| 1. |
|
|
| 2. |
- Wersäll, Carl, et al.
(författare)
-
Roller compaction of rock-fill with automatic frequency control
- 2020
-
Ingår i: Proceedings of the Institution of Civil Engeneers. - : ICE Publishing. - 1353-2618 .- 1751-8563. ; 173:4, s. 339-347
-
Tidskriftsartikel (refereegranskat)abstract
- A new intelligent compaction method for vibratory soil compaction rollers that automatically and continuously adjusts the vibration frequency to obtain resonance in the coupled roller-soil system was evaluated in full-scale field tests on a 1 m high rock-fill embankment. This method has been called automatic frequency control (AFC). Compacting at the resonant frequency results in maximised deformations in the soil by optimising the dynamic behaviour of the system and improving the interaction between the drum and the soil. The embankment was also compacted conventionally at a fixed standard frequency in order to quantify the difference between the two methods. Applying AFC resulted in a higher degree of compaction of the embankment layer. The effect was most significant at the top of the embankment, where considerable compression was obtained - in contrast to the very loose material resulting from conventional compaction - thus eliminating the need for subsequent static passes. Spot tests showed a considerably stiffer embankment surface after a high number of passes using AFC. Other observed benefits of AFC include a more homogeneously compacted embankment, which benefits long-term behaviour, up to 15% reduced fuel consumption, reduced environmental impact and less machine wear.
|
|
| 3. |
- Di Benedetto, M. D., et al.
(författare)
-
Networked control
- 2009
-
Ingår i: Handbook of Hybrid Systems Control. - : Cambridge University Press. - 9780521765053
-
Bokkapitel (refereegranskat)
|
|
| 4. |
|
|
| 5. |
- Ananthanarayanan, G., et al.
(författare)
-
PACMan : Coordinated memory caching for parallel jobs
- 2012
-
Ingår i: Proceedings of NSDI 2012. - : USENIX Association. ; , s. 267-280
-
Konferensbidrag (refereegranskat)abstract
- Data-intensive analytics on large clusters is important for modern Internet services. As machines in these clusters have large memories, in-memory caching of inputs is an effective way to speed up these analytics jobs. The key challenge, however, is that these jobs run multiple tasks in parallel and a job is sped up only when inputs of all such parallel tasks are cached. Indeed, a single task whose input is not cached can slow down the entire job. To meet this "all-or-nothing" property, we have built PACMan, a caching service that coordinates access to the distributed caches. This coordination is essential to improve job completion times and cluster efficiency. To this end, we have implemented two cache replacement policies on top of PACMan's coordinated infrastructure fb-LIFE that minimizes average completion time by evicting large incomplete inputs, and LFU-F that maximizes cluster efficiency by evicting less frequently accessed inputs. Evaluations on production workloads from Facebook and Microsoft Bing show that PACMan reduces average completion time of jobs by 56% and 51% (small interactive jobs improve by 77%), and improves efficiency of the cluster by 47% and 54%, respectively.
|
|
| 6. |
- Krebs, Georgina, et al.
(författare)
-
The association between body dysmorphic symptoms and suicidality among adolescents and young adults : a genetically-informative study
- 2020
-
Ingår i: Behavior Genetics. - : Springer. - 0001-8244 .- 1573-3297. ; 50:6, s. 462-462
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Previous research indicates that body dysmorphic disorder (BDD) is associated with risk of suicidality. However, studies have relied on small and/or specialist samples and largely focused on adults, despite these difficulties commonly emerging in youth. Furthermore, the aetiology of the relationship remains unknown.Two independent twin samples were identified through the Child and Adolescent Twin Study in Sweden, at ages 18 (N = 6027) and 24 (N = 3454). Participants completed a self-report measure of BDD symptom severity. Young people and parents completed items assessing suicidal ideation and suicide attempts. Logistic regression models tested the association between continuous scores of BDD symptoms and suicidality outcomes. Bivariate genetic models examined the aetiology of the association between BDD symptoms and a suicidality composite at both ages.BDD symptoms were positively associated with suicidal ideation and suicide attempts at age 18 and 24. These associations generally remained significant after adjusting for depressive and anxiety symptoms. Genetic factors accounted for most of the covariance between BDD symptoms and suicidality (74.1% and 79.4% at ages 18 and 24, respectively), but with significant non-shared environmental influences (25.9% and 20.6% at ages 18 and 24, respectively).BDD symptoms are associated with substantial risk of suicidal ideation and behaviours in late adolescence and early adulthood. This relationship is largely explained by common genetic liability, but non-shared environmental effects are also significant and could provide opportunities for prevention among those at high-risk.
|
|
| 7. |
- Ribeiro, Luis, et al.
(författare)
-
Industrial Agents for the Fast Deployment of Evolvable Assembly Systems
- 2015. - 1st ed.
-
Ingår i: Industrial Agents. - Amsterdam, Netherlands : Elsevier. - 9780128003411 ; , s. 301-321, s. 301-322
-
Bokkapitel (refereegranskat)abstract
- The current manufacturing scenario is characterized by high market unpredictability. Agility is therefore a central challenge for modern companies that need to understand and be proactive towards their product offer in respect to “what is offered, when it is offered, where, how and by whom” (Brown & Bessant 2003).The “what” and the “when” are particularly relevant to the research in emerging paradigms as they account for variety, customization and volume; and timing, speed and seasonality (Brown & Bessant 2003).In this scenario, several design approaches and models have been proposed in the last decade to enable re-configurability and subsequently enhance the companies’ ability to adjust their offer in nature and time.From a paradigmatic point of view research has concentrated on the organizational structure of the shop-floor and the associated controls aspects. Concepts like Reconfigurable Manufacturing Systems (RMS) (Koren & Shpitalni 2010) and Fractal Factories (FF) (Montreuil 1999) support the physical construction of production systems by regulating their layout and making a few assumptions on their logical organization. On the other hand, concepts like Bionic Manufacturing Systems (BMS)(Ueda 1992), Holonic Manufacturing Systems (HMS)(Van Brussel et al. 1998), Evolvable Assembly Systems (Ribeiro et al. 2010) essentially provide the theoretical guidelines for the logical/computational organization of the system (see (Tharumarajah 1996) for a comparison between BMS, HMS and FF and (Setchi & Lagos 2004) for the rationale supporting the shift from Dedicated Lines to Flexible Manufacturing System and finally RMS).While these paradigms provide the conceptual framework and the main design guidelines their actual interpretation and implementation has led to a wider set of architectures (Monostori, Váncza & Kumara 2006; Leitão 2009; Parunak 2000; Pěchouček & Mařík 2008).These architectures align the high-level principles with the technological offer and limitations while seeking to address the re-configurability requirements of (Mehrabi, Ulsoy & Koren 2000; Rösiö & Säfsten 2013):module mobility – modules are easy and quick to move and install;“diagnosability” – it is quick to identify the sources of quality and reliability problems;“integrability” – modules are easy to integrate into the rest of the system.“convertibility” – it is easy and quick to switch between existing products and it is easy to adapt the system to future products;scalability – it is easy to enlarge and downsize the production system;“automatibility” – a dynamic level of automation is enabled;modularity – all system elements are designed to be modular;customization – the capability and flexibility of the production system is designed according to the products to be produced in the system.Instant deployment, as addressed in the present chapter directly addresses mobility, “integrability”, “convertibility”, scalability and customization. Mechatronic modularity is a prerequisite and is enforced by the proposed architecture and the considered modular design. “Diagnosability” was not specifically tackled.In this context, the chapter analyses the agent-based architecture related with the Instantly Deployable Evolvable Assembly System (IDEAS) project that is inspired by the Evolvable Assembly System (EAS) paradigm (Ribeiro et al. 2010) as a mechanism to enable fast deployment of mechatronic modules. EAS advocates the use of process-oriented modules and envisions the production system as a collection of processes and the associated interacting agents.The architecture and the related test cases are used to draw the main lessons learned in respect to technological and conceptual implications.In this context, the remainder of this text is organized as follows: section 1.1 discusses the main deployment challenges, section 1.2 details the reference architecture and associated concepts, section 1.3 presents the principal implementation decisions, section 1.4 features the main lessons learned, sections 1.5 discusses the benefits of the proposed approach and finally section 1.6 reflects on the main conclusions.
|
|
| 8. |
- Zambelli, Martina, et al.
(författare)
-
Posture regulation for unicycle-like robots with prescribed performance guarantees
- 2015
-
Ingår i: IET Control Theory & Applications. - : Institution of Engineering and Technology (IET). - 1751-8644 .- 1751-8652. ; 9:2, s. 192-202
-
Tidskriftsartikel (refereegranskat)abstract
- This study aims to address the regulation problem for the unicycle model while guaranteeing prescribed performance. Different controllers based either on polar coordinates or time-varying laws are proposed. The main contribution is the combination of the standard control laws that allow to achieve posture regulation for the unicycle, with the prescribed performance control technique that imposes time-varying constraints to the system coordinates. To apply prescribed performance to the unicycle system which is subject to a non-holonomic constraint, the authors design a specific transformation function that is instrumental in the proof of asymptotic convergence with prescribed guaranties.
|
|
| 9. |
- Aleksandrova, Krasimira, et al.
(författare)
-
Circulating C-reactive protein concentrations and risks of colon and rectal cancer : a nested case-control study within the European Prospective Investigation into Cancer and Nutrition
- 2010
-
Ingår i: American Journal of Epidemiology. - : Oxford University Press (OUP). - 0002-9262 .- 1476-6256. ; 172:4, s. 407-418
-
Tidskriftsartikel (refereegranskat)abstract
- The authors investigated associations between serum C-reactive protein (CRP) concentrations and colon and rectal cancer risk in a nested case-control study within the European Prospective Investigation into Cancer and Nutrition (1992-2003) among 1,096 incident cases and 1,096 controls selected using risk-set sampling and matched on study center, age, sex, time of blood collection, fasting status, menopausal status, menstrual cycle phase, and hormone replacement therapy. In conditional logistic regression with adjustment for education, smoking, nutritional factors, body mass index, and waist circumference, CRP showed a significant nonlinear association with colon cancer risk but not rectal cancer risk. Multivariable-adjusted relative risks for CRP concentrations of > or = 3.0 mg/L versus <1.0 mg/L were 1.36 (95% confidence interval (CI): 1.00, 1.85; P-trend = 0.01) for colon cancer and 1.02 (95% CI: 0.67, 1.57; P-trend = 0.65) for rectal cancer. Colon cancer risk was significantly increased in men (relative risk = 1.74, 95% CI: 1.11, 2.73; P-trend = 0.01) but not in women (relative risk = 1.06, 95% CI: 0.67, 1.68; P-trend = 0.13). Additional adjustment for C-peptide, glycated hemoglobin, and high density lipoprotein cholesterol did not attenuate these results. These data provide evidence that elevated CRP concentrations are related to a higher risk of colon cancer but not rectal cancer, predominantly among men and independently of obesity, insulin resistance, and dyslipidemia.
|
|
| 10. |
|
|
