• Title/Summary/Keyword: Mass Science

검색결과 9,452건 처리시간 0.034초

Weak-lensing Mass Reconstruction of Galaxy Clusters with Convolutional Neural Network

  • Hong, Sungwook E.;Park, Sangnam;Jee, M. James;Bak, Dongsu;Cha, Sangjun
    • 천문학회보
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    • 제45권1호
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    • pp.49.4-50
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    • 2020
  • We introduce a novel method for reconstructing the projected matter distributions of galaxy clusters with weak-lensing (WL) data based on convolutional neural network (CNN). We control the noise level of the galaxy shear catalog such that it mimics the typical properties of the existing Subaru/Suprime-Cam WL observations of galaxy clusters. We find that our mass reconstruction based on multi-layered CNN with architectures of alternating convolution and trans-convolution filters significantly outperforms the traditional mass reconstruction methods.

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신장(腎臟)mass 감소(減少)가 혈액요소질소(血液尿素窒素)와 혈청(血淸) 크레아티닌 농도(濃度)에 미치는 영향 (Effects of Reductions in Renal Mass on Blood Urea Nitrogen and Serum Creatinine Concentrations in dogs)

  • 남치주
    • 대한수의학회지
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    • 제22권1호
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    • pp.81-84
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    • 1982
  • Renal dysfunction was experimentally induced with reductions in renal mass in dogs and then the remaining kidney function was estimated by blood urea nitrogen and serum creatinine concentrations. During experimental period, blood urea nitrogen and serum creatinine concentrations showed no variance in dogs with 50% reductions in renal mass, but these values were remarkably increased in dogs with 75% reductions in renal mass. It was considered that 75% reductions in renal mass was applicable as experimental models for renal dysfunction.

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Aerosol Mass Spectrometer (AMS)-Based Real-Time Physicochemical Characterization of Atmospheric Aerosols

  • Kim, Donghwi
    • Mass Spectrometry Letters
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    • 제13권2호
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    • pp.27-34
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    • 2022
  • Atmospheric aerosols have become a major environmental concern because of their adverse effects on human health, air quality, and climate change. Over the last few decades, several mass spectrometry (MS)-based techniques have been developed and applied in the field of atmospheric aerosol research. Particularly, real-time measurement of ambient aerosols using an aerosol mass spectrometer (AMS) has become one of the most powerful tools for aerosol chemistry. This review provides a brief description of AMS and its applications for understanding the physicochemical properties of atmospheric aerosols, as well as its sources and evolution processes.

유가금속(有價金屬) 회수(回收)를 위한 PCB 스크랩의 건식처리기술(乾式處理技術) (Pyro-metallurgical Treatment of used OA Parts for the Recovery of Valuable Metals)

  • 신동엽;이상동;정현부;유병돈;한정환;정진기
    • 자원리싸이클링
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    • 제17권2호
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    • pp.46-54
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    • 2008
  • 폐 컴퓨터나 OA기기 중 PCB (Printed Circuit Board)에는 귀금속을 포함한 많은 양의 금속성분이 함유되어 있으며, 본 연구에서는 이들을 분리회수하기 위한 건식처리 기술을 검토하였다. 폐 컴퓨터로부터 얻은 PCB 스크랩을 산화처리한 시료에 대해 정량분석을 실시하고, 함유된 산화물 종류에 대하여 적합한 슬래그계를 선정하여 유가금속을 분리회수하기 위한 산화물 성분의 슬래그화를 시도하였다. 용융작업을 위해 슈퍼칸탈 회전로를 사용하였으며, 이때 도가니 회전이 금속의 회수율에 미치는 영향을 조사하였다.

노인의 운동참여, 근육량, 근력 및 인지기능과의 관련성 (Relationship between Exercising Activity, Muscle Mass, Muscular Strength and Cognitive Function in the Elderly)

  • 최재원;유하나;이현우;강성구;정혜연
    • 한국융합학회논문지
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    • 제9권5호
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    • pp.219-229
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    • 2018
  • 본 연구는 서울 경기에 거주하며 운동에 참여하는 65세 이상 274명을 대상으로 노인의 운동참여, 근육량, 근력과 인지기능의 정량적 지표를 토대로 이들 간의 관계성을 규명하고자 하였다. 자료수집은 연구대상자의 운동참여(참여 빈도, 참여 시간), 근육량, 근력(상지근력, 하지근력), 인지기능(한국판 간이정신상태검사, 숫자 바로 읽기, 숫자 거꾸로 읽기)을 측정하여 자료를 수집하였다. 일련의 타당성 있는 연구절차를 통하여 도출된 결론은 다음과 같다. 첫째, 노인의 운동참여, 근육량, 근력, 인지기능 간에는 통계적 유의한 상관관계가 나타났다. 둘째, 노인의 운동참여는 근육량, 근력, 인지기능에 정적(+) 영향력을 나타내었다. 셋째, 노인의 근육량은 근력, 인지기능에 통계적 유의한 정적(+) 영향력을 나타내었다. 넷째, 노인의 근력은 인지기능에 정적(+) 영향력을 나타내었다.

Effect of Stewing Time on the Small Molecular Metabolites, Free Fatty Acids, and Volatile Flavor Compounds in Chicken Broth

  • Rong Jia;Yucai Yang;Guozhou Liao;Yuan Yang;Dahai Gu;Guiying Wang
    • 한국축산식품학회지
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    • 제44권3호
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    • pp.651-661
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    • 2024
  • Chicken broth has a taste of umami, and the stewing time has an important effect on the quality of chicken broth, but there are fewer studies on the control of the stewing time. Based on this, the study was conducted to analyze the effects of different stewing times on the sensory, small molecular metabolites, free fatty acids, and volatile flavor compounds contents in chicken broths by liquid chromatography-quadrupole/time-of-flight mass spectrometry, gas chromatography-mass spectrometry, headspace solid-phase microextraction, and gas chromatography-mass spectrometry. Eighty-nine small molecular metabolites, 15 free fatty acids, and 86 volatile flavor compounds were detected. Palmitic and stearic acids were the more abundant fatty acids, and aldehydes were the main volatile flavor compounds. The study found that chicken broth had the best sensory evaluation, the highest content of taste components, and the richest content of volatile flavor components when the stewing time was 2.5 h. This study investigated the effect of stewing time on the quality of chicken broth to provide scientific and theoretical guidance for developing and utilizing local chicken.

잔류기체 분석기 교정장치 개발 (Development of a Residual Gas Analyzer Calibration System)

  • 홍승수;임인태;김진태
    • 한국진공학회지
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    • 제16권2호
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    • pp.91-98
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    • 2007
  • 한국표준과학연구원 진공기술센터에서 잔류기체분석기 교정장치를 개발하였으며, 이 장치를 이용하여 서로 다른 구조를 가진 두개의 사중극 질량분석기 (quadrupole mass spectrometer)의 질소, 아르곤, 헬륨에 대한 기체감도를 측정하였다. 그 결과 기체감도는 QMS 구조와 상관없이 기체의 질량이 클수록 높게 나타났고 압력에 따라서도 다른 특성을 보였으므로 정확한 사용을 위해서는 기체감도를 꼭 보정해야 함을 알 수 있었다.

Current technology and industrialization status of cell-cultivated meat

  • Seung Yun Lee;Da Young Lee;Seung Hyeon Yun;Juhyun Lee;Ermie Jr Mariano;Jinmo Park;Yeongwoo Choi;Dahee Han;Jin Soo Kim;Sun Jin Hur
    • Journal of Animal Science and Technology
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    • 제66권1호
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    • pp.1-30
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    • 2024
  • Interest and investment in cultivated meat are increasing because of the realization that it can effectively supply sufficient food resources and reduce the use of livestock. Nevertheless, accurate information on the specific technologies used for cultivated meat production and the characteristics of cultivated meat is lacking. Authorization for the use of cultivated meat is already underway in the United States, Singapore, and Israel, and other major countries are also expected to approve cultivated meat as food once the details of the intricate process of producing cultivated meat, which encompasses stages such as cell proliferation, differentiation, maturation, and assembly, is thoroughly established. The development and standardization of mass production processes and safety evaluations must precede the industrialization and use of cultivated meat as food. However, the technology for the industrialization of cultivated meat is still in its nascent stage, and the mass production process has not yet been established. The mass production process of cultivated meat may not be easy to disclose because it is related to the interests of several companies or research teams. However, the overall research flow shows that equipment development for mass production and cell acquisition, proliferation, and differentiation, as well as for three-dimensional production supports and bioreactors have not yet been completed. Therefore, additional research on the mass production process and safety of cultivated meat is essential. The consumer's trust in the cultivated meat products and production technologies recently disclosed by some companies should also be analyzed and considered for guiding future developments in this industry. Furthermore, close monitoring by academia and the government will be necessary to identify fraud in the cultivated meat industry.

Experimental study of strength characteristics of reinforced broken rock mass

  • Yanxu Guo;Qingsong Zhang;Hongbo Wang;Rentai Liu;Xin Chen;Wenxin Li;Lihai Zhang
    • Geomechanics and Engineering
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    • 재33권6호
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    • pp.553-565
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    • 2023
  • As the structure of broken rock mass is complex, with obvious discontinuity and anisotropy, it is generally necessary to reinforce broken rock mass using grouting in underground construction. The purpose of this study is to experimentally investigate the mechanical properties of broken rock mass after grouting reinforcement with consideration of the characteristics of broken rock mass (i.e., degree of fragmentation and shape) and a range of reinforcement methods such as relative strength ratio between the broken rock mass and cement-based grout stone body (λ), and volumetric block proportion (VBP) representing the volumetric ratio of broken rock mass and the overall cement grout-broken rock mass mixture after the reinforcement. The experimental results show that the strength and deformation of the reinforced broken rock mass is largely determined by relative strength ratio (λ) and VBP. In addition, the enhancement in compressive strength by grouting is more obvious for broken rock mass with spherical shape under a relatively high strength ratio (e.g., λ=2.0), whereas the shape of rock mass has little influence when the strength ratio is low (e.g., λ=0.1). Importantly, the results indicate that columnar splitting failure and inclined shear failure are two typical failure modes of broken rock mass with grouting reinforcement.