Impact of Embedded Carbon Fiber Heating Panel on the Structural/Mechanical Performance of Roadway Pavement

INE/AUTC 12.3

Digital Embedding System with Heater and Cooler

Embedding is an anatomical pathology laboratory device that is very important for producing quality slices and is also a device used to process paraffin tissue, so that the tissue can be cut with higher precision using a microtom (slicer). From the process of melting paraffin crystals using a manual heating process with bunsen flame heaters (fire heaters) so that the paraffin crystals can be transformed from the crystal into liquid. While paraffin crystals that have been processed from the crystal to liquid form are poured into the mold and left to freeze. In this case, an embedding system device will be made equipped with heating and cooling. The temperature used for the liquefaction process is 50C while the temperature for cooling is 17C. After making the process of making device, experiment device, and retrieving data, the error percentage results were 0.016% at the heating temperature and 0.08% at the coolant temperature, and the percentage of heating samples obtained in the sample was 61.3%, while the percentage samples for parts coolers get a value of 92

Testing of MEMS gyroscopes

Tato diplomová práce se zabývá teoretickými poznatky o konstrukcích a parametrech MEMS gyroskopů. Dále je prezentován navržený měřicí řetězec pro testování MEMS gyroskopů ve společnosti Honeywell International s.r.o. a to zejména s použitím systémů: Polytec MSA-500, goniometrických plošin a kontroléru od firmy Standa a kontroléru pro řízení Peltierových článků. Praktická část diplomové práce obsahuje popis navrženého kontroléru pro řízení teploty testovaného zařízení a také popis aplikace v prostředí LabVIEW („Measurement systém“), která se používá pro řízení pozice dvou goniometrických plošin a pro řízení Peltierových článků. Tento systém je schopen plně řídit pozici goniometrických plošin, zarovnat povrch testovaného zařízení do ideálně kolmé pozice vůči optické hlavě analyzátoru Polytec MSA-500 a také kontrolovat teplotu testovaného zařízení. Závěrečná část diplomové práce je věnována testům základních parametrů MEMS gyroskopů se zaměřením na závislost tzv. Angle Random Walk a offsetu MEMS gyroskopu na kvalitě vakua v prostředí struktury.This diploma thesis presents theoretical information regarding MEMS gyroscopes their parameters and designs. The description of measurement chain be used for testing of MEMS gyroscopes in Honeywell International s.r.o. is presented. Special focus is devoted to: the Polytec MSA-500 system, the Standa goniometers and their controller, Peltier cell and its driver. The practical part of this thesis contains the description of the thermal control system and also the description of the developed “Measurement system” in the LabVIEW software which is used for controlling the goniometers position and the Peltier cell. The system is able to fully control two goniometer stages, align the surface of tested MEMS device to orthogonal position with respect to the Polytec MSA-500 measurement head and also control the temperature of the tested device. The last part of this thesis presents the tests of the MEMS gyroscope parameters with special focus to the MEMS gyroscope angle random walk and the bias dependence on the vacuum quality of the structure environment.

A shape memory alloy adaptive tuned vibration absorber: design and implementation

In this paper a tuned vibration absorber (TVA) is realized using shape memory alloy (SMA) elements. The elastic modulus of SMA changes with temperature and this effect is exploited to develop a continuously tunable device.A TVA with beam elements is described, a simple two-degree-of-freedom model developed and the TVA characterized experimentally. The behaviour during continuous heating and cooling is examined and the TVA is seen to be continuously tunable. A change in the tuned frequency of 21.4% is observed between the cold, martensite, and hot, austenite, states. This corresponds to a change in the elastic modulus of about 47.5%, somewhat less than expected.The response time of the SMA TVA is long because of its thermal inertia. However, it is mechanically simple and has a reasonably good performance, despite the tuning parameters depending on the current in a strongly nonlinear way

Development of a control system for gas concentration and temperature in an animal preference chamber

An enhancement of the environmental control capabilities was planned and executed for an Environmental Preference Chamber (EPC) used for animal behavior testing. A fuzzy logic controller (FLC) was designed and built to control distinct ammonia concentration levels independently in each of the EPC’s four compartments. The FLC was written in MATLAB and utilized in tandem with custom software created in a visual-based programming language. The control software compared NH3 measurements from an infrared photo-acoustic gas analyzer to user-defined setpoints for each compartment, and input the difference to the FLC. The FLC computedan incremental change to the voltage signal used to adjust four Mass Flow Controllers, changing the volumetric flow rate of supplied NH3 to each compartment. Average (± standard deviation) NH3 concentrations were: 1.8 ± 0.8ppm, 10.2 ± 0.5ppm, 20.1 ± 0.8ppm, and 40.5 ± 1.3ppm for setpoint concentrations of 0, 10, 20, and 40ppm, in each of the four compartments, respectively. Approximately 90 minutes were required for all compartments to be within 5% of their setpoint concentration when starting from fresh air conditions. An expansion of the heating capacity of each compartment of the Environmental Preference Chamber was performed by increasing the installed heat capacity of in-line electrical resistance coils from 200W to 600W. The maximum temperature rise increased from 5.7±0.5°C to 15.1±0.6°C, with a time constant, τ, of 1.3±0.1 h. The 600W heating capacity achieved 95% of a 1°C and 3°C positive temperature step response in 12.3±2.3 min and 24.0±3.3 min, respectively. This was faster than the original 200W heating system, which achieved 95% of a 1°C and 3°C positive temperature step response in 18.0±2.8 min and 51.9±12.8 min, respectively. The setpoint overshoot of the new 600W heating system was 1.5±0.4°C and 0.9±0.1°C for 1°C and 3°C, respectively. This overshoot was greater than for the original 200W heating system, which showed a 0.4±0.1°C overshoot for the +1°C step response and a negligibly small overshoot for the 3°C. Cooling to room temperature was achieved using supply fans. First-order step response time constants, τ, for 1°C and 3°C negative step responses to ambient air temperature were 39.0±3.4 min and 26±1.4 min, respectively. The discrete On/Off temperature controller did not noticeably impact the performance of the fuzzy logic gas concentration controller when operating simultaneously. Four distinct ammoniated environments were created while the temperature controller was set to maximum temperature rise. The ammonia concentrations experienced minor perturbations during temperature rise, but the gas concentration controller quickly corrected these. The exhaust fan created noise in the Temp/Rh sensors, affecting the temperature control by dampening any oscillations when achieving a setpoint of 27°C (temperature increase of +5°C above ambient air temperature). No meaningful difference was observed in the gas concentration controller performance when simultaneously maintaining a temperature setpoint

An Approach to Optimal Control of the Combustion System in a Reverberatory Furnace

En este trabajo se presenta una técnica de control óptima aplicada al control del exceso de aire en el proceso de combustión de un horno reverbero mediante el monitoreo del porcentaje de O2 en la chimenea, el controlador es diseñado basado en un modelo no-lineal estimado con redes neuronales y se emplea para el previo entrenamiento una base de datos conformada por dos conjuntos: uno para entrenamiento y otro para la validación.In this work an optimal control technique is applied to control the excess air in the combustion process of a reverberatory furnace by the monitoring of O2 percentage in the stack, the controller is designed based on a nonlinear model estimated by artificial neural networks and a data base is used for the previous training; the data base has two subsets one for training and other to validate the net

Dilemma of mathematics

The pursuit of knowledge and the use of reason, based on sense and observation is a key ingredient for research. Mathematics is a creation of human mind concerned chiefly with ideas, processes and reasoning. In this paper, we will try to give a new comprehensive definition of mathematics to understand “what is mathematics”. We will discuss the controversial nature and position of mathematics and its scientific status. We will highlight the position of mathematics in different civilizations. We will highlight the mythical issues about Mathematics. We will also discuss the current state of mathematics i.e. mathematics in crises, especially pure mathematics and will put forward the remedial suggestions. We have gathered together some of these impressions; these are all tentative, nothing final about them, but these are here nonetheless

Development of an Ammonia Reduction After-Treatment Systems for Stoichiometric Natural Gas Engines

Three-way catalyst (TWC) equipped stoichiometric natural gas vehicles have proven to be an effective alternative fuel strategy that shows significant low NOx emissions characteristics. However, recent studies have shown the TWC activity to contribute to elevated levels of tailpipe ammonia (NH 3) emissions. Although a non-regulated pollutant, ammonia is a potent pre-cursor to ambient secondary PM formation. Ammonia is an inevitable byproduct of fuel rich operation that results in lowest NOx slip through the TWC after-treatment system.;The main objective of the study is to develop a passive Ammonia Reduction Catalyst (passive-ARC) based NH3 reduction strategy that results in an overall reduction of ammonia as well as NOx emissions. The study investigated the characteristics of Fe-based and Cu-based zeolites SCR catalysts in storage and desorption of ammonia at high exhaust temperature conditions, that are typical of stoichiometric natural gas engines. Continuous measurements of NOx and NH3 before and after the SCR systems were conducted using a Fourier Transform Infrared Spectrometry (FTIR) gas analyzer. Results of the investigation showed that both, the Fe- and Cu zeolite SCRs adsorbed above 90% of TWC generated NH3 emissions below 350--375 °C SCR temperatures. Desorption or slipping of NH3 was observed at exhaust gas temperatures exceeding 400 °C. In terms of NOx conversions, Fe-zeolite showed efficiency between 50--80% above temperatures of 300--350 °C while Cu-zeolite performed well at lower SCR temperature from 250 °C and above with a conversion efficiency of greater than 50%.;In order to efficiently reduce both NOx and NH3 simultaneously over longer durations it was found that an engine-based air fuel ratio operation strategy for the passive-ARC system must be developed. To this extent, the study extended its objectives to develop an engine-based control strategy that results in stoichiometric ammonia production operation followed by brief lean operation to regenerate the saturated ammonia reduction catalyst using high NOx slip through TWC. The study presents comprehensive results of ammonia storage characteristics of SCRs pertaining to stoichiometric natural gas engine exhaust as well as an advanced engine control strategy approach to simultaneously reduce both NOx and NH3 using an alternating air -fuel ratio approach

Industry/University Collaboration at the University of Michigan-Dearborn: A Focus on Relevant Technology

https://deepblue.lib.umich.edu/bitstream/2027.42/154105/1/kampfner1997.pd