Subjects: Nuclear Science and Technology >> Nuclear Detection Technology and Nuclear Electronics submitted time 2024-05-07
Abstract： [Background]: With the deepening of oil and gas exploration, the research on the design and measurement methods of X-ray density logging tools, as a new generation of controllable sources, has attracted widespread attention. [Purpose]: Based on the prototype of ultra-slim gamma logging tool, the gamma source is replaced with an X-ray source. [Methods]: The specific content includes: 1) simulating and matching the energy spectrum of the X-ray source; 2) comprehensively guiding the forward design of the key parameters of the tool through indicators such as detection efficiency, formation sensitivity, and detection depth; 3) conducting X-ray density measurements based on the multivariate forward and inverse modeling method, and comparing them with gamma density logging results. [Results]: The results show that when the short and long-spaced detectors’ source distances of the X-ray tool are set to 110mm and 290mm, it can achieve comparable or even higher detection indicators compared to gamma tool. Compared with gamma logging, X-ray logging has better formation sensitivity, vertical resolution, and formation measurement accuracy. The formation density and Pe are within 0.015g/cm3 and 0.2b/e, respectively. Especially in the barite mudcake scenario, the accuracy of Pe measurement has been improved by 47%. [Conclusions]: These studies provide reference for tool forward design and X-ray density measurement.
Subjects: Nuclear Science and Technology >> Nuclear Detection Technology and Nuclear Electronics submitted time 2024-05-06
Abstract： [Background]: With the deepening of oil and gas exploration, the research on the design and measurement methods of X-ray density logging tools, as a new generation of controllable sources, has attracted widespread attention. [Purpose]: Based on the prototype of ultra-slim gamma logging tool, the gamma source is replaced with an X-ray source. [Methods]: The specific content includes: 1) simulating and matching the energy spectrum of the X-ray source; 2) comprehensively guiding the forward design of the key parameters of the tool through indicators such as detection efficiency, formation sensitivity, and detection depth; 3) conducting X-ray density measurements based on the multivariate forward and inverse modeling method, and comparing them with gamma density logging results. [Results]: The results show that when the short and long-spaced detectors’ source distances of the X-ray tool are set to 110mm and 290mm, it can achieve comparable or even higher detection indicators compared to gamma tool. Compared with gamma logging, X-ray logging has better formation sensitivity, vertical resolution, and formation measurement accuracy. The formation density and Pe are within 0.015g/cm3 and 0.2b/e, respectively. Especially in the barite mudcake scenario, the accuracy of Pe measurement has been improved by 47%. [Conclusions]: These studies provide reference for tool forward design and X-ray density measurement.
Subjects: Management Science >> Science ology and Management submitted time 2023-07-09 Cooperative journals: 《中国科学院院刊》
Abstract： Open science is thriving and driving a global paradigm shift in scientific research. Open science governance is designated to gradually increase the transparency and global participation in the process of scientific and technological progress, ensure low-cost openness around the world, accelerate the global dissemination and sharing of results, and improve the scientific and humanistic literacy of the people. With the development trend of open science becoming more and more powerful, a series of challenges emerge gradually. By analyzing and studying the open science governance framework model, it helps to further sort out the governance logic, clarify the governance subjects and governance mechanisms, which will effectively promote the construction of open science governance system, accelerate the development of science and technology, help China become one of the leaders of the global knowledge community in 2040–2050, and promote the realization of the strategic goal of becoming a world power in science and technology.
Subjects: Physics >> Nuclear Physics submitted time 2023-06-06
Abstract： Accurate 3-Dimensional (3-D) reconstruction technology for non-destructive testing based on digital radiography (DR) is of great importance for alleviating the drawbacks of the existing computed tomography (CT)-based method. The commonly used Monte Carlo simulation method ensures well-performing imaging results for DR. However, for 3-D reconstruction, it is limited by its high time consumption. To solve this problem, this study proposes a parallel computing method to accelerate Monte Carlo simulation for projection images with a parallel interface and a specific DR application. The images are utilized for 3-D reconstruction of the test model. We verify the accuracy of parallel computing for DR and evaluate the performance of two parallel computing modes—multithreaded applications (G4-MT) and message-passing interfaces (G4-MPI)—by assessing parallel speedup and efficiency. This study explores the scalability of the hybrid G4-MPI and G4-MT modes. The results show that the two parallel computing modes can significantly reduce the Monte Carlo simulation time because the parallel speedup increment of Monte Carlo simulations can be considered linear growth, and the parallel efficiency is maintained at a high level. The hybrid mode has strong scalability, as the overall run time of the 180 simulations using 320 threads is 15.35 h with 10 billion particles emitted, and the parallel speedup can be up to 151.36. The 3-D reconstruction of the model is achieved based on the filtered back projection (FBP) algorithm using 180 projection images obtained with the hybrid G4-MPI and G4-MT. The quality of the reconstructed sliced images is satisfactory because the images can reflect the internal structure of the test model. This method is applied to a complex model, and the quality of the reconstructed images is evaluated.
Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-03-28 Cooperative journals: 《中国科学院院刊》
Abstract： The research infrastructure is the basic and strategic platform of scientific and technological innovation. In the last decade, China’s research infrastructure has achieved leapfrog development in the level of observation, manufacturing, management, data acquisition, data sharing and utilization, which supports China’s scientific and technological innovation activities at a higher level. Looking into the future, the scientific research paradigm is transforming. The network, data, and computing platform will not only support the development of major science and technology infrastructure and field stations in larger, more accurate, and more advanced approach, but also contribute to the transformation of scientific research paradigm. It will become an “accelerator” and “multiplier” for major scientific and technological breakthroughs. It is also the key support for China to become the forefront of innovative countries and to enter the world’s science and technology strength.
Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-03-28 Cooperative journals: 《中国科学院院刊》
Abstract： The concept of bionics combines biology and engineering technology to provide people with new principles, methods, and ways to improve and create new equipment, promote technological innovation, and solve technical problems in the most flexible, efficient, reliable, and economical way. Although information technology continues to develop, it still faces many challenges in the era of big data and intelligence. With the explosive growth of massive data, the demand of storage, calculation, and analysis, and its energy consumption and efficiency challenges, information technology is urgently needed to find a new development direction. Inspired by biotechnology, it is becoming an international frontier research direction to find information technology innovation scheme from biological structure. As active new research fields, DNA data storage and neural morphological computation as well as related research are representative directions, which have broad future development prospects. Based on the development status and trend of these two research directions, this study attempts to analyze the motivation, trend, and prospect of information technology development inspired by biotechnology. The next two decades will be an important time window for the cross integration of life field and information field. By learning and simulating from life system, and drawing on the new ideas, principles and theories provided by biotechnology research, the information field will produce a number of subversive technologies and applications, and it will affect the entire academic and industrial sessions.
Subjects: Medicine, Pharmacy >> Clinical Medicine submitted time 2022-11-23 Cooperative journals: 《中国全科医学》
Abstract：
In-depth interview is to understand the experience and lifestyle of a certain social group through in-depth conversation with the respondents, explore the formation process of specific phenomena, and put forward ideas and recommendations to solve problems. In-depth interview has been widely used in the study of primary care research. Thus, understanding its basic concept and mastering the design and application process is essential to master this method. This paper comprehensively expounds the process of the three stages of implementing in-depth interview research. Before formally carrying out in-depth interview research, researchers need to understand its basic concepts, characteristics and limitations related to the research purpose and process, and identify which studies are applicable if using this method. In the design and implementation of in-depth interview research, researchers should focus on the main steps of the research in four stages: recruitment of interviewees, design and modification of interview guide, collection of interview data, and analysis of interview data. After completing the data analysis of the in-depth interview, researchers need to write a research paper referring to criteria or standards of qualitative research to increase the credibility of research results and the transparency of the research process. In addition, this paper recommends five fields suitable for in-depth interviews in primary care research, and introduces learning resources for researchers to master in-depth interview methods. Through the introduction of in-depth interview research method, this paper aims to help researchers in the field of general practice/primary care to master a method suitable for scientific research, and provide methodology reference for improving the quality of qualitative research in this field in China.
Subjects: Biology >> Botany submitted time 2022-09-08 Cooperative journals: 《广西植物》
Abstract： Pimpinella candolleana is known as Miao ethnic herbal medicine in Guizhou for the treatment of icteric hepatitis, acute cholecystitis and other diseases. To investigate the chemical constituents of P. candolleana and their anti-inflammatory activities, the chemical constituents from the 70% ethanol extract of P. candolleana were separated by silica gel, Sephadex LH-20, Toyopearl HW-40F, Toyopearl HW-40C, ODS and other column chromatography, and their structures were elucidated by extensive spectroscopic analysis such as nuclear magnetic resonance (NMR) and mass spectrum (MS). The inflammatory cell model, built by LPS-induced RAW264.7 macrophage cells, was used to evaluate the anti-inflammatory activity. The results were as follows: (1): Detailed phytochemical study on P. candolleana led to the isolation and identification of twenty compounds were including vanillin (1), sesamin (2), 2-methyl-2-hydroxy-5-methoxy berz (d) hydrofuran-3-one (3), procatechin (4), 1,5-dihydroxy-2,3-dimethoxyxanthone (5), isorhamnetin (6), kaempferol (7), 8-hydroxy-2-methylchromone (8), luteolin (9), quercetin (10), 1-O-β-D-glucopyranosyl-(2S,3S,4R,8E)-2-[(2'R)-2'-hydroxypalmitoylamino]-8-octadecene-1,3,4- triol (11), isorhamnetin-3-O-β-D-galactopyranoside (12), isoquercitrin (13), norswertianolin (14), luteolin-6-C-α-L-arabinoside (15), kaempferol-3-O-β-D-galactopyranoside (16), kaempferol-7-O- β-D-glucopyranoside (17), luteolin-7-O-β-D-glucopyranoside (18), isovitexin (19), rutin (20). Compounds 1, 3, 4, 6, 7, 10, 13, 16, 18, and 20 were obtained from this plant for the first time. (2) The anti-inflammatory results showed that compounds 2-10, 12, 18 and 19 could significantly inhibit the LPS-induced NO content in RAW264.7 cells (P<0.05, P<0.01), and the inhibition rates of compounds 4, 7, 10, and 18 at a concentration of 25 μmol·L-1 were 57.37%, 83.60%, 68.16%, 81.14%, respectively. Overall, this study enriches the chemical constituents of P. candolleana, and clarifies that flavonoids are the active ingredients in the course of anti-inflammatory, which may provide a theoretical basis for further research and exploitation of P. candolleana.
Subjects: Medicine, Pharmacy >> Clinical Medicine submitted time 2022-08-17 Cooperative journals: 《中国全科医学》
Abstract： General practice research often pays attention not only to the physical health of patients, professional competence of doctors, and the quality of medical services, but also to the spiritual feelings of patients, motivation of doctors to practice, and the cooperation between doctors and patients. However, these are not resolved well only using quantitative research which is still dominated in the field of general practice. Mixed methods research which integrates qualitative and quantitative research, combining the advantages of both, can analyze specific problems more broadly and in depth, and increase the generalizability of research results, which is suitable for studying complex problems. However, the application of mixed methods research in general practice is still limited in China, and the standardization of its design and implementation needs to be improved. Therefore, this paper plans to introduce the key points in the design and implementation of mixed methods research from methodological lence, combining theory with practice, so as to provide reference for general practitioners who intend to carry out mixed methods research.
Subjects: Biology >> Botany >> Applied botany submitted time 2021-04-29 Cooperative journals: 《广西植物》
Abstract： To study the chemical constituents of China endemic plant Rubia oncotricha, the compounds were isolated and purified by silica gel, ODS, Sephadex LH-20, and their structures were elucidated by modern spectroscopic techniques. Fifteen anthraquinone compounds were isolated and identified from Rubia oncotricha, they are 2-methyl-1,3,6-trihydroxy-9,10-anthraquinone-3-O-(6'-O-acetyl)-α-rhamnosyl(1→2)-β-glucoside (1), 2-methyl-1,3,6-trihydroxy-9,10-anthraquinone-3-O-α-rhamnosyl(1→2)-β-glucoside (2), 2-methyl-1,3,6-trihydroxy-9,10-anthraquinone-3-O-(3'-O-acetyl)-α-rhamnosyl (1→2)-β-glucoside (3), 2-methyl-1,3,6-trihydroxy-9,10-anthraquinone-3-O-β-glucoside (4), 1,3,6-trihydroxy-2-hydroxymethyl-9,10-anthraquinone-3-O-(6'-O-acetyl)-β-D-glucopyranoside (5), 2-methyl-1,3,6-trihydroxy-9,10-anthraquinone-3-O-(6'-O-acetyl)-β-D-glucopyranoside (6), physcion-8-O-β-D-glucopyranoside (7), emodin-8-O-β-D-glucopyranoside (8), digiferruginol-11-O-β-gentiobioside (9), 2-methyl-1,3,6-trihydroxy-9,10-anthraquinone-3-O-(6'-O-acetyl)-β-D-xylopyranosyl-(1→2)-β-Dglucopyranoside (10), 6-hydroxyrubiadin (11), 1,2-dihydroxyanthraquinone (12), chrysophanol (13), 6-hydroxyxanthopurpurin (14), 1,3-dihydroxyanthraquinone (15). Compounds 7, 8, 14 are isolated from the genus of Rubia for the first time, compound 1~6, 9, 10, 12, 13 are isolated from Rubia oncotricha for the first time.
Subjects: Computer Science >> Integration Theory of Computer Science submitted time 2019-01-03 Cooperative journals: 《计算机应用研究》
Abstract： This paper proposed a intrusion detection algorithm based on deep sequence weighting kernel limit learning (DBN-WOS-KELM) to solve the problem of massive multi-source heterogeneous network intrusion detection with unbalanced data distribution and the problem that the traditional deep learning algorithm can not update its output weight online according to the real-time intrusion situation. The algorithm first uses the deep belief network DBN to study the historical data, then extracts the features of the original data and reduces the dimension of the data, and then uses the weighted sequence kernel extreme learning machine for supervised learning to complete the intrusion detection. It combines the ability of extracting Abstract features from the deep belief network and the fast learning ability of the kernel extreme learning machine. Finally, the simulation experiments on KDD99 dataset show that DBN-WOS-KELM algorithm improves the recognition rate of small sample attacks, and can update the output weights online according to the real-time situation, so that the training efficiency is much higher.
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