Nondestructive Diagnosis of Drilled Shaft Foundations

1998 ◽  
Vol 1633 (1) ◽  
pp. 120-127 ◽  
Author(s):  
Larry D. Olson ◽  
Marwan F. Aouad ◽  
Dennis A. Sack
Keyword(s):  
Quality Assurance ◽  
The United States ◽  
Ultrasonic Waves ◽  
Drilled Shaft ◽  
Two Dimensional Image ◽  
Existing Structures ◽  
Advantages And Disadvantages ◽  
Ct Data ◽  
Drilled Shaft Foundations ◽  
Concrete Placement

Nondestructive methods based on propagation of sonic and ultrasonic waves are being used increasingly in the United States and internationally for forensic investigations of existing structures and for quality assurance of new construction. Of particular interest is the quality assurance of newly constructed drilled shaft foundations. Many state departments of transportation specify nondestructive testing of drilled shaft foundations, particularly for shafts drilled and placed under wet construction conditions. For quality assurance of drilled shaft foundations of bridges, the crosshole sonic logging (CSL) and sonic echo and impulse response (SE/IR) methods routinely are used. In the CSL method, access tubes are installed in the shaft before concrete placement. SE/IR measurements require that the top of the shaft be accessible after concrete placement. Proper test setups, specifications, and case studies are presented to illustrate the advantages and disadvantages of each of these methods. Also presented are recommendations for repair when a defect is identified in a drilled shaft foundation. The CSL method is more effective for locating defects. CSL measurements are effective for determining anomalies and defects between two access tubes. However, an accurate image of the defect cannot be determined from a CSL test alone. The crosshole tomography (CT) method uses multiple CSL logs with varying receiver locations to produce a two-dimensional image of the defect. The CT method is discussed and a dataset obtained from a drilled shaft foundation is presented. CT data collection and analysis require more time than the CSL method, and the CT method is used only for critical drilled shaft foundations.

scholarly journals Challenges in Bridge Health Monitoring: A Review

Sensors ◽  
2021 ◽  
Vol 21 (13) ◽  
pp. 4336
Author(s):  
Piervincenzo Rizzo ◽  
Alireza Enshaeian
Keyword(s):  
United States ◽  
Health Monitoring ◽  
Highway Bridges ◽  
The United States ◽  
Anomalous Behavior ◽  
Existing Structures ◽  
Bridge Health Monitoring ◽  
Using Data ◽  
The Many ◽  
Major Factors

Bridge health monitoring is increasingly relevant for the maintenance of existing structures or new structures with innovative concepts that require validation of design predictions. In the United States there are more than 600,000 highway bridges. Nearly half of them (46.4%) are rated as fair while about 1 out of 13 (7.6%) is rated in poor condition. As such, the United States is one of those countries in which bridge health monitoring systems are installed in order to complement conventional periodic nondestructive inspections. This paper reviews the challenges associated with bridge health monitoring related to the detection of specific bridge characteristics that may be indicators of anomalous behavior. The methods used to detect loss of stiffness, time-dependent and temperature-dependent deformations, fatigue, corrosion, and scour are discussed. Owing to the extent of the existing scientific literature, this review focuses on systems installed in U.S. bridges over the last 20 years. These are all major factors that contribute to long-term degradation of bridges. Issues related to wireless sensor drifts are discussed as well. The scope of the paper is to help newcomers, practitioners, and researchers at navigating the many methodologies that have been proposed and developed in order to identify damage using data collected from sensors installed in real structures.

‘More Product, Less Process’ (MPLP): An early printed book project

2021 ◽  
pp. 096100062110267
Author(s):  
Karen Attar
Keyword(s):  
18Th Century ◽  
The United States ◽  
Global Changes ◽  
Main Research ◽  
Advantages And Disadvantages ◽  
Main Research Interest ◽  
Printed Books ◽  
Starting Point ◽  
19Th And 20Th Century

This article addresses the challenge to make printed hidden collections known quickly without sacrificing ultimate quality. It takes as its starting point the archival mantra ‘More product, less process’ and explores its application to printed books, mindful of projects in the United States to catalogue 19th- and 20th-century printed books quickly and cheaply with the help of OCLC. A problem is lack of time or managerial inclination ever to return to ‘quick and dirty’ imports. This article is a case study concerning a collection of 18th-century English imprints, the Graveley Parish Library, at Senate House Library, University of London. Faced with the need to provide metadata as quickly as possible for digitisation purposes, Senate House Library decided, in contrast to its normal treatment of early printed books, to download records from the English Short Title Catalogue and amend them only very minimally before releasing them for public view, and to do this work from catalogue cards rather than the books themselves. The article describes the Graveley Parish collection, the project method’s rationale, and the advantages and disadvantages of sourcing the English Short Title Catalogue for metadata. It discusses the drawbacks of retrospective conversion (cataloguing from cards, not books): insufficient detail in some cases to identify the relevant book, and ignorance of the copy-specific elements of books which can constitute the main research interest. The method is compared against cataloguing similar books from photocopies of title pages, and retrospective conversion using English Short Title Catalogue is compared against retrospective conversion of early printed Continental books from cards using Library Hub Discover or OCLC. The control groups show our method’s effectiveness. The project succeeded by producing records fast that fulfilled their immediate purpose and simultaneously would obviously require revisiting. The uniform nature of the collection enabled the saving of time through global changes.

Public-Private Partnership for the Development of Space Sector in the United States and Great Britain

2022 ◽  
pp. 76-87
Author(s):  
V. P. Zavarukhin ◽  
N. D. Frolova ◽  
D. V. Baibulatova
Keyword(s):  
Great Britain ◽  
Space Exploration ◽  
The United States ◽  
Public Private Partnership ◽  
Direct Application ◽  
High Tech ◽  
Private Partnership ◽  
Advantages And Disadvantages ◽  
Space Industry ◽  
Space Activities

The article provides an analysis of modern trends in building public-private partnership (PPP), gives an overview of key studies devoted to this subject in general and PPPs in the field of space activities in particular. The authors analyze the practice of public-private partnerships in the U. S. and Great Britain on the examples of specific mechanisms, their key features, advantages and disadvantages that determine the possibility of their application in different areas of government-business cooperation in the field of space exploration. In order to find possible ways for direct application or adaptation of this experience in Russia for organizing space exploration PPPs the researchers concluded that the level of high-tech production in this country is insufficient and significant administrative barriers for attracting private sector into the space industry are still present.

Part-Time Residency Training

1981 ◽  
Vol 26 (7) ◽  
pp. 484-486 ◽  
Author(s):  
Sandra Fisman ◽  
Lynne Ginsburg
Keyword(s):  
United States ◽  
Career Development ◽  
Residency Training ◽  
Young Women ◽  
Royal College ◽  
The United States ◽  
Women Physicians ◽  
Psychiatry Residents ◽  
Advantages And Disadvantages ◽  
Part Time

The development of part-time training in the United States and Canada is described. The flexibility required for young women physicians who attempt to combine childbearing and career development, together with the increasing number of women entering medicine, underlines the importance of part-time training schedules. A variety of flexible training options have been defined and a set of guidelines has been produced by the Canadian Royal College of Physicians and Surgeons. The experiences of part-time psychiatry residents at Queen's University, Kingston is presented. Thus far this has involved a total of six residents over a four year period, including the authors of this paper. The advantages and disadvantages, viewed from both the resident and system viewpoint, are discussed.

The United States Navy “Standard Day” for Marine Gas Turbines

2017 ◽  
Author(s):  
John Hartranft ◽  
Bruce Thompson ◽  
Dan Groghan
Keyword(s):  
United States ◽  
Gas Turbine ◽  
United States Navy ◽  
Gas Turbines ◽  
The United States ◽  
Industrial Applications ◽  
Jet Engines ◽  
Jet Engine ◽  
Advantages And Disadvantages ◽  
Power Capability

Following the successful development of aircraft jet engines during World War II (WWII), the United States Navy began exploring the advantages of gas turbine engines for ship and boat propulsion. Early development soon focused on aircraft derivative (aero derivative) gas turbines for use in the United States Navy (USN) Fleet rather than engines developed specifically for marine and industrial applications due to poor results from a few of the early marine and industrial developments. Some of the new commercial jet engine powered aircraft that had emerged at the time were the Boeing 707 and the Douglas DC-8. It was from these early aircraft engine successes (both commercial and military) that engine cores such as the JT4-FT4 and others became available for USN ship and boat programs. The task of adapting the jet engine to the marine environment turned out to be a substantial task because USN ships were operated in a completely different environment than that of aircraft which caused different forms of turbine corrosion than that seen in aircraft jet engines. Furthermore, shipboard engines were expected to perform tens of thousands of hours before overhaul compared with a few thousand hours mean time between overhaul usually experienced in aircraft applications. To address the concerns of shipboard applications, standards were created for marine gas turbine shipboard qualification and installation. One of those standards was the development of a USN Standard Day for gas turbines. This paper addresses the topic of a Navy Standard Day as it relates to the introduction of marine gas turbines into the United States Navy Fleet and why it differs from other rating approaches. Lastly, this paper will address examples of issues encountered with early requirements and whether current requirements for the Navy Standard Day should be changed. Concerning other rating approaches, the paper will also address the issue of using an International Organization for Standardization, that is, an International Standard Day. It is important to address an ISO STD DAY because many original equipment manufacturers and commercial operators prefer to rate their aero derivative gas turbines based on an ISO STD DAY with no losses. The argument is that the ISO approach fully utilizes the power capability of the engine. This paper will discuss the advantages and disadvantages of the ISO STD DAY approach and how the USN STD DAY approach has benefitted the USN. For the future, with the advance of engine controllers and electronics, utilizing some of the features of an ISO STD DAY approach may be possible while maintaining the advantages of the USN STD DAY.

scholarly journals THE ROLE OF AMERICAN AND SOVIET WOMEN REPORTERS IN COVERING WORLD WAR II: SPECIFICS OF COVERAGE OF MILITARY ISSUES IN 20th CENTURY JOURNALISM

World Science ◽  
2019 ◽  
Vol 4 (11(51)) ◽  
pp. 37-40
Author(s):  
Tsitsino Bukia ◽  
Nana Parinos
Keyword(s):  
United States ◽  
World War Ii ◽  
20Th Century ◽  
The United States ◽  
World War ◽  
Women Journalists ◽  
Advantages And Disadvantages ◽  
Soviet Space ◽  
Absolutely Closed

A war correspondent has no border, no gender, no religion or race. The only thing a war reporter has - the skills of delivering truth, reflection of the reality in the way it is.The soviet space was absolutely closed to journalism and combat women journalists’ involvement in wars. The field almost consisted of males. Consequently, it seems impossible to analyze and compare the technique of writing of American and SovietWomen. If America freely accepts women for being actively involved in covering war activities, the Soviets obviously refused to do so.The role of a war correspondent is much bigger than one can suppose. Being a war reporter is more than implementing their responsibilities. It goes deeper into the history. A professional combat reporter is a historian facing the history and keeping it for the next generation.The paper considers advantages and disadvantages of being a female combat correspondent in the Soviet space and the United States of America.The role of American and Soviet women reporters in covering WWII.

scholarly journals Passive control of structures for seismic loads

2000 ◽  
Vol 33 (3) ◽  
pp. 209-221 ◽  
Author(s):  
Ian G. Buckle
Keyword(s):  
High Performance ◽  
Passive Control ◽  
Base Isolation ◽  
Mechanical Energy ◽  
Near Field ◽  
The United States ◽  
Industrial Plant ◽  
Passive Systems ◽  
Limit States ◽  
Existing Structures

The control of structures to improve their performance during earthquakes was first proposed more than a century ago. But it has only been in the last 25 years that structures have been successfully designed and built using earthquake protective systems. Today these systems range from simple passive devices to fully active systems. This paper focuses on passive control and reviews recent developments in the state-of-the-art. Passive systems include tuned mass dampers, seismic (base) isolation systems, mechanical energy dissipators, and the like. Major developments in the theory, hardware, design, specification, and installation of these systems have permitted significant applications to buildings, bridges, and industrial plant. Applications are now found in almost all of the seismically active countries of the world, but principally in Italy, Japan, New Zealand and the United States. Noteworthy advantages have been demonstrated when retrofitting existing structures, and designing high-performance structures such as hospitals, emergency response facilities, defense installations, and critical bridges. Field experience in recent earthquakes has confirmed these expectations. There are however limitations to the use of passive systems and these deserve further study and research. They include the uncertainty of response in the near field of an active fault, the non- optimal behavior of passive systems for both small and large earthquakes, and a lack of certainty about the ultimate limit states in unexpectedly large events. As a consequence, in some jurisdictions, code provisions for passive systems are more onerous than for conventional construction, which is a strong disincentive to their use. The limited availability of design guidance in text books, code commentaries, and other design aids are further impediments to the wider use of these systems.

scholarly journals SCREENING IN CARDIOLOGY

2018 ◽  
Vol 7 (4) ◽  
pp. 92-100 ◽  
Author(s):  
I. V. Samorodskaya
Keyword(s):  
Risk Factors ◽  
The United States ◽  
Diagnostic Methods ◽  
Screening Programs ◽  
Advantages And Disadvantages ◽  
Target Populations ◽  
Screening Strategies ◽  
National Programs ◽  
Expensive Process ◽  
Current Guidelines

The organization of screening is a complex and expensive process. Many countries have implemented and continue to implement various health screening programs in the population groups. However, there is a process of refusing to screen certain diseases. In cardiology, some screening strategies are integrated in the national programs aimed at identifying risk factors and preventing chronic non-communicable diseases. None of the countries have established the screening of the entire population for all known cardiovascular diseases (CVD) using all known diagnostic methods. The decision to screen individuals for CVDs / risk factors within the opportunistic screening in the target populations in different countries varies, since it depends on many factors. The article discusses the advantages and disadvantages of screening for CVD, presents current guidelines from professional communities and national services of the United States of America, Great Britain, and Canada.

scholarly journals NAČRTOVAN POROD NA DOMU: PREGLEDNI ČLANEK

2016 ◽  
Vol 85 (3) ◽  
Author(s):  
Tamara Serdinšek ◽  
Iztok Takač
Keyword(s):  
United Kingdom ◽  
The Netherlands ◽  
Home Birth ◽  
The United States ◽  
Home Births ◽  
Mortality And Morbidity ◽  
Advantages And Disadvantages ◽  
Birth Attendants ◽  
Definition Of ◽  
At Home

Background: Home birth is as old as humanity, but still most middle- and high-income countries consider hospitals as the safest birth settings, as complications regarding birth are highly unpredictable. Despite this there are a few countries in which home birth in integrated into official healthcare system (the Netherlands, United Kingdom, Canada etc.). Home births can be divided into unplanned and planned, and the latter can be further categorized by the presence of the birth attendants. This review focuses on planned home births, which are differently represented throughout the world. In the United States 0.6-1.0% of all children are born at home, in the United Kingdom 2-3%, in Canada 1.6% and in the Netherlands 20-30%. For Slovenia, the number of planned home births is unknown; however, in 2010 0.1% of children were born outside medical facilities.Conclusions: The safety of home birth in still under the debate. While research confirms smaller number of obstetric interventions and some complications in mothers who give birth at home, the data regarding the neonatal and perinatal mortality and morbidity is still conflicting. This confirms the need for large multicentric trials in this field. Current home birth guidelines emphasize that women should be well informed regarding the possible advantages and disadvantages of home births. In addition, the emphasis is on definition of selection criteria for home birth, indications for intrapartal transfer to the hospital and appropriate education of birth attendants. 

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