Master of Science / Department of Grain Science and Industry / Ekramul Haque / The effect of enzyme in temper water on wheat milling performance and flour quality was studied. Five independent variables, enzyme concentration, incubation time, incubation temperature, tempered wheat moisture content, and tempering water pH, were studied. An enzyme cocktail consisting of cellulase, xylanase, and pectinase was used at 5 different concentrations. A single pure variety of hard red winter wheat was tempered under defined conditions following an RSM central composite design which required 33 tests including 7 replicates. Each treatment had 5 levels: high, medium high, medium, medium low, and low. After tempering, the physical characteristics of the wheat kernel were determined by using the Single Kernel Characterization System. An experimental laboratory mill (Ross Mill) was used to mill wheat into flour. Thirteen streams of flour, and additional streams of bran, shorts, red dog, and germ were obtained. Product yield, protein, ash, and flour color were evaluated. The data were analyzed and compared using the software SAS and RSM Plus. The data showed that incubation time was the only significant factor affecting the tempered wheat hardness (p<0.05). The treatments affected the flour yield from the break rolls more than that from the reduction rolls. However, a maximum point for flour yield was not found. The relationship between treatments and flour yield was established with a prediction model equation. Also, the enzyme effect on the dough properties and bread making were investigated. The treatments did not affect the optimum water absorption for the flours. However, enzyme treated flours showed shorter mixing times. Regardless of the differences in mixing times, the specific loaf volumes were not significantly different for the all treatments. Bread baked from the flour milled from enzyme treated wheat did not show a positive effect on bread staling.

Master of Science / Department of Grain Science and Industry / Finlay I. MacRitchie / Ozone, a triatomic form of oxygen with a Generally Recognized As Safe (GRAS) status from the U. S. Food and Drug Administration, is a strong antimicrobial and sanitizing agent with numerous potential applications in the food industry. One of them is the improvement of wheat flour baking qualities, by replacement of the actual chlorination treatment. Following recent developments realized by the company Goemar (France) which invented and patented an ozone treatment device for wheat grain and a method for making flour from ozone-treated grains, this study aims to determine the effect of ozone treatment on wheat grain and on wheat flour, and to compare them. Three different ozone concentrations with different application times rendering three quantities of absorbed ozone have been investigated. Rheological, physicochemical and baking properties of soft wheat flours stemming from both treatments were evaluated and compared to untreated flour. Results were overall significant and showed that the treatment of flour gives more marked results than the treatment on grain for retention capacity in sucrose and volume of cakes but decreases the [alpha]-amylase activity. On the other hand, action of ozone on grain augments the maximum viscosity of the flour. Bread volume was found to be increased by both treatments in similar proportions. The treatments were also analyzed in particular and showed specific characteristics. A single treatment has not been determined to enhance all characteristics of the flour. Hence, the modification of precise features of the flour has to be related to a specific treatment.

Doctor of Philosophy / Food Science Institute / Finlay I. MacRitchie / Ozonation was studied as an alternative to chlorination for cake flour. Ozone treatment in a wooden tumbler at room temperature was conducted. Unchlorinated flour was treated with ozone at the rate of 0.06 L/min for 10 and 36 min using 5 lb of flour. Ozonation of cake flour decreased pH and increased the lightness (L value) of flour. Baking studies using a high-ratio white layer cake formulation showed that the volume of cakes significantly increased (p< 0.05) as ozonation time increased and cakes were softer than those made with chlorinated or control flours. The cell brightness and number of cells measured by image analysis (C-Cell) of cakes from ozone treated flour for 36 min exhibited similar values to those from chlorinated flour. Cakes made from flours after lipid extraction and after lipid extraction plus ozonation had low volume, indicating that lipids play a role in cake performance. Identification of volatile compounds that contribute to the odor of ozone treated flour was conducted. Volatile compounds of chlorinated, unchlorinated, defatted control, and ozonated defatted flours were analyzed using a purge and trap instrument and GC-MS. Aldehydes, alcohols, hydrocarbons and other compounds were found in unchlorinated and chlorinated flours while the volatile compounds present in ozone treated flours were mainly aldehydes and ketones. A rapid reduction in volatile compounds was detected when ozone treated flours were stored uncovered in a fume hood. Ozonation of defatted soft wheat flour produced less volatile aldehydes than ozone treated whole flour. The optimum temperature and time for ozone treatment in a metal tumbler using a response surface methodology design was studied. Time (5, 15, and 25 min) and temperature (25, 35 and 45 [degrees]C) was used with three response parameters. The optimum ozonation time was about 8 to 11 min with the temperature range between 36 and 46 [degrees]C. Ozone treatment for 5 to 25 min at room temperature showed an increase in unextractable polymeric protein, indicating a shift of protein to a higher molecular weight. Increase in Mixograph peak time, peak viscosity, and water retention capacity were observed as ozonation time increased. The ozone treatment did not affect the transition temperature and enthalpy change of the flour samples.

Doctor of Philosophy / Department of Hotel, Restaurant, Institution Management and Dietetics / Elizabeth B. Barrett / This study examined the relationships among restaurant managers' attitudes, subjective norms, and perceived behavioral controls, using the Theory of Planned Behavior, that cause them to support or not support food safety training for their employees. The goal of this study was to investigate the facts that affect restaurant managers' willingness to support food safety training for their employees. Based on the results of the elicitation study, a pilot test focus group, and a pilot study, an 85 question instrument, that measured eight constructs and demographic information was developed. The instrument was administered via telephone, but response data was input using an online format. Data was entered electronically as it was collected. A total of 266 managers responded, but due to incomplete and missing data, 237 responses were usable. The final overall response rate was 17.9%. Results determined that overall intention to offer food safety training to employees was high. Restaurant managers had a positive attitude about food safety, placed importance on the beliefs of individuals they consider important, and felt they were in control about offering food safety training to their employees. Certified managers had more positive attitudes about offering food safety training and placed more emphasis on those individuals whom they considered to be important in their lives (subjective norms), but also perceived they had less control about offering food safety training to their employees. Most importantly, those managers who were certified had a higher intention to train employees than managers who did not have food safety certification. When comparing behavioral, normative, and control beliefs between chain and independent restaurant managers, only behavioral (specific attitudes) and normative beliefs (specific individuals whom they considered important) differed. In the multiple regression analysis exploring the prediction of behavior based on the respondents attitudes, subjective norms, and perceived behavioral controls, the model was significant (F=139.932, p [equal to or less than] .000) (Table 5.2). The significant independent variables in the model were the attitude mean composite score (Beta=-0.106, p [equal to or less than] .038) and the subjective mean composite score (Beta=0.727, p [equal to or less than] .000). Perception of control was not significant. Three multiple regression models were used to examine the relationships between the attitudes, subjective norms, and perceived behavioral controls as dependent variables and the factors for their indirect measures as independent variables. Of the three simple linear regression models, only two were significant. The regression of the behavioral belief factors on attitude composite score (Hypothesis 4) (F=16.714, p [equal to or less than] .000) and the regression of normative belief factors on the subjective norm composite score (F=11.896, p [equal to or less than] .000) were significant. The regression of control beliefs on perceived behavioral control showed no significance.

Master of Science / Food Science Institute / Fadi M. Aramouni / Ohmic heating for the food industry consists of using electrical energy to heat foods as a method of preservation, which can in turn be used for microbial inactivation or several other processes such as pasteurization, extraction, dehydration, blanching or thawing. Few studies have been conducted on the usefulness of this environmentally friendly processing technique. Due to the lack of sufficient information on research into ohmic heating for the food industry, a few of the published studies are discussed here in detail. This report also focuses on self-conducted research using ohmic heating to determine its effect on Lactobacillus acidophilus inactivation versus conventional heating. Lactobacillus acidophilus was inoculated into MRS broth and incubated for 24 hours. The sample was then inoculated into sterile buffer at a dilution rate of 1:100. Samples of the diluted culture were subjected to either low voltage (18 V) or conventional heating (300°C) over a hotplate stirrer. Temperature was monitored on test and control samples to achieve an endpoint of 90°C. Samples were taken at regular intervals, plated onto MRS agar and incubated for 72 hours at 35°C to compare plate count expressed as colony forming units per milliliter (cfu/mL). Temperature was uniform throughout the ohmically heated sample and reached the endpoint more quickly than the conventionally heated sample, which also had cold spots. The total plate count at the end of the experiment was less for the ohmically heated sample versus the conventionally heated sample. Ohmic heating was more effective in inactivation of Lactobacillus acidophilus than conventional heating, most likely due to the more rapid and uniform heating of the sample, and possible electroporation of the cells.

The wireless sensor is a micro-embedded device with weak data processing capability and small storage space. These nodes need to complete complex jobs, including data monitoring, acquisition and conversion, and data processing. Energy efficiency should be considered as one of the important aspects of the Wireless Sensor Network (WSN) throughout architecture and protocol design. At the same time, supporting Quality of Service (QoS) in WSNs is a research field, because the time-sensitive and important information is expected for the transmitting to to the sink node immediately. The thesis is supported by the projects entitled “The information and control system for preventing forest fires”, and “The Erhai information management system”, funded by the Chinese Government. Energy consumption and QoS are two main objectives of the projects. The thesis discusses the two aspects in route and Media Access Control (MAC). For energy efficiency, the research is based on Low Energy Adaptive Clustering Hierarchy (LEACH) protocol. LEACH is a benchmark clustering routing protocol which imposes upon cluster heads to complete a lot of aggregation and relay of messages to the base-station. However, there are limitations in LEACH. LEACH does not suit a wide area in clustering strategy and multi-hop routing. Moreover, routing protocols only focus on one factor, combining the clustering strategy and multi-hop routing mechanism were not considered in routing protocol for performance of network. QoS is supported by the MAC and routing protocol. Sensor MAC(S-MAC) makes the use of the periodically monitoring / sleeping mechanism, as well as collision and crosstalk avoidance mechanism. The mechanism reduces energy costs. Meanwhile, it supports good scalability and avoids the collision. However, the protocols do not take the differentiated services. For supporting QoS,A new route protocol needs to be designed and realized on embed platforms, which has WIFI mode and a Linux operation system to apply on the actual system. This research project was conducted as following the steps: A new protocol called RBLEACH is proposed to solve cluster on a widely scale based on LEACH. The area is divided into a few areas, where LEACH is improved to alter the selecting function in each area. RBLEACH creates routes selected by using a new algorithm to optimize the performance of the network. A new clustering method that has been developed to use several factors is PS-ACO-LEACH. The factors include the residual energy of the cluster head and Euclidean distances between cluster members and a cluster head. It can optimally solve fitness function and maintain a load balance in between the cluster head nodes, a cluster head and the base station. Based on the “Ant Colony” algorithm and transition of probability, a new routing protocol was created by “Pheromone” to find the optimal path of cluster heads to the base station. This protocol can reduce energy consumption of cluster heads and unbalanced energy consumption. Simulations prove that the improved protocol can enhance the performance of the network, including lifetime and energy conservation. Additionally, Multi Index Adaptive Routing Algorithm (MIA-QR) was designed based on network delay, packet loss rate and signal strength for QoS. The protocol is achieved by VC on an embedded Linux system. The MIA-QR is tested and verified by experiment and the protocol is to support QoS. Finally, an improved protocol (SMAC -SD) for wireless sensor networks is proposed, in order to solve the problem of S-MAC protocol that consider either service differentiation or ensure quality of service. According to service differentiation, SMAC-SD adopts an access mechanism based on different priorities including the adjustment of priority mechanisms of channel access probability, channel multi-request mechanisms and the configuring of waiting queues with different priorities and RTS backoff for different service, which makes the important service receive high channel access probability, ensuring the transmission quality of the important service. The simulation results show that the improved protocol is able to gain amount of important service and shortens the delay at the same time. Meanwhile, it improves the performance of the network effectively.

Image retrieval plays a major role in many image processing applications. However, a number of factors (e.g. rotation, non-uniform illumination, noise and lack of spatial information) can disrupt the outputs of image retrieval systems such that they cannot produce the desired results. In recent years, many researchers have introduced different approaches to overcome this problem. Colour-based CBIR (content-based image retrieval) and shape-based CBIR were the most commonly used techniques for obtaining image signatures. Although the colour histogram and shape descriptor have produced satisfactory results for certain applications, they still suffer many theoretical and practical problems. A prominent one among them is the well-known “curse of dimensionality “. In this research, a new Fuzzy Fusion-based Colour and Shape Signature (FFCSS) approach for integrating colour-only and shape-only features has been investigated to produce an effective image feature vector for database retrieval. The proposed technique is based on an optimised fuzzy colour scheme and robust shape descriptors. Experimental tests were carried out to check the behaviour of the FFCSS-based system, including sensitivity and robustness of the proposed signature of the sampled images, especially under varied conditions of, rotation, scaling, noise and light intensity. To further improve retrieval efficiency of the devised signature model, the target image repositories were clustered into several groups using the k-means clustering algorithm at system runtime, where the search begins at the centres of each cluster. The FFCSS-based approach has proven superior to other benchmarked classic CBIR methods, hence this research makes a substantial contribution towards corresponding theoretical and practical fronts.

Breast focal asymmetry is an important sign of early breast cancer and might be a developing masses or other underlying breast cancer. However, breast focal asymmetry is very difficult to recognise, even for the specialists of radiologists because focal asymmetries lack the boundary and consistent shape of masses and are similar to normal fibroglandular tissues. The computer-aided detection (CADe) for focal asymmetry is a novel research topic in the field of computer-aided detection of breast cancer. The detection of focal asymmetry has the significant value to save women’s live in the early stage of breast cancer. At present, there is only one existing dedicated detection solution for focal asymmetry, which was proposed in 2008. The aim of this research is to develop a novel dedicated computer-aided detection solution for focal asymmetry and overcome the weakness of the existing approach. The objectives of this research are to propose a novel solution for detecting focal asymmetry, a novel breast segmentation approach, a novel pectoral muscle detection approach and a dedicated focal asymmetry detection approach. The literature review of previous researches for focal asymmetry, asymmetric breast findings, breast segmentation and pectoral muscle detection have been extensively carried out. Based on the literature review, a range of hypotheses have been proposed for breast segmentation, pectoral muscle detection and focal asymmetry detection. Furthermore, a novel framework and three novel approaches have been proposed and developed in this research. Firstly, the automatic breast segmentation (ABS) approach was proposed to segment the skin-line of breast from mammographic images and preserve the nipple at the same time, a task which very few breast segmentation methods claimed. The experimental results showed that the ABS approach can adequately segment the breast skin-line and preserve the nipple if it is in profile. The proposed ABS approach is one of three existing breast segmentation approaches that can segment breast skin-line and preserve the nipple at the same time. Secondly, a novel approach for detecting pectoral muscle has been proposed to detect and remove pectoral muscle from the segmented breast areas. The experimental results showed that the proposed maximum intensity change (MIC) approach can detect pectoral muscle with high quality. Thirdly, the novel approach for detecting focal asymmetry has been proposed in this research and various features have been extracted to classify a suspicious region into the category of focal asymmetry or non-focal asymmetry. The experimental results indicated that the proposed detection approach can detect focal asymmetry with the 81.8% sensitivity and the 0.333 false positive regions per image. This research has proposed a novel framework and three novel approaches to build the computer-aided detection solution for focal asymmetry. This research overcomes the weakness of current approach for detecting focal asymmetry. The proposed detection approach is the second dedicated solution for detecting breast focal asymmetry in existence.

Creep deformation and failure in high temperature structures is a serious problem for industry and is becoming even more so under the current increasing pressures of power, economics and sustainability. Laboratory creep tests can be used in the description of creep damage behaviour; however, it’s usually expensive and time-consuming. Thus, the computer-based finite element (FE) technique is considered here for both time and economic efficiency. This project aims to develop an in-house FE software for creep damage analysis. A novel in-house FE software High Temperature Structural Integrity (HITSI) was developed through the use of Continuum Damage Mechanics (CDM) and finite element method (FEM) in conjunction with an advanced engineering computer programming language (Fortran 2003) based on an objected oriented programming (OOP) approach. This research provides four main contributions. First, a critical review of the current state of obtaining the computational capability for creep damage analysis. This critical review presents the advantages through the use of in-house software in analysing creep damage behaviour and the state-of-the-art research advancements and technologies need to be involved in developing in-house software. Second, the proposed OOP approach in design and development of in-house FE software for creep damage analysis. Third, the prototyping and implementation of a practical in-house FE software HITSI for analysing creep damage behaviour. The general flow diagram and development strategy of HITSI were proposed. Fourth, the benchmark test of HITSI via the numerical investigation of creep damage behaviour of a Cr-Mo-V steam pipe weldment case. The efficiency of the integration algorithms (Euler and Runge-Kutta) and normalized Kachanov-Rabotnov creep damage constitutive equation was investigated and commented. Generally, this project provides a novel in-house software prototype that allow the scientist to simulate the behaviour of creep damage in particular to analysis the evolution of creep damage in welds.

Noroviruses (NoV) and Hepatitis A viruses (HAV) are the most commonly implicated viruses in foodborne disease. Their transmission is mainly via the fecal-oral route and distribution of contaminated foods has lead to large outbreaks. Thus, it is crucial that contaminated foods be identified promptly. Detection by cell culture is not possible for these viruses so that researchers rely on the reverse transcription polymerase chain reaction (RT-PCR). Prior to detection, however, viruses must be isolated from foods and, as of yet, no one method has been found applicable to a large variety of food matrices. Problems with existing methods include, but are not limited to, the co-extraction of inhibitory molecules and lack of sensitivity. In addition, they are labour-intensive and time consuming. Therefore, the aims of this research project were to develop a novel methodology for the rapid and sensitive isolation and detection of NoV and HAV from select food matrices. In the first part of these studies, TRIzolRTM reagent and the RT-PCR were used to isolate and detect feline calicivirus (FCV) (a norovirus surrogate) from select artificially-inoculated foods. However, the co-extraction of PCR inhibitors resulted in false-negative results. RNA purification methods were then compared prior to detection and Oligo d (T) beads provided for the best sensitivity. However, virus capture was not sufficiently sensitive to be applied to outbreak situations. In the second part of this thesis, the Pathatrix(TM) system was applied to the isolation of HAV and NoV from a variety of foods with the use of positively-charged (cationic) magnetic beads. The use of the Pathatrix(TM) machinery has led to success in detecting a wide range of bacteria from various food matrices, and we were the first to report on its use for the concentration of viruses. When combined with the RT-PCR for detection, the Pathatrix(TM) system was able to detect HAV from inoculated foods at levels typically found in outbreak situations. Though results were not as sensitive with NoV-inoculated foods, the methodology was successful at detecting NoV in outbreak food samples. Furthermore, the cationic beads used in the Pathatrix(TM) system were able to simultaneously isolate two contaminating viruses from food samples. Therefore, the Pathatrix(TM) methodology reported herein is a very sensitive and rapid method that holds promise for the isolation and detection of HAV and NoV in outbreak situations.