Pipelines in permafrost: geotechnical issues and lessons 12010 R.M. Hardy Address, 63rd Canadian Geotechnical Conference.

2011 ◽  
Vol 48 (9) ◽  
pp. 1412-1431 ◽  
Author(s):  
James M. Oswell
Keyword(s):  
Slope Stability ◽  
Frost Heave ◽  
Terrain Mapping ◽  
Upheaval Buckling ◽  
Technical Developments ◽  
History Of ◽  
Key Issues ◽  
Thaw Settlement ◽  
Design Construction ◽  
Permafrost Regions

Geotechnical input to the design, construction, and operations of pipelines in permafrost may differ significantly from that for pipelines in temperate terrain. The general remoteness and terrain fragility of permafrost regions are key issues that challenge the geotechnical input. Specific geotechnical issues that necessitate input include pipeline routing, slope stability, thaw settlement and frost heave, ditching, buoyancy control, upheaval buckling. and others. This paper examines the history of pipeline development in Canada north of the 60th latitude and highlights some key design issues and some of the technical developments over the past 40 years of design, construction, and operations of pipelines in permafrost regions. Advances have been made in areas such as geothermal modeling, slope stability assessments, terrain mapping technologies, thaw settlement and frost heave prediction, and predicting and monitoring pipeline strain demand.

scholarly journals Stability of the Foundation of Buried Energy Pipeline in Permafrost Region

Geofluids ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-18
Author(s):  
Yan Li ◽  
Huijun Jin ◽  
Zhi Wen ◽  
Xinze Li ◽  
Qi Zhang
Keyword(s):  
Mitigation Strategies ◽  
Slope Instability ◽  
Frost Heave ◽  
Mitigation Measures ◽  
Formation Mechanisms ◽  
Permafrost Region ◽  
Buried Pipelines ◽  
Foundation Soil ◽  
Thaw Settlement ◽  
Permafrost Regions

During operation, a buried pipeline is threatened by a variety of geological hazards, particularly in permafrost regions, where freezing-thawing disasters have a significant influence on the integrity and safety of the buried pipelines. The topographical environmental conditions along the pipeline, as well as the influence of frost heave and thaw settlement on the pipeline’s foundation soil, must be considered in the design and construction stage. Theoretical analysis, numerical modeling, field testing, and mitigation measures on vital energy pipelines in permafrost have been widely documented, but no attempt has been made to review the freezing-thawing disasters, current research methodologies, and mitigation strategies. This article reviews the formation mechanisms and mitigation measures for frost hazards (e.g., differential frost heave, thaw settlement, slope instability, frost mounds, icing, river ice scouring, and pipeline floating) along buried pipelines in permafrost regions and summarizes and prospects the major progress in the research on mechanisms, analysis methods, model test, and field monitoring based on publications of studies of key energy pipelines in permafrost regions. This review will provide scholars with a basic understanding of the challenging freezing-thawing hazards encountered by energy pipelines in permafrost regions, as well as research on the stability and mitigation of pipeline foundation soils plagued by freezing-thawing hazards in permafrost regions under a warming climate and degrading permafrost environment.

Other Biological Approaches to OCD

2012 ◽  
Author(s):  
Nicole C. R. McLaughlin ◽  
Benjamin D. Greenberg
Keyword(s):  
Deep Brain Stimulation ◽  
Brain Stimulation ◽  
Response To Treatment ◽  
History Of ◽  
Key Issues ◽  
Term Management ◽  
Deep Brain

Interest in psychiatric neurosurgery has waxed and waned since the 1930s. This chapter reviews the history of these methods, with a focus on OCD. This review of lesion procedures and deep brain stimulation includes neuropsychological and neuroimaging research in the context of putative neurocircuitry underlying symptoms and response to treatment. The chapter highlights how an abundance of caution is needed, as well as key issues in long-term management of patients so treated.

Permafrost Hazard of MoHe-DaQing Crude Oil Pipeline

2013 ◽  
Vol 734-737 ◽  
pp. 2659-2663
Author(s):  
Yun Bin Ma ◽  
Dong Jie Tan ◽  
Hong Yuan Jing ◽  
Quan Xue ◽  
Cheng Zhi Zhang
Keyword(s):  
Crude Oil ◽  
The Other ◽  
Frost Heave ◽  
Permafrost Soil ◽  
Buried Pipeline ◽  
Soil Frost ◽  
Plastic Deformations ◽  
Oil Pipeline ◽  
Thaw Settlement ◽  
Slope Instabilities

The crude oil pipeline from MoHe to DaQing (hereafter called Mo-Da pipeline) is part of China-Russia oil pipeline. Mo-Da pipeline is the first pipeline that through high latitude cold regions of China. The pipeline is in so complicated geography environment that many kinds of permafrost hazard are easily to happen including frost heave, thaw settlement, slope instabilities, and collapse and so on. The pipeline and the permafrost act and react upon one another. On one hand, soil frost heave and thaw settlement can produce extra stresses on pipe walls, which may result in centralized stresses and plastic deformations under certain conditions, even causes pipeline faults. On the other hand, buried pipeline will disturb ambient environment and then degrade the permafrost soil and finally impact safety of the pipeline. This paper mainly introduces the permafrost hazards of Mo-Da pipeline and demonstrates some methods for monitoring the influence of permafrost.

New and modern history of the Arab world

2019 ◽  
Author(s):  
Rouben Karapetyan
Keyword(s):  
International Relations ◽  
Historical Development ◽  
Arab World ◽  
Arab Countries ◽  
Modern History ◽  
The Past ◽  
Wide Range ◽  
History Of ◽  
Key Issues ◽  
Oriental Studies

The textbook covers the main events and developments in the recent history of the Arab world. The key issues of the past and present of the major Arab countries are examined. The general patterns, main stages and peculiarities of the historical development of these countries are presented. The work is designed for students of the faculties of “Oriental Studies”, “History” and “International Relations”, as well as wide range of readers interested in the history of the Arab world.

“The unity based on memories of former intimacy is an attempt to warm up at a went out fire…” The letters from V.M. Chernov to O.S. Minor and M.I. Klyaver

2021 ◽  
Vol 2021 (04-1) ◽  
pp. 4-39
Author(s):  
Olga Konovalova ◽  
Vera Fedorova ◽  
Anna Dvoretskaya
Keyword(s):  
Civil War ◽  
Social History ◽  
Russian Revolution ◽  
International Institute ◽  
Warm Up ◽  
History Of ◽  
Key Issues ◽  
Shed Light ◽  
Foreign Delegation

In the publication, O.V. Konovalova, V.I. Fedorova, A.P. Dvoretskaya presented letters 1931-1932 of the leader and theoretician of the party of socialists-revolutionaries V.M. Chernov to a prominent figure of the party O.S. Minor and a representative of Harbin socialists-revolutionaries organization M. I. Klyaver regarding the split of the Foreign delegation of the socialists-revolutionaries. They are preserved in the collection of VM. Chernov of the International Archives and Collections at the International Institute of Social History in Amsterdam. The presented letters help to clarify VM. Chernov’s position on the key issues of the history of the SR party during the Russian revolution, Civil War, and emigration of the 1920s, and also shed light on the deep reasons for the split of the ZD AKP.

Peculiar Whiteness

2021 ◽  
Author(s):  
Justin Mellette
Keyword(s):  
Southern Literature ◽  
White Trash ◽  
Poor Whites ◽  
Thomas Dixon ◽  
Close Proximity ◽  
Disparate Treatment ◽  
History Of ◽  
Poor White ◽  
Key Issues ◽  
Fear And Anxiety

Peculiar Whiteness argues for deeper consideration of the complexities surrounding the disparate treatment of poor whites throughout southern literature and attests to how broad such experiences have been. While the history of prejudice against this group is not the same as the legacy of violence perpetrated against people of color in America, individuals regarded as ‘white trash’ have suffered a dehumanizing process in the writings of various white authors. Poor white characters are frequently maligned as grotesque and anxiety-inducing, especially when they are aligned in close proximity to blacks or with other troubling conditions such as physical difference. Thus, as a symbol, much has been asked of poor whites, and various iterations of the label (e.g., ‘white trash,’ tenant farmers, or even people with a little less money than average) have been subject to a broad spectrum of judgment, pity, compassion, fear, and anxiety. Peculiar Whiteness engages key issues in contemporary critical race studies, whiteness studies, and southern studies, both literary and historical. Through discussions of authors including Charles Chesnutt, Thomas Dixon, Erskine Caldwell, William Faulkner, and Flannery O’Connor, the book analyzes how we see how whites in a position of power work to maintain their status, often by finding ways to re-categorize and marginalize people who might not otherwise have seemed to fall under the auspices or boundaries of ‘white trash.’

Stress Analysis of Pipeline Subjected to Differential Frost Heave

2013 ◽  
Author(s):  
Yan Di ◽  
Jian Shuai ◽  
Lingzhen Kong ◽  
Xiayi Zhou
Keyword(s):  
Strain Analysis ◽  
Element Model ◽  
Frozen Soil ◽  
Computational Method ◽  
Frost Heave ◽  
Safe Operation ◽  
Stress Strain ◽  
Segregation Potential ◽  
Differential Frost Heave ◽  
Design Construction

Frost heave must be considered in cases where pipelines are laid in permafrost in order to protect the pipelines from overstress and to maintain the safe operation. In this paper, a finite element model for stress/strain analysis in a pipeline subjected to differential frost heave was presented, in which the amount of frost heave is calculated using a segregation potential model and considering creep effects of the frozen soil. In addition, a computational method for the temperature field around a pipeline was proposed so that the frozen depth and temperature variation gradient could be obtained. Using the procedure proposed in this paper, stress/strain can be calculated according to the temperature on the surface of soil and in a pipeline. The result shows the characteristics of deformation and loading of a pipeline subjected to differential frost heave. In general, the methods and results in this paper can provide a reference for the design, construction and operation of pipelines in permafrost areas.

scholarly journals Women and Gender in 1917

Slavic Review ◽  
2017 ◽  
Vol 76 (3) ◽  
pp. 694-702 ◽  
Author(s):  
Rochelle Goldberg Ruthchild
Keyword(s):  
Political Parties ◽  
Significant Issue ◽  
Women And Gender ◽  
One Dimensional ◽  
History Of ◽  
Key Issues ◽  
And Gender ◽  
Almost All ◽  
The Revolution

This paper argues for greater integration of considerations of women and gender in the history of the 1917 Russian Revolutions. Two key issues have long been discussed by historians: the spontaneity/consciousness paradigm, and the role of class in the revolution. Neither has been adequately analyzed in relation to gender. Women's suffrage has been largely neglected despite the fact that it was a significant issue throughout the year and represented a pioneering advance won by a countrywide coalition of women and men from the working class and intelligentsia, and from almost all political parties. In this centennial year, accounts of the Revolution remain one-dimensional; women remain the other.

Embolization of Non-Ruptured Aneurysms

1999 ◽  
Vol 5 (1_suppl) ◽  
pp. 93-96 ◽  
Author(s):  
C.F. Dowd ◽  
C.C. Phatouros ◽  
A.M. Malek ◽  
T.E. Lempert ◽  
P.M. Meyers ◽  
...  
Keyword(s):  
Intracranial Aneurysms ◽  
Three Dimensional ◽  
Giant Aneurysm ◽  
Epidemiological Data ◽  
Anterior Circulation ◽  
Unruptured Aneurysms ◽  
Aneurysm Neck ◽  
Technical Developments ◽  
History Of ◽  
Anterior Circulation Aneurysms

Options for treatment of intracranial aneurysms have expanded with the advent of the Guglielmi Detachable Cod (GDC) eight years ago. We have reviewed 435 cases of intracranial aneurysms treated at UCSF by endovascular means using the GDC system. Of these, 55% represent anterior circulation aneurysms, and 45% are located in the posterior circulation. Additionally, 55% of the aneurysms presented with subarachnoid hemorrhage (SAH) and 45% were unruptured. Factors which hindered optimal coiling include the following: wide aneurysm neck in relation to the overall aneurysm size, mural thrombus, giant aneurysm, arteries originating from the aneurysm sac, and middle cerebral location. After initial experience was gained, we tended to avoid these aneurysms especially in the non-ruptured group. This may be especially important in light of new epidemiological data suggesting that the natural history of unruptured aneurysms is significantly lower than previously thought. New technical developments which may reduce the risk of treating unruptured aneurysms include the two-dimensional coil, the three-dimensional coil, the balloon-assist technique for wide-necked aneurysms, and combined stent-coil procedures.

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