title: Bounded Eigenvalues of Fully Clamped and Completely Free Rectangular Plates

authors: Mochida, Yusuke

subjects: vibration

abstract: Exact solution to the vibration of rectangular plates is available only for plates with two opposite edges subject to simply supported conditions. Otherwise, they are analysed by using approximate methods. There are several approximate methods to conduct a vibration analysis, such as the Rayleigh-Ritz method, the Finite Element Method, the Finite Difference Method, and the Superposition Method. The Rayleigh-Ritz method and the finite element method give upper bound results for the natural frequencies of plates. However, there is a disadvantage in using this method in that the error due to discretisation cannot be calculated easily. Therefore, it would be good to find a suitable method that gives lower bound results for the natural frequencies to complement the results from the Rayleigh-Ritz method. The superposition method is also a convenient and efficient method but it gives lower bound solution only in some cases. Whether it gives upper bound or lower bound results for the natural frequencies depends on the boundary conditions. It is also known that the finite difference method always gives lower bound results. This thesis presents bounded eigenvalues, which are dimensionless form of natural frequencies, calculated using the superposition method and the finite difference method. All computations were done using the MATLAB software package. The convergence tests show that the superposition method gives a lower bound for the eigenvalues of fully clamped plates, and an upper bound for the completely free plates. It is also shown that the finite difference method gives a lower bound for the eigenvalues of completely free plates. Finally, the upper bounds and lower bounds for the eigenvalues of fully clamped and completely free plates are given.

text: Bounded Eigenvalues of Fully Clamped and Completely Free Rectangular Plates Exact solution to the vibration of rectangular plates is available only for plates with two opposite edges subject to simply supported conditions. Otherwise, they are analysed by using approximate methods. There are several approximate methods to conduct a vibration analysis, such as the Rayleigh-Ritz method, the Finite Element Method, the Finite Difference Method, and the Superposition Method. The Rayleigh-Ritz method and the finite element method give upper bound results for the natural frequencies of plates. However, there is a disadvantage in using this method in that the error due to discretisation cannot be calculated easily. Therefore, it would be good to find a suitable method that gives lower bound results for the natural frequencies to complement the results from the Rayleigh-Ritz method. The superposition method is also a convenient and efficient method but it gives lower bound solution only in some cases. Whether it gives upper bound or lower bound results for the natural frequencies depends on the boundary conditions. It is also known that the finite difference method always gives lower bound results. This thesis presents bounded eigenvalues, which are dimensionless form of natural frequencies, calculated using the superposition method and the finite difference method. All computations were done using the MATLAB software package. The convergence tests show that the superposition method gives a lower bound for the eigenvalues of fully clamped plates, and an upper bound for the completely free plates. It is also shown that the finite difference method gives a lower bound for the eigenvalues of completely free plates. Finally, the upper bounds and lower bounds for the eigenvalues of fully clamped and completely free plates are given.

year: 2007

title: Enhancement of "flavours" through enzymatic release of glutamate

authors: Juwono, Joshua

abstract: The sensory characteristics of food, in particular the flavours of food, play a very crucial role in the food industry. It is often what consumers associate most from food, and it is therefore crucial for food manufacturers like The Tatua Co-operative Dairy Company to produce flavour ingredients that are unique and of the highest quality.  
The Dairy Flavour Ingredients Business Unit at Tatua produces a range of dairy flavour ingredients including Butter, Cream and Milk, and Cheese Flavours. Tatua exports most of their flavour products worldwide to various food manufacturers, enhancing the flavour of the products that such manufacturers produce. Umami or savouriness is one of the five primary tastes. It is one of the most important flavour characteristic in dairy flavourings. In particular, umami is most needed in many of the different cheese flavourings produced by Tatua.  
This project focuses on optimising the release of glutamate from casein. Liberated glutamate with a commercial name HCP337 is used as a flavour enhancer, increasing the umami of the dairy flavourings that Tatua makes. Alternatively, the addition of monosodium glutamate (MSG) can also increase the umami of the flavours that Tatua makes, however this is not possible due to a couple of reasons: MSG has a negative reputation in the consumers’ mind, as many believe consumption of MSG can cause negative health effects; another reason is that addition of MSG would prevent Tatua from labelling their products as “natural”. Thus, the glutamate used for Tatua’s flavour ingredients is derived from the proteolysis of casein.  
Currently, the problem is that very little free glutamate is present in the HCP337 product even after a very long proteolysis. Therefore, the purpose of this project is to comprehensively examine the biochemistry of glutamate release in order to find the optimum proteolysis condition and use this knowledge to optimise the current process, increasing glutamate release. 
Three techniques were developed over the initial part of the study to quantify glutamate, glutamine, and pyroglutamic acid. A thorough set of samples from the HCP337 production process were then characterised. We found that indeed there was low glutamate content in the HCP337 product, and there was pyroglutamic acid in significant amounts. Stability tests of both glutamate and glutamine showed that glutamate is stable and not affected by the processing conditions. On the other hand, glutamine is very unstable and converted into pyroglutamic acid spontaneously under the processing conditions.  
With this information, various tests were performed with the focus of maximising glutamate yield from casein. These tests included: testing the proteolytic capacity of new and different enzymes at differing pH values with the hope of finding a better and more suitable enzyme at liberating glutamate from casein, the use of different acidifying agents in the HCP337 production process, and the screening of glutaminase activity within the new enzymes. The presence of glutaminase may further increase the glutamate yield, as glutaminase will convert the free glutamine released into glutamate instead of it spontaneously forming pyroglutamic acid. 
In summary, this study demonstrated that the current HCP337 production process is not designed to optimally release glutamate from casein. Altering the pH and enzyme combinations during hydrolysis did not appear to be effective strategies to increase glutamate release from casein. More tests on more enzyme should be conducted in the future in order to find enzymes that are most effective at releasing glutamate under the appropriate production process.

text: Enhancement of "flavours" through enzymatic release of glutamate The sensory characteristics of food, in particular the flavours of food, play a very crucial role in the food industry. It is often what consumers associate most from food, and it is therefore crucial for food manufacturers like The Tatua Co-operative Dairy Company to produce flavour ingredients that are unique and of the highest quality.  
The Dairy Flavour Ingredients Business Unit at Tatua produces a range of dairy flavour ingredients including Butter, Cream and Milk, and Cheese Flavours. Tatua exports most of their flavour products worldwide to various food manufacturers, enhancing the flavour of the products that such manufacturers produce. Umami or savouriness is one of the five primary tastes. It is one of the most important flavour characteristic in dairy flavourings. In particular, umami is most needed in many of the different cheese flavourings produced by Tatua.  
This project focuses on optimising the release of glutamate from casein. Liberated glutamate with a commercial name HCP337 is used as a flavour enhancer, increasing the umami of the dairy flavourings that Tatua makes. Alternatively, the addition of monosodium glutamate (MSG) can also increase the umami of the flavours that Tatua makes, however this is not possible due to a couple of reasons: MSG has a negative reputation in the consumers’ mind, as many believe consumption of MSG can cause negative health effects; another reason is that addition of MSG would prevent Tatua from labelling their products as “natural”. Thus, the glutamate used for Tatua’s flavour ingredients is derived from the proteolysis of casein.  
Currently, the problem is that very little free glutamate is present in the HCP337 product even after a very long proteolysis. Therefore, the purpose of this project is to comprehensively examine the biochemistry of glutamate release in order to find the optimum proteolysis condition and use this knowledge to optimise the current process, increasing glutamate release. 
Three techniques were developed over the initial part of the study to quantify glutamate, glutamine, and pyroglutamic acid. A thorough set of samples from the HCP337 production process were then characterised. We found that indeed there was low glutamate content in the HCP337 product, and there was pyroglutamic acid in significant amounts. Stability tests of both glutamate and glutamine showed that glutamate is stable and not affected by the processing conditions. On the other hand, glutamine is very unstable and converted into pyroglutamic acid spontaneously under the processing conditions.  
With this information, various tests were performed with the focus of maximising glutamate yield from casein. These tests included: testing the proteolytic capacity of new and different enzymes at differing pH values with the hope of finding a better and more suitable enzyme at liberating glutamate from casein, the use of different acidifying agents in the HCP337 production process, and the screening of glutaminase activity within the new enzymes. The presence of glutaminase may further increase the glutamate yield, as glutaminase will convert the free glutamine released into glutamate instead of it spontaneously forming pyroglutamic acid. 
In summary, this study demonstrated that the current HCP337 production process is not designed to optimally release glutamate from casein. Altering the pH and enzyme combinations during hydrolysis did not appear to be effective strategies to increase glutamate release from casein. More tests on more enzyme should be conducted in the future in order to find enzymes that are most effective at releasing glutamate under the appropriate production process.

year: 2016

title: Māori provisions in plans: Mana whenua, mauri of water, and wahi tapu

authors: Kennedy, Nathan

subjects: New Zealand

abstract: The intention  of  this  document  is  to  allow  those  using  Ngā  Mahi:  Kaupapa  Māori Outcomes an  Indicators Kete (Jefferies and Kennedy, 2009, PUCM Māori Report 2) to view a range of examples of Māori provisions within statutory planning documents against plans being evaluated. The extracts in this Report 3 on Māori Provisions in Plans relate to the three tikanga in the Ngā Mahi report: Mana Whenua, Mauri (relating to water), and Wähi Tapu. It is intended that as we develop new kete (containing worksheets and user guides) and thereby expand Ngā Mahi, this current report will be revised to include plan provisions relating to additional tikanga.

text: Māori provisions in plans: Mana whenua, mauri of water, and wahi tapu The intention  of  this  document  is  to  allow  those  using  Ngā  Mahi:  Kaupapa  Māori Outcomes an  Indicators Kete (Jefferies and Kennedy, 2009, PUCM Māori Report 2) to view a range of examples of Māori provisions within statutory planning documents against plans being evaluated. The extracts in this Report 3 on Māori Provisions in Plans relate to the three tikanga in the Ngā Mahi report: Mana Whenua, Mauri (relating to water), and Wähi Tapu. It is intended that as we develop new kete (containing worksheets and user guides) and thereby expand Ngā Mahi, this current report will be revised to include plan provisions relating to additional tikanga.

year: 2008-07-31