Cartesian Meshing Spherical Earth (CMSE): A Code Package to Incorporate the Spherical Earth in SPECFEM3D Cartesian Simulations

2022 ◽  
Author(s):  
Guoliang Li ◽  
Kai Tao ◽  
Min Chen ◽  
Jiaqi Li ◽  
Ross Maguire ◽  
...  
Keyword(s):  
Regional Scale ◽  
Maximum Amplitude ◽  
Seismic Wave Propagation ◽  
Coordinate Frame ◽  
Polar Regions ◽  
Fully Integrated ◽  
Mercator Projection ◽  
Spherical Earth ◽  
Cartesian Coordinate ◽  
The One

Abstract The SPECFEM3D_Cartesian code package is widely used in simulating seismic wave propagation on local and regional scales due to its computational efficiency compared with the one-chunk version of the SPECFEM3D_Globe code. In SPECFEM3D_Cartesian, the built-in meshing tool maps a spherically curved cube to a rectangular cube using the Universal Transverse Mercator projection (UTM). Meanwhile, the geodetic east, north, and up directions are assigned as the local x–y–z directions. This causes coordinate orientation issues in simulating waveform propagation in regions larger than 6° × 6° or near the Earth’s polar regions. In this study, we introduce a new code package, named Cartesian Meshing Spherical Earth (CMSE), that can accurately mesh the 3D geometry of the Earth’s surface under the Cartesian coordinate frame, while retaining the geodetic directions. To benchmark our new package, we calculate the residual amplitude of the CMSE synthetics with respect to the reference synthetics calculated by SPECFEM3D_Globe. In the regional scale simulations with an area of 1300 km × 1300 km, we find a maximum of 5% amplitude residual for the SPECFEM3D_Cartesian synthetics using the mesh generated by the CMSE, much smaller than the maximum amplitude residual of 100% for the synthetics based on its built-in meshing tool. Therefore, our new meshing tool CMSE overcomes the limitations of the internal mesher used by SPECFEM3D_Cartesian and can be used for more accurate waveform simulations in larger regions beyond one UTM zone. Furthermore, CMSE can deal with regions at the south and north poles that cannot be handled by the UTM projection. Although other external code packages can be used to mesh the curvature of the Earth, the advantage of the CMSE code is that it is open-source, easy to use, and fully integrated with SPECFEM3D_Cartesian.

Statistical Tolerance Analysis With Sensitivities Established With Tolerance-Maps

2018 ◽  
Author(s):  
Aniket N. Chitale ◽  
Joseph K. Davidson ◽  
Jami J. Shah
Keyword(s):  
Tolerance Analysis ◽  
Minkowski Sum ◽  
Coordinate Frame ◽  
Target Feature ◽  
Functional Feature ◽  
Design Function ◽  
Statistical Tolerance ◽  
The One ◽  
The Relationship ◽  
Statistical Tolerance Analysis

The purpose of math models for tolerances is to aid a designer in assessing relationships between tolerances that contribute to variations of a dependent dimension that must be controlled to achieve some design function and which identifies a target (functional) feature. The T-Maps model for representing limits to allowable manufacturing variations is applied to identify the sensitivity of a dependent dimension to each of the contributing tolerances to the relationship. The method is to choose from a library of T-Maps the one that represents, in its own local (canonical) reference frame, each contributing feature and the tolerances specified on it; transform this T-Map to a coordinate frame centered at the target feature; obtain the accumulation T-Map for the assembly with the Minkowski sum; and fit a circumscribing functional T-Map to it. The fitting is accomplished numerically to determine the associated functional tolerance value. The sensitivity for each contributing tolerance-and-feature combination is determined by perturbing the tolerance, refitting the functional map to the accumulation map, and forming a ratio of incremental tolerance values from the two functional T-Maps. Perturbing the tolerance-feature combinations one at a time, the sensitivities for an entire stack of contributing tolerances can be built. For certain classes of loop equations, the same sensitivities result by fitting the functional T-Map to the T-Map for each feature, one-by-one, and forming the overall result as a scalar sum. Sensitivities help a designer to optimize tolerance assignments by identifying those tolerances that most strongly influence the dependent dimension at the target feature. Since the fitting of the functional T-Map is accomplished by intersection of geometric shapes, all the T-Maps are constructed with linear half-spaces.

An optimal trajectory planning method for path tracking of industrial robots

Robotica ◽  
2018 ◽  
Vol 37 (3) ◽  
pp. 502-520 ◽  
Author(s):  
Xianxi Luo ◽  
Shuhui Li ◽  
Shubo Liu ◽  
Guoquan Liu
Keyword(s):  
Trajectory Planning ◽  
Optimal Trajectory ◽  
Optimal Path ◽  
Path Tracking ◽  
Industrial Robots ◽  
Planning Method ◽  
Coordinate Frame ◽  
Optimization Approach ◽  
Cartesian Coordinate ◽  
Optimal Trajectory Planning

SUMMARYThis paper presents an optimal trajectory planning method for industrial robots. The paper specially focuses on the applications of path tracking. The problem is to plan the trajectory with a specified geometric path, while allowing the position and orientation of the path to be arbitrarily selected within the specific ranges. The special contributions of the paper include (1) an optimal path tracking formulation focusing on the least time and energy consumption without violating the kinematic constraints, (2) a special mechanism to discretize a prescribed path integration for segment interpolation to fulfill the optimization requirements of a task with its constraints, (3) a novel genetic algorithm (GA) optimization approach that transforms a target path to be tracked as a curve with optimal translation and orientation with respect to the world Cartesian coordinate frame, (4) an integration of the interval analysis, piecewise planning and GA algorithm to overcome the challenges for solving the special trajectory planning and path tracking optimization problem. Simulation study shows that it is an insufficient condition to define a trajectory just based on the consideration that each point on the trajectory should be reachable. Simulation results also demonstrate that the optimal trajectory for a path tracking problem can be obtained effectively and efficiently using the proposed method. The proposed method has the properties of broad adaptability, high feasibility and capability to achieve global optimization.

scholarly journals HESS Opinions "Integration of groundwater and surface water research: an interdisciplinary problem?"

2014 ◽  
Vol 11 (2) ◽  
pp. 2011-2044
Author(s):  
R. Barthel
Keyword(s):  
Surface Water ◽  
Hydrological Cycle ◽  
Regional Scale ◽  
Holistic Approach ◽  
Fully Integrated ◽  
Integration Schemes ◽  
Integrated Research ◽  
State Of Research ◽  
Interdisciplinary Theory ◽  
Similar Theory

Abstract. Today there is a great consensus that water resources research needs to become more holistic, integrating perspectives of a large variety of disciplines. Groundwater and surface water (hereafter: GW and SW) are typically identified as different compartments of the hydrological cycle and were traditionally often studied and managed separately. However, despite this separation, these respective fields of study are usually not considered to be different disciplines. They are often seen as different specialisations of hydrology with different focus, yet similar theory, concepts, methodology. The present article discusses how this notion may form a substantial obstacle in the further integration of GW and SW research and management. The article focusses on the regional scale (areas of approx. 103 to 106 km2), which is identified as the scale where integration is most greatly needed, but ironically the least amount of fully integrated research seems to be undertaken. The state of research on integrating GW and SW research is briefly reviewed and the most essential differences between GW hydrology (or hydrogeology, geohydrology) and SW hydrology are presented. Groundwater recharge and baseflow are used as examples to illustrate different perspectives on similar phenomena that can cause severe misunderstandings and errors in the conceptualisation of integration schemes. It is also discussed that integration of GW and SW research on the regional scale necessarily must move beyond the hydrological aspects, by collaborating with social sciences and increasing the interaction between science and the society in general. The typical elements of an ideal interdisciplinary workflow are presented and their relevance with respect to integration of GW and SW is discussed. The overall conclusions are that GW hydrology and SW hydrogeology study rather different objects of interest, using different types of observation, working on different problem settings. They have thus developed different theory, methodology and terminology. Yet, there seems to be a widespread lack of awareness of these differences which hinders the detection of the existing interdisciplinary aspects of GW and SW integration and consequently the development of truly unifying, interdisciplinary theory and methodology. Thus, despite having the ultimate goal of creating a more holistic approach, we should start integration by analysing potential disciplinary differences. Improved understanding among hydrologists of what interdisciplinary means and how it works is needed. Hydrologists, despite frequently being involved in multidisciplinary projects, are not sufficiently involved in developing interdisciplinary strategies and do usually not regard the process of integration as such as a research topic of its own. There seems to be a general reluctance to apply (truly) interdisciplinary methodology because this is tedious and few, immediate incentives are experienced.

scholarly journals Implementation of One-Stop Services Policy (PTSP) in North Jakarta City, DKI Jakarta Province

2020 ◽  
Vol 10 (2) ◽  
pp. 381
Author(s):  
Mary Ismowati ◽  
Ahmad Hidayat Rahadian ◽  
Muhammad Ali Massyhury ◽  
Muhammad Rafi Suryadi
Keyword(s):  
Information Technology ◽  
Human Resources ◽  
Fully Integrated ◽  
Online System ◽  
The North ◽  
Doing Business ◽  
One Stop ◽  
Ease Of Doing Business ◽  
The One ◽  
Research Show

The aim of the study was to obtain a formulation of the implementation of the One-Stop Services Policy (PTSP) in the North Jakarta Administrative City, namely the implementation of Perda No. 12 of 2013, and the Implementation of Presidential Regulation No. 91 of 2017 concerning the acceleration of ease of doing business through the implementation of an information technology-based licensing system (OSS). The research method used a qualitative approach by conducting interviews with a number of informants to determine the conditions and phenomena of the implementation of PTSP policies in North Jakarta. The research involved two research members from students in the framework of thesis research. The results of the research show that implementers have understood their duties and functions, but in the smooth running of their duties, they are constrained by a lack of human resources both in quantity and quality, support for information technology equipment that is not up to date, including the availability of information technology personnel at the district and sub-district levels. Then the OSS policy according to PP No. 24/2018 has not been fully effective, because it has not been fully integrated with the existing licensing system in PM-PTSP DKI Jakarta, namely JakEVO. The main obstacle to policy implementation, namely in terms of human resources, employee status has not been transferred to functional positions so that it affects career ranks and motivation. In addition, there is no HR competency standard for services, for online system services are not implemented according to target. The solution to overcome the obstacles conceptually has not been done.

scholarly journals First steps towards the assimilation of IASI ozone data into the MOCAGE-PALM system

2009 ◽  
Vol 9 (2) ◽  
pp. 6691-6737 ◽  
Author(s):  
S. Massart ◽  
C. Clerbaux ◽  
D. Cariolle ◽  
A. Piacentini ◽  
S. Turquety ◽  
...  
Keyword(s):  
Data Assimilation ◽  
Total Ozone ◽  
Transport Model ◽  
Polar Regions ◽  
Observation Error ◽  
Random Errors ◽  
Chemistry Transport Model ◽  
Ozone Data ◽  
The One ◽  
New Generation

Abstract. The Infrared Atmospheric Sounding Interferometer (IASI) is one of the five European new generation instruments carried by the polar-orbiting MetOp-A satellite. Data assimilation is a powerful tool to combine these data with a numerical model. This paper presents the first steps made towards the assimilation of the total ozone columns from the IASI measurements into a chemistry transport model. The IASI ozone data used are provided by an inversion of radiances performed at the LATMOS (Laboratoire Atmosphères, Milieux, Observations Spatiales). As a contribution to the validation of this dataset, the LATMOS-IASI data are compared to a four dimensional ozone field, with low systematic and random errors compared to ozonesondes and OMI-DOAS data. This field results from the combined assimilation of ozone profiles from the MLS instrument and of total ozone columns from the SCIAMACHY instrument. It is found that on average, the LATMOS-IASI data tends to overestimate the total ozone columns by 2% to 8%. The random observation error of the LATMOS-IASI data is estimated to about 6%, except over polar regions and deserts where it is higher. Using this information, the LATMOS-IASI data are then assimilated, combined with the MLS data. This first LATMOS-IASI data assimilation experiment shows that the resulting analysis is quite similar to the one obtained from the combined MLS and SCIAMACHY data assimilation.

Granite Coasts

2006 ◽  
Author(s):  
Piotr Migon
Keyword(s):  
Structural Adjustment ◽  
Regional Scale ◽  
Significant Proportion ◽  
Point Of View ◽  
Coastal Geomorphology ◽  
Coastal Morphology ◽  
The World ◽  
Coastal Landscapes ◽  
Coastal Scenery ◽  
The One

Although no estimate of the aggregate length of granite rock coasts around the world is available, they surely make up quite a significant proportion of the total, especially around the Fennoscandian and Canadian Shield (Bird and Schwartz, 1985). However, in contrast to the vast amount of literature about inland granite landforms, granite coastal scenery has attracted significantly less attention, in spite of the fact that some of the most spectacular coastal landscapes are supported by granite (Plate 6.1). Detailed studies of granite coastal geomorphology are surprisingly few, although the structural adjustment of the coastline in plan at the regional scale is a recurrent observation (Bird and Schwartz, 1985). One probable reason for this discrepancy between the length of granite coasts, their scenic values, and scientific knowledge are the low rates of geomorphic change expected along them. Therefore they are poor candidates for any process-oriented studies, which dominate contemporary coastal geomorphology. It is probably because of this scarcity of information that contrasting opinions have been expressed about the specifics of granite coasts. Whereas Twidale (1982: 2) asserts that: ‘In coastal contexts, too, the gross assemblage of forms is due to the processes operating there and not to properties peculiar to granites. . . . Orthogonal fracture sets also find marked expression but, with few exceptions, granite coasts are much the same as most others’; Trenhaile (1987: 173) goes on to say: ‘Igneous coasts are usually quite different from other rock coasts’. On the one hand, many granite coasts consist of an all-too-familiar assemblage of cliffs, coves, joint-aligned inlets, stacks, and sea arches. From this point of view, no components of coastal morphology are likely to be demonstrated to be unique to granite. But this is also true for granite landforms in general, as was indicated in the introduction to this book. On the other hand, there seems to be enough observational material to claim that certain granite coastal landforms have developed specific characteristics, different from those supported by other rocks, as well as that there exist certain very specific sections of granite coasts which hardly have parallels in other lithologies.

scholarly journals Atlantic hurricane surge response to geoengineering

2015 ◽  
Vol 112 (45) ◽  
pp. 13794-13799 ◽  
Author(s):  
John C. Moore ◽  
Aslak Grinsted ◽  
Xiaoran Guo ◽  
Xiaoyong Yu ◽  
Svetlana Jevrejeva ◽  
...  
Keyword(s):  
Radiative Forcing ◽  
Stratospheric Ozone ◽  
Storm Surges ◽  
Polar Regions ◽  
Global Mean Temperature ◽  
Intercomparison Project ◽  
Coastal Flood Risk ◽  
Atlantic Hurricanes ◽  
The One ◽  
The Tropics

Devastating floods due to Atlantic hurricanes are relatively rare events. However, the frequency of the most intense storms is likely to increase with rises in sea surface temperatures. Geoengineering by stratospheric sulfate aerosol injection cools the tropics relative to the polar regions, including the hurricane Main Development Region in the Atlantic, suggesting that geoengineering may mitigate hurricanes. We examine this hypothesis using eight earth system model simulations of climate under the Geoengineering Model Intercomparison Project (GeoMIP) G3 and G4 schemes that use stratospheric aerosols to reduce the radiative forcing under the Representative Concentration Pathway (RCP) 4.5 scenario. Global mean temperature increases are greatly ameliorated by geoengineering, and tropical temperature increases are at most half of those temperature increases in the RCP4.5. However, sulfate injection would have to double (to nearly 10 teragrams of SO2 per year) between 2020 and 2070 to balance the RCP4.5, approximately the equivalent of a 1991 Pinatubo eruption every 2 y, with consequent implications for stratospheric ozone. We project changes in storm frequencies using a temperature-dependent generalized extreme value statistical model calibrated by historical storm surges and observed temperatures since 1923. The number of storm surge events as big as the one caused by the 2005 Katrina hurricane are reduced by about 50% compared with no geoengineering, but this reduction is only marginally statistically significant. Nevertheless, when sea level rise differences in 2070 between the RCP4.5 and geoengineering are factored into coastal flood risk, we find that expected flood levels are reduced by about 40 cm for 5-y events and about halved for 50-y surges.

scholarly journals ZNACZENIE SAMORZĄDÓW W OCHRONIE ZABYTKÓW. PROPOZYCJE ZMIAN

2016 ◽  
pp. 71-76
Author(s):  
Małgorzata Gwiazdowska
Keyword(s):  
Local Government ◽  
Historic Preservation ◽  
State Government ◽  
Complete Solution ◽  
Regional Scale ◽  
Legal Regulations ◽  
Administration System ◽  
Legal Situation ◽  
Government Body ◽  
The One

Changes made to the administration system in Poland in the years 1989–1990 were aimed at decentralising state government and increasing the importance of local government bodies. The author of this article reckons that this idea has not been reflected in the Polish body of law yet. There are no legal regulations provided in the provisions of law – not only in terms of the legal situation of historic preservation offices but also with regard to deciding what should fall under the authority of local government bodies. Scope of duties of local government historic preservation officers working in separate offices should be similar to the one that individual departments have. Moreover, authority should no longer be granted on discretionary basis. A principle should be therefore formulated that everything what comes within the competence of historic preservation officers must comply with statutory legislation. If a local government body wants to be delegated either full or partial authority, it should prove that it has both organisational and financial capacity to exercise it. We should therefore work towards a complete solution which would be practical and possible to adopt on both state and regional scale.

scholarly journals Interannual variability of the Mediterranean trophic regimes from ocean color satellites

2015 ◽  
Vol 12 (17) ◽  
pp. 14941-14980 ◽  
Author(s):  
N. Mayot ◽  
F. D'Ortenzio ◽  
M. Ribera d'Alcalà ◽  
H. Lavigne ◽  
H. Claustre
Keyword(s):  
Spatial Distribution ◽  
Mediterranean Sea ◽  
Interannual Variability ◽  
Deep Convection ◽  
Regional Scale ◽  
Ocean Color ◽  
Run Off ◽  
The Mediterranean ◽  
The One ◽  
The Impact

Abstract. D'Ortenzio and Ribera d'Alcalà (2009, DR09 hereafter) divided the Mediterranean Sea into "bioregions" based on the climatological seasonality (phenology) of phytoplankton. Here we investigate the interannual variability of this bioregionalization. Using 16 years of available ocean color observations (i.e. SeaWiFS and MODIS), we analyzed the spatial distribution of the DR09 trophic regimes on an annual basis. Additionally, we identified new trophic regimes, with seasonal cycles of phytoplankton biomass different from the DR09 climatological description and named "Anomalous". Overall, the classification of the Mediterranean phytoplankton phenology proposed by DR09 (i.e. "No Bloom", "Intermittently", "Bloom" and "Coastal"), is confirmed to be representative of most of the Mediterranean phytoplankton phenologies. The mean spatial distribution of these trophic regimes (i.e. bioregions) over the 16 years studied is also similar to the one proposed by DR09. But at regional scale some annual differences, in their spatial distribution and in the emergence of "Anomalous" trophic regimes, were observed compared to the DR09 description. These dissimilarities with the DR09 study were related to interannual variability in the sub-basin forcing: winter deep convection events, frontal instabilities, inflow of Atlantic or Black Sea Waters and river run-off. The large assortment of phytoplankton phenologies identified in the Mediterranean Sea is thus verified at interannual level, confirming the "sentinel" role of this basin to detect the impact of climate changes on the pelagic environment.

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