Seminars, Training Programs and
Conferences @ AIT
SCE SEMINAR: Measuring Permeability, Young's Modulus, and Stress Relaxation by the Beam-Bending Technique?
The seminar will be conducted by Dr. Wilasa Vichit-Vadakan on Tuesday, 19 February 2002 at 10:30 a.m. in Room E220 (East-West Academic Building) She is currently associated with the Council of Science and Technology, Princeton University, New Jersey, USA, as a Teaching Fellow. Dr. Wilasa obtained her B.Sc. from the School of Civil and Environmental Engineering, Cornell University in 1995. She has two Master degrees: M.Sc. from the Dept. of Civil and Environmental Engineering, MIT in 1997, and M.A from the Dept. of Civil Engineering and Operation Research, Princeton University in 1999. She passed her Doctoral defense in January 2002 with a research on 'Beam-Bending Method for Permeability and Creep Characterization of Cement Paste' at the Dept. of Civil and Environmental Engineering, Princeton University. She is a recipient of several awards in teaching and research during her study. These include the Engineering Council Excellence in Teaching Award (1998), Graduate Student Gold Award (2000), and Friends of the International Center Excellence in Teaching Award (2001).
ABSTRACT:
Recent interest in the permeability of cement paste, mortars, and concrete lies in the need to gain further understanding of mechanisms affecting the durability of these materials. Conventional techniques for measuring permeability are cumbersome and often take days to complete just one measurement. This thesis proposes a new technique for measuring permeability. The advantage of this technique is that the results are obtained within a few minutes to a few hours; moreover, there is no problem with leaks or need for high pressures. The method is particularly well suited for examining changes in permeability and viscoelastic properties of young cement paste samples.
When a saturated rod of a porous material is instantaneously deflected under three-point bending, two types of relaxation processes occur simultaneously: hydrodynamic relaxation, caused by the flow of liquid in the porous body to restore ambient pressure, and viscoelastic relaxation of the solid network. By measuring the decrease in the force required to sustain a constant deflection, it is possible to obtain the permeability and Young's modulus from the hydrodynamic relaxation function, in addition to the stress relaxation function of the sample. The exact viscoelastic solution is developed and the total relaxation is shown to be very closely approximated as the product of the hydrodynamic and stress relaxation functions.
The analytical results are verified on porous Vycor glass saturated in various solvents, including normal alcohols, water, and glycerol. The results show excellent agreement with the theory. Consistent with observations of previous workers, the permeability is found to be influenced by the size of the solvent molecule; by assuming that the pore surfaces are covered with a monolayer of immobile solvent, the observed variation can be explained.
The evolution of the permeability, Young's modulus, and stress relaxation function are reported for Type III Portland cement paste with water-cement ratios ranging from 0.4 to 0.7 from the age of 1 day to 21days. The permeability and Young's modulus agree with the range reported by other workers. The stress relaxation function is shown to preserve its shape during aging; that function is numerically transformed into the creep function.
SEC students are requested to attend this seminar. Interested persons are welcome.
For further details, please call Mr. Djoen San at 524 6423.
ISE PRESENTATION ON LABVIEW
The Industrial Systems Engineering Program, School of Advanced Technologies will hold a LabVIEW presentation on Tuesday 19 February 2002 at 1.30-3.30 p.m., in room 115, Chalerm Prakiat Building,. The presentation will be conducted by Thanan Weangsang, Senior Engineer, Trinergy Instrument Co., Ltd.
ABSTRACT:
LabVIEW is a highly productive graphical programming language for building data acquisition and instrumentation systems. Its tight integration with measurement hardware facilitates rapid development of data acquisition, analysis and presentation solutions. LabVIEW contains powerful built-in measurement analysis and a graphical compiler for optimum performance.
SAT students are encouraged to attend. Interested persons are welcome.
SERD SEMINAR: PRECAUTIONARY PRINCIPLE - WHAT LEVEL OF PROOF IN ENVIRONMENTAL DECISION MAKING?
Prof. Poul Harremoes of the Department of Environmental Science and Engineering, Technical University of Denmark, will conduct this seminar on Thursday, 21 February at 2 p.m. at the Milton E. Bender Jr. Auditorium. Prof. Harremoes is a well-known authority in environmental management and a recipient of the prestigious 'Stockholm Water Prize', and more recently, the 'Heineken Prize'.
ABSTRACT :
According to established principles, an activity or an agent is assumed harmless until proven harmful. That is how international trade is regulated through WTO. The interpretation is that 'scientific proof' is needed to regulate an activity or agent. The question is whether such a stringent requirement is warranted in a situation where the public is exposed to the potential harm. The basic question is: Who carries the burden of the risk of being wrong? Presently, there is a conflict between USA and EU about import of beef with residual growth hormones to EU. The European Environment Agency published on 11 January 2002 a report on The Precautionary Principle. Prof. Harremoes, chairman of the editorial committee, will present the results.
The report is available on the EEA-webpage:
http://reports.eea.eu.int/environmental_issue_report_2001_22/en.
For reservations, please contact Khun Suchitra Piempimsest, Urban Environmental Engineering and Management Program, SERD, AIT, P.O. Box 4 Klong Luang, Pathumthani 12120. Fax: (66)-2524-5625. E-mail: suchitra@ait.ac.th
Computational Grids: New Challenges for Distributed Computing
The Computer Science and Information Management (CSIM) Program, School of Advanced Technologies
will be holding a special lecture on 8 March 2002, 1:00 p.m. in CS Room 209. The lecture entitled 'Computational Grids: New Challenges for Distributed Computing' will be conducted by Prof. Yakup Paker (e-mail: Paker@dcs.qmul.ac.uk, Department of Computer Science, Queen Mary, University of London.
ABSTRACT:
Clustering of a wide variety of geographically distributed resources, such as supercomputers, storage systems, data sources, special facilities, etc., as a unified resource has led to the concept of 'Computational Grids'. This is analogous to the electrical power grid that provides power to consumers by simple electrical connections, irrespective where the power generators are located or their type. The computational grid technology thus attempts to provide users transparent access to the entire set of resources connected. Thus the computational grid needs to cope with aspects such as authentication, name space, resource management, scheduling, accounting, etc. At the same time, a number of problems in modern distributed computing are being addressed under the area broadly referred as peer-to-peer computing. Under this heading a wide range of technologies are developed to increase the utilisation of information, bandwidth and computing resources in the Internet. This lecture investigates the type of problems posed by the computational grids and to what extend those overlap with or differ from the concerns of peer-to-peer distributed computing.