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排序方式: 共有6525条查询结果,搜索用时 250 毫秒
1.
《全球能源互联网(英文)》2022,5(6):618-626
A novel image sequence-based risk behavior detection method to achieve high-precision risk behavior detection for power maintenance personnel is proposed in this paper. In this method, the original image sequence data is first separated from the foreground and background. Then, the free anchor frame detection method is used in the foreground image to detect the personnel and correct their direction. Finally, human posture nodes are extracted from each frame of the image sequence, which are then used to identify the abnormal behavior of the human. Simulation experiment results demonstrate that the proposed algorithm has significant advantages in terms of the accuracy of human posture node detection and risk behavior identification. 相似文献
2.
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
3.
Esperanza González-Redondo 《建筑学研究前沿(英文版)》2022,11(2):255-277
The constructive analysis of Madrid's old timber-framed collective courtyard buildings, whether demolished, preserved intact, or enlarged, has achieved the dating of relevant case studies. New parameters established in this study set a chronology based on front sector original projects: old (1737–1788), pre-modern (1788–1847) and modern (1847–1892). The on-site inspection and archival research point to ongoing misleading construction in the historic Southern area. Some modern corralas erected on top of pre-existing buildings confirm the initial hypothesis. First dimensioning rules for new façades and the stability required in old ones before adding new storeys, maintaining the original masonry or double-layered system, are discovered. Undated buildings suggest their possible origin a la malicia and a later transformation into transitional corralas. Finally, an analysis of the demolished courtyards narrows down the dating and points to new conjectures in some preserved by showing their uneven layout, old features, and structural discordances in each sector. 相似文献
4.
Thomas RAINER 《景观设计学(英文)》2021,9(1):112
The ability of landscape architectural projects to mitigate the worst effects of climate change will depend upon designed ecological systems. These systems will be built with plants. Despite the recognition of ecology as an essential driver of landscapes, the professionals of landscape architecture too often lack the knowledge and practical skills to create robust vegetative systems. New approaches and tools are required. This article outlines principles and methods for designing biodiverse plant systems for urban sites. Planting methods that increase species richness, functional diversity, and spatial complexity are emphasized as a way of developing more resilient plantings. Selecting species with similar evolutionary adaptions to stress, disturbance, and competition—as well as creating multi-layered compositions of diverse plant morphologies—allows designers to create compatible, long-lived plant mixes. To balance the increased visual complexity of diverse plant mixes, the article explores design techniques to make plantings more appealing to the public. The strategies explored here are based on the projects, experience, and research of Phyto Studio, a Washington, D.C. based studio. The methods build on work described in the author’s book, Planting in a Post-Wild World, an exploration of how to create designed plant communities. 相似文献
5.
Deicing technicians working from open baskets are exposed to ergonomic risks and fatigue. This study aims to assess the global risk of musculoskeletal injuries (MSIs) for this type of activity. An ergonomic study was conducted with the workers of a Canadian airport deicing operator during the winter of 2016–2017. Video recordings made it possible to observe the activities during the most intensive work shifts, as well as characterise and quantify (frequency and duration) the movements/postures of twelve human subjects. The resulting risk assessment identified the body structures submitted to exertion, analysed the efforts involved and globally assessed the forces exerted on the spine and upper limbs. This global risk assessment leads to the conclusion that the risks to the upper limbs are preoccupying and must be examined further. 相似文献
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7.
The economic relationship between China and Myanmar is regarded as a win–win cooperation. However, Chinese investments, especially in extractive and natural resource sectors, are associated with a number of unwanted environmental consequences. Moreover, the environmental impact assessment (EIA) quality of Chinese enterprises has often been criticized. EIA identifies adverse impacts to the environment through evidence-based decision making. On this basis, this paper provides an evaluation of Chinese EIA performance within the natural resources sector through a structured review of 15 environmental impact statements (EISs). This research also evaluates the EISs of the three largest and most controversial projects, the Myitsone Hydropower Dam, Lappadaung Copper Mine and Sino-Myanmar oil and gas pipelines. The findings reveal several omissions, inadequacies and deficiencies in all the projects with a significant number of EISs falling short of satisfactory quality. Through the analysis, the paper summarizes the factors affecting the EIA performance and proposes feasible recommendations to improve EIA practices in Chinese development projects in Myanmar. 相似文献
8.
食品检测为食品安全监管提供技术支撑,是确保食品安全的关键一环,最严谨的标准需要在实验室中科学有效的应用才会更好地服务于最严格的监管。本文主要分析了影响实验室食品检测方法标准实施有效性的因素,剖析了检测过程中人、机、料、法、环、测6个方面可能存在的风险因子,通过风险识别、风险分析评价和风险应对,确保检测方法有效实施和检测数据准确可靠,为监管机构和社会大众提供客观、公正和科学的依据。 相似文献
9.
Yajun Zhang Shan Liu Jing Tan Guoyin Jiang Qing Zhu 《International Journal of Project Management》2018,36(4):627-639
Although business process outsourcing (BPO) can reduce cost and enhance the competitiveness of firms, the implementation of BPO projects is unsatisfactory. By integrating knowledge management capability theory and risk-based view, we develop a model of how different types of BPO risks affect project satisfaction and how knowledge management capability changes the influences of BPO risks. A survey of 121 BPO projects was conducted among BPO client department manager and project manager through a pairwise design. Empirical evidence reveals that social system, technical system, and project management risks negatively affect BPO project satisfaction. However, cultural, technological, and structural levels of knowledge management capabilities weaken the negative risk effects of social system, technical system, and project management, respectively. Different types of risks and knowledge management capabilities should be matched to achieve effective risk management. 相似文献
10.
Wassim Bahr 《国际自然能源杂志》2018,39(8):802-812
This paper assesses building integrated photovoltaic (BIPV) installation parameters based on the profit generated by a photovoltaic system. It takes into consideration a home building case study and it investigates its monthly energy demand based on a specific location and a typical occupancy. The capability of a photovoltaic (PV) system to generate more profit occurs when solar intensity is maximum while the electric energy price is at its highest rate. The paper traces a framework that encompasses different aspects such as energy demand, energy price, and solar intensity. This framework identifies profit alternatives according to different installation parameters. A tool that predicts a PV installation hourly electric energy production is developed. The profit generated is simulated for home buildings located in Beirut (Lebanon) and Xihua (China), both at 33.8° latitude north. The paper highlights a new approach for BIPV installations, taking into account weather conditions, energy demand, and electric energy utility rates. 相似文献