• Title/Summary/Keyword: flow information

Search Result 5,744, Processing Time 0.036 seconds

Borehole Elemental Concentration Logs: Theory, Current Trends and Next Level (암석구성성분검층: 원리, 연구동향 및 향후 과제)

  • Shin, Jehyun;Hwang, Seho
    • Geophysics and Geophysical Exploration
    • /
    • v.22 no.3
    • /
    • pp.149-159
    • /
    • 2019
  • Borehole elemental concentration logging, measuring neutron-induced gamma rays by inelastic scattering and neutron capture interactions between neutron and formation, delivers concentrations of the most common elements found in the minerals and fluids of subsurface formation. X-ray diffraction and X-ray fluorescence analysis from core samples are traditionally used to understand formation composition and mineralogy, but it represents only part of formations. Additionally, it is difficult to obtain elemental analysis over the whole intervals because of poor core recovery zones such as fractures or sand layers mainly responsible for groundwater flow. The development of borehole technique for in situ elemental analysis plays a key role in assessing subsurface environment. Although this technology has advanced consistently starting from conventional and unconventional resources evaluation, it has been considered as exclusive techniques of some major service company. As regards domestic research and development, it has still remained an unexplored field because of some barriers such as the deficiency of detailed information on tools and calibration facility for chemistry and mineralogy database. This article reviews the basic theory of spectroscopy measurements, system configuration, calibration facility, and current status. In addition, this article introduces the domestic researches and self-development status on borehole elemental concentration tools.

A Study on Smart Soil Resistance Measuring Device for Safety Characterized Ground Design in Converged Information Technology (ICT 융합 환경에서의 안전 특성화 접지 설계를 위한 스마트 대지 저항 측정 기술에 관한 연구)

  • Kim, Hong-Yong;Shin, Seung-Jung
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.19 no.1
    • /
    • pp.203-209
    • /
    • 2019
  • In this work, a new land-specific resistance measuring device (GM) and a measuring probe (Grounding Rod) are connected to the WENNER quadrant as power-line communication (PLC). In groups of two (P1,P2) probes, five to ten probes are installed in series on the ground at intervals of 1m, 2m, 4m, 8m, and 16m, respectively. If the PLC signal from the GMD is detected by the receiver of the Probe 1 (P1) for measurement, the minute voltage and current for measurement flow from the PSD (power supply) attached to the probe to the ground, and then, through the soil between P1 and P2, enters the Probe 1 (P2). The resistance value is then measured by the principle of voltage drop due to ground resistance. Measure the earth resistance every T seconds up to 1 trillion and store the measured data on the Arduino Server mounted on the main equipment. Stored measurement data can be derived from formulas by Ohm's Law and from inherent resistance (here,). Data obtained in real time will be linked to CDGES programs installed on Main PC, enabling data analysis and real-time monitoring of the ground environment on land. In addition, a three-dimensional display is possible with 3D graph support by identifying seasonal characteristics such as temperature and humidity of land (soils). The limitations of the study will require specific application measures of Test Bed for commercial access to a model that has been developed and operated experimentally.

Application of DNA Analysis for Identification of Prey Items on Zooplankton: Selective Treatment Method (기수역 요각류 위내용물 유전자 분석: 소화기관 내외부 유전자의 선택적 처리방법)

  • Chae, Yeon-Ji;Oh, Hye-Ji;Kim, Yong-Jae;Chang, Kwang-Hyeon;Jo, Hyunbin
    • Korean Journal of Ecology and Environment
    • /
    • v.54 no.3
    • /
    • pp.247-256
    • /
    • 2021
  • Understanding the selective feeding behavior of zooplankton on phytoplankton is essential for evaluating the nutrient cycle and energy flow in the food web. Although many studies have been conducted regarding the feeding behaviors of zooplankton through gut content analyses, there are limitations in the visual identification of digested contents using a microscope. DNA techniques have been applied to overcome these limitations since they can detect and amplify small amounts of prey DNA remaining in the gut contents. We designed a method to extract prey DNA from the gut contents of the whole body of the copepod specimen and tested the resolution of DNA identification for the prey phytoplankton. The common brackish species, Sinocalanus tenellus, were collected from Saemangeum Reservoir in different sites and seasons, and gut content DNA was extracted using 2.5% bleach treatment for 2 min for removal of potential contamination sources existing in preserved specimens without dissolution of the body. The sequences of the extracted gut contents were confirmed using BLASTn suite based on the NCBI database. The phytoplankton species detected in the gut showed temporal and spatial differences. Although DNA analysis of small copepod gut contents has been suggested as an effective method to examine the dynamics of primary prey sources at the genus or species level, uncertainties such as misidentification and limitations in the detailed information of the composition still exist.

Application of Remote Sensing Technology for Developing REDD+ Monitoring Systems (REDD+ 모니터링 시스템 구축을 위한 원격탐사기술의 활용방안)

  • Park, Taejin;Lee, Woo-Kyun;Jung, Raesun;Kim, Moon-Il;Kwon, Tae-Hyub
    • Journal of Korean Society of Forest Science
    • /
    • v.100 no.3
    • /
    • pp.315-326
    • /
    • 2011
  • In recent years, domestic and international interests focus on climate change, and importance of forest as carbon sink have been also increased. Particularly REDD+ mechanism expanded from REDD (Reduced Emissions from Deforestation and Degradation) is expected to perform a new mechanism for reducing greenhouse gas in post 2012. To conduct this mechanism, countries which try to get a carbon credit have to certify effectiveness of their activities by MRV (Measuring, Reporting and Verification) system. This study analyzed the approaches for detecting land cover change and estimating carbon stock by remote sensing technology which is considered as the effective method to develop MRV system. The most appropriate remote sensing for detection of land cover change is optical medium resolution sensors and satellite SAR (Synthetic Aperture Radar) according to cost efficiency and uncertainty assessment. In case of estimating carbon stock, integration of low uncertainty techniques, airborne LiDAR (Light Detection and Ranging), SAR, and cost efficient techniques, optical medium resolution sensors and satellite SAR, could be more appropriate. However, due to absence of certificate authority, guideline, and standard of uncertainty, we should pay continuously our attention on international information flow and establish appropriate methods. Moreover, to apply monitoring system to developing countries, close collaboration and monitoring method reflected characteristics of each countries should be considered.

High-density single nucleotide polymorphism chip-based conservation genetic analysis of indigenous pig breeds from Shandong Province, China

  • Wang, Yanping;Zhao, Xueyan;Wang, Cheng;Wang, Wenwen;Zhang, Qin;Wu, Ying;Wang, Jiying
    • Animal Bioscience
    • /
    • v.34 no.7
    • /
    • pp.1123-1133
    • /
    • 2021
  • Objective: Shandong indigenous pig breeds are important Chinese pig resources. Their progressive population decline in recent decades has attracted attention towards their conservation. Conservation genetics of these indigenous breeds are essential for developing a conservation and utilization scheme. Methods: A high-density single nucleotide polymorphism (HD-SNP) chip-based comparative analysis of genetic characteristics was performed for seven Shandong indigenous pig breeds in the context of five Western commercial breeds. Results: The results showed that Shandong indigenous pig breeds varied greatly in genetic diversity, effective population size, inbreeding level, and genetic distance with the Western commercial breeds. Specifically, Laiwu and Dapulian displayed low genetic diversity, and had a genetically distant relationship with the Western commercial breeds (average F statistics [FST] value of 0.3226 and 0.2666, respectively). Contrastingly, the other five breeds (Yantai, Licha, Yimeng, Wulain, and Heigai) displayed high genetic diversity within breed and had some extent of mixture pattern with the Western commercial breeds, especially Duroc and Landrace (FST values from 0.1043 to 0.2536). Furthermore, intensive gene flow was discovered among the seven Shandong indigenous breeds, particularly Wulian, Licha, and Heigai, as indicated by the large cluster formed in the principal component analysis scatterplot and small population differentiation (average of 0.1253) among them. Conclusion: Our study advances the understanding of genetic characteristics of Shandong indigenous breeds and provides essential information for developing an appropriate conservation and utilization scheme for these breeds.

A Study on the Analysis of China's Telemedicine Industry from the Perspective of the Industrial Innovation System and its Implications for Korea (산업혁신체제 관점에서의 중국의 원격의료 산업 분석과 국내로의 함의점 연구)

  • Kim, Mikyung;Zhang, Yi
    • The Journal of the Korea Contents Association
    • /
    • v.21 no.3
    • /
    • pp.441-453
    • /
    • 2021
  • Recently, the untact healthcare industry due to COVID-19 has been attracting attention, and the telemedicine industry based on medical information has become a field of the healthcare industry receiving attention. However, in Korea, due to obstacles in the legal system, telemedicine is still illegal between doctors and patients. In the case of neighboring China, the reality is the opposite of the recent rapid growth of the telemedicine industry under the leadership of the government. This study looks at this from the perspective of the industrial innovation system on the grounds that telemedicine is an industry and innovative technology needs to be changed to clarify the difference between domestic and Chinese telemedicine industries. As a result of analyzing China's telemedicine industry on the seven sub-divisions of demand conditions, innovators, networks et al., Such as seizing appropriate opportunities for demand driving effects and appropriate communication between economic actors were identified as major success factors. This researcher proposes the following suggestions. first, it conforms to the current digital New Deal policy flow, and conducts a demand survey on the change in demand for medical services in the 4th Industrial Revolution and the Untact Era. For the introduction, a plan to conduct a demand survey for the public and second, second, a plan to grow and intensively foster digital high-tech medical care as a new industry was suggested.

A Numerical Study on the Characteristics of Flows and Fine Particulate Matter (PM2.5) Distributions in an Urban Area Using a Multi-scale Model: Part I - Analysis of Detailed Flows (다중규모 모델을 이용한 도시 지역 흐름과 초미세먼지(PM2.5) 분포 특성 연구: Part I - 상세 흐름 분석)

  • Park, Soo-Jin;Choi, Wonsik;Kim, Jae-Jin
    • Korean Journal of Remote Sensing
    • /
    • v.36 no.6_3
    • /
    • pp.1643-1652
    • /
    • 2020
  • To investigate the characteristics of detailed flows in a building-congested district, we coupled a computation fluid dynamics (CFD) model to the local data assimilation and prediction system (LDAPS), a current operational numerical weather prediction model of the Korea Meteorological Administration. For realistic numerical simulations, we used the meteorological variables such as wind speeds and directions and potential temperatures predicted by LDAPS as the initial and boundary conditions of the CFD model. We trilinearly interpolated the horizontal wind components of LDAPS to provide the initial and boudnary wind velocities to the CFD model. The trilinearly interpolated potential temperatures of LDAPS is converted to temperatures at each grid point of the CFD model. We linearly interpolated the horizontal wind components of LDAPS to provide the initial and boundary wind velocities to the CFD model. The linearly interpolated potential temperatures of LDAPS are converted to temperatures at each grid point of the CFD model. We validated the simulated wind speeds and directions against those measured at the PKNU-SONIC station. The LDAPS-CFD model reproduced similar wind directions and wind speeds measured at the PKNU-SONIC station. At 07 LST on 22 June 2020, the inflow was east-north-easterly. Flow distortion by buildings resulted in the east-south-easterly at the PKNU-SONIC station, which was the similar wind direction to the measured one. At 19 LST when the inflow was southeasterly, the LDAPS-CFD model simulated southeasterly (similar to the measured wind direction) at the PKNU-SONIC station.

Review of Earthquake Studies Associated with Groundwater by Korean Researchers (국내 연구진의 지하수를 이용한 지진 연구 동향 분석)

  • Yun, Sul-Min;Hamm, Se-Yeong;Cheong, Jae-Yeol;Lee, Hyun A
    • Journal of the Korean earth science society
    • /
    • v.43 no.1
    • /
    • pp.165-175
    • /
    • 2022
  • Earthquakes have occurred owing to movements on a fault since several billion years ago. Research on the relationship between earthquakes and groundwater began in the 1960s in the United States, but related works, including hydrogeochemistry research, only began in the 2010s in South Korea. In this study, domestic studies on the relationship between earthquakes and groundwater until 2021 were collected from the Web of Science and characterized by subject area (groundwater level, hydrogeochemistry, combination of the two, and others). The results showed that the number of published articles per year was positively correlated with the 2011 Tohoku earthquake, 2016 Gyeongju earthquake, and 2017 Pohang earthquake, with the maximum numbers observed in 2011, 2018, 2019, and 2020. Most studies on the relationship between earthquakes and groundwater level addressed groundwater level fluctuations in the duration of the subject earthquake, with little consideration of the precursors. Groundwater level monitoring data, as well as hydrogeochemical information and microbial communities, may contribute to a more detailed understanding of groundwater flow and chemical reactions in bedrock caused by earthquakes. Therefore, the establishment of a national groundwater monitoring network for seismic monitoring and prediction is required.

A Review of In-Situ Characterization and Quality Control of EDZ During Construction of Final Disposal Facility for Spent Nuclear Fuel (사용후핵연료 최종처분장 건설과정에서의 굴착손상영역(EDZ)의 현장평가 방법 및 시공품질관리 체계에 관한 사례검토)

  • Kim, Hyung-Mok;Nam, Myung Jin;Park, Eui-Seob
    • Tunnel and Underground Space
    • /
    • v.32 no.2
    • /
    • pp.107-119
    • /
    • 2022
  • Excavation-Disturbed Zone (EDZ) is an important design factor in constructing final disposal facilities for spent nuclear fuel, since EDZ affects mechanical stability including a spacing between disposal holes, and the hydraulic properties within EDZ plays a significant role in estimating in-flow rate of groundwater as well as a subsequent corrosion rate of a canister. Thus, it is highly required to characterize in-situ EDZ with precision and control the EDZ occurrence while excavating disposal facilities and constructing relevant underground research facilities. In this report, we not only reviewed EDZ-related researches carried out in the ONKALO facility of Finland but also examined appropriate methods for field inspection and quality control of EDZ occurrence. From the review, GPR can be the most efficient method for in-situ characterization of EDZ since it does not demand drilling a borehole that may disturb a surrounding environment of caverns. And the EDZ occurrence was dominant at a cavern floor and it ranged from 0 to 70 cm. These can provide useful information in developing necessary EDZ-related regulations for domestic disposal facilities.

Analysis of Research Trends in Tax Compliance using Topic Modeling (토픽모델링을 활용한 조세순응 연구 동향 분석)

  • Kang, Min-Jo;Baek, Pyoung-Gu
    • The Journal of the Korea Contents Association
    • /
    • v.22 no.1
    • /
    • pp.99-115
    • /
    • 2022
  • In this study, domestic academic journal papers on tax compliance, tax consciousness, and faithful tax payment (hereinafter referred to as "tax compliance") were comprehensively analyzed from an interdisciplinary perspective as a representative research topic in the field of tax science. To achieve the research purpose, topic modeling technique was applied as part of text mining. In the flow of data collection-keyword preprocessing-topic model analysis, potential research topics were presented from tax compliance related keywords registered by the researcher in a total of 347 papers. The results of this study can be summarized as follows. First, in the keyword analysis, keywords such as tax investigation, tax avoidance, and honest tax reporting system were included in the top 5 keywords based on simple term-frequency, and in the TF-IDF value considering the relative importance of keywords, they were also included in the top 5 keywords. On the other hand, the keyword, tax evasion, was included in the top keyword based on the TF-IDF value, whereas it was not highlighted in the simple term-frequency. Second, eight potential research topics were derived through topic modeling. The topics covered are (1) tax fairness and suppression of tax offenses, (2) the ideology of the tax law and the validity of tax policies, (3) the principle of substance over form and guarantee of tax receivables (4) tax compliance costs and tax administration services, (5) the tax returns self- assessment system and tax experts, (6) tax climate and strategic tax behavior, (7) multifaceted tax behavior and differential compliance intentions, (8) tax information system and tax resource management. The research comprehensively looked at the various perspectives on the tax compliance from an interdisciplinary perspective, thereby comprehensively grasping past research trends on tax compliance and suggesting the direction of future research.