Teff (Eragrostis tef) processing,utilization and future opportunities: a review

The demand for food production has been constantly increasing due to rising population. In developed countries, for example, the emergence of regional production of old grains that are rarely utilized, along with the production of commonly consumed grains, has gained importance in recent years. These grains, known collectively as ancient or heirloom grains, have offered both farmers and consumers novel ways of cultivation and products with interesting taste, characteristics and nutritional value. Among the 30 000 plant species known, only five cereals currently provide more than 50% of the world's energy intake – bread wheat (Triticum aestivum), rice (Oryza sativa), sorghum (Sorghum bicolor), millets (Panicum sp.) and maize (Zea mays). The excessive utilization of these selected species has a great potential to cause genetic losses and difficulty in bridging future agricultural demands. Teff (Eragrostis tef), an ancient grain extensively cultivated in countries like Eritrea and Ethiopia, provides promising alternatives for new food uses since its nutritional value is significantly higher than most others cereal grains. The absence of gluten allows flexibility in food utilization since it can be directly substituted to gluten-containing products. The grain also offers an excellent balance of essential amino acids and minerals, which can fulfil the recommended daily intake and eliminates the need for fortification and enrichment. This review provides a general overview of the physical properties and nutritional composition of teff grains related to processing and applications in the food and feed industries. The current status of teff utilization, as well as the challenges in production and commercialization, and future opportunities is presented and discussed.     

Encapsulation of PV modules using ethylene vinyl acetate copolymer as a pottant: A critical review

The primary purpose of this work is to review the literature about what is and is not known about using ethylene vinyl acetate (EVA0 copolymer as the encapsulant (or pottant) material in photovoltaic (PV) modules. Secondary purposes include elucidating the complexity of the encapsulation problem, providing an overview about encapsulation of PV cells and modules, providing a historical overview of the relevant research and development on EVA, summarizing performance losses reported for PV systems deployed since ca. 1981, and summarizing the general problems of polymer stability in a solar environment. We also provide a critical review of aspects of reported work for cases that we believe are important.Failure modes resolved in the early work to establish reliability of deployed modules and the purposes and properties of pottants, are summarized. Typical performance losses in large field-deployed, large-scale systems ranging from 1% to 10% per year are given quantitatively, and qualitative reports of EVA discoloration are summarized with respect to ultraviolet (UV), world-wide location and site dependence.The general stability of polymers and their desirable bulk properties for solar utilization are given. The stabilization formulation for EVA, its effectiveness, and changes in it during degradation are discussed. The degradation mechanisms for the base resin, e.g., unstabilized Elvax 150^TM, and stabilized EVA are indicated for literature dating to the early 1950s, and the role played by unsaturated chromophores is indicated. The limited number of studies relating discoloration and PV cell efficiency are summarized.Observed degradation of EVA or the unstabilized base resin in the laboratory and examples used to measure the degradation are summarized in sections entitled: (1) thermally-induced degradation; (2) photodegradation and photothermal degradation of EVA in different temperature regimes; (3) photobleaching and photodegradation of the UV absorber and cross-linking agent; (4) acetic acid and metal and metal-oxide catalyzed oxidative degradation; and (5) discolaration and PV cell efficiency losses.Processing effects/influences on EVA stability are discussed in sections entitled: (1) EVA raw materials and extruded, uncured films; (2) thermal encapsulation processes; (3) effects of lamination, curing, and curing peroxide on gel content and chromophores formed; and (4) incomplete shielding of curing-generated chromophores. A summary is given for the limited number of accelerated lifetime testing efforts and examples of erroneous service lifetime predictions for EVA are discussed. The known factors that effect the discoloration rate of several EVA formulations are discussed in which the reduction in rate by using UV-absorbing superstrates is a prime example. A summary is given of what is and is not known about EVA degradation mechanisms, degradation from exposures in field-deployed modeules and/or laboratory testing, and factors that contribute to EVA stability or degradation. Finally, conclusions about using Elvax 150 in EVA formulations are summarized, and future prospects for developing the next-generation pottant for encapsulating PV modules are discussed.     

Electronic protection and routing optimization of MANETs operating in an electronic warfare environment

Domination of the electromagnetic spectrum is a crucial component of the 21st century warfare. In the harsh electromagnetic environment of the modern battlefield, it is of the utmost importance to deny the opposing force the opportunity to attack or exploit the detection/interception of friendly communications assets through the deployment of electronic protection (EP) measures in order to attain low probability of detection (LPD), low probability of interception (LPI) and anti-jam (A/J). Given that directional antennas are a suitable means to achieve both extended range and LPD/LPI, this paper proposes mechanisms to optimize the trade-off between these capabilities, minimizing the number of hops and end-to-end delay when routing packets in a multi-hop ad-hoc network, while taking into account stealth requirements. The novel scheme is based on a variant of Fisheye State Routing, coupled with a power control algorithm to guarantee a LPD/LPI beyond the zone covered by the omni-directional radiation footprint of the network. The performance of the proposed scheme is evaluated through computer simulation.     

Catalysis, the turntable for a clean future

Upgrading the bottom of the barrel for clean fuel production, developing new engines with optimized catalytic posttreatments, implementing clean catalytic combustion technologies, improving the overall CO₂ balance via catalytic processes and, lastly, developing new water purification techniques represent major upheavals in catalysis linked to refining and environmental protection. This paper, thus, will focus on the determining contribution of catalysis to the most recent achievements in these domains. A technico-economic approach will follow, underlining their main incentives and drawbacks within the framework of future environmental constraints.     

A network-based mobility management scheme for future Internet

The current Internet was originally designed for “fixed” terminals and can hardly support mobility. It is necessary to develop new mobility management schemes for the future Internet. This paper proposes an Identifiers Separating and Mapping Scheme (ISMS), which is a candidate for the future Internet mobility management, and discusses the basic principles and detailed message flow. ISMS is a network-based mobility management scheme that takes advantage of the identity and location separation. The mobility entities in the core network are responsible for the location management. ISMS is designed to satisfy the requirements of faster handover, route optimism, advanced management, location privacy and security. The average handover delay of ISMS is on the order of milliseconds only, which is far smaller than that of Mobile IPv6. Analyses show that ISMS can reduce packet overhead on wireless channels. We build a prototype and perform some experiments. Results verify the feasibility of ISMS.     

融合内容和服务的未来网络体系架构

互联网难以适应其通信模式由主机为中心向以内容和服务为中心的转变,从而提出了融合内容和服务的未来网络体系架构(Content and Service Aware Network:CoreNet)。CoreNet基于面向内容和服务的设计理念,并通过灵活的协议栈"腰"设计允许应用显式地表达它们的通信意愿,使得网络能感知不同应用模式并进行优化处理。同时,通过网络内置缓存和高效任播路由,提升内容分发和服务获取的效率,适应未来人机物三元融合创新应用的需求。     

Research and prospect of ceramics for automotive disc-brakes

This article mainly discusses the research status and development trends of ceramics for automotive disc-brakes. According to the ceramic disc-brakes, various properties and characteristics, including fracture toughness, strength, compactness, corrosion resistance, wear resistance, micro-morphology, and thermal stabilities are analyzed. In the field of disc-brakes research, the research directions of the ceramics, including high-temperature performance, bionic structure, layered structure, porous structure, eutectic performance, superhard structure, and machinability are analyzed. The analysis of ceramics is expected to find disc-brake materials in line with the future development trends.     

Ergonomics in the past and the future: from a German perspective to an international one

Looking at the past there are more or less fragmented approaches in ergonomics as well as in management. Especially in Germany, the ‘Lean Management wave’ weakened ergonomics in industry. On the other hand, there is a growing demand for holistic concepts—and ergonomics can by definition be understood as holistic. Many of the newer approaches in management include ODAM or macroergonomics elements. In building up a stronger relationship between macro- and micro-ergonomics, the whole discipline could be promoted. This also requires the fulfilment of some preconditions like systematically gathering and presenting ‘best practices’, which show that ergonomics pays off.     

A 10 year installation program for wave energy in Ireland: A case study sensitivity analysis on financial returns

This paper is a case study which examines the finances of a proposed installation schedule of 500 MW of a wave energy device type in Ireland. The novel aspects of the analysis were the modelling of the combined influence of learning curves, supply and demand rates as well as future cost of cash on the phased deployment over the 10 years. There are many studies which have examined the economics of renewable energy project installations, including wave energy. However, there is lack of research in the impact and implications of phased installations over time, especially when using a feed-in tariff (FIT) revenue mechanism. The goal of the study was twofold. The first goal was to assess the viability of the current Irish feed-in tariff within the context of a phased installation program for the wave energy device chosen for the study, and measures required to produce a positive rate of return. The second aim was to assess the impact of learning curve, supply/demand curves and future cost of cash on phased project installations. The wave energy device chosen for the study was the Pelamis P1 and the economic model used was NAVITAS, created by HMRC. The assessment was based on net present value and internal rate of return. The wave energy data for the study was 2007 from M4 of the west coast of Ireland, obtained from Marine Institute, Ireland. Results from the case study indicated that the high initial costs for the case study wave energy device had a significant impact on financial returns. Results of the case study indicate that higher tariffs may be required than the current Irish, static, nonindex linked, FIT to foster positive returns for future wave energy projects, especially if phased installations are considered, which are susceptible to future cash and supply/demand factors. The large range of sensitivity factors assessed in the case study demonstrates the vulnerable nature of these large scale projects when estimating financial returns. Further studies will be required to assess multiple device types, update initial costs for wave energy devices, provide reliable power matrices, as well as appropriate learning curve and supply demand rates.     

Exploring to direct the reaction pathway for hydrogenation of levulinic acid into γ-valerolactone for future Clean-Energy Vehicles over a magnetic Cu-Ni catalyst

A cheap and magnetic Ni/Cu/Al/Fe catalyst for the selective hydrogenation of LA into GVL catalysts was prepared by sol-gel method. The reaction pathway was systematically studied by examining the reaction conditions, such as reaction pressure, catalyst loadings, water content, and reaction temperature. Higher reaction pressure and catalyst loadings were prior to form HA, then MHV, finally GVL; ML was easily to form with a higher reaction temperature. Water, as a key role, which was in favor to form HA, then MHV, finally GVL; more important, a higher LA conversion could be obtained in methanol as the solvent with some certain content of water. And, it can give a reference for future new clean energy vehicles' application.