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61.
Traditional cryptanalysis assumes that an adversary only has access to input and output pairs, but has no knowledge about internal states of the device. However, the advent of side-channel analysis showed that a cryptographic device can leak critical information. In this circumstance, Machine learning is known as a powerful and promising method of analysing of side-channel information. In this paper, an experimental investigation on a FPGA implementation of elliptic curve cryptography (ECC) was conducted to explore the efficiency of side-channel information characterisation based on machine learning techniques. In this work, machine learning is used in terms of principal component analysis (PCA) for the preprocessing stage and a Cascade-Forward Back-Propagation Neural Network (CFBP) as a multi-class classifier. The experimental results show that CFBP can be a promising approach in characterisation of side-channel information.  相似文献   
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This paper reports on a ‘bottom-up’ system of wheat seed technology transfer that was piloted in north–west Bangladesh with 45 mainly marginal (food insecure) farming families during the 2004–2005 wheat season, then scaled out to a further 545 mainly marginal, farming families during the 2006–2007 season. The system was devised following a survey which indicated that such farmers can obtain a 52% increase in wheat grain yield and extra income by switching from the old Kanchan variety to the newer, heat and disease-tolerant Shatabdi variety. The bottom-up wheat seed dissemination system involved the creation of an enabling environment which allowed poor and ultra-poor farmers to store and sell selected seed of recently-released wheat varieties that they produced in 20 decimal (0.08 ha) plots. During the pilot phase of the project in 2005, farmers produced 7, 976 kg of grain and more than 50% of this was selected as high quality seed, stored during the monsoon season and marketed to other farmers just prior to the following wheat season. This seed was sold at Tk25–30/kg and realised profits averaging Tk3,002 (€38.49; exchange rate was 78:1 in October 2005) per household. In 2007, the seed price had risen to Tk33–50/kg and a larger group of farmers produced, stored and marketed 168,800 kg of high quality wheat seed, which realised profits averaging Tk5,080, equivalent to €51 (exchange rate was 99.6:1 in October 2007), per household. This bottom up seed production and dissemination system met the wheat seed requirements of more than 1,400 neighbouring farmers in areas with a deficit of wheat seed for planting, and enabled poor and ultra-poor farmers to earn more than 50% of the income they needed to cross the local poverty line.
Stephen R. WaddingtonEmail:

Sam L. J. Page   Ph.D. I have been working in rural development for more than 30 years in both government and non-government sectors. My early research was concerned with pest management in food cropping systems and later I began investigating underlying causes of household food insecurity in southern Africa, as well as the use of indigenous food cropping systems to mitigate the impacts of HIV/AIDS. I am currently based at CABI Europe-UK, where I am implementing the Good Seed Initiative which aims to alleviate poverty by enabling food insecure farming families to profit from producing and marketing seed of indigenous and improved varieties. Dr. Baksh   is an experienced agricultural economist and Principal Scientific Officer in the Wheat Research Centre of the Bangladesh Agricultural Research Institute (BARI). He specialises in economic aspects of the rice–wheat cropping system that characterises much of south Asia and has published 20 scientific papers. For the past 8 years he has been the Principal Investigator for several DFID, IFAD, IRRI and CIMMYT funded projects that aim to design and disseminate resource-conserving technologies to improve the livelihoods of the poorest farming families in the region. Dr. Etienne Duveiller   is a plant pathologist specializing in cereal disease resistance and integrated crop management with more than 25 years experience in international agriculture and development projects. He received his M.Sc. (1980) and Ph.D. (1992) from University of Louvain (UCL) in Belgium and a special degree in social sciences from the Developing Countries Institute at the same university (1981). After working in capacity building in Bolivia for an NGO, and in Burundi on rice diseases, he joined CIMMYT Wheat Program in 1987. After10 years at CIMMYT headquarters in Mexico and frequent visits to South Asia, he spent 8 years on the Indian Subcontinent as CIMMYT regional pathologist based in Nepal and participated in several wheat disease surveys in central Asia and Iran. He returned to Mexico in 2006 as Head of Wheat Pathology at the CIMMYT Global Wheat program. Stephen Waddington   is an agronomist. He has 26 years of experience working with the International Maize and Wheat Improvement Centre (CIMMYT) and its partners in Mexico, southern and eastern Africa and in Bangladesh. His main research interests involve smallholder farming systems and participatory research, maize and wheat crop production agronomy, soil fertility and water management, and cereal yield physiology. He has considerable experience in capacity building and networking in many of these areas. Waddington was South Asia regional agronomist and head of the CIMMYT Office in Bangladesh from 2005 to 2007 and is currently located in Mexico.   相似文献   
63.
Bovine M. semimembranosus from different sexes of cattle were held at temperatures ranging from 0 to 35 °C until rigor and aged for up to 9 weeks. The waterholding capacity (WHC) of the beef increased with ageing as evidenced by the decline in drip loss measured gravimetrically, centrifugally and by pressure. Drip viscosity (P < 0.01), meat protein extractability (P < 0.05), spreadability (P < 0.01) and compressibility also increased with ageing. Evidence of structural changes was seen in SDS-PAGE confirming the physical changes. Meat spreadability under pressure and WHC were higher in samples with inherently higher pH relative to lower pH. The outcome of this study supports a hypothesis that the increase in WHC with ageing is due to the breakdown in meat structure and the creation of “sponge effect”, which disrupts the channels through which moisture is lost and physically entraps the free water in meat and reduce the amount that drips out.  相似文献   
64.
为改善涤纶网络丝仿麻织物的摩擦性能,分析了纤维、纱线、织物组织结构等因素对涤纶网络丝仿麻织物起毛起球性能、耐磨性能的影响,研究并制定了提高涤纶网络丝仿麻织物摩擦性能的树脂整理工艺。对树脂整理剂浓度、处理液温度、焙烘温度、焙烘时间、柔软剂浓度等工艺参数进行优化。结果表明:涤纶网络丝仿麻织物最佳整理工艺为树脂整理剂质量浓度50 g/L,处理液温度40 ℃,焙烘温度100 ℃,焙烘时间4 min,柔软剂质量浓度3 g/L;经最佳工艺整理后的织物在40 000次摩擦后的质量损失率由未整理时的12.13%下降到 5.34%,织物起毛起球等级由未整理时的1级提升到3~4级,并能基本保持织物原有的手感。  相似文献   
65.
Food Analytical Methods - A simple, rapid and sensitive GC-MS method using on-column injection was developed and validated to determine ergosterol (ERG) levels in maize and wheat. In this method,...  相似文献   
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Gelatin is one of the most important multifunctional biopolymers and is widely used as an essential ingredient in food, pharmaceutical, and cosmetics. Porcine gelatin is regarded as the leading source of gelatin globally then followed by bovine gelatin. Porcine sources are favored over other sources since they are less expensive. However, porcine gelatin is religiously prohibited to be consumed by Muslims and the Jewish community. It is predicted that the global demand for gelatin will increase significantly in the future. Therefore, a sustainable source of gelatin with efficient production and free of disease transmission must be developed. The highest quality of Bovidae-based gelatin (BG) was acquired through alkaline pretreatment, which displayed excellent physicochemical and rheological properties. The utilization of mammalian- and plant-based enzyme significantly increased the gelatin yield. The emulsifying and foaming properties of BG also showed good stability when incorporated into food and pharmaceutical products. Manipulation of extraction conditions has enabled the development of custom-made gelatin with desired properties. This review highlighted the various modifications of extraction and processing methods to improve the physicochemical and functional properties of Bovidae-based gelatin. An in-depth analysis of the crucial stage of collagen breakdown is also discussed, which involved acid, alkaline, and enzyme pretreatment, respectively. In addition, the unique characteristics and primary qualities of BG including protein content, amphoteric property, gel strength, emulsifying and viscosity properties, and foaming ability were presented. Finally, the applications and prospects of BG as the preferred gelatin source globally were outlined.  相似文献   
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