Conference Session

Trends in Mechanical Engineering II

Collection

2010 Annual Conference & Exposition

Authors

Kuntinee Maneeratana, Chulalongkorn University; Angkee Sripakagorn, Chulalongkorn University

Tagged Divisions

Mechanical Engineering

AC 2010-1187: KEY SUBJECT INDICATORS AND ADMISSION IMPACT FROMSUBJECT GRADES IN MECHANICAL ENGINEERING-BASED BACHELORPROGRAMS AT CHULALONGKORN UNIVERSITYKuntinee Maneeratana, Chulalongkorn University Kuntinee Maneeratana is an Associate Professor in Mechanical Engineering at Chulalongkorn University, Thailand. She earned a Ph.D. and a B.Eng. in Mechanical Engineering, both from Imperial College of Science, Technology and Medicine, UK as well as a B.Ed. in Educational Measurement and Evaluation from Sukhothai Thammathirat Open University, Thailand. Her area of expertise is computational mechanics.Angkee Sripakagorn, Chulalongkorn University Angkee Sripakagorn is an Assistant Professor in

Conference Session

Design in BME Education

Collection

2010 Annual Conference & Exposition

Authors

Eric Kennedy, Bucknell University; Donna Ebenstein, Bucknell University

Tagged Divisions

Biomedical

part.Preliminary student assessment indicates that the students feel that designing, rapid prototyping,and physically producing the Cube of Knowledge was both a valuable and enjoyable experience.The vast majority of students agree that the project experience will be valuable for senior designand their future engineering careers. Additionally, they indicated that they would like to see themodule expanded to include a larger variety of fabrication techniques and more time for basicskill development.IntroductionGiven the broad spectrum of topics that must be addressed in an undergraduate biomedicalengineering (BME) curriculum it is difficult to provide adequate exposure to students in designand manufacturing technology such as computer-aided design (CAD) and

Conference Session

Pedagogical Developments in BME

Collection

2010 Annual Conference & Exposition

Authors

Elizabeth Vargis, Vanderbilt University; Anita Mahadevan-Jansen, Vanderbilt University

Tagged Divisions

Biomedical

lastdecade, optical sciences and technologies have been widely developed for new applications anddevices, both for basic science research as well as clinical settings. However, at the same time,biomedical optics courses have not been well-integrated into most undergrad biomedicalengineering curriculums. At Vanderbilt University, a junior to senior-level biomedicalengineering elective course entitled “Introduction to Biomedical Optics” has been developedwith the objective of “using light from the far-ultraviolet through the visible into the infrared fordiagnostic, therapeutic, and sensing applications in medicine and biology.”1Previous work in the development of this course focused on creating and implementing aninteractive instruction module of

Conference Session

Frontiers in Engineering Economy

Collection

2010 Annual Conference & Exposition

Authors

Neal Lewis, University of Bridgeport; Ted Eschenbach, TGE Consulting; Joseph Hartman, University of Florida

Tagged Divisions

Engineering Economy

process by laying out the alternatives in a clear manner. These topics should be taught inthe undergraduate course. Risk management is a necessary part of project funding, and this isappropriate for the undergraduate curriculum. Inclusion as an application of decision trees is alogical and worthwhile application, and we are pleased to see that most authors include thematerial in their texts.Use of options analysis should be reserved for graduate courses. Use of options analysis inmulti-stage project analysis is a fairly limited area, and is still not fully understood (althoughthere is available literature that may allow you to calculate a project value). Where this is taught,the current methods need to be accompanied by the concerns and

Conference Session

New Collaborations

Collection

2010 Annual Conference & Exposition

Authors

Megan Sapp Nelson, Purdue University; Michael Fosmire, Purdue University Libraries -- PHYS

Tagged Divisions

Engineering Libraries

literacy objectives into a freshman,sophomore, junior, and senior level chemical engineering course series, by linking informationliteracy standard criteria to existing course assignments.17, 19 Riley et al. redesigned the entiredepartmental curriculum while including an information literacy/lifelong learning componentacross the curriculum.20Many librarians and faculty focus curricular redesign around the ALA/ACRL/STS Standards forInformation Literacy in Science and Technology.15, 17, 18, 21 Trussell examined ABET 2000+ inlight of existing information literacy practice.22 Riley compared ABET Criterion 3, ALAStandards for Information Literacy and the curriculum outcomes for a redesign of the SmithCollege curriculum to insure integration of

Conference Session

Experiential Learning in BME

Collection

2010 Annual Conference & Exposition

Authors

Michele Wabler, Clemson University; Estefania Alvarez, Clemson University; John DesJardins, Clemson University

Tagged Divisions

Biomedical

undergraduate student in topics of medical devices, biomaterials, and clinicalanatomy. This paper details the development, application, and assessment of a mentoredundergraduate teaching and research program known as Creative Inquiry at Clemson Universitythat is focused on the development of a statewide implant retrieval program for educational andresearch purposes.IntroductionThe mission of the Department of Bioengineering at Clemson University is to provide anoutstanding education for engineers in bioengineering and developing future leaders. With thismission in mind, three goals were identified: 1) to provide students with the education needed fora rewarding career, 2) to provide an intellectually rigorous undergraduate education thatemphasizes

Conference Session

Engineering Professional Development for K-12 Teachers

Collection

2010 Annual Conference & Exposition

Authors

Augusto Macalalag, Stevens Institute of Technology; Susan Lowes, Teachers College/Columbia University; Karen Guo, Teachers College/Columbia University; Devayani Tirthali, Teachers College/Columbia University; Mercedes McKay, Stevens Institute of Technology; Elisabeth McGrath, Stevens Institute of Technology

Tagged Divisions

K-12 & Pre-College Engineering

thinking, collaboration, and communication among students. Finally,further data analysis revealed that the number of PISA lessons that teachers implemented in theirclassrooms was a significant predictor of students’ test scores. In this paper, we report on theprofessional development model that we used and the results of our study.IntroductionExemplary professional development (PD) for teachers can have a positive impact on students’learning and the classroom environment. Specifically, Blank & de las Alas1 found successful PDexperiences for math teachers contributed to an increase in teachers’ subject knowledge,pedagogy, and students’ content knowledge. However, teacher PD that focuses on integratingscience and engineering in elementary

Conference Session

Frontiers in Engineering Management

Collection

2010 Annual Conference & Exposition

Authors

William Loendorf, Eastern Washington University

Tagged Divisions

Engineering Management

AC 2010-1394: ENGINEERING MANAGEMENT PERFORMANCE MONITORINGMETHODS UTILIZED BY MANUFACTURERS TO BECOME MORECOMPETITIVEWilliam Loendorf, Eastern Washington University William R. Loendorf is currently an Associate Professor of Engineering & Design at Eastern Washington University. He obtained his B.Sc. in Engineering Science at the University of Wisconsin - Parkside, M.S. in Electrical Engineering at Colorado State University, M.B.A. at the Lake Forest Graduate School of Management, and Ph.D. in Engineering Management at Walden University. He holds a Professional Engineer license and has 30 years of industrial experience as an Engineer or Engineering Manager at General Motors, Cadnetix, and

Conference Session

Chemical Engineering Education: Underclass Years

Collection

2010 Annual Conference & Exposition

Authors

Kwannin Kuo, Lunghwa University of Science and Technology; Pao-Chi Chen, Lunghwa University Science and Technology; Meei-Ruey Hsu, Ming-Chuan University

Tagged Divisions

Chemical Engineering

-19.Hill, J. W. & Petrucci, R. H. (1999, 2th edn.). General Chemistry: An Integrated Approach, Upper Saddle River, NJ: Prentice Hall Inc.James R., MacArthur and Loretta L. Jones (2008). A review of literature reports of clickers applicable to college chemistry classrooms, Chem. Educ. Res. Pract., 9, 187-195.Kim B., Saalman E., Christie M., Ingerman A. & Linder C. (2008). SimChemistry as an active learning tool in chemistry education, Chem. Educ. Res. Pract., 9, 277-284.Kuo, K. (2009). The academic performances of senior and vocational high school graduate students in the department of Chemical and Material Engineering of Lunghwa University, Journal of Lunghwa University of Science and Technology, 28, 39-51.Lewis, R. (2004

Conference Session

Frontiers in Engineering Management

Collection

2010 Annual Conference & Exposition

Authors

William Loendorf, Eastern Washington University

Tagged Divisions

Engineering Management

included in theengineering and engineering technology curriculum. The findings indicate that American toolshops are using innovative technologies, updating machinery, and instituting new strategies. Thetool shops making this transition are the adaptors creating new competitive advantages byrevising their strategies to reflect competitive changes, offering products fitting into uniqueniches, supplying specialized customer services, and providing rapid delivery. The results fromthis study have been incorporated into engineering and engineering technology courses to betterprepare graduates for careers in engineering management for manufacturing based industries.IntroductionForeign competition has had an extremely negative impact on American

Conference Session

Contemporary Issues in Engineering Ethics

Collection

2010 Annual Conference & Exposition

Authors

Alejandra J. Magana, Purdue University, West Lafayette; Donna Riley, Smith College

Tagged Divisions

Engineering Ethics

(2001) discussed the role of the NNI as abroker in coordinating research and development in nanotechnology together with public hopesand fears. They also commented that the NNI should embrace the goal of building capacity forpublic dialogue. Roco and Bainbridge also addressed the need for honesty when genuine risksare identified.Education and human development. Nanotechnology and its social, cultural scientific andtechnological consequences create an opportunity to integrate education across science,technology, social sciences and humanities (Roco and Bainbridge 2005) 7 . The end-result maybe informed, educated publics emerging from our high schools and colleges, able to shape thedirection of nanotechnology in beneficial ways (Roco and

Conference Session

Innovations in First Year Programs

Collection

2010 Annual Conference & Exposition

Authors

James Lewis, University of Louisville; Jeffrey Hieb, University of Louisville; David Wheatley, University of Louisville

Tagged Divisions

First-Year Programs

AC 2010-1278: INTRODUCING CRITICAL THINKING TO FRESHMANENGINEERING STUDENTSJames Lewis, University of Louisville James E. Lewis, Ph.D. is an Assistant Professor in the Department of Engineering Fundamentals in the J. B. Speed School of Engineering at the University of Louisville. His research interests include parallel and distributed computer systems, cryptography, engineering education, undergraduate retention and technology (Tablet PCs) used in the classroom.Jeffrey Hieb, University of Louisville Jeffrey L. Hieb, Ph.D. is Assistant Professor in the Department of Engineering Fundamentals at the University of Louisville, Louisville, Kentucky. His research interests include cyber security

Conference Session

Innovations in Materials Education

Collection

2010 Annual Conference & Exposition

Authors

Cindy Waters, North Carolina A&T State University; Stephen Krause, Arizona State University; Jacquelyn Kelly, Arizona State University

Tagged Divisions

Materials

AC 2010-956: “IT’S SO EASY A CAVEMAN CAN DO IT:” TEACHINGINTRODUCTORY MATERIAL SCIENCE FOR INCREASED STUDENTENGAGEMENT.Cindy Waters, North Carolina A&T State UniversityStephen Krause, Arizona State UniversityJacquelyn Kelly, Arizona State University Page 15.1390.1© American Society for Engineering Education, 2010“It’s so Easy a Caveman Can Do It:” Teaching Introductory Material Science for Increased Student Engagement.Education advocates and experts have a plethora of experiences and evidentiary researchverifying the importance of student engagement in the education process. The millennial studentis an expert at finding new tools and media resources to

Conference Session

Frontiers in Engineering Management

Collection

2010 Annual Conference & Exposition

Authors

William Loendorf, Eastern Washington University

Tagged Divisions

Engineering Management

occurring in the manufacturing andproduction sector. These exercises provided an immediate avenue for the direct application of thetopics under consideration. Page 15.493.11Case studies were also developed to put the student into a real-world situation where they have touse what they have learned to resolve the problem or issue. In each case, the students are to applytheir knowledge of improvement programs to the assigned projects and case studies; thenanalyze their effectiveness, suggest improvements, and implement them. Additional case studieswere developed from the study's findings and used as an integral part of the lecture anddiscussion sections

Conference Session

Women in K-12 Engineeering & Outreach Programs

Collection

2010 Annual Conference & Exposition

Authors

Heath Tims, Louisiana Tech University; Jim Nelson, Louisiana Tech University; Galen Turner, Louisiana Tech University; Missy Wooley, Ruston High School; Marvin Nelson, Benton High School

Tagged Divisions

K-12 & Pre-College Engineering

be able to integrate technical knowledge into real-worldsituations3. Many pre-engineering outreach/recruitment programs are centered on hands-onprojects, which is one of the most important characteristics of our programs. However, while77% of K12 engineering programs in the United States focus on students, only 46% focus on theteachers4. All of the K12 programs that are a part of our Integrated STEM Education ResearchCenter (ISERC) target both high school students and teachers. While engaging high schoolstudents in relevant and interesting engineering design projects has had an immediate impact onincreasing STEM enrollments at our university, we believe long-term impact is more likely toresult from the interactions and relationships

Conference Session

Opportunities and Challenges in Developing International Engineering Research

Collection

2010 Annual Conference & Exposition

Authors

Josef Rojter, Victoria University of Technology

Tagged Divisions

International

…An engineer is someone who usesmath and science to mess with the world by designing and making things that other folks canuse(pause)..And once you mess with the world, you’re responsible for the mess you made .This view had little to do with the engineering curriculum and education, but rather withignorance concerning the final destination of engineering graduates. Skobrook20 examinedstudents’ views of engineering prior enrolling in the course at University of Hull, and foundthat students’ preconceptions of engineering and engineering studies were at odds withreality. This is not surprising since studies21 in Britain showed that most sixth form studentshad little or a wrong perception of engineering as a career option. Peter Durchholz 22 in

Conference Session

Special Session: Impacts of Service in Engineering

Collection

2010 Annual Conference & Exposition

Authors

Olga Pierrakos, James Madison University; Eric Pappas, James Madison University

Tagged Divisions

Educational Research and Methods

Education, 2010 Special Session: Assessing Students’ Learning Outcomes during a Complex and Real-world Problem-based Service Learning (PBSL) Project in a Sophomore Engineering Design CourseAbstractAuthentic and real-world problem solving is an integral part of the engineering profession. Yet,current research indicates that engineering education is primarily focused on well-defined andwell-structured problems, which do not provide students the real-world relevance, context, norexperience in solving the types of problems required in the engineering profession. The additionof problem-based learning (PBL) methodologies to the engineering curriculum providesengineering programs the opportunity to introduce students to a variety

Conference Session

Outstanding Contributions - Mechanical Engineering Education

Collection

2010 Annual Conference & Exposition

Authors

Rajesh Bhaskaran, Cornell University

Tagged Divisions

Mechanical Engineering

practicing engineers, to applyindustrial-strength simulation software to obtain useful and reliable solutions to practicalengineering problems, an important skill for the modern engineering workforce. At the sametime, simulation offers the opportunity to enhance learning through an interactive, visual mediumand build excitement among students about engineering.2. Pedagogical ApproachA university-industry workshop, ISTEC 2008, on the Integration of Simulation Technology intothe Engineering Curriculum was organized in July 2008. The purpose of the workshop was tobuild a community of educators and practitioners collaborating on the deployment of simulation

Conference Session

Special Session: Next Generation Problem-Solving

Collection

2010 Annual Conference & Exposition

Authors

Eric Hamilton, United States Air Force Academy; Mary Besterfield-Sacre, University of Pittsburgh; Barbara Olds, Colorado School of Mines; Nora Siewiorek, University of Pittsburgh

Tagged Divisions

Educational Research and Methods

definitions orinterpretations, modeling emphasizes connected knowledge forms, adaptation of large ideasto new contexts, just-in-time learning, and complex reasoning in collaborativearrangements. An orientation around models and modeling is often referred to as a Models andModeling Perspective (MMP) (http://modelsandmodeling.net).Emphasis on modeling has a well-established history in the computer-supported collaborativelearning literature [9-12]. In science education, various curriculum projects [13] exemplify thistrend with the development of replacement modules across multiple areas of the high schoolcurriculum. Multiple new modeling oriented pedagogical frameworks have arisen from increasedattention towards enabling learners toexperience science

Conference Session

Technology-Enhanced Learning

Collection

2010 Annual Conference & Exposition

Authors

Diarmuid McCarthy, University of Limerick; Niall Seery, University of Limerick; Seamus Gordon, University of Limerick

Tagged Divisions

Continuing Professional Development

, representing an overall decline of 13% since 2000 3. Thebreakdown of these SET courses paints a bleaker picture with a more worryingdecline in acceptance to engineering and computing programmes. The rise inconstruction courses due the success of the building boom helps to mask the seriousdecline in the uptake of STEM courses. This has lead to a 10 % decline inEngineering and Technology graduates between 2005 and 2006 3. Page 15.273.4 Figure 3History of Technology educationTechnology was introduced into the second-level curriculum at Junior Cycle (12-15yrs – pre leaving Certificate) as a standalone subject in 1989 to equip

Collection

2010 Fall ASEE Middle Atlantic Section Conference

Authors

Dennis Silage

communications seems to be alaggard. An undergraduate curriculum in digital communications has been developed thatcouples the traditional analytical approach with the simulation of the system for further design,analysis, insight and motivation.Bit by Bit CommunicationDigital communication systems convey information from a source or transmitter over a channelto a sink or receiver. Modern communication systems often do so in the presence of additivechannel noise and mild to severe channel and system non-linearities which tend to corrupt thetransmission. Traditionally examining the performance of a digital communication system asonly a set of analytical expressions, even if noise and non-linearities can somehow be describedadequately, seems to provide

Conference Session

Collaborative Projects in Architectural Engineering Education

Collection

2010 Annual Conference & Exposition

Authors

Charlie Setterfield, Sinclair Community College; Eric Dunn, Sinclair Community College; Russell Marcks, Sinclair Community College

Tagged Divisions

Architectural

-disciplinary capstoneapproach was developed: ≠ Multiple discipline capstone ≠ Heightened collaboration ≠ Increased use of technology ≠ More complete building code complianceAs a result, a new capstone curriculum was developed to more closely simulate the industrytrend toward integrated project delivery. Spring 2009 was the first implementation of this newstrategy.G. Integrated Project Design/DeliveryIn an effort to prepare both students and faculty for the challenge of moving to a morecompletely Integrated Project Design/Delivery (IPD) model of capstone course, funding wassecured by the department chair to bring in an expert lecturer in IPD. While serving as aprofessor of architecture, this instructor has developed a broad background in

Collection

2010 ASEE Zone 1 Conference

Authors

Chiara Silvestri; Suzanne LePage; Paul P. Mathisen

Planning Four courses offered within WPI’s CEE undergraduate program present analyses thatprofessionals would be hard pressed to conduct without the use of GIS. These include: CE 3070“Urban and Environmental Planning”, CE 3074 “Environmental Analysis”, CE 4061“Hydrology” and CE 4071 “Land Use Development and Controls”. WPI’s undergraduatecourses are offered in seven-week terms per academic year, with students enrolling in 3 coursesin each term. The time constraints in the rigorous schedule further complicate the ability toutilize and teach software within the existing curriculum. Consequently, an integrated approachwas used to incorporate GIS into all of these courses. Technical considerations included the timerequired to obtain (clip) data

Conference Session

Faculty & Program Exchanges: Internationalizing, Collaborations, Interactions

Collection

2010 Annual Conference & Exposition

Authors

Vinod Lohani, Virginia Tech; Ricky Castles, Virginia Tech; Gary Riggins, Virginia Tech

Tagged Divisions

International

AC 2010-2064: A WORKSHOP FOR INDIAN ENGINEERING FACULTY UNDERTHE INDO-US COLLABORATION IN ENGINEERING EDUCATIONVinod Lohani, Virginia Tech Vinod K Lohani is an associate professor in the Engineering Education Department (EngE) and an adjunct faculty in the Civil and Environmental Engineering at Virginia Tech. He received a PhD in civil engineering from Virginia Tech in 1995. His research interests are in the areas of knowledge modeling, water and energy sustainability, engineering learning modules for freshmen, and international collaboration. He led a major curriculum reform project (2004-09), funded under the department-level reform program of the NSF, at Virginia Tech. A spiral curriculum

Conference Session

Collaborative Projects in Architectural Engineering Education

Collection

2010 Annual Conference & Exposition

Authors

Jill Nelson, California Polytechnic State University; Brent Nuttall, California Polytechnic State University; Allen Estes, California Polytechnic State University

Tagged Divisions

Architectural

previous efforts included:CM 431 Integrated Project Services: This three unit lab-based course provides an overview ofproject delivery methods with an emphasis on trends in integrated services project delivery. CMand ARCH students used a real project to integrate planning, design and construction efforts toachieve maximum project quality and value. The course enrolls up to 50 students.ARCE 460 Collaborative Design Laboratory: The course offered to ARCH and ARCEstudents investigated the collaborative nature of the design process as it relates to the structuralengineer and architect. This course enrolled up to 16 students.EDES 406 Sustainable Environments / EDES 408 Implementing Sustainable PrinciplesThe sequence covers two quarters and represents a

Conference Session

Including Engineering Economy in All Curricula

Collection

2010 Annual Conference & Exposition

Authors

Leland Blank, Texas A&M University

Tagged Divisions

Engineering Economy

technology be used to infuse engineering economics into curricula and courses? ≠ How can engineering economy topics be integrated into existing courses in any BS-level engineering curriculum? ≠ When is a separate course in engineering economy justified?The panel is comprised of individuals with varied backgrounds and different engineeringdisciplines, who come to the discussion with significantly different views of the need andformat of engineering economics in engineering curricula. The panel members include:Dr. Dave Holger ABET, President 2009-2010 Iowa State University: Associate Provost for Academic Affairs Dean, Graduate College

Conference Session

Exemplary Outreach Programs

Collection

2010 Annual Conference & Exposition

Authors

Lisa Pruitt, University of California, Berkeley; Eli Patten, University of California at Berkeley; Sara Atwood, University of California, Berkeley

Tagged Divisions

K-12 & Pre-College Engineering

technologies they see in everyday life yetthey may not have contact with adults who have the expertise to entertain their questions or theirlearning styles may be in conflict with traditional curriculum formats. For these children, anoutreach program can offer exposure to engineering skills such as analysis, development,building and testing through hands-on activities.1 The benefit of using undergraduates to developand implement engineering exhibits that addresses all facets of learning is that childrenexperience engineering in an interactive environment that is accessible regardless of learningstyle. Moreover, exposure to young, diverse role models reinforces the notion that engineering isa career path that is accessible to people regardless of

Conference Session

NSF Grantees Poster Session

Collection

2010 Annual Conference & Exposition

Authors

Lisa Schneider, Cornell University; Maria Terrell, Cornell University Math Dept.

university to enhance engineering students’ abilities to transfer and apply mathematicsto solve problems in engineering contexts. A recent curriculum innovation resulting from theseefforts involves the integration of collaborative, applied, problem-solving workshops into thefirst-semester engineering mathematics course. This paper will summarize the project team'swork to develop two instruments - one to gauge students’ abilities in using mathematics inengineering contexts; and the other to gauge students' self-efficacy perceptions related tostudying engineering and to learning and applying mathematics – that can be used to assess theeffects of this innovation and others like it. The paper will report on the processes being used todevelop and adapt

Conference Session

Faculty Set the Preliminary Standards for Co-ops

Collection

2010 Annual Conference & Exposition

Authors

Anthony Joseph, Pace University; Mabel Payne, Consultant

Tagged Divisions

Cooperative & Experiential Education

purpose of integrating theory with practice, students derivedmany other advantages3, 4, 12, 14, 15, 18, 25, 33, 37 from participating in cooperative educationprograms, which may be optional in some of the academic institutions where they are offered.Some of these advantages include the development of social skills, engagement in teamwork,improvement of communication skills, enhancement and greater clarity of future career goals,salary advantage, and the development of practical skills.An Interpretation of Work Based Learning in the Context of InterdisciplinarityA curriculum inclusive of a cooperative education strategy could be interpreted as aninterdisciplinary program5, 26, 31 where the work place learning experience is conceptually viewedas

Conference Session

Enhancing Recruitment and Retention in Engineering

Collection

2010 Annual Conference & Exposition

Authors

Beth McGinnis-Cavanaugh, Springfield Technical Community College; Glenn Ellis, Smith College; Diana Fiumefreddo, Smith College

Tagged Divisions

K-12 & Pre-College Engineering

and sharing curricula for their own classrooms.The workshop was designed as a learner-centered program to promote deep and meaningfullearning within the chosen Technology/Engineering curriculum strands with the followingsignificant core beliefs as a foundation: ≠ SPS teachers are experts in their classrooms ≠ The experiences and challenges of SPS teachers are valuable and important and must be validated and appreciated ≠ Workshop instructors have expertise in the subject matter, but do not have knowledge of the challenges of an SPS middle school classroom ≠ The workshop was a collaboration, not a top-down teaching experience ≠ Learning how teachers learn and teach is a