Reality-check and renewed challenges in earthquake engineering

2012 ◽  
Vol 45 (4) ◽  
pp. 137-160 ◽  
Author(s):  
Stefano Pampanin
Keyword(s):  
Seismic Performance ◽  
Earthquake Engineering ◽  
Design Theory ◽  
Damage Control ◽  
Low Cost ◽  
Modern Society ◽  
Cost Effective ◽  
Practical Implementation ◽  
Reality Check ◽  
General Terms

Earthquake Engineering is facing an extraordinarily challenging era, the ultimate target being set at increasingly higher levels by the demanding expectations of our modern society. The renewed challenge is to be able to provide low-cost, thus more widely affordable, high-seismic-performance structures capable of sustaining a design level earthquake with limited or negligible damage, minimum disruption of business (downtime) or, in more general terms, controllable socio-economical losses. The Canterbury earthquakes sequence in 2010-2011 has represented a tough reality check, confirming the current mismatch between societal expectations over the reality of seismic performance of modern buildings. In general, albeit with some unfortunate exceptions, modern multi-storey buildings performed as expected from a technical point of view, in particular when considering the intensity of the shaking (higher than new code design) they were subjected to. As per capacity design principles, plastic hinges formed in discrete regions, allowing the buildings to sway and stand and people to evacuate. Nevertheless, in many cases, these buildings were deemed too expensive to be repaired and were consequently demolished. Targeting life-safety is arguably not enough for our modern society, at least when dealing with new building construction. A paradigm shift towards damage-control design philosophy and technologies is urgently required. This paper and the associated presentation will discuss motivations, issues and, more importantly, cost-effective engineering solutions to design buildings capable of sustaining low-level of damage and thus limited business interruption after a design level earthquake. Focus will be given to the extensive research and developments in jointed ductile connections based upon controlled rocking & dissipating mechanisms for either reinforced concrete and, more recently, laminated timber structures. An overview of recent on-site applications of such systems, featuring some of the latest technical solutions developed in the laboratory and including proposals for the rebuild of Christchurch, will be provided as successful examples of practical implementation of performance-based seismic design theory and technology.

Demonstration of a Practical Method for Seismic Performance Assessment of Structural Systems

2012 ◽  
Vol 28 (2) ◽  
pp. 811-829 ◽  
Author(s):  
T. Y. Yang ◽  
Bozidar Stojadinovic ◽  
Jack Moehle
Keyword(s):  
Seismic Performance ◽  
Earthquake Engineering ◽  
Practical Method ◽  
Performance Comparison ◽  
Practical Implementation ◽  
Structural Systems ◽  
Earthquake Hazards ◽  
Seismic Performance Assessment ◽  
Braced Frame ◽  
Performance Based Earthquake Engineering

Performance-based earthquake engineering aims to describe the seismic performance of a structure using metrics that are of immediate use to both engineers and stakeholders. A rigorous yet practical implementation of performance-based earthquake engineering methodology is used to compare the seismic performance of two steel, concentrically braced structural systems, an inverted-V-braced frame and a suspended zipper-braced frame. The principal difference between these two structural systems is the design approach used to transfer the unbalanced forces when the braces buckle. A probabilistic seismic performance comparison for a three-story office building located in Berkeley, California designed using these two structural systems is presented. The results indicate the suspended zipper-braced frame has lower expected repair cost under different levels of earthquake hazards and is 25% lighter than the corresponding capacity-designed inverted-V-braced frame.

scholarly journals Focusing on reducing the earthquake damage to facade systems

2011 ◽  
Vol 44 (2) ◽  
pp. 108-120 ◽  
Author(s):  
A. Baird ◽  
A. Palermo ◽  
S. Pampanin ◽  
P. Riccio ◽  
A.S. Tasligedik
Keyword(s):  
Earthquake Engineering ◽  
Low Cost ◽  
Modern Society ◽  
Design Guidelines ◽  
Economic Consequences ◽  
Structural Elements ◽  
Structural Components ◽  
Structural Skeleton ◽  
Technical Solutions ◽  
Resistance Structure

Earthquake engineering is facing an extraordinarily challenging era. These challenges are driven by the increasing expectations of modern society to provide low-cost, architecturally appealing structures with high seismic performance. Modern structures need to be able to withstand a design level earthquake with limited or negligible damage such that disruption to business be minimised because of the economic consequences of such downtime. Technological solutions for seismic resisting structural systems are emerging. However, within the goal of developing a seismic-resisting building, not only the structural skeleton of the building but the entire system must be fully protected from damage. This includes the non-structural components of the building such as the claddings, ceilings and contents. Substantial studies are still required to develop technological solutions and design methods capable of achieving such an earthquake resistance structure. This paper presents a review of current technology for facades, including design guidelines for seismic-resistant non-structural components and the steps made towards a performance-based design framework. Alternative conceptual strategies and technical solutions to reduce the damage to non-structural elements will also be introduced.

scholarly journals Low-Cost Solar Heating Reservoir Manufactured by Double-Coating a Water Tank with Polymeric Materials

2020 ◽  
Vol 2 (1) ◽  
pp. 14
Author(s):  
Brino Ruy Negri ◽  
Marco César Prado Soares ◽  
Antonio Carlos Luz Lisboa ◽  
Julio Roberto Bartoli
Keyword(s):  
Solar Energy ◽  
Low Cost ◽  
Polymeric Materials ◽  
Modern Society ◽  
Cost Effective ◽  
Heating System ◽  
Solar Heating ◽  
Water Tank ◽  
Butadiene Rubber ◽  
Domestic Water

One of the main needs of the modern society is the availability of low-cost energy sources, and solar energy arises as an interesting alternative for both the generation of heat and electricity. In this work, a low-cost solar energy reservoir is proposed for domestic water heating. It is comprised of a thermoplastic (polyethylene) water tank thermally insulated by means of two different polymeric coatings: an acrylonitrile butadiene rubber foam, NBR, and a metalized polyester layer. The solar system also contains a flat collector based on a ceiling panel made of poly(vinyl chloride) (PVC) coated with carbon black-filled glaze. The system design is cost effective because all of the parts involved in the solar heating are made from commodity plastic materials. These plastic components present wide commercial availability and are easily handled, so that they can be rapidly assembled to build the entire system. Therefore, the solar heating system is simple, modular, easily scalable, and may be even self-manufactured by the final user. It is an affordable option to the traditional high-cost copper, aluminum and glass solar panels, boilers or tanks used for heat storage.

scholarly journals Chromate-free chemical conversion coatings for aluminum alloys

2019 ◽  
Vol 37 (4) ◽  
pp. 321-342 ◽  
Author(s):  
Markus Becker
Keyword(s):  
Aluminum Alloys ◽  
Low Cost ◽  
Sol Gel ◽  
Cost Effective ◽  
Chemical Conversion ◽  
Practical Implementation ◽  
Conversion Coatings ◽  
Alternative Technologies ◽  
Advantages And Disadvantages ◽  
Near Term

AbstractCorrosion of metallic components represents a major issue in the aeronautical sector, giving rise to safety concerns and significant financial damages. Conversion coatings (CC) based on hexavalent chromium provide exceptional corrosion protection at relatively low cost. However, environmental issues and health concerns raised a growing interest in the development of alternative technologies. These must not only be cost effective and environmentally friendly but also provide corrosion resistance and adhesion performance comparable to Cr6+-based CCs. Simultaneously fulfilling all of these criteria is a difficult challenge, and an industrial application has so far only been achieved by a small number of systems. This review critically summarizes the recent scientific literature and patents for chromate-free CCs on aluminum alloys and tries to assess their potential regarding the highly demanding aerospace requirements. The bath composition and coating characteristics of the trivalent chromium process, rare earth chemical conversion coatings, transition metal oxyanion additives, Zr/Ti-based chemical conversion coatings, sol-gel coatings, and smart coatings providing stimulus-related inhibitor release are discussed. The advantages and disadvantages of the alternative technologies with regard to their practical implementation are debated, as the aeronautics industry is confronted with the necessity to move away from chromates in the near term.

ASSESSMENT OF THE PLATELET COUNT IN THE PREGNANT WOMEN IN IGIMS, PATNA, BIHAR

2020 ◽  
Vol 4 (2) ◽  
Author(s):  
Tanwi Singh ◽  
Anshuman Sinha
Keyword(s):  
Platelet Count ◽  
Pregnant Women ◽  
Screening Test ◽  
Low Cost ◽  
Medical Science ◽  
Cost Effective ◽  
Platelet Indices ◽  
Increased Risk ◽  
Low Platelet Count ◽  
Severity Of The Disease

The major risk associated with low platelet count in pregnancy is the increased risk of bleeding during the childbirth or post that. There is an increased blood supply to the uterus during pregnancy and the surgical procedure requires cutting of major blood vessels. Women with thrombocytopenia are at increased risk of losing excessive blood. The risk is more in case of caesarean delivery as compared to vaginal delivery. Hence based on above findings the present study was planned for Assessment of the Platelet Count in the Pregnant Women in IGIMS, Patna, Bihar. The present study was planned in Department of Pathology, Indira Gandhi Institute of Medical Science, Patna, Bihar, India. The present study was planned from duration of January 2019 to June 2019. In the present study 200 pregnant females samples received for the platelet estimation were enrolled in the present study. Clinically platelet indices can be a useful screening test for early identification of preeclampsia and eclampsia. Also platelet indices can assess the prognosis of this disease in pregnant women and can be used as an effective prognostic marker because it correlates with severity of the disease. Platelet count is a simple, low cost, and rapid routine screening test. Hence the data generated from the present study concludes that platelet count can be used as a simple and cost effective tool to monitor the progression of preeclampsia, thereby preventing complications to develop during the gestational period. Keywords: Platelet Count, Pregnant Women, IGIMS, Patna, Bihar, etc.

Janus – A New Approach to Air Combat Pilot Training

2019 ◽  
Vol 2019 (4) ◽  
pp. 7-22
Author(s):  
Georges Bridel ◽  
Zdobyslaw Goraj ◽  
Lukasz Kiszkowiak ◽  
Jean-Georges Brévot ◽  
Jean-Pierre Devaux ◽  
...  
Keyword(s):  
Low Cost ◽  
Cost Effective ◽  
High Energy ◽  
Training System ◽  
Embedded Sensors ◽  
Pilot Training ◽  
New Approach ◽  
Combat Aircraft ◽  
Air Combat ◽  
The Cost

Abstract Advanced jet training still relies on old concepts and solutions that are no longer efficient when considering the current and forthcoming changes in air combat. The cost of those old solutions to develop and maintain combat pilot skills are important, adding even more constraints to the training limitations. The requirement of having a trainer aircraft able to perform also light combat aircraft operational mission is adding unnecessary complexity and cost without any real operational advantages to air combat mission training. Thanks to emerging technologies, the JANUS project will study the feasibility of a brand-new concept of agile manoeuvrable training aircraft and an integrated training system, able to provide a live, virtual and constructive environment. The JANUS concept is based on a lightweight, low-cost, high energy aircraft associated to a ground based Integrated Training System providing simulated and emulated signals, simulated and real opponents, combined with real-time feedback on pilot’s physiological characteristics: traditionally embedded sensors are replaced with emulated signals, simulated opponents are proposed to the pilot, enabling out of sight engagement. JANUS is also providing new cost effective and more realistic solutions for “Red air aircraft” missions, organised in so-called “Aggressor Squadrons”.

Motivating Compliance: Firm Response to Mandatory Disclosure Policies

2018 ◽  
Vol 32 (2) ◽  
pp. 103-119
Author(s):  
Colleen M. Boland ◽  
Chris E. Hogan ◽  
Marilyn F. Johnson
Keyword(s):  
Conflict Of Interest ◽  
Low Cost ◽  
Cost Effective ◽  
Data Availability ◽  
Policy Adoption ◽  
Future Research ◽  
Regulated Firms ◽  
Firm Response ◽  
Disclosure Rules ◽  
The Impact

SYNOPSIS Mandatory existence disclosure rules require an organization to disclose a policy's existence, but not its content. We examine policy adoption frequencies in the year immediately after the IRS required mandatory existence disclosure by nonprofits of various governance policies. We also examine adoption frequencies in the year of the subsequent change from mandatory existence disclosure to a disclose-and-explain regime that required supplemental disclosures about the content and implementation of conflict of interest policies. Our results suggest that in areas where there is unclear regulatory authority, mandatory existence disclosure is an effective and low cost regulatory device for encouraging the adoption of policies desired by regulators, provided those policies are cost-effective for regulated firms to implement. In addition, we find that disclose-and-explain regulatory regimes provide stronger incentives for policy adoption than do mandatory existence disclosure regimes and also discourage “check the box” behavior. Future research should examine the impact of mandatory existence disclosure rules in the year that the regulation is implemented. Data Availability: Data are available from sources cited in the text.

Azo (Hydrazone) pigments: general principles

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Robert Christie
Keyword(s):  
High Performance ◽  
Metal Salt ◽  
Low Cost ◽  
Cost Effective ◽  
Precipitation Process ◽  
Ambient Temperatures ◽  
Technical Performance ◽  
Chemical Structures ◽  
General Chemical ◽  
Physical Form

Abstract This paper presents an overview of the general chemical principles underlying the structures, synthesis and technical performance of azo pigments, the dominant chemical class of industrial organic pigments in the yellow, orange, and red shade areas, both numerically and in terms of tonnage manufactured. A description of the most significant historical features in this group of pigments is provided, starting from the discovery of the chemistry on which azo colorants are based by Griess in the mid-nineteenth century, through the commercial introduction of the most important classical azo pigments in the early twentieth century, including products known as the Hansa Yellows, β-naphthol reds, including metal salt pigments, and the diarylide yellows and oranges, to the development in the 1950s and 1960s of two classes of azo pigments that exhibit high performance, disazo condensation pigments and benzimidazolone-based azo pigments. A feature that complicates the description of the chemical structures of azo pigments is that they exist in the solid state as the ketohydrazone rather than the hydroxyazo form, in which they have been traditionally been illustrated. Numerous structural studies conducted over the years on an extensive range of azo pigments have demonstrated this feature. In this text, they are referred to throughout as azo (hydrazone) pigments. Since a common synthetic procedure is used in the manufacture of virtually all azo (hydrazone) pigments, this is discussed in some detail, including practical aspects. The procedure brings together two organic components as the fundamental starting materials, a diazo component and a coupling component. An important reason for the dominance of azo (hydrazone) pigments is that they are highly cost-effective. The syntheses generally involve low cost, commodity organic starting materials and are carried out in water as the reaction solvent, which offers obvious economic and environmental advantages. The versatility of the approach means that an immense number of products may be prepared, so that they have been adapted structurally to meet the requirements of many applications. On an industrial scale, the processes are straightforward, making use of simple, multi-purpose chemical plant. Azo pigments may be produced in virtually quantitative yields and the processes are carried out at or below ambient temperatures, thus presenting low energy requirements. Finally, provided that careful control of the reaction conditions is maintained, azo pigments may be prepared directly by an aqueous precipitation process that can optimise physical form, with control of particle size distribution, crystalline structure, and surface character. The applications of azo pigments are outlined, with more detail reserved for subsequent papers on individual products.

scholarly journals Chemical Modification of Combusted Coal Gangue for U(VI) Adsorption: Towards a Waste Control by Waste Strategy

2021 ◽  
Vol 13 (15) ◽  
pp. 8421
Author(s):  
Yuan Gao ◽  
Jiandong Huang ◽  
Meng Li ◽  
Zhongran Dai ◽  
Rongli Jiang ◽  
...  
Keyword(s):  
Structural Analysis ◽  
High Efficiency ◽  
Low Cost ◽  
Chemical Activation ◽  
Cost Effective ◽  
Coal Gangue ◽  
Order Kinetic ◽  
Practical Applications ◽  
Detailed Structural Analysis ◽  
Alkaline Conditions

Uranium mining waste causes serious radiation-related health and environmental problems. This has encouraged efforts toward U(VI) removal with low cost and high efficiency. Typical uranium adsorbents, such as polymers, geopolymers, zeolites, and MOFs, and their associated high costs limit their practical applications. In this regard, this work found that the natural combusted coal gangue (CCG) could be a potential precursor of cheap sorbents to eliminate U(VI). The removal efficiency was modulated by chemical activation under acid and alkaline conditions, obtaining HCG (CCG activated with HCl) and KCG (CCG activated with KOH), respectively. The detailed structural analysis uncovered that those natural mineral substances, including quartz and kaolinite, were the main components in CCG and HCG. One of the key findings was that kalsilite formed in KCG under a mild synthetic condition can conspicuous enhance the affinity towards U(VI). The best equilibrium adsorption capacity with KCG was observed to be 140 mg/g under pH 6 within 120 min, following a pseudo-second-order kinetic model. To understand the improved adsorption performance, an adsorption mechanism was proposed by evaluating the pH of uranyl solutions, adsorbent dosage, as well as contact time. Combining with the structural analysis, this revealed that the uranyl adsorption process was mainly governed by chemisorption. This study gave rise to a utilization approach for CCG to obtain cost-effective adsorbents and paved a novel way towards eliminating uranium by a waste control by waste strategy.

scholarly journals Platforms for Production of Protein-Based Vaccines: From Classical to Next-Generation Strategies

Biomolecules ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1072
Author(s):  
Raquel Cid ◽  
Jorge Bolívar
Keyword(s):  
Infectious Diseases ◽  
Mammalian Cells ◽  
Vaccine Development ◽  
Low Cost ◽  
Cost Effective ◽  
Insect Larvae ◽  
Subunit Vaccines ◽  
Effective Strategies ◽  
Alternative Systems ◽  
Inactivated Vaccines

To date, vaccination has become one of the most effective strategies to control and reduce infectious diseases, preventing millions of deaths worldwide. The earliest vaccines were developed as live-attenuated or inactivated pathogens, and, although they still represent the most extended human vaccine types, they also face some issues, such as the potential to revert to a pathogenic form of live-attenuated formulations or the weaker immune response associated with inactivated vaccines. Advances in genetic engineering have enabled improvements in vaccine design and strategies, such as recombinant subunit vaccines, have emerged, expanding the number of diseases that can be prevented. Moreover, antigen display systems such as VLPs or those designed by nanotechnology have improved the efficacy of subunit vaccines. Platforms for the production of recombinant vaccines have also evolved from the first hosts, Escherichia coli and Saccharomyces cerevisiae, to insect or mammalian cells. Traditional bacterial and yeast systems have been improved by engineering and new systems based on plants or insect larvae have emerged as alternative, low-cost platforms. Vaccine development is still time-consuming and costly, and alternative systems that can offer cost-effective and faster processes are demanding to address infectious diseases that still do not have a treatment and to face possible future pandemics.

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