Nonlinear RPD Analysis of Jack-Up Rigs Including Material Plasticity

2016 ◽  
Author(s):  
Partha Chakrabarti ◽  
Abhijeet Chawan
Keyword(s):  
Lateral Displacement ◽  
3D Analysis ◽  
The Past ◽  
Lateral Offset ◽  
The Many ◽  
Reserve Strength ◽  
Jack Up ◽  
Important Design ◽  
Very High ◽  
Displacement Effects

Rack Phase Difference or RPD may occur during the installation phase of a jack-up rig when it is jacking up at a location. Instances of failure of leg members of a jack-up have been reported in the past. Therefore, this is an important design issue. Among the many causes of high RPD, important ones are when one of the jack-up spudcans becomes eccentrically supported on the bottom or has lateral offset due to preexisting soft spots in the soil during installation. The resulting moment and shear on the leg is carried essentially by the horizontal guide reactions that may induce high stresses leading to failure of a diagonal brace in extreme cases. In a previous OMAE paper written by the authors [1] the importance of a 3D model of the jack-up that uses non-linear analysis methods by including large deformations and rotations was highlighted. In this paper it was also emphasized that the meaning of RPD has to be understood properly in relationship with moment or shear carrying capacity at the spudcan for a given jack-up. The present paper includes material plasticity effects in addition to the other nonlinearities in the 3D analysis to investigate the failure mechanism of a critical brace. Both applied moments due to the vertical load eccentricity at the spudcan and lateral displacement effects of it are considered. The behavior of a trussed leg jack-up depends heavily on the bracing pattern, chord and bay spacing as well as the size of the braces. For a well-designed jack-up the reserve strength beyond the initial exceedance of the allowable limits of member stress following the codes to the actual physical failure is considered to be important. This reserve strength could prevent actual damages to the rig. This paper discusses these aspects using one particular jack-up as example. The particular jack-up has shown very high RPD and reserve strength when a brace fails due to a large spudcan moment being applied or base deflection. The failure of the brace, however, does not indicate that the ultimate strength of the rig has been reached which is expected to be much higher. Although the analysis is for one particular jack-up, it discusses the parameters that in general could make the reserve strength large indicative of good design. These observations and the overall methodology of analysis used here could be beneficial to other rigs.

scholarly journals Evaluating Multi Sector Shocks Effect on the Global Economy

2021 ◽  
Vol 04 (09) ◽  
Author(s):  
Emma Anyika ◽  
Keyword(s):  
Global Economy ◽  
Social Economic ◽  
Great Influence ◽  
Total Risk ◽  
Civil Unrest ◽  
The Past ◽  
Stock Indices ◽  
The World ◽  
The Many ◽  
Very High

The Global economy has experienced various shocks and effects of different impacts. These include war, corruption, civil unrest, politics, piracy, terrorism to name but just a few. These have had a great influence on the global economy such that with the many austerity measures that have been undertaken in the past four years the world at large has not been able to mitigate these influences. Most of the great economies have not recovered yet and if they have it fluctuates. This research generally investigated the sector shock effect on the Global economies by modelling the returns and risks of a sample of major stock indices which were variants since they have been known to capture changes in many economies which may result from social, economic or political happenings. The research then determined a model that could evaluate the effect of various happenings on the averaged Global economy. The multi sector cost of returns was found to be 0.078 or 7.8 % and the multi sector total risk 0.20 or 20.12 %, which is very high 20.12 %. The results then clearly indicated very high risks and low returns during tumultuous times of global happenings.

Motivation behind Agile Software Development over Traditional Development

2015 ◽  
pp. 141-156
Author(s):  
Karun Madan
Keyword(s):  
Software Development ◽  
Failure Rate ◽  
Agile Software Development ◽  
The Other ◽  
Agile Development ◽  
The Past ◽  
Software Development Methodologies ◽  
The Many ◽  
Agile Software ◽  
Very High

Out of the many revolutions in software development methodologies over the past years, no new methodology withstands completely in one way or the other. The failure rate of projects is still very high in spite of so much of revolutionary methodologies come in existence. Unsuccessful projects not only mean the incomplete projects even after deadline or outdated projects but there may be several other scenarios like project did not meet up the real requirements or lack of ability to deal with the changing requirements etc. In this kind of circumstances, projects were never successfully utilized, and another high percentage of projects again required massive rework to be utilizable. Factors like changing requirements and late testing and integration are few of the main causes of this high percentage of failure.This paper reveals how agile development is a way out to the issues linked with traditional software development. Agile development primarily focuses on the rapid delivery of enterprise worth in the form of working software.

Conservatism and Change in Roman Religion

1976 ◽  
Vol 44 ◽  
pp. 1-12 ◽  
Author(s):  
J. A. North
Keyword(s):  
Religious Tradition ◽  
The Self ◽  
Sacred Places ◽  
Roman Religion ◽  
The Real ◽  
The Past ◽  
The Republic ◽  
The Many ◽  
The City ◽  
Very High

The conservatism of the Romans in matters of religion is a generally accepted truth and it is in many ways a very obvious truth. I have no intention of denying it. They set a very high value on their religious tradition; they sought to preserve and reproduce the ceremonies and customs inherited from their ancestors; they thought it wrong and even dangerous to abandon or neglect the many gods, goddesses and sacred places of which the city was full; they had no ideological framework which would have enabled them to think in terms of reforming and improving the national cult, as opposed to reviving and restoring it.I say that this is an obvious truth, because some degree of conservatism in this sense seems to be an inevitable feature of the type of Graeco-Roman paganism of which the Roman State cult is one example. A system in which the emphasis falls primarily on the performance of ritual acts—not on the worshippers' belief, or religious emotions and experiences, or on theology or ethics—such a system inescapably makes it a primary value, though not necessarily the only value, that the known ritual should be successfully repeated. This in turn must imply some implicit respect for the past and for the tradition from which the ritual emerged. For the Romans of any generation, the real validation of their religion lay in the fact that it had worked: that their ancestors had won battles, survived crises, eaten dinners, begotten children and expanded their power by the practice of the self-same rites and ceremonies as they practised themselves. For the Romans of the last generation of the Republic, it was a fact that their ancestors had won more battles and eaten better dinners than anybody else.

On Future Directions in Pathology

1982 ◽  
Vol 40 ◽  
pp. 274-277
Author(s):  
Benjamin F. Trump ◽  
Irene K. Berezesky ◽  
Raymond T. Jones
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Clinical Pathology ◽  
Future Directions ◽  
Diagnostic Pathology ◽  
The Past ◽  
Transmission Electron ◽  
Organ Systems ◽  
The Many

The role of electron microscopy and associated techniques is assured in diagnostic pathology. At the present time, most of the progress has been made on tissues examined by transmission electron microscopy (TEM) and correlated with light microscopy (LM) and by cytochemistry using both plastic and paraffin-embedded materials. As mentioned elsewhere in this symposium, this has revolutionized many fields of pathology including diagnostic, anatomic and clinical pathology. It began with the kidney; however, it has now been extended to most other organ systems and to tumor diagnosis in general. The results of the past few years tend to indicate the future directions and needs of this expanding field. Now, in addition to routine EM, pathologists have access to the many newly developed methods and instruments mentioned below which should aid considerably not only in diagnostic pathology but in investigative pathology as well.

A 200-Year History of the Study of Childhood Language Disorders of Unknown Origin: Changes in Terminology

2020 ◽  
Vol 5 (1) ◽  
pp. 6-11 ◽  
Author(s):  
Laurence B. Leonard
Keyword(s):  
Language Impairment ◽  
Specific Language Impairment ◽  
Scientific Literature ◽  
Language Disorder ◽  
Language Disorders ◽  
Unknown Origin ◽  
Developmental Language Disorder ◽  
The Past ◽  
History Of ◽  
The Many

Purpose The current “specific language impairment” and “developmental language disorder” discussion might lead to important changes in how we refer to children with language disorders of unknown origin. The field has seen other changes in terminology. This article reviews many of these changes. Method A literature review of previous clinical labels was conducted, and possible reasons for the changes in labels were identified. Results References to children with significant yet unexplained deficits in language ability have been part of the scientific literature since, at least, the early 1800s. Terms have changed from those with a neurological emphasis to those that do not imply a cause for the language disorder. Diagnostic criteria have become more explicit but have become, at certain points, too narrow to represent the wider range of children with language disorders of unknown origin. Conclusions The field was not well served by the many changes in terminology that have transpired in the past. A new label at this point must be accompanied by strong efforts to recruit its adoption by clinical speech-language pathologists and the general public.

The Many Pasts of Detective Fiction

2020 ◽  
Vol 1 (2) ◽  
pp. 157-172
Author(s):  
Thomas Leitch
Keyword(s):  
Detective Fiction ◽  
Golden Age ◽  
Public History ◽  
Detective Novel ◽  
Sherlock Holmes ◽  
Detective Story ◽  
The Past ◽  
Wide Range ◽  
Detective Novels ◽  
The Many

Building on Tzvetan Todorov's observation that the detective novel ‘contains not one but two stories: the story of the crime and the story of the investigation’, this essay argues that detective novels display a remarkably wide range of attitudes toward the several pasts they represent: the pasts of the crime, the community, the criminal, the detective, and public history. It traces a series of defining shifts in these attitudes through the evolution of five distinct subgenres of detective fiction: exploits of a Great Detective like Sherlock Holmes, Golden Age whodunits that pose as intellectual puzzles to be solved, hardboiled stories that invoke a distant past that the present both breaks with and echoes, police procedurals that unfold in an indefinitely extended present, and historical mysteries that nostalgically fetishize the past. It concludes with a brief consideration of genre readers’ own ambivalent phenomenological investment in the past, present, and future each detective story projects.

Law as a Field of Tension

2018 ◽  
Author(s):  
Andrea Gamberini
Keyword(s):  
Public Authority ◽  
The Public ◽  
The Past ◽  
Political Cultures ◽  
The Many

As it had been in the communal age, so, in the Visconti-Sforza era, law was the instrument that the public authority relied upon in order to subordinate the many actors present and to subjugate their political cultures. There is, therefore, the attempt to tighten a vice around competing powers—a vice that is at the same time legislative, doctrinal, and judicial. And yet, it is difficult to escape the impression of an effort whose outcomes were somewhat more uncertain than had been the case in the past. The chapter focuses on all these aspects of the deployment of legal and other stratagems to consolidate or to wrest power.

Evidence-based Assessment

2010 ◽  
pp. 76-98
Author(s):  
John Hunsley ◽  
Eric J. Mash
Keyword(s):  
Decision Making ◽  
Clinical Assessment ◽  
Assessment Process ◽  
Evidence Based ◽  
The Past ◽  
Specific Assessment ◽  
The Many ◽  
Selection Of ◽  
Made In

Evidence-based assessment relies on research and theory to inform the selection of constructs to be assessed for a specific assessment purpose, the methods and measures to be used in the assessment, and the manner in which the assessment process unfolds. An evidence-based approach to clinical assessment necessitates the recognition that, even when evidence-based instruments are used, the assessment process is a decision-making task in which hypotheses must be iteratively formulated and tested. In this chapter, we review (a) the progress that has been made in developing an evidence-based approach to clinical assessment in the past decade and (b) the many challenges that lie ahead if clinical assessment is to be truly evidence-based.

CPT-based liquefaction case histories compiled from three earthquakes in Canterbury, New Zealand

2021 ◽  
pp. 875529302199636
Author(s):  
Mertcan Geyin ◽  
Brett W Maurer ◽  
Brendon A Bradley ◽  
Russell A Green ◽  
Sjoerd van Ballegooy
Keyword(s):  
New Zealand ◽  
Case History ◽  
Prediction Models ◽  
Free Field ◽  
Case Histories ◽  
Cone Penetration ◽  
History Data ◽  
The Past ◽  
Surface Manifestation ◽  
The Many

Earthquakes occurring over the past decade in the Canterbury region of New Zealand have resulted in liquefaction case-history data of unprecedented quantity. This provides the profession with a unique opportunity to advance the prediction of liquefaction occurrence and consequences. Toward that end, this article presents a curated dataset containing ∼15,000 cone-penetration-test-based liquefaction case histories compiled from three earthquakes in Canterbury. The compiled, post-processed data are presented in a dense array structure, allowing researchers to easily access and analyze a wealth of information pertinent to free-field liquefaction response (i.e. triggering and surface manifestation). Research opportunities using these data include, but are not limited to, the training or testing of new and existing liquefaction-prediction models. The many methods used to obtain and process the case-history data are detailed herein, as is the structure of the compiled digital file. Finally, recommendations for analyzing the data are outlined, including nuances and limitations that users should carefully consider.

scholarly journals Truck Appointment System for Cooperation between the Transport Companies and the Terminal Operator at Container Terminals

2020 ◽  
Vol 11 (1) ◽  
pp. 168
Author(s):  
Hyeonu Im ◽  
Jiwon Yu ◽  
Chulung Lee
Keyword(s):  
Large Scale ◽  
Container Terminal ◽  
Container Terminals ◽  
The Past ◽  
Cooperation Model ◽  
Appointment System ◽  
New Form ◽  
Truck Appointment System ◽  
Import Container ◽  
Very High

Despite the number of sailings canceled in the past few months, as demand has increased, the utilization of ships has become very high, resulting in sudden peaks of activity at the import container terminals. Ship-to-ship operations and yard activity at the container terminals are at their peak and starting to affect land operations on truck arrivals and departures. In response, a Truck Appointment System (TAS) has been developed to mitigate truck congestion that occurs between the gate and the yard of the container terminal. The vehicle booking system is developed and operated in-house at large-scale container terminals, but efficiency is low due to frequent truck schedule changes by the transport companies (forwarders). In this paper, we propose a new form of TAS in which the transport companies and the terminal operator cooperate. Numerical experiments show that the efficiency of the cooperation model is better by comparing the case where the transport company (forwarder) and the terminal operator make their own decision and the case where they cooperate. The cooperation model shows higher efficiency as there are more competing transport companies (forwarders) and more segmented tasks a truck can reserve.

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