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51.
The effects of storage temperature, oxygen permeability of packaging material and variety on oxidative stability of vacuum-packaged walnut kernels were studied over a 12 months storage period. The oxidation experiments applied to two popular walnut varieties (Yalova-1 and Yalova-3) grown in Turkey. The peroxide values and hexanal contents of walnut samples significantly increased (p < 0.01) during storage at 30 °C. The highest hexanal content (4464.5–6406.9 μg/kg) were observed in Yalova-3 variety stored at 30 °C for 12 months in Polyamide/Polyethylene film pouches (oxygen permeability: 63.4 ± 0.4 mL/m2/24 h (23 °C)) with 90 μm total thickness. The effect of storage temperature and variety on lipid oxidation was found to be higher than the effect of oxygen permeability of the packaging material. It was concluded that for vacuum-packed walnut kernels in PA/PE film pouches having 63.4 ± 0.4 mL/m2/24 h (23 °C) oxygen permeability, 20 °C is sufficient to protect against oxidation for 12 months.  相似文献   
52.
Journal of Superconductivity and Novel Magnetism - The synthesis of nanoparticles by the continuous flow process is of great interest since it allows extensive control over reaction conditions with...  相似文献   
53.
Reinforcement learning is a learning scheme for finding the optimal policy to control a system, based on a scalar signal representing a reward or a punishment. If the observation of the system by the controller is sufficiently rich to represent the internal state of the system, the controller can achieve the optimal policy simply by learning reactive behavior. However, if the state of the controlled system cannot be assessed completely using current sensory observations, the controller must learn a dynamic behavior to achieve the optimal policy. In this paper, we propose a dynamic controller scheme which utilizes memory to uncover hidden states by using information about past system outputs, and makes control decisions using memory. This scheme integrates Q-learning, as proposed by Watkins, and recurrent neural networks of several types. It performs favorably in simulations which involve a task with hidden states. This work was presented, in part, at the International Symposium on Artificial Life and Robotics, Oita, Japan, February 18–20, 1996  相似文献   
54.
Most multimedia servers reported in the literature are designed to serve multiple and independent video/audio streams. We think that, in future, multimedia servers will also serve complete presentations. Multimedia presentations provide unique opportunities to develop algorithms for buffer management and admission control, as execution-time consumption requirements of presentations are known a priori. In this paper, we examine presentations in three different domains (heavyweight, middleweight, and lightweight) and provide buffer management and admission control algorithms for the three domains. We propose two improvements (flattening and dynamic-adjustments) on the schedules created for the heavyweight presentations. Results from a simulation environment are presented. Received June 9, 1998 / Accepted October 13, 1998  相似文献   
55.
Software and Systems Modeling - To sustain competitiveness in contemporary, fast-paced markets, organizations increasingly focus on innovating their business models to enhance current value...  相似文献   
56.
57.
Milk is important because of its composition, its consumption prevalence, and its use as a raw material for many food products. The milk’s shelf life, reliability during processing, and quality conservation should be considered by the consumer. However, in Turkey, raw milk is sold unpackaged and untreated (by physical processes or heat treatment) by street suppliers without the use of any of the required food conservation techniques. This type of milk is generally called ‘street milk’ (SM). This study was conducted to analyse the Turkish urban consumers’ (UCs) attitudes, behaviours, and perceptions with respect to SM. To achieve a 2.83 % sampling tolerance, 1222 consumers were interviewed in person, and the data were collected. Although 23.6 % of UCs prefer SM, the potential customer rate is 43.1–48.9 %. These UCs tend to choose SM because the product is perceived to be ‘organic’, ‘pure’, and ‘natural’ and because they are suspicious of packaged/processed milk. In this study, the socio-economic statuses (SES) and age differences were identified (P < 0.05), and it was found that the 45+ age group and the low SES group have more positive views about SM. Thus, these groups must be made aware of the differences between ‘raw milk’ and ‘SM’, as well as the safety risks of SM and the importance of the processing and storing of dairy products, including milk.  相似文献   
58.
This paper presents a new model updating method based on minimization of an index called Miscorrelation Index (MCI), which is introduced to localize the coordinates carrying error in a finite element (FE) model. MCI can be calculated from measured frequency response functions (FRFs) and dynamic stiffness matrix of the FE model for each coordinate as a function of frequency. Nonzero numerical values for MCI of a coordinate indicate errors in one or more elements of the system matrices corresponding to this coordinate. The sensitivity-driven model updating method presented in this study (MCI Sensitivity Method) is based on minimization of MCI. The application of the method is illustrated with four case studies. In the first and second examples a discrete system is considered, and computationally generated and polluted FRFs are used as pseudo-test data. In the third and fourth case studies, real test data is used and the performance of the method in practical applications is demonstrated on the benchmark structure built to simulate the dynamic behavior of an airplane, namely, GARTEUR SM-AG19 test bed. It is concluded that MCI Sensitivity Method yields successful results even when the measured responses of only a few coordinates are used, especially when miscorrelation is due to local errors.  相似文献   
59.
Widely consumed legumes including chickpeas, red kidney beans, haricot beans, yellow lentils, red lentils and green lentils were analysed to determine the content of non-isoflavone phytoestrogenic compounds such as quercetin, rutin, apigenin, coumestrol and lignan (matairesinol and secoisolariciresinol). Methanolic extracts obtained by ultrasound-assisted extraction were analysed by the triple quadrupole LC–MS/MS. Red kidney beans were the best source of quercetin (603.2 ± 307.2 μg/kg) and rutin (73.4 ± 14.0 μg/kg). Apigenin and secoisolariciresinol contents were the highest in yellow lentils (18.5 ± 0.84 μg/kg) and haricot beans (451.9 ± 192.2 μg/kg), respectively. Coumestrol contents of haricot beans (18.5 ± 1.45 μg/kg) and red kidney beans (18.5 ± 1.26 μg/kg) were equal to each other, and these were determined as the highest coumestrol content values. The best sources of matairesinol occurred in green lentils (28.2 ± 0.18 μg/kg) and chickpeas (27.7 ± 1.83 μg/kg). Differences between contents of each sample of the same legume were significant and remarkable, especially for quercetin and secoisolariciresinol.  相似文献   
60.
Changes in food consumption habits and the developments set forth in the area of health and nutrition also change consumer expectations and demands. Sugar-free foodstuffs and products that have prebiotic activity are among the primary features of such expectations and demands. In the present study, the effects of substituting fine sugar with isomalt and maltitol in milk chocolate samples that contain inulin (9.0 % w/w), which is a substance with prebiotic activity, and the use of varying conching temperatures (CT) (50, 55 and 60 °C) in the sample preparation process on their physical (colour, hardness, water activity) and rheological properties were examined. Rheological data were obtained using the Herschel–Bulkley model which showed the best fitting for predicting rheology. It was determined that all properties included within the scope of the study are affected by the use of different bulk sweeteners or varying CT (P < 0.01). While colour properties, such as brightness (L*), hue angle (h°), water activity (aw) and rate index properties varied in a narrow range, it was determined that the yield stress and viscosity properties, which are among the important quality parameters of chocolate and can have determining effects on sensory properties, manifest variations within a broad range, depending on the CT and the bulk sweeteners used. It was concluded that maltitol is a more suitable fine sugar substitute in milk chocolates containing inulin.  相似文献   
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