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Physical And Chemical Characteristics Of Commercially Available Brake Shoe Lining Materials: A Comparative Study Nov 2004

Physical And Chemical Characteristics Of Commercially Available Brake Shoe Lining Materials: A Comparative Study

A.S. Md Abdul Haseeb

The physical and chemical characteristics of four commercial automotive brake shoe lining materials used in heavy vehicles have been investigated and compared. Relevant physical properties viz. density, water absorption and swelling characteristics were determined using standard test methods. X-ray diffraction, infrared spectroscopy and optical microscopic techniques were used to identify the constituents. It has been observed that all of the four friction materials contain phenol formaldehyde resin as the matrix. Other major ingredients were also the same in all the samples but their amount and size varied. These include asbestos as fibre reinforcement, barium sulphate as filler and brass particles …


Physical And Chemical Characteristics Of Commercially Available Brake Shoe Lining Materials: A Comparative Study Nov 2004

Physical And Chemical Characteristics Of Commercially Available Brake Shoe Lining Materials: A Comparative Study

A.S. Md Abdul Haseeb

The physical and chemical characteristics of four commercial automotive brake shoe lining materials used in heavy vehicles have been investigated and compared. Relevant physical properties viz. density, water absorption and swelling characteristics were determined using standard test methods. X-ray diffraction, infrared spectroscopy and optical microscopic techniques were used to identify the constituents. It has been observed that all of the four friction materials contain phenol formaldehyde resin as the matrix. Other major ingredients were also the same in all the samples but their amount and size varied. These include asbestos as fibre reinforcement, barium sulphate as filler and brass particles …


Day 3: Friday, August 6, 2004: Cbm And Unconventional Gas Development, Gary Bryner, Ken Wonstolen Aug 2004

Day 3: Friday, August 6, 2004: Cbm And Unconventional Gas Development, Gary Bryner, Ken Wonstolen

Energy Field Tour 2004 (August 4-6)

19 pages (includes illustrations and maps).


Agenda: Energy Field Tour 2004, University Of Colorado Boulder. Natural Resources Law Center Aug 2004

Agenda: Energy Field Tour 2004, University Of Colorado Boulder. Natural Resources Law Center

Energy Field Tour 2004 (August 4-6)

Tour (day trips along the Front Range, originating in Boulder) held August 4-6, 2004.

Summary: Assorted articles, maps, brochures, and other materials prepared for participants of the tour

Contents:

2004 energy field tour agenda -- Mission and vision of the Natural Resources Law Center -- Natural Resources Law Center, University of Colorado School of Law : a brief introduction -- Boulder area street map 4 -- Chatauqua area map -- [Bus] Route 203/225 : Boulder/Lafayette/Baseline -- Boulder-Lafayette via Baseline [bus schedules]

WEDNESDAY, AUGUST 4, 2004: OIL & GAS PRODUCTION FACILITIES AND PLATTEVILLE GAS PROCESSING FACILITY: 'Our next shortage', The Washington …


Comparison Of Water And Saltwater Movement In Mortar Based On A Semiempirical Electromagnetic Model, Shanup Peer, R. Zoughi Aug 2004

Comparison Of Water And Saltwater Movement In Mortar Based On A Semiempirical Electromagnetic Model, Shanup Peer, R. Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

The presence of chloride ions in steel-reinforced structures leads to the corrosion of the reinforcement thus compromising the integrity and strength of the structure. Thus, it is of great interest to nondestructively detect and evaluate free chloride content in concrete. To this end, an investigation was initiated where two mortar cubes were soaked in distilled water and saltwater solutions, respectively. Their temporal microwave reflection properties were measured using open-ended rectangular waveguides on a daily basis for three cycles, each lasting 35 days. Subsequently, a semiempirical electromagnetic model was developed to simulate the reflection properties of the cubes. The outcome of …


Assessing The Quality Of Seawinds Rain Measurements, David G. Long, David W. Draper Jul 2004

Assessing The Quality Of Seawinds Rain Measurements, David G. Long, David W. Draper

Faculty Publications

While SeaWinds was designed to measure ocean winds, it can also measure rain over the ocean. SeaWinds on QuikSCAT active measurements of integrated columnar rain rate obtained via simultaneous wind/rain retrieval are evaluated via Monte Carlo simulation and the Cramer-Rao lower bound on estimate accuracy. Although sufficiently accurate in many conditions, the simultaneous wind/rain retrieval method used with SeaWinds on QuikSCAT data is ill-conditioned for certain wind directions and measurement geometries, sometimes yielding spurious rain rates in zero-rain conditions. To assess the validity of SeaWinds-derived rain rates, a simple empirically based rain thresholding scheme is presented, derived from simulated data. …


Automatic Detection And Validity Of The Sea-Ice Edge: An Application Of Enhanced-Resolution Quikscat/Seawinds Data, David G. Long, Jorg Haarpaintner, Rasmus T. Tonboe, Michael L. Van Woert Jul 2004

Automatic Detection And Validity Of The Sea-Ice Edge: An Application Of Enhanced-Resolution Quikscat/Seawinds Data, David G. Long, Jorg Haarpaintner, Rasmus T. Tonboe, Michael L. Van Woert

Faculty Publications

Sea-ice edge detection is an essential task at the different national ice services to secure navigation in ice-covered seas. Comparison between the Remund and Long ice mask image from enhanced-resolution QuikScat/SeaWinds (QS) products and the analyzed ice edge from high-resolution RADARSAT synthetic aperture radar has shown that the automatically determined QS ice mask underestimates the Arctic ice extent. QS data was statistically analyzed by colocating the data with ice charts around Greenland and with the National Aeronautics and Space Administration Team's Special Sensor Microwave/Imager (SSM/I) ice concentration algorithm over the whole Arctic region. All variables, i.e., the backscatter in vertical …


Simultaneous Wind And Rain Retrieval Using Seawinds Data, David G. Long, David W. Draper Jul 2004

Simultaneous Wind And Rain Retrieval Using Seawinds Data, David G. Long, David W. Draper

Faculty Publications

The SeaWinds scatterometers onboard the QuikSCAT and the Advanced Earth Observing Satellite 2 measure ocean winds on a global scale via the relationship between the normalized radar backscattering cross section of the ocean and the vector wind. The current wind retrieval method ignores scattering and attenuation of ocean rain, which alter backscatter measurements and corrupt retrieved winds. Using a simple rain backscatter and attenuation model, two methods of improving wind estimation in the presence of rain are evaluated. First, if no suitable prior knowledge of the rain rate is available, a maximum-likelihood estimation technique is used to simultaneously retrieve the …


Genetic Algorithm-Based Model For Determination Of Efficient Management Strategies For Irrigation Canal Networks, Talaat Taher El Gamel Jul 2004

Genetic Algorithm-Based Model For Determination Of Efficient Management Strategies For Irrigation Canal Networks, Talaat Taher El Gamel

Civil & Environmental Engineering Theses & Dissertations

An optimization model for the determination of efficient management strategies for an irrigation canal network is developed. The objective is to minimize the total water consumed while satisfying various system constraints. An unsteady flow model is used to simulate the flow in the network. A genetic algorithm- (GA-) based framework is used to solve the model. The suitable GA parameters that should be used within the model, as well as the performance of various constraint-handling techniques, are studied. Uncertainties in crop pattern and water consumption rates are incorporated into the search procedure to identify more reliable solutions. A graphical interface …


Drying Of Water Treatment Plant Residuals, Ali Mohammad Gharaibeh, Muttucumaru Sivakumar, Hagare Dharmappa Jan 2004

Drying Of Water Treatment Plant Residuals, Ali Mohammad Gharaibeh, Muttucumaru Sivakumar, Hagare Dharmappa

Faculty of Engineering - Papers (Archive)

Drying of ferric chloride water treatment plant residuals have been studied in two experimental sand drying beds. One bed was open and the other was covered with glass to study respectively the open bed drying of residuals under normal weather conditions and passive solar energy drying. The covered bed was fabricated, with a view, to simulate the solar distillation stills. A weather station was used to monitor the dynamic weather conditions in order to study their effect on the drying process. Solids content, drainage water volumes and distillate from the covered bed were measured on a daily basis. The aim …


World Water Crisis Looms, Luke Scott, Muttucumaru Sivakumar, Dharmappa Hagare Jan 2004

World Water Crisis Looms, Luke Scott, Muttucumaru Sivakumar, Dharmappa Hagare

Faculty of Engineering - Papers (Archive)

An investigation was undertaken to develop a robust solar water purification system for remote areas that have neither suitable potable water nor energy supplies. A study of the challenges of global water supply and existing treatment methods was made to aid the development of the design. Current world water resources are examined regarding climate change, population growth and irrigation and the likely effects are assessed for human health and mortality, potential for conflict, economics and effect on ecosystems. Solutions are posed in the form of development goals, wastewater reuse and desalination. Objectives for the design of effective desalination systems are …


A General Review Of Applications Of Artificial Neural Network To Water Industry, Xin Mi, Muttucumaru Sivakumar Jan 2004

A General Review Of Applications Of Artificial Neural Network To Water Industry, Xin Mi, Muttucumaru Sivakumar

Faculty of Engineering - Papers (Archive)

This paper presents case studies of applications of artificial neural network (ANN) to water industry including water treatment, water quality and water consumption. Overall, ANN was found to be superior to time series and multiple regression analysis for most applications. At the same time, however, ANN is a data driven model, so care has to be taken in preparing data for ANN models. Limitations of the current ANN study to coagulant dosages in water treatment plants are presented and further ANN improvements in this field are in progress.


Electrical Breakdown In Polar Liquids, Shu Xiao Jan 2004

Electrical Breakdown In Polar Liquids, Shu Xiao

Electrical & Computer Engineering Theses & Dissertations

Hydrodynamic processes following the electrical breakdown in polar liquids, mainly water and propylene carbonate, are studied with electrical pulse-probe systems and optical diagnostics including shadowgraphy and Schlieren techniques. The dielectric strength of water in a repetitively pulsed power system is found to be 750 kV/cm and 650 kV/cm for pulses of 200 nanosecond and 8 microsecond duration, respectively. For energies less than 1 J, the discharge plasma decays in approximately one microsecond. The mechanical effect created by the expanding plasma is a shock wave which has an initial pressure of 1 GPa and decays within approximately 5 microseconds. The observed …