An intelligent fixture with a dynamic clamping scheme

Both proper fixture design and optimum fixturing execution are crucial to workpiece quality assurance in manufacturing. This paper deals with an integrated approach to fixturing problems and, in particular, a ‘live’ fixture with sensory feedback and on-line fixturing control strategy to perform an optimal fixturing operation. The framework of an integrated fixture design procedure is first presented. The functions and structure of an intelligent fixture are proposed. The prototype intelligent fixture with dynamic clamps capable of delivering accurate but varying clamping intensity is developed. This novel set-up has been proven to be effective for workpiece quality improvement and productivity enhancement through machining experiments on thin-walled workpieces.

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Respirometry for determination of the influents SS-concentration

Water Science & Technology ◽

10.2166/wst.1996.0031 ◽

1996 ◽

Vol 33 (1) ◽

pp. 311-323 ◽

Cited By ~ 2

Author(s):

A. Witteborg ◽

A. van der Last ◽

R. Hamming ◽

I. Hemmers

Keyword(s):

Experimental Design ◽

Activated Sludge ◽

Substrate Concentration ◽

Full Scale ◽

Activated Sludge Process ◽

Respiration Rates ◽

On Line ◽

Large Measurement ◽

Set Up

A method is presented for determining influent readily biodegradable substrate concentration (SS). The method is based on three different respiration rates, which can be measured with a continuous respiration meter which is operated in a cyclic way. Within the respiration meter nitrification is inhibited through the addition of ATU. Simulations were used to develop the respirometry set-up and decide upon the experimental design. The method was tested as part of a large measurement programme executed at a full-scale plant. The proposed respirometry set-up has been shown to be suitable for a semi-on-line determination of an influent SS which is fully based on the IAWQ #1 vision of the activated sludge process. The YH and the KS play a major role in the principle, and should be measured directly from the process.

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14C AMS at Suerc: Improving QA Data with the 5MV Tandem and 250KV SSAMS

Radiocarbon ◽

10.1017/s003382220004529x ◽

2010 ◽

Vol 52 (2) ◽

pp. 263-271 ◽

Cited By ~ 27

Author(s):

P Naysmith ◽

G T Cook ◽

S P H T Freeman ◽

E M Scott ◽

R Anderson ◽

...

Keyword(s):

Quality Assurance ◽

Sample Preparation ◽

Mass Spectrometer ◽

Random Access ◽

Capacity Measurement ◽

Tandem Accelerator ◽

Standard Data ◽

Accelerator Mass Spectrometer ◽

On Line ◽

Automated Data Acquisition

In 2003, a National Electrostatics Corporation (NEC) 5MV tandem accelerator mass spectrometer was installed at SUERC, providing the radiocarbon laboratory with 14C measurements to 4–5‰ repeatability. In 2007, a 250kV single-stage accelerator mass spectrometer (SSAMS) was added to provide additional 14C capability and is now the preferred system for 14C analysis. Changes to the technology and to our operations are evident in our copious quality assurance data: typically, we now use the 134-position MC-SNICS source, which is filled to capacity. Measurement of standards shows that spectrometer running without the complication of on-line δ13C evaluation is a good operational compromise. Currently, 3‰ 14C/13C measurements are routinely achieved for samples up to nearly 3 half-lives old by consistent sample preparation and an automated data acquisition algorithm with sample random access for measurement repeats. Background and known-age standard data are presented for the period 2003–2008 for the 5MV system and 2007–2008 for the SSAMS, to demonstrate the improvements in data quality.

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WWW.TELD.NET: Online Courseware Engine for Teaching by Examples and Learning by Doing

Journal of Educational Technology Systems ◽

10.2190/60jh-hhnh-62g3-qh9r ◽

2001 ◽

Vol 29 (3) ◽

pp. 219-235 ◽

Cited By ~ 1

Author(s):

G. Q. Huang ◽

B. Shen ◽

K. L. Mak

Keyword(s):

Teaching And Learning ◽

Virtual Classroom ◽

Learning By Doing ◽

General Purpose ◽

Project Based Learning ◽

Course Materials ◽

Summative Assessments ◽

On Line ◽

Set Up ◽

Electronic Delivery

TELD stands for “Teaching by Examples and Learning by Doing.” It is an on-line courseware engine over the World Wide Web. There are four folds of meanings in TELD. First, TELD represents a teaching and learning method that unifies a number of contemporary methods such as Problem-Based Learning (PBL) in medical education, Project-Based Learning (PBL) in engineering education, and Case Method (CM) in business education. Second, TELD serves as a Web server for hosting teaching and learning materials especially based on the TELD method. A variety of on-line facilities are provided for editing and uploading course materials such as syllabus, schedule, curriculum, examples of case study, exercises of mini-project, formative and summative assessments, etc. Third, TELD is a courseware search engine where educators are able to register their course materials and search for materials suitable for a particular course. In contrast with general-purpose search engines, TELD is set up for the special purpose of education. Therefore, the time and efforts spent on surfing are expected to be reduced dramatically. Finally, TELD is an on-line virtual classroom for electronic delivery of electronic curriculum materials. In addition to providing the lecture notes, TELD not only provides discussion questions for conducting in-class discussions and homework as formative assessment but also provides facilities for students to plan and submit their group work. This article presents an overview of the TELD courseware engine together with its background and underlying philosophy.

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Operational storm surge forecasting in the Netherlands: developments in the last decade

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2005.1578 ◽

2005 ◽

Vol 363 (1831) ◽

pp. 1441-1453 ◽

Cited By ~ 56

Author(s):

Martin Verlaan ◽

Annette Zijderveld ◽

Hans de Vries ◽

Jan Kroos

Keyword(s):

Quality Assurance ◽

The Netherlands ◽

Kalman Filtering ◽

Model Calibration ◽

Storm Surges ◽

Operational Environment ◽

Hydrodynamic Models ◽

Future Developments ◽

Set Up ◽

Storm Surge Forecasting

The accurate forecasting of storm surges is an important issue in the Netherlands. With the emergence of the first numerical hydrodynamic models for surge forecasting at the beginning of the 1980s, new demands and possibilities were raised. This article describes the main phases of the development and the present operational set-up of the Dutch continental shelf model, which is the main hydrodynamic model for storm surges in the Netherlands. It includes a brief discussion of applied data-assimilation techniques, such as Kalman filtering, the model calibration process and some thoughts on quality assurance in an operational environment. After further describing some select recent investigations, the paper concludes with some remarks on future developments in a European context.

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NEURAL MODELING AND CONTROL OF DYNAMIC SYSTEMS WITH HYSTERESIS

Transactions of the Canadian Society for Mechanical Engineering ◽

10.1139/tcsme-2007-0008 ◽

2007 ◽

Vol 31 (1) ◽

pp. 127-141

Author(s):

Yonghong Tan ◽

Xinlong Zhao

Keyword(s):

Dynamic Systems ◽

Control Strategy ◽

Neural Modeling ◽

Modeling And Control ◽

Control Scheme ◽

The Neural Networks ◽

Adaptive Control Strategy ◽

Set Up ◽

Modeling Strategy ◽

And Control

A hysteretic operator is proposed to set up an expanded input space so as to transform the multi-valued mapping of hysteresis to a one-to-one mapping so that the neural networks can be applied to model of the behavior of hysteresis. Based on the proposed neural modeling strategy for hysteresis, a pseudo control scheme is developed to handle the control of nonlinear dynamic systems with hysteresis. A neural estimator is constructed to predict the system residual so that it avoids constructing the inverse model of hysteresis. Thus, the control strategy can be used for the case where the output of hysteresis is unmeasurable directly. Then, the corresponding adaptive control strategy is presented. The application of the novel modeling approach to hysteresis in a piezoelectric actuator is illustrated. Then a numerical example of using the proposed control strategy for a nonlinear system with hysteresis is presented.

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