Fundamentals of Rock Physics

2021 ◽  
Author(s):  
Nikolai Bagdassarov
Keyword(s):  
Rock Physics ◽  
Theoretical Models ◽  
Petroleum Engineering ◽  
Graduate Courses ◽  
Short Introduction ◽  
Mineral Physics ◽  
Rock Density ◽  
Upper Level ◽  
Underlying Processes ◽  
Physical Principles

Rock physics encompasses practically all aspects of solid and fluid state physics. This book provides a unified presentation of the underlying physical principles of rock physics, covering elements of mineral physics, petrology and rock mechanics. After a short introduction on rocks and minerals, the subsequent chapters cover rock density, porosity, stress and strain relationships, permeability, poroelasticity, acoustics, conductivity, polarizability, magnetism, thermal properties and natural radioactivity. Each chapter includes problem sets and focus boxes with in-depth explanations of the physical and mathematical aspects of underlying processes. The book is also supplemented by online MATLAB exercises to help students apply their knowledge to numerically solve rock physics problems. Covering laboratory and field-based measurement methods, as well as theoretical models, this textbook is ideal for upper-level undergraduate and graduate courses in rock physics. It will also make a useful reference for researchers and professional scientists working in geoscience and petroleum engineering.

Research on Upper Level Drug Trafficking: A Review

2007 ◽  
Vol 37 (4) ◽  
pp. 827-844 ◽  
Author(s):  
Frederick Desroches
Keyword(s):  
Organized Crime ◽  
Drug Trafficking ◽  
Theoretical Models ◽  
Friendship Networks ◽  
Drug Markets ◽  
Niche Markets ◽  
Low Profile ◽  
Upper Level ◽  
Drug Traffickers ◽  
The Uk

This article examines research on upper level drug traffickers in the U.S., the UK, Canada, and the Netherlands. Included is an analysis and critique of typologies of drug traffickers and theoretical models of organized crime as they apply to upper level drug networks. Studies of higher level drug trafficking indicate that drug markets represent informal and loosely organized associations of relatively small syndicates or crews of independent drug entrepreneurs. They compete for market share and deal primarily or exclusively with trusted associates chosen from ethnic, kinship, and friendship networks. Most dealers are highly cautious, eschew the use of violence, typically make huge profits, attempt to maintain a low profile, rationalize their conduct as business activity, and operate within geographically niche markets.

Getting back on track: change management at AfrobitLink Ltd

2017 ◽  
Vol 13 (1) ◽  
pp. 120-151
Author(s):  
Olugbenga Adeyinka ◽  
Mary Kuchta Foster
Keyword(s):  
Change Management ◽  
Organizational Behavior ◽  
Attribution Theory ◽  
International Management ◽  
Rapid Expansion ◽  
Field Analysis ◽  
Graduate Courses ◽  
Content Type ◽  
Upper Level ◽  
Management Theories

Synopsis AfrobitLink Ltd was an information technology (IT) firm with headquarters in Lagos, Nigeria. AfrobitLink started as a very small IT firm with less than two dozen staff. Within a few years of its founding, AfrobitLink established itself as a dependable organization known for delivering high-quality IT services. However, starting in 2004, AfrobitLink experienced rapid growth as it expanded to serve the telecommunications firms taking advantage of the deregulated market. This rapid expansion resulted in many challenges for AfrobitLink. The firm rapidly expanded into all 36 states in Nigeria, hiring a manager to oversee the company’s operations in each of the states. Poor hiring practices, inadequate training, excessive spans of control, low accountability, a subjective reward system, and other cultural issues, such as a relaxed attitude to time, resulted in low motivation, high employee turnover, poor customer service, and financial losses. By 2013, the firm was operating at a loss and its reputation was in shambles. Generally, the culture was toxic: employees did not identify with the firm or care about its goals, there were no performance standards, employees were not held accountable, self-interest and discrimination prevailed. The organization was in a downward spiral. Consultants were hired to help sort out the firm’s problems but these efforts yielded few results. Ken Wilson, the founder’s son, was hired in 2014 as VP of Administration to help get the firm back on track. As a change agent, Ken had to decide how to address the issues facing the firm and how to achieve profitable growth. Research methodology Primary sources included interviews with the company CEO, his wife, his son, and a volunteer staff member. Secondary sources included the company website. The names of the people and the firm in the case have been changed to provide anonymity. Relevant courses and levels This case is intended for use in graduate courses (although it can also be used in upper level undergraduate courses) in change management/organization development, organizational behavior, leadership, or international management. For graduate courses, students may focus on application or integration of several theories or concepts. For upper level undergraduate courses, students may focus on application of a single theory or concept. Below are suggested texts or readings for each type of student by subject. Theoretical bases Change management theories (e.g. Lewin’s force field analysis (Schein, 1996), Kotter’s eight-step change management process (Kotter, 2007), The change kaleidoscope approach (Balogun and Hailey, 2008)), social identity theory (Tajfel, 1981), attribution theory (Kelley, 1972), leadership theories (e.g. Hersey and Blanchard, 1969), intercultural/international management theories (e.g. Hofstede, 1980, 1991).

Transport in Highly Heterogeneous Porous Media: From Direct Simulation to Macro-Scale Two-Equation Models or Mixed Models

2008 ◽  
Vol 3 (1) ◽  
Author(s):  
Debenest Gérald ◽  
Michel Quintard
Keyword(s):  
Porous Media ◽  
Mixed Models ◽  
Large Scale ◽  
Chemical Engineering ◽  
Heterogeneous Media ◽  
Theoretical Models ◽  
Heterogeneous Porous Media ◽  
Petroleum Engineering ◽  
Direct Simulation ◽  
Macro Scale

Flows in highly heterogeneous porous media are found in many practical fields, such as hydrology, petroleum engineering, and chemical engineering. The case of two-region heterogeneous media (fractured media, catalytic beds, etc.) plays a fundamental role. The different questions associated with this specific case are illustrated in this paper for two different kinds of transport: (i) flow of a slightly compressible fluid, (ii) dispersion of a tracer. Many different theoretical models are implemented using COMSOL Multiphysics™. These models correspond to direct simulation and macro-scale or large-scale models such as fully averaged models or mixed models.

scholarly journals Zonal scale and temporal variability of the Asian monsoon anticyclone in an idealised numerical model

2021 ◽  
Author(s):  
Philip Rupp ◽  
Peter Haynes
Keyword(s):  
Temporal Variability ◽  
Baroclinic Instability ◽  
Thermal Relaxation ◽  
Theoretical Models ◽  
Analysis Data ◽  
Zonal Scale ◽  
Mean Structure ◽  
Upper Level ◽  
Background State ◽  
Eddy Shedding

Abstract. The upper-level monsoon anticyclone is studied in a 3-D dry dynamical model as the response of a background circulation without any imposed zonal structure to a steady imposed zonally confined heat source. The characteristics of the background circulation are determined by thermal relaxation towards a simple meridionally varying state, which gives rise to baroclinic instability if meridional gradients are sufficiently large. This model configuration allows study of the dependence of the monsoon anticyclone response on characteristics of both the imposed heating and the background state, in particular including interactions between the anticyclone and the active dynamics on its poleward side in the form of the jet and baroclinic eddies. As characteristics of forcing and background state are varied a range of different behaviours emerges, many of which strongly resemble phenomena and features associated with the monsoon anticyclone as observed in re-analysis data. For a resting background state the time-mean anticyclone is highly extended in longitude to the west of the forcing region. When the active mid-latitude dynamics is included the zonal extent of the time-mean anticyclone is limited, without any need for the explicit upper-level momentum dissipation which is often included in simple theoretical models, but difficult to justify physically. We further describe in detail the spontaneous emergence of temporal variability in the form of westward eddy shedding from the monsoon anticyclone for varying strength of the imposed heating. By varying the strength of the background mid-latitude dynamics we observe a transition of the system from a state with periodic westward eddy shedding to a state dominated by eastward shedding. The details of the time-mean structure and temporal evolution depend on the structure of the background flow and for certain flows the monsoon anticyclone shows signs of both westward and eastward shedding.

scholarly journals Implementing A Business Intelligence (BI)/Corporate Performance Management (CPM) Solution: Challenges Faced By A Major National Retailer

2017 ◽  
Vol 13 (2) ◽  
pp. 63-72
Author(s):  
Andrew D. Schiff ◽  
Mark T. Warren
Keyword(s):  
Information Technology ◽  
Project Management ◽  
Performance Management ◽  
Business Intelligence ◽  
Corporate Performance ◽  
Accounting Information ◽  
Graduate Courses ◽  
Accounting Information Systems ◽  
Upper Level ◽  
Technology Solution

Based on actual events, this case is concerned with the practical and managerial challenges associated with analyzing, designing and implementing a Business Intelligence (BI) / Corporate Performance Management (CPM)information technology solution in a large national retailer. Secondary issues examined include strategy, project management and conflict resolution. This case is appropriate for upper-level undergraduate and masters-level graduate courses in information technology, accounting information systems and project management. It is designed to be taught in about one class hour, and requires four to six hours of outside preparation by students. 

Investigating the influence of mineralogy and pore shape on the velocity of carbonate rocks: Insights from extant global data sets

2015 ◽  
Vol 3 (1) ◽  
pp. SA15-SA31 ◽  
Author(s):  
Mark G. Kittridge
Keyword(s):  
Elastic Properties ◽  
Rock Physics ◽  
Theoretical Models ◽  
P Wave ◽  
Data Sets ◽  
Pore Shape ◽  
Data Set ◽  
S Waves ◽  
Extreme Variability ◽  
Global Data

Using a variety of recent public-domain data sets comprising porosity, velocity (P- and S-waves), and, in most cases, mineralogy and petrographic data, I created an extensive global data set and evaluated the importance of mineralogy and pore type on the elastic properties behavior of carbonate core plugs. Results from this investigation clearly illuminated the potential for overinterpreting elastic properties behavior as a function of pore type(s) when mineralogy was not explicitly included in the analysis. Rock-physics analysis using a combination of heuristic and theoretical models illustrated that mineralogy exerted a significant additional variation on velocity at a given porosity. Failure to account for mineralogy exacerbated inferences about the effect of pore type(s) made using a comparison of P-wave velocity to an inappropriate empirical model (Wyllie) that did not account for pore shape(s). In this analysis, extreme variability in carbonate velocity was observed in only portions of two data sets, when mineralogy was explicitly considered and robust models that accounted for inclusion (pore) shape were used. Results from this analysis resulted in a recommended workflow, including a rock-physics template and dry-rock modulus diagnostics, for the evaluation of lab-based carbonate rock-physics data. The workflow was amenable to further integration with well-based data and other core-based petrophysical measurements (e.g., electrical properties).

scholarly journals Geomechanical Upscaling Methods: Comparison and Verification via 3D Printing

Energies ◽  
2019 ◽  
Vol 12 (3) ◽  
pp. 382 ◽  
Author(s):  
Lingyun Kong ◽  
Mehdi Ostadhassan ◽  
Siavash Zamiran ◽  
Bo Liu ◽  
Chunxiao Li ◽  
...  
Keyword(s):  
Multiple Scales ◽  
Triaxial Compression ◽  
Rock Physics ◽  
Petroleum Engineering ◽  
Compression Tests ◽  
Geomechanical Properties ◽  
Rock Fragments ◽  
Rock Types ◽  
3D Printed ◽  
Comparison Of The Results

Understanding geomechanical properties of rocks at multiple scales is critical and relevant in various disciplines including civil, mining, petroleum and geological engineering. Several upscaling frameworks were proposed to model elastic properties of common rock types from micro to macroscale, considering the heterogeneity and anisotropy in the samples. However, direct comparison of the results from different upscaling methods remains limited, which can question their accuracy in laboratory experiments. Extreme heterogeneity of natural rocks that arises from various existing components in them adds complexity to verifying the accuracy of these upscaling methods. Therefore, experimental validation of various upscaling methods is performed by creating simple component materials, which is, in this study, examining the predicted macroscale geomechanical properties of 3D printed rocks. Nanoindentation data were first captured from 3D printed gypsum powder and binder rock fragments followed by, triaxial compression tests on similar cylindrical core plugs to acquire modulus values in micro and macroscale respectively. Mori-Tanaka (MT) scheme, Self-Consistent Scheme (SCS) method and Differential Effective Medium (DEM) theory were used to estimate Young’s modulus in macroscale based on the results of nanoindentation experiments. The comparison demonstrated that M-T and SCS methods would provide us with more comparable results than DEM method. In addition, the potential applications of 3D printed rocks were also discussed regarding rock physics and the geomechanics area in petroleum engineering and geosciences.

Nokia OYJ: Financing the WP Strategic Plan

2017 ◽  
pp. 1-25
Author(s):  
Susan Chaplinsky ◽  
Felicia C. Marston
Keyword(s):  
Product Innovation ◽  
Credit Rating ◽  
Strategic Change ◽  
Strategic Plan ◽  
Careful Consideration ◽  
Financial Resources ◽  
Graduate Courses ◽  
Student Preparation ◽  
Upper Level

The Nokia case provides an opportunity to explore financing alternatives in a situation of broad strategic change. The case emphasizes the difficulties of managing the financial resources of technology-based companies when they fall behind in product innovation. Nokia, the world's leading producer of mobile phones, had recently seen its market share and profits eroded by rival products such as Apple's iPhone and phones featuring Google's Android operating system. In February 2011, Nokia CEO Stephen Elop announced a strategic plan and partnership with Microsoft to have Windows serve as its primary OS for smartphones. Since that announcement, Nokia reported a net loss in earnings, followed by a downgrade of its credit rating in the summer of 2012.Analysts regard the next two years as a period of great uncertainty for the company. In January 2012, the CFO of Nokia estimates that the firm might require up to EUR4.3 billion in funding over the next two years to implement the plan under a representative downside scenario. Students are asked to evaluate the tradeoffs of raising the funds by issuing long-term debt, issuing equity, cutting dividends, or reducing cash. Given the firm's recent competitive struggles, none of the options is particularly appealing, which forces careful consideration of tradeoffs.The Nokia is appropriate for use in upper-level undergraduate and graduate courses covering topics in capital raising, capital structure, corporate finance, and the costs of financing. A spreadsheet file of case exhibits to facilitate student preparation, teaching note, and instructional spreadsheet file are available for the case.

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