35 research outputs found

    Self-Calibrating, Fully Differentiable NLOS Inverse Rendering

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    Existing time-resolved non-line-of-sight (NLOS) imaging methods reconstruct hidden scenes by inverting the optical paths of indirect illumination measured at visible relay surfaces. These methods are prone to reconstruction artifacts due to inversion ambiguities and capture noise, which are typically mitigated through the manual selection of filtering functions and parameters. We introduce a fully-differentiable end-to-end NLOS inverse rendering pipeline that self-calibrates the imaging parameters during the reconstruction of hidden scenes, using as input only the measured illumination while working both in the time and frequency domains. Our pipeline extracts a geometric representation of the hidden scene from NLOS volumetric intensities and estimates the time-resolved illumination at the relay wall produced by such geometric information using differentiable transient rendering. We then use gradient descent to optimize imaging parameters by minimizing the error between our simulated time-resolved illumination and the measured illumination. Our end-to-end differentiable pipeline couples diffraction-based volumetric NLOS reconstruction with path-space light transport and a simple ray marching technique to extract detailed, dense sets of surface points and normals of hidden scenes. We demonstrate the robustness of our method to consistently reconstruct geometry and albedo, even under significant noise levels

    Enhanced Visible Light Absorption by 3C-SiC Nanoparticles Embedded in Si Solar Cells by Plasma-Enhanced Chemical Vapor Deposition

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    Solar cells with 3C-SiC nanoparticles embedded in the Si were investigated by plasma-enhanced chemical vapor deposition. Several sizes of SiC nanoparticles were used as the intermediate layer for the solar cell. The Si thin films showed the formation of micro- and nanocrystallites on the SiC nanoparticle sites, which play an important role of heating block as a nanosubstrate. The Raman spectra revealed that the SiC nanoparticles were embedded in mixed phases of amorphous and nanocrystalline Si. Compared to the conventional solar cell sample, the photoreflectance was significantly reduced in the UV/visible spectral region due to the presence of the embedded 3C-SiC nanoparticles. The Si nanocrystals formed by the thin film deposition played an important role in reducing the photoreflectance within the visible to infrared spectral zones. Furthermore, the SiC nanoparticles contributed less in the photoabsorption at a longer infrared spectral zone wavelength of 1200ā€‰nm

    A Study on the Improvement of Legal System for Collecting and Registering National R and D Reports

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    A R and D report, which is the result of national research and development project of each government ministry, has a characteristic as a public knowledge-based asset. So it is used with various systems for disclosing and expanding its outcome to the public. In fact, however, systematically collecting and utilizing its related information in KISTI, Korea Institute of Science and Technology Information(National RandD Reports Registration and Administration Agency), is insufficient. Formal regulation for submitting and registering national RandD reports to KISTI, which is wholly responsible for circulating national RandD information, has been arranged well so far. However, specific and concrete regulation system is not enough to make sure of their actual submission and registration. Therefore, this study examines and proposes a specific improvement plan for making good progress of collecting and registering national RandD reports at country levels. Also, it examines improvement methods for standardizing national RandD report style and applying for it, in order to increase work efficiency in submitting and registering the information of national RandD reports.Includes: Conference preprint, Powerpoint presentation, Abstract and Biographical notesXAInternationa

    CAPNet: An Enhanced Load Balancing Clustering Algorithm for Prolonging Network Lifetime in WSNs

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    A wireless sensor network consisting of resources, size, and cost-limited sensors is used in many military and civil applications. This paper proposes an energy-efficient clustering algorithm that extends the lifetime of sensor networks. The proposed clustering algorithm is an extended hierarchical clustering protocol that minimizes the overall amount of consumed energy in the network. The proposed approach dynamically updates clusters and distributes the load on the heavily loaded cluster heads among different nodes. It also balances the remaining energy on nodes in the network, which leads to prolonged network lifetime. The performance is evaluated in terms of network lifetime, average energy consumption, and standard deviation of residual energy

    Feature Selection for Clustering - A Filter Solution

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    Processing applications with a large number of dimensions has been a challenge to the KDD community. Feature selection, an effective dimensionality reduction technique, is an essential pre-processing method to remove noisy features. In the literature there are only a few methods proposed for feature selection for clustering. And, almost all of those methods are `wrapper' techniques that require a clustering algorithm to evaluate the candidate feature subsets. The wrapper approach is largely unsuitable in real-world applications due to its heavy reliance on clustering algorithms that require parameters such as number of clusters, and due to lack of suitable clustering criteria to evaluate clustering in different subspaces. In this paper we propose a `filter' method that is independent of any clustering algorithm. The proposed method is based on the observation that data with clusters has very different point-to-point distance histogram than that of data without clusters. Using this we propose an entropy measure that is low if data has distinct clusters and high otherwise. The entropy measure is suitable for selecting the most important subset of features because it is invariant with number of dimensions, and is affected only by the quality of clustering. Extensive performance evaluation over synthetic, benchmark, and real datasets shows its effectiveness

    Current status and issues in collection and dissemination of national technical reports in Korea

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    ė…øķŠø : Twelfth International Conference on Grey Literature ķ–‰ģ“ģ†Œģš”ģ‹œź°„ : 19:4

    Co-Creation for Social Innovation in the Ecosystem Context: The Role of Higher Educational Institutions

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    This study examined the role of Higher Educational Institutions (HEIs) in promoting, creating, and sustaining social innovation. Recently, HEIs have extended their contribution beyond the traditional function of teaching and research to perform in socio-economic problem-solving. Considering the increasing trends of higher education involvement in social innovation practices, this study tries to examine the tools such as learning processes and systemic thinking approach that could be helpful to align the function and responsibilities of HEIs towards social innovation. The objective is to develop a theoretical understanding of the “co-creation for social innovation” concept and to understand the functions and activities of HEIs that can contribute to this process. To promote co-creation for social innovation, HEIs should actively encourage collaborative learning tools that focus on open platforms for collective action and systemic change that help them to engage with society and strengthen their collaboration with social actors. Different activities such as mutual learning and knowledge diffusion using a transdisciplinary approach, technology-based learning and collaboration, and relational transformation are key enablers that can promote social innovation

    Analysis of Collection and management of the Korea National RandD Report

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    The term ā€˜National R AND D Programā€™ has been widely used in a Korean society, but it is quite new as a legal term. Recently, its legal concept from the perspective of the unified semantics was defined, and the regulation on its scope has been established. In particular, ā€˜National R AND D Programā€™ was officially used as a legal term for the first time in ā€˜Special Act on Innovation in Science and Technology (No. 5340) enacted in April 1997. In the Regulation on the Management of National R AND D Programs, ā€˜National R AND D Programā€™ is defined in Article 2 as follows: ā€œAn R AND D program in science and technology, in which a certain R AND D project is chosen and partially or wholly funded by the government or public organization in accordance with the related law. It refers to all programs except for the basic programs promoted by government-funded research institutes in accordance with Paragraph 1 of Article 2 of Act on the Establishment, Operation and Fostering of Government-funded Research Institutesā€. In particular, because the national R AND D report, one of intangible research outcomes among national R AND D programs, contains important matters on R AND D such as R AND D method and results, it is the final outcome of the national R AND D program regardless of its type. Since it is the evaluation standard of the R AND D project and major research outcome as the final outcome which takes place at the end of the R AND D program, the systematic management of related information is especially important. In this sense, the establishment of the information distribution system which makes it possible to collect, manage and use national R AND D reports has been perceived as one of the most important R AND D policies in any country. In fact, each country has systematically managed related duties through a national science and technology information agency. After all, the management of national R AND D reports is a critical part in the management of the research outcomes of national R AND D programs. This study examines the trend of national R AND D report production, progress and assignment of national R AND D programs and current non-disclosure reports, investigates the current collection and management of national R AND D reports by the KISTI, a professional R AND D report management agency in Korea, and proposes a future direction. In addition, the development of an information distribution system and database for national R AND D reports and online services are analyzed.Includes: Conference preprint, Powerpoint presentation, Abstract and Biographical notesXAInternationa
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