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Dissertations / Theses on the topic 'Air Brakes'
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1
Coimbatore, Subramanian Shankar Ram. "A diagnostic system for air brakes in commercial vehicles." Texas A&M University, 2003. http://hdl.handle.net/1969.1/5857.
Full textAbstract:
This dissertation deals with the development of a model-based diagnostic system
for air brake systems that are widely used in commercial vehicles, such as trucks,
tractor-trailers, buses, etc. The performance of these brake systems is sensitive to
maintenance and hence they require frequent inspections. Current inspection techniques
require an inspector to go underneath a vehicle to check the brake system
for possible faults, such as leaks, worn brake pads, out-of-adjustment of push rods,
etc. Such inspections are time consuming, labor intensive and difficult to perform
on vehicles with a low ground clearance. In this context, the development of an onboard/
handheld diagnostic tool for air brakes would be of significant value. Such a
tool would automate the brake inspection process, thereby reducing the inspection
time and improving the safety of operation of commercial vehicles. In this dissertation,
diagnostic schemes are developed to automatically detect two important and
prevalent faults that can occur in air brake systems â leaks and out-of-adjustment of
push rods.
These diagnostic schemes are developed based on a nonlinear model for the pneumatic
subsystem of the air brake system that correlates the pressure transients in the
brake chamber with the supply pressure to the treadle valve and the displacement of the treadle valve plunger. These diagnostic schemes have been corroborated with
data obtained from the experimental facility at Texas A&M University and the results
are presented.
The response of the pneumatic subsystem of the air brake system is such that it
can be classified as what is known as a âÂÂSequential Hybrid SystemâÂÂ. In this dissertation,
the term âÂÂhybrid systemsâ is used to denote those systems whose mathematical
representation involves a finite set of governing ordinary differential equations corresponding
to a finite set of modes of operation. The problem of estimating the push
rod stroke is posed as a parameter estimation problem and a transition detection
problem involving the hybrid model of the pneumatic subsystem of the air brake system.
Also, parameter estimation schemes for a class of sequential hybrid systems are
developed. The efficacy of these schemes is illustrated with some examples.
2
Ramaratham, Srivatsan. "A mathematical model for air brake systems in the presence of leaks." Texas A&M University, 2008. http://hdl.handle.net/1969.1/86043.
Full textAbstract:
This thesis deals with the development of a mathematical model for an air brake
system in the presence of leaks. Brake systems in trucks are crucial for ensuring
the safety of vehicles and passengers on the roadways. Most trucks in the US are
equipped with S-cam drum brake systems and they are sensitive to maintenance.
Brake defects such as leaks are a major cause of accidents involving trucks. Leaks in
the air brake systems affect braking performance drastically by decreasing the peak
braking pressures attained and also increasing the time required to attain the same,
thereby resulting in longer stopping distances. Hence there is a need for detecting
leaks in an air brake system.
In this thesis, a mathematical model for an air brake system in the presence of
leaks is developed with a view towards developing an automatic leak detection system
in the near future. The model developed here builds on an earlier research at Texas
A&M University in which a "fault free" model of an air brake system is developed,
i.e., a mathematical model of an air brake system that predicts how the pressure in
the brake chamber evolves as a function of the brake pedal input when there are no
leaks in the air brake system.In order to develop a model for an air brake system in
the presence of leaks, one must characterize a "leak". A leak may be characterized by
the location and its size. Since the pipes are short, the location of the leak does not significantly affect the evolution in the brake pressure as much as its size. For this
reason, "effective area" of the leak was chosen as a characteristic of the leak. It was
estimated by fitting an empirical relation for leak with leak flow measurement data.
The supply pressure and effective area of leak comprised the inputs to the model
along with the displacement of the foot pedal (treadle valve plunger). The model was
corroborated with the experimental data collected using the setup at Texas A&M
University.
3
Bowlin, Christopher Leland. "A pressure control scheme for air brakes in commercial vehicles." Texas A&M University, 2005. http://hdl.handle.net/1969.1/4934.
Full textAbstract:
This research is focused on developing a control scheme for regulating the pressure in the
brake chamber of an air brake system found in most commercial vehicles like trucks,
tractor-trailers and buses. Such a control scheme can be used for providing the ground
work for future systems such as forward collision avoidance systems, advanced anti-lock
brake systems and differential braking systems. The development of this controller
involves two tasks. The first task was the development of a control scheme for achieving
the desired pressure in the brake chamber. This scheme was based on a mathematical
model of the treadle valve of the air brake system. The second task was the implementation
of this control scheme on the experimental facility that was set up at Texas A&M
University. The results indicate successful control of a desired brake chamber pressure for
a demonstrated range of controller gains.
4
Ripley, Ian, and ian ripley@qr com au. "An Investigation of Brake Application Delays in Australian Train Brake Systems." Central Queensland University. Engineering, 2005. http://library-resources.cqu.edu.au./thesis/adt-QCQU/public/adt-QCQU20060720.100110.
Full textAbstract:
An investigation of brake application delays in Australian train brake systems
began with a literature review of pneumatic train braking systems. Data located in the
review gave examples of brake application delays of pre 1990 designs from the U.K.,
India and North America. Information on application delays on later Australian designs
was scarce. Reading of literature has shown a difference between the Australian and
North American control valves in the way the propagation of the pressure reduction rate
in the brake pipe is maintained. Control valves of the North American style allow the
brake pipe air to be connected for a short time to a small cavity or quick service volume
of each valve. The quick service volume is then released to atmosphere. The action of
exhausting a small amount of air from the brake pipe helps to ensure a propagation of an
adequate pressure reduction rate as it travels to the next valve. Australian control valves
rely on the ratio of the volume of brake pipe between control valves and the size of the
quick service volume or bulb to ensure the propagation of an adequate pressure
reduction as it travels to the next valve. The air in a bulb of an Australian valve is not
expelled to atmosphere until a brake release is made.
The research explored possible reductions in application delays by utilizing an
experimental pipe test rack that included 4 control valves and 120 meters of brake pipe.
Experiments with different configurations of exhaust orifices or chokes, valves and
branch pipe lengths that supplied the valves gave a record acquired by data acquisition
of the timing of each valve and the local pressure drop from a valve or each valve for
comparison.
Experiments with exhaust chokes that gave a reduction drop rate in the brake pipe
that approached the minimum required to operate a control valve resulted in instability
of the application operation of the control valve. The quick service volume of different
sizes was included in the experiments to give comparisons in the propagation of the
pressure reduction toward the end of a long train. Further increases into the size of the
bulb of a control valve to enhance the propagation features toward the end of a long
train are discussed. The branch pipe with different diameters from 12 mm to 20 mm and
lengths from 160 mm to 800 mm when fitted to an adaptor pipe bracket were
investigated and results show that larger diameters gave larger gulps in the brake pipe.
Other components that were studied included the pipe bracket that is fitted on some
control valves. The pipe bracket and isolation cock was found to add 282 mm of
additional length to the air path and while not changing the operation of the valve, the
results showed a smaller drop in local pressure in the brake pipe to assist the pressure
reduction rate than shown in valves without pipe brackets.
5
Stonawski, Ondrej. "NON-DESTRUCTIVE EVALUATION OF CARBON/CARBON BRAKES USING AIR-COUPLED ULTRASONIC INSPECTION SYSTEMS." Available to subscribers only, 2008. http://proquest.umi.com/pqdweb?did=1674101471&sid=2&Fmt=2&clientId=1509&RQT=309&VName=PQD.
Full textAbstract:
Thesis (M.S.)--Southern Illinois University Carbondale, 2008."Department of Mechanical Engineering and Energy Processes." Keywords: Air-coupled ultrasonic, Carbon/carbon brakes, Nondestructive evaluation. Includes bibliographical references (p. 114-115). Also available online.
6
Schick, Bastian. "A Digital Test Bench for Pneumatic Brakes." Thesis, KTH, Spårfordon, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-290043.
Full textAbstract:
This master’s thesis covers the structuring and implementation of a digital testbench for the air brake system of freight trains. The test bench will serveto further improve the existing brake models at Transrail Sweden AB. Theseare used for the optimised calculation of train speed profiles by the DriverAdvisory System CATO. This work is based on the research of the technicalbackground, as well as the methodical approach to physical modelling anda modular implementation of the test bench. It gives full flexibility for thesimulation of customised train configurations using the European UIC brakesystem. Train length and vehicle arrangement can be adapted to the user’sspecific needs. For example, the test bench could be used for the simulation ofa train with distributed power. The system parameters are stored in a vehiclelibrary for the convenient generation of train configurations. This vehiclelibrary is freely expandable.The simulation is based on an equivalent electric circuit model which iscompleted with nozzle flow modelling. This model involves monitoring themain pipe, brake cylinder and reservoir pressure. Linear approximation is usedto obtain braking forces for the individual wagons and for the whole train. Thedepiction of the brake system behaviour is mostly accurate in the operationalscenarios, which is validated with measurement data. Additional calibrationis required for further reduction of the simulation errors and an extension ofthe model’s domain of validity. The test bench is developed by incrementaland iterative modelling and prepared for further improvements and variations,for example the adaption to the American AAR system variant.The presented work can also be used as a basis for similar implementationssuch as driving simulators. The methods are transferable to other applicationsof modular simulation.Det här examensarbetet omfattar formgivningen och implementeringen aven digital provbänk för tyckluftsbromssystemet på godståg. Provbänken skaanvändas för att vidareutveckla befintliga bromsmodeller hos Transrail SwedenAB. De används för beräkningen av optimerade hastighetsprofiler förtåg i förarassistanssystemet CATO. Arbetet baserar sig på undersökningenav den tekniska bakgrunden, samt ett metodiskt angreppssätt för fysikaliskmodellering. Verktyget är implementerat på ett modulärt sätt. Provbänkenger full flexibilitet för simuleringen av skräddarsydda tågkonfigurationer somanvänder det europeiska UIC-bromssystemet. Tåglängd och fordonsanordningkan anpassas enligt användarens behov, till exempel för simulering av fördeladtraktion. Systemparametrarna lagras i ett fordonsbiliotek som förenklar inmatningenav tågkonfigurationer. Fordonsbiblioteket kan utvidgas enligt behov.Simuleringen är baserad på en ekvivalent strömkretsmodell, som kompletterasmed modellerad dysströmning. Simuleringen beskriver trycket ihuvudledningen, bromscylindern och förrådsluftsbehållaren. Bromskrafternaapproximeras linjärt efter trycken för de enskilda vagnarna såväl som helatåget. Simuleringen återger beteendet av bromssystemet i alla driftsituationerpå ett verklighetsnära sätt, enligt validering med mätdata från Knorr-Bremse:stestanläggning. Ytterligare kalibrering behövs för att minimera avvikelserna isimuleringen och för att utvidga modellens giltighetsdomän. Provbänken harutvecklats i stegvis modellering och är väl förberedd för vidareutveckling ochanpassning. Ett exempel är anpassningen för att simulera det amerikanskaAAR-bromssystemet.Arbetet som presenteras här är lämplig för användning i liknande applikationer,såsom körsimulatorer. Metoden kan tillämpas allmänt på övrigaanvändningsområden av modulär simulering.
7
Lang, Allan M. "An investigation into heavy vehicle drum brake squeal." Thesis, Loughborough University, 1994. https://dspace.lboro.ac.uk/2134/7447.
Full textAbstract:
Many mechanisms have been suggested for brake squeal over many years. In order to identify the most appropriate of these mechanisms, an experimental investigation has been carried out to define in detail the vibration characteristics of a squealing heavy vehicle air operated drum brake on both a vehicle and a laboratory brake test rig. This required the development of a novel 'scanning' technique for the modal analysis of the rotating drum, which showed the presence of well-defined complex wavelike modes. From these results, the dynamic behaviour of the drum, in particular, is found to be in good qualitative agreement with the predictions of a simple 'binary flutter' mechanism of squeal. Based on the role of rotor symmetry in this mechanism, a means of decoupling, flutter modes is developed involving a reduction in the rotational symmetry of the drum by means of attaching masses in a defined pattern at its periphery. It is shown theoretically that such decoupling would be expected to increase the dynamic stability of the brake, and experimental application of the technique confirms its effectiveness in reducing or eliminating squeal. Practical design aspects of reducing the rotational symmetry of the drum are considered, using finite element modelling, and it is also shown that the technique can be effective in other types of vehicle brake, such as disc brakes and hydraulic drum brakes. The simple lumped parameter models used in the above work are inadequate as brake design tools, however, and so a novel application of finite element modelling is used to extend the principle of the binary flutter mechanism to a more detailed model of a complete brake. This is shown to be capable of predicting known features of squeal and may be used as a brake design tool for both the brake structure and the friction material.
8
Oues, Adnan Khalil. "PROTECTION OPTIMIZATION OF CARBON-CARBON COMPOSITES AGAINST AIR OXIDATION BY COATING WITH ANTI-OXIDANTS." OpenSIUC, 2017. https://opensiuc.lib.siu.edu/dissertations/1376.
Full textAbstract:
AN ABSTRACT OF THE DISSERTATION OF TITLE: (OPTIMIZATION PROTECTION OF CARBOB-CARBON COMPOSITES DISC-BRAKES MATERIAL BY COATING WITH ANTI-OXIDANTS) Developing glass enhancer mixture solutions (Ki’s), which promote the formation of a stable glass layer, homogenous clear liquid solution, and low viscosity liquid form, are easy to apply, and penetrating. They are compatible with ceramic liquid glass based anti-oxidants for treating surfaces of carbon/carbon composites material, and significantly increase the rate of protection against oxidation. Ki’s’ are comprised of mixing chemical compositions at standard temperature and pressure conditions from group one and two such as Na, K, Ca, Mg, etc. of 5 to 25 wt. %, deionized water from 95 to 75 % by weight, and adding up to 1 % by weight of surfactants such as DF-16, DF-20, and CF-10 with specific proportions, and followed by thorough stirring to produce a homogeneous blend of mixture solution. The glass enhancers, which are aqueous mixture solutions, are applied to the surfaces of carbon/carbon (C/C) composites by dipping, brushing, spraying, or other painting application techniques, followed by annealing, or a heat-treating range of 80 to 110 ℃ for a minimum of 8 hours, and allowing cooling time of the coated C/C composites of a minimum of 12 hours to room temperature. Preferential compatibility of the glass enhancer mixture solutions (Ki's) is with liquid glass former's, anti-oxidants comprised mostly of borate and phosphate glasses. The glass enhancer solution mixtures (Ki’s) are supplemental additions to ceramics’ liquid anti-oxidants coatings used for carbon-carbon composites protection against oxidation, and it will increase the rate of protection against oxidation for low, and moderate temperature’s range from 400 to 900 ℃. The glass enhancer Ki’s mixture solutions should be used with liquid glass former's’ anti-oxidants, such as SiO₂, GeO₂, B₂O₃, and P₂O₅. A series of glass enhancer’s Ki’s, heat treatment cycle (char-cycle) ranged between 700 to 900 ℃, and application methods, were developed and tested experimentally. Two arbitrary isothermal temperatures of 650 ℃, and 871 ℃ were selected for thermal oxidation testing, and a temperature of 650 ℃ was selected, and tested against catalytic thermal oxidation. Additions of glass enhancer Ki’s improved protection of C/C composites disc-brakes against oxidation by double, and triple amount of time in hours versus the use of anti-oxidant coatings alone.
9
Mulchandani, Hiten. "An engine air-brake integration study." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/62880.
Full textAbstract:
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2011.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student submitted PDF version of thesis.
Includes bibliographical references (p. 109-112).
The feasibility of operating an engine air-brake (EAB) integrated with a pylon duct bifurcation in a realistic aircraft engine environment has been analyzed. The EAB uses variable exit guide vanes downstream of a high bypass ratio (BPR) fan rotor to produce drag quietly by swirling flow out of the fan nozzle. The swirling motion yields low pressure in the vortex core from simple radial equilibrium, thereby generating pressure drag. The 4-BB internal plug and 5-BB external plug nozzles of BPR 8 are chosen to provide a realistic environment for model-scale tests at the NASA Aero-Acoustic Propulsion Lab (AAPL). The objectives of this study are to quantify the impact of a pylon on the drag and noise of an EAB, and explore means to mitigate the potential loss of swirling flow and associated drag. Analysis is conducted at approach conditions on the 4-BB nozzle, with fan and core nozzle pressure and temperature ratios obtained from an engine cycle analysis. A pylon is designed to represent engine installations typically encountered in short-range jet aircraft. The pylon is a prismatic NACA 0012 airfoil geometry with swept leading, trailing edges and an extended internal fairing to facilitate compatibility with both nozzles in the AAPL facility. The EAB cases analyzed include three types of pylon/vane configurations: (1) the baseline pylon with un-deflected swirl vanes is used in the calculation of the equivalent drag coefficient (CD); (2) the pylon with the trailing edge (TE) flap deflected full-span by 35 degrees is used to set structural load limits for detailed design of the baseline pylon; and (3) configurations with the pylon TE flap deflected partial-span by 20 degrees and asymmetric swirl vanes are used to generate swirling outflow from the fan nozzle exhaust. The partial-span deflection cases are further categorized by the location of the asymmetric vanes: at the nozzle exhaust (aft) and further upstream. Computational results demonstrate the aft vanes generate CD in the range 0.35-0.61 and the upstream vane cases produce CD between 0.09-0.18. The difference in drag is because the flow avoids the majority of the duct bifurcation in the aft vanes cases to produce stronger swirling outflow. A CD value between 0.7-1.0 is required to achieve a 3-4 degree glidescope change and therefore an overall noise benefit of 2.5 dB for a conventional tube-and-wing aircraft on approach. The aft vane configurations show promise in reaching this target while the upstream vane installation concepts require further investigation.
by Hiten Mulchandani.
S.M.
10
Senkal, Doruk. "Haptic surgical aid system with magnetorheological brakes for dental implants." Pullman, Wash. : Washington State University, 2009. http://www.dissertations.wsu.edu/Thesis/Fall2009/d_senkal_111509.pdf.
Full textAbstract:
Thesis (M.S. in mechanical engineering)--Washington State University, December 2009.Title from PDF title page (viewed on Jan. 4, 2010). "School of Engineering and Computer Science." Includes bibliographical references (p. 77-81).
11
Coimbatore, Subramanian Shankar. "Modeling the pneumatic subsystem of a S-cam air brake system." [College Station, Tex. : Texas A&M University, 2004. http://hdl.handle.net/1969.1/328.
Full textAbstract:
Thesis (M.S.)--Texas A&M University, 2003."Major Subject: Mechanical Engineering" Title from author supplied metadata (record created on Jul. 18, 2005.) Vita. Abstract. Includes bibliographical references.
12
Vilayannur, Natarajan Shankar. "Modeling the pneumatic relay valve of an s-cam air brake." Thesis, Texas A&M University, 2005. http://hdl.handle.net/1969.1/2363.
Full textAbstract:
Statistics indicate that defects in brake system contribute significantly to fatal crashes
involving commercial vehicles. Hence there is a need for developing preventive and
active safety measures for assessing the performance of an air brake system in trucks.
Existing techniques for assessing the performance of brakes are infrastructure
intensive, time and labor intensive. The premise of this thesis is that model-based
diagnostic techniques can be employed to overcome these limitations of existing tech-
niques. The design of a model-based diagnostic system requires the development and
experimental corroboration of a mathematical model of the evolution of pressure in
each brake chamber of a truck in response to the application of brake pedal input by
the driver, when there are no faults or defects in the brake system.
This thesis is aimed at modeling and experimentally corroborating a subsystem
of an air brake system, namely the pneumatic relay valve. The pneumatic relay
valve takes a input signal from the primary delivery of a treadle valve and meters
air from a storage reservoir to Type 30 rear brake chambers. A description of the
development of the model, the experimental setup and corroborating experimental
results are provided.
13
Jung, Ulrich Sebastian [Verfasser]. "Alternative Air Brake Concepts for Transport Aircraft Steep Approach / Ulrich Sebastian Jung." München : Verlag Dr. Hut, 2012. http://d-nb.info/1022535536/34.
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Higley, Joel. "The Brains of the Air Force: Laurence Kuter and the Making of the United States Air Force." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1469180142.
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Lee, Cho-Yu. "Computational and experimental study of air hybrid engine concepts." Thesis, Brunel University, 2011. http://bura.brunel.ac.uk/handle/2438/9205.
Full textAbstract:
The air hybrid engine absorbs the vehicle kinetic energy during braking, stores it in an air tank in the form of compressed air, and reuses it to start the engine and to propel a vehicle during cruising and acceleration. Capturing, storing and reusing this braking energy to achieve stop-start operation and to give additional power can therefore improve fuel economy, particularly in cities and urban areas where the traffic conditions involve many stops and starts. In order to reuse the residual kinetic energy, the vehicle operation consists of 3 basic modes, i.e. Compression Mode (CM), Expander Mode (EM) and normal firing mode, as well as stop-start operation through an air starter. A four-cylinder 2 litre diesel engine has been modelled to operate in four air hybrid engine configurations so that the braking and motoring performance of each configuration could be studied. These air hybrid systems can be constructed with production technologies and incur minimum changes to the existing engine design. The regenerative engine braking and starting capability is realised through the employment of an innovative simple one-way intake system and a production cam profile switching (CPS) mechanism. The hybrid systems will allow the engine to be cranked by the compressed air at moderate pressure without using addition starters or dedicated valves in the cylinder head. Therefore, the proposed air hybrid engine systems can be considered as a cost-effective regenerative hybrid powertrain and can be implemented in vehicles using existing production technologies. A novel cost-effective pneumatic regenerative stop-start hybrid system, Regenerative Engine Braking Device (RegenEBD), for buses and commercial vehicles is presented. RegenEBD is capable of converting kinetic energy into pneumatic energy in the compressed air saved in an air tank using a production engine braking device and other production type automotive components and a proprietary intake system design. The compressed air is then used to drive an air starter to achieve regenerative stop-start operations. The proposed hybrid system can work with the existing vehicle transmission system and can be implemented with the retro-fitted valve actuation device and a sandwich block mounted between the cylinder head and the production intake manifold. Compression mode operation is achieved by keeping the intake valves from fully closed throughout the four-strokes through a production type variable valve exhaust brake (VVEB) device on the intake valves. As a result, the induced air could be compressed through the opening gap of intake valves into the air tank through the intake system of proprietary design. The compressed air can then be used to crank the engine directly through the air expander operation or indirectly through the action of an air starter in production. A single cylinder camless engine has been set up and operated to evaluate the compression mode performance of two air hybrid concepts. The experimental results are then compared with the computational output with excellent agreement. In order to evaluate the potential of the air hybrid engine technologies, a new vehicle driving cycle simulation program has been developed using Matlab Simulink. An air hybrid engine sub-model and methodology for modelling the air hybrid engine’s performance have been proposed and implemented in the vehicle driving cycle simulation. The NEDC analysis of a Ford Mondeo vehicle shows that the vehicle can achieve regenerative stop-start operations throughout the driving cycle when it is powered by a 2.0litre diesel engine with air hybrid operation using a 40litre air tank of less than 10bar pressure. The regenerative stop-start operation can lead to 4.5% fuel saving during the NEDC. Finally, the Millbrook London Transport Bus (MLTB) driving cycle has been used to analyse the effectiveness of RegenEBD on a double deck bus powered by a Yuchai diesel engine. The results show that 90% stop-starts during the MLTB can be accomplished by RegenEBD and that a significant fuel saving of 6.5% can be obtained from the regenerative stop-start operations.
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Jung, Ulrich Sebastian [Verfasser], Christian [Akademischer Betreuer] Breitsamter, and Mirko [Akademischer Betreuer] Hornung. "Alternative Air Brake Concepts for Transport Aircraft Steep Approach / Ulrich Sebastian Jung. Gutachter: Mirko Hornung. Betreuer: Christian Breitsamter." München : Universitätsbibliothek der TU München, 2012. http://d-nb.info/1021499072/34.
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Melnik, Y., and T. Linnik. "Chemtrails impact on the environment and human brains." Thesis, Сумський державний університет, 2013. http://essuir.sumdu.edu.ua/handle/123456789/30866.
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Humans have undeniably affected the atmosphere and air quality of our planet. However, because most gasses are invisible to the human eye, it can be hard to physically see some of the changes we've brought about. Smog, exhaust from cars and trucks and smoke from chimneys and fires are a few of the visible signs, but one of the most intriguing visual manifestation of how we've changed the atmosphere are the jet trails left behind by airplanes.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/30866
18
Katz, Elliott. "Effect of Air-abrasion Preparation on Shear Bond Strength of Orthodontic Brackets to Enamel Surface." Thesis, NSUWorks, 2018. https://nsuworks.nova.edu/hpd_cdm_stuetd/75.
Full textAbstract:
Introduction: An optimal orthodontic bonding system must minimize damage to the enamel during conditioning, have enough bond strength to prevent bracket de-bonding during treatment, and allow bracket removal at treatment completion, such that minimal damage is inflicted to the tooth.1 Pumice followed by acid etching has been the standard for many years; however, Groman Inc. (Margate, FL, USA) has stated that using their air-abrasion product will result in a tripling of bond strength. This method claims a three-fold increase in bond strength compared to traditional acid etching techniques by substituting air-abrasion using the EtchMaster® (Groman Inc., Margate, FL) 50 μm aluminum oxide in place of pumice prophy prior to acid etching. The purpose of this study is to see if this combination does in fact triple shear bond strength, and if so, what impact it has on the residual enamel surface after bracket removal, or de-bonding. Methods: Ninety recently extracted bovine incisors were randomly divided into three groups. Each of the three groups underwent different conditioning methods prior to bracket bonding. Group A: pumice + acid etch (N=30), Group B: air-abrasion + acid etch (N=30), and Group C: air-abrasion only (N=30). Enamel surface conditions were characterized using a Quanta 200 Scanning Electron Microscope (SEM) (FEI, Hillsboro, OR) and a SZX7 Stereomicroscope System (Olympus, Center Valley, PA). American Orthodontics Master Series System twin MBT mandibular incisor brackets (Sheboygan, WI, USA) were then bonded to each tooth. Following bonding, teeth were stored for twenty-four hours in water at 37°C +/- 2°C. All groups then underwent thermocycling of five hundred cycles in water baths set at five and fifty-five degrees Celsius. Next, the samples were mounted in dental stone and brackets de-bonded using a universal testing machine (Instron, Canton, MA) to obtain shear bond strength (SBS) values. SEM and optical stereomicroscopy were again utilized to evaluate the enamel surface and determine the adhesive remnant index (ARI) was score of each specimen. Results: The mean of Group A (pumice + acid etch) was 21.52 MPa with a standard deviation of 4.97 MPa. The mean of Group B (air-abrasion + acid etch) was 21.83 MPa with a standard deviation of 7.55 Mpa. The mean of Group C (air-abrasion only) was 8.12 MPa with a standard deviation of 3.05 MPa. Analysis of variance showed a main effect of Group on MPa, F(2, 87) = 60.66, p < 0.001, ηp2= 0.58. Post-hoc analyses using Tukey’s HSD indicated that SBS values were higher for teeth in Group A than for those in Group C (p < 0.001), teeth in Group B had higher SBS values than those in Group C (p < 0.001), but no difference was found for SBS between teeth in Group A and Group B (p =0.981). Results from the Fisher’s Exact test, where we controlled the Type I error using a Bonferroni correction, reveals that ARI scores differed by group (p < 0.001). Stereomicroscope images at 38.75x magnification obtained following enamel conditioning show Groups A (P+AE) and B (AA+AE) are almost indistinguishable; however, Group C (AA) has visual differences. Group C had a speckled reflective property that appeared to be residual aluminum oxide particles. Following de-bond, stereomicroscopic and SEM images showed no enamel defects on the tooth. Conclusions: SBS was not significantly different between Group A (pumice + acid etch) and Group B (air-abrasion + acid etch). SBS was significantly different between Groups A and B, and Group C (air-abrasion only). This means there is not a three-fold increase in SBS when using air-abrasion and acid etch, when compared to pumice and acid etch, as claimed by the manufacturer of the air-abrasion unit used in this study. Additionally, the air-abrasion only group displayed a significantly lower SBS than Group A and B. Air-abrasion only is not a suitable enamel preparation method for orthodontic bonding. Images obtained from the stereomicroscope and SEM reveal no observational damage to the enamel surface topography after de-bonding for any group.
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Karanja, Bethuel, and Parsa Broukhiyan. "Commercial Vehicle Air Consumption: Simulation, Validation and Recommendation." Thesis, KTH, Maskinkonstruktion (Inst.), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-209657.
Full textAbstract:
This report details the work done in a master thesis project. The project was conducted at the Brake Performance Department at Scania CV AB. The project involves the development of a numerical model (in Matlab) that calculates and predicts air consumption in a truck under different drive cycles. The report first details tests and experiments done so as to acquire the necessary information for the development of the model. The report then presents the model that was created and delves into tests that were conducted for its validation. A model is created that allows the user to select different component combinations on the trucks along with different loading scenarios and drive cycles. Finally the model is used to evaluate air consumption in trucks during particularly strenuous cycles. The model developed is found to be reliable and accurate to with 7% with regard to amount of air consumed. With its help, several recommendations on how air consumption in commercial vehicles can be improved are made. The best components’ combination is also found and presented.I denna rapport beskrivs ett examensarbete som genomfördes på bromsavdelningen på Scania CV AB. Projektet innefattar utveckling av en numerisk modell (i Matlab) som beräknar och förutspår luftförbrukningen i en lastbil under olika körcykler. I rapporten beskrivs det tester och experiment som gjordes för att ta fram nödvändiga uppgifter för utvecklingen av modellen. Sedan presenteras modellen som skapades och alla valideringstester som genomfördes. Modellen är gjord så att användaren kan kombinera olika komponentkombinationer för lastbilar med olika lastningskonfigurationer och körcykler. Slutligen används modellen för att utvärdera luftförbrukningen i lastbilar under särskilt ansträngande körcykler. Den utvecklade modellen visade sig vara pålitlig och korrekt med en felmarginal på 7% med avseende på mängden luft som konsumeras. Med dess hjälp kunde flera rekommendationer ges om hur luftförbrukningen i kommersiella fordon kan förbättras. De bästa komponentkombinationerna hittades också och presenteras i denna rapport
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Karlqvist, Rasmus. "Hydropneumatic suspension in a truck : Installation of a hydropneumatic suspension for a Scania truck." Thesis, Karlstads universitet, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-78647.
Full textAbstract:
Investigation and testing of hydropneumatic suspension systems has previously been done at Scania between the year 1992 and 2000. Interest has aroused at Scania CV AB to further test a hydropneumatic suspension. The reason being the new ventures of decarbonised, clean, electrified, automatized and digitalised vehicles. If electrified trucks are to be adopted in the market as an alternative to trucks with combustion engines, solutions for this type of vehicle’s capacity need to be presented. The vehicle’s weight needs to be reduced; the effectiveness of the components needs to be increased and alternatives to increase battery storage needs to arise if it’s going match the traveling distance of a combustion engine. The mission of the project is to present an installation solution of a hydropneumatic suspension that retains the performance of the current air suspension. The presented material will contain CAD-models of all the brackets that will be designed to fit the suspension, as well as the placement in the vehicle assembly for said brackets. The results show that as for the front suspension the best solution is a placement of the hydraulic cylinders in front of the vehicles front axle. Furthermore the rear suspension is best suited for a placement of the hydraulic cylinders behind the vehicles rear axle. However it was concluded that the rear suspension will not be able to retain the current stroke of the vehicle without sacrificing its ground clearance. Parts of the suspension could however be terminated when the air suspension system was replaced by the hydropneumatic system namely: The front suspension anti-roll bar, shock absorbers, air springs and their coexisting brackets.
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Jíša, Martin. "Konstrukce brzdičky příze s mechanickým přidržováním stroje Air-Jet." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2016. http://www.nusl.cz/ntk/nusl-241705.
Full textAbstract:
This diploma thesis describes methods of textile fibers treatment, production levels with detailed focus on spinning process especially by Rieter AG in Winterthur, Switzerland, subsidiary company in Usti nad Orlici. Thesis also describes production materials and it’s behavior in relations to production machines. Analysis of the current solution, it’s pros and cons is also done. Setting of requirements of new solution. Creating proposals of design solutions of yarn keeper with mechanic clamp situated on spinning unit on Air-Jet machine. Creating concepts and proposal schemes. After choosing of best possible solution considering production costs, electric consumption during working machine and during active cycle was this variation produce. At the end is review of complete solution and prospective next steps in testing not only in laboratory and prospects of using in field.
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Linn, Jane Ostergar. "A Coverage Metric to Aid in Testing Multi-Agent Systems." BYU ScholarsArchive, 2017. https://scholarsarchive.byu.edu/etd/6666.
Full textAbstract:
Models are frequently used to represent complex systems in order to test the systems before they are deployed. Some of the most complicated models are those that represent multi-agent systems (MAS), where there are multiple decision makers. Brahms is an agent-oriented language that models MAS. Three major qualities affect the behavior of these MAS models: workframes that change the state of the system, communication activities that coordinate information between agents, and the schedule of workframes. The primary method to test these models that exists is repeated simulation. Simulation is useful insofar as interesting test cases are used that enable the simulation to explore different behaviors of the model, but simulation alone cannot be fully relied upon to adequately cover the test space, especially in the case of non-deterministic concurrent systems. It takes an exponential number of simulation trials to uncover schedules that reveal unexpected behaviors. This thesis defines a coverage metric to make simulation more meaningful before verification of the model. The coverage metric is divided into three different metrics: workframe coverage, communication coverage, and schedule coverage. Each coverage metric is defined through static analysis of the system, resulting in the coverage requirements of that system. These coverage requirements are compared to the logged output of the simulation run to calculate the coverage of the system. The use of the coverage metric is illustrated in several empirical studies and explored in a detailed case study of the SATS concept (Small Aircraft Transportation System). SATS outlines the procedures aircraft follow around runways that do not have communication towers. The coverage metric quantifies the test effort, and can be used as a basis for future automated test generation and active test.
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Cury, Sérgio Elias Neves. "Exposição dos bráquetes ao meio bucal durante o tratamento ortodôntico e seu impacto no atrito." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/25/25144/tde-31082018-175858/.
Full textAbstract:
O objetivo desse trabalho foi avaliar as alterações nas ranhuras dos bráquetes após uso clínico e o seu impacto na alteração da força de atrito. Para isso foi realizada uma revisão sistemática da literatura, e um estudo prospectivo comparando os níveis de atrito antes e depois do uso clínico dos bráquetes, assim como comparando dois diferentes materiais para jateamento profilático. A revisão sistemática avaliou 7 artigos que cumpriram os devidos critérios de inclusão, a partir de busca eletrônica realizada em diversas bases de dados, sem limitações quanto a data e o idioma. Foram avaliados quanto a qualidade metodológica, e ao risco de viés de acordo com uma versão modificada do checklist de Donws and Black. 6 dos 7 artigos apresentaram resultados com aumento significativo da força de atrito após o bráquete ser submetido ao uso clínico. O segundo estudo do presente trabalho se trata de um estudo prospectivo in-vivo, ao qual 16 pacientes, submetidos a tratamento ortodôntico com bráquetes metálicos convencionais, compuseram 3 grupos de acordo com o protocolo de controle profilático realizado nos bráquetes de 2ºs pré-molares (Grupo 1 - pacientes submetidos à profilaxia com jateamento à base de bicarbonato de sódio; Grupo 2 pacientes submetidos à profilaxia com jateamento à base de glicina; Grupo 3 pacientes não foram submetidos à profilaxia profissional) Os bráquetes foram posteriormente removidos da cavidade oral e submetidos a ensaios de força de atrito, além de análise qualitativo da rugosidade superficial por microscopia eletrônica de varredura. O grupo controle (GC) para comparação foi constituído por bráquetes novos não submetidos à exposição em cavidade bucal. O teste de ANOVA seguido pelo teste Tukey foram utilizados para avaliar as diferenças entre os 4 grupos (GC, G1, G2 e G3). Os grupos de bráquetes usados apresentaram aumento da força de atrito, porém apenas o grupo que não foi realizado jateamento profilático a cada consulta (G3), apresentou diferença estatisticamente significante em relação ao Grupo Controle. Não houve diferença estatisticamente significante também quando comparados os dois diferentes materiais utilizados para o jateamento profilático.The aim of this study was to evaluate the changes in bracket slots after clinical use and their impact on friction force. It is composed by a systematic review of the literature and a prospective study comparing the friction levels before and after the clinical use, as well as comparing two different materials for prophylactic blasting. The systematic review evaluated 7 articles that satisfied the inclusion criteria, based on electronic searches conducted in several databases, without limitations regarding publication year or language. The methodological quality and risk of bias were assessed according to a modified version of the Donws and Black checklist. 6 of the 7 articles presented significant increase in the friction force on retrieved brackets, after clinical use. The second study of the present study is a prospective in-vivo study which 16 patients were submitted to orthodontic treatment, divided in 3 groups according to the protocol of prophylactic control performed in brackets (Group 1 - patients submitted prophylaxis with sodium bicarbonate blasting, Group 2 - patients submitted to prophylaxis with glycine-based blasting, Group 3 - patients were not submitted to professional prophylaxis) Brackets were later removed from the oral cavity and subjected to friction force tests, in addition to qualitative analysis of surface roughness by scanning electron microscopy. The control group (CG) for comparison consisted of as received brackets (brand new brackets). The ANOVA test followed by the Tukey test were used to evaluate the differences between the 4 groups (GC, G1, G2 and G3). The retrieved groups presented an increase on friction force, but only the group that did not perform prophylactic blasting every appointment (G3) presented a statistically significant difference in comparison to the Control Group. There was no statistically significant difference also when comparing the two different materials used for prophylactic blasting.
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Šproch, Daniel. "Návrh výroby držáku klimatizace." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-230516.
Full textAbstract:
The holder of outdoor air-conditioning units are made out of steel 11 321.21 with 2mm thickness. The production quantity is 2000 units / year. The holder is produced using CNC machine for cutting and bending on CNC press brake. The semi-finished product is a metal sheet (2 x 2000 x 1000 mm). Part of this diploma thesis is to design of the population with the punching tools, the layout of parts on the metal sheet and design of appropriate press brake punches and dies. The conclusion contains economic evaluation of the proposed solution.
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Turabi, Ali, and Алі Абутураб Торабі. "Preliminary design of a long-range passenger aircraft with a 364 passenger capacity." Thesis, National Aviation University, 2021. https://er.nau.edu.ua/handle/NAU/53185.
Full textAbstract:
Робота публікується згідно наказу Ректора НАУ від 27.05.2021 р. №311/од "Про розміщення кваліфікаційних робіт здобувачів вищої освіти в репозиторії університету". Керівник роботи: доцент, к.т.н. Юцкевич Святослав СергійовичThis diploma work is dedicated to preliminary design of the long-range aircraft with 364 passenger capacity. The process of development is analysis of the prototypes and selections of the most progressive involve decisions. The diploma work has drawings of project of the long-range airplane with 364 passenger capacity, calculations and drawings of the aircraft layout.
Ця дипломна робота присвячена ескізному проекту дальньомагістрального літака на 364 пасажири. Процес розробки - це аналіз прототипів і відбір найбільш прогресивних рішень. Дипломна робота містить креслення проекту дальньомагістрального літака на 364 пасажири, розрахунки та креслення компоновки літака.
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Storm, Jessica L. "How External Factors Influence Higher Education Philanthropy." Ohio University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1572006791377665.
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Vice, President Research Office of the. "Livable Communities." Office of the Vice President Research, The University of British Columbia, 2009. http://hdl.handle.net/2429/9515.
Full textAbstract:
What makes a community sustainable? Is it the
effective management of local environmental
resources? Or meeting the social, economic and health needs of its population? For the five UBC researchers in the following pages, the answer is unequivocally both. From tackling water scarcity to environmental health and planning, these researchers are individually working to ensure local communities are equipped with the necessary knowledge to remain sustainable for generations to come.
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Dhar, Sandeep. "Development of Diagnostic Algorithms for Air Brakes in Trucks." Thesis, 2010. http://hdl.handle.net/1969.1/ETD-TAMU-2010-08-8438.
Full textAbstract:
In this dissertation, we focus on development of algorithms for estimating the severity
of air leakage and for predicting the out-of-adjustment of pushrod in an air brake
system of heavy commercial vehicles. The leakage of air from the brake system
causes a reduction in the steady-state pressure in the brake chamber and an increase
in the lag of the braking pressure response thereby increasing the stopping distance
of the vehicle. Currently a presence of leak in the system is detected for the severities
of leak that cause the reservoir pressure to drop below a threshold, such as, the
leakage of compressed air due to rupture of the reservoir or of the hoses carrying the
compressed air. The leakage of air is also possible due to several other reasons such
as, cracks in the hoses, loose couplings between the hoses etc. The severities of leak,
corresponding to such situations, do not lead to the reservoir pressure drop below
the threshold; therefore, their presence remains undetected. For the detection and
estimation of such severities of leak, a diagnostic scheme has been given and is based
on a model developed for the mass
ow rate of the leakage of air from the air brake
system.
Out-of-adjustment of the pushrod is the extension of pushrod beyond a prede-
ned value and for safety concerns, an extension beyond this value is not desired.
Currently no warning system is available for monitoring the out-of-adjustment of
pushrod, except, during the safety inspection. Inspection of the pushrod for outof-
adjustment is the most labor-intensive and time consuming task during a typical
safety inspection procedure. For efficient and continuous monitoring of the pushrod
for out-of-adjustment, a diagnostic algorithm for estimating the steady-state pushrod
stroke has been developed. The scheme is expected to expedite the inspection process
for the out-of-adjustment of pushrod. Experimental data from the air brake test
setup at Texas A and M University has been used for corroborating both the models.
Also, the problem of parameter estimation of sequential hybrid systems such as
the air brake system, has been addressed. The \hybrid" nature of the air brake system
stems from the system being in di erent modes corresponding to di erent values
of the displacement of the pushrod and is a result of di erent spring compliances
associated with the pushrod in di erent ranges of its displacement. The air brake
system is \sequential" in the sense that as the pressure increases, the displacement
of the pushrod increases and there is a distinct sequence of modes that the system
will transition through and upon a reduction in pressure, the sequence of modes is
revisited in the reverse order. The mode to mode transition of the air brake system
is governed by the parameters, such as, the clearance between the brake pad and
the brake drum. The problem of estimation, that has been addressed, is as follows:
Suppose the pressure in the air brake system were to be measured and that the motion
of the pushrod is not measured. Is it possible to estimate the nal displacement of
the pushrod without knowing the parameters, such as the clearance, that govern the
system to transition from one mode to another?
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(9830255), Ian Ripley. "An investigation of brake application delays in Australian train brake systems." Thesis, 2004. https://figshare.com/articles/thesis/An_investigation_of_brake_application_delays_in_Australian_train_brake_systems/13422623.
Full textAbstract:
An investigation of brake application delays in Australian train brake systems began with a literature review of pneumatic train braking systems. Data located in the review gave examples of brake application delays of pre 1990 designs from the U.K., India and North America. Information on application delays on later Australian designs was scarce. Reading of literature has shown a difference between the Australian and North American control valves in the way the propagation of the pressure reduction rate in the brake pipe is maintained. Control valves of the North American style allow the brake pipe air to be connected for a short time to a small cavity or quick service volume of each valve. The quick service volume is then released to atmosphere. The action of exhausting a small amount of air from the brake pipe helps to ensure a propagation of an adequate pressure reduction rate as it travels to the next valve. Australian control valves rely on the ratio of the volume of brake pipe between control valves and the size of the quick service volume or bulb to ensure the propagation of an adequate pressure reduction as it travels to the next valve. The air in a bulb of an Australian valve is not expelled to atmosphere until a brake release is made. The research explored possible reductions in application delays by utilizing an experimental pipe test rack that included 4 control valves and 120 meters of brake pipe. Experiments with different configurations of exhaust orifices or chokes, valves and branch pipe lengths that supplied the valves gave a record acquired by data acquisition of the timing of each valve and the local pressure drop from a valve or each valve for comparison. Experiments with exhaust chokes that gave a reduction drop rate in the brake pipe that approached the minimum required to operate a control valve resulted in instability of the application operation of the control valve. The quick service volume of different sizes was included in the experiments to give comparisons in the propagation of the pressure reduction toward the end of a long train. Further increases into the size of the bulb of a control valve to enhance the propagation features toward the end of a long train are discussed. The branch pipe with different diameters from 12 mm to 20 mm and lengths from 160 mm to 800 mm when fitted to an adaptor pipe bracket were investigated and results show that larger diameters gave larger gulps in the brake pipe. Other components that were studied included the pipe bracket that is fitted on some control valves. The pipe bracket and isolation cock was found to add 282 mm of additional length to the air path and while not changing the operation of the valve, the results showed a smaller drop in local pressure in the brake pipe to assist the pressure reduction rate than shown in valves without pipe brackets.
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Lin, Hsiu-Ching, and 林秀青. "Development and Evaluation of the Air Bag Monitoring System used in the Braces for Idiopathic Scoliosis." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/93346364241154843062.
Full textAbstract:
碩士國立成功大學
醫學工程研究所
91
The conventional spinal orthoses have been confirmed to be effective in altering the natural history of adolescent idiopathic scoliosis (AIS) and their effectiveness varies from 72% to 89% of the cases being treated. In view of the biomechanics, to improve the correcting ability, the correction force provided by the orthosis should be maintained within the effective range considering its dynamic use condition during the long period of wearing. The conventional orthotic pad only can provide static and constant corrective force. The aim of this study was to investigate the treatment effect prospectively by applying a quasi-dynamic correction force on the scoliosis with the adjustable air bag. To quantify the correction pressure applied by the air bag and the interface pressure between the orthosis and body, a pressure monitoring system to detect the correction fore supplied by the air bag was developed and the feasibility was also evaluated. To develop this air bag pressure monitoring system, four sensors (BP-2KRS pressure sensor, FSR, PS-02 and PS-01) including force and pressure sensors, were evaluated and corresponding data loggers were established to examine the possibility of setting up a portable system. The developed pressure monitoring system was further evaluated on one normal subject and two AIS patients to assess its ability in detecting the pressure (force) changes during different postures of daily activities. The evaluation results indicated that the resolution of FSR and PS-02 sensors were too low to sense the pressure. The PS-01 force sensor was determined for the air bag pressure monitoring system, because the BP-2KRS sensor is too heavy and expensive. The follow-up results indicated that high correlation existed between the interface pressure of air bag measured by the BP-2KRS pressure sensor and the interface force of air bag measured by the PS-01 for all subjects (correlation coefficient = 0.985~0.734, p<0.05). Therefore, the design of a portable air bag monitoring system has the capability to measure the interface pressure change between the orthosis and body for clinical use. As for the postural effect, trunk flexion had larger influence on the correction force than trunk extension. The reasons might be the range of motion and a gap developed between the orthosis and the trunk. In the mean while, when the subject performed trunk side bending toward the ipsilateral side of the air bag did not increase the correction force by over-pressed on it. The research findings indicated that postures indeed affected the corrective force of the orthosis; hence, a pressure monitoring system to quantify the alteration of correction force in real-time is necessary. The objectives of this study were to develop an air bag pressure monitoring system installed within the spine orthosis system and to evaluate its feasibility. In the future, further refinement of this system is required for clinical use. The investigation of using air bag pressure monitoring system integrated with electrical stimulation for spinal curve correction is suggested for future work.
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Hsueh, Tsung-Chih, and 薜宗智. "Computer Aid Analysis and Design of The Drum Brake Plate Motorcycle." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/24516719909563406736.
Full textAbstract:
碩士國立中山大學
機械工程研究所
85
The main goal of this study is to study the effect of combining the computer-aided design and finite element method for alalysis and design on the drum brake of a motorcycle. Be utilizing the computeraided design package IDEAS which is signified with convenient drawing and construction of a complex model that is near the truth, the researcher transformed the model's information into the finite element method package MARC, and did the analysis of dynamic and contact problem. In accordance with the result of analysis, the researcher changed some parameters and did further analyse. After discussing the results of parameters, the researcher used those information to improve the mechanism of drum brkae.
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Chien, Ming-Chun, and 簡名君. "The Research on Evaluation of Deterioration of Subsidiary on Building Exterior Wall –As a Case Study on Separate Type Air – Condition Bracket." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/7vnj43.
Full textAbstract:
碩士國立臺北科技大學
建築與都市設計研究所
97
Having a healthy living environment is one of the important issues in the 21th century. In addition, the healthy diagnosis of the building is head for the process of legalization in the future. However, as time goes by, the life cycle of the buildings would be cut down to incapable depend on their materiels and structures. The critical problem is the damages caused by the falling could make people fear and cause doubts of the public safety. As a result, this research is written from the viewpoints of risk management. Also, risk control is to influence the distribution of the probability by means of the exterior wall accessories diagnosis and supervise the possibility of accidently rate. Therefore, the goal of this reasearch is to establish categories and deterioration evaluation, set up the SOP (Standard of Process) of the evaluation of air conditioner, increase the overall performance, build up the analysis of decision tree analysis, and bring up the solving strategies. The scope of the reasearch is limited to the mainly assembling rack of the air conditioner on building facade. Besides, the analysis of the case study and the interviews with air conditioner assemblers are combined to set up the standard of rank-estimating of the exterior wall accessories, in order to become module of evaluation of deterioration through academic analysis, field survey, and interviews. Base on the results of the research, the contribution of this report is to support building evaluators effectively and accurately in diagnosing the exterior wall accessories and evaluating the standard of deterioration rank. As the reference of safety maintainance and healthy diagnosis, three types of SOP are provided to evaluate the exterior wall accessories- the rack of air conditioner. 1.Type A diagnosis- Basic dianosis→Advanced diagnosis→Comprehensive diagnosis→Increase the overall performance 2.Type B diagnosis- Advanced diagnosis→Comprehensive diagnosis→Increase the overall performance 3.Type C diagnosis- Comprehensive diagnosis→Increase the overall performance