| 831. |
- Keykhosravi, Kamran, 1990, et al.
(författare)
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When to Use Optical Amplification in Noncoherent Transmission: An Information-Theoretic Approach
- 2020
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Ingår i: IEEE Transactions on Communications. - 0090-6778 .- 1558-0857. ; 68:4, s. 2438-2445
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Tidskriftsartikel (refereegranskat)abstract
- The standard solution for short-haul fiber-optic communications is to deploy noncoherent systems, i.e., to modulate and detect only the light intensity. In such systems, the signal is corrupted with optical noise from amplifiers and with thermal (electrical) noise. The capacity of noncoherent optical links has been studied extensively in the presence of either optical noise or thermal noise. In this paper, for the first time, we characterize the capacity under an average power constraint with both noise sources by establishing upper and lower bounds. In the two extreme cases of zero optical noise or zero thermal noise, we assess our bounds against some well-known results in the literature; improvements in both cases are observed. Next, for amplified fiber-optic systems, we study the trade-off between boosting signal energy (mitigating the effects of thermal noise) and adding optical noise. For a wide spectrum of system parameters and received power levels, we determine the optimal amplification gain. While mostly either no amplification or high-gain amplification is optimal, the best performance is for some parameter intervals achieved at finite gains.
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| 832. |
- Khan, Fahd Ahmed, 1984, et al.
(författare)
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Electronic dispersion compensation by Hadamard transformation
- 2010
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Ingår i: Optical Fiber Communication Conference (OFC) - Proceedings. - Washington, D.C. : OSA. - 9781557528841 ; , s. paper OWV4-
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Konferensbidrag (refereegranskat)abstract
- We demonstrate that the Hadamard transform can be applied to look up table (LUT)-based predistorters to simultaneously compress and optimize the LUT for dispersion-limited links.
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| 833. |
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| 834. |
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| 835. |
- Kherad, Mehrsa, et al.
(författare)
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Risk factors for low back pain and sciatica in elderly men-the MrOS Sweden study
- 2017
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Ingår i: Age and Ageing. - : Oxford University Press (OUP). - 0002-0729 .- 1468-2834. ; 46:1, s. 64-71
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Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: the aim of this study was to identify whether factors beyond anatomical abnormalities are associated with low back pain (LBP) and LBP with sciatica (SCI) in older men. MATERIAL AND METHODS: Mister Osteoporosis Sweden includes 3,014 men aged 69-81 years. They answered questionnaires on lifestyle and whether they had experienced LBP and SCI during the preceding 12 months. About 3,007 men answered the back pain (BP) questions, 258 reported BP without specified region. We identified 1,388 with no BP, 1,361 with any LBP (regardless of SCI), 1,074 of those with LBP also indicated if they had experienced LBP (n = 615), LBP+SCI (n = 459). RESULTS: about 49% of those with LBP and 54% of those with LBP+SCI rated their health as poor/very poor (P < 0.001). Men with any LBP to a greater extent than those without BP had poor self-estimated health, depressive symptoms, dizziness, fall tendency, serious comorbidity (diabetes, stroke, coronary heart disease, pulmonary disease and/or cancer) (all P < 0.001), foreign background, were smokers (all P < 0.01), had low physical activity and used walking aids (all P < 0.05). Men with LBP+SCI to a greater extent than those with LBP had lower education, lower self-estimated health, comorbidity, dizziness and used walking aids (all P < 0.001). CONCLUSIONS: in older men with LBP and SCI, anatomical abnormalities such as vertebral fractures, metastases, central or lateral spinal stenosis or degenerative conditions may only in part explain prevalent symptoms and disability. Social and lifestyle factors must also be evaluated since they are associated not only with unspecific LBP but also with LBP with SCI.
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| 836. |
- Kherad, Mehrsa, et al.
(författare)
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The number and characteristics of prevalent vertebral fractures in elderly men are associated with low bone mass and osteoporosis.
- 2015
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Ingår i: The bone & joint journal. - 2049-4408. ; 97-B:8, s. 1106-10
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Tidskriftsartikel (refereegranskat)abstract
- We sought to determine whether specific characteristics of vertebral fractures in elderly men are associated with low bone mineral density (BMD) and osteoporosis. Mister Osteoporosis Sweden is a population based cohort study involving 3014 men aged 69 to 81 years. Of these, 1427 had readable lateral radiographs of the thoracic and lumbar spine. Total body (TB) BMD (g/cm²) and total right hip (TH) BMD were measured by dual energy x-ray absorptiometry. The proportion of men with osteoporosis was calculated from TH BMD. There were 215 men (15.1%) with a vertebral fracture. Those with a fracture had lower TB BMD than those without (p < 0.001). Among men with a fracture, TB BMD was lower in those with more than three fractures (p = 0.02), those with biconcave fractures (p = 0.02) and those with vertebral body compression of > 42% (worst quartile) (p = 0.03). The mean odds ratio (OR) for having osteoporosis when having any type of vertebral fracture was 6.1 (95% confidence interval (CI) 3.9 to 9.5) compared with those without a fracture. A combination of more than three fractures and compression in the worst quartile had a mean OR of 114.2 (95% CI 6.7 to 1938.3) of having osteoporosis compared with those without a fracture. We recommend BMD studies to be undertaken in these subcohorts of elderly men with a vertebral fracture.
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| 837. |
- Kihlander, Ingrid, 1976-, et al.
(författare)
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Certification of Innovation Management Professionals: Reasons for and Results from Acquiring Certification
- 2022
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Ingår i: Journal of Innovation Management. - : University of Porto. - 2183-0606. ; 10:1, s. 58-75
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Tidskriftsartikel (refereegranskat)abstract
- This paper addresses how personal certification in innovation management can contribute to the ongoing professionalisation within the innovation management discipline. The empirical study focused a project in Sweden initiated to develop qualification, specifically personal certification, of innovation management professionals. The project resulted in a certification process and a first batch of certified innovation management professionals. The study aimed to capture the individuals’ reasons for, as well as results and effects from, choosing to acquire a voluntary personal certification within innovation management. A wide range of reasons for taking the certifications was reported such as willingness to learn more; willingness to formalise innovation management competence; a wish to clarify roles, but also to promote the discipline itself. Certification was apprehended as a trustworthy format to achieve this. Identified effects were establishment of a common language, increased visibility of individuals, and innovation management professionals to feel more confident in their jobs.
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| 838. |
- Kihlander, Ingrid, 1976-, et al.
(författare)
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Chapter 1. Introduction
- 2022
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Ingår i: Changing the Dynamics and Impact of Innovation Management. - : World Scientific. - 9781800612099 ; , s. 3-7
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 839. |
- Kihlander, Ingrid, 1976-, et al.
(författare)
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Developing Innovation Leadership – The Relevance of Qualification and Certification of Innovation Management Professionals : Chapter 5
- 2023
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Ingår i: <em>Innovation Leadership in Practice</em>. - Leeds : Emerald Group Publishing Limited. - 9781837533978 - 9781837533961 ; , s. 79-
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- This chapter presents results from initial studies on personal certifications of innovation management professionals, drawing from a Swedish context. The results capture motivations for, as well as effects from, the certification process. They are discussed from the perspective of how this is relevant for developing and enhancing innovation leadership competencies. Increased knowledge, enhanced professional communication, and strengthened self-confidence related to innovation management were identified as outcomes for individuals pursuing the certifications. Further, this laid the ground for increased visibility, expanded network, and thus more opportunities to influence innovation work. An overarching theme appearing in the study is how a certification can contribute to strengthening the legitimacy of working with innovation management, and thus serve as an enabler for innovation management practice and subsequently innovation leadership. Effects from the certification that may be beneficial for successful innovation leadership include the opportunity for practitioners to articulate their own experiences and competencies, in addition to improving the impact of their efforts utilising innovation terminology. For organisations, knowledge of personal certification can be used both for recruitment and for development of existing personnel and their innovation leadership. Through a longer perspective, it can also contribute to decreasing the dependence on a few specific individuals and instead strengthen the long-term organisational innovation capabilities.
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| 840. |
- Kihlander, Ingrid, et al.
(författare)
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Developing innovation leadership-the relevance of qualification and certification of innovation management professionals
- 2023
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Ingår i: Innovation Leadership in Practice. - : Emerald. ; , s. 79-100
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- This chapter presents results from initial studies on personal certifications of innovation management professionals, drawing from a Swedish context. The results capture motivations for, as well as effects from, the certification process. They are discussed from the perspective of how this is relevant for developing and enhancing innovation leadership competencies. Increased knowledge, enhanced professional communication, and strengthened selfconfidence related to innovation management were identified as outcomes for individuals pursuing the certifications. Further, this laid the ground for increased visibility, expanded network, and thus more opportunities to influence innovation work. An overarching theme appearing in the study is how a certification can contribute to strengthening the legitimacy of working with innovation management, and thus serve as an enabler for innovation management practice and subsequently innovation leadership. Effects from the certification that may be beneficial for successful innovation leadership include the opportunity for practitioners to articulate their own experiences and competencies, in addition to improving the impact of their efforts utilising innovation terminology. For organisations, knowledge of personal certification can be used both for recruitment and for development of existing personnel and their innovation leadership. Through a longer perspective, it can also contribute to decreasing the dependence on a few specific individuals and instead strengthen the long-term organisational innovation capabilities.
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