Comparison of simulation results and field data on currents and density in Tokyo Bay

1996 ◽  
Vol 1 (2) ◽  
pp. 94-104 ◽  
Author(s):  
Shigeru Tabeta ◽  
Masataka Fujino
Author(s):  
Yasuyuki NAKAGAWA ◽  
Ryuich ARIJI ◽  
Kazuo NADAOKA ◽  
Hiroshi YAGI ◽  
Ken-ichiro SHIMOSAKO ◽  
...  

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Qingsong Hu ◽  
Lixin Wu ◽  
Fei Geng ◽  
Can Cao

WSN (wireless sensor network) is a perfect tool of temperature monitoring in coal goaf. Based on the three-zone theory of goaf, the GtmWSN model is proposed, and its dynamic features are analyzed. Accordingly, a data transmission scheme, named DTDGD, is worked out. Firstly, sink nodes conduct dynamic grid division on the GtmWSN according to virtual semicircle. Secondly, each node will confirm to which grid it belongs based on grid number. Finally, data will be delivered to sink nodes with greedy forward and hole avoidance. Simulation results and field data showed that the GtmWSN and DTDGD satisfied the lifetime need of goaf temperature monitoring.


2013 ◽  
Vol 423-426 ◽  
pp. 1394-1397
Author(s):  
Ming Chang Li ◽  
Guang Yu Zhang ◽  
Qi Si ◽  
Shu Xiu Liang ◽  
Zhao Chen Sun

Based on the hydrodynamic model and wind field data, a multi-module coupled oil spill model is constructed for simulating the trajectory of oil movement. A case study is researched in Bohai Bay. The model works well and the numerical simulation results show the model is suitable for oil spill trajectory simulation. Two cases are considered with and without wind to show its important influence for the oil spill.


Author(s):  
Alexander Skabardonis ◽  
Richard Dowling

Improved speed-estimation techniques for planning applications were developed and tested. Comparisons with field data and simulation results indicate that the recommended techniques provide better accuracy and consistency with the procedures contained in the 1994 update of the Highway Capacity Manual. These speed-estimation techniques will improve the accuracy of long-range transportation planning models for predicting travel time, delay, and air-pollutant emissions.


2020 ◽  
Author(s):  
Tony W. Carr ◽  
Juraj Balkovič ◽  
Paul E. Dodds ◽  
Christian Folberth ◽  
Emil Fulajtar ◽  
...  

Abstract. Water erosion in agricultural fields can reduce soil fertility and agricultural productivity. Despite the impact of water erosion on crops, it is typically neglected in global crop yield projections. Furthermore, previous efforts to quantify global water erosion have paid little attention to the effects of field management on the magnitude of water erosion. In this study, we analyse the robustness of simulated water erosion estimates in wheat and maize fields between the years 1980 to 2010 based on daily model outputs from a global gridded version of the Environmental Policy Integrated Climate (EPIC) crop model. Using the MUSS water erosion equation and country-specific and environmental indicators determining different intensities in tillage, residue handling and cover crops, we simulate global annual median and average water erosion rates of 6 t ha−1 and 19 t ha−1 and an annual soil removal of 7 Gt in global wheat and maize fields. A comparison of our simulation results with field data demonstrates an overlap of simulated and measured water erosion values for the majority of global cropland. Slope inclination and daily precipitation are key factors in determining the agreement between simulated and measured erosion values and are the most critical input parameters controlling all water erosion equations included in EPIC. The many differences between field management methods worldwide and the varying water erosion estimates from different equations add uncertainty to the simulation results. To reduce the uncertainties addressed here and to improve global water erosion estimates generally, more data on global field management and more field data from study sites representing the diversity of environmental conditions where crops are grown are necessary.


2020 ◽  
Vol 11 (11) ◽  
pp. 28-37
Author(s):  
Aleksey A. SUVOROV ◽  
◽  
Alexander S. GUSEV ◽  
Mikhail V. ANDREEV ◽  
Alisher B. ASKAROV ◽  
...  

The transient stability is the main condition for reliability and survivability operation of electric power system. The transient stability analysis is an extremely complex problem. It uses the results of numerical integration of differential equations that form a mathematical model of the power system. However, the mathematical model of a large-scale power system contains a rigid nonlinear system of extremely high-order differential equations. Such system cannot be solved analytically. The simplifications and limitations are used for improving the conditionality of the power system mathematical model in time-domain simulation. It decreases the reliability and accuracy of the simulation results. In this regard, it becomes necessary to validate them. The most reliable way of validation is to compare simulation results with field data. However, it is not always possible to receive the necessary amount of field data due to many power system states and a large amount of disturbances leading to instability. The paper proposes an alternative approach for validation: using an adequate model standard instead of field data. The prototype of Hybrid Real Time Power System Simulator having the necessary properties and capabilities has been used as the reference model. The appropriate sequence of actions has been developed for validation. The adequacy of proposed approach is illustrated by the fragments of the experimental studies


2021 ◽  
pp. 1-16
Author(s):  
Alina Boronina ◽  
Sergey Popov ◽  
Galina Pryakhina ◽  
Antonina Chetverova ◽  
Ekaterina Ryzhova ◽  
...  

Abstract In the afternoon of 30 January 2017, a catastrophic outburst flood occurred in the Larsemann Hills (Princess Elizabeth Land, East Antarctica). The rapid drainage of both a thin supraglacial layer of water (near Boulder Lake) and Lake Ledyanoe into the englacial Lake Dålk provoked its overfill and outburst. As a result, a depression of 183 m × 220 m was formed in the place where Lake Dålk was located. This study summarises and clarifies the current state of knowledge on the flood that occurred in 2017. We present a phenomenological model of depression formation. We specify the reasons for the outburst of the system of lakes Boulder, Ledyanoe and Dålk. In addition, we carry out mathematical modelling of the outburst of each of the three lakes and estimate the flood severity. Outburst hydrographs, channel diameters, volume and duration of floods were calculated. Particular simulation results were validated with field data. In conclusion, we give an overview of the new outburst cycle of the lake system, which began in 2020 with the drainage of the lakes Boulder and Ledyanoe, and the new formation of Lake Dålk. Further research is required to improve our understanding of the lake system responses to changing external factors.


2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Tao Deng ◽  
Jing Gong ◽  
Haihao Wu ◽  
Yu Zhang ◽  
Siqi Zhang ◽  
...  

Pigging in pipelines basically performs operations for five reasons including cleaning the pipe interior, batching or separating dissimilar products, displacement, measurement, and internal inspection. A model has been proposed for the dynamic simulation of the pigging process after water pressure testing in a long slope pipeline. In this study, an attempt has been made to analyze two serious accidents during pigging operation in 2010 by the model which is developed by the method of characteristic (MOC) by Wylie et al. (1993) and the two-phase homogeneous equilibrium vaporous cavitation model deveoped by Shu (2003) for vaporous cavitation. Moreover, simulation results of the third operation show good agreement with field data from the previous field trial. After investigation, it was showed that the impulse pressures produced during collapse of a vapor cavity result in severe damage of tubes.


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