Seismic approaches for structural studies of the Sudbury basin

Geophysics ◽  
1984 ◽  
Vol 49 (10) ◽  
pp. 1675-1689 ◽  
Author(s):  
Derbew Messfin ◽  
Wooil Moon
Keyword(s):  
Large Scale ◽  
Computing Time ◽  
Granite Gneiss ◽  
High Amplitude ◽  
Ore Deposits ◽  
Small Scale ◽  
Mining District ◽  
Seismic Velocities ◽  
Initial Stage ◽  
Scale Models

This study investigates the feasibility of applying seismic techniques in the search for ore deposits, with particular emphasis given to locating orebodies at great depths. The basic procedure followed was essentially an understanding of the forward problem, whereby the effects of the subsurface structure in a typical mining district were thoroughly studied. The initial stage of the study was devoted to determining the elastic parameters by laboratory measurement of seismic velocities and densities of core samples obtained from the Sudbury basin, Canada. By virtue of its ability to handle lateral as well as vertical inhomogeneities, fast computing time and flexibility, the asymptotic ray theory was judged to be more suitable for studying the effect of geologic structures typically found in the Sudbury basin. Both large‐scale and small‐scale models, representing actual geologic conditions in Sudbury, were constructed. The computed seismic response of the large‐scale models shows that the micropegmatite/oxide‐rich quartz gabbro and the mafic norite/granite gneiss contacts are characterized by substantially strong reflections, indicating that these two interfaces can serve as marker horizons in future seismic surveys. In the small‐scale models of mineralized structures, the sulfide body was outlined by a distinctly high amplitude of reflection. Both the traveltime and the dynamic characteristics of these models have features that are indicative of the presence of mineralized structures.

scholarly journals Modeling Emissions from Concentrated Sources into Large-Scale Models: Theory and apriori Testing

Atmosphere ◽  
2020 ◽  
Vol 11 (8) ◽  
pp. 863
Author(s):  
Roberto Paoli
Keyword(s):  
Large Scale ◽  
General Procedure ◽  
Chemical Transport ◽  
Reaction Rates ◽  
Small Scale ◽  
Background Concentrations ◽  
Transport Models ◽  
Chemical Transport Models ◽  
Scale Models ◽  
Effective Reaction

This paper presents a general procedure to incorporate the effects emissions from localized sources, such as aircraft or ship engines, into chemical transport models (CTM). In this procedure, the species concentrations in each grid box of a CTM are split into plume or small-scale concentrations and background concentrations, respectively, and the corresponding conservation equations are derived. The plume concentrations can be interpreted as subgrid contributions for the CTM grid-box averaged concentrations. The chemical reactions occurring inside the plume are parameterized by introducing suitable “effective” reaction rates rather than modifying the emission indices of the species inside the plume. Various methods for implementation into large-scale models are discussed that differ by the accuracy of the description of plume process. The mathematical consistency of the method is verified on simple idealized setting consisting of a reactive plume in homogeneous turbulence.

Empirical Studies on Demand Pull in Photovoltaic Sector of Twenty Countries

2013 ◽  
Vol 827 ◽  
pp. 451-456
Author(s):  
Mo Lin Huo ◽  
Bao Guo Shan
Keyword(s):  
Large Scale ◽  
Empirical Studies ◽  
Technical Innovation ◽  
Practical Significance ◽  
Small Scale ◽  
Market Growth ◽  
Demand Pull ◽  
Initial Stage ◽  
Acceleration Period ◽  
Diffusion Rates

High cost impedes large-scale deployment of photovoltaics (PV), and the technical innovation is one of most important factors of cost reduction, so how to accelerate the market pull for innovation has practical significance and theoretical value. This paper aims to analyze PV demand pull mechanism based on empirical evidence. According to the features of PV industry and technical innovation theories, make hypotheses of PV market pull and the relationship between diffusion rates and the market pull. Then propose testing method of the market pull and the coefficients assessing diffusion rates, and use historical data of twenty countries to conduct empirical studies. The testing results show that 70% of PV market in the twenty countries pulled technical innovation; at the initial stage of PV diffusion, the market pull was insignificant when the market kept at small scale and the diffusion rate can be indicated by the innovation coefficient; in the acceleration period, the market pull was insignificant when the market grew steeply and the rate can be indicated by the imitating coefficient. So in order to encourage demand pull, policy making is suggested to lead the market growth stable and sustained.

Large-Scale Analog Circuit Evolutionary Design Using a Real-Coded Scheme

2012 ◽  
Vol 220-223 ◽  
pp. 2036-2039
Author(s):  
Su Min Jiao ◽  
Cai Hong Wang ◽  
Xue Mei Wang
Keyword(s):  
Analog Circuits ◽  
Large Scale ◽  
Analog Circuit ◽  
Computing Time ◽  
Electronic System ◽  
Small Scale ◽  
Evolutionary Design ◽  
Continuous Space ◽  
Large Scale Problems ◽  
Circuit Representation

Analog circuits are of great importance in electronic system design. Recent evolutionary design results are usually small-scale analog circuits. This paper proposes a real-coded mechanism and uses it in the large-scale analog circuit evolutionary design. The proposed scheme evolves the circuit topology and size to a uniformed continuous space, in which the circuit representation is closed and of causality. Experimental results show that the proposed scheme can work successfully on many analog circuits with different kinds of characteristics. Comparing with other evolutionary methods before, the proposed scheme performs better on large-scale problems of circuit synthesis with higher search efficiency, lower computational complexity, and less computing time.

scholarly journals Pengembangan model permainan tradisional untuk membangun karakter pada siswa SD kelas atas

2017 ◽  
Vol 5 (2) ◽  
pp. 183 ◽  
Author(s):  
Puput Widodo ◽  
Ria Lumintuarso
Keyword(s):  
Large Scale ◽  
Relevant Literature ◽  
Field Studies ◽  
Development Stage ◽  
Small Scale ◽  
School Students ◽  
Educational Models ◽  
Central Java ◽  
Scale Models ◽  
The Media

Penelitian ini mengadaptasi penelitian dan pengembangan pendidikan model Borg & Gall dengan menyederhanakan menjadi 2 tahapan sebagai berikut (1) tahap pra-pengembangan, tahapan ini meliputi (a) kajian literatur dan penelitian relevan dan (b) studi lapangan, (2) tahap pengembangan, tahapan ini meliputi (a) penyusunan draf, (b) validasi ahli, (c) uji coba model skala kecil, (d) uji coba model skala besar, dan (e) produk akhir. Uji coba skala kecil dilakukan terhadap 30 anak kelas atas SDN Aditirto Pejagoan Kebumen, Provinsi Jawa Tengah. Uji coba skala besar dilakukan terhadap 130 anak kelas atas dari SD Negeri 1 Karangpoh, 26 siswa SD Negeri 1 Logede, 22 siswa SD Negeri 4 Pejagoan, 24 siswa SD Negeri 1 Kebulusan, dan 30 siswa SD Negeri 3 Kebulusan Kecamatan Pejagoan, Kabupaten Kebumen, Provinsi Jawa Tengah. Instrumen yang digunakan untuk mengumpulkan data adalah wawancara, kuisioner penilaian karakter permainan tradisional, kuisioner observasi pengembangan permainan tradisional, kuisioner observasi keefektifan model permainan tradisional, kuisioner penilian observasi ahli media, dan kuisioner evaluasi siswa. Hasil penelitian berupa pengembangan model permainan tradisional terdiri dari 3 jenis permainan yaitu: (1) permainan goteng, (2) lari papan/segi empat, dan (3) kasti tangan. Berdasarkan penilaian para ahli materi dan guru penjasorkes dapat disimpulkan bahwa pengembangan model permainan tradisional yang disusun sangat baik dan efektif, sehingga model permainan layak digunakan untuk pembelajaran pendidikan jasmani pada siswa kelas atas. Developing Models of Traditional Games to Build Characters of Elementary School Students of Upper Grades AbstractThe study was conducted through two stages by adapting the research and development of educational models Borg & Gall as follows (1) pre-development stage, this stage include (a) review of relevant literature and research, and (b) field studies, (2) the development stage, this stage include; (a) drafting, (b) validation expert, (c) testing of small-scale models, (d) testing large-scale models, and (e) of the final product.The small-scale tryout was conducted by involving 30 students of upper grades of state elementary schools (SES) of Aditirto, Pejagoan sub-district, Kebumen regency, Central Java porovinsi. The large-scale tryout was conducted by involving 130 students of upper grades of SES 1 of Karangpoh, 26 students of SES 1 of Logede, 22 students of SES 4 of Pejagoan, 24 students of SES 1 of Kebulusan, and 30 students of SES 3 of Kebulusan Pejagoan sub-district, Kebumen regency, Central Java porovinsi. The data collecting instruments were an interview guideline, a questionnaire to assess characters of traditional games, a questionnaire to assess the traditional game development, a questionnaire for the assessment by the media expert, and a questionnaire for the evaluation by students. The results of the study of the development of models of traditional games were three types of games, i.e: (1) goteng game, (2) board/rectangle running, and (3) hand kasti. Based on the assessment by the materials experts and the teachers of physical, sports, and health education, it could be concluded that the developed modals of traditional games were very good and effective so that they were appropriate to be used in the learning physical education for the students of upper grades.

scholarly journals Modelling erosion and deposition in geophysical granular mass flows

2021 ◽  
Vol 52 (1) ◽  
pp. 29-32
Author(s):  
Sylvain Viroulet ◽  
Chris Johnson ◽  
Nico Gray
Keyword(s):  
Debris Flows ◽  
Large Scale ◽  
Laboratory Experiments ◽  
Pyroclastic Flows ◽  
Small Scale ◽  
Snow Avalanches ◽  
Erosion And Deposition ◽  
Granular Rheology ◽  
Scale Models ◽  
Mass Flows

During hazardous geophysical mass flows, such as rock or snow avalanches, debris flows and volcanic pyroclastic flows, a continuous exchange of material can occur between the slide and the bed. The net balance between erosion and deposition of particles can drastically influence the behaviour of these flows. Recent advances in describing the non-monotonic effective basal friction and the internal granular rheology in depth averaged theories have enabled small scale laboratory experiments (see fig. 1) to be quantitatively reproduced and can also be implemented in large scale models to improve hazard mitigation.

Interdisciplinary data-constrained 3-D potential field modelling with IGMAS+

2021 ◽  
Author(s):  
Denis Anikiev ◽  
Hans-Jürgen Götze ◽  
Judith Bott ◽  
Angela Maria Gómez-García ◽  
Maria Laura Gomez Dacal ◽  
...  
Keyword(s):  
Large Scale ◽  
Spatial Scales ◽  
Geophysical Methods ◽  
Receiver Functions ◽  
Research Centre ◽  
Small Scale ◽  
Gravity And Magnetic ◽  
Structural Density ◽  
Scale Models

<p>We introduce a modelling concept for the construction of 3-D data-constrained subsurface structural density models at different spatial scales: from large-scale models (thousands of square km) to regional (hundreds of square km) and small-scale (tens of square km) models used in applied geophysics. These models are important for understanding the drivers of geohazards, for efficient and sustainable extraction of resources from sedimentary basins such as groundwater, hydrocarbons or deep geothermal energy, as well as for investigation of capabilities of long-term underground storage of gas and radioactive materials.</p><p>The modelling concept involves interactive fitting of potential fields (gravity and magnetics) and their derivatives within IGMAS+ (Interactive Gravity and Magnetic Application System), a well-known software tool with almost 40 years of development behind it. The core of IGMAS+ is the analytical solution of the volume integral for gravity and magnetic effects of homogeneous bodies, bounded by polyhedrons of triangulated model interfaces. The backbone model is constrained by interdisciplinary data, e.g. geological maps, seismic reflection and refraction profiles, structural signatures obtained from seismic receiver functions, local surveys etc. The software supports spherical geometries to resolve the first-order effects related to the curvature of the Earth, which is especially important for large-scale models.</p><p>Currently being developed and maintained at the Helmholtz Centre Potsdam – GFZ German Research Centre, IGMAS+ has a cross-platform implementation with parallelization of computations and optimized storage. The powerful graphical interface makes the interactive modelling and geometry modification process user-friendly and robust. Historically IGMAS+ is free for research and education purposes and has a long-term plan to remain so.</p><p>IGMAS+ has been used in various tectonic settings and we demonstrate its flexibility and usability on several lithospheric-scale case studies in South America and Europe.</p><p>Both science and industry are close to the goal of treating all available geoscientific data and geophysical methods inside a single subsurface model that aims to integrate most of the interdisciplinary measurement-based constraints and essential structural trends coming from geology. This approach presents challenges for both its implementation within the modelling software and the usability and plausibility of generated results, requiring a modelling concept that integrates the data methods in a feasible way together with recent advances in data science methods. As such, we present the future outlook of our modelling concept in regards to these challenges.</p>

Small-Scale Models for Testing Masonry Structures

2010 ◽  
Vol 133-134 ◽  
pp. 497-502 ◽  
Author(s):  
Alvaro Quinonez ◽  
Jennifer Zessin ◽  
Aissata Nutzel ◽  
John Ochsendorf
Keyword(s):  
Large Scale ◽  
Low Cost ◽  
Three Dimensional ◽  
Model Testing ◽  
Scale Model ◽  
Small Scale ◽  
Material Strength ◽  
Masonry Structures ◽  
Scale Models ◽  
Set Up

Experiments may be used to verify numerical and analytical results, but large-scale model testing is associated with high costs and lengthy set-up times. In contrast, small-scale model testing is inexpensive, non-invasive, and easy to replicate over several trials. This paper proposes a new method of masonry model generation using three-dimensional printing technology. Small-scale models are created as an assemblage of individual blocks representing the original structure’s geometry and stereotomy. Two model domes are tested to collapse due to outward support displacements, and experimental data from these tests is compared with analytical predictions. Results of these experiments provide a strong understanding of the mechanics of actual masonry structures and can be used to demonstrate the structural capacity of masonry structures with extensive cracking. Challenges for this work, such as imperfections in the model geometry and construction problems, are also addressed. This experimental method can provide a low-cost alternative for the collapse analysis of complex masonry structures, the safety of which depends primarily on stability rather than material strength.

Obtaining accurate pressure measurements in a stored granular medium

1992 ◽  
Vol 29 (2) ◽  
pp. 217-224 ◽  
Author(s):  
N. D. Jarrett ◽  
C.J. Brown ◽  
D.B. Moore
Keyword(s):  
Experimental Error ◽  
Granular Media ◽  
Large Scale ◽  
Reliable Data ◽  
Small Scale ◽  
Pressure Measurements ◽  
Placement Method ◽  
Scale Models ◽  
Scale Test ◽  
Media Pressure

The project is concerned with the acquisition of reliable data from large-scale silos, and in particular data relating to pressures imposed on the silo by the stored material. For the purposes of the study a square plan-form steel silo was used, and the stored material was Leighton Buzzard sand. The experimental work was carried out in the environmentally controlled conditions of the laboratories at Building Research Establishment, Watford, United Kingdom. The project adopted the pressure cells designed by V. Askegaard. Both wall cells and embedded cells were used to measure pressure at the interface of the wall and stored material and within the stored material, respectively. For the embedded cells, it has been shown that the installation procedure is critical in obtaining reliable results. Preliminary tests were carried out in small-scale models until confidence in repeatability of the placement method was achieved. Even then there was some variation in results, and to ensure confidence each large-scale test was repeated five times. Pressures measured by both wall and embedded cells were compared to obtain calibration factors, and then the overall vertical equilibrium of the model was checked and found to be within the bounds of experimental error. The authors are confident of the accuracy of data which can now be achieved provided care is taken with both installation procedures and calibration checks. Key words : pressure measurement, silos, granular media, pressure cell calibration.

scholarly journals OPTIMAL POLICY IN RATIONAL EXPECTATIONS MODELS: NEW SOLUTION ALGORITHMS

2007 ◽  
Vol 11 (1) ◽  
pp. 31-55 ◽  
Author(s):  
RICHARD DENNIS
Keyword(s):  
Business Cycle ◽  
Optimal Policy ◽  
Rational Expectations ◽  
Large Scale ◽  
New Keynesian ◽  
Small Scale ◽  
Structural Form ◽  
Optimization Constraints ◽  
Solution Algorithms ◽  
Scale Models

This paper develops methods to solve for optimal discretionary policies and optimal commitment policies in rational expectations models. These algorithms, which allow the optimization constraints to be conveniently expressed in second-order structural form, are more general than existing methods and are simple to apply. We use several New Keynesian business cycle models to illustrate their application. Simulations show that the procedures developed in this paper can quickly solve small-scale models and that they can be usefully and effectively applied to medium- and large-scale models.

scholarly journals A reductionist approach to model photosynthetic self-regulation in eukaryotes in response to light

2015 ◽  
Vol 43 (6) ◽  
pp. 1133-1139 ◽  
Author(s):  
Anna Matuszyńska ◽  
Oliver Ebenhöh
Keyword(s):  
Large Scale ◽  
Metabolic Networks ◽  
Self Regulation ◽  
Redox Balance ◽  
Biological Data ◽  
Small Scale ◽  
Photosynthetic Organisms ◽  
Genome Wide ◽  
Scale Models ◽  
Reductionist Approach

Along with the development of several large-scale methods such as mass spectrometry or micro arrays, genome wide models became not only a possibility but an obvious tool for theoretical biologists to integrate and analyse complex biological data. Nevertheless, incorporating the dynamics of photosynthesis remains one of the major challenges while reconstructing metabolic networks of plants and other photosynthetic organisms. In this review, we aim to provide arguments that small-scale models are still a suitable choice when it comes to discovering organisational principles governing the design of biological systems. We give a brief overview of recent modelling efforts in understanding the interplay between rapid, photoprotective mechanisms and the redox balance within the thylakoid membrane, discussing the applicability of a reductionist approach in modelling self-regulation in plants and outline possible directions for further research.

Sign in / Sign up

Export Citation Format

Share Document