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A knowledge graph and service for regional geologic time standards
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作者 Chao Ma Amruta Suresh Kale +1 位作者 Jiyin Zhang Xiaogang Ma 《Geoscience Frontiers》 SCIE CAS CSCD 2023年第5期334-342,共9页
Geologic time is an important dimension in geological research.Geologic time data are commonly collected from multiple sources in data-intensive studies of Earth’s history and raise an issue of data cleansing and int... Geologic time is an important dimension in geological research.Geologic time data are commonly collected from multiple sources in data-intensive studies of Earth’s history and raise an issue of data cleansing and integration.A knowledge graph of the international geological time scale has been established to harmonize heterogeneous data to facilitate effective and efficient data-driven discovery.Although many regional geologic time standards are also used in various databases and literature,there is limited discussion or development of knowledge graph for them.In this research,we construct a knowledge graph for the geologic time standards in 17 regions at the Epoch and Age levels.This regional geologic time knowledge graph is integrated with the international geologic time knowledge graph as a comprehensive deep-time knowledge base.A SPARQL endpoint has been established to provide open and free online service to the knowledge base.Several use cases are presented here to demonstrate the functionality of the knowledge graph we built as well as its application in open data exploration.Our work addresses the shortage of machine-readable knowledge graphs for regional geologic time standards and will help accelerate geologic data integration from multiple sources in data-intensive studies.All data and code in this paper are made open source and are accessible on GitHub and Zenodo. 展开更多
关键词 Knowledge graph Regional geologic time standard ONTOLOGY Semantic technology
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China National Standards on Nano-Materials Issued for the First Time
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《China Standardization》 2005年第2期4-5,共2页
On February 28th, 2005, AQSIQ (the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China), and SAC (the Standardization Administration of P. R. China)jointly ho... On February 28th, 2005, AQSIQ (the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China), and SAC (the Standardization Administration of P. R. China)jointly hosted the press conference on seven items of national standards on nano-materials in Beijing. The seven items of national standards were approved on Sept. 29th and Dec. 27th, 2004 respectively by SAC, and publicized in Jan. 2005. They will be formally put into practice from April 1st, 2005. 展开更多
关键词 NANO China National standards on Nano-Materials Issued for the First time
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The time and frequency standard system for FAST receivers 被引量:1
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作者 Kai Zhu Jin Fan +16 位作者 Kun Liang Wei Tang Zhi-Sheng Gao Yan Zhu Yi Feng Wei-Wei Zhu Lei Qian You-Ling Yue Jin-You Song Xiang-Wei Shi Xing-Yi Wang Ming-Lei Guo Hang Zhang Heng-Qian Gan Hong-Fei Liu Cheng-Jin Jin Peng Jiang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2020年第5期148-154,共7页
This paper reports on the time and frequency standard system for the Five-hundred meter Aperture Spherical radio Telescope(FAST),including the system design,stability measurements and pulsar timing observations.The st... This paper reports on the time and frequency standard system for the Five-hundred meter Aperture Spherical radio Telescope(FAST),including the system design,stability measurements and pulsar timing observations.The stability and drift rate of the frequency standard are calculated using 1-year monitoring data.The UTC-NIM Disciplined Oscillator(NIMDO)system improves the system time accuracy and stability to the level of 5 ns.Pulsar timing observations were carried out for several months.The weighted RMS of timing residuals reaches the level of less than 3.0μs. 展开更多
关键词 FAST:radio telescope time frequency standard NIMDO:UTC-NIM
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A Computer Vision-Based Model for Automatic Motion Time Study
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作者 Jirasak Ji Warut Pannakkong Jirachai Buddhakulsomsiri 《Computers, Materials & Continua》 SCIE EI 2022年第11期3557-3574,共18页
Motion time study is employed by manufacturing industries to determine operation time.An accurate estimate of operation time is crucial for effective process improvement and production planning.Traditional motion time... Motion time study is employed by manufacturing industries to determine operation time.An accurate estimate of operation time is crucial for effective process improvement and production planning.Traditional motion time study is conducted by human analysts with stopwatches,which may be exposed to human errors.In this paper,an automated time study model based on computer vision is proposed.The model integrates a convolutional neural network,which analyzes a video of a manual operation to classify work elements in each video frame,with a time study model that automatically estimates the work element times.An experiment is conducted using a grayscale video and a color video of a manual assembly operation.The work element times from the model are statistically compared to the reference work element time values.The result shows no statistical difference among the time data,which clearly demonstrates the effectiveness of the proposed model. 展开更多
关键词 Motion time study computer vision convolutional neural network manual operation standard time
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Estimation of Standard Operation Time of Flight Legs Based on Clustering and Probability Analysis
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作者 Yuan Ligang Hu Minghua +1 位作者 Xie Hua Li Yinfeng 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2016年第4期491-501,共11页
A clustering algorithm and a probability statistics method were applied to different phases of a flight to analyze operation time during aircraft ground taxiing and airborne flight.And the clustering pattern,distribut... A clustering algorithm and a probability statistics method were applied to different phases of a flight to analyze operation time during aircraft ground taxiing and airborne flight.And the clustering pattern,distribution characteristics and dynamically changing rules of the two phases were identified.Further,an estimate method was established to measure operation time of flight legs,with creative steps of calculating individual segment separately and then integrating them accordingly.The method can both objectively and dynamically measure operation time,and accurately reflect real situation.It helps to better utilize airport slot resources and provides a strong support for air traffic flow management when scheduling flight plan in strategic and pre-tactic phases. 展开更多
关键词 flight leg standard operation time CLUSTERING probability analysis
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The Principle and Reflection on Determining the Mails' Whole Delivery Standard of Time Bound in the Postal Central Office System 被引量:3
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作者 WANG Wei min, WU Hong bin (Department of Postal Communication Management, Shijiazhuang Postal College, Shijiazhuang 050021,P.R.China) 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2001年第2期61-65,共5页
This paper analyzes some problems arising in determining the mails Whole Delivery Standard of Time Bound ( WDSTB ) at present, and further on the basis of the postal central office system currently in practice, puts... This paper analyzes some problems arising in determining the mails Whole Delivery Standard of Time Bound ( WDSTB ) at present, and further on the basis of the postal central office system currently in practice, puts forward the principle, reflection and the concrete approaches in determining the Delivery Standard of Time Bound ( DSTB ). 展开更多
关键词 whole delivery standard of time bound postal central office system internal handling time bound transportation and Delivery time Bound ( DTB )
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A Pragmatic Approach to Product Costing Based on Standard Time Estimation
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作者 JIAO Yuan-yuan, HAN Wen-xiu, DU JunSchool of Management, Tianjin University, Tianjin 300072, China 《Journal of Systems Science and Systems Engineering》 SCIE EI CSCD 2001年第2期197-202,共6页
The major drawbacks of traditional approaches to product costing include lack of manufacturing knowledge, reliance on the detailed design description, poor cost function approximation and inability to update estimatio... The major drawbacks of traditional approaches to product costing include lack of manufacturing knowledge, reliance on the detailed design description, poor cost function approximation and inability to update estimation algorithms by using actual cost data. Adopting the Activity-Based Costing (ABC) concept and based on estimated processing time, this paper proposes a pragmatic approach to product costing. The approach involves two stages, namely the preparatory stage and the estimation stage. A case study conducted in a refrigerator company is reported. 展开更多
关键词 product costing activity-based costing standard time
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A novel real-time cell electronic analysis technology for the authentication and quality control of natural medicines 被引量:2
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作者 Guo-Jun Yan Xin Mei +3 位作者 Jin Yang Jenny Zhu Jie-Ying Wu Jin-Huo Pan 《Chinese Chemical Letters》 SCIE CAS CSCD 2013年第12期1140-1144,共5页
The study was designed to explore the potential applications of the real-time cell electronic analysis technology in the quality evaluation of natural medicines. The natural medicinal Flos Carthami was discussed as a ... The study was designed to explore the potential applications of the real-time cell electronic analysis technology in the quality evaluation of natural medicines. The natural medicinal Flos Carthami was discussed as a methodological example and the specific time/dose-dependent cell response profiles (TCRPs) were produced by the real-time cell electronic analysis technology. The similarity and bioactivity were obtained by analyzing all TCRPs. Meanwhile, an HPLC method according to the Chinese Pharmacopeia (edition 2010) was used to evaluate the quality of Flos Carthami. The correlation was obtained by comparing the results produced by the two different approaches. By analyzing the data, five different samples ofFlos Carthami can produce remarkably similar TCRPs. The quality ofFlos Carthami was evaluated by both the HPLC and the TCRPs analysis-based approaches and similar results were obtained. The results suggest that the same natural medicine from different locations could produce similar TCRPs. By analyzing the TCRPs, the bioactivity and quality evaluation of natural medicines can be obtained. This technology is a physiologically relevant approach for the quality evaluation of natural medicines. The ultimate aim of our study is to establish a new standard for quality evaluation. 展开更多
关键词 time]dose-dependent cell response profiles (TCRPs) Quality standard Bioactivity Physiologically relevant approach Flos Carthami
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