• Title/Summary/Keyword: Time Of Flight

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A Study of the Characteristics of Highly Spatially Resolved CW-laser-based Aerosol Lidar (고공간분해능 연속 광원을 이용한 미세먼지 라이다의 신호 특성에 관한 연구)

  • Sim, Juhyeon;Kim, Taekeong;Ju, Sohee;Noh, Youngmin;Kim, Dukhyeon
    • Korean Journal of Optics and Photonics
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    • v.33 no.1
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    • pp.1-10
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    • 2022
  • In this study we introduce a new method for high-spatial-resolution continuous wave (CW) aerosol lidar that has a high spatial resolution in the near field and a low spatial resolution at long distances. A normal lidar system uses a nanosecond-pulse laser and measures the round-trip TOF between the aerosol and laser to obtain range resolution. In this study, however, we propose a new type of spatially resolving aerosol lidar that uses laser-scattering images. Using a laser-light-scattering image, we have calculated the distance of each scattering aerosol image for a given pixel, and recovered the short-range aerosol extinction. For this purpose, we have calculated the distance image and the contribution range of the aerosol to the given one-pixel image, and finally we have calculated the extinction coefficients of the aerosol with range-resolved information. In the case of traditional aerosol lidar, we can only obtain the aerosol extinction coefficients above 400 m. Using our suggested method, it was possible to extend the range of the extinction coefficient lower then several tens of meters. Finally, we can remove the unknown short-range region of pulsed aerosol lidar using our method.

A Study on the Effective Utilization of Public Service Drones - Focused on Search and Rescue Drones - (공공임무용 드론의 효과적 활용방안에 관한 연구 - 실종자 수색용 드론을 중심으로 -)

  • Kang, Wook
    • Korean Security Journal
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    • no.62
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    • pp.65-86
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    • 2020
  • Drones, which were originally developed for military purpose, have expanded rapidly not only in hobbies, leisure, but also in broadcasting, filming, and public sectors, and search and rescue drones have been used to find four Korean teachers who went to Nepal for volunteer work but went missing in the avalanche. The government is encouraging the use of drones in the public sector as a policy to foster the drone industry, and the market is expected to expand in the future. This study presents improvement measures and specific directions for use of drones by public agencies at a time when the use of drones is expanding in the public sector. To that end, this research reviewed the interviews of relevant experts, analysis of drone operation regulations by public agencies, and the cases of operation of drones for searching missing persons by police. First of all, it will have to secure skilled personnel before the introduction of the drones and then determine the specifications of the drones through sufficient review, and then be put into the mission after careful examination of the drones. Next, it is necessary to draw up a base rule for drone operation and draw up a manual accordingly. Finally, drone flight has the risk of a crash, and it is essential to secure dedicated personnel for drone operation, especially since drones in the public sector are specialized in large scale compared to hobby drones to achieve their purpose. This research only conducted a detailed analysis of the National Police Agency's drones for searching for missing persons, and there are limitations to the number of people interviewed. Subsequent studies will require analysis of various public institutions, and in addition to interviews, surveys will require analysis of various data and statistics.

A Study on the Modernization of the Rome Convention and its Issues - Focusing on the recent ICAO Legal Committee's Discussion (로마조약의 현대화와 쟁점에 관한 고찰 - 최근 ICAO법률위원회의 논의를 중심으로 -)

  • Kim, Jong-Bok;Maeng, Sung-Kyu
    • The Korean Journal of Air & Space Law and Policy
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    • v.23 no.1
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    • pp.33-54
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    • 2008
  • The damage to the third parties caused by aircraft in flight shall be fully compensated to the extent that the damage didn't occur unless the damage is caused by innocent victims. However, related international Conventions limit operator's liability of compensation to certain levels, which is one of the main reasons that such international Conventions have not been ratified by many aviation leading States. However, international community has agreed, since 9/11, that the accidents caused by terrorists and the protection of the third parties need to be addressed more actively. And the amendment of the related Rome Conventions has been drafted under the ICAO leadership by the special committee that was organized to modernize the related international Conventions. This study addresses the issues related to the draft Conventions, the draft Convention for Damage caused by Aircraft to Third Parties, in case of Unlawful Interference and the draft Convention on compensation for Damage caused by Aircraft to Third Parties. It is expected that it takes considerable time to reach an agreement on all the issues from appropriate apportionment of liability between the government and operator to the details regarding the management of Supplementary Compensation Mechanism. Under the circumstances where the needs for the air transportation as well as threats of terrorism increase, the new international Convention should be prepared taking into consideration the balance between the protection of the innocent third parties and that of air transport industry including air carriers. Along with this, the Republic of Korea should actively participate in the process of amendment to the related international Conventions to protect the life and property of the people from anticipated damages.

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Design Optimization of Multi-element Airfoil Shapes to Minimize Ice Accretion (결빙 증식 최소화를 위한 다중 익형 형상 최적설계)

  • Kang, Min-Je;Lee, Hyeokjin;Jo, Hyeonseung;Myong, Rho-Shin;Lee, Hakjin
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.50 no.7
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    • pp.445-454
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    • 2022
  • Ice accretion on the aircraft components, such as wings, fuselage, and empennage, can occur when the aircraft encounters a cloud zone with high humidity and low temperature. The prevention of ice accretion is important because it causes a decrease in the aerodynamic performance and flight stability, thus leading to fatal safety problems. In this study, a shape design optimization of a multi-element airfoil is performed to minimize the amount of ice accretion on the high-lift device including leading-edge slat, main element, and trailing-edge flap. The design optimization framework proposed in this paper consists of four major parts: air flow, droplet impingement and ice accretion simulations and gradient-free optimization algorithm. Reynolds-averaged Navier-Stokes (RANS) simulation is used to predict the aerodynamic performance and flow field around the multi-element airfoil at the angle of attack 8°. Droplet impingement and ice accretion simulations are conducted using the multi-physics computational analysis tool. The objective function is to minimize the total mass of ice accretion and the design variables are the deflection angle, gap, and overhang of the flap and slat. Kriging surrogate model is used to construct the response surface, providing rapid approximations of time-consuming function evaluation, and genetic algorithm is employed to find the optimal solution. As a result of optimization, the total mass of ice accretion on the optimized multielement airfoil is reduced by about 8% compared to the baseline configuration.

Monoclonal antibody production for CP4 EPSPS detection assays (CP4 EPSPS 검출을 위한 단클론 항체 생산)

  • A-Mi Yoon;Il Ryong Kim;Wonkyun Choi
    • Korean Journal of Environmental Biology
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    • v.39 no.4
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    • pp.445-451
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    • 2021
  • In this study, we described the production of an antibody to living modified organisms (LMOs) containing the gene encoding for 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) from Agrobacterium tumefaciens strain CP4 EPSPS provides resistance to the herbicide glyphosate (N- (phosphonomethyl) glycine). These LMOs were approved and have recently been used in the feed, food production, and processing industries in South Korea. Highly efficient monoclonal antibody (mAb) production is crucial for developing assays that enable the proper detection and quantification of the CP4 EPSPS protein in LMOs. This study describes the purification and characterization of recombinant CP4 EPSPS protein in E. coli BL21 (DE3) based on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and matrixassisted laser desorption/ionization time-of-flight mass spectrometry. The production of mAbs was undertaken based on the standard operating procedure of Abclon, Inc.(South Korea), and the purity of the mAbs was assessed using SDS-PAGE. The following five mAb clones were produced: 2F2, 4B9, 6C11, 10A9, and 10G9. To verify the efficiency and specificity of the five developed mAbs, we performed Western blotting analysis using the LM (living modified) cotton crude extracts. All mAbs could detect the CP4 EPSPS protein in the LM cotton traits MON1445 and MON88913 with high specificity, but not in any other LM cottons or non-LM cottons. These data indicate that these five mAbs to CP4 EPSPS could be successfully used for the further development of antibody-based detection methods to target CP4 EPSPS protein in LMOs.

Proteomics of Protein Expression Profiling in Tissues with Different Radiosensitivity (Proteomics를 이용한 마우스 조직에서의 방사선 감수성 조절 단백질의 탐색)

  • An, Jeung-Hee;Kim, Ji-Young;Seong, Jin-Sil
    • Radiation Oncology Journal
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    • v.22 no.4
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    • pp.298-306
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    • 2004
  • Purpose: The purpose of this study was to identify Radiosensitivity of proteins in tissues with different radiosensitivity. Materials and Methods: C3H/HeJ mice were exposed to 10 Gy. The mice were sacrifiud 8 hrs after radiation. Their spleen and liver tissues were collected and analyzed histologicaly for apoptosis. The expressions of radiosusceptibillty protein were analyzed by 2-dimensional electrophoresis and matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Resilts: The Peak of apoptosis levels were $35.3{\pm}1.7{\%}$ in spleen and $0.6{\pm}0.2{\%}$ in liver at 8 hrs after radiation. Liver, radioresistant tissues, showed that the levels of ROS metabolism related to proteins such as cytochromm c, glutathione S transferase, NADH dehydrogenase, riken cDNA and peroxiredoxin Vl increased after radiation. The expression of cytochrome c increased significantly in spleen and liver tissues after radiation. In spleen, radiosensitivity tissue, the identified proteins showed a significantly quantitative alteration following radiation. It was categorized as signal transduction, apoptosis, cytokine, Ca signal related protein, stress-related protein, cytoskeletal regulation, ROS metabolism, and others. Conclusion: Differences of radiation-induced apoptosis by tissues specifted were coupled with the induction of related radiosensitivity and radioresistant proteins. The result suggests that apoptosis relate protein and redox proteins play important roles in this radiosusceptibility.

Characteristics of Coagulase-negative Staphylococci Isolates from Dental Clinic Environments in Busan, Korea (부산지역 치과환경에서 분리된 coagulase-negative staphylococci의 특성)

  • Jung, Hye-In;Jung, So Young;Park, Indal;Bae, Il Kwon
    • Journal of Life Science
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    • v.26 no.2
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    • pp.220-225
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    • 2016
  • Coagulase-negative staphylococci (CNS) have recently become the bacteria most frequently found in clinical infections. The aim of this study was to investigate the prevalence, antimicrobial susceptibilities, and molecular characteristics of CNS isolates from dental clinic environments in Busan, Korea. One hundred and fifty-four samples were collected from 10 dental clinics and dental hospitals in Busan from December 2014 to January 2015. Species were identified by matrix-assisted laser desorption/ionization–time-of-flight. Antimicrobial susceptibility was determined by disk diffusion methods. A polymerase chain reaction was performed to detect mecA, mupA gene, and SCCmec types. Of the 154 samples, 10(6.5%) isolates were identified as CNS (5 Staphylococcus epidermidis, 2 Staphylococcus capitis, 2 Staphylococcus, and 1 Staphylococcus haemolyticus). Among the 10 isolates, 6 were resistant to penicillin, 5 were resistant to gentamicin, 3 were resistant to tetracycline, and 2 were resistant to cefoxitin and erythromycin. However, clindamycin, ciprofloxacin, teicoplanin, and trimethoprim-sulfamethoxazole resistant isolates were not present. Genes encoding mecA were detected in 4 (2 S. warneri and 2 S. haemolyticus) isolates, and mupA in 1 (S. epidermidis) isolate. One methicillin-resistant CNS (S. warneri) isolate was determined as being of the SCCmec type I. It is concluded that CNS resistant to various antimicrobial agents was widely distributed in dental clinic environments in Korea.

Comparative Evaluation of UAV NIR Imagery versusin-situ Point Photo in Surveying Urban Tributary Vegetation (도심소하천 식생조사에서 현장사진과 UAV 근적외선 영상의 비교평가)

  • Lee, Jung-Joo;Hwang, Young-Seok;Park, Seong-Il;Um, Jung-Sup
    • Journal of Environmental Impact Assessment
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    • v.27 no.5
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    • pp.475-488
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    • 2018
  • Surveying urban tributary vegetation is based mainly on field sampling at present. The tributary vegetation survey integrating UAV NIR(Unmanned Aerial Vehicle Near Infrared Radiance) imagery and in-situ point photo has received only limited attentions from the field ecologist. The reason for this could be the largely undemonstrated applicability of UAV NIR imagery by the field ecologist as a monitoring tool for urban tributary vegetation. The principal advantage of UAV NIR imagery as a remote sensor is to provide, in a cost-effective manner, information required for a very narrow swath target such as urban tributary (10m width or so), utilizing very low altitude flight, real-time geo-referencing and stereo imaging. An exhaustive and realistic comparison of the two techniques was conducted, based on operational customer requirement of urban tributary vegetation survey: synoptic information, ground detail and quantitative data collection. UAV NIR imagery made it possible to identify area-wide patterns of the major plant communities subject to many different influences (e.g. artificial land use pattern), which cannot be acquired by traditional field sampling. Although field survey has already gained worldwide recognition by plant ecologists as a typical method of urban tributary vegetation monitoring, this approach did not provide a level of information that is either scientifically reliable or economically feasible in terms of urban tributary vegetation (e.g. remedial field works). It is anticipated that this research output could be used as a valuable reference for area-wide information obtained by UAV NIR imagery in urban tributary vegetation survey.

A Study on Environmental research Trends by Information and Communications Technologies using Text-mining Technology (텍스트 마이닝 기법을 이용한 환경 분야의 ICT 활용 연구 동향 분석)

  • Park, Boyoung;Oh, Kwan-Young;Lee, Jung-Ho;Yoon, Jung-Ho;Lee, Seung Kuk;Lee, Moung-Jin
    • Korean Journal of Remote Sensing
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    • v.33 no.2
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    • pp.189-199
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    • 2017
  • Thisstudy quantitatively analyzed the research trendsin the use ofICT ofthe environmental field using the text mining technique. To that end, the study collected 359 papers published in the past two decades(1996-2015)from the National Digital Science Library (NDSL) using 38 environment-related keywords and 16 ICT-related keywords. It processed the natural languages of the environment and ICT fields in the papers and reorganized the classification system into the unit of corpus. It conducted the text mining analysis techniques of frequency analysis, keyword analysis and the association rule analysis of keywords, based on the above-mentioned keywords of the classification system. As a result, the frequency of the keywords of 'general environment' and 'climate' accounted for 77 % of the total proportion and the keywords of 'public convergence service' and 'industrial convergence service' in the ICT field took up approximately 30 % of the total proportion. According to the time series analysis, the researches using ICT in the environmental field rapidly increased over the past 5 years (2011-2015) and the number of such researches more than doubled compared to the past (1996-2010). Based on the environmental field with generated association rules among the keywords, it was identified that the keyword 'general environment' was using 16 ICT-based technologies and 'climate' was using 14 ICT-based technologies.

Protein Profile in Corpus Luteum during Pregnancy in Korean Native Cows

  • Chung, H.J.;Kim, K.W.;Han, D.W.;Lee, H.C.;Yang, B.C.;Chung, H.K.;Shim, M.R.;Choi, M.S.;Jo, E.B.;Jo, Y.M.;Oh, M.Y.;Jo, S.J.;Hong, S.K.;Park, J.K.;Chang, W.K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.25 no.11
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    • pp.1540-1545
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    • 2012
  • Steroidogenesis requires coordination of the anabolic and catabolic pathways of lipid metabolism, but the profile of proteins associated with progesterone synthesis in cyclic and pregnant corpus luteum (CL) is not well-known in cattle. In Experiment 1, plasma progesterone level was monitored in cyclic cows (n = 5) and pregnant cows (n = 6; until d-90). A significant decline in the plasma progesterone level occurred at d-19 of cyclic cows. Progesterone level in abbatoir-derived luteal tissues was also determined at d 1 to 5, 6 to 13 and 14 to 20 of cyclic cows, and d-60 and -90 of pregnant cows (n = 5 each). Progesterone level in d-60 CL was not different from those in d 6 to 13 CL and d-90 CL, although the difference between d 6 to 13 and d-90 was significant. In Experiment 2, protein expression pattern in CL at d-90 (n = 4) was compared with that in CL of cyclic cows at d 6 to 13 (n = 5). Significant changes in the level of protein expression were detected in 32 protein spots by two-dimensional polyacrylamide gel electrophoresis (2-DE), and 23 of them were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Six proteins were found only in pregnant CL, while the other 17 proteins were found only in cyclic CL. Among the above 6 proteins, vimentin which is involved in the regulation of post-implantation development was included. Thus, the protein expression pattern in CL was disorientated from cyclic luteal phase to mid pregnancy, and alterations in specific CL protein expression may contribute to the maintenance of pregnancy in Korean native cows.