111 research outputs found
sj-pdf-3-jhs-10.1177_17531934221085401 - Supplemental material for Factors associated with self-reported pain and hand function following surgical A1 pulley release
No full textSupplemental material, sj-pdf-3-jhs-10.1177_17531934221085401 for Factors associated with self-reported pain and hand function following surgical A1 pulley release by Jaimy E. Koopman, Caroline A. Hundepool, Robbert M. Wouters, Liron S. Duraku, Jeroen M. Smit, Ruud W. Selles, the Hand-Wrist study group J. Michiel Zuidam in Journal of Hand Surgery (European Volume)</p
sj-pdf-1-jhs-10.1177_17531934241232341 - Supplemental material for Incision techniques for trigger thumb release: a comparison of outcomes of four types of skin incision
No full textSupplemental material, sj-pdf-1-jhs-10.1177_17531934241232341 for Incision techniques for trigger thumb release: a comparison of outcomes of four types of skin incision by Jaimy E. Koopman, Jeroen M. Smit, Robbert M. Wouters, Ruud W. Selles, J. Michiel Zuidam, Hand-Wrist Study Group Caroline A. Hundepool in Journal of Hand Surgery (European Volume)</p
sj-pdf-2-jhs-10.1177_17531934221085401 - Supplemental material for Factors associated with self-reported pain and hand function following surgical A1 pulley release
No full textSupplemental material, sj-pdf-2-jhs-10.1177_17531934221085401 for Factors associated with self-reported pain and hand function following surgical A1 pulley release by Jaimy E. Koopman, Caroline A. Hundepool, Robbert M. Wouters, Liron S. Duraku, Jeroen M. Smit, Ruud W. Selles, the Hand-Wrist study group J. Michiel Zuidam in Journal of Hand Surgery (European Volume)</p
sj-pdf-1-jhs-10.1177_17531934221085401 - Supplemental material for Factors associated with self-reported pain and hand function following surgical A1 pulley release
No full textSupplemental material, sj-pdf-1-jhs-10.1177_17531934221085401 for Factors associated with self-reported pain and hand function following surgical A1 pulley release by Jaimy E. Koopman, Caroline A. Hundepool, Robbert M. Wouters, Liron S. Duraku, Jeroen M. Smit, Ruud W. Selles, the Hand-Wrist study group J. Michiel Zuidam in Journal of Hand Surgery (European Volume)</p
Deep Reinforcement Learning for the Synthesis of Self-Triggered Sampling Strategies
No full textControl engineering researchers are increasingly embracing data-driven techniques like reinforcement learning for control and optimisation. An example of a case where reinforcement learning could be useful is the synthesis of near-optimal sampling strategies for self-triggered control. Self-triggered control is an aperiodic control method that aims to reduce the number of communications between the controller and sensors in a control loop, by predicting when some triggering condition is met and only transmitting a sample accordingly. Recent research has shown that greedily following the proposed sampling times can result in sub-optimal long-term average inter-sample times. Abstraction-based methods have been able to synthesise sampling strategies that result in better long-term average inter-sample times, by allowing for early sampling and considering the proposed sampling times as deadlines. However, these abstraction-based methods suffer greatly from the curse of dimensionality in the form of combinatorial explosion, which limits their practicality for more complex systems. This thesis proposes a novel deep reinforcement learning tool for finding near-optimal sampling strategies for self-triggered control of LTI systems. The proposed tool is evaluated and compared to a state-of-the-art abstraction-based method. The proposed tool is shown to match the performance of the abstraction-based method for smaller systems, while still achieving good results on more complex systems that prohibit the use of abstraction-based methods.Mechanical Engineering | Systems and Contro
Assessing the performance of the sonAIR aircraft noise model in predicting noise levels at Schiphol Airport
No full textAircraft noise is a significant problem for communities surrounding airports. Accurate prediction models are needed to estimate noise levels from aircraft operations. In this research, the accuracy of the sonAIR aircraft noise model is evaluated in predicting noise levels around Schiphol airport by comparison to measurement data from NOMOS and the current best-practice modelling approach Doc29. Results show a significant but consistent underestimation of noise levels by sonAIR, mainly due to a generalisation of emission models. The standard deviation of differences between model results and measurements is lower for sonAIR than for Doc29 by up to 1 dB. Differences between measurement and model results were found in the relation between N1 and noise levels, maximum noise levels and frequency spectra. These results demonstrate that sonAIR provides more reliable predictions of noise levels on the single flight event level than Doc29. Additionally, this study shows agreement with results from a previous validation study in Zürich, thereby confirming the applicability of sonAIR to another airport. This research contributes to better aircraft noise predictions, which will have implications ultimately leading to a better quality of life for communities affected by aircraft noise.Aerospace Engineerin
A co-creational approach in the Dutch infrastructure sector: Exploring the added value of implementing a co-creational approach in the pre-contractual phase
No full textRecently a new phenomenon introduced itself in the Dutch infrastructure sector called co-creation. It is described in literature as ‘the joint creation of value between a company and its consumers’. It marks a shift in thinking and became a popular concept to increase the participation of consumers around the year 2000. Since then it has spread to other industries. In the service-and product design it already proved to be a good method as benefits such as increased satisfaction among consumers, cost reduction for the firm and innovative ideas has been mentioned in literature. . In this research, seven elements are identified that are found as necessary conditions for the co-creation concept. With decomposing it into elements it was found that the concept became less abstract, making it more practical for project leaders to implement the concept in their projects. Co-creation in the infrastructure sector is about placing the stakeholder in a central position and together identify their needs and investigate how value can be created jointly
Defining the effectiveness of urban runoff measures: A model study
No full textUrban climate adaptation is generally attained --- in a hydrological perspective -- by implementing stormwater management techniques, such as grey, blue and green adaptation measures. Implementing such multi-functional adaptation measures touches on the interests of many stakeholders who need to work together to find resilient and suiting solutions in urban climate adaptation. To facilitate this cooperation, Deltares developed the Adaptation Support Tool. The AST defines eight different performance indicators to compare the effectiveness of urban runoff reduction measures, among which the runoff volume reduction factor. This factor is defined as the rate at which a specific adaptation measure increases the return time of the extreme runoff event. This factor is determined by the underlying model of the AST, the Urban Water Balance Model (UWBM).The UWBM has the benefit of using long times series instead of single precipitation events (design storms) as input to determine the effectiveness of measures; antecedent conditions for every extreme event are therefore known. Currently, the UWBM is only determining the runoff volume reduction factor. At the same time, the literature shows the importance of analysing the effectiveness of measures using both flow peak reduction and storage peak reduction. Exploration of the possibility to implement these two reduction factors into the UWBM forms the challenge of this study. This research aims to define a flow peak- and storage peak reduction factor based on modelling systems in the UWBM using long time series. Because the model describes these factors over the measure area, the second goal of this study is to investigate the possibility of converting this measure factor to a whole project area factor and combining this factor for a combination of measures. Main conclusions of this research are as follows: A flow peak reduction factor can be empirically determined based on the proposed method in this study. A storage peak reduction factor can not be empirically determined based on the proposed method in this study. It is recommended to do more research into the analysis of the storage peaks using time series, since it can give an extra insight into the effectiveness of measures. Converting the found flow peak reduction factor for the measure area to the project area with multiple interventions is substantiated with a proposed equation. However, it is recommended to do more research into the conversion equation to be used in the Adaptation Support Tool. By determining the flow peak reduction factor together with the runoff volume reduction factor, the effectiveness of urban runoff reduction measures in a project area can be quantified and used to compare alternative solutions for their effectiveness in flood risk reduction. The added flow peak reduction factor gives a more thorough insight into this effectiveness of measures. Water Resources Engineerin
The sheet pile behaviour for hole weakening
No full textThe evolution of ships requires larger depth or larger terrain loads in ports. Therefore, the existing quay walls require reinforcements. An effective way of reinforcing the structure are underwater anchors, requiring holes in existing sheet piles at the location of significant bending moment. Since this is a new area of expertise, the influence of the hole is still unknown. This report discusses a developed finite element model to study the influence of hole weakening of sheet pile and studies the influence of hole weakening on the sheet pile resistance and behaviour with the discussed model. The 3DSSI model includes soil modelled by the subgrade reaction model (spring model) the steel sheet pile is modelled with shell elements in the finite element software DIANA FEA. The model includes both physical nonlinear and geometrical nonlinear behaviour and captures the soil-structure interaction. Also oblique bending, which is an existing phenomena of older, existing double U-sheet piles, can be captured with interface elements in the 3DSSI model. Nowadays, sheet piles are also designed using the subgrade reaction model and the sheet pile is modelled as a beam with the appropriate stiffness. The 3DSSI model is able to illustrate the 3D behaviour of the sheet pile, without having to model the soil with solid elements as well. This is beneficial with respect to calculation time. With the 3DSSI model, the hole weakening of sheet piles can be studied. The influence of different parameters on the sheet pile resistance and behaviour is studied. The parameters studied, based on literature findings, are: hole diameter, hole location (level of the hole in depth), hole spacing (hole centre to centre distance in width), hole in-pan (compression zone) or out-pan (tension zone), sheet pile cross-section class 2 and 3 and oblique bending. The influence of hole weakening on sheet pile behaviour and resistance is studied by finding in the parameter study for each case the load-displacement curve and from this load-displacement curve, the stiffness is derived. The load-displacement curve and stiffness curve include both steel and soil behaviour. Resulting from the parameter study, the holes significantly reduce the sheet pile resistance and behaviour. The cases with holes in tension show less reduction in resistance and stiffness reduction. The hole diameter is also influencing the results, but the influence of hole location and hole spacing is relatively small. The failure modes are for holes in compression zone is plasticity around the hole and local buckling in the webs. For holes in tension zone, the failure mode is also plasticity around the hole, but also local buckling in the compression flange. For cases including oblique bending and holes in tension zone do not show local buckling in the compression flange, but in the compression web, due to the inclined neutral axis caused by oblique bending.Civil Engineerin
Riccardia innovans Pagan
No full text<i>Riccardia innovans</i> (Steph.) Pagán (Figs 2 -4) <p> <i>The Bryologist</i> 45: 80 (1942). <i>—</i> Basionym: <i>Aneura innovans</i> Steph., in Urban, <i>Symbolae Antillarum</i> 2: 470 (1901). — Type: Guadeloupe, Savane-à-Mulets, «Sur les arbrisseaux », 1901, <i>Duss</i></p> <p> <i>484,</i> ex hb. Urban (lecto-, designated here, G[G00066662!], <i>c</i>. gyn.; isolecto-, NY n.v., fide Pagán 1942).</p> <i>Description</i> <p> The outstanding characters of <i>R. innovans</i> are the very delicate, 2-pinnate plants with a very narrow (150-250 µm in diameter), biconvex, almost wingless axis and numerous long and narrow, linear to subulate branches. The branches are only little narrower than the axis, plano-convex, obliquely to widely spreading, usually tapering to narrow tips, and narrowly winged by 1-2 cell wide wings. The presence of small scales on the calyptra, made up of large cells, may be a further characteristic of the species. The plants are dioicous; gemmae have not been observed.</p> <i>Remarks</i> <p> <i>Riccardia innovans</i> approaches <i>R. regnellii</i> (Ångstr.) K.G.Hell, but the latter is a larger plant with a flat axis (not biconvex) and with broader, frequently tongue-shaped branches. In the type material, some <i>R. regnellii</i> plants are growing mixed in the dense mat of <i>R. innovans</i> and are immediately recognized by their much larger size. <i>Riccardia innovans</i> is thus far only</p> <p> known from the type. A field search by the second author in the type locality and elsewhere has not revealed further populations of the species. The taxonomic relationships of the species will be dealt with in a comprehensive study on the genus <i>Riccardia</i> in Guadeloupe (Lavocat Bernard & Reeb in prep.).</p>Published as part of <i>Gradstein, S. Robbert & Bernard, Elisabeth Lavocat, 2020, An evaluation of the endemic bryophyte flora of Guadeloupe, pp. 205-214 in Cryptogamie, Bryologie 20 (15)</i> on pages 206-207, DOI: 10.5252/cryptogamie-bryologie2020v41a15, <a href="http://zenodo.org/record/7822144">http://zenodo.org/record/7822144</a>
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