Effect of modified atmosphere on storage life of purple passionfruit and red tamarillo : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Horticultural Science at Massey University

This study investigates methods to improve storage life of purple passionfruit (Passiflora edulis Sims) and tamarillo (Cyphomandra betacea (Cav.) Sendt). For passionfruit, the main problem for export and storage is shrivelling whereas for tamarillo the quality of the stem is a key factor in export standards. Eating quality of passionfruit was best described by the titratable acidity (TA) and the soluble solids content (SSC) with the optimal eating flavour found at an SSC/TA ratio between 10-11. Wax coating, ethylene scavenging, and modified atmosphere packaging (MAP) were assessed as tools to improve storage life. MAP with varying oxygen transmission rates (OTR at 5°C; 854, 1437, 2347 and 3089 ml m-2 day-1) were compared to the standard packaging in a cardboard box during storage at the commercial temperature of 8°C. Fruit quality was measured after 20, 28, and 42 days of storage with and without seven days of shelf life at 20°C in the same packaging as during storage. Waxing did not improve the quality of the fruit. MAP prevented shrivelling but in the packaging with lower OTR (854 - 1437 ml m-2 day-1) unacceptable external defects developed. Fruit quality in the packaging with the higher OTR (2347 - 3089 ml m-2 day-1) was similar except for the development of off-flavours in the packaging with an OTR of 2347 ml m-2 day-1 during shelf life possibly due to the high ethylene accumulation since the addition of an ethylene scavenger in a second trial eliminated the off-flavour development. The highest OTR MAP is the best option for long term storage. The second highest OTR MAP could be used providing an ethylene scavenger is added. To extend the storage life of tamarillo, two MAP options (OTR at 5°C; 1437 and 3089 ml m-2 day-1) were compared to the standard packaging in a cardboard box with polyliner as well as the effect of adding clove oil releasing sachets. All fruit were stored at 4°C for 56 days and fruit and stem quality was measured fortnightly with and without three days of shelf life at 20°C. MAP delayed the development of stem yellowing, which was related to chlorophyll degradation, but did not improve fruit quality and increased stem blackening and bleeding in the locule, especially when clove oil was added. Blackening was related to polyphenol oxidase activity and was aggravated by clove oil or by injury (e.g. disruption of cellular membranes) due to lower O2, higher CO2 and higher ethylene concentrations. Thus, for the two films tested, MAP with or without the addition of clove oil offered no advantages over conventional air storage

Bioenergy Development in Thailand: Challenges and Strategies

AbstractIn recognition of concerns about the security of energy supply and climate change, the Thai government has developed Alternative Energy Development Plan for the period 2012–2021. Under this plan, the production of bio- ethanol and biodiesel in 2021 is expected to grow significantly. This growth will add more pressures on water and land requirements for growing energy crops. This is likely to contribute to worsening the security of water and food supply. This paper, therefore, provides an overview of the bioenergy development and current policies in Thailand with a view to identify the challenges faced by the development of bioenergy. A review of the bioenergy policies reveals that the existing policies have been exclusively focus on energy perspective and largely ignore the significance of the implications arising from the interdependencies between energy, water and food. There is a lack of understanding of the interrelationships between bioenergy, water and food policy interactions. The lack of such understanding is likely to pose several challenges including food or fuel dilemma, security of water supply and issues surrounding land use for biofuel production. This paper further emphasizes the need to develop an integrated framework for developing an understanding of the relationships between energy, water and land

Doctor of Philosophy

dissertationAsphaltenes are one of the component fractions in crude oil and can destabilize due to a change of pressure, temperature, or composition. Destabilized asphaltenes can precipitate and deposit, causing numerous problems and challenges during oil production and processing such as plugging, fouling, and emulsion stability. Thermodynamic models were previously developed to investigate and predict the phase behavior of asphaltenes using experimental data that assumed the destabilized asphaltenes reach their equilibrium state immediately after changing system conditions. However, asphaltene precipitation has previously been shown to be a slow aggregation process suggesting that the previous thermodynamic models might be inaccurate and misrepresent the behavior of asphaltenes. Reversibility is a requirement for the application of equilibrium thermodynamics to predict the phase behavior of mixtures. In this work, asphaltene precipitation was found to be a reversible process, and the cause of the partial reversibility conclusion in previous work was discovered to be a neglected slow aggregation process. This finding reinforces the importance of a slow aggregation process as it shows that considering the kinetics can significantly alter the conclusions. The aggregation rates of asphaltenes have also previously been investigated and found that the aggregation rates of asphaltenes depend on thermodynamic driving forces. This study shows that asphaltene aggregation and deposition highly correlate with thermodynamic driving forces, but the deposit growth was governed by diffusion limitations. This investigation reveals that thermodynamic properties can directly investigate the asphaltene behavior, and the diffusion limitation finding can lead to developing a new and more accurate deposition model. In addition, for the first time, the presence of inorganic solids was observed to increase the rate of asphaltene precipitation. A model was developed to quantify the rate of asphaltene precipitation under different process conditions. This investigation leads to a clearer understanding of the complex asphaltene aggregation process that occurs in real and heterogeneous systems. The usages of inorganic solids as nucleation sites to remove unstable asphaltenes and decrease the asphaltene problems during the production are potentially possible. The findings from this dissertation emphasize the essentials of precipitation kinetics and provide ideas to decreases the asphaltene problems and understanding the behavior of asphaltenes using the thermodynamic properties

PhD

dissertationNew methodology was developed to study bone microradiographs on a television image analyzing system, The optimum exposure time for producing microradiographs of 100 micron ground bone sections with sufficient contrast for the quantitative television microscope was determined. The microradiographs were standardized by using a step wedge made from aluminum foil. The microradiographs produced from a bone section (cross-section of lumbar vertebra) ground in several steps from 120 to 70 microns were found to give the same morphometric measurements. With the use of the image editor light pen of the image analyzer (QTM-720) to separate cortical and trabecular bone, complete information of the bone was obtained from the serial cross-sections. The variations of the measurements were detected from one end of the bone to the other leading to the reconstruction of the bone and to a determination of the accuracy of selecting samples for a specific morphometric study. The first lumbar vertebra and the proximal femur from each of 14 beagles were chosen to study changes in morphometric parameters as a function of age and sex. In the cross-sections of the ventral vertebra the maxima of trabecular bone area, percent bone and surface area per volume of tissue were detected at the end potions; these values decreased gradually and had a minimum at the middle part of the main vertebral body. The specific bone surface was more or less uniform within the main vertebral body but dropped abruptly as it reached the end portions where the epiphysis was located. In contrast there were no significant changes in the measurements among sections in the dorsal vertebra; greater trabecular width and higher percent bone were characteristics of this portion. In the cross-sections of the proximal femur the head region had greater trabecular width and higher percent bone than the non-head portion; percent bone was nearly uniform within the head portion but decreased gradually from the proximal end of the non-head portion down into the shaft. The morphometric parameters and dimensions of the bones were presumed to be a function in response to stresses; the variations were observed in beagles of the same age and sex and to a higher degree in the proximal femur than in the vertebra. Bone is rapidly developing in the three month old beagles and could not be compared with the adults. No specific differences in measurements were detected in beagles from 17 months to 11 years, male and female. There was no indication of osteoporosis. Cross-sections of the vertebra and proximal femur showed isotropic orientation of the trabeculae while in the longitudinal sections anisotropic trabeculae were detected in all portions of the vertebra and the non-head portion of the proximal femur. The isotropic structures were preferred for study since the three dimensional measurements could be calculated from a universal k value of 4 over pi whereas in anisotropic structures the k value could not be given directly, since the anisotropy varied from section to section and within different regions of the same section

Electricity industry reforms in Thailand : a comprehensive review

University of Technology, Sydney. Faculty of Engineering and Information Technology.Prompted by the concerns about the poor performance of the Thai electricity industry, the Thai government initiated, in the year 1992, a process of reform of the electricity industry. The reform, argued its proponents, would improve industry performance and provide economy-wide benefits. A comprehensive analysis developed in this research - employing a combination of analytical methodologies, including historical analysis, Data Envelopment Analysis (DEA), input-output analysis, and inferential analysis - has demonstrated that electricity reform has largely failed to achieve its objectives. For example, electricity reform has neither noticeably improved industry performance nor provided any appreciable benefits to the wider economy. This is because the reform program has tended to focus almost exclusively on industry privatization; the accompanying structural and regulatory changes have been limited to the extent that they support privatization. Further, it appears that only financial dimension of reform has received attention and that other dimensions (i.e., social and environmental) have largely been ignored. This narrow focus, this research argues, has its roots in several internal and external developments and influences, for example, pressures from the international financial institutions, major economic crises, political factors , institutions, and other interests. This narrowly-focused reform program, therefore, could not produce desirable outcomes as was expected. This research identifies some remedies that might be needed in order to improve the efficacy of the present reform program. For this purpose, three alternative reform models (PDP, IPP, and GE) are proposed and their consequences analyzed, through the application of DEA and input-output analysis, for the period 2010-2020. These analyses suggest that the GE scenario, which promotes Small Power Producers (SPPs) generating electricity from renewable sources and envisages import of hydroelectricity from the neighbouring countries, would be an attractive option for Thailand. This is due mainly to its ability to provide a balanced redress for energy, environmental, economic, social, and industry performance objectives. Whether or not such redress will eventuate will however depend - to a large extent - on the efficacy of the 'new' institutional arrangements including industry structure, ownership and regulation. This argument is based on the premise that the existing institutional arrangements are deficient and hence unsuitable to provide a balanced redress referred to above. Against this backdrop, this research proposes a n1odified reform approach for the Thai electricity industry. The key features of the proposed reform approach include a fill unbundling of the generation and transmission functions of Electricity Generating Authority of Thailand (EGAT), allowing the Independent Power Producers (IPPs) to also establish small-scale power plants, promoting increased participation by SPPs and Very Small Power Producers (VSPPs), disaggregating the Provincial Electricity Authority (PEA) into four regional distributors, and ensuring transparency and autonomy of the regulatory body. This research also proposes some strategies that could be adopted in order to overcome the challenges that are likely to emerge when the proposed reform model is implemented. The proposed reform approach, this research contends, will provide a robust pathway to meet the future electricity needs of Thailand. This is due to the fact that it accords with the economic, environmental, social, and political realities in Thailand. Further, it is contended that this research has made a valuable contribution in terms of developing policy insights that should provide a sound basis for furthering the reform of the Thai electricity industry - an issue of immense contemporary policy significance for Thailand

Quality Evaluation of Deep-Fat Fried Peas

Dehydration is perhaps the oldest method of preserving fruits and vegetables. However, it is still an important method of preservation, During World War II, efforts were geared to investigate the possibilities of such newer dehydrated foods as powdered eggs, tomatoes, and potato granules. Since then many new products are flooding the market every year. The use of dehydrated products has increased primarily because they usually require leas space and have longer shelf life, and at the same time they have much more concentrated nutritive value than fresh, canned, or frozen foods, Hence, they can easily be adopted for military rations. Because of their ease of handling and transportation they may serve as a snack and picnic food

The Study of Hom-rong Ta-yoi Diaw Song

This research presents the study of Hom-rong Ta-yoi diaw song, which had objectives 1) to study thehistory of Hom-rong Ta-yoi diaw song and 2) to analyze the components of Hom-rong Ta-yoi diaw song.As a result, the findings can be summarized as followed;Part 1: The study of the history of Hom-rong Ta-yoi diaw songKru Samran Kerdphol was a resident of Ayutthaya province. He started study Thai music with KruJamrat Kerdphol and Kru Sangwian Kerdphol. Later, he studied with Kru Petch Jannad, Kru TiebKonglaithong, Kru Chad Sunthornwatin, Kru Chor Sunthornwatin, and Kru Ard Sunthorn. Kru SamranKerdphol had composed Hom-rong Ta-yoi diaw song on 1996. Since he discovered that Grao overturewas composed, he composed Hom-rong Ta-yoi diaw song to performed against Grao overture and passedon to his students in the Phatthayarat Piphat ensemble to perform for Her Royal Highness PrincessMahachakri Sirindhorn in 1999. After that, it was passed on to the students in College of Music, MahidolUniversity and performed in many important events.Part 2: The analysis of the components of Hom-rong Ta-yoi diaw songHom-rong Ta-yoi diaw song was a Thai verse overture, which had both slow and middle speed beatsand used Song Mai rhythm. It was suitable to be performed by double Piphat ensemble. In addition, therewere many performing techniques including whole band Thirty-second notes, Sixteen note melody, roundmelody, and solo. This song had a complete and thorough performance pattern. Therefore, the potentialof the performer could be fully exposed.Kru Samran Kerdphol used the structure of Ta-yoi diaw song to compose Hom-rong Ta-yoi diawsong with 4 scales, which were C scale, D scale, F scale, and G scale. The scale that occurred the mostwas G scale with 164 paragraphs. The followings were C scale and F scale with 52 and 15 paragraphs,respectively. In addition, the least was D scale with 6 paragraphs. Moreover, improvising the melody ofRanad ek using the significant notes of main melody and constantly using passing notes created harmonymelody. Although the solo of each instrument was performed in a short duration only once, theuniqueness of each instrument was still presented completely.Key words: Hom-rong, Ta-yoi diaw song, history, component

Oversampling technique in student performance classification from engineering course

The first year of an engineering student was important to take proper academic planning. All subjects in the first year were essential for an engineering basis. Student performance prediction helped academics improve their performance better. Students checked performance by themselves. If they were aware that their performance are low, then they could make some improvement for their better performance. This research focused on combining the oversampling minority class data with various kinds of classifier models. Oversampling techniques were SMOTE, Borderline-SMOTE, SVMSMOTE, and ADASYN and four classifiers were applied using MLP, gradient boosting, AdaBoost and random forest in this research. The results represented that Borderline-SMOTE gave the best result for minority class prediction with several classifiers

Learn English or die: The effects of digital games on interaction and willingness to communicate in a foreign language

In recent years there has been a lot of interest in the potential role of digital games in language education. Playing digital games is said to be motivating to students and to benefit the development of social skills, such as collaboration, and metacognitive skills such as planning and organisation. An important potential benefit is also that digital games encourage the use of the target language in a non-threatening environment. Willingness to communicate has been shown to affect second language acquisition in a number of ways and it is therefore important to investigate if there is a connection between playing games and learners’ interaction in the target language. In this article we report on the results of a pilot study that investigated the effects of playing an online multiplayer game on the quantity and quality of second language interaction in the game and on participants’ willingness to communicate in the target language. We will show that digital games can indeed affect second language interaction patterns and contribute to second language acquisition, but that this depends, like in all other teaching and learning environments, on careful pedagogic planning of the activity