Self-centering seismic-resistant structures: Historical overview and state-of-the-art

2021 ◽  
pp. 875529302110575
Author(s):  
Chiyun Zhong ◽  
Constantin Christopoulos

This state-of-the-art review provides an overview of the evolution of self-centering structures from early historical structures that inherently exhibited a recentering response to modern systems engineered for enhanced seismic resilience. From the early research investigations that were conducted since the 1960s, to the sharp increase of interest in this topic over the last two decades, self-centering seismic-resistant structures that can mitigate both damage and residual drifts following major earthquakes have seen significant advances. These systems achieve the intended self-centering response by either allowing for the rocking of primary structural elements in a controlled manner, commonly coupled with mechanical restraints and energy dissipation devices, or by including self-centering devices as main structural or supplemental structural members. To better explain the concepts and the underlying mechanics governing their seismic response, detailed schematic illustrations were developed in this article, highlighting the fundamentals behind each of these systems. This article covers a historical overview, presents the state of the research and of the art, discusses general design challenges and practical considerations, and concludes with future research needs to advance the development and broader application of self-centering systems in real structures.

1981 ◽  
pp. 77
Author(s):  
Vitelmo Bertero

This is a paper that summarizes the state of the practice and state of the art in the prediction of seismic behavior of cylindrical liquid storage tanks. It can be divided into five parts. In the first part the seismic performance of these types of tanks during recent   earthquakes is brielfly reviewed. From this review it becomes evident that a large percentage of these tanks have failed or suffered severe damages. The different types of failure are classified into several categories. The second part of the paper discusses the desing of some of the thank that suffered damages andthe state of the practice is summarized by reviewing present seismic code desing provisions. Thirdly, the soundness of these code provisions is analyzed in view of the state of thank.  Results obtained in recent theoretical and experimental investigations of such behavior are summarized and implications regarding needed improvement in seismic desing are assessed. Results from analyses of an existing  thank using different methods are presented and compared. An improved procedure for the practical seismic resistant desing of these thanks is outlined in the fourth part of the paper. A series of practical desing rules which provide extra margins of safety are offered and the extra cost required is discussed. Finally, recommendations for future research to improve the desing and construction of this type of liquid storage thanks are formuated.


Author(s):  
Muhammad Yousaf ◽  
Petr Bris

A systematic literature review (SLR) from 1991 to 2019 is carried out about EFQM (European Foundation for Quality Management) excellence model in this paper. The aim of the paper is to present state of the art in quantitative research on the EFQM excellence model that will guide future research lines in this field. The articles were searched with the help of six strings and these six strings were executed in three popular databases i.e. Scopus, Web of Science, and Science Direct. Around 584 peer-reviewed articles examined, which are directly linked with the subject of quantitative research on the EFQM excellence model. About 108 papers were chosen finally, then the purpose, data collection, conclusion, contributions, and type of quantitative of the selected papers are discussed and analyzed briefly in this study. Thus, this study identifies the focus areas of the researchers and knowledge gaps in empirical quantitative literature on the EFQM excellence model. This article also presents the lines of future research.


Author(s):  
Jacques Thomassen ◽  
Carolien van Ham

This chapter presents the research questions and outline of the book, providing a brief review of the state of the art of legitimacy research in established democracies, and discusses the recurring theme of crisis throughout this literature since the 1960s. It includes a discussion of the conceptualization and measurement of legitimacy, seeking to relate legitimacy to political support, and reflecting on how to evaluate empirical indicators: what symptoms indicate crisis? This chapter further explains the structure of the three main parts of the book. Part I evaluates in a systematic fashion the empirical evidence for legitimacy decline in established democracies; Part II reappraises the validity of theories of legitimacy decline; and Part II investigates what (new) explanations can account for differences in legitimacy between established democracies. The chapter concludes with a short description of the chapters included in the volume.


2021 ◽  
Vol 54 (7) ◽  
pp. 1-39
Author(s):  
Ankur Lohachab ◽  
Saurabh Garg ◽  
Byeong Kang ◽  
Muhammad Bilal Amin ◽  
Junmin Lee ◽  
...  

Unprecedented attention towards blockchain technology is serving as a game-changer in fostering the development of blockchain-enabled distinctive frameworks. However, fragmentation unleashed by its underlying concepts hinders different stakeholders from effectively utilizing blockchain-supported services, resulting in the obstruction of its wide-scale adoption. To explore synergies among the isolated frameworks requires comprehensively studying inter-blockchain communication approaches. These approaches broadly come under the umbrella of Blockchain Interoperability (BI) notion, as it can facilitate a novel paradigm of an integrated blockchain ecosystem that connects state-of-the-art disparate blockchains. Currently, there is a lack of studies that comprehensively review BI, which works as a stumbling block in its development. Therefore, this article aims to articulate potential of BI by reviewing it from diverse perspectives. Beginning with a glance of blockchain architecture fundamentals, this article discusses its associated platforms, taxonomy, and consensus mechanisms. Subsequently, it argues about BI’s requirement by exemplifying its potential opportunities and application areas. Concerning BI, an architecture seems to be a missing link. Hence, this article introduces a layered architecture for the effective development of protocols and methods for interoperable blockchains. Furthermore, this article proposes an in-depth BI research taxonomy and provides an insight into the state-of-the-art projects. Finally, it determines possible open challenges and future research in the domain.


Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4171
Author(s):  
Rabia Ikram ◽  
Badrul Mohamed Jan ◽  
Akhmal Sidek ◽  
George Kenanakis

An important aspect of hydrocarbon drilling is the usage of drilling fluids, which remove drill cuttings and stabilize the wellbore to provide better filtration. To stabilize these properties, several additives are used in drilling fluids that provide satisfactory rheological and filtration properties. However, commonly used additives are environmentally hazardous; when drilling fluids are disposed after drilling operations, they are discarded with the drill cuttings and additives into water sources and causes unwanted pollution. Therefore, these additives should be substituted with additives that are environmental friendly and provide superior performance. In this regard, biodegradable additives are required for future research. This review investigates the role of various bio-wastes as potential additives to be used in water-based drilling fluids. Furthermore, utilization of these waste-derived nanomaterials is summarized for rheology and lubricity tests. Finally, sufficient rheological and filtration examinations were carried out on water-based drilling fluids to evaluate the effect of wastes as additives on the performance of drilling fluids.


2019 ◽  
Vol 64 (2) ◽  
pp. 230-268
Author(s):  
Dirk Siepmann

Abstract Combining traditional methods with state-of-the-art corpus analysis, this article discusses problems associated with the translation of general academic lexis from German into English. In particular, it offers a more nuanced view on the often-made claim that there are ‘major differences’ between the two languages, many of which are said to stem from the spatial metaphorics underlying general academic German. Section 1 deals with problems that arise at the level of words and their lexico-syntactic environment, paying particular attention to spatial metaphor. Moving on to level of the paragraph, Section 2 continues the theme of spatial metaphor, showing how even quasi-terminological equivalents such as Struktur and structure exhibit subtle differences in use and may occasionally require re-metaphorization under the influence of the wider context. Section 3 provides a summary of the argument and suggests avenues for future research.


Electrochem ◽  
2021 ◽  
Vol 2 (1) ◽  
pp. 149-184
Author(s):  
Francisco T. T. Cavalcante ◽  
Italo R. R. de A. Falcão ◽  
José E. da S. Souza ◽  
Thales G. Rocha ◽  
Isamayra G. de Sousa ◽  
...  

Among the many biological entities employed in the development of biosensors, enzymes have attracted the most attention. Nanotechnology has been fostering excellent prospects in the development of enzymatic biosensors, since enzyme immobilization onto conductive nanostructures can improve characteristics that are crucial in biosensor transduction, such as surface-to-volume ratio, signal response, selectivity, sensitivity, conductivity, and biocatalytic activity, among others. These and other advantages of nanomaterial-based enzymatic biosensors are discussed in this work via the compilation of several reports on their applications in different industrial segments. To provide detailed insights into the state of the art of this technology, all the relevant concepts around the topic are discussed, including the properties of enzymes, the mechanisms involved in their immobilization, and the application of different enzyme-derived biosensors and nanomaterials. Finally, there is a discussion around the pressing challenges in this technology, which will be useful for guiding the development of future research in the area.


1987 ◽  
Vol 6 (1) ◽  
pp. 26-56 ◽  
Author(s):  
Robert C. Klesges ◽  
Jeffrey Cigrang ◽  
Russell E. Glasgow

Sign in / Sign up

Export Citation Format

Share Document