Transient response of an induction logging tool in a borehole

Geophysics ◽  
1981 ◽  
Vol 46 (9) ◽  
pp. 1291-1300 ◽  
Author(s):  
W. C. Chew ◽  
S. Gianzero ◽  
K. J. Kaplin
Keyword(s):  
Transient Response ◽  
Simple Algorithm ◽  
Induction Logging ◽  
Vertical Magnetic Dipole ◽  
Long Time ◽  
Double Fourier Transform ◽  
The Difference ◽  
Direct Numerical Integration ◽  
Homogeneous Formation ◽  
Logging Tool

The long time transient response is developed for a point coil transmitter (vertical magnetic dipole) located in a wellbore surrounded by a homogeneous formation. A simple algorithm is derived for the apparent conductivity signal based on the difference between the voltage nulls in a pair of receiver coils which are displaced vertically from the transmitter along the axis of the wellbore. A justification of these results is provided by means of a direct numerical integration (double Fourier transform) and also two separate approximate approaches.

Inter-country inequality as a dynamic process and the problem of post-industrial development

2018 ◽  
pp. 5-29 ◽  
Author(s):  
L. M. Grigoryev ◽  
V. A. Pavlyushina
Keyword(s):  
Economic Growth ◽  
Political Institutions ◽  
Industrial Development ◽  
Modern World ◽  
New Approach ◽  
Development Level ◽  
The World ◽  
Long Time ◽  
The Difference ◽  
Post Industrial

The phenomenon of economic growth is studied by economists and statisticians in various aspects for a long time. Economic theory is devoted to assessing factors of growth in the tradition of R. Solow, R. Barrow, W. Easterly and others. During the last quarter of the century, however, the institutionalists, namely D. North, D. Wallis, B. Weingast as well as D. Acemoglu and J. Robinson, have shown the complexity of the problem of development on the part of socioeconomic and political institutions. As a result, solving the problem of how economic growth affects inequality between countries has proved extremely difficult. The modern world is very diverse in terms of development level, and the article offers a new approach to the formation of the idea of stylized facts using cluster analysis. The existing statistics allows to estimate on a unified basis the level of GDP production by 174 countries of the world for 1992—2016. The article presents a structured picture of the world: the distribution of countries in seven clusters, different in levels of development. During the period under review, there was a strong per capita GDP growth in PPP in the middle of the distribution, poverty in various countries declined markedly. At the same time, in 1992—2016, the difference increased not only between rich and poor groups of countries, but also between clusters.

Psychology: Volume 5

2019 ◽  
Keyword(s):  
World View ◽  
Science Volume ◽  
Western World ◽  
Mental Life ◽  
Long Time ◽  
The Difference ◽  
New Perspective ◽  
Indian Setting ◽  
The Mind ◽  
The Relationship

This survey of research on psychology in five volumes is a part of a series undertaken by the ICSSR since 1969, which covers various disciplines under social science. Volume Five of this survey, Explorations into Psyche and Psychology: Some Emerging Perspectives, examines the future of psychology in India. For a very long time, intellectual investments in understanding mental life have led to varied formulations about mind and its functions across the word. However, a critical reflection of the state of the disciplinary affairs indicates the dominance of Euro-American theories and methods, which offer an understanding coloured by a Western world view, which fails to do justice with many non-Western cultural settings. The chapters in this volume expand the scope of psychology to encompass indigenous knowledge available in the Indian tradition and invite engaging with emancipatory concerns as well as broadening the disciplinary base. The contributors situate the difference between the Eastern and Western conceptions of the mind in the practice of psychology. They look at this discipline as shaped by and shaping between systems like yoga. They also analyse animal behaviour through the lens of psychology and bring out insights about evolution of individual and social behaviour. This volume offers critique the contemporary psychological practices in India and offers a new perspective called ‘public psychology’ to construe and analyse the relationship between psychologists and their objects of study. Finally, some paradigmatic, pedagogical, and substantive issues are highlighted to restructure the practice of psychology in the Indian setting.

LONG‐TIME RESPONSE PREDICTED BY EXACT ELASTIC RAY THEORY

Geophysics ◽  
1965 ◽  
Vol 30 (3) ◽  
pp. 363-368 ◽  
Author(s):  
T. W. Spencer
Keyword(s):  
Formal Solution ◽  
Intermediate Stage ◽  
Time Limit ◽  
Time Interval ◽  
Individual Response ◽  
Axially Symmetric ◽  
Long Time ◽  
The Difference ◽  
The Individual ◽  
Significant Figures

The formal solution for an axially symmetric radiation field in a multilayered, elastic system can be expanded in an infinite series. Each term in the series is associated with a particular raypath. It is shown that in the long‐time limit the individual response functions produced by a step input in particle velocity are given by polynomials in odd powers of the time. For rays which suffer m reflections, the degree of the polynomials is 2m+1. The total response is obtained by summing all rays which contribute in a specified time interval. When the rays are selected indiscriminately, the difference between the magnitude of the partial sum at an intermediate stage of computation and the magnitude of the correct total sum may be greater than the number of significant figures carried by the computer. A prescription is stated for arranging the rays into groups. Each group response function varies linearly in the long‐time limit and goes to zero when convolved with a physically realizable source function.

Study of the Cause of Lost Circulation while Drilling Fractured Carbonates

2021 ◽  
Author(s):  
Alexey Ruzhnikov
Keyword(s):  
Success Rate ◽  
Drilling Fluid ◽  
Circulation Zone ◽  
Lost Circulation ◽  
Carbonate Formation ◽  
New Information ◽  
Fractured Carbonate ◽  
Long Time ◽  
The Difference ◽  
Fractured Carbonates

Abstract Fractured carbonate formations are prone to lost circulation, which affects the well construction process and has longtime effect on well integrity. Depending on the nature of losses (either induced or related to local dissolutions) the success rate is different when the induced losses can be cured with a high chance, and the one related to dissolutions may take a long time, and despite multiple attempts, the success rate is normally low. To have a better understanding of the complete losses across the fractured carbonates, a series of studies were initiated. First, to understand the strength of the loss zone, the fracture closing pressure was evaluated studying the fluid level in the annulus and back-calculating the effect of drilling fluid density. Second, the formation properties across the loss circulation zones were studied using microresistivity images, dip data, and imaging of fluid-saturated porous media. The results of the studies brought a lot of new information and explained some previous mysteries. The formation strength across the lost circulation zone was measured, and it was confirmed that it remains constant despite other changes of the well construction parameters. Additionally, it was confirmed that the carbonates are naturally highly fractured, having over 900 fractures along the wellbore. The loss circulation zone was characterized, and it was confirmed that the losses are not related to the fractures but rather to the karst, dissolution, and megafractures. The size and dip of the fractures were identified, and it was proven the possibility to treat them with conventional materials. However, the size of identified megafractures and karst zones exceeding the fractures by 10 times in true vertical depth, and in horizontal wells the difference is even higher due to measured depth. This new information helps to explain the previous unsuccessful attempts with the conventional lost circulation materials. The manuscript provides new information on the fractured carbonate formation characterization not available previously in the literature. It allows to align the subsurface and drilling visions regarding the nature of the losses and further develop the curing mechanisms.

scholarly journals Surgical Management of Benign Gastric Tumors: A Review

2021 ◽  
pp. 420-426
Author(s):  
Hashem Bark Awadh Abood ◽  
Amani Nasser D. Albalawi ◽  
Haifa Obedullah AlEnazi ◽  
Mousa Mutlaq Almuhanna ◽  
Norah Othman Busaad ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Gastrointestinal Stromal Tumors ◽  
Laparoscopic Resection ◽  
Benign Tumors ◽  
Stromal Tumors ◽  
Gastric Tumors ◽  
Laparoscopic Excision ◽  
Long Time ◽  
The Difference ◽  
Stomach Epithelium

Benign stomach and duodenal tumors are uncommon. Any component of the stomach epithelium, whether glandular, endocrine, or mesenchymal, can develop benign neoplastic tumors. The majority of people with benign stomach and duodenal tumors are asymptomatic for a long time. When symptoms do appear, they are determined by the tumor's size, location, and comorbidities. Endoscopy, computed tomography, and especially endoscopic ultrasonography results are used diagnose. Clinically, it's difficult to tell the difference between benign and malignant stomach tumors. Even benign tumors can undergo malignant transformation, severe obstructive problems, and bleeding. As a result, aggressive surgical resection of the tumors should be undertaken. Laparoscopic resection has become the first option of many surgeons since the development of minimally invasive surgery. According to previous literature, laparoscopic excision of GIST is safe and effective. In this review we’ll be looking at benign gastric tumors, gastrointestinal stromal tumors (GISTs) and their diagnosis.

scholarly journals WAVE RECORDING ON THE IJSSELMEER

2011 ◽  
Vol 1 (7) ◽  
pp. 3
Author(s):  
P. W. Roest
Keyword(s):  
Average Period ◽  
Recording Time ◽  
Ice Drift ◽  
Recording Station ◽  
Long Time ◽  
Wave Heights ◽  
Wave Research ◽  
The Difference ◽  
Hydraulics Laboratory ◽  
The Waves

The dimensions of the dikes in the Ijsselmeer are mainly determined by wave-attack. The dimensions of the waves as a result of the design gale are calculated with the diagram of the Hydraulics Laboratory at Delft (ref« 1). This diagram is based on data of Sverdrup for deep water and principally on laboratory studies for shallow water. For a long time there has been a need of wave recordings on the lake in order to verify the calculated wave heights. A problem is the impossibility of maintaining a permanent recording station on the lake due to ice-drift in wintertime. Otherwise the Ijsselmeer lends itself admirably to wave-research, because there are vast regions with only small variations in waterdepth. Another advantage is that frequently more or less stationary conditions will occur under the influence of winds of constant force and direction. When Dr. Dorrestein of the Royal Dutch Meteorological Institute introduced his new floating waverecorder, it was possible to take observations in every place of the lake. Soon it appeared that this recorder has many advantages. The equipment consists of an accelerometer mounted on a little raft of one meter each way, that follows the movement of the water surface. The signal of the accelerometer is transmitted by an electric cable to the ship, where it is double integrated and then recorded (ref. 3). During the last winter several observations have been carried out with an instrument of this type* As a result of initial troubles with the electronic equipment the number of observations during gale-conditions has been limited. The usual duration of each recording is about 15 minutes. The average period of the waves lies between three and a half and five seconds, so each diagram consists of 180 to 250 waves. Wave height is measured as the difference in height between a trough and the next crest. The average period is determined by dividing the total recording time by half the number of zerocrossings.

Enhancing the operating range of the multicomponent induction logging tool

2003 ◽  
Author(s):  
Berthold F. Kriegshäuser ◽  
André Santos ◽  
Liming Yu
Keyword(s):  
Operating Range ◽  
Induction Logging ◽  
Logging Tool

Phrazeography and lexicography: divergency in terminology

2019 ◽  
pp. 359-365
Author(s):  
Tetiana Tsymbaliuk-Skopnenko
Keyword(s):  
Scientific Literature ◽  
Critical Mass ◽  
Word Formation ◽  
Scientific Field ◽  
Separate Branch ◽  
Semantic Concepts ◽  
Long Time ◽  
New Ideas ◽  
The Difference ◽  
Definition Of

The term divergence is used traditionally in linguistics in origin of language and dialectology to denote the distinction between certain idioms. However, the unit under consideration was used in a wider context, because it denotes the process and the consequence that are caused by the distinction of features and properties of objects – something that ultimately leads to the division of the previously indistinguishable, and hence the appearance of new ideas about the world. In word formation, divergence is understood as the differentiation of common-root derivatives in terms of content or peculiarities of their use. Researchers also use the notions of semantic divergence – the difference in the content structure of derivative units with certain semantic nuances, which shows their semantic non-identity. Phraseography – conventionally derivative unit of lexemy lexicography, in this case we must talk about creating the first term by model of the second. For a long time in the scientific literature lexicography was used to refer to the section of linguistics, within which, with the help of certain methods, both lexemes and phraseologisms are described, although these units have different nature. The growth of phraseology as a separate scientific field did not automatically lead to the fixing of the term phrazeography in the national scientific discourse. Modern search engines on the Internet provide information that in this network found over a thousand documents in the Ukrainian language, which includes the word phrazeography. Certainly, this cannot be an example of the frequency of the use of this lexeme, but this fact suggests that in the modern scientific world there is a critical mass for understanding of the phrazeography as a separate scientific field. Some important arguments against this tendency were not found, although in modern university textbook phrazeography information is presented in the section “Phraseology” or at the end of “Lexicsology”, while lexicography as a separate branch, not within the limits of lexicology, has long been entrenched in the educational and scientific literature. And it sounds paradoxical to a certain extent, because it is from phraseology (however, in symbiosis with lexicography), not only the newest Ukrainian phraseology as a science began, the description of phraseological units was one of the first tasks of Ukrainian vocabulary in general. In addition, we note that the term “science about dictionaries” is most often used in the sense of “lexicography”. Since the tradition of non-differentiation of lexicography and phraseology is very strong, it would be expedient (and simply convenient) to use this Ukrainian term for the definition of synthetic understanding of the two branches of philology as a related unity: lexicography (theoretical and practical) and phrazeography (also theoretical and practical). If we accept such a proposal, then there will be no unnecessary confrontation between lexicography and phrazeography, the uncertainty of which leads to many misunderstandings. We can conclude that there is no reason to denote by the term lexicography the whole set of scientific approaches related to the phrazeography description. In Ukrainian linguistics, it is necessary to clearly delineate the terms lexicography and phrazeography, since they, over the last time, consolidated various semantic concepts.

Characterization of dogfish gastric mucosa under hyperbaric conditions

1983 ◽  
Vol 245 (2) ◽  
pp. G236-G241
Author(s):  
G. W. Kidder
Keyword(s):  
Gastric Mucosa ◽  
Transient Response ◽  
Partial Pressure Of Oxygen ◽  
Urea Content ◽  
Current Voltage ◽  
Current Passage ◽  
Long Time ◽  
Voltage Clamping ◽  
Hyperbaric Conditions

Using hyperbaric conditions previously shown to give improved oxygen delivery to the chambered dogfish gastric mucosa, experiments were performed to further characterize this tissue under these conditions. Removal of Cl- depressed but did not abolish acid secretion, raised the transepithelial resistance, and caused the potential to become more negative with reference to the mucosal surface. Voltage clamping to -60 mV inhibited secretion significantly; voltage clamping to +60 mV sometimes gave a stimulation. There was no long time-constant transient response to current passage. Under hyperbaric conditions, addition of the normal 350 mM urea content of elasmobranch plasma stimulated secretion. A further increase in partial pressure of oxygen (PO2) above 1.9 atm had no effect on secretion. The current-voltage plot showed two breakpoints, one about -23 mV and a second (not always detectable) at +50 mV; the negative breakpoint was stable as PO2 changed from 0.9 to 1.9 atm. Many of these observations are different from those reported for normabaric tissue and closely resemble those in the isolated frog gastric mucosa.

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