Electrodynamic tether system study

The purpose of this program is to define an Electrodynamic Tether System (ETS) that could be erected from the space station and/or platforms to function as an energy storage device. A schematic representation of the ETS concept mounted on the space station is presented. In addition to the hardware design and configuration efforts, studies are also documented involving simulations of the Earth's magnetic fields and the effects this has on overall system efficiency calculations. Also discussed are some preliminary computer simulations of orbit perturbations caused by the cyclic/night operations of the ETS. System cost estimates, an outline for future development testing for the ETS system, and conclusions and recommendations are also provided

Gas bubbles investigation in contaminated water using optical tomography based on independent component analysis method

This paper presents the results of concentration profiles for gas bubble flow in a vertical pipeline containing contaminated water using an optical tomography system. The concentration profiles for the bubble flow quantities are investigated under five different flows conditions, a single bubble, double bubbles, 25% of air opening, 50% of air opening, and 100% of air opening flow rates where a valve is used to control the gas flow in the vertical pipeline. The system is aided by the independent component analysis (ICA) algorithm to reconstruct the concentration profiles of the liquid-gas flow. The behaviour of the gas bubbles was investigated in contaminated water in which the water sample was prepared by adding 25 mL of colour ingredients to 3 liters of pure water. The result shows that the application of ICA has enabled the system to detect the presence of gas bubbles in contaminated water. This information provides vital information on the flow inside the pipe and hence could be very significant in increasing the efficiency of the process industries

Development of a pragmatic framework to help food and drink manufacturers select the most sustainable food waste valorisation strategy

Food waste is a significant contemporary issue in the UK, with substantial environmental, social and economic costs to the nation. Whilst efforts to reduce food waste are laudable, a significant proportion of food and drink manufacturer waste is unavoidable. On the one hand, there is a drive from industry to reclaim as much value from this waste as possible, for example, by conversion to valuable products in what is known as “valorisation”. At the same time, growing social and legislative pressures mean that any attempts to valorise food waste must be performed in a sustainable manner. However, for every company and its specific food wastes, there will be multiple valorisation possibilities and few tools exist that allow food and drink manufacturers to identify which is most profitable and sustainable for them. Such a decision would need to not only consider environmental, social and economic performance, but also how ready the technology is and how well it aligns with that company's strategy. In response, this paper develops and presents a hybrid framework that guides a company in modelling the volumes/seasonality of its wastes, identifying potential valorisation options and selecting appropriate indicators for environmental, social and economic performance as well as technological maturity and alignment with company goals. The framework guides users in analyzing economic and environmental performance using Cost-Benefit Analysis and Life Cycle Assessment respectively. The results can then be ranked alongside those for social performance, technological maturity and alignment with company goals using a weighted sum model variant of Multi-Criteria Decision Analysis to facilitate easy visual comparison. This framework is demonstrated in the form of a case study with a major UK fruit consolidator to identify the optimal strategy for managing their citrus waste. Possibilities identified included sale of imperfect but still edible waste via wholesale at a significantly reduced profit and the investment in facilities to extract higher value pectin from the same waste stream using a microwave assisted pectin extraction process. Results suggest that continued sale of waste to wholesale markets is currently the most beneficial in terms of economic viability and environmental performance, but that in the medium to long term, the projected growth in the market for pectin suggests this could become the most viable strategy

C2FTrans: Coarse-to-Fine Transformers for Medical Image Segmentation

Convolutional neural networks (CNN), the most prevailing architecture for deep-learning based medical image analysis, are still functionally limited by their intrinsic inductive biases and inadequate receptive fields. Transformer, born to address this issue, has drawn explosive attention in natural language processing and computer vision due to its remarkable ability in capturing long-range dependency. However, most recent transformer-based methods for medical image segmentation directly apply vanilla transformers as an auxiliary module in CNN-based methods, resulting in severe detail loss due to the rigid patch partitioning scheme in transformers. To address this problem, we propose C2FTrans, a novel multi-scale architecture that formulates medical image segmentation as a coarse-to-fine procedure. C2FTrans mainly consists of a cross-scale global transformer (CGT) which addresses local contextual similarity in CNN and a boundary-aware local transformer (BLT) which overcomes boundary uncertainty brought by rigid patch partitioning in transformers. Specifically, CGT builds global dependency across three different small-scale feature maps to obtain rich global semantic features with an acceptable computational cost, while BLT captures mid-range dependency by adaptively generating windows around boundaries under the guidance of entropy to reduce computational complexity and minimize detail loss based on large-scale feature maps. Extensive experimental results on three public datasets demonstrate the superior performance of C2FTrans against state-of-the-art CNN-based and transformer-based methods with fewer parameters and lower FLOPs. We believe the design of C2FTrans would further inspire future work on developing efficient and lightweight transformers for medical image segmentation. The source code of this paper is publicly available at https://github.com/xianlin7/C2FTrans

Application of optical tomography for monitoring gas bubbles flow based on independent component analysis algorithm

This paper presents the monitoring process of gas bubbles flow in water using an optical tomography system. The system is aided by an Independent Component Analysis (ICA) algorithm for distinguishing the gas bubbles in pure water. The optical attenuation model is implemented for studying the light transmissions to different media which is water and air. Several quantities of air are inserted using an air pump which is installed at the bottom of a flow pipe in order to produce the gas bubbles flow upwards. The quantity of air is controlled by using a valve and five types of bubble flow are investigated; a single bubble flow, double bubble’s flow, 25% of air opening, 50% of air opening and 100% of air opening. The concentration profiles of the gas bubble flow are constructed. The concentration profile obtained from the experiments shows that the ICA algorithm can be used as a tool for imaging the two-phase flow phase distribution

Engineering and water governance interactions in smallholder irrigation schemes for improved water management.

Masters Degree, University of KwaZulu-Natal, Durban.Smallholder Irrigation Schemes (SISs) in South Africa have reported below expectation performance, despite massive investments. A diagnosis of the SISs poor performance indicates prevalence of infrastructural deficiencies, as well as poor institutional setup. The government’s Irrigation Management Transfer (IMT) initiative compounds the problem. IMT placed irrigators in self-governance, which inadvertently made irrigators carry the burden of scheme Operation and Maintenance (O&M) costs. This study sought to investigate and evaluate how technical design principles i.e., technical aspect of irrigation design, interact with irrigation water governance for SISs in KwaZulu-Natal Province. The study hypothesized that the existing current water control infrastructure does relate to the water governance frameworks in the selected study sites. The study was carried out in Tugela Ferry Irrigation Scheme (TFIS) and Mooi-River Irrigation Scheme (MRIS). An infrastructure condition assessment was carried out followed by a root cause analysis. Questionnaires were then administered to relevant stakeholders to rate the degree of identified causal factors. Key informants ranked how water governance and infrastructure aspects are related. The data was processed using a fuzzy theory approach. Finally, structured questionnaires were administered to irrigators to establish how water governance impacted on water adequacy for crop production. A binary logit regression model was employed to process the data. Assessments revealed the poor condition of the infrastructure, such as deep cracks in canals and missing latches on hydrants. The study revealed that TFIS had a strong institutional setups according to the Closeness Coefficients( = 0.18), and clearly defined goals and objectives for the scheme operation. However, other governance aspects such as procedures ( = 0.17, = 0.16) were not strong. MRIS ( = 0.20) had a good standing on rules and regulations as compared to TFIS ( = 0.14). Eight water governance related statistically significant variables that influenced water adequacy were identified. The eight variables were irrigation scheme ( = 0.000), location of plot within the scheme ( = 0.008), training in water management ( = 0.012), satisfaction with irrigation schedule ( = 0.000), irrigation training ( = 0.085), farmer knowledge of governments aims in SIS ( = 0.012), availability of water licenses ( = 0.002), and water fees ( = 0.022). A descriptive analysis showed that 24% and 86% of the farmers in MRIS and TFIS respectively, had adequate water. The study concluded that the SISs lacked an O&M plan and the farmers were not willing to opt for collective action and iii cooperate in Water Users Association (WUAs) and Irrigation Management Committees (IMCs). Some of the water governance aspects were discordant with infrastructure characteristics and requirements, consequently, impacting on the water adequacy for the irrigators. Overall, the study proved the hypothesis that the water control infrastructure does not relate with the water governance framework. This study recommends that the stakeholders involved in SISs, i.e., government, extension workers, NGOs, should aid the irrigators in policy articulation. In addition, the WUA and IMCs should provide incentives to motivate farmers to actively participate in scheme O&M

The Governance of Insurance Undertakings

This open access volume of the AIDA Europe Research Series on Insurance Law and Regulation brings together contributions from authors with different legal cultures. It aims to identify the legal issues that arise from the intersection of two disciplines: insurance law and corporate/company law. These legal issues are examined mainly from the perspective of European Union (EU) law. However, there are also contributions from other legal systems, enriching the perspective with which to approach these issues

The Governance of Insurance Undertakings

This open access volume of the AIDA Europe Research Series on Insurance Law and Regulation brings together contributions from authors with different legal cultures. It aims to identify the legal issues that arise from the intersection of two disciplines: insurance law and corporate/company law. These legal issues are examined mainly from the perspective of European Union (EU) law. However, there are also contributions from other legal systems, enriching the perspective with which to approach these issues

Comprehensive Taxonomies of Nature- and Bio-inspired Optimization: Inspiration versus Algorithmic Behavior, Critical Analysis and Recommendations

In recent years, a great variety of nature- and bio-inspired algorithms has been reported in the literature. This algorithmic family simulates different biological processes observed in Nature in order to efficiently address complex optimization problems. In the last years the number of bio-inspired optimization approaches in literature has grown considerably, reaching unprecedented levels that dark the future prospects of this field of research. This paper addresses this problem by proposing two comprehensive, principle-based taxonomies that allow researchers to organize existing and future algorithmic developments into well-defined categories, considering two different criteria: the source of inspiration and the behavior of each algorithm. Using these taxonomies we review more than three hundred publications dealing with nature-inspired and bio-inspired algorithms, and proposals falling within each of these categories are examined, leading to a critical summary of design trends and similarities between them, and the identification of the most similar classical algorithm for each reviewed paper. From our analysis we conclude that a poor relationship is often found between the natural inspiration of an algorithm and its behavior. Furthermore, similarities in terms of behavior between different algorithms are greater than what is claimed in their public disclosure: specifically, we show that more than one-third of the reviewed bio-inspired solvers are versions of classical algorithms. Grounded on the conclusions of our critical analysis, we give several recommendations and points of improvement for better methodological practices in this active and growing research field.Comment: 76 pages, 6 figure