Dataspace is a semi-structural data model for the management of large-scale heterogeneous data *** a dataspace,each data object consists of a set of attribute-value pairs to describe the internal properties of the obj...
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Dataspace is a semi-structural data model for the management of large-scale heterogeneous data *** a dataspace,each data object consists of a set of attribute-value pairs to describe the internal properties of the object and their relationships to other objects. The dataspace model provides a flexible query language that supports attribute-value pair-based predicate queries and semantic link queries. In this paper we introduce a Resource Space Model that extends the concepts of dataspace to make it more flexible by incorporating classification semantics. We model a dataspace as a set of Resource Spaces (RS) with each RS representing a kind of resources that share common attributes and can be put into the same category, either according to a user’s knowledge of the world or his query preferences. Our model is suitable for designing a user-tailored semantic view of a dataspace while at the same time without losing the schema-later data-centric nature. A practical query language is introduced to implement flexible query operations on the resource spaces of the dataspace. Examples show how the proposed model and language support both the schema query and the data query.
作者:
Chen, JingqiangZhuge, HaiNanjing University of Posts and Telecommunications
210023 Nanjing China. Key Lab of Intelligent Information Processing Institute of Computing Technology University of Chinese Academy of Sciences 100190 Beijing China. Systems Analytics Research Institute Aston University Birmingham UK
Automatically generating the related work section for a writing paper is useful for researchers as it can save a lot of time and avoid missing related works. The related work section of scientific paper usually introd...
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Two-dimensional platinum diselenide (PtSe_(2)) has been explored for applications in visible and infrared photodetectors, owing to its tunable electrical and optoelectronic properties governed by layer-dependent bandg...
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Two-dimensional platinum diselenide (PtSe_(2)) has been explored for applications in visible and infrared photodetectors, owing to its tunable electrical and optoelectronic properties governed by layer-dependent bandgaps. Studies have explored both positive photoconductivity (PPC) and negative photoconductivity (NPC) behaviors in few-layer PtSe_(2) thin films, proposing mechanisms related to gas molecule adsorption. However, these proposed mechanisms, typically based on models with ideal limit structures, often lacked consistency with the structure and scale of polycrystalline thin films employed in actual experiments. Here, photodetectors utilizing monolayer PtSe_(2) ribbons were designed, demonstrating a significant NPC effect upon exposure to visible light in atmospheric conditions, with device resistance increasing to over threefold the initial state. Under vacuum conditions, the device demonstrated PPC characteristics. Density functional theory calculations indicated that oxygen molecules physically adsorbed at the edges of PtSe_(2) ribbons were integral. Laser irradiation prompted the detachment of oxygen molecules from the ribbon’s edges, leading to a decreased carrier concentration in channel conductivity. The abundant edge sites of the ribbons endowed the photodetectors with a pronounced NPC response. This study diverted from traditional multilayer PtSe_(2) films to explore monolayer PtSe_(2) ribbons. These ribbons, as limit structures, offered a more fundamental insight into the intrinsic photoconductivity properties of PtSe_(2). Photodetectors employing PtSe_(2) ribbons presented novel application prospects in low-power photodetection, gas detection, and additional fields.
Jointly parsing two languages has been shown to improve accuracies on either or both sides. However, its search space is much bigger than the monolingual case, forcing existing approaches to employ complicated modelin...
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Face alignment or facial landmark detection plays an important role in many computer vision applications, e.g., face recognition, facial expression recognition, face animation, etc. However, the performance of face al...
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ISBN:
(纸本)9781467388528
Face alignment or facial landmark detection plays an important role in many computer vision applications, e.g., face recognition, facial expression recognition, face animation, etc. However, the performance of face alignment system degenerates severely when occlusions occur. In this work, we propose a novel face alignment method, which cascades several Deep Regression networks coupled with De-corrupt Autoencoders (denoted as DRDA) to explicitly handle partial occlusion problem. Different from the previous works that can only detect occlusions and discard the occluded parts, our proposed de-corrupt autoencoder network can automatically recover the genuine appearance for the occluded parts and the recovered parts can be leveraged together with those non-occluded parts for more accurate alignment. By coupling de-corrupt autoencoders with deep regression networks, a deep alignment model robust to partial occlusions is achieved. Besides, our method can localize occluded regions rather than merely predict whether the landmarks are occluded. Experiments on two challenging occluded face datasets demonstrate that our method significantly outperforms the state-of-the-art methods.
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It has become a challenging work to collect valuable information from fast text streams. In this work, we propose a method which gains useful information effectively and efficiently. Firstly, we maintain an analyzer b...
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Infrared target detection is currently widely used in both military and civilian fields. Due to the lower resolution of infrared images compared to visible light images and the lack of texture information in small tar...
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An iterative algorithm is presented for the frequency recovery of the band-limited seismic data based on the sparse spike train deconvolution (SSTD) method using the minimum entropy criterion. In this method, we explo...
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