Handbook of Materials Failure Analysis with Case Studies from the Aerospace and Automotive Industries

Handbook of Materials Failure Analysis with Case Studies from the Aerospace and Automotive Industries
Author: Abdel Salam Hamdy Makhlouf,Mahmood Aliofkhazraei
Publsiher: Butterworth-Heinemann
Total Pages: 524
Release: 2015-09-01
ISBN 10: 0128011777
ISBN 13: 9780128011775
Language: EN, FR, DE, ES & NL

Handbook of Materials Failure Analysis with Case Studies from the Aerospace and Automotive Industries Book Review:

Handbook of Materials Failure Analysis: With Case Studies from the Aerospace and Automotive Industries provides a thorough understanding of the reasons materials fail in certain situations, covering important scenarios, including material defects, mechanical failure as a result of improper design, corrosion, surface fracture, and other environmental causes. The book begins with a general overview of materials failure analysis and its importance, and then logically proceeds from a discussion of the failure analysis process, types of failure analysis, and specific tools and techniques, to chapters on analysis of materials failure from various causes. Later chapters feature a selection of newer examples of failure analysis cases in such strategic industrial sectors as aerospace, oil & gas, and chemicals. Covers the most common types of materials failure, analysis, and possible solutions Provides the most up-to-date and balanced coverage of failure analysis, combining foundational knowledge, current research on the latest developments, and innovations in the field Ideal accompaniment for those interested in materials forensic investigation, failure of materials, static failure analysis, dynamic failure analysis, fatigue life prediction, rotorcraft, failure prediction, fatigue crack propagation, bevel pinion failure, gasketless flange, thermal barrier coatings Presents compelling new case studies from key industries to demonstrate concepts Highlights the role of site conditions, operating conditions at the time of failure, history of equipment and its operation, corrosion product sampling, metallurgical and electrochemical factors, and morphology of failure

Handbook of Materials Failure Analysis with Case Studies from the Oil and Gas Industry

Handbook of Materials Failure Analysis with Case Studies from the Oil and Gas Industry
Author: Abdel Salam Hamdy Makhlouf,Mahmood Aliofkhazraei
Publsiher: Butterworth-Heinemann
Total Pages: 448
Release: 2015-09-01
ISBN 10: 0081001266
ISBN 13: 9780081001264
Language: EN, FR, DE, ES & NL

Handbook of Materials Failure Analysis with Case Studies from the Oil and Gas Industry Book Review:

Handbook of Materials Failure Analysis: With Case Studies from the Oil and Gas Industry provides an updated understanding on why materials fail in specific situations, a vital element in developing and engineering new alternatives. This handbook covers analysis of materials failure in the oil and gas industry, where a single failed pipe can result in devastating consequences for people, wildlife, the environment, and the economy of a region. The book combines introductory sections on failure analysis with numerous real world case studies of pipelines and other types of materials failure in the oil and gas industry, including joint failure, leakage in crude oil storage tanks, failure of glass fibre reinforced epoxy pipes, and failure of stainless steel components in offshore platforms, amongst others. Introduces readers to modern analytical techniques in materials failure analysis Combines foundational knowledge with current research on the latest developments and innovations in the field Includes numerous compelling case studies of materials failure in oil and gas pipelines and drilling platforms

Handbook of Materials Failure Analysis

Handbook of Materials Failure Analysis
Author: Abdel Salam Hamdy Makhlouf,Mahmood Aliofkhazraei
Publsiher: Butterworth-Heinemann
Total Pages: 372
Release: 2018-04-27
ISBN 10: 0081019297
ISBN 13: 9780081019290
Language: EN, FR, DE, ES & NL

Handbook of Materials Failure Analysis Book Review:

Handbook of Materials Failure Analysis: With Case Studies from the Construction Industry provides a thorough understanding of the reasons materials fail in certain situations, covering important scenarios including material defects, mechanical failure due to various causes, and improper material selection and/or corrosive environment. The book begins with a general overview of materials failure analysis and its importance, and then logically proceeds from a discussion of the failure analysis process, types of failure analysis, and specific tools and techniques, to chapters on analysis of materials failure from various causes. Failure can occur for several reasons, including: materials defects-related failure, materials design-related failure, or corrosion-related failures. The suitability of the materials to work in a definite environment is an important issue. The results of these failures can be catastrophic in the worst case scenarios, causing loss of life. This important reference covers the most common types of materials failure, and provides possible solutions. Provides the most up-to-date and balanced coverage of failure analysis, combining foundational knowledge and current research on the latest developments and innovations in the field Offers an ideal accompaniment for those interested in materials forensic investigation, failure of materials, static failure analysis, dynamic failure analysis, and fatigue life prediction Presents compelling new case studies from key industries to demonstrate concepts and to assist users in avoiding costly errors that could result in catastrophic events

Handbook of Materials Failure Analysis with Case Studies from the Chemicals Concrete and Power Industries

Handbook of Materials Failure Analysis with Case Studies from the Chemicals  Concrete and Power Industries
Author: Abdel Salam Hamdy Makhlouf,Mahmood Aliofkhazraei
Publsiher: Butterworth-Heinemann
Total Pages: 470
Release: 2015-09-07
ISBN 10: 0081001258
ISBN 13: 9780081001257
Language: EN, FR, DE, ES & NL

Handbook of Materials Failure Analysis with Case Studies from the Chemicals Concrete and Power Industries Book Review:

Handbook of Materials Failure Analysis: With Case Studies from the Chemicals, Concrete and Power Industries provides an in-depth examination of materials failure in specific situations, a vital component in both developing and engineering new solutions. This handbook covers analysis of materials failure in the chemical, power, and structures arenas, where the failure of a single component can result in devastating consequences and costs. Material defects, mechanical failure as a result of improper design, corrosion, surface fracture, and other failure mechanisms are described in the context of real world case studies involving steam generators, boiler tubes, gas turbine blades, welded structures, chemical conversion reactors and more. This book is an indispensable reference for engineers and scientists studying the mechanisms of failure in these fields. Introduces readers to modern analytical techniques in materials failure analysis Combines foundational knowledge with current research on the latest developments and innovations in the field Includes many compelling case studies of materials failure in chemical processing plants, concrete structures, and power generation systems

Handbook of Materials Failure Analysis

Handbook of Materials Failure Analysis
Author: Abdel Salam Hamdy Makhlouf,Mahmood Aliofkhazraei
Publsiher: Butterworth-Heinemann
Total Pages: 384
Release: 2019-10-22
ISBN 10: 0128113960
ISBN 13: 9780128113967
Language: EN, FR, DE, ES & NL

Handbook of Materials Failure Analysis Book Review:

Handbook of Materials Failure Analysis: With Case Studies from the Electronics Industries examines the reasons materials fail in certain situations, including material defects and mechanical failure as a result of various causes. The book begins with a general overview of materials failure analysis and its importance. It then proceeds to discussions on the types of failure analysis, specific tools and techniques, and an analysis of materials failure from various causes. As failure can occur for several reasons, including materials defects-related failure, materials design-related failure, or corrosion-related failures, the topics covered in this comprehensive source are an important tool for practitioners. Provides the most up-to-date and balanced coverage of failure analysis, combining foundational knowledge and current research on the latest developments and innovations in the field Offers an ideal accompaniment for those interested in materials forensic investigation, failure of materials, static failure analysis, dynamic failure analysis, and fatigue life prediction Presents compelling new case studies from key industries to demonstrate concepts

Handbook of Case Histories in Failure Analysis Volume 2

Handbook of Case Histories in Failure Analysis  Volume 2
Author: Khlefa Alarbe Esaklul
Publsiher: ASM International
Total Pages: 583
Release: 1992
ISBN 10: 9780871704955
ISBN 13: 0871704951
Language: EN, FR, DE, ES & NL

Handbook of Case Histories in Failure Analysis Volume 2 Book Review:

Presents more than 120 expert failure analysis case histories from industries including automotive, aerospace, utilities, oil and gas, petrochemical, biomedical, ground transportation, off-highway vehicles, and more. Volume 2 builds on the tremendous acceptance of Volume 1 by the failure analysis community. The two volumes can also be purchased as a set for a special discounted price. Learn how others have investigated and solved failures in various industries involving a wide range of failure modes, materials, and analysis techniques.

Electronic Failure Analysis Handbook

Electronic Failure Analysis Handbook
Author: Perry L. Martin
Publsiher: McGraw Hill Professional
Total Pages: 520
Release: 1999
ISBN 10: 9780070410442
ISBN 13: 0070410445
Language: EN, FR, DE, ES & NL

Electronic Failure Analysis Handbook Book Review:

Offering top-to-bottom coverage of this rapidly developing field; this book encompasses breakthrough techniques and technologies for both components and systems reliability testing; performance evaluation; and liability avoidance. --

Handbook of Environmental Degradation of Materials

Handbook of Environmental Degradation of Materials
Author: Myer Kutz
Publsiher: William Andrew
Total Pages: 936
Release: 2012-10-08
ISBN 10: 1437734553
ISBN 13: 9781437734553
Language: EN, FR, DE, ES & NL

Handbook of Environmental Degradation of Materials Book Review:

Nothing stays the same for ever. The environmental degradation and corrosion of materials is inevitable and affects most aspects of life. In industrial settings, this inescapable fact has very significant financial, safety and environmental implications. The Handbook of Environmental Degradation of Materials explains how to measure, analyse, and control environmental degradation for a wide range of industrial materials including metals, polymers, ceramics, concrete, wood and textiles exposed to environmental factors such as weather, seawater, and fire. Divided into sections which deal with analysis, types of degradation, protection and surface engineering respectively, the reader is introduced to the wide variety of environmental effects and what can be done to control them. The expert contributors to this book provide a wealth of insider knowledge and engineering knowhow, complementing their explanations and advice with Case Studies from areas such as pipelines, tankers, packaging and chemical processing equipment ensures that the reader understands the practical measures that can be put in place to save money, lives and the environment. The Handbook's broad scope introduces the reader to the effects of environmental degradation on a wide range of materials, including metals, plastics, concrete,wood and textiles For each type of material, the book describes the kind of degradation that effects it and how best to protect it Case Studies show how organizations from small consulting firms to corporate giants design and manufacture products that are more resistant to environmental effects

Metal Fatigue Analysis Handbook

Metal Fatigue Analysis Handbook
Author: Yung-Li Lee,Mark E. Barkey,Hong-Tae Kang
Publsiher: Elsevier
Total Pages: 580
Release: 2011
ISBN 10: 0123852048
ISBN 13: 9780123852045
Language: EN, FR, DE, ES & NL

Metal Fatigue Analysis Handbook Book Review:

Understand why fatigue happens and how to model, simulate, design and test for it with this practical, industry-focused reference Written to bridge the technology gap between academia and industry, the Metal Fatigue Analysis Handbook presents state-of-the-art fatigue theories and technologies alongside more commonly used practices, with working examples included to provide an informative, practical, complete toolkit of fatigue analysis. Prepared by an expert team with extensive industrial, research and professorial experience, the book will help you to understand: Critical factors that cause and affect fatigue in the materials and structures relating to your work Load and stress analysis in addition to fatigue damage-the latter being the sole focus of many books on the topic How to design with fatigue in mind to meet durability requirements How to model, simulate and test with different materials in different fatigue scenarios The importance and limitations of different models for cost effective and efficient testing Whilst the book focuses on theories commonly used in the automotive industry, it is also an ideal resource for engineers and analysts in other disciplines such as aerospace engineering, civil engineering, offshore engineering, and industrial engineering. The only book on the market to address state-of-the-art technologies in load, stress and fatigue damage analyses and their application to engineering design for durability Intended to bridge the technology gap between academia and industry-written by an expert team with extensive industrial, research and professorial experience in fatigue analysis and testing An advanced mechanical engineering design handbook focused on the needs of professional engineers within automotive, aerospace and related industrial disciplines

Aircraft Materials and Analysis

Aircraft Materials and Analysis
Author: Tariq Siddiqui
Publsiher: McGraw Hill Professional
Total Pages: 288
Release: 2014-12-06
ISBN 10: 0071831142
ISBN 13: 9780071831147
Language: EN, FR, DE, ES & NL

Aircraft Materials and Analysis Book Review:

Complete coverage of aircraft design, manufacturing, and maintenance Aircraft Materials and Analysis addresses aircraft design, mechanical and structural factors in aviation, flight loads, structural integrity, stresses, properties of materials, compression, bending, and aircraft fatigue. Detailed analysis of the failure process is provided. This authoritative guide examines materials used in aircraft construction such as aluminum, steel, glass, composite, rubber, and carbon fiber. Maintenance procedures for corrosion and aging aircraft are discussed and methods of inspection such as nondestructive testing and nondestructive inspection are described. Accident investigation case studies review aircraft design, material behavior, NTSB findings, safety, stress factors, and human factor involvement. End-of-chapter questions reinforce the topics covered in this practical resource. Aircraft Materials and Analysis covers: The aircraft--standards for design, structural integrity, and system safety Aircraft materials Loads on the aircraft Stress analysis Torsion, compression, and bending loads Aircraft riveted joints and pressure vessels Heat treatments of metals Aircraft fatigue/aircraft material fatigue Aircraft corrosion Dynamic stress, temperature stress, and experimental methods Composites Nondestructive Testing (NDT) Aviation maintenance management Case studies and human factors

Metallurgical Failure Analysis

Metallurgical Failure Analysis
Author: Kannadi Palankeezhe Balan
Publsiher: Elsevier
Total Pages: 294
Release: 2018-01-03
ISBN 10: 0128143371
ISBN 13: 9780128143377
Language: EN, FR, DE, ES & NL

Metallurgical Failure Analysis Book Review:

Metallurgical Failure Analysis: Techniques and Case Studies explores how components fail and what measures should be taken to avoid future failures. The book introduces the subject of failure analysis; covers the fundamentals and methodology of failure analysis, including fracture and fractography of metals and alloys and the tools and techniques used in a failure investigation; examines 37 case studies on high performance engineering components; features experimental results comprised of visual-, fractographic-, or metallographic- examination, hardness measurements and chemical analysis; includes illustrations and evidence obtained through test results to enhance understanding; and suggests suitable remedial measures when possible. The various case studies are classified according to the major causes of failures. The case studies pertain to: Improper Material Selection, Manufacturing Defects, Casting Defects, Overload, Fatigue, Corrosion Induced Failures, Hydrogen Embrittlement and Stress Corrosion Cracking, Wear and Elevated Temperature Failures. The book contains information gathered over three decades of the author’s experience handling a variety of failure cases and will go a long way toward inspiring practicing failure analysts. The book is designed for scientists, metallurgists, engineers, quality control inspectors, professors and students alike. Explores the fundamentals and methodology of failure analysis Examines the major causes of component failures Teaches a systematic approach to investigation to determine the cause of a failure Features 37 case studies on high performance engineering components

Materials and Process Selection for Engineering Design

Materials and Process Selection for Engineering Design
Author: Mahmoud M. Farag
Publsiher: CRC Press
Total Pages: 538
Release: 2013-11-19
ISBN 10: 1466564105
ISBN 13: 9781466564107
Language: EN, FR, DE, ES & NL

Materials and Process Selection for Engineering Design Book Review:

Introducing a new engineering product or changing an existing model involves making designs, reaching economic decisions, selecting materials, choosing manufacturing processes, and assessing its environmental impact. These activities are interdependent and should not be performed in isolation from each other. This is because the materials and proce

Failure Analysis Case Studies II

Failure Analysis Case Studies II
Author: D.R.H. Jones
Publsiher: Elsevier
Total Pages: 456
Release: 2013-10-22
ISBN 10: 0080545556
ISBN 13: 9780080545554
Language: EN, FR, DE, ES & NL

Failure Analysis Case Studies II Book Review:

The first book of Failure Analysis Case Studies selected from volumes 1, 2 and 3 of the journal Engineering Failure Analysis was published by Elsevier Science in September 1998. The book has proved to be a sought-after and widely used source of reference material to help people avoid or analyse engineering failures, design and manufacture for greater safety and economy, and assess operating, maintenance and fitness-for-purpose procedures. In the last three years, Engineering Failure Analysis has continued to build on its early success as an essential medium for the publication of failure analysis cases studies and papers on the structure, properties and behaviour of engineering materials as applied to real problems in structures, components and design. Failure Analysis Case Studies II comprises 40 case studies describing the analysis of real engineering failures which have been selected from volumes 4, 5 and 6 of Engineering Failure Analysis. The case studies have been arranged in sections according to the specific type of failure mechanism involved. The failure mechanisms covered are overload, creep, brittle fracture, fatigue, environmental attack, environmentally assisted cracking and bearing failures. The book constitutes a reference set of real failure investigations which should be useful to professionals and students in most branches of engineering.

Introducing New Materials in the Automotive Industry

Introducing New Materials in the Automotive Industry
Author: Fredrik Henriksson
Publsiher: Linköping University Electronic Press
Total Pages: 135
Release: 2017-11-15
ISBN 10: 9176853977
ISBN 13: 9789176853979
Language: EN, FR, DE, ES & NL

Introducing New Materials in the Automotive Industry Book Review:

Passenger vehicles are central to Western society, and contribute to a signi?cant part of our greenhouse gas emissions. In order to reduce emissions, the automotive industry as a whole is working to reduce mass in passenger vehicles in order to reduce energy consumption. One way to reduce mass is to introduce lightweight materials in the body of the vehicle. This research aims to explore the relationship between product and production system when introducing new materials. Besides a theoretical review and an industry-centered technological mapping, four case studies have been conducted during the course of this licentiate thesis. Two case studies were conducted with engineering design students working as development teams, one case study with the author as the developer and ?nally one case study in an industrial environment at a product owning company with in-house production. The goal of the case studies has been to increase the collective knowledge of how product development decisions affect production development decisions, and vice versa, when developing passenger vehicles in new materials. In the following analysis of case study outcomes, a number of factors important for introducing new materials are discussed. The relationship between product and production is investigated, both in terms of how the production system affects the product and how the product affects the production system. The outcome from this analysis is a mapping of important factors for automotive industry companies to understand and identify when looking at introducing new materials in existing production systems. Finally, a suggestion for future research efforts is presented.

Failure Analysis of Heat Treated Steel Components

Failure Analysis of Heat Treated Steel Components
Author: Lauralice de Campos Franceschini Canale,George E. Totten,Rafael A. Mesquita
Publsiher: ASM International
Total Pages: 640
Release: 2008
ISBN 10: 1615030980
ISBN 13: 9781615030989
Language: EN, FR, DE, ES & NL

Failure Analysis of Heat Treated Steel Components Book Review:

Encyclopedia and Handbook of Materials Parts and Finishes

Encyclopedia and Handbook of Materials  Parts and Finishes
Author: Mel Schwartz
Publsiher: CRC Press
Total Pages: 1070
Release: 2016-07-06
ISBN 10: 1138032069
ISBN 13: 9781138032064
Language: EN, FR, DE, ES & NL

Encyclopedia and Handbook of Materials Parts and Finishes Book Review:

A great deal of progress has been made in the development of materials, their application to structures, and their adaptation to a variety of systems and integrated across a wide range of industrial applications. This encyclopedia serves the rapidly expanding demand for information on technological developments. In addition to providing information

Sheet Metal Forming Optimization

Sheet Metal Forming Optimization
Author: Ganesh M. Kakandikar,Vilas M. Nandedkar
Publsiher: CRC Press
Total Pages: 234
Release: 2017-10-16
ISBN 10: 1351652184
ISBN 13: 9781351652186
Language: EN, FR, DE, ES & NL

Sheet Metal Forming Optimization Book Review:

Automotive and aerospace components, utensils, and many other products are manufactured by a forming/drawing process on press machines of very thin sheet metal, 0.8 to 1.2 mm. It is imperative to study the effect of all involved parameters on output of this type of manufacturing process. This book offers the readers with application and suitability of various evolutionary, swarm, and bio-inspired optimization algorithms for sheet metal forming processes. Book initiates by presenting basics of metal forming, formability followed by discussion of process parameters in detail, prominent modes of failure, basics of optimization and various bioinspired approaches followed by optimization studies on various industrial components applying bioinspired optimization algorithms. Key Features: • Focus on description of basic investigation of metal forming, as well as evolutionary optimization • Presentation of innovative optimization methodologies to close the gap between those formulations and industrial problems, aimed at industrial professionals • Includes mathematical modeling of drawing/forming process • Discusses key performance parameters, such as Thinning, Fracture, and Wrinkling • Includes both numerical and experimental analysis

Gower Handbook of Programme Management

Gower Handbook of Programme Management
Author: D Lock,Reinhard Wagner
Publsiher: Routledge
Total Pages: 602
Release: 2020-07-26
ISBN 10: 1000152073
ISBN 13: 9781000152074
Language: EN, FR, DE, ES & NL

Gower Handbook of Programme Management Book Review:

In the ten years since this Gower Handbook was first published, Programme Management has been transformed to become the vehicle of choice for realising the objectives of large scale, complicated, business, government and social investment. The Second Edition of this Gower Handbook is a completely new text; designed as a definitive guide to the current state of Programme Management. To that end the text offers foundation theory and knowledge around key issues such as, managing programme contracts, people and know-how, complexity and uncertainty, benefits and success measures, as well as every stage of the programme life cycle. The main central section of the book provides theory, tools, advice and examples of practical application from an industry context and covers sectors including construction, energy, aerospace and defence, IT, automotive and the public sector. The Handbook also includes a section with chapters on assessing and improving programme competences and developing maturity. Discrete chapters relate programme management to the international baselines and standards. Collectively, the Gower Handbook of Programme Management is most comprehensive guide to the subject that you can buy.

Handbook of Smart Coatings for Materials Protection

Handbook of Smart Coatings for Materials Protection
Author: Abdel Salam Hamdy Makhlouf
Publsiher: Elsevier
Total Pages: 656
Release: 2014-02-22
ISBN 10: 0857096885
ISBN 13: 9780857096883
Language: EN, FR, DE, ES & NL

Handbook of Smart Coatings for Materials Protection Book Review:

A smart coating is defined as one that changes its properties in response to an environmental stimulus. The Handbook of Smart Coatings for Materials Protection reviews the new generation of smart coatings for corrosion and other types of material protection. Part one explores the fundamentals of smart coatings for materials protection including types, materials, design, and processing. Chapters review corrosion processes and strategies for prevention; smart coatings for corrosion protection; techniques for synthesizing and applying smart coatings; multi-functional, self-healing coatings; and current and future trends of protective coatings for automotive, aerospace, and military applications. Chapters in part two focus on smart coatings with self-healing properties for corrosion protection, including self-healing anticorrosion coatings for structural and petrochemical engineering applications; smart self-healing coatings for corrosion protection of aluminum alloys, magnesium alloys and steel; smart nanocoatings for corrosion detection and control; and recent advances in polyaniline-based organic coatings for corrosion protection. Chapters in part three move on to highlight other types of smart coatings, including smart self-cleaning coatings for corrosion protection; smart polymer nanocomposite water- and oil-repellent coatings for aluminum; UV-curable organic polymer coatings for corrosion protection of steel; smart epoxy coatings for early detection of corrosion in steel and aluminum; and structural ceramics with self-healing properties. The Handbook of Smart Coatings for Materials Protection is a valuable reference for those concerned with preventing corrosion, particularly of metals, professionals working within the surface coating industries, as well as all those with an academic research interest in the field. Reviews the new generation of smart coatings for corrosion and other types of material protection Explores the fundamentals of smart coatings for materials protection including types, materials, design, and processing Includes a focus on smart coatings with self-healing properties for corrosion protection

Composites Manufacturing

Composites Manufacturing
Author: Sanjay Mazumdar
Publsiher: CRC Press
Total Pages: 416
Release: 2001-12-27
ISBN 10: 1420041983
ISBN 13: 9781420041989
Language: EN, FR, DE, ES & NL

Composites Manufacturing Book Review:

More and more companies manufacture reinforced composite products. To meet the market need, researchers and industries are developing manufacturing methods without a reference that thoroughly covers the manufacturing guidelines. Composites Manufacturing: Materials, Product, and Process Engineering fills this void. The author presents a fundamental classification of processes, helping you understand where a process fits within the overall scheme and which process is best suited for a particular component. You will understand: Types of raw materials available for the fabrication of composite products Methods of selecting right material for an application Six important phases of a product development process Design for manufacturing (DFM) approach for integrating benefits and capabilities of the manufacturing process into design of the product so that the best product can be produced in a shortest possible time and with limited resources Detailed description of composites manufacturing processes with some case studies on actual part making such as boat hulls, bathtubs, fishing rods and more Process models and process selection criteria Design and manufacturing guidelines for making cost-competitive composite products Procedures for writing manufacturing instructions and bill of materials Joining and machining techniques for composite materials Cost-estimating techniques and methods of comparing technologies/manufacturing processes based on cost Recycling approach to deal with post-market composite products To stay ahead in this quickly changing field, you need information you can trust. You need Composites Manufacturing: Materials, Product, and Process Engineering.