scholarly journals State-of-the-art of port simulation models for risk and capacity assessment based on the vessel navigational behaviour through the nautical infrastructure

Author(s):  
Xavier Bellsolà Olba ◽  
Winnie Daamen ◽  
Tiedo Vellinga ◽  
Serge P. Hoogendoorn
Author(s):  
Johannes Nguyen ◽  
Thomas Farrenkopf ◽  
Michael Guckert ◽  
Simon T. Powers ◽  
Neil Urquhart

In state of the art research a growing interest in the application of agent models for the simulation of road traffic can be observed. Software agents are particularly suitable for the representation of travellers and their goal-oriented behaviour. Although numerous applications based on these types of models are already available, the options for modelling and calibration of the agents as goal-oriented individuals are either simplified to aggregated parameters or associated with overly complex and opaque implementation details. This makes it difficult to reuse available simulation models. In this paper, we demonstrate how the combination of persona models together with semantic methods can be applied to achieve a well-structured agent model that allows for improved reusability.


Author(s):  
Hideo Nakamura ◽  
Tadashi Watanabe ◽  
Takeshi Takeda ◽  
Hideaki Asaka ◽  
Masaya Kondo ◽  
...  

The Japan Atomic Energy Agency (JAEA) started OECD/NEA ROSA Project in 2005 to resolve issues in the thermal-hydraulic analyses relevant to LWR safety through the experiments of ROSA/LSTF in JAEA. More than 17 organizations from 14 NEA member countries have joined the Project. The ROSA Project intends to focus on the validation of simulation models and methods for complex phenomena that may occur during DBEs and beyond-DBE transients. Twelve experiments are to be conducted in the six types. By utilizing the obtained data, the predictability of codes is validated. Nine experiments have been performed so far in the ROSA Project to date. The results of two out of these experiments; PV top and bottom small-break (SB) LOCA simulations are studied here, through comparisons with the results from pre-test and post-test analyses by using the RELAP5/MOD3.2 code as a typical and well-utilized/improved best estimate (BE) code. The experimental conditions were defined based on the pre-test (blind) analysis. The comparison with the experiment results may clearly indicate a state of the art of the code to deal with relevant reactor accidents. The code predictive capability was verified further through the post-test analysis. The obtained issues in the utilization of the RELAP5 code are summarized as well as the outline of the ROSA Project.


SIMULATION ◽  
1967 ◽  
Vol 8 (2) ◽  
pp. 111-115
Author(s):  
J.O. Engle ◽  
C.J. Nisson

This paper was written for the analog user to relate some of our experience in the area of signal processing (in this case signal processing by a radar receiver) to fit the theme of the Eastern Simulation Council meeting at which it was presented. "In the paper we attempted to give a complete but simple picture; by describing the signals and system, de veloping the simulation models, instrumenting the models with available computing equipment and finally by dis cussing simulation difficulties. (We wish that we had more modern equipment so that the instrumentation, particu larly of the dc models, could be more significant relative to state-of-the-art.)"


2013 ◽  
Vol 37 ◽  
pp. 193-209 ◽  
Author(s):  
Dorine C. Duives ◽  
Winnie Daamen ◽  
Serge P. Hoogendoorn

2003 ◽  
Vol 13 (03) ◽  
pp. 701-725 ◽  
Author(s):  
ANTONIO ABRAMO

The progress of silicon technologies we have witnessed in the last twenty years has traced the path to the unprecedented revolution of information technologies, which has changed almost everybody's lifestyles. Apparently, this has happened with a little big help from TCAD tools. Big, because few major advancements have been achieved through the clever exploitation of non-conventional simulation tools, and because everyday device optimization deeply relies on TCAD tools. Little, because the qualitative feeling is that the technology would have progressed anyway, through the work of many highly-skilled technology experts, even without simulation guidelines. The purpose of this paper is to review the state-of-the-art of the field of the transport modeling of electron devices, trying to grasp the essence of the most relevant simulation models proposed so far, whence to contribute to spur the activity on the fundamental modeling of carrier transport.


2013 ◽  
Vol 26 (23) ◽  
pp. 9334-9347 ◽  
Author(s):  
Emma B. Suckling ◽  
Leonard A. Smith

While state-of-the-art models of Earth's climate system have improved tremendously over the last 20 years, nontrivial structural flaws still hinder their ability to forecast the decadal dynamics of the Earth system realistically. Contrasting the skill of these models not only with each other but also with empirical models can reveal the space and time scales on which simulation models exploit their physical basis effectively and quantify their ability to add information to operational forecasts. The skill of decadal probabilistic hindcasts for annual global-mean and regional-mean temperatures from the EU Ensemble-Based Predictions of Climate Changes and Their Impacts (ENSEMBLES) project is contrasted with several empirical models. Both the ENSEMBLES models and a “dynamic climatology” empirical model show probabilistic skill above that of a static climatology for global-mean temperature. The dynamic climatology model, however, often outperforms the ENSEMBLES models. The fact that empirical models display skill similar to that of today's state-of-the-art simulation models suggests that empirical forecasts can improve decadal forecasts for climate services, just as in weather, medium-range, and seasonal forecasting. It is suggested that the direct comparison of simulation models with empirical models becomes a regular component of large model forecast evaluations. Doing so would clarify the extent to which state-of-the-art simulation models provide information beyond that available from simpler empirical models and clarify current limitations in using simulation forecasting for decision support. Ultimately, the skill of simulation models based on physical principles is expected to surpass that of empirical models in a changing climate; their direct comparison provides information on progress toward that goal, which is not available in model–model intercomparisons.


Author(s):  
А.А. Губайдуллин ◽  
О.Ю. Болдырева ◽  
Д.Н. Дудко

Проведен анализ современного состояния экспериментальных и теоретических исследований упругих свойств гидратосодержащих пористых сред. Сделан вывод о том, что во всех экспериментах установлена связь скоростей упругих волн с содержанием гидрата в поровом пространстве, а именно, наблюдается рост скоростей с увеличением гидратонасыщенности. В области теоретических исследований созданы математические модели упругих модулей гидратосодержащих пористых сред, позволяющие качественно и количественно описать результаты лабораторных опытов. The state-of-the-art experimental and theoretical studies of the elastic properties of porous media containing gas hydrate was analyzed. It is concluded that all the experiments identified a relationship between the elastic wave velocities and the hydrate content in the porous space: the velocities increase with higher hydrate saturation. The theoretical research produced simulation models for estimating the modulus of elasticity of hydrate-containing porous media to qualitatively and quantitatively describe the results of laboratory experiments.


2021 ◽  
Vol 17 (8) ◽  
pp. e1009351
Author(s):  
Shenghao Yang ◽  
Priyabrata Senapati ◽  
Di Wang ◽  
Chris T. Bauch ◽  
Kimon Fountoulakis

Decision-making about pandemic mitigation often relies upon simulation modelling. Models of disease transmission through networks of contacts–between individuals or between population centres–are increasingly used for these purposes. Real-world contact networks are rich in structural features that influence infection transmission, such as tightly-knit local communities that are weakly connected to one another. In this paper, we propose a new flow-based edge-betweenness centrality method for detecting bottleneck edges that connect nodes in contact networks. In particular, we utilize convex optimization formulations based on the idea of diffusion with p-norm network flow. Using simulation models of COVID-19 transmission through real network data at both individual and county levels, we demonstrate that targeting bottleneck edges identified by the proposed method reduces the number of infected cases by up to 10% more than state-of-the-art edge-betweenness methods. Furthermore, the proposed method is orders of magnitude faster than existing methods.


2007 ◽  
Vol 158 (6) ◽  
pp. 128-141 ◽  
Author(s):  
Luuk Dorren ◽  
Frédéric Berger ◽  
Martin Jonsson ◽  
Michael Krautblatter ◽  
Michael Mölk ◽  
...  

To effectively prevent rockfall related disasters below forested slopes, silvicultural, eco-engineering, civil engineering or mixed techniques can be used. To do this in a cost-efficient manner it is necessary to know the following:1) where rockfall events occur and which magnitudes are likely, 2) to what extent the forest reduces the run-out distances, the jump heights and the energies of rocks falling downslope, and 3) how the protective function of forests could be improved. This paper gives an overview of the current scientific knowledge and methods that are applied by practitioners who deal with rockfall and forests protecting against it. Efficient ways to derive information on the probable magnitude and frequency of future rockfall events from the source and deposit area are described. Subsequently, the scientific knowledge on the energy absorption capacity of single trees and the currently available knowledge on the protective function of forest stands against rockfall are presented. Then easy-to-use tools and simulation models for rockfall hazard assessment on forested slopes are described. Finally, this paper identifies the most important challenges to be tackled in the field of integrated rockfall-forest research.


2014 ◽  
Vol 611-612 ◽  
pp. 436-443 ◽  
Author(s):  
Christian Mueller ◽  
Xun Gu ◽  
Lars Baeumer ◽  
Peter Groche

Roll forming is an important economic forming process for manufacturing of profiles. For an optimal design of the process, it is important to determine the loads occurring during the forming process. Furthermore, the information of the load behavior enables an evaluation of the formability of the planned profiles with the chosen roll forming machine. An experimental determination of loads in roll forming processes requires a complex measurement setup in combination with a high amount of measurement devices. Hence, the analysis of roll loads by means of finite element simulation is of special interest. The use of roll forming simulations for the determination of geometrical outputs is state of the art. However, due to simplifications, a realistic and reliable output of roll loads in roll forming is impossible. Therefore, the compliance behavior under load and the frictional behavior have to be incorporated in the simulation model. The friction behavior in roll forming processes is presented to be very insignificant in literature. The value of the friction coefficients vary in a broad range. Due to lack of knowledge in the compliance behavior of the used stands, simulation models with rigid rolls are still state of the art. This paper will show the reproduction of realistic roll loads, e.g. torques and forces, in a roll forming simulation. Therefore, the friction coefficients of each roll-sheet metal contact will be gained experimentally and implemented in the numerical model. Furthermore, a characteristic compliance of the roll forming stands will be analyzed and also considered in the simulation. Finally, the influence of changing parameters, e.g. raise of the friction coefficients, on the roll loads will be investigated. To verify the simulation the numerical results will be compared to data gained by experiments.


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