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국가R&D정보활용을 위한 전문용어사전 구축
No full text국가연구개발(R&D, Research and Development) 정보는 국가 정부부처로부터 발주되는 사업‧과제를 바탕으로 R&D를 수행하는 과정에서 발생되는 정보들로, 다양한 부처에서 발주되는 만큼 다양한 연구분야의 정보들이 포함되어 있다. 따라서 효율적인 R&D정보 검색을 위해서는 이러한 국가R&D정보의 특성을 반영할 수 있는 국가R&D용어사전 구축이 필요하다. 본 연구에서는 국가R&D정보에서 연구분야를 명시하기 위해 활용되는 과학기술표준분류를 적용하여 국가R&D용어사전을 구축하기 위한 방안을 제안한다. 국가R&D 과제정보의 구조적 특성과 그에 따른 과제 키워드의 유용성에 대해 언급하고, 과학기술표준분류별 국가R&D정보 현황과 국가R&D 용어의 특성에 대해 살펴보고자 한다. 그리고 이를 바탕으로 국가R&D용어사전을 구축하기 위한 방법을 용어사전의 유형과 구조, 사전구축 절차, 정제규칙의 관점에서 정의한다. 본 연구를 기반으로 구축되는 국가R&D용어사전은 국가R&D정보 검색 시 한‧영 대역어, 동의어 등을 활용한 검색어 확장과 과학기술표준분류를 활용한 검색 범위 명확화, 용어설명 정보를 활용한 이용자 편의기능 제공 등에 다양하게 활용될 수 있다
Passive microwave precipitation retrieval algorithm using a priori databases with various cloud microphysics schemes: Tropical cyclone applications
No full textThe accuracy of a physically based passive microwave precipitation retrieval algorithm is affected by the quality of the a priori knowledge it employs, which indicates the relationship between the precipitation information obtained from cloud-resolving models (CRMs) and the simulated brightness temperatures (TBs) from radiative transfer models. As various microphysical assumptions reflecting a wide variety of sophisticated microphysical properties are applied to the CRMs, the TBs simulated based on the model-driven 3-D precipitation fields are determined by the selected microphysical assumption. In this article, we developed a prototype precipitation retrieval algorithm that incorporates various cloud microphysics schemes in its a priori knowledge (i.e., databases). In the retrieval process, a specific a priori database is selected for every target precipitation scene by comparing the similarities of the simulated and observed microwave emission and scattering signatures. The prototype algorithm was tested through application to precipitation retrieval for tropical cyclones at various intensity stages, which occurred over the northwestern Pacific region in 2015. The a priori databases constructed using the weather research and forecasting double-moment (WDM6) and Thompson Aerosol Aware schemes are superior when used for weak-to-moderate rainfall systems, whereas the databases constructed with the other schemes are superior within strong rain rate regions. The retrieval results obtained using the best-performing database are generally superior for all rain rate regions. Furthermore, we confirm that the database quality is more important than the number of databases. In comparison with the data from the dual-precipitation radar, the retrieval's correlations, bias, and root mean square are 0.75, 0.14, and 5.62, respectively
DistME: A Fast and Elastic Distributed Matrix Computation Engine using GPUs
No full textMatrix computation, in particular, matrix multiplication is time-consuming, but essentially and widely used in a large number of applications in science and industry. The existing distributed matrix multiplication methods only focus on either low communication cost (i.e., high performance) with the risk of out of memory or large-scale processing with high communication overhead. We propose a distributed elastic matrix multiplication method called CuboidMM that achieves both high performance and large-scale processing. We also propose a GPU acceleration method that can be combined with CuboidMM. CuboidMM partitions matrices into cuboids for optimizing the network communication cost with considering memory usage per task, and the GPU acceleration method partitions a cuboid into subcuboids for optimizing the PCI-E communication cost with considering GPU memory usage. We implement a fast and elastic matrix computation engine called DistME by integrating CuboidMM with GPU acceleration on top of Apache Spark. Through extensive experiments, we have demonstrated that CuboidMM and DistME significantly outperform the state-of-the-art methods and systems, respectively, in terms of both performance and data size
Design and implementation of initial OpenSHMEM on PCIe NTB based cloud computing
No full textCloud computing services are provided by key roles of data centers in which homogeneous and heterogeneous computation nodes are connected by high speed interconnection network. The rapid development of cloud-based services and applications has made data center networks more difficult. The PCI Express is a widely used system bus technology that connects processors and peripheral I/O devices. So, the PCI Express is regarded as a de-facto standard in system area interconnection network. It is currently validating the possibility of using PCI Express as a system interconnection network in areas such as high-performance computers and cluster/cloud computing. With the development of PCI Express non-transparent bridge (NTB) technology, the PCI Express has become available as a system interconnection network. NTB allows two PCI Express subsystems to be interconnected and, if necessary, isolated from each other. Partitioned global address space (PGAS) is one of the shared address space programming models. Due to the recent spread of multicore processors, PGAS has been attracting attention as a parallel computing framework. We make use of the PCI Express NTB to realize the PGAS shared address space model. In this paper, we designed and implemented the interconnection network using PCI Express x8 using a RDK, the PEX8749 based PCI Express evaluation board. We performed some Openshmem applications from Github to verify the accuracy of our initial OpenSHMEM API implementation
압축과 휨을 동시에 받는 케이블교량용 광폭 강박스거더의 강도상호작용
No full text이 연구에서는 압축과 휨을 동시에 받는 케이블교량용 광폭 강박스거더에 대한 Eurocode 3 및 AASHTO LRFD의 강도상호작용식의 적용가능성을 검토한다. 범용 구조해석프로그램을 이용하여 기시공된 사장교의 광폭 강박스거더의 한 부분을 유한요소로 모델링하고, 기하학적 초기결함과 잔류응력이 고려된 극한강도해석을 수행한다. 압축강도와 휨강도를 각각 도출한 후, 서로에 대한 각각의 강도저하 영향을 확인하기 위한 극한강도 상호작용거동을 도출한다. 광폭 강박스거더에 대한 압축과 휨에 의한 강도상호작용은 AASHTO LRFD보다는 Eurocode 3의 상호작용식을 적용하는 것이 안전측인 것으로 확인되었다
Social Media News in Crisis? Popularity Analysis of the Top Nine Facebook Pages of Bangladeshi News Media
Get PDFSocial media has become a popular source of information around the world. Previous studies explored different trends of social media news consumption. However, no studies have focused on Bangladesh to date, where social media penetration is very high in recent years. To fill this gap, this research aimed to understand its popularity trends during the period. For that reason, this work analyzes 97.67 million page likes and 3.48 billion interaction data collected from nine Bangladeshi news media's Facebook pages between December 2016 to November 2020. The analysis shows that the growth rates of page likes and interaction rates declined during this period. It suggests that the media's Facebook pages are gradually losing their popularity among Facebook users, which may have two more interpretations: Facebook's aggregate appeal as a news source is decreasing to users, or Bangladeshi media's appeal is eroding to Facebook users. These findings challenge the previous results, i.e., Facebook's demand as a news source is increasing with time. We offer four explanations of the decreased popularity of Facebook's news: information overload, exposure to incidental news, users' selective exposure and different aims of using Facebook, and conflict between media agendas and users' interests. Some theoretical and practical significance of the results has been discussed as well
Developing an Improved Risk-Adjusted Net Present
No full textThe financial valuation of a drug that is still under development is required for various purposes. The risk-adjusted net present value (r-NPV) method, which recently emerged in the biotech industry, uses the development attrition rate as a discount factor to reflect risk during each development phase. The r-NPV method was developed to overcome the disadvantages of the prevailing discounted cash flow and real options methods and considers drug type, as well as the stage of development in its approach. Using this method, the current study examines technology values in the biopharmaceutical industry and matches the clinical development periods and success rates of these new drugs by analyzing datasets from ClinicalTrials.gov and MedTrack DB. It thus provides support for an empirical valuation model for experts in the field. Notably, there is limited research on the attrition rate and development period of new substance drugs and the research results are not consistently presented. In addition to new substance drugs, further research is necessary to deepen understanding of the attrition rate and development period of biologically-based drugs because of their inherent physical and developmental differences. Similarly, research on performance specifics within drug class models would enable refinement of the model
KCI vs. WoS: Comparative Analysis of Korean and International Journal Publications in Library and Information Science
Get PDFThe study analyzed bibliometric data of papers published in Korea Citation Index (KCI) and Web of Science (WoS) journals from 2002 to 2021. After examining size differences of KCI and WoS domains in the number of authors, institutions, and journals to put publication and citations counts in perspective, the study investigated co-authorship patterns over time to compare collaboration trends of Korean and international scholars and analyzed the data at author, institution, and journal levels to explore how the influences of authors, institutions, and journals on research output differ across domains. The study also conducted frequency-based analysis of keywords to identify key topics and visualized keyword clusters to examine topic trends. The result showed Korean LIS authors to be twice as productive as international authors but much less impactful and Korean institutions to be at comparable levels of productivity and impact in contrast to much of productivity and impact concentrated in top international institutions. Citations to journals exhibited initially increasing pattern followed by a decreasing trend though WoS journals showed far more variance than KCI journals. Co-authorship trends were much more pronounced among international publication, where larger collaboration groups suggested multi-disciplinary and complex nature of international LIS research. Keyword analysis found continuing diversification of topics in international research compared to relatively static topic trend in Korea. Keyword visualization showed WoS keyword clusters to be much denser and diverse than KCI clusters. In addition, key keyword clusters of WoS were quite different from each other unlike KCI clusters which were similar