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| 2. |
- Al Khatib, Iyad, 1975-
(författare)
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Performance Analysis of Application-Specific Multicore Systems on Chip
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The last two decades have witnessed the birth of revolutionary technologies in data communications including wireless technologies, System on Chip (SoC), Multi Processor SoC (MPSoC), Network on Chip (NoC), and more. At the same time we have witnessed that performance does not always keep pace with expectations in many services like multimediaservices and biomedical applications. Moreover, the IT market has suffered from some crashes. Hence, this triggered us to think of making use of available technologies and developing new ones so that the performance level is suitable for given applications and services. In the medical field, from a statistical viewpoint, the biggest diseases in number of deaths are heart diseases, namely Cardiovascular Disease (CVD) and Stroke. The application with the largest market for CVD is the electrocardiogram (ECG/EKG) analysis. According to the World Health Organization (WHO) report in 2003, 29.2% of global deaths are due to CVD and Stroke, half of which could be prevented if there was proper monitoring. We found in the new advance in microelectronics, NoC, SoC, and MPSoC, a chance of a solution for such a big problem. We look at the communication technologies, wireless networks, and MPSoC and realize that many projects can be founded, and they may affect people's lives positively, as for example, curing people more rapidly, as well as homecare of such large scale diseases. These projects have a medical impact as well as economic and social impacts. The intention is to use performance analysis of interconnected microelectronic systems and combine it with MPSoC and NoC technologies in order to evolve to new systems on chip that may make a difference. Technically, we aim at rendering more computations in less time, on a chip with smaller volume, and with less expense. The performance demand and the vision of having a market success, i.e. contributing to lower healthcare costs, pose many challenges on the hardware/software co-design to meet these goals. This calls upon the development of new integrated circuits featuring increased energy efficiency while providing higher computation capabilities, i.e. better performance. The biomedical application of ECG analysis is an ideal target for an application-specific SoC implementation. However, new 12-lead ECG analyses algorithms are needed to meet the aforementioned goals. In this thesis, we present two novel algorithms for ECG analysis, namely the Autocorrelation-Function (ACF) based algorithm and the Fast Fourier Transform (FFT) based algorithm. In this respect, we explore the design space by analyzing different hardware and software architectures. As a result, we realize a design with twelve processors that can compute 3.5 million arithmetic computations and respect the real time hard deadline for our biomedical application (3.5-4seconds), and that can deploy the ACF-based and FFT-based algorithms. Then, we investigate the configuration space looking for the most effective solution, performance and energy-wise. Consequently, we present three interconnect architectures (Single Bus, Full Crossbar, and Partial Crossbar) and compare them with existing solutions. The sampling frequencies of 2.2 KHz and 4 KHz, with 12 DSPs, are found to be the critical points for our Shared-Bus design and Crossbar architecture, respectively. We also show how our performance analysis methods can be applied to such a field of SoC design and with a specific purpose application in order to converge to a solution that is acceptable from a performance viewpoint, meets the real-time demands, and can be implemented with the present technologies while at the same time paving the way for easier and faster development. In order to connect our MPSoC solution to communication networks to transmit the medical results to a healthcare center, we come up with new protocols that will allow the integration of multiple networks on chips in a communication network. Finally, we present a methodology for HW/SW Codesign for application-specific systems (with focus on biomedical applications) that require a large number of computations since this will foster the convergence to solutions that are acceptable from a performance point of view.
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| 3. |
- Aunola, Kaisa, et al.
(författare)
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Adolescents' achievement strategies, school adjustment, and externalizing and internalizing problem behaviors
- 2000
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Ingår i: Journal of Youth and Adolescence. - Berlin : Springer Berlin/Heidelberg. - 0047-2891 .- 1573-6601. ; 29:3, s. 289-306
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Tidskriftsartikel (refereegranskat)abstract
- Investigated the relationships between the achievement strategies adolescents deploy in a school context, and their self-esteem, school adjustment, and internalizing and externalizing problem behaviors. A total of 1,185 14-15 yr old adolescents filled in the Strategy and Attribution Questionnaire, Rosenberg's Self-Esteem Scale, and scales measuring school adjustment, depression and externalizing problem behavior. The adolescents' parents were also asked to evaluate their children's achievement strategies, school adjustment, and externalizing problem behavior. Results reveal that low self-esteem was associated with adolescents' use of maladaptive achievement strategies which, in turn, was associated with their maladjustment at school, and internalizing and externalizing problem behaviors. Moreover, the association between adolescents' maladaptive strategies and their externalizing problem behavior was partly mediated via their school adjustment. The results suggest that the achievement strategies adolescents deploy are reflected not only in their school adjustment but also in their overall problem behavior.
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| 4. |
- Aunola, Kaisa, et al.
(författare)
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Parenting styles and adolescents' achievement strategies
- 2000
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Ingår i: Journal of Adolescence. - Amsterdam : Elsevier. - 0140-1971 .- 1095-9254. ; 23:2, s. 205-222
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Tidskriftsartikel (refereegranskat)abstract
- Investigated the extent to which adolescents' achievement strategies are associated with the parenting styles they experience in their families. 354 adolescents (median age 14 yrs) completed a Strategy and Attribution Questionnaire and a family parenting style inventory. Analogous questionnaires were also completed by the adolescents' parents. Based on adolescents' report of the parenting styles, 4 types of families were identified: those with Authoritative, Authoritarian, Permissive, and Neglectful parenting styles. The results further showed that adolescents from authoritative families applied most adaptive achievement strategies characterized by low levels of failure expectations, task irrelevant behavior and passivity, and the use of self-enhancing attributions. Adolescents from neglectful families, in turn, applied maladaptive strategies characterized by high levels of task-irrelevant behavior, passivity and a lack of self-enhancing attributions. The results provide a basis for understanding some of the processes by which parenting styles may influence adolescents' academic achievement and performance.
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| 5. |
- Bergman, Lars R., et al.
(författare)
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I-states-as-objects-analysis (ISOA) : Extensions of an approach to studying short-term developmental processes by analyzing typical patterns
- 2012
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Ingår i: International Journal of Behavioral Development. - : SAGE Publications. - 0165-0254 .- 1464-0651. ; 36:3, s. 237-246
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Tidskriftsartikel (refereegranskat)abstract
- I-states-as-objects-analysis (ISOA) is a person-oriented methodology for studying short-term developmental stability and change in patterns of variable values. ISOA is based on longitudinal data with the same set of variables measured at all measurement occasions. A key concept is the i-state, defined as a person's pattern of variable values at a specific time point. All i-states are first subjected to a classification analysis that results in a time-invariant classification characterized by a number of typical i-states. Each person is then characterized at each time point by the typical i-state he/she belongs to. Then the person's sequences of typical i-states are analyzed with regard to structural and individual stability and change. Extensions of ISOA are presented where: (1) some methods for checking the assumption of a time-invariant classification are indicated; (2) information about the degree of dissimilarity between typical i-states is used as an aid in interpreting the findings; and (3) attention is given to closed paths-that is, typical i-state sequences that do not occur at all. To demonstrate the methods, an empirical example is given that concerns the development of children's achievement-intelligence patterns between ages 10 and 13.
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| 6. |
- Bergman, Lars R., et al.
(författare)
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Studying patterns of individual development by I-States as Objects Analysis (ISOA)
- 2010
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Ingår i: International Society for the Study of Behavioural Development Bulletin. ; 57:1, s. 7-10
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Tidskriftsartikel (refereegranskat)abstract
- I-States-as-Objects-Analysis (ISOA) is a methodology for studying short-term developmental stability and change in patterns of variable values. The theoretical rationale for this methodology is the person-oriented research paradigm. A key concept is the i-state, defined as a person's pattern of variable values at a specific time point. Hence, if there are k time points, each person is characterized by k i-states. All i-states are first subjected to a classification analysis that results in each person being characterized at each time point by a class membership in the time-invariant classification system. Then, the individuals' sequences of typical i-state belongingness are analyzed with regard to structural and individual stability and change.
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| 7. |
- Cavo, Luis, et al.
(författare)
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Implementation of an area efficient crypto processor for a NB-IoT SoC platform
- 2018
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Ingår i: 2018 IEEE Nordic Circuits and Systems Conference, NORCAS 2018 : NORCHIP and International Symposium of System-on-Chip, SoC 2018 - Proceedings - NORCHIP and International Symposium of System-on-Chip, SoC 2018 - Proceedings. - 9781538676561
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Konferensbidrag (refereegranskat)abstract
- This paper presents a cryptographic processor compliant with the security algorithms specified by the 3rd Generation Partnership Project (3GPP) specifications for Long Term Evolution (LTE). The proposed processor has been adapted to the needs of the low end portfolio technologies that compose the Internet of Things (IoT) market, which addresses low-Area, low-cost and low-data rate applications. The cryptographic processor has been described using the High-Level Synthesis (HLS) design flow and integrated with a CPU in a cycle accurate virtual platform. Various architectural optimizations are proposed in order to achieve a reduction of area ranging from 5% to 42% in comparison to similar work. In a 65-nm CMOS technology, the processor has a size of 53.6 kGE, and is capable of performing at 52.4 Mbps for the block cipher and 800 Mbps for the stream cipher algorithms at a 100 MHz clock.
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| 8. |
- Daniel, Ondrej, et al.
(författare)
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Blind sub-Nyquist GNSS signal detection
- 2016
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Ingår i: ICASSP, IEEE International Conference on Acoustics, Speech and Signal Processing - Proceedings. - 1520-6149. ; 2016-May, s. 6575-6579
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Konferensbidrag (refereegranskat)abstract
- A satellite navigation receiver traditionally searches for positioning signals using an acquisition procedure. In situations, in which the required information is only a binary decision whether at least one positioning signal is present or absent, the procedure represents an unnecessarily complex solution. This paper presents a different approach for the binary detection problem with significantly reduced computational complexity. The approach is based on a novel decision metric which is utilized to design two binary detectors. The first detector operates under the theoretical assumption of additive white Gaussian noise and is evaluated by means of Receiver Operating Characteristics. The second one considers also additional interferences and is suitable to operate in a real environment. Its performance is verified using a signal captured by a receiver front-end.
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| 9. |
- Daniel, Ondrej, et al.
(författare)
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Delay-Accuracy Tradeoff in Opportunistic Time-of-Arrival Localization
- 2018
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Ingår i: IEEE Signal Processing Letters. - 1070-9908 .- 1558-2361. ; 25:6, s. 763-767
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Tidskriftsartikel (refereegranskat)abstract
- While designing a positioning network, the localization performance is traditionally the main concern. However, collection of measurements together with channel access methods require a nonzero time, causing a delay experienced by network nodes. This fact is usually neglected in the positioning-related literature. In terms of the delay-accuracy tradeoff, broadcast schemes have an advantage over unicast, provided nodes can be properly synchronized. In this letter, we analyze the delay-accuracy tradeoff for localization schemes in which the position estimates are obtained based on broadcasted ranging signals. We find that for dense networks, the tradeoff is the same for cooperative and noncooperative networks, and cannot exceed a certain threshold value.
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| 10. |
- Daniel, Ondrej, et al.
(författare)
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Hybrid Cooperative Positioning in Harsh Environments
- 2015
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Ingår i: IEEE Globecom Workshops. - 9781467395267
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Konferensbidrag (refereegranskat)abstract
- Hybrid cooperative positioning involves the combination of satellite pseudoranges with measurements based on terrestrial radio signals, with the aim to improve both coverage and accuracy. This paper presents a theoretical analysis of hybrid cooperative positioning in low signal-to-noise ratio environments, explicitly accounting for scenarios where receivers can receive signals but cannot decode navigation messages. We propose an extended pseudorange model, suitable for evaluation of measurements made by the receiver in these scenarios, as well as extended cooperation across agents attempting to enable satellite navigation functionality of receivers operating below signal-to-noise ratio threshold required for proper message decoding. The advantages of such extended cooperation are illustrated on a realistic scenario by means of the Cramer-Rao lower bound.
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