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91.
The aim of this article is the assessment of low-carbon energy technologies in Europe against a set of sustainability and resilience criteria. The assessment was based on a survey that was conducted among 40 European experts. Solar Photovoltaic was the technology that proved to achieve high performance against many criteria, whereas nuclear was assessed by the experts with relatively low performance against most of the criteria. Furthermore, it became evident that there is high degree of convergence between the experts, and therefore high degree of confidence, on specific aspects such as the high level of public resistance against Nuclear and the low stability of energy generation of wind onshore. The experts had major disagreements on the performance of carbon capture and storage (CCS) technologies against technological maturity and innovative ability criteria, which reveals a high degree of uncertainty on how CCS will be deployed in the future, pointing out a direction for future research.  相似文献   
92.
Politically-driven climate protection targets call for decarbonization and a massive reduction of total energy consumption by 2050. A comprehensive transformation of existing transport systems and individual mobility is needed to achieve this. There will be no energy transition (“Energiewende”) without a transport transition. Electromobility provides great savings compared to fossil-fueled transport. In addition information and communication technologies (ICT) have become a key factor of innovation and inter- and multimodality. With all structural changes (e.g. industrial restructuring or social change), converting existing organizational forms and mobility evokes conflicts. For example, competing spatial requirements of the energy sector and mobility as well as the exclusion of certain categories of persons are to be expected. Indeed, the transformation process is slowed down by shortcomings in the combination of energy and transport technologies, organizational culture and regulations. A number of questions still remain unanswered.  相似文献   
93.
Irrigation for smallholder farming systems is an important approach for sustainable intensification and increased productivity in Sub-Saharan Africa, provided investments in irrigation are properly targeted and accompanied by complementary improvements. Many GIS-based tools have been developed to identify suitable areas for investments in different types of small scale irrigation (SSI), but they do not explicitly address uncertainty on the data input and on the determination of factors that affect success of an investment in a given context. This paper addresses this problem by presenting an application of a decision-support targeting tool based on Bayesian networks (BNs) that can be used by non-expert policy-makers and investors to assess the potential success of specific technologies used for groundwater-based SSI. A case study application for the White Volta Basin in West Africa is presented to illustrate the BN approach.  相似文献   
94.
The increased level of emissions of carbon dioxide into the atmosphere due to burning of fossil fuels represents one of the main barriers toward the reduction of greenhouse gases and the control of global warming. In the last decades, the use of renewable and clean sources of energies such as solar and wind energies has been increased extensively. However, due to the tremendously increasing world energy demand, fossil fuels would continue in use for decades which necessitates the integration of carbon capture technologies (CCTs) in power plants. These technologies include oxycombustion, pre‐combustion, and post‐combustion carbon capture. Oxycombustion technology is one of the most promising carbon capture technologies as it can be applied with slight modifications to existing power plants or to new power plants. In this technology, fuel is burned using an oxidizer mixture of pure oxygen plus recycled exhaust gases (consists mainly of CO2). The oxycombustion process results in highly CO2‐concentrated exhaust gases, which facilitates the capture process of CO2 after H2O condensation. The captured CO2 can be used for industrial applications or can be sequestrated. The current work reviews the current status of oxycombustion technology and its applications in existing conventional combustion systems (including gas turbines and boilers) and novel oxygen transport reactors (OTRs). The review starts with an introduction to the available CCTs with emphasis on their different applications and limitations of use, followed by a review on oxycombustion applications in different combustion systems utilizing gaseous, liquid, and coal fuels. The current status and technology readiness level of oxycombustion technology is discussed. The novel application of oxycombustion technology in OTRs is analyzed in some details. The analyses of OTRs include oxygen permeation technique, fabrication of oxygen transport membranes (OTMs), calculation of oxygen permeation flux, and coupling between oxygen separation and oxycombustion of fuel within the same unit called OTR. The oxycombustion process inside OTR is analyzed considering coal and gaseous fuels. The future trends of oxycombustion technology are itemized and discussed in details in the present study including: (i) ITMs for syngas production; (ii) combustion utilizing liquid fuels in OTRs; (iii) oxy‐combustion integrated power plants and (iv) third generation technologies for CO2 capture. Techno‐economic analysis of oxycombustion integrated systems is also discussed trying to assess the future prospects of this technology. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
95.
This paper analyses the relationship between productive efficiency and online-social-networks (OSN) in Spanish telecommunications firms. A data-envelopment-analysis (DEA) is used and several indicators of business “social Media” activities are incorporated. A super-efficiency analysis and bootstrapping techniques are performed to increase the model's robustness and accuracy. Then, a logistic regression model is applied to characterise factors and drivers of good performance in OSN. Results reveal the company's ability to absorb and utilise OSNs as a key factor in improving the productive efficiency. This paper presents a model for assessing the strategic performance of the presence and activity in OSN.  相似文献   
96.
97.
This paper presents a thorough review of control technologies that have been applied to wastewater treatment processes in the environmental engineering regime in the past four decades. It aims to provide a comprehensive technological review for both water engineering professionals and control specialists, giving rise to a suite of up-to-date pathways to impact this field in light of the classified technology hubs. The assessment was conducted with respect to linear control, linearizing control, nonlinear control, and artificial intelligence-based control. The application domain of each technology hub was summarized into a set of comparative tables for a holistic assessment. Challenges and perspectives were offered to these field engineers to help orient their future endeavor.   相似文献   
98.
The effect of non-thermal technologies (ozone in aqueous solution, ultrasound and ultraviolet C radiation) and washings with chemical solutions (sodium hypochlorite and hydrogen peroxide) on safety and quality features of strawberries was studied. These treatments were applied before fruit storage at two different temperatures (4 and 15 °C). The overall impact on microbial loads (total mesophiles, and yeasts and moulds) and selected quality attributes (colour, firmness, pH, total anthocyanins and ascorbic acid content) was assessed.During storage under refrigerated temperature, washing with hydrogen peroxide solutions resulted in strawberries with lower microbial loads, when compared to the other treatments. However, it produced significant key quality attributes losses, such as colour and total anthocyanins content.The results presented show that ozone and ultrasound are promising alternatives to thermal treatments. The application of such technologies, before refrigerated storage of strawberries, allowed a satisfactory retention of all quality characteristics analysed, while being efficient in controlling microbial contamination.  相似文献   
99.
Advances in technology have a substantial impact on every aspect of our lives, ranging from the way we communicate to the way we travel. The Smart mobility at the European land borders (SMILE) project is geared towards the deployment of biometric technologies to optimize and monitor the flow of people at land borders. However, despite the anticipated benefits of deploying biometric technologies in border control, there are still divergent views on the use of such technologies by two primary stakeholders–travelers and border authorities. In this paper, we provide a comparison of travelers' and border authorities' views on the deployment of biometric technologies in border management. The overall goal of this study is to enable us to understand the concerns of travelers and border guards in order to facilitate the acceptance of biometric technologies for a secure and more convenient border crossing. Our method of inquiry consisted of in-person interviews with border guards (SMILE project's end users), observation and field visits (to the Hungarian-Romanian and Bulgarian-Romanian borders) and questionnaires for both travelers and border guards. As a result of our investigation, two conflicting trends emerged. On one hand, border guards argued that biometric technologies had the potential to be a very effective tool that would enhance security levels and make traveler identification and authentication procedures easy, fast and convenient. On the other hand, travelers were more concerned about the technologies representing a threat to fundamental rights, personal privacy and data protection.  相似文献   
100.
石油酸是原油和馏分油中普遍存在的腐蚀性物质,其主要成分为环烷酸并且含量可以高达90%以上。环烷酸具有羧酸的所有化学性质,所以常常造成严重的腐蚀,从而影响原油加工设备及油品使用设备的正常运行和使用寿命。随着近年来世界范围内高酸原油产量的逐渐增加,高原油及各种高酸值馏分油所带来的腐蚀与产品质量问题显得愈发严重,因此迫切需要开发出经济高效的脱酸技术与工艺路线。本文较为全面而详细地总结并评述了国内外原油及油品的各种脱酸技术方法。分析表明:目前所报道的各类脱酸工艺较多,其中工业应用的加氢脱酸效果虽好但是成本较高,而其他大多数脱酸方法都存在较多的缺点或不足,因此探寻一种绿色环保、经济高效并且具有较好普适性的油品脱酸工艺显得非常迫切而必要。酯化法脱酸具有加工工艺简单、不需要复杂的后继处理,几乎可以降低所有的高酸值原油和油品(轻质、重质馏分油以及渣油)的酸值,为原料油的进一步加工提供了方便。酯化脱酸工艺的关键在于高效催化剂的选择,而目前的催化酯化体系虽然脱酸率较高,但仍存在着反应时间较长的不足,相信通过反应过程强化等手段解决该问题以后,催化酯化脱酸工艺会被很快投入到原油及油品的脱酸实际工业生产中去。  相似文献   
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