• Title/Summary/Keyword: Field observations

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Calculations of the Single-Scattering Properties of Non-Spherical Ice Crystals: Toward Physically Consistent Cloud Microphysics and Radiation (비구형 빙정의 단일산란 특성 계산: 물리적으로 일관된 구름 미세물리와 복사를 향하여)

  • Um, Junshik;Jang, Seonghyeon;Kim, Jeonggyu;Park, Sungmin;Jung, Heejung;Han, Suji;Lee, Yunseo
    • Atmosphere
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    • v.31 no.1
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    • pp.113-141
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    • 2021
  • The impacts of ice clouds on the energy budget of the Earth and their representation in climate models have been identified as important and unsolved problems. Ice clouds consist almost exclusively of non-spherical ice crystals with various shapes and sizes. To determine the influences of ice clouds on solar and infrared radiation as required for remote sensing retrievals and numerical models, knowledge of scattering and microphysical properties of ice crystals is required. A conventional method for representing the radiative properties of ice clouds in satellite retrieval algorithms and numerical models is to combine measured microphysical properties of ice crystals from field campaigns and pre-calculated single-scattering libraries of different shapes and sizes of ice crystals, which depend heavily on microphysical and scattering properties of ice crystals. However, large discrepancies between theoretical calculations and observations of the radiative properties of ice clouds have been reported. Electron microscopy images of ice crystals grown in laboratories and captured by balloons show varying degrees of complex morphologies in sub-micron (e.g., surface roughness) and super-micron (e.g., inhomogeneous internal and external structures) scales that may cause these discrepancies. In this study, the current idealized models representing morphologies of ice crystals and the corresponding numerical methods (e.g., geometric optics, discrete dipole approximation, T-matrix, etc.) to calculate the single-scattering properties of ice crystals are reviewed. Current problems and difficulties in the calculations of the single-scattering properties of atmospheric ice crystals are addressed in terms of cloud microphysics. Future directions to develop physically consistent ice-crystal models are also discussed.

TLC, HPTLC FINGERPRINTING AND ACUTE ORAL TOXICITY EVALUATION OF HABB-E-AZARAQI: A NUX-VOMICA-BASED TRADITIONAL UNANI FORMULATION

  • Ara, Shabnam Anjum;Viquar, Uzma;Zakir, Mohammed;Husain, Gulam Mohammed;Naikodi, Mohammed Abdul Rasheed;Urooj, Mohd;Kazmi, Munawwar Husain
    • CELLMED
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    • v.11 no.3
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    • pp.13.1-13.9
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    • 2021
  • Background and Objective: Nux-vomica based traditional Unani formulation, Habb-e-Azaraqi (HAZ) is an important drug used by Unani physicians since several decades. It possesses Muqawwi-i-A'sab (nervine tonic), Muharrik-i-A'sab (nervine stimulant) properties and is an effective treatment option for diseases like Laqwa (facial palsy), Falij (paralysis), Niqris (gout) and Waja'al-Mafasil (arthritis) etc. The aim of the study is to access and provide information of HAZ for its TLC, HPTLC Fingerprinting defining its clear qualitative perspective and acute oral toxicity evaluation for its safety assessment which was not done earlier, thus contributing in the field of research. Materials and Methods: The chief ingredient, nux-vomica was detoxified as per method mentioned in Unani Pharmacopeia before its use in formulation. TLC and HPTLC was developed under four detection system i.e., UV 366nm, UV 254nm, exposure to iodine vapours and after derivatization with anisaldehyde sulphuric acid. Acute toxicity studies were performed as per OECD Guidelines 425 at a limit dose of 2000 mg/kg. Observations were done for signs of toxicity, body weight, and feed consumption at regular intervals followed by haematological and biochemistry evaluation. Results: The generated data proved the authenticity and established the TLC and HPTLC profile of the formulation. Acute toxicity revealed no significant differences in HAZ-treated animals with respect to body weight gain, feed consumption, haematology, clinical biochemistry evaluation. No significant gross pathological observation was noticed in necropsy. Conclusion: Data of the present study is substantial and scientific proof of HAZ in terms of standardization and toxicity study that can be utilize in future research activities.

A Study on Factors Affecting the Reuse of Research Data by Academic Researchers in the Social Sciences (사회과학분야 학술 연구자의 연구데이터 재이용 영향요인 연구)

  • Bak, Ji Won;Chang, Woo Kwon
    • Journal of the Korean Society for information Management
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    • v.38 no.4
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    • pp.199-230
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    • 2021
  • This study is to present an analysis and activation plan for the effect of reuse of research data through investigation of researchers and reuse data on reuse of research data. To this end, 178 copies were analyzed based on the distribution and collection of surveys targeting academic researchers in the field of social science in Korea who have experience in calculating new research results by reusing research data. As a result, 1) Most researchers acquire reuse data through systems such as data repositories, data management systems, and research data DBs, and mainly reuse analysis data produced through experiments and observations. In addition, despite being a researcher who successfully reused research data, the awareness of research data sharing was low and did not share it in the face of various problems. 2) The reliability and validity of 10 factors derived through literature review and factor analysis (academic usefulness, research efficiency, researcher concerns, data vulnerability, direct effort, indirect effort, suitability for reuse, data completeness, data usefulness, and social conditions) were verified. 3) As a result of correlation analysis, research efficiency, social conditions showed a quantitative correlation with research data reuse intention, researcher concerns, data vulnerability, and direct effort showed a negative correlation with research data reuse intention. As a result of regression analysis, all of these factors had a significant effect on the intention to reuse research data, and in the order of research efficiency, social conditions, direct efforts, researchers' concerns, and data vulnerability. Based on this, a plan to revitalize the reuse of research data was proposed.

SNIPE Mission for Space Weather Research (우주날씨 관측을 위한 큐브위성 도요샛 임무)

  • Lee, Jaejin;Soh, Jongdae;Park, Jaehung;Yang, Tae-Yong;Song, Ho Sub;Hwang, Junga;Kwak, Young-Sil;Park, Won-Kee
    • Journal of Space Technology and Applications
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    • v.2 no.2
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    • pp.104-120
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    • 2022
  • The Small Scale magNetospheric and Ionospheric Plasma Experiment (SNIPE)'s scientific goal is to observe spatial and temporal variations of the micro-scale plasma structures on the topside ionosphere. The four 6U CubeSats (~10 kg) will be launched into a polar orbit at ~500 km. The distances of each satellite will be controlled from 10 km to more than ~1,000 km by the formation flying algorithm. The SNIPE mission is equipped with identical scientific instruments, Solid-State Telescopes(SST), Magnetometers(Mag), and Langmuir Probes(LP). All the payloads have a high temporal resolution (sampling rates of about 10 Hz). Iridium communication modules provide an opportunity to upload emergency commands to change operational modes when geomagnetic storms occur. SNIPE's observations of the dimensions, occurrence rates, amplitudes, and spatiotemporal evolution of polar cap patches, field-aligned currents (FAC), radiation belt microbursts, and equatorial and mid-latitude plasma blobs and bubbles will determine their significance to the solar wind-magnetosphere-ionosphere interaction and quantify their impact on space weather. The formation flying CubeSat constellation, the SNIPE mission, will be launched by Soyuz-2 at Baikonur Cosmodrome in 2023.

Plant Species Richness in Korea Utilizing Integrated Biological Survey Data (생물기초조사 통합자료를 활용한 우리나라 식물종 풍부도 분석)

  • Seungbum Hong;Jieun Oh;Jaegyu Cha;Kyungeun Lee
    • Korean Journal of Ecology and Environment
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    • v.56 no.4
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    • pp.363-374
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    • 2023
  • The limitation in deriving the species richness representing the entire country of South Korea lies in its relatively short history of species field observations and the scattered observation data, which has been collected by various organizations in different fields. In this study, a comprehensive compilation of the observation data for plants held by agencies under the Ministry of Environment was conducted, enabling the construction of a time series dataset spanning over 100 years. The data integration was carried out using minimal criteria such as species name, observed location, and time (year) followed by data verification and correction processes. Based on the integrated plant species data, the comprehensive collection of plant species in South Korea has occurred predominantly since 2000, and the number of plant species explored through these surveys appears to be converging recently. The collection of species survey data necessary for deriving national-level biodiversity information has recently begun to meet the necessary conditions. Applying the Chao 2 method, the species richness of indigenous plants estimated at 3,182.6 for the 70-year period since 1951. A minimum cumulative period of 7 years is required for this estimation. This plant species richness from this study can be a baseline to study future changes in species richness in South Korea. Moreover, the integrated data with the estimation method for species richness used in this study appears to be applicable to derive regional biodiversity indices such as for local government units as well.

Comparison of the Vertical Data between Eulerian and Lagrangian Method (오일러와 라그랑주 관측방식의 연직 자료 비교)

  • Hyeok-Jin Bae;Byung Hyuk Kwon;Sang Jin Kim;Kyung-Hun Lee;Geon-Myeong Lee;Yu-Jin Kim;Ji-Woo Seo;Yu-Jung Koo
    • The Journal of the Korea institute of electronic communication sciences
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    • v.18 no.6
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    • pp.1009-1014
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    • 2023
  • Comprehensive observations of the Euler method and the Lagrangian method were performed in order to obtain high-resolution observation data in space and time for the complex environment of new city. The two radiosondes, which measure meteorological parameters using Lagrangian methods, produced air pressure, wind speed and wind direction. They were generally consistent with each other even if the observation points or times were different. The temperature measured by the sensor exposed to the air during the day was relatively high as the altitude increased due to the influence of solar radiation. The temporal difference in wind direction and speed was found in the comparison of Euler's wind profiler data with radiosonde data. When the wind field is horizontally in homogeneous, this result implies the need to consider the advection component to compare the data of the two observation methods. In this study, a method of using observation data at different times for each altitude section depending on the observation period of the Euler method is proposed to effectively compare the data of the two observation methods.

Study of Confidence Ranges for Field Phase Difference Measurement Data Collected using Geophones (지오폰을 활용한 현장 위상각차 계측 데이터 신뢰 구간에 관한 기초 연구)

  • Kim, Gunwoong
    • Journal of the Korean Geotechnical Society
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    • v.40 no.3
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    • pp.41-54
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    • 2024
  • Regular monitoring plays a crucial role in ensuring the safety of geotechnical structures. Currently, nondestructive methods are employed to monitor such structures to minimize the impact, e.g., sensor-based accelerometers, displacement meters, image-based lasers, and drone imaging. These technologies can observe surface changes; however, they frequently suffer difficulties in terms of identifying changes in internal properties. To monitor changes in internal properties, in situ geotechnical investigations can be employed. A nondestructive test that can be used for this purpose is the spectral analysis of surface wave (SASW) test using geophones. The SASW test is a nondestructive method; however, due to the time required for data interpretation and the difficulty in analyzing the data, it is challenging to use the SASW test for monitoring applications that require frequent observations. However, it is possible to apply the first-step analysis, which yields the dispersion curve, for monitoring rather than the complete SASW analysis, which yields the shear wave velocity. Thus, this paper presents a fundamental study on the phase difference that derives the dispersion curve to utilize the SASW test for monitoring. The reliability of each phase difference interval is examined to determine the boundary to the subjected monitor. The study used phase difference data obtained using a geophone from a single-layered, homogeneous ground site to evaluate reliable boundaries. The findings of this study are expected to improve the utility of monitoring by identifying the ideal boundary for phase difference data.

Occurrence and Variation of Oxygen Deficient Water Mass in the Namdae Stream Estuary, Yangyang, Korea (양양 남대천 하구의 빈산소 수괴 출현과 변동)

  • Kwon, Kee-Young;Lee, Yong-Hwa;Shim, Jeong-Min;Lee, Pil-Yong
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.15 no.3
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    • pp.115-123
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    • 2010
  • The occurrence and variation of oxygen deficient water mass (ODW) in Namdae stream estuary, Yangyang were studied. Field observations for water properties and sediment environments were conducted at 5 stations of the estuary from April 2008 to November 2008. The coastal sandbar is developed at the estuary mouth, and there is a pool between the estuary mouth and about 2.3 km upstream of the estuary. The pool is relatively deep and narrow compared to riverbed of the estuary. The ODW was observed continuously in the pool from May to October. The ODW extends vertically up to 2 m depth in August, and maximum length of the ODW were about 2.3 km. Mean concentration of ignition loss (IL) and acid volatile sulfide (AVS) of sediment was 7.5~9.0%, $0.282{\sim}1.106\;mg/g{\cdot}dry$ wt, respectively. Ammonium concentration in the bottom layer during formation period of the halocline and the ODW was 4~23 times higher than that of surface layer. ODW was initiated by the introduction of seawater into bottom of the estuary pool to make a strong halocline, and then decomposition of organic matter within sediment accelerated the formation of the ODW.

A Study on Educational Program and Spatial Characteristics of Mixed-use School Facilities C - Focusing on 'Eumteo' of Hwaseong-si, Gyeonggi-do - (학교시설 복합화의 교육프로그램과 공간특성에 관한 연구 - 경기도 화성시 복합화 이음터를 중심으로 -)

  • Seo, Yu-Jung;Shim, Eun-Ju
    • The Journal of Sustainable Design and Educational Environment Research
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    • v.23 no.1
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    • pp.1-11
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    • 2024
  • Complex school facilities are being considered to meet increased public demands for culture and welfare in Korea, given the decreasing population. In this context, Gyeongi-do Hwaseong City's E-umteo is recognized as a relatively well-operated school complex. Therefore, this study considered seven E-umteo branches as case studies to examine the operations of educational programs and understand the techniques employed in the spatial configuration of E-umteo. To this end, field observations and interviews with facility operators were conducted. The case analysis results revealed that educational programs could be classified into three types: learning sharing , community communication, and lifelong learning. Furthermore, the learning sharing type was classified into education and physical education while the community communication type was classified into the community and convenience types. Meanwhile, lifelong learning was identified as the most actively used type by differentiating specialized programs. With regard to the spatial composition between the school and the "pitcher," only the connection and independent types were observed, and no integral type was discovered. Therefore, integrated future studies are mandated.

Seasonal Sedimentary Characteristics and Depositional Environments after the Construction of seawall on the Iwon Macrotidal Flat (방조제 건설 후 이원 대조차 조간대의 계절별 퇴적학적 특성 및 퇴적환경)

  • Kum, Byung-Cheol;Park, Eun-Young;Lee, Hi-Il;Oh, Jae-Kyung;Shin, Dong-Hyeok
    • Journal of the Korean earth science society
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    • v.25 no.7
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    • pp.615-628
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    • 2004
  • In order to elucidate seasonal sedimentary characteristics and depositional environment after construction of seawall on macrotidal flat, a seasonal observations of surface sediments (total 450) and sedimentation rates on 4 transects have been investigated for 2 years. The eastern area of Iwon tidal flat, has been changed from semi-closed coast to open coast by construction of seawall, shows general seasonal changes similar to characteristics of open coast type, which represented both fining and bad sorted distribution due to deposition of fine sediments under low energy condition in the summer, and relatively coarser and better sorted distribution because of erosion of fine sediments in the winter. In considering angles of transects, distribution patterns of surface sediments, the northern and southern parts of eastern tidal flat are dominantly influenced by wave and tidal effects, respectively. As time goes by, the eastern tidal flat shows coarsening-trend of surface sediments caused by direct effect of tidal current, were and typhoon. Meanwhile the western area of seawall, which has been re-formed by construction seawall, is sheltered from northwesterly seasonal wind. The seasonal change pattern of western area of seawall is slightly different from that of eastern tidal flat. Mean grain size and sorting of surface sediments during spring is finer and worse than those during summer. This seasonal change pattern maybe influenced by topographic effects caused from the construction of seawall. In consideration of all result, the transport of fine sediments in the study area, which is supplied to limited sediments, shows clockwise circulation pattern that fine sediments are transported from the eastern tidal flat to the western area of seawall because of blocking of seawall in the winter and are transported reversed direction the summer. As a result, many changes have been observed in the study area after construction of seawall; however, this change is still in progress and is expected to need continuous monitoring.