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41.
Bulk density, specific heat capacity, bulk thermal conductivity and bulk thermal diffusivity of medium-grain rough rice (LIDO cultivar) have been studied. Specific heat was determined by DSC, thermal conductivity by the probe method and bulk thermal conductivity indirectly from bulk density, specific heat capacity and bulk thermal conductivity. All the thermal properties have been determined at different moisture contents and temperatures used during cooling and storage operations and the effect of these variables has been investigated. It has been shown that moisture content has the greatest effect on specific heat and bulk thermal conductivity. Temperature also affected these thermal properties, but to a smaller extent. Mathematical expressions have been developed to determine each of these thermophysical properties as a function of moisture content and temperature.List of Abbreviations and Symbols Cp Specific heat capacity (kJ/kg °C) - k Bulk thermal conductivity (W/m °C) - T Temperature (ºC) - W Moisture content (%, d.b.) - Bulk thermal diffusivity (m2/s) - Bulk density (kg/m3)  相似文献   
42.
Discharge of Green House Gases (GHGs) and the management of municipal solid waste (MSW) continue to be a major challenge particularly in growing economies. However, these are resources which can be converted to green energy. Landfill gas which is essentially methane (50–55%) and carbon dioxide (40–45%) (both GHGs) is released from MSW by biodegradation processes. The estimation of this methane and its economic and environmental benefits for environmental sustainability are the objectives of this study. Methane emission from MSW disposed of in landfills was estimated using Intergovernmental Panel on Climate Change (IPCC) methodology. From the study, based on 8,196,000 tonnes MSW generated in Peninsular Malaysia in 2010, anthropogenic methane emission of about 310,220 tonnes per year was estimated. This was estimated to generate 1.9 billion kWh of electricity year?1 worth over RM 570 million (US$190 million). In addition, this leads to carbon dioxide reduction of 6,514,620 tonnes year?1 equivalent to carbon credit of over RM 257 million (US$85 million). These results were also projected for 2015 and 2020 and the outcomes are promising. Therefore, the exploration of this resource, besides the economic benefits helps in reducing the dependence on the depleting fossil fuel and hence broadening the fuel base of the country.  相似文献   
43.
There has been a growing interest in plant proteins due to their beneficial health effects, low cost and variety of applications in food industries. The low solubility of lentil proteins (LPs) is one of the significant factors that limit their use in food applications. Quinoa proteins (QPs), which have high water solubility, were combined with LPs at pH 12 to generate LP-QP complexes to generate pH-based soluble protein compounds. The LP-QP complexes demonstrated a large surface charge with an increase solubilisation of the protein complexes by more than 85%, together with resistance to protein aggregation. The combination of LPs to QPs led to a significant increase (P < 0.05) in unique tertiary and secondary protein structures as determined by the protein–protein interaction (PPI) technique involving pH recycling. Interactions between LPs and QPs affected the surface morphology of the protein complexes formed. Electrostatic interactions, hydrophobic forces and hydrogen bonding were indicated to play key roles in the PPIs. The capacity of pH cycling to illustrate the above protein interactions shows that this is a robust approach for assessing the emulsion and foaming properties of food proteins.  相似文献   
44.
To improve the resource limitation of mobile devices, mobile users may utilize cloud-computational and storage services. Although the utilization of the cloud services improves the processing and storage capacity of mobile devices, the migration of confidential information on untrusted cloud raises security and privacy issues. Considering the security of mobile-cloud-computing subscribers’ information, a mechanism to authenticate legitimate mobile users in the cloud environment is sought. Usually, the mobile users are authenticated in the cloud environment through digital credential methods, such as password. Once the users’ credential information theft occurs, the adversary can use the hacked information for impersonating the mobile user later on. The alarming situation is that the mobile user is unaware about adversary’s malicious activities. In this paper, a light-weight security scheme is proposed for mobile user in cloud environment to protect the mobile user’s identity with dynamic credentials. The proposed scheme offloads the frequently occurring dynamic credential generation operations on a trusted entity to keep minimum processing burden on the mobile device. To enhance the security and reliability of the scheme, the credential information is updated frequently on the basis of mobile-cloud packets exchange. Furthermore, the proposed scheme is compared with the existing scheme on the basis of performance metrics i.e. turnaround time and energy consumption. The experimental results for the proposed scheme showed significant improvement in turnaround time and energy consumption as compared to the existing scheme.  相似文献   
45.
New coding schemes are increasingly being developed to adapt multisensor and communication systems to the requirements of the current technological environment. In some cases, the practical implementation of these schemes involves a great amount of signal processing operations. In order to achieve and make suitable their use in different platforms, efficient algorithms are required to process coding. In the last years, a new kind of complementary sequences, known as Generalized Pairwise Complementary sequences, has been proposed. These sequences provide high noise immunity when they are applied to multiuser systems, as well as a low cross‐correlation, which is convenient in those applications. The aim of this paper is to propose optimized generation and correlation architectures for Generalized Pairwise Complementary sequences that would allow to process a complete set using a reduced amount of operations. An analytical demonstration is provided, with a final comparison to evaluate the reduction with regard to other algorithms. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
46.
Dysregulation of retinal function in the early stages of light-induced retinal degeneration involves pannexins and connexins. These two types of proteins may contribute to channels that release ATP, leading to activation of the inflammasome pathway, spread of inflammation and retinal dysfunction. However, the effect of pannexin channel block alone or block of both pannexin channels and connexin hemichannels in parallel on retinal activity in vivo is unknown. In this study, the pannexin channel blocker probenecid and the connexin hemichannel blocker tonabersat were used in the light-damaged rat retina. Retinal function was evaluated using electroretinography (ERG), retinal structure was analyzed using optical coherence tomography (OCT) imaging and the tissue response to light-induced injury was assessed immunohistochemically with antibodies against glial fibrillary acidic protein (GFAP), Ionized calcium binding adaptor molecule 1 (Iba-1) and Connexin43 (Cx43). Probenecid did not further enhance the therapeutic effect of connexin hemichannel block in this model, but on its own improved activity of certain inner retina neurons. The therapeutic benefit of blocking connexin hemichannels was further evaluated by comparing these data against results from our previously published studies that also used the light-damaged rat retina model. The analysis showed that treatment with tonabersat alone was better than probenecid alone at restoring retinal function in the light-damaged retina model. The results assist in the interpretation of the differential action of connexin hemichannel and pannexin channel therapeutics for potential treatment of retinal diseases.  相似文献   
47.
 Short-time blanched (2 min, 90  °C), long-time blanched (30 min, 90  °C) and non-blanched potato slices were dried in a convective air drier and their mechanical and rehydration properties were compared. Blanching increased the flexibility and strength of dried potato slices, although the effects of short and long blanching were not significantly different. Unblanched potato slices did not have larger rehydration ratios than blanched ones. After rehydration for 30 min, samples from all treatments had higher strength and flexibility than cooked potatoes. Received: 2 November 1998 / Revised version: 15 February 1999  相似文献   
48.
This research was focused on the production of polyunsaturated fatty acid concentrates from a farmed rainbow trout (Oncorhynchus mykiss) by‐product (i.e. belly muscle). The effect of different process variables (urea/fatty acids (FA) contents ratio, crystallisation time and temperature and stirring speed of the urea/FA mixture) on the lipid oxidation development during the urea complexation process was investigated. For this purpose, an experimental design (26 runs) following the response‐surface methodology was developed. As a result, peroxide value and TOTOX index showed to be dependent on the crystallisation time and temperature and the urea/FA ratio, while no influence of the crystallisation stirring speed was detected on both indices; additionally, polyene index was affected by the urea/FA ratio and its interaction with the crystallisation time. An optimised desirability score near 1.0 was attained provided values of 2.8 °C, 3.05 h and 3.57 were applied for crystallisation temperature, crystallisation time and urea/FA ratio, respectively.  相似文献   
49.
This paper presents the numerical simulation of an industrial multi-step deep drawing process. A large strain finite element formulation including a hyperelastic elastoplastic constitutive model and a contact-friction law is used to this end where the steel sheet material parameters considered in the analysis are previously derived through a characterization procedure of its mechanical response. The numerical predictions of the final shape and thickness distribution of the blank are compared and discussed with available experimental values measured at the end of three successive drawing steps. In addition, a plastic work-based damage index is used to assess failure occurrence during the process. The damage values computed at the end of the drawing process are found to be lower than that corresponding to rupture in the tensile test, considered here as the threshold of failure, confirming, as observed experimentally, that neither fracture nor necking is developed in the blank during the whole drawing process. Finally, the possibility to carry out a reduced two-step drawing process, obtained by merging the second and third steps of the three-step process, is precluded since the damage criterion predicts in this case excessively large values that indicate that failure may occur in specific zones of the sheet.  相似文献   
50.
Nowadays, service economy efficiencies are key to keep competitiveness and increase market advantages. The development of Product-Service Systems (PSS) can be an interesting strategy as they seek to improve the business performance of all the participants in the value chain. This paper proposes a novel reliability-based reward scheme for use-oriented PSS contracts. In a PSS instead of paying for the product, the client pays a fee for its performance. The contribution of this work to the existing literature is to provide a quantitative tool for the development of a use-oriented PSS contract based on non-repairable component reliability and risk sharing. It can be extended to other performance metrics such as availability and reliability. A well designed PSS achieves a mutual growth agreement for the client and the supplier if it aligns their interests through channel coordination. This is achieved by balancing the improvement in the expected cost and profit for the client and the supplier, respectively. The improvement is measured with respect to a baseline scenario where no PSS contract exists. The methodology is tested using a case study that analyses mining haul truck tires. The results show a significant overall improvement in the main key performance indicators and environmental impact of the value chain.  相似文献   
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