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1.
Single image super-resolution (SISR), which aims to reconstruct a high-resolution (HR) image from a low-resolution (LR) observation, has been an active research topic in the area of image processing in recent decades. Particularly, deep learning-based super-resolution (SR) approaches have drawn much attention and have greatly improved the reconstruction performance on synthetic data. However, recent studies show that simulation results on synthetic data usually overestimate the capacity to super-resolve real-world images. In this context, more and more researchers devote themselves to develop SR approaches for realistic images. This article aims to make a comprehensive review on real-world single image super-resolution (RSISR). More specifically, this review covers the critical publicly available datasets and assessment metrics for RSISR, and four major categories of RSISR methods, namely the degradation modeling-based RSISR, image pairs-based RSISR, domain translation-based RSISR, and self-learning-based RSISR. Comparisons are also made among representative RSISR methods on benchmark datasets, in terms of both reconstruction quality and computational efficiency. Besides, we discuss challenges and promising research topics on RSISR.  相似文献   
2.
Hydrogen is emerging as a zero-carbon energy source for the sustainable future. Hydrogen station plays the role of supplying hydrogen to fuel cell vehicles. However, the small number of hydrogen stations has become the biggest obstacle to the promotion of hydrogen energy. As an important infrastructure for the development of hydrogen energy industry, the hydrogen station will not be able to support the promotion and application of hydrogen fuel cell vehicles if it cannot form a large scale. In addition, the layout of the hydrogen station network should be reasonable to avoid waste of resources. The study of hydrogen station location models has significant economic, social and military implications. Considering these circumstances, this review investigates the existing research efforts and conducted a comprehensive overview of these works on hydrogen station location models. In this review, we divide the hydrogen station location models into several categories according to the spatial dimension of the facility, the structure of the planning area, and the number of objectives. We present detailed explanations, formulations and different constraints for these models. Finally, we conclude the strengths and weaknesses of these models and provide available solutions. To our best knowledge, this review might help researchers get a comprehensive understanding of related researches in the hydrogen station location.  相似文献   
3.
无线传感器网络静态节点定位算法综述   总被引:1,自引:0,他引:1  
针对无线传感器网络静态节点定位算法特点,总结了无线传感器网络节点定位的基本原理、定位算法的最新进展及其评价标准。从基于测距的静态节点定位算法和无需测距的静态节点定位算法两个方面分类讨论了典型的静态节点定位算法,并对各算法的性能进行归纳比较,说明了目前算法存在的问题,并提出未来发展趋势。  相似文献   
4.
Thermal error caused by the thermal deformation is one of the most significant factors influencing the accuracy of the machine tool. Among all the heat sources which lead to the thermal distortions, the spindle is the main one. This paper presents an overview of the research about the compensation of the spindle thermal error. Thermal error compensation is considered as a more convenient, effective and cost-efficient way to reduce the thermal error compared with other thermal error control and reduction methods. Based on the analytical calculation, numerical analysis and experimental tests of the spindle thermal error, the thermal error models are established and then applied for implementing the thermal error compensation. Different kinds of methods adopted in testing, modeling and compensating are listed and discussed. In addition, because the thermal key points are vital to the temperature testing, thermal error modeling, and even influence the effectiveness of compensation, various approaches of selecting thermal key points are introduced as well. This paper aims to give a basic introduction of the whole process of the spindle thermal error compensation and presents a summary of methods applied on different topics of it.  相似文献   
5.
To reduce loss of hydrogen in storage vessels with high energy-to-weight-ratio, new materials, especially polymers, have to be developed as barrier materials. Very established methods for characterization of barrier materials with permeation measurements are the time-lag and flow rate method along with the differential pressure method, which resembles the nature of hydrogen vessel systems very well. Long measurement durations are necessary to gain suitable measurement data for these evaluation methods, and often restrictive conditions have to be fullfilled. For these reasons, common models for hydrogen permeation through single-layer and multi-layer membranes, as well as models for hydrogen gas properties were collected and reviewed. Using current computer power together with these models can reduce measurement time for characterization of the barrier properties of materials, while additional information about the quality of the measurement results is obtained.  相似文献   
6.
Global population growth and accelerated urbanisation have resulted in massive amounts of fossil fuel use and waste production. Because of its high energy content, pure nature, and fuel quality, hydrogen fuel is a viable option to fossil fuels. Biohydrogen from agricultural waste, in particular, piques concern because it generates hydrogen while still disposing of waste. This review conducted a bibliometric analysis of biohydrogen production from organic waste to trace the research trends and hotspots based on the literature in the Web of Science (WOS) database from 1970 to 2020. The present review article also focuses on highlighting various processes for converting organic waste into hydrogen, raw materials for biohydrogen production, and catalysts that could distil the latest perceptions that could shed light on a route advancing for successful catalyst design. It also seems that some intentions have been paid on studying waste materials such as pure polysaccharides, disaccharides, and monosaccharides. Among all the catalysts used, non-noble and low-cost active metals over reduced graphene oxide (rGO) support can significantly affect the activity of fermentative hydrogen production from organic waste materials. However, researches focusing on developing anaerobic membrane bioreactors for these technologies are still needed.  相似文献   
7.
在体育竞赛评审中,借助计算机智能算法完成辅助系统开发,能够完成动作细致评审,得到更加准确的评审结果。基于此,本文提出了系统结构框架,并对系统数据处理方法和动作识别算法进行了探讨。在系统功能实现的过程中,可以依靠深度特征和骨骼关节数据实现特征数据提取,然后利用傅里叶算法完成特征融合和动作分类识别。从系统功能测试结果来看,能够用于准确识别各组难度动作,满足竞赛评审辅助需求。  相似文献   
8.
ContextFor more than four decades it has been intuitively accepted that user involvement (UI) during system development lifecycle leads to system success. However when the researchers have evaluated the user involvement and system success (UI-SS) relationship empirically, the results were not always positive.ObjectiveOur objective was to explore the UI-SS relationship by synthesizing the results of all the studies that have empirically investigated this complex phenomenon.MethodWe performed a Systematic Literature Review (SLR) following the steps provided in the guidelines of Evidence Based Software Engineering. From the resulting studies we extracted data to answer our 9 research questions related to the UI-SS relationship, identification of users, perspectives of UI, benefits, problems and challenges of UI, degree and level of UI, relevance of stages of software development lifecycle (SDLC) and the research method employed on the UI-SS relationship.ResultsOur systematic review resulted in selecting 87 empirical studies published during the period 1980–2012. Among 87 studies reviewed, 52 reported that UI positively contributes to system success, 12 suggested a negative contribution and 23 were uncertain. The UI-SS relationship is neither direct nor binary, and there are various confounding factors that play their role. The identification of users, their degree/level of involvement, stage of SDLC for UI, and choice of research method have been claimed to have impact on the UI-SS relationship. However, there is not sufficient empirical evidence available to support these claims.ConclusionOur results have revealed that UI does contribute positively to system success. But it is a double edged sword and if not managed carefully it may cause more problems than benefits. Based on the analysis of 87 studies, we were able to identify factors for effective management of UI alluding to the causes for inconsistency in the results of published literature.  相似文献   
9.
Although potassium-ion batteries (KIBs) are considered a very promising energy storage system, their development for actual application still has a long way to go. Advanced electrode materials, as a fundamental component of KIBs, are essential for optimizing electrochemical performance and promoting effective energy storage. Due to their unique structural benefits in terms of cycle capability, strong ionic conductivity, and tunable operating voltage, polyanionic compounds are one type of viable electrode material for manufacturing high-performance KIBs. The huge size of K+ ion, on the other hand, places great demands on polyanionic materials, which must be able to withstand severe structural deformation during K+ intercalation/delamination. To maintain steady electrochemical performance, it is critical to follow the appropriate design guidelines for electrode materials. This paper provides a summary of current advancements in polyanionic compound for KIBs, with a focus on electrode material structural design. The effects of various parameters on electrochemical performance are examined and summarized. In addition, various viable solutions are proposed to address the impending issues posed by polyanionic compounds for KIBs, with the hope of providing a clearer picture of the field's future development path.  相似文献   
10.
In the era of digitalization, there are many emerging technologies, such as the Internet of Things (IoT), Digital Twin (DT), Cloud Computing and Artificial Intelligence (AI), which are quickly developped and used in product design and development. Among those technologies, DT is one promising technology which has been widely used in different industries, especially manufacturing, to monitor the performance, optimize the progresses, simulate the results and predict the potential errors. DT also plays various roles within the whole product lifecycle from design, manufacturing, delivery, use and end-of-life. With the growing demands of individualized products and implementation of Industry 4.0, DT can provide an effective solution for future product design, development and innovation. This paper aims to figure out the current states of DT research focusing on product design and development through summarizing typical industrial cases. Challenges and potential applications of DT in product design and development are also discussed to inspire future studies.  相似文献   
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