well as minimum area utilization. The presented architecture can easily be extended with additional modules for parallel computation of arbitrary image component features. Hardware modules for component labeling and feature calculation run in parallel. This modularization makes the architecture suitable for design automation. Our architecture is capable of processing 390 video frames per second of size 640x480 pixels. Dynamic power consumption is 24.20mW at 86 frames per second on a Xilinx Spartran6 FPGA.
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| 57. |
- Abdulgadir, Alamin, et al.
(författare)
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Performance Simulation of a Composite Filter Material Containing Mechanical Pulp Fibers, Microfibrillated Cellulose, and Cellulose Nanofibers
- 2022
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Ingår i: Proceedings of the International Mechanical Pulping Conference. ; , s. 160-
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Nonwoven fibrous materials with reticular support of an interconnected fiber network and a tortuous airflow pathway have been commonly used in filtration applications. To meet the criteria of filter efficiency and performance, the filter materials are recommended to contain different types of fibers such as mechanical pulp fibers, microfibrillated cellulose, cellulose nanofibers, and other polymer or synthetic fibers with a range of dimensions, i.e., length and diameter. Cellulose fibers in filter media possess irregular and complex structures with hollow or collapsed lumen structures owing to their refinement or pulping method. The development of an appropriate filter media model requires information on actual fiber characteristics. In this study, a simulation method was used to investigate the complex microstructures of filter media. The physical parameters such as fiber wall thickness, diameter, length, cross-section shapes, and curliness were obtained from fiber analyzers and scanning electron microscopy. Based on the experimental findings, GeoDict database comprising different types of common fiber models was constructed. 3-Dimensional fibrous models corresponding to the wet-laid binderless filter material were generated. Using the GeoDict modules, the pore size distributions, average pore sizes, air permeability, pressure drop and initial filter efficiency simulations were performed. The simulation results appear to be in close agreement with the experimental results. The incorporation of cellulose nanofibers resulted in reduced average pore sizes and air permeability of the filter material, thus enhancing the initial filter efficiency. The filter media developed a biobased material derived from pulp fibers for advanced applications such as medical facemask, and air filtration purposes.
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| 58. |
- Abdullah, Abu Sayeed Md., et al.
(författare)
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Effects of climate change and maternal morality : Perspective from case studies in the rural area of Bangladesh
- 2019
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Ingår i: International Journal of Environmental Research and Public Health. - : MDPI AG. - 1661-7827 .- 1660-4601. ; 16:23
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Tidskriftsartikel (refereegranskat)abstract
- This study explored the community perception of maternal deaths influenced by natural disaster (flood), and the practice of maternal complications during natural disaster among the rural population in Bangladesh. It also explored the challenges faced by the community for providing healthcare and referring the pregnant women experiencing complications during flood disaster. Three focus group discussions (FGDs) and eight in-depth interviews (IDIs) were conducted in the marginalized rural communities in the flood-prone Khaliajhuri sub-district, Netrakona district, Bangladesh. Flood is one of the major risk factors for influencing maternal death. Pregnant women seriously suffer from maternal complications, lack of antenatal checkup, and lack of doctors during flooding. During the time of delivery, it is difficult to find a skilled attendant, and referring the patient with delivery complications to the healthcare facility. Boats are the only mode of transport. The majority of maternal deaths occur on the boats during transfer from the community to the hospital. Rural people feel that the maternal deaths influenced by natural disaster are natural phenomena. Pre-preparation is needed to support pregnant women during disasters. There is unawareness of maternal health, related care, and complications during disasters among local health service providers and volunteers.
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| 59. |
- Abdullah, Abu Sayeed Md., et al.
(författare)
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Perceptions and practices on newborn care and managing complications at rural communities in Bangladesh : a qualitative study
- 2021
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Ingår i: BMC Pediatrics. - : Springer Nature. - 1471-2431. ; 21
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Tidskriftsartikel (refereegranskat)abstract
- Background: Community misperception on newborn care and poor treatment of sick newborn attributes to neonatal death and illness severity. Misperceptions and malpractices regarding neonatal care and neonatal complications are the leading causes of neonatal deaths in Bangladesh. The study was conducted to explore neonatal care’s perceptions and practices and manage complications among Bangladesh’s rural communities.Methods: A qualitative study was conducted in Netrakona district of Bangladesh from April to June 2015. Three sub-districts (Upazilas) including Purbadhala, Durgapur and Atpara of Netrakona district were selected purposively. Five focus group discussions (FGDs) and twenty in-depth interviews (IDIs) were conducted in the rural community. Themes were identified through reading and re-reading the qualitative data and thematic analysis was performed.Results: Community people were far behind, regarding the knowledge of neonatal complications. Most of them felt that the complications occurred due to lack of care by the parents. Some believed that mothers did not follow the religious customs after delivery, which affected the newborns. Many of them followed the practice of bathing the newborns and cutting their hair immediately after birth. The community still preferred to receive traditional treatment from their community, usually from Kabiraj (traditional healer), village doctor, or traditional birth attendant. Families also refrained from seeking treatment from the health facilities during neonatal complications. Instead, they preferred to wait until the traditional healers or village doctors recommended transferring the newborn.Conclusions: Poor knowledge, beliefs and practices are the key barriers to ensure the quality of care for the newborns during complications. The communities still depend on traditional practices and the level of demand for facility care is low. Appropriate interventions focusing on these issues might improve the overall neonatal mortality in Bangladesh.
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| 60. |
- Abedi, Tooba, et al.
(författare)
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Optimal rotation age of Populus deltoides considering economic value of timber harvesting and carbon sequestration
- 2018
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Ingår i: Austrian Journal of Forest Science. - 0379-5292. ; 135:4, s. 315-342
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this research is to determine the optimal rotation age of Populus deltoides plantations regarding to the timber and carbon sequestration values in the north of Iran. Two plantation types with a tree density of 3 by 3 m and of 3 by 4 m were considered in Choobar forest, northern Iran. Net present value (NPV) of timber and carbon were used for determining the optimal rotation age. Data on volume increment, carbon content, revenue, timber and carbon prices were collected to estimate NPV. In this study, we considered the effects of different plantation cost, land value and discount rates on the optimal rotation ages. Our results indicated, if economic value of timber is considered, optimal rotation ages were 10 and 8 years for 3 by 3 m and 3 by 4 m density, respectively. Optimal rotation ages considering carbon sequestration, in addition to timber value, increased to 14 and 11 years for the same two densities, respectively. Thus, integrating carbon sequestration value with timber economic value increased the optimal rotation ages and in turn change the optimal forest management. Sensitivity analysis indicate that optimal rotation ages increased with increasing plantation cost and decreased with increasing interest rate, while our results suggested that the optimal rotation age is not sensitive to the land value. Our results are important for land managers and carbon projects to optimize the used forest management practices.
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