Author: Andrew Okungbowa
Publisher: Apress
ISBN: 1484207165
Category : Computers
Languages : en
Pages : 579
Book Description
SAP ERP modules are notoriously hard to configure and use effectively without a lot of practice and experience. But as SAP ERP Financial Accounting and Controlling: Configuration and Use Management shows, it doesn't have to be so difficult. The book takes a systematic approach that leads SAP Financial Accounting and Controlling (FICO) users step by step through configuring and using all the program’s facets. This approach makes configuration complexities manageable. The book’s author—SAP expert, trainer, and accountant Andrew Okungbowa—ensures that both you and your end users are up and running quickly and confidently with FICO. He also provides sound and tested procedures that ensure your implementation works without error. SAP ERP Financial Accounting and Controlling: Configuration and Use Management is in fact the most comprehensive and easy-to-follow SAP FICO configuration book in the market. It incorporates a hands-on approach, with hundreds of screen shots and practical examples, that allows a person without prior configuration training to make SAP FICO ready for use in the enterprise. You’ll find that you don’t need to be a rocket scientist to grasp the concepts explained and apply them to your work—even when the finances are complicated, such as with the ins and outs of taxes, currency conversions, or special general ledger entries such as down payments or bills of exchange. Providing an in-depth coverage of both configuration and end user procedures, the book covers most aspects of the SAP FICO certification syllabus—SAP’s view of the module’s key tasks and procedures—including: Configuring and using the general ledger and accounts payable and receivable screens Configuring and completing closing procedures, asset accounting, and financial reporting Configuring global settings and enterprise variables Accounting for both profit and cost centers Creating a house bank Integrating FICO with other SAP modules Taking a jargon-free tone and providing an abundance of examples, Andrew Okungbowa provides a clear understanding of configuration techniques and the breadth of functionalities encompassed by SAP FICO. And as an accountant, Okungbowa understands the needs of end users as well as of those answering to the CIO.
SAP ERP Financial Accounting and Controlling
Author: Andrew Okungbowa
Publisher: Apress
ISBN: 1484207165
Category : Computers
Languages : en
Pages : 579
Book Description
SAP ERP modules are notoriously hard to configure and use effectively without a lot of practice and experience. But as SAP ERP Financial Accounting and Controlling: Configuration and Use Management shows, it doesn't have to be so difficult. The book takes a systematic approach that leads SAP Financial Accounting and Controlling (FICO) users step by step through configuring and using all the program’s facets. This approach makes configuration complexities manageable. The book’s author—SAP expert, trainer, and accountant Andrew Okungbowa—ensures that both you and your end users are up and running quickly and confidently with FICO. He also provides sound and tested procedures that ensure your implementation works without error. SAP ERP Financial Accounting and Controlling: Configuration and Use Management is in fact the most comprehensive and easy-to-follow SAP FICO configuration book in the market. It incorporates a hands-on approach, with hundreds of screen shots and practical examples, that allows a person without prior configuration training to make SAP FICO ready for use in the enterprise. You’ll find that you don’t need to be a rocket scientist to grasp the concepts explained and apply them to your work—even when the finances are complicated, such as with the ins and outs of taxes, currency conversions, or special general ledger entries such as down payments or bills of exchange. Providing an in-depth coverage of both configuration and end user procedures, the book covers most aspects of the SAP FICO certification syllabus—SAP’s view of the module’s key tasks and procedures—including: Configuring and using the general ledger and accounts payable and receivable screens Configuring and completing closing procedures, asset accounting, and financial reporting Configuring global settings and enterprise variables Accounting for both profit and cost centers Creating a house bank Integrating FICO with other SAP modules Taking a jargon-free tone and providing an abundance of examples, Andrew Okungbowa provides a clear understanding of configuration techniques and the breadth of functionalities encompassed by SAP FICO. And as an accountant, Okungbowa understands the needs of end users as well as of those answering to the CIO.
Publisher: Apress
ISBN: 1484207165
Category : Computers
Languages : en
Pages : 579
Book Description
SAP ERP modules are notoriously hard to configure and use effectively without a lot of practice and experience. But as SAP ERP Financial Accounting and Controlling: Configuration and Use Management shows, it doesn't have to be so difficult. The book takes a systematic approach that leads SAP Financial Accounting and Controlling (FICO) users step by step through configuring and using all the program’s facets. This approach makes configuration complexities manageable. The book’s author—SAP expert, trainer, and accountant Andrew Okungbowa—ensures that both you and your end users are up and running quickly and confidently with FICO. He also provides sound and tested procedures that ensure your implementation works without error. SAP ERP Financial Accounting and Controlling: Configuration and Use Management is in fact the most comprehensive and easy-to-follow SAP FICO configuration book in the market. It incorporates a hands-on approach, with hundreds of screen shots and practical examples, that allows a person without prior configuration training to make SAP FICO ready for use in the enterprise. You’ll find that you don’t need to be a rocket scientist to grasp the concepts explained and apply them to your work—even when the finances are complicated, such as with the ins and outs of taxes, currency conversions, or special general ledger entries such as down payments or bills of exchange. Providing an in-depth coverage of both configuration and end user procedures, the book covers most aspects of the SAP FICO certification syllabus—SAP’s view of the module’s key tasks and procedures—including: Configuring and using the general ledger and accounts payable and receivable screens Configuring and completing closing procedures, asset accounting, and financial reporting Configuring global settings and enterprise variables Accounting for both profit and cost centers Creating a house bank Integrating FICO with other SAP modules Taking a jargon-free tone and providing an abundance of examples, Andrew Okungbowa provides a clear understanding of configuration techniques and the breadth of functionalities encompassed by SAP FICO. And as an accountant, Okungbowa understands the needs of end users as well as of those answering to the CIO.
Gideon the Ninth
Author: Tamsyn Muir
Publisher: Tordotcom
ISBN: 1250313171
Category : Fiction
Languages : en
Pages : 374
Book Description
Gideon the Ninth is the first book in the New York Times and USA Today Bestselling Locked Tomb Series, and one of the Best Books of 2019 according to NPR, the New York Public Library, Amazon, BookPage, Shelf Awareness, BookRiot, and Bustle! WINNER of the 2020 Locus Award and Crawford Award Finalist for the 2023 Hugo Award for Best Series! Finalist for the 2020 Hugo, Nebula, Dragon, and World Fantasy Awards “Unlike anything I’ve ever read. ” —V.E. Schwab “Lesbian necromancers explore a haunted gothic palace in space!” —Charles Stross “Deft, tense and atmospheric, compellingly immersive and wildly original.” —The New York Times The Emperor needs necromancers. The Ninth Necromancer needs a swordswoman. Gideon has a sword, some dirty magazines, and no more time for undead nonsense. Tamsyn Muir’s Gideon the Ninth unveils a solar system of swordplay, cut-throat politics, and lesbian necromancers. Her characters leap off the page, as skillfully animated as arcane revenants. The result is a heart-pounding epic science fantasy. Brought up by unfriendly, ossifying nuns, ancient retainers, and countless skeletons, Gideon is ready to abandon a life of servitude and an afterlife as a reanimated corpse. She packs up her sword, her shoes, and her dirty magazines, and prepares to launch her daring escape. But her childhood nemesis won’t set her free without a service. Harrowhark Nonagesimus, Reverend Daughter of the Ninth House and bone witch extraordinaire, has been summoned into action. The Emperor has invited the heirs to each of his loyal Houses to a deadly trial of wits and skill. If Harrowhark succeeds she will be become an immortal, all-powerful servant of the Resurrection, but no necromancer can ascend without their cavalier. Without Gideon’s sword, Harrow will fail, and the Ninth House will die. Of course, some things are better left dead. THE LOCKED TOMB SERIES BOOK 1: Gideon the Ninth BOOK 2: Harrow the Ninth BOOK 3: Nona the Ninth BOOK 4: Alecto the Ninth At the Publisher's request, this title is being sold without Digital Rights Management Software (DRM) applied.
Publisher: Tordotcom
ISBN: 1250313171
Category : Fiction
Languages : en
Pages : 374
Book Description
Gideon the Ninth is the first book in the New York Times and USA Today Bestselling Locked Tomb Series, and one of the Best Books of 2019 according to NPR, the New York Public Library, Amazon, BookPage, Shelf Awareness, BookRiot, and Bustle! WINNER of the 2020 Locus Award and Crawford Award Finalist for the 2023 Hugo Award for Best Series! Finalist for the 2020 Hugo, Nebula, Dragon, and World Fantasy Awards “Unlike anything I’ve ever read. ” —V.E. Schwab “Lesbian necromancers explore a haunted gothic palace in space!” —Charles Stross “Deft, tense and atmospheric, compellingly immersive and wildly original.” —The New York Times The Emperor needs necromancers. The Ninth Necromancer needs a swordswoman. Gideon has a sword, some dirty magazines, and no more time for undead nonsense. Tamsyn Muir’s Gideon the Ninth unveils a solar system of swordplay, cut-throat politics, and lesbian necromancers. Her characters leap off the page, as skillfully animated as arcane revenants. The result is a heart-pounding epic science fantasy. Brought up by unfriendly, ossifying nuns, ancient retainers, and countless skeletons, Gideon is ready to abandon a life of servitude and an afterlife as a reanimated corpse. She packs up her sword, her shoes, and her dirty magazines, and prepares to launch her daring escape. But her childhood nemesis won’t set her free without a service. Harrowhark Nonagesimus, Reverend Daughter of the Ninth House and bone witch extraordinaire, has been summoned into action. The Emperor has invited the heirs to each of his loyal Houses to a deadly trial of wits and skill. If Harrowhark succeeds she will be become an immortal, all-powerful servant of the Resurrection, but no necromancer can ascend without their cavalier. Without Gideon’s sword, Harrow will fail, and the Ninth House will die. Of course, some things are better left dead. THE LOCKED TOMB SERIES BOOK 1: Gideon the Ninth BOOK 2: Harrow the Ninth BOOK 3: Nona the Ninth BOOK 4: Alecto the Ninth At the Publisher's request, this title is being sold without Digital Rights Management Software (DRM) applied.
The SAP R/3 Handbook
Author: José Antonio Hernández
Publisher: McGraw-Hill/Osborne Media
ISBN: 9780071354134
Category : Business
Languages : en
Pages : 0
Book Description
Whether readers seek an introduction or in-depth knowledge of SAP R/3, this handbook fits the bill, covering programming, data modeling, systems architecture, installation, and system administration.
Publisher: McGraw-Hill/Osborne Media
ISBN: 9780071354134
Category : Business
Languages : en
Pages : 0
Book Description
Whether readers seek an introduction or in-depth knowledge of SAP R/3, this handbook fits the bill, covering programming, data modeling, systems architecture, installation, and system administration.
Department of Defense Dictionary of Military and Associated Terms
Author: United States. Joint Chiefs of Staff
Publisher:
ISBN:
Category : Military art and science
Languages : en
Pages : 392
Book Description
Publisher:
ISBN:
Category : Military art and science
Languages : en
Pages : 392
Book Description
Distributed Optimization and Statistical Learning Via the Alternating Direction Method of Multipliers
Author: Stephen Boyd
Publisher: Now Publishers Inc
ISBN: 160198460X
Category : Computers
Languages : en
Pages : 138
Book Description
Surveys the theory and history of the alternating direction method of multipliers, and discusses its applications to a wide variety of statistical and machine learning problems of recent interest, including the lasso, sparse logistic regression, basis pursuit, covariance selection, support vector machines, and many others.
Publisher: Now Publishers Inc
ISBN: 160198460X
Category : Computers
Languages : en
Pages : 138
Book Description
Surveys the theory and history of the alternating direction method of multipliers, and discusses its applications to a wide variety of statistical and machine learning problems of recent interest, including the lasso, sparse logistic regression, basis pursuit, covariance selection, support vector machines, and many others.
Bioprocess Engineering Principles
Author: Pauline M. Doran
Publisher: Elsevier
ISBN: 0080528120
Category : Science
Languages : en
Pages : 455
Book Description
The emergence and refinement of techniques in molecular biology has changed our perceptions of medicine, agriculture and environmental management. Scientific breakthroughs in gene expression, protein engineering and cell fusion are being translated by a strengthening biotechnology industry into revolutionary new products and services. Many a student has been enticed by the promise of biotechnology and the excitement of being near the cutting edge of scientific advancement. However, graduates trained in molecular biology and cell manipulation soon realise that these techniques are only part of the picture. Reaping the full benefits of biotechnology requires manufacturing capability involving the large-scale processing of biological material. Increasingly, biotechnologists are being employed by companies to work in co-operation with chemical engineers to achieve pragmatic commercial goals. For many years aspects of biochemistry and molecular genetics have been included in chemical engineering curricula, yet there has been little attempt until recently to teach aspects of engineering applicable to process design to biotechnologists.This textbook is the first to present the principles of bioprocess engineering in a way that is accessible to biological scientists. Other texts on bioprocess engineering currently available assume that the reader already has engineering training. On the other hand, chemical engineering textbooks do not consider examples from bioprocessing, and are written almost exclusively with the petroleum and chemical industries in mind. This publication explains process analysis from an engineering point of view, but refers exclusively to the treatment of biological systems. Over 170 problems and worked examples encompass a wide range of applications, including recombinant cells, plant and animal cell cultures, immobilised catalysts as well as traditional fermentation systems.* * First book to present the principles of bioprocess engineering in a way that is accessible to biological scientists* Explains process analysis from an engineering point of view, but uses worked examples relating to biological systems* Comprehensive, single-authored* 170 problems and worked examples encompass a wide range of applications, involving recombinant plant and animal cell cultures, immobilized catalysts, and traditional fermentation systems* 13 chapters, organized according to engineering sub-disciplines, are groupled in four sections - Introduction, Material and Energy Balances, Physical Processes, and Reactions and Reactors* Each chapter includes a set of problems and exercises for the student, key references, and a list of suggestions for further reading* Includes useful appendices, detailing conversion factors, physical and chemical property data, steam tables, mathematical rules, and a list of symbols used* Suitable for course adoption - follows closely curricula used on most bioprocessing and process biotechnology courses at senior undergraduate and graduate levels.
Publisher: Elsevier
ISBN: 0080528120
Category : Science
Languages : en
Pages : 455
Book Description
The emergence and refinement of techniques in molecular biology has changed our perceptions of medicine, agriculture and environmental management. Scientific breakthroughs in gene expression, protein engineering and cell fusion are being translated by a strengthening biotechnology industry into revolutionary new products and services. Many a student has been enticed by the promise of biotechnology and the excitement of being near the cutting edge of scientific advancement. However, graduates trained in molecular biology and cell manipulation soon realise that these techniques are only part of the picture. Reaping the full benefits of biotechnology requires manufacturing capability involving the large-scale processing of biological material. Increasingly, biotechnologists are being employed by companies to work in co-operation with chemical engineers to achieve pragmatic commercial goals. For many years aspects of biochemistry and molecular genetics have been included in chemical engineering curricula, yet there has been little attempt until recently to teach aspects of engineering applicable to process design to biotechnologists.This textbook is the first to present the principles of bioprocess engineering in a way that is accessible to biological scientists. Other texts on bioprocess engineering currently available assume that the reader already has engineering training. On the other hand, chemical engineering textbooks do not consider examples from bioprocessing, and are written almost exclusively with the petroleum and chemical industries in mind. This publication explains process analysis from an engineering point of view, but refers exclusively to the treatment of biological systems. Over 170 problems and worked examples encompass a wide range of applications, including recombinant cells, plant and animal cell cultures, immobilised catalysts as well as traditional fermentation systems.* * First book to present the principles of bioprocess engineering in a way that is accessible to biological scientists* Explains process analysis from an engineering point of view, but uses worked examples relating to biological systems* Comprehensive, single-authored* 170 problems and worked examples encompass a wide range of applications, involving recombinant plant and animal cell cultures, immobilized catalysts, and traditional fermentation systems* 13 chapters, organized according to engineering sub-disciplines, are groupled in four sections - Introduction, Material and Energy Balances, Physical Processes, and Reactions and Reactors* Each chapter includes a set of problems and exercises for the student, key references, and a list of suggestions for further reading* Includes useful appendices, detailing conversion factors, physical and chemical property data, steam tables, mathematical rules, and a list of symbols used* Suitable for course adoption - follows closely curricula used on most bioprocessing and process biotechnology courses at senior undergraduate and graduate levels.
Introduction to Permanent Plug and Abandonment of Wells
Author: Mahmoud Khalifeh
Publisher: Springer Nature
ISBN: 3030399702
Category : Technology & Engineering
Languages : en
Pages : 285
Book Description
This open access book offers a timely guide to challenges and current practices to permanently plug and abandon hydrocarbon wells. With a focus on offshore North Sea, it analyzes the process of plug and abandonment of hydrocarbon wells through the establishment of permanent well barriers. It provides the reader with extensive knowledge on the type of barriers, their functioning and verification. It then discusses plug and abandonment methodologies, analyzing different types of permanent plugging materials. Last, it describes some tests for verifying the integrity and functionality of installed permanent barriers. The book offers a comprehensive reference guide to well plugging and abandonment (P&A) and well integrity testing. The book also presents new technologies that have been proposed to be used in plugging and abandoning of wells, which might be game-changing technologies, but they are still in laboratory or testing level. Given its scope, it addresses students and researchers in both academia and industry. It also provides information for engineers who work in petroleum industry and should be familiarized with P&A of hydrocarbon wells to reduce the time of P&A by considering it during well planning and construction.
Publisher: Springer Nature
ISBN: 3030399702
Category : Technology & Engineering
Languages : en
Pages : 285
Book Description
This open access book offers a timely guide to challenges and current practices to permanently plug and abandon hydrocarbon wells. With a focus on offshore North Sea, it analyzes the process of plug and abandonment of hydrocarbon wells through the establishment of permanent well barriers. It provides the reader with extensive knowledge on the type of barriers, their functioning and verification. It then discusses plug and abandonment methodologies, analyzing different types of permanent plugging materials. Last, it describes some tests for verifying the integrity and functionality of installed permanent barriers. The book offers a comprehensive reference guide to well plugging and abandonment (P&A) and well integrity testing. The book also presents new technologies that have been proposed to be used in plugging and abandoning of wells, which might be game-changing technologies, but they are still in laboratory or testing level. Given its scope, it addresses students and researchers in both academia and industry. It also provides information for engineers who work in petroleum industry and should be familiarized with P&A of hydrocarbon wells to reduce the time of P&A by considering it during well planning and construction.
The Symbolic Species: The Co-evolution of Language and the Brain
Author: Terrence W. Deacon
Publisher: W. W. Norton & Company
ISBN: 0393343022
Category : Science
Languages : en
Pages : 532
Book Description
"A work of enormous breadth, likely to pleasantly surprise both general readers and experts."—New York Times Book Review This revolutionary book provides fresh answers to long-standing questions of human origins and consciousness. Drawing on his breakthrough research in comparative neuroscience, Terrence Deacon offers a wealth of insights into the significance of symbolic thinking: from the co-evolutionary exchange between language and brains over two million years of hominid evolution to the ethical repercussions that followed man's newfound access to other people's thoughts and emotions. Informing these insights is a new understanding of how Darwinian processes underlie the brain's development and function as well as its evolution. In contrast to much contemporary neuroscience that treats the brain as no more or less than a computer, Deacon provides a new clarity of vision into the mechanism of mind. It injects a renewed sense of adventure into the experience of being human.
Publisher: W. W. Norton & Company
ISBN: 0393343022
Category : Science
Languages : en
Pages : 532
Book Description
"A work of enormous breadth, likely to pleasantly surprise both general readers and experts."—New York Times Book Review This revolutionary book provides fresh answers to long-standing questions of human origins and consciousness. Drawing on his breakthrough research in comparative neuroscience, Terrence Deacon offers a wealth of insights into the significance of symbolic thinking: from the co-evolutionary exchange between language and brains over two million years of hominid evolution to the ethical repercussions that followed man's newfound access to other people's thoughts and emotions. Informing these insights is a new understanding of how Darwinian processes underlie the brain's development and function as well as its evolution. In contrast to much contemporary neuroscience that treats the brain as no more or less than a computer, Deacon provides a new clarity of vision into the mechanism of mind. It injects a renewed sense of adventure into the experience of being human.
Probabilistic Robotics
Author: Sebastian Thrun
Publisher: MIT Press
ISBN: 0262201623
Category : Technology & Engineering
Languages : en
Pages : 668
Book Description
An introduction to the techniques and algorithms of the newest field in robotics. Probabilistic robotics is a new and growing area in robotics, concerned with perception and control in the face of uncertainty. Building on the field of mathematical statistics, probabilistic robotics endows robots with a new level of robustness in real-world situations. This book introduces the reader to a wealth of techniques and algorithms in the field. All algorithms are based on a single overarching mathematical foundation. Each chapter provides example implementations in pseudo code, detailed mathematical derivations, discussions from a practitioner's perspective, and extensive lists of exercises and class projects. The book's Web site, www.probabilistic-robotics.org, has additional material. The book is relevant for anyone involved in robotic software development and scientific research. It will also be of interest to applied statisticians and engineers dealing with real-world sensor data.
Publisher: MIT Press
ISBN: 0262201623
Category : Technology & Engineering
Languages : en
Pages : 668
Book Description
An introduction to the techniques and algorithms of the newest field in robotics. Probabilistic robotics is a new and growing area in robotics, concerned with perception and control in the face of uncertainty. Building on the field of mathematical statistics, probabilistic robotics endows robots with a new level of robustness in real-world situations. This book introduces the reader to a wealth of techniques and algorithms in the field. All algorithms are based on a single overarching mathematical foundation. Each chapter provides example implementations in pseudo code, detailed mathematical derivations, discussions from a practitioner's perspective, and extensive lists of exercises and class projects. The book's Web site, www.probabilistic-robotics.org, has additional material. The book is relevant for anyone involved in robotic software development and scientific research. It will also be of interest to applied statisticians and engineers dealing with real-world sensor data.
The Praetorian STARShip : the untold story of the Combat Talon
Author:
Publisher: DIANE Publishing
ISBN: 1428990437
Category :
Languages : en
Pages : 507
Book Description
Jerry Thigpen's study on the history of the Combat Talon is the first effort to tell the story of this wonderfully capable machine. This weapons system has performed virtually every imaginable tactical event in the spectrum of conflict and by any measure is the most versatile C-130 derivative ever produced. First modified and sent to Southeast Asia (SEA) in 1966 to replace theater unconventional warfare (UW) assets that were limited in both lift capability and speed the Talon I quickly adapted to theater UW tasking including infiltration and resupply and psychological warfare operations into North Vietnam. After spending four years in SEA and maturing into a highly respected UW weapons system the Joint Chief of Staff (JCS) chose the Combat Talon to lead the night low-level raid on the North Vietnamese prison camp at Son Tay. Despite the outcome of the operation the Talon I cemented its reputation as the weapons system of choice for long-range clandestine operations. In the period following the Vietnam War United States Air Force (USAF) special operations gradually lost its political and financial support which was graphically demonstrated in the failed Desert One mission into Iran. Thanks to congressional supporters like Earl Hutto of Florida and Dan Daniel of Virginia funds for aircraft upgrades and military construction projects materialized to meet the ever-increasing threat to our nation. Under the leadership of such committed hard-driven officers as Brenci Uttaro Ferkes Meller and Thigpen the crew force became the most disciplined in our Air Force. It was capable of penetrating hostile airspace at night in a low-level mountainous environment covertly to execute any number of unconventional warfare missions.
Publisher: DIANE Publishing
ISBN: 1428990437
Category :
Languages : en
Pages : 507
Book Description
Jerry Thigpen's study on the history of the Combat Talon is the first effort to tell the story of this wonderfully capable machine. This weapons system has performed virtually every imaginable tactical event in the spectrum of conflict and by any measure is the most versatile C-130 derivative ever produced. First modified and sent to Southeast Asia (SEA) in 1966 to replace theater unconventional warfare (UW) assets that were limited in both lift capability and speed the Talon I quickly adapted to theater UW tasking including infiltration and resupply and psychological warfare operations into North Vietnam. After spending four years in SEA and maturing into a highly respected UW weapons system the Joint Chief of Staff (JCS) chose the Combat Talon to lead the night low-level raid on the North Vietnamese prison camp at Son Tay. Despite the outcome of the operation the Talon I cemented its reputation as the weapons system of choice for long-range clandestine operations. In the period following the Vietnam War United States Air Force (USAF) special operations gradually lost its political and financial support which was graphically demonstrated in the failed Desert One mission into Iran. Thanks to congressional supporters like Earl Hutto of Florida and Dan Daniel of Virginia funds for aircraft upgrades and military construction projects materialized to meet the ever-increasing threat to our nation. Under the leadership of such committed hard-driven officers as Brenci Uttaro Ferkes Meller and Thigpen the crew force became the most disciplined in our Air Force. It was capable of penetrating hostile airspace at night in a low-level mountainous environment covertly to execute any number of unconventional warfare missions.