title: Investigation of exhaust chamber resonance for single-cylinder Formula SAE based engines

authors: van Harselaar, Jonathan

abstract: Noise pollution is a factor that affects many people in their day to day lives. One of the more prevalent forms of noise is generated from passenger vehicles. With this in mind, vehicle manufacturers design and stringently test their mufflers that are bound for vehicles to ensure they provide the optimum characteristics needed to lower noise to suitable levels. In addition, these manufacturers continue to be proactive in researching improved methods of the design and build aspects of their vehicles, so it is common to see large production companies sponsoring development and racing events. One such event is the Formula SAE competition.
This competition series is aimed at university students who design, build, and race their vehicle against other universities globally. Formula SAE is designed to provide students with valuable experience in a range of topics as both static and dynamic events occur and are judged. Consequently, the competition has evolved into more than just a racing series, it also includes business presentations, costing reports, and design judging.
With more Formula SAE teams moving to single-cylinder engines, noise suppression is becoming an important issue from the exhaust noise characteristics of the large engines available today. As part of the competition, performance is judged based on set criteria for engine noise emissions at different engine speeds. Many teams struggle with this aspect of the competition, where a fail in this test commonly leads to crude forms of noise suppression being quickly added to the vehicle, which in turn usually results in lowering performance. If a team cannot pass the noise tests, then subsequently they are not allowed to enter any of the dynamic events.
This thesis aims to compare theoretical results with measured values for different configurations of exhaust chambers. Inline exhaust chambers have been selected as the topic of interest due to the low-frequency exhaust characteristics of single-cylinder engines suiting the attenuation characteristics of this style of silencing device. The outcome of this research should provide figures and values for future Formula SAE teams to work with in their initial muffler and chamber design. By having this data available, selection of correct parameters will be a more straight-forward process and should assist in building a muffler that will be more assured of passing noise tests at competition.

text: Investigation of exhaust chamber resonance for single-cylinder Formula SAE based engines Noise pollution is a factor that affects many people in their day to day lives. One of the more prevalent forms of noise is generated from passenger vehicles. With this in mind, vehicle manufacturers design and stringently test their mufflers that are bound for vehicles to ensure they provide the optimum characteristics needed to lower noise to suitable levels. In addition, these manufacturers continue to be proactive in researching improved methods of the design and build aspects of their vehicles, so it is common to see large production companies sponsoring development and racing events. One such event is the Formula SAE competition.
This competition series is aimed at university students who design, build, and race their vehicle against other universities globally. Formula SAE is designed to provide students with valuable experience in a range of topics as both static and dynamic events occur and are judged. Consequently, the competition has evolved into more than just a racing series, it also includes business presentations, costing reports, and design judging.
With more Formula SAE teams moving to single-cylinder engines, noise suppression is becoming an important issue from the exhaust noise characteristics of the large engines available today. As part of the competition, performance is judged based on set criteria for engine noise emissions at different engine speeds. Many teams struggle with this aspect of the competition, where a fail in this test commonly leads to crude forms of noise suppression being quickly added to the vehicle, which in turn usually results in lowering performance. If a team cannot pass the noise tests, then subsequently they are not allowed to enter any of the dynamic events.
This thesis aims to compare theoretical results with measured values for different configurations of exhaust chambers. Inline exhaust chambers have been selected as the topic of interest due to the low-frequency exhaust characteristics of single-cylinder engines suiting the attenuation characteristics of this style of silencing device. The outcome of this research should provide figures and values for future Formula SAE teams to work with in their initial muffler and chamber design. By having this data available, selection of correct parameters will be a more straight-forward process and should assist in building a muffler that will be more assured of passing noise tests at competition.

year: 2019

title: A forward-looking measure of the stock of human capital in New Zealand

authors: Le, Trinh

subjects: human capital

abstract: Human capital is increasingly believed to play an important role in the growth process; however, adequately measuring its stock remains controversial. Because the estimated impact that human capital has on economic growth is sensitive to the measures or proxies of human capital, accurate and consistent measures are needed. While many measures of human capital have been developed, most rely on some proxy of educational experience and are thus plagued with limitations. In this study, we modify the lifetime labour income approach outlined by Jorgenson and Fraumeni (The Measurement of Savings, Investment and Wealth, Chicago, IL, University of Chicago Press, 1989, pp. 227–282; Output Measurement in the Services Sector, Chicago, IL, University of Chicago Press, 1992, pp. 303–338) to estimate the monetary value of the human capital stock for New Zealand. Based on data from the New Zealand Census of Population, we find that the country's working human capital grew by half between 1981 and 2001, mostly due to the rise in employment level. This stock of human capital was also well over double that of physical capital in all the census years studied.

text: A forward-looking measure of the stock of human capital in New Zealand Human capital is increasingly believed to play an important role in the growth process; however, adequately measuring its stock remains controversial. Because the estimated impact that human capital has on economic growth is sensitive to the measures or proxies of human capital, accurate and consistent measures are needed. While many measures of human capital have been developed, most rely on some proxy of educational experience and are thus plagued with limitations. In this study, we modify the lifetime labour income approach outlined by Jorgenson and Fraumeni (The Measurement of Savings, Investment and Wealth, Chicago, IL, University of Chicago Press, 1989, pp. 227–282; Output Measurement in the Services Sector, Chicago, IL, University of Chicago Press, 1992, pp. 303–338) to estimate the monetary value of the human capital stock for New Zealand. Based on data from the New Zealand Census of Population, we find that the country's working human capital grew by half between 1981 and 2001, mostly due to the rise in employment level. This stock of human capital was also well over double that of physical capital in all the census years studied.

year: 2006

title: Ngā Pakanga mō Wāhi Tapu: Battles over sacred places

authors: Joseph, Robert

abstract: Wāhi tapu are the sacred places of Māori in Aotearoa New Zealand. All cultures have sacred sites such as cemeteries, significant battlefields, and places of spiritual significance. Standout examples internationally include the ‘Weeping Wall’ in the Holy Land, Stonehenge in Britain, Maraeātea in the Pacific, and Intihuatana at Macchu Picchu in Peru. But unlike these sites, wāhi tapu are rarely a visible structure but rather a site or area within the landscape with values so significant that restrictions are warranted. In law, wāhi tapu are defined as a ‘place of special significance according to tikanga Māori’
 and ‘a place sacred to Māori in the traditional, spiritual, religious, ritual, or mythological sense’.
As the aphorism above emphasises, Māori historically were willing to die for land (and for women of course!), and wāhi tapu are the most sacred of places. Many battles have been fought over actual or proposed transgressions of their sacredness. In earlier years, blood was shed and men did die; today battles tend to occur in the Environment Court, but are just as passionate. Recent decades have seen conflicts where wāhi tapu were threatened by new highways, railroads, airports, prisons, residential and commercial developments, wind farms, power stations and waste dumps.
In this chapter, I discuss a number of the battles that have been fought over the development or preservation of wāhi tapu from first European contact up until the present time. I highlight the growing legal recognition of tikanga Māori in relation to these sacred landscapes, and conclude with a proposed pragmatic solution for all New Zealanders when negotiating developments over wāhi tapu. Having a
background in law and tribal affiliations, I discuss these tensions from both legal and kaupapa Māori perspectives.

text: Ngā Pakanga mō Wāhi Tapu: Battles over sacred places Wāhi tapu are the sacred places of Māori in Aotearoa New Zealand. All cultures have sacred sites such as cemeteries, significant battlefields, and places of spiritual significance. Standout examples internationally include the ‘Weeping Wall’ in the Holy Land, Stonehenge in Britain, Maraeātea in the Pacific, and Intihuatana at Macchu Picchu in Peru. But unlike these sites, wāhi tapu are rarely a visible structure but rather a site or area within the landscape with values so significant that restrictions are warranted. In law, wāhi tapu are defined as a ‘place of special significance according to tikanga Māori’
 and ‘a place sacred to Māori in the traditional, spiritual, religious, ritual, or mythological sense’.
As the aphorism above emphasises, Māori historically were willing to die for land (and for women of course!), and wāhi tapu are the most sacred of places. Many battles have been fought over actual or proposed transgressions of their sacredness. In earlier years, blood was shed and men did die; today battles tend to occur in the Environment Court, but are just as passionate. Recent decades have seen conflicts where wāhi tapu were threatened by new highways, railroads, airports, prisons, residential and commercial developments, wind farms, power stations and waste dumps.
In this chapter, I discuss a number of the battles that have been fought over the development or preservation of wāhi tapu from first European contact up until the present time. I highlight the growing legal recognition of tikanga Māori in relation to these sacred landscapes, and conclude with a proposed pragmatic solution for all New Zealanders when negotiating developments over wāhi tapu. Having a
background in law and tribal affiliations, I discuss these tensions from both legal and kaupapa Māori perspectives.

year: 2011