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Refinement and Investigation of Instruments for Emission Screening of Passenger Cars / Förfining och undersökning av instrument för emissions-kontroll av personbilarRuderer, Marcus, Stéen, Signe January 2022 (has links)
A Portable Emissions Measurement System (PEMS) is widely used for analysing the emissions of a vehicle. However, the PEMS is quite cumbersome and time-consuming to use for vehicle testing. This thesis investigates the possibilities of a Smart Emissions Measurement System (SEMS) and how it correlates to the more advanced PEMS. The second factor is of a shortened drive cycle, and how it is compared to the legislated drive cycle. The main hypothesis of this thesis was that a shortened drive cycle with the SEMS equipment should be able to predict the outcome of a full Real Driving Emissions (RDE) test with PEMS equipment with a statistical significance that is large enough to prove the SEMS to be a useful tool. The experiment was performed with a PEMS in parallel with a SEMS on both a shortened and a legislated drive cycle. The study concludes that the SEMS is showing promising results as to how well an RDE test can be predicted, and it would be a useful resource to increase testing on vehicles, both on a shortened and a legislated route. However, as the emissions of light-duty vehicles get smaller, they also get harder to measure with accuracy. This will always be a problem for the SEMS equipment, and even more on a shortened route. As a future application for light-duty vehicles, this might not be the perfect system due to many inaccuracies, but there are many other applications where SEMS could be useful with enough precision, such as heavier and older vehicles. / Portable Emissions Measurement System (PEMS) används i stor utsträckning för att analysera utsläpp av fordon. PEMS är dock ganska besvärligt och tidskrävande att använda vid fordonstestning. Det här examensarbetet undersöker möjligheterna med Smart Emissions Measurement System (SEMS) och hur det korrelerar med PEMS. Den andra faktorn som undersöks är en förkortad körcykel och hur den jämförs med den lagstadgade körcykeln. Huvudhypotesen i det här examensarbetet var att en förkortad körcykel med SEMS bör kunna förutsäga resultatet av ett fullständigt Real Driving Emissions (RDE)-test med PEMS med en tillräckligt stor statistisk signifikans för att visa att SEMS är ett användbart verktyg. Studien utfördes med PEMS parallellt monterat med SEMS på både en förkortad och en lagstadgad körcykel. Studien drar slutsatsen att SEMS visar lovande resultat för hur väl ett RDE-test kan förutsägas, och det skulle vara en användbar resurs för att öka testningen av fordon, både på en förkortad och en lagstadgad körcykel. Eftersom utsläppen från lätta fordon blir allt lägre, blir de även svårare att mäta med noggrannhet. Det kommer alltid att vara ett problem för SEMS, och särskilt på en förkortad rutt. Som en framtida applikation för lätta fordon kanske SEMS inte är det perfekta systemet på grund av att det inte är särskilt precist, men det finns många andra applikationer där SEMS kan vara användbart och där det har tillräcklig precision, så som för tyngre och äldre fordon.
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Design of a Real-Time Scanning Electrical Mobility Spectrometer and its Application in Study of Nanoparticle Aerosol GenerationSingh, Gagan 2010 May 1900 (has links)
A real-time, mobile Scanning Electrical Mobility Spectrometer (SEMS) was designed using a Condensation Particle Counter (CPC) and Differential Mobility Analyzer (DMA) to measure the size distribution of nanoparticles. The SEMS was calibrated using monodisperse Polystyrene Latex (PSL) particles, and was then applied to study the size distribution of TiO2 nanoparticle aerosols generated by spray drying water suspensions of the nanoparticles. The nanoparticle aerosol size distribution, the effect of surfactant, and the effect of residual solvent droplets were determined.
The SEMS system was designed by integrating the Electrical System, the Fluid Flow System, and the SEMS Software. It was calibrated using aerosolized Polystyrene Latex (PSL) spheres with nominal diameters of 99 nm and 204 nm. TiO2 nanoparticle aerosols were generated by atomizing water suspensions of TiO2 nanoparticles using a Collison nebulizer. Size distribution of the TiO2 aerosol was measured by the SEMS, as well as by TEM. Furthermore, the effect of surfactant, Tween 20 at four different concentrations between 0.01mM and 0.80mM, and stability of aerosol concentration with time were studied. It was hypothesized that residual particles in DI water observed during the calibration process were a mixture of impurities in water and unevaporated droplets. Solid impurities were captured on TEM grids using a point-to-plane Electrostatic Precipitator (ESP) and analyzed by Energy Dispersive Spectroscopy (EDS) while the contribution of unevaporated liquid droplets to residual particles was confirmed by size distribution measurements of aerosolized DI water in different humidity conditions. The calibration indicated that the mode diameter was found to be at 92.5nm by TEM and 95.8nm by the SEMS for 99nm nominal diameter particles, a difference of 3.6%. Similarly, the mode diameter for 204nm nominal diameter particles was found to be 194.9nm by TEM and 191nm by SEMS, a difference of 2.0%. Measurements by SEMS for TiO2 aerosol generated by Collison nebulizer indicated the mode diameters of 3mM, 6mM, and 9mM concentrations of TiO2 suspension to be 197.5nm, 200.0nm and 195.2nm respectively. On the other hand, the mode diameter was found to be approximately 95nm from TEM analysis of TiO2 powder. Additionally, concentration of particles generated decreased with time. Dynamic Light Scattering (DLS) measurements indicated agglomeration of particles in the suspension. Furthermore, the emulation of single particle distribution was not possible even after using Tween 20 in concentrations between 0.01mM and 0.80mM. From the study of residual particles in DI water, it was found that residual particles observed during the aerosolization of suspensions of DI water were composed of impurities present in DI water and unevaporated droplets of DI water. Although it was possible to observe solid residual particles on the TEM grid, EDS was not able to determine the chemical composition of these particles.
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體驗行銷策略研究-以好市多(Costco)為例 / The Study of experiential marketing strategy: The case of costco許泓祺, Hsu, Hong Chi Unknown Date (has links)
與傳統行銷相反,Schmitt(1999)提出的體驗行銷將焦點放在顧客體驗上,提供知覺的、情感的、認知的、行為的以及關係的價值來取代功能價值,不同於商品與服務停留在顧客之外,體驗可以深入到顧客的內在,並將其價值持續的延續,有助於品牌的記憶與區隔。
本研究以好市多(Costco)做為研究案例,透過質化與量化研究探討策略體驗模組SEMs(感官、情感、思考、行動、關聯策略模組)、體驗價值(投資報酬、卓越服務、美感、趣味性價值)、顧客滿意度與顧客忠誠度間之關係,並提出實務的建言。
研究結果發現如下:
一、透過適當的「策略體驗模組」可正向強化不同構面的「體驗價值」。
二、「策略體驗模組」五個構面以及「體驗價值」四個構面皆可正向強化「顧客滿意度」。
三、關聯體驗、情感體驗、行動體驗都可以影響忠誠度,「關聯體驗」訴求品牌社群的意識與凝聚對「顧客忠誠度」影響力最大。
四、體驗價值中僅有「美感價值」無法影響「顧客忠誠度」,剩餘構面中影響力最大則是「趣味性價值」。
五、顧客滿意度可以有效預測顧客忠誠度。 / Different from traditional marketing theory, experiential marketing (Schmitt 1999) focuses on customer experience, offering customer the value of sense, feel, think, act & relate to take place of traditional marketing functional value. Products & services can only touch customers’ outside, but experience can go inside customers’ hearts, and the value of experience will last for a very long time. To use experiential marketing well will help enterprise brand outperform others and memorized by customers.
This research uses Costco as the case to study the relationship of SEMs(Sense, Feel, Think, Act & Relate), experiential value(CROI, Service Excellence, Aesthetics, & Playfulness), customer satisfaction, and customer loyalty. Also at the end, this research will offer practical suggestions to Costco.
Our findings as following:
1.By choosing right modules of SEMs can positively predict or influence all aspects of experiential value.
2.All five modules of SEMs and four aspects of experiential value can positive predict or influence customer satisfaction.
3.Relate, Feel, & Act modules can positively predict or influence customer loyalty. Relate module appealing to the coherence of brand community is the most important factor to predict customer loyalty.
4.Only Aesthetics can’t positively predict customer loyalty. For the rest, Playfulness is the most important factor to influence customer loyalty.
5.Customer satisfaction can positively predict customer loyalty.
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